Barróg - Featherweight Lifter Build Diary

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There's only a week to go until Mechatrons 2018

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Jeez, so there is. Better get my finger out!

Just a few quick questions to ask concerning the machine and live events in general:

1. I'm looking at using a 1-2mm 50mm long piece of stainless steel as a relatively lightweight wedge along the front for the event, chamfered at the sides and below at 45 degrees. Hopefully this drawing can explain better my idea. Would a wedge like this survive a 3 day non-spinner event relatively intact, or at least be repairable to the point of usefulness between bouts? Could I go lower than 2mm stainless steel, or should I go higher? Bear in mind weight and time is an issue for me, I'd ideally like to have a more long term setup for the future, but what can you do, right?

https://i.imgur.com/XNJlkMh.jpg?1

2. I notice the tech check rules state that a machine needs to have some sort of cradle setup for holding. Until now I've been using large HDPE offcuts to keep Barróg's wheels off the ground. Would this fly at an event, and if not, would it be possible to simply build a frame out of wood to hold it off the ground? Would I need straps to hold it in place?

3. Would the lifter require a locking bar? I know most pneumatic and kinetic weapons require them, but would an actuator require one as well?

4. When I turn off the transmitter, everything in the machine comes to a halt. I know of the removable link rule, and the machine has it, but would the halting of everything in the machine via turning off the transmitter satisfy the failsafe rule?

One last extra pic of the new revised lifter spines:

https://i.imgur.com/hUvb1Rr.jpg?1

To try and answer your queries:

1. The Honey Badger ran a 1mm thick Aluminium door finger plate along the front of the HDPE wedge and that did OK when the plate was wholly on the wedge as it was supported. At the Maidstone 2017, I moved it forwards and put it on hinges much to the same effect as you plan and it buckled horribly. I could straighten it out with a hammer but really, I'd advise against it. Steel might be better but I don't think it'll stand up at 2mm.

2. I use a wooden cradle with no straps and that has always been OK. It needs only to keep the robot off the ground and be stable enough so that if the drive wheels do spin, it doesn't come apart. Mine is very wide to allow for this.

3. Ask the event organiser on that one. I recall Luna-Tic asking this for the FW championships in 2017 and RoboChallenge said they didn't but this is one of those times where the event organiser needs to determine this. However, if in doubt, assume it does.

4. Yes. One of the tech checks is to check for exactly that (i.e loss of signal = no movement).

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The Honey Badger ran a 1mm thick Aluminium door finger plate along the front of the HDPE wedge and that did OK when the plate was wholly on the wedge as it was supported. At the Maidstone 2017, I moved it forwards and put it on hinges much to the same effect as you plan and it buckled horribly. I could straighten it out with a hammer but really, I'd advise against it. Steel might be better but I don't think it'll stand up at 2mm.

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Interesting. I feel I should clarify though that with the steel piece, the top half of it is bolted on to the HDPE front as opposed to being hinged, sorry if the drawing didn't express that clearly. If you were able to use a 1mm piece of Aluminium scraping along the floor, then I assume that a 1mm piece of steel should hold up as well?

I'll also get onto the event organizers concerning whether a locking bar is necessary or not; I can probably have it go through the front claws where they meet the front of the lifter, though I don't know if something will break or not should I operate it (front claws could be ripped up, gears in linac could break, etc.) It seems from what I've been reading on other build threads that FW lifters seem to get away with having no locking bar, but the "clamper" part of the robot's design may pose more of a health and safety concern.

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Originally Posted by Shooty

3. Would the lifter require a locking bar? I know most pneumatic and kinetic weapons require them, but would an actuator require one as well?

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Ask th EO but i would design it so you can in anycase, plus you could use the holes you need to drill as weight saveing.

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If you were able to use a 1mm piece of Aluminium scraping along the floor, then I assume that a 1mm piece of steel should hold up as well?

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Hmm... The design of my hinged plate wasn't flat like you are proposing, I had added a bend into it prior to the event but even without it, I still seriously doubt it would have survived, even if it was Steel. I still think that this was because it wasn't supported by anything. Had the wedge followed the contours of the leading edge of the HDPE beneath, it might have stood up better.

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Solid advice. Cheers for all of the info!

I used a strip of mild steel for my robot in a similar way as you plan to here. It was 4mm and stood up perfectly well to non-spinners. Personally I wouldn't go less than 3mm. If you used 2mm you'd need several spares and could be spending lots of time straightening it out after matches. Is the front of your lifter touching the ground without this addition?

Not sure if you'd get away with multiple little bits for a cradle - if you are tight on time you don't really have to build much though. My carrying cradle is just a thick, old wooden chopping board with big cut outs for the wheel area, so it looks like an I shape. If you have any chunky HDPE sheets leftover that you could fit between the wheels that would work too - so long as it's wide/long enough and the robot can't tip off it.

To be on the safe side I would put some sort of locking bar on - due to the nature of your design it shouldn't be too difficult.

Also what weight are your wheels? I personally haven't tried this yet, but I think at Insomnia there was several robots which had 4 holes drilled into the wheels in a square/diamond formation to cut down weight. Maybe try as a last resort?

Barrog is looking great by the way - nice work! :)

How did Barróg do at Mechatrons 2018? Did it make it in the end?

It made it. Videos are uploaded on the Team Ironclads YouTube page. Am currently making a build report video, should be out before the end of the month (if laziness doesn't take over...).

Well, it doesn't look like I'll ever finish that build report video, so I'll just fill in what happened at the event here instead.

So the final few days leading up to the event were entirely focused on three goals: losing as much weight as possible without weakening many of the key structures, fitting the front claws, and finishing off the electronics. For losing weight, I opted to drill holes using a hole saw in the lifter spines, the rear curves on the machine, at the front of the base plate (though leaving enough space around the front motors so as a nasty shock wouldn't snap the plastic), on the back plate, as well as hollowing out the lifter supports/bulkheads.

https://i.imgur.com/fNgMoTq.jpg
a shot of the machine with the front claws mounted, as well as the holes in the spines and sides

After about a days worth of cutting and a years worth of swarf, the front claws were done. They were mounted simply to the base with two bolts each, and while I was worried about how much pressure they could take, they seemed to hold up well. They also gave me an idea of where I could mount the electronics within. A safety loop was added before the main circuit (link, 60A battery fuse, LED power light), 30A fuses were installed before each ESC, and a 20A fuse was added to the linear actuator. figuring out how to mount the battery was tricky given weight limitations, so for a small event like Mechatrons, I opted to cut out a slot in some corregated cardboard that would hold the battery snugly, and use velcro ties to keep everything in place. The end result wasn't the tidiest, but it weighed very little, and could survive a few tumbles.

https://i.imgur.com/P2pnTVF.jpg
a shot of the electronics prior to the event

With everything in place, I decided to test out the force outputted by the linear actuator by "grappling" some weighing scales. I decided to stop when I read 55kg on the scales! Unfortunately, another test against a small, thick cardboard box placed too much pressure on the center of the green piece, causing it to crack. Frustrated at this, I ended up needing to cut an extra piece using some offcuts to reinforce the vulnerable area, as well as a few extra nuts and bolts. Despite this however, I was actually slightly underweight from all of the holes, and after finally caving on drilling holes on the front piece of the robot, all that was needed was the metal sheet up front and something to stop it getting beached.

DAY 0

We drove down from Galway on the day before the event, and ended up being one of the earliest teams to arrive (team might not be the right word considering I was the only person at the event who had anything to do with it prior but whatever). I met Peter, Zulu, and many of the other crew members, and was given a place in the pits right where the guests wait to be allowed into the show. Much of the first part of the day was spent setting up and oogling the new King B (partly because it was one of the only other heavies there at the time, and partly because, well, it was the new King B).

https://i.imgur.com/dA2E8fM.jpg
Barróg from the front

https://i.imgur.com/gGPUMZX.jpg
Barróg from the back
https://i.imgur.com/YM0ayzf.jpg
Another shot of the innards

https://i.imgur.com/pz43Lij.jpg
An example of Barróg doing what it was built to do

A few things to note from the new pictures. The holes and the support piece along the front ended up looking a lot better than I thought they would; in fact, if I had known even a week beforehand how the holes would have looked, I would have drilled a whole lot more! I ended up ordering two sheets of metal that were fairly cheap for the front, and the 1.5mm stainless steel could get very low to the ground without catching on anything, and if that would be an issue, I made it a policy to keep the lifter slightly open while driving. I settled on threaded bars along the sides which would prevent Barróg from getting beached on its side, but would not help it if it were stuck 45 degrees upside down (ooo... foreshadowing...). Ultimately it came down yet again to time and weight, which by now have become dirty words to me.

I was a little anxious coming up to the safety check that not having a locking bar for the claws would disqualify me from fighting, though I had gotten reassurances from Peter Redmond that the slow nature of the clamper would allow it to avoid this rule. I had a threaded bar with me, and would have been able to drill holes in the front claws where they meet the green piece so as to prevent the machine from opening, but this would have been an untested option, and could have led to the front claws breaking, or the actuator just breaking through its mounting. After using the machine, I highly doubt both of those things could happen, but it was something in the back of my head at the time.

The safety inspector went through the operating procedures of the lifter and, fortunately enough, there was no problem. What DID end up becoming a problem for me however was the transmitter I was using, a modified Devo 7E, which decided, for the FIRST TIME, on that VERY DAY, with NO WARNING, that the power switch being set to the "off" position wouldn't turn the machine off. With this, I wasn't able to demonstrate that in the event of a loss of signal, the machine would turn off. If I couldn't do this, I would be disqualified from competing. In theory, I could have my batteries hanging out of the transmitter, and just disconnect the lead connecting the two whenever I wanted to show the events of a loss of signal, but fortunately for me, before having to resort to that, I was able to get help from Jamie of Team Coyote and Tony of Team Rusty, and was given a loan of a spare Spektrum DX6i for the event. The robot was rewired to work properly with the new transmitter, and I could pass safety. I was good to go for any fights tomorrow!

https://i.imgur.com/t7gXE45.jpg
The faulty transmitter, which stopped turning off for me

https://i.imgur.com/b68NrGx.jpg
The Spektrum DX6i I used for the remainder of the event, which worked like a charm

https://i.imgur.com/IVljU6v.jpg
A shot of the Arena the night before, looking uncharacteristically smooth. Rest of event report to follow soon.

DAY 1

Overall, there were 12 heavyweight machines and 6 featherweights at the event, mine included. For the other featherweight machines, there was Beauty 2, a legendary pneumatic flipper, Carcinus (Car-sin-us), an electronic crusher from Team Coyote, Cicatrix (sick-a-tricks), a 4WD pusher from Team Scot-Bots, Red Hot Tilly Pecker, an axe bot from Team Tilly (some of you may recognize the FW as the robot formerly known as Hatchet), and Node, the only other Irish FW, which was meant to be a Shockwave/style lifter, but was effectively still in construction at the event. It was a pretty nice variety of bots, basically everything except a spinner, so perfect for testing out a new machine.

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Each event that happened roughly hourly would feature two fights, usually between heavies. On the feather end, two 3-way rumbles were scheduled for each day, and my first one was scheduled for the end of the day against Beauty 2 and Cicatrix. I had a lot of time to kill, which I spent talking to roboteers, taking advantage of the food vouchers provided by the expo (roughly £9 per day), and explaining to those waiting for the show to start about the robots, their weapons, and explaining to them how to build an antweight. I even made a makeshift arena for my antweight to drive around in, giving the controller to various audience members.

https://i.imgur.com/bbLQW5b.jpg
A crude arena for driving my flipper AW, Sioc, around.

Eventually it came time for my first fight, and I was pretty terrified of Beauty, as while I could self-right on my back, there were certain positions that I could not come back from. I brought the machine down to the arena, armed up, and drove over to the end.

​FIGHT 1:

https://www.youtube.com/watch?v=bnJ4EoYGU2M

Some observations from the fight:

• ...I have no idea what that enterance music was, we were told we could make requests for what to play (mine was Dearg Doom), but that apparently wasn't the case. In retrospect, a lot of the other intros made a lot more sense with this in mind (Thor had "Do You Like My Sword" as it's music).
• Most of the first minute was getting used to steering Barróg; the machine was backheavy by design so as to be controllable with a robot on top of the front, but the downside to this was that it powerslides quite easily.
• Beauty 2's flipper had problems throughout the event, and as a result never fired once. I didn't realise this until after the first minute, and so played it very safe when driving around Beauty 2 until then.
• Cicatrix had traction problems throughout the event, leaving it stuck for large portions of fights. This is probably why when Cicatrix tried to push me at the 2:05 mark, I was able to push them right back.
• The 1.5mm steel strip performed quite well in the fight, mainly as I was able to keep it off the ground when driving normally, and lowering it when going for a charge. This meant I could get under Beauty 2 fairly consistently, while having enough ground clearance everywhere else so that getting beached was not an issue.
• Getting Barróg directly in front of other robots was an issue, as was getting a grip on them. I tried not to put more pressure on the front then what I thought was necessary for fear of self-damage, and as a result a lot of potential "grab" opportunities slipped me by. I did however manage to get one grab on Cicatrix though around the 3:50 mark!

POST-FIGHT:

Safe to say, I was feeling pretty chuffed after that first rumble. On trying to push Cicatrix back over to the arena entrance however I noticed that my pushing power had greatly diminished. I brought the machine back over to the pits and took a look at the damage.

https://i.imgur.com/2n9SJiw.jpg
The state the steel strip was in at the end of the first fight. Easily removed and hammered straight before the next fight.

https://i.imgur.com/iJQp9jr.gif
Some of the scuffs along the front of the robot. Mostly cosmetic.

https://i.imgur.com/xNx6VNn.gifhttps://i.imgur.com/DBRFWF7.mp4
The rear left wheel. It was not supposed to be spinning freely.

DAY 2:

My main focus for today was to figure out what was wrong with the rear wheel and to try to fix it. As you can see from the image below, there were several problems with the gearbox. The first were the visible cracks around where the ball bearings were (they were simply held in place by the tightened torque limiter as opposed to grub screws, I paid for this by losing a few bearings), clearly showing signs of stress. The second was that one of the metal pins that held the planetary gearbox on the inside together had slipped out, removing any contact the motor could make with the wheel. Fortunately, Team Node had written off on of their drill motors, and I was able to salvage the metal pins from it to restore functionality to the gearbox.

https://i.imgur.com/cQXdCly.gif
The damaged gearbox

With all four wheels working again I was able to enter by second fight, between Beauty 2 and Carcinus.

FIGHT 2:

https://www.youtube.com/watch?v=AhfqmB08Bzw

Some observations from the fight:

• This fight was originally going to have Red Hot Tilly Pecker fighting, but unfortunately they had burnt out a motor in the previous fight, and so Carcinus was brought in as a reserve.
• The introduction was the first time I really drove the machine with the lifter all the way up, and I discovered that it was impossible to control like this. That hit on Beauty 2 at that point was a total accident.
• Slower movements seemed to allow the machine far more control then last time. over-correcting was still an issue, but I was definitely getting more "good lifts" then last match
• At the 3:05 mark, it wasn't caught on camera, but at that moment I decided to spin wildly just for the attention of the crowd. The machine actually started shaking back and forth while spinning at this point! Pretty sure I lost a wheel here as well.
• At 3:20: another good lift! Probably the best one I got at the event.
• From 3:30 onwards I lose a front wheel as well, and at this point the machine's mobility is greatly reduced, a fact both Beauty and Carcinus capitalize on.

POST-FIGHT:

So after this fight, Barróg was limping pretty badly. As well as the dents to the front strip, I had lost both the front left wheel and the back right wheel. one of the wheels was fine, but the other was cracked, and the gearboxes were an unknown for me at this point. I decided to purchase two drills on the way home (one of the gearboxes was more damaged then the other, I thought the other could be salvaged) and elected to fix everything tomorrow.

(This post has reached the character limit, the rest will be posted shortly)

DAY 3:

This day was a total rush, and 80% of this was all centered around getting working wheels, including such things as dismantling half the robot to get to the rear wheels (a real design fault). It's at this point that I need to explain how the wheels were mounted. They were hard plastic, tapped onto the shaft of the gearbox, and held on tight with the reverse-threaded screw and a washer. I thought that these would be the point of failure before anything else; in reality they worked too well. I was unable to screw the wheels off, as I had nowhere to grip onto the gearbox that would stop it spinning. This meant that the front motor brackets were stuck in between both the wheel and the broken gearboxes, and if I couldn't get those off, then I wouldn't be able to mount the new motors.

https://lh5.googleusercontent.com/XQ...azL-w4OqTWh1Cg
A shot of a wheel held in place by a reverse-threaded screw and a washer. Notice the crack as well.

In the end, I ended up having to cut open both gearboxes, and use a vice grips on the inside of them to finally, slowly, remove the wheels. After dismantling both drills, the soldering of new connectors, and the dismantlement of the entire machine, followed by reattaching the wheels and rebuilding the machine again, I didn't even have enough time to hammer the steel front strip back in place, and so opted to use the replacement one instead. I also used zip ties across the metal pins so that they wouldn't fall out this time. I tested everything and was back to being fully operational in the nick of time.

https://lh4.googleusercontent.com/xZ...yKkv9g4TDKrpII
Node, in the best condition it had ever been.

The final fight would be a 6-bot rumble, including Node, whose machine was finally working (sort of). I brought Barróg to the arena, armed up, and was ready to fight.

https://lh6.googleusercontent.com/Te...NnEywHL6-PFkVc
A shot of the six, ready for battle.

FIGHT 3:

https://www.youtube.com/watch?v=PfkRH03HQXg

Some observations from the fight:

• The opening was a total disaster. Cicatrix and Carcinus each ended up stuck at certain points, Node didn't move at all, and machines were being misnamed left and right.
• Almost immediately, I noticed I had lost a rear wheel, and as a result I couldn't drive straight for the entire match. Grr!
• I started to shuffle towards Node in the hopes of parading them around the arena, but couldn't get a grip on them due to my missing wheel.
• Speaking of Node, they died immediately, and everyone ended up laying on them at some point in the fight, which leads to my favourite shot of the whole event at around the 3:40 mark: Node is flipped by a charge by Beauty, Tilly Pecker starts going mental on them, I try to drive in and save them but can't keep the machine straight, and then one more charge from Beauty straight up kills the LED's.
• At around 4:45 I try to go after Tilly Pecker, as we had both won our rumbles and were competing for the grand title (or whatever could be considered a grand title for whiteboard rumbles). This leads to 5:20, when I start getting whacked relentlessly, and I even try raising the lifter just to take a few less hits to important areas.
• At around 5:45, just as cease is called, Barróg gets flipped over for the first time, and in a position I cannot recover from as well. Fortunately, all the weight below meant that a light nudge was all that was needed to right myself again, so this is a good sign for future friendly matches!

POST-FIGHT:

The main thing I was interested in was to find out how I had lost a wheel early on. As it turned out, I had simply forgotten to re-insert the reverse-threaded screw which held the wheel in place, and as a result the wheel came loose. It still supported the machine from dragging on its corner, but the threads were completely shattered as a result. I also took far more damage this time as well thanks to Tilly Pecker, which left marks mostly in between the two front grabbers and at the back-right corner of the main face.

https://i.imgur.com/xXzXace.jpg
A shot of the front of Barróg after the fight.

Fortunately, outside of the cosmetic damage, everything still worked fine. The electronics hadn't failed at all during the event, and despite running on three wheels for the entire fight, the gearboxes and other wheels came out without a scratch, so I've finally gotten a reliable drive.

https://i.imgur.com/uKjeV3o.jpg
A shot of the underside of the lifter where Tilly Pecker kept hitting me. Look at that crack!

POST-EVENT THOUGHTS:

• Upon returning from the event, I discovered that low batteries were the reason my transmitter wouldn't turn off. I was confused by this, and still am to an extent (I've never heard of something refusing to turn off on low power, usually it's the other way around). I'm going to give the transmitter one more chance at Manchester on a new set of batteries (beats spending triple figures on a new transmitter!).
• I was pondering for a while how to get wheels off of the gearbox shafts, even thinking of cutting a slit down the center of them to allow for a flathead screwdriver to grip. It was only after the event that I realised I could just run the motors while holding the wheels, and they'd just screw off that way. Oops, knowing that could have saved me some money in broken gearboxes! I now have a setup for doing just that using a scrap piece of HDPE.
• I need to come up with a better way to prevent Barróg from getting beached, while still meeting the weight limit. Possible areas for losing weight include more holes on the front green piece, and more holes at the back, covered with a strip of polycarb to protect the internals (though polycarb has a higher density than HDPE, so I wouldn't be saving much unless I was using very thin polycarb).
• I'm planning to have an alternate configuration for Barróg, where the front wheels and the two front grabbers are replaced with just the front and a nice thick piece of Hardox along the edge. Mostly for spinners, I just need a low-weight way for mounting some free-wheeling wheels along the front.
• I'm also planning to drive some screws through the front grabbers for better purchase when grappling something, I noticed machines would slip out very easily.

https://i.imgur.com/Aq8fKw8.jpg
A shot of the dismantled Barróg, before cleaning the pieces of the dust accumulated.

Before ending this post I'd like to thank many of the people at the event who helped me along. I'd like to thank Peter Redmond, Dr. Zulu, and all the event organisers for organising everything and helping the show run along smoothly. I'd like to thank Simon Harrison and Natsuko Hori, who were both so lovely and friendly, Jamie and Tony for helping out with any of the technical problems I faced and providing certain tools, Shane for also being very helpful with knowledge and just beign friendly, and the Prophet family (Team Ironclads) for recording the entire event. I'm hoping to bring Barróg to Manchester later this year with whatever improvements I've made to it. I'm also trying to design my first beetle, which should hopefully make it to the Euro champs later in the year. It was a great event, and I'm hoping to return again next year!

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Update time! So with Manchester coming up in a few weeks, I've been looking at ways that I can improve Barróg to sort out its problems. The first two have to do with the front claws. I noticed that machines could easily slip out of my grip due to the slippery nature of HDPE, so I've elected to drive a screw through each claw point for better grip. The screws will only be poking out a small bit, less than a centimeter, but it should give me some much needed grip. I may even put some green ink on them before battles so that I can see where I've gripped other robots after (probably not though). the second change is that I've noticed that the claws can sometimes catch on the sides of the lifter, so I've elected to chamfer the sides of them to prevent this from happening in future.

The major change however has been the need for a self righting mechanism for when I'm on my side. the bolts did a fine job for the most part, keeping the machine on its wheels and under the weight limit, but they look ugly, and prevent the machine from self righting on its side. So, I've been working on a design that would incorporate self-righting wings into the bot, where they are activated by the lifter raising via a connecting cable.

https://i.imgur.com/YoOyUTU.jpg
Quick sketch of the idea

https://i.imgur.com/pT67yd1.jpg
Test-able prototype made from an old offcut


Unfortunately I cannot upload a video of the test myself, but suffice to say, there were problems with the prototype:

• The cable I used, which I quickly swiped from the charger of one of the six drill batteries I now own, snapped. I need a stronger cable, but this was obvious.
• The wings wouldn't go out far enough to self right. The hinge point needs to be lower and closer in to the wall.
• All of the bolts on one side ended up weighing 100g, twice what the 8mm bolt used to weigh.

My current plan is a revised version of these wings, using some green 12mm HDPE offcuts instead, twisted 90 degrees so that the width is the side taking the weight. Less bolts will be involved overall, and I'm looking at using torsion springs to keep the wings inside when not in use.

https://i.imgur.com/0tVr7Ib.jpg?1
An idea of what I want to do. Green piece in the drawing is not to scale

Barróg has been packed up and is ready for it's UK debut in Manchester. Unfortunately I could not get the self-righting wings working in time; I need a stronger cable as the light ropes I've been testing with just can't cut it, and supports are needed on the inside of the side walls so that it doesn't bend under the pressure. Changes have been made to the machine though, which should make the current iteration operate more smoothly.

https://i.imgur.com/JB7gJ17.jpg

The battery at Dublin was held together by cardboard, velcro, and hopes and dreams, so a proper setup is needed to deal with being tossed around. This new setup uses packing foam all around the battery, and some thin mounts at the front and back to prevent it moving forwards and backwards. The velcro strap seemed to hold together well last time, so I've elected to use two this time around.

https://i.imgur.com/P2m9dLg.jpg

https://i.imgur.com/hSW5SOx.jpg

The front claws on Barróg have been modified so that the sides are all chamfered so as to prevent the lifter catching them on elevation and descention. Screws have also been added up front to get a better bite on machines when holding them in place. The large washers have also been moved on to the bolts connecting the front piece and the lifter spines, so as to stop the plastic from splitting further.

https://i.imgur.com/jjGyn1H.jpg

Here's how the machine looks like at the moment. I've kept the bolts for this iteration as they're better then nothing. My problem at the moment now though is that the lifter ESC seems to have stopped working as of last night. Power is getting to it, but I'm not getting any output from it. I've troubleshooted it to the best of my ability, but it seems that I'm going to have to buy another Mtronik's Viper ESC, though this time rated at a higher amperage so as to minimize any risks, and have it shipped to Manchester and install it there. I don't know what exactly caused it to stop working, but I suppose those are the risks when using uncommon ESC's.

Alright very late update but technically within the month of the event so not too terrible. Here's how Manchester went for Barróg.

DAY 1:

https://i.imgur.com/M7JDreb.jpg
A shot of Barróg loaded up into the car

We ended up taking the Dublin/Holyhead ferry early Friday morning, which gave us a little free time in Manchester proper that day. We arrived at the event and were stationed next to two other FW teams, Team Kaizen (The Honey Badger) and Quantax Dynamics (Destroy It Yourself). Barróg passed another tech check (always a nervous time due to the grey nature of the weaponry), and most of the time leading up until the first fight was spent making sure everything was secured in the machine, as well as looking around at some of the other bots. The build up to the fight was particularly nerve-wracking due to it being the first fight I (and I assume many other teams) would be fighting a spinner. The first fight could have been a whole lot scarier though, as of the three "verts of the apocalypse" (Shrapnel, Blunt Force Trauma, and Get Shrekt), only Shrekt was rolling this fight.

FIGHT 1:

https://youtu.be/Ka3e7GECYHw?t=26m9s

Some observations from this fight:

• The new FW house robot that has replaced Oll-E (to what seems like to no ones remorse) was unexpectedly awesome looking, and I only found out it had a flamethrower after entering the box. That was fun, both in the terrifying way, and the fun way.
• After 20 seconds of driving around, I suffer what I can only describe as a series of unfortunate events. Barróg gets flipped by the flipper into the only position it can't self-right from, proceeds to become the first machine to be effected by the CO2 jets by way of getting blasted around, and finally get toasted by the house robot before finally getting back onto my wheels.
• At I proceed to get my first good lift on another machine, however it seems that I didn't leave the throttle stick in the neutral position completely, and once they slip out, the front proceeds to spring up, something it is not supposed to do. it takes another few attempts for me to figure out that the back of the lifter is rising instead of the front when I get underneath opponents, signalling that something has gone very wrong with my defining feature.
• After being reduced to a wedgebot, I go for one final push on an opponent, before becoming completely dead, the first time to happen to me, before being pitted in the dying seconds of the rumble.

POST-FIGHT:

So obviously, there were some points that needed addressing with the machine. The front wedge was mangled a bit, some bolts on the wheels needed tightening, and it turns out that the reason I was dead in the water was because of the battery connection came loose, so that was easily remedied. I would be remiss to mention the most important casualty though, which was the lifter.

https://i.imgur.com/abh6y9n.jpg
Ow

As it turns out, the lifter kept raising long after grabbing its target, and while I don't know exactly how much of a load it took, I so know that it was enough to completely snap the HDPE front into two pieces, where the part of the lid connected to the linac came completely apart. In hindsight, the area was not properly reinforced for how far it was back, and will hopefully be fixed for future incarnations. So while I worked on getting the wheels and wedges back in order, my dad and cousin worked hard on assembling a support bulkhead that would restore functionality to the lifter, and reinforce it greatly. With this new support Barróg was reborn now, presumably, with the power of Christ on its side.

https://i.imgur.com/FYOQqwc.jpg
The new setup, certainly more durable

Barróg was in full working order for fight two, which featured the three verts, as well as Blinky, another vert who made a surprise appearance. You know, the "that wasn't a fart" kind of surprise.

​FIGHT 2:

https://youtu.be/Ka3e7GECYHw?t=54m33s

Some observations from this fight:

• This fight was actually pretty passé for me compared to the others. The lifter wasn't used much, whether that was down to caution on my part or technical failure I cannot remember.
• much of the fight was just me trying to avoid the spinners, whom seemed to not be causing as much destruction as usual, which was a pleasant surprise.
• I'm starting to realise that even with a broken lifter, the design of my wedge coupled with the claws stopping machines from driving over me, as well as a 4WD make Barróg a pretty nice pushbot, which comes in handy when necessary.
• Personal highlight for this fight was unknowingly ending up behind a still quite dangerous Blunt Force Trauma, where I proceeded to ram it into the wall, all while screaming loudly.

​POST-FIGHT:

After the last fight, I was pretty chuffed to survive the full three minutes in a spinner rumble, and aside from the wedge, the machine was still fully operational, the lifter hadn't broken, and I even got to fight in an off event "test", though after that, I noticed that two of my wheels were shagged, and so both spares I had needed to be used up.

https://i.imgur.com/mQ5kyWw.jpg
Barróg sustaining only cosmetic damage, an improvement over last time

Day two post to follow shortly as I've reached a character limit.

​DAY 2:

https://i.imgur.com/INtIwFd.jpg
in awe at the size of this bot. absolute unit

Getting the two wheels replaced as well as sorting out some last minute technical issues ended up taking up longer than I thought, from getting the gearbox shafts clean of plastic to taking the thing apart to put the wheels on in the first place. Fortunately, and after a scare with time management, Barróg was ready for fight three. This time, Drumroll also made an appearance at the event, bringing the total of spinners up to five, making for a rumble that I'm fairly certain is imprinted in the minds of many on the forum already.

FIGHT 3:

https://youtu.be/Ka3e7GECYHw?t=1h25m50s

Some observations from this fight:

• Barróg was finally reaching a point where I can call it decently controlled. It still overshoots a bit, but for the most part, I was going after people who I wanted to go after, and seemed to win most pushing contests it got involved in.
• Personal highlight of the event was getting under Blinky's wedge, having one of my claws taken off by the disc, before driving full speed across the arena and into a wall. Unfortunately it seems the linac connector was undone with this hit, and so I couldn't get that all important good lift afterwards.
• Around the midway point of the fight I start focusing on Get Shrekt, and make it my mission to pit them, coming close several times but falling just shy each time. Got a nice hit in on the microwave in the confusion though (let it be known that a microwave nearly made it to the end of the fight even after getting smashed several times by everyone).
• Shortly after, I manage to get under Drumroll, proceed to ram him into the wall, and lose the battery connector again, falling dead in the water, though at least spared further punishment (despite several verts coming a little too close for comfort).

POST-FIGHT:

Needless to say, this was by far the most damage Barróg had taken yet. The wheels mercifully were still OK, just needed to be tightened a bit. The sides had gotten slightly chewed up and the wedge up front was mangled, both no doubt due to Drumroll. Blinky had taken out the right claw, and the left had great chunks taken out of it. Inside both the linac ESC to linac wire, and the battery to safety circuit wires had become disconnected. The damage was repairable though, and I wasn't deterred in the slightest, though admittedly most of that came from working next to The Honey Badger, which was, well, y'know.

https://i.imgur.com/wZORGEJ.jpg
A shot with a good overview of all the damage Barróg took, though the left side had far more bites taken out of it, not shown in this photo

https://i.imgur.com/iTMSZzX.jpg
A better shot of how the left claw looked after taking a few Blinky shots. Pleasantly surprised it held

At this point two problems presented themselves to me. the first was remounting the right claw, fixed together with a simple piece of plastic and a few screws. What was weird at this time though was my transmitter seemed to stop working, and the machine wouldn't move when turned on. Fortunately, Greg from Quantax Dynamics gave me a spare transmitter he had to test out as a thanks for me giving him two reverse threaded screws on day one for his gearboxes, and after a few tweaks, the machine was moving again. The front wedge was replaced with my spare, and Barróg was ready for its final fight of the event.

https://i.imgur.com/FptD1Fp.jpg
Barróg in the loading area before the final fight, next to fellow lifter/clamper Aegis

FIGHT 4:

https://youtu.be/Ka3e7GECYHw?t=1h53m29s

Some observations from this fight:

• While driving into the arena, I noticed the new transmitter wasn't identical to my old one. In fact, the mixing was reversed on it, so while forward was still forward and vice versa for reverse, holding left made the machine turn right, and vice-versa. It was still fully driveable, but definitely tougher to do so.
• As the fight starts, I notice that Barróg also starts spinning at random intervals, which was a sign that something was definitely wrong.
• After a minute of doing sod all, I end up in the center of the arena, where something explodes within Barróg, a puff of smoke comes out, and it is dead, full stop. Luckily, I get shoved into the corner before too much damage is caused to the machine.

POST-FIGHT:

A disappointing final fight certainly, but at least no external damage was caused this time. After a later diagnosis, it seems that something went wrong with the linac ESC that caused it to draw ludicrous amounts of energy, possibly due to me not cutting the red wire on all but one BEC wire, where the left drive ESC then took in excessive energy through the BEC wires, and toasted the wire along with the fuse connecting it. I've reached this conclusion as when I inputted in the link again later with the left ESC disconnected, the linac ESC became hot and the battery fuse blew.

https://i.imgur.com/qIIzrYL.jpg
A shot of the toasted ESC. unknown if it would still work should I replace the BEC wire (I hope so)

POST-EVENT THOUGHTS:

• Fairly happy with how Barróg performed! Barring the final fight, I managed to survive one to the end, and put on a good show with the other two.
• Spinners were scary, but I found myself getting more aggressive towards them as the fights went on, and feel like I would be far more ready to face one in the near future, even 1-on-1. The body of the machine is certainly a little more worn, but functionally as good as the day it was built, am very impressed with how well 10mm HDPE has held up.
• The wedge needed to be fixed after every fight, and one of them had to be written off entirely, but they were bloody effective, and most of the damage to them seemed to be self-inflicted from bashing feathers against the walls. I reckon a more obtuse angle on the front should solve this problem somewhat, reducing effective wedge-y area but keeping it in peak performance for longer. Key point for me was getting underneath Blinky's front, a result I hope to replicate against future verts.
• The claws did well, proving useful even when the lifter wasn't working by catching other machines upon a successful charge. Nothing broke internally when one was snapped off, and I am now considering reducing them from 20mm to 15mm for weight reasons. Should still be tough enough for grabbing, will net me some nice weight, and will redesign them to alter the breaking off-point, possibly higher up, so that I can bring spares and simply re-attach broken off pieces more efficiently.
• The green front is a write off, but is at least handy for salvaging 12mm plastic off of now. The entire spine-support system needs to be redone to prevent breaks from happening again. The linac will probably go forward, reducing the speed and reach of the lifter but allows me more freedom with the supports and even increases that ever desireable crushability factor. the new support will probably be made using welds and 2mm steel angles.
• BEC's will be altered so that only one powers the receiver, possibly one of the drive ESC's. I'm going to give the linac ESC makers one more chance, and place the fuse before the ESC instead of after from now on. Botbitz ESC's are high on my shopping list now.
• While in Dublin gearboxes were the ones giving me trouble, it seems like the wheels gave me more to keep an eye on in Manchester. They hold for most of the fight, but start to come loose in the later half. I've gotten a few hex nuts now along with a wheel they slide into, but still need a way to secure the nut to the wheel. 50/50 on whether to stick with tapped plastic wheels or to transfer to nut-mounted wheels.
• All other improvements are still on the cards, notably the horizontal spinner configuration and the self-righters. I'll try to emulate Pressure Point's system, as it seems to be working well for Alan (EDIT: put down Dave first, leaving evidence of this as removing it is the cowards way out), I simply need to figure out how to secure the steel cabling to the top of the robot.

It was great to be at a UK event for the first time, and I had a blast. Next on the line is the FW champs in August, which should give me plenty of time to get the improvements up to scratch. I'm also going to be posting plans for a beetle in the near future, as soon as I get my copy of Solidworks usable again. Special thanks to Greg from Quantax Dynamics and Michael from Team Kaizen for sharing the pit with us. I hope Barróg can be the bot to represent Ireland for the first time in Birmingham later on this year!

https://i.imgur.com/v6k6eJ5.jpg
Barróg ready for the journey back home across the Irish sea

Glad you had a good time at Manchester, hope to see you at the championships. ;)

Cracking write up of the event and good to see Barrog performing well. Drop me a PM if you want any more details of the self righting system on Pressure Point.

Also, who is Dave? :p

Quote:

---

Originally Posted by Al_

Also, who is Dave? :p

---

Hi Dave how are you XD

Aw shoot! No idea how I messed up on that Al, sorry bout that! I'd be happy to PM you about the wings once I have a better idea of what the remodeled lifter will look like, cheers!

Work on Barróg has actually been pretty slow since Manchester on account of being busy with a few other things, but now that I've been accepted into Insomnia/KOB UK a fire has really been lit under me. While many improvements are in motion now there has only really been three major jobs done with Barróg:

1. The ESC with the burnt wires has been salvaged. Fortunately the signal wire survived the unscripted sizzling of the other wires, and with the other ESC acting as the BEC, it still controls the drive like new. The Linac ESC is still a bust, but spare Botbitz ESC's have been purchased, and should do the job just fine.
2. A great slab of 15mm HDPE has arrived, and one of the new claws has already been made. All angles have been rounded off to reduce stress on critical breaking areas, and having the claws like this gives me far more weight to play around with. They may not survive as well as the 20mm would, but I have enough HDPE now to make 5 claws total, so I can bring along 3 spares in the event of breaking.
3. A new lifter bracket has been made. the 20mm HDPE block system has been replaced with 3mm welded steel, and together with the actuator being moved forward for a less aggressive angle and the welded tabs at the side to share the load with the lifter spines, my lifter should be far more durable, and less at risk of breaking itself.

https://i.imgur.com/XrnUtTe.jpg
The new 15mm claw next to the original 20mm claw.


https://i.imgur.com/CLSfnUa.jpg
New lifter bracket. Actually weighs almost as much as the old setup.

My main issue now is that I am writing this build log in a hotel on a remote island off the west coast of Ireland, and that combined with work in Dublin, leaves me with 4 full days of actual physical work that can be done on Barróg before going to the UK. Fortunately, almost every job that needs to be done is already set into motion one way or another:

• Spare claws: HDPE ordered, 1 of 5 already cut.
• New 12mm HDPE front: bought, already started cutting. Needs to be positioned, and slots to be cut out for the front claws. Spare ordered.
• Horizontal spinner killer: Drawing made and sent to Kcut (Thanks Jarvis/MicroGravity100), waiting for quote. HDPE front ordered.
• Spare wheels: already received, need to be tapped.
• Self-righting wings: last on the list of things to do, but advice received from Alan/Al_. Idea in head of what they will look like.
• In Case Of Explosion secret weapon: Heat gun ordered.

https://i.imgur.com/KzUqcc9.png
New spinner killer wedge design. Weighs about 1.5kg, as much as losing the front claws plus the front two wheels.

If all of this can be done, then I should have a plan for dealing with all but one of the bots that should be at KOB UK (curse you Straddle 2!). Here's hoping I can get all of my upgrades working in time.

Well, this update post may be *slightly* late, but here is an event report for Barróg from KOB UK/Insomnia 63.

As stated before, I didn't actually have a lot of time to make all necessary improvements, but fortunately, with the exception of the self-righting wings, everything else was finished. New front claws were cut, chopping boards were prepared giving me two front pieces for the normal configuration and one reserved for the horizontal configuration. Speaking of, the great slab of hardox required for the setup arrived, and fit the machine like a glove. Screws were also added to the front claws to hopefully improve grip. Bracers were also added to the front piece so that the top wouldn't sway side to side at the tip.

https://i.imgur.com/CQu5hIZ.jpg
My living room after a days worth of cutting. Try not to work next to carpet if you ever start cutting the stuff.

https://i.imgur.com/PJvr6y3.jpg
One of the new front tops fitted on, with the old one visible in the background.


https://i.imgur.com/fqxhB9d.jpg
Just a photo taken for fun to show the sheer reach Barróg has. Fully extended it reaches 80cm!

We were at the point where work was still being done on the machine a day before the competition, only this time in Dublin instead of Galway. A lot of these were just dealing with spares and finalizing the electronics setup. The machine actually stopped responding to any radio signals at this point, and I was starting to get nervous (though I would learn later at the competition that I simply had the ESC's plugged into the receiver upside down, oops!). The final thing to note was my new "In Case Of Explosion" secret weapon, three HDPE wedgelets bent and digging into the ground. This way, I could have ground-scraping, weighted, easily replaceable wedgelets for dealing with any flippers and vertical spinners (Explosion being absent from Insomnia this year sorta made the name meaningless, but what can you do).

https://i.imgur.com/SE8P2HX.jpg
A look at what the house in Dublin looked like, the swarf is mostly from far, far too many weight-saving holes.

https://i.imgur.com/FuYi9Fd.jpg
The new HDPE wedgelets looking fine, angled 45 degrees at the front.

KING OF BOTS UK 2018:

Me and my dad got the ferry from Dublin to Holyhead like with Manchester, and arrived to the competition ready for the opening ceremony, as well as any safety checks and weigh ins. Barróg was gotten functional again thanks to the help of some other roboteers, the new wedges were attached, and the machine was now ready for its first fight.

https://i.imgur.com/1YYmjQ5.jpg
Barróg in its standard configuration, weighing approx. 13.45kg.

https://i.imgur.com/4jR9YGd.jpg
Barróg in its horizontal spinner configuration, weighing approx. 13.1kg.

FIGHT 1: QUALIFYING MATCH NO. 1

My first fight was up against Bane, a linac front-hinged lifter, and Utopia, a flipper. The version of Utopia meant to fight unfortunately wasn't finished in time, and so last years version was competing instead which, while very successful at Insomnia 61, was very battered at this point, and as a result didn't have a working flipper. Bane was somewhat of an unknown power going in to the fight as well, and given that I could get stuck upside down certainly posed a threat.

https://i.imgur.com/zXGLq1n.jpg
Barróg ready for its Insomnia debut!

(Special thanks to Jonathan Leighton-Hoggett, who filmed and uploaded his own version of all the fights this year along with the RobochallengeTV streams)

https://www.youtube.com/watch?v=J4hInBgTQWc

Some observations from this fight:

• Love the "That's gonna get trashed. Not this fight, but it's gonna get thrashed." comment at the beginning there.
• The wedgelets were actually really good at the start of this fight, even managing to get under Utopia's metal, ground-scraping wedge. After a few whacks though they seemed to lose their effectiveness, so a flaw has definitely emerged with the idea.
• Somehow I ended up beaching and immobilizing Bane by sheer accident. The slopes on the arena wall definitely proved to be far more lethal than I think anyone thought at first.
• Gareth's a really good driver, and he definitely had the edge on me in our first few meetups. After a while though I started to figure out ways to get around his driving style, and so started to predict Utopia's movements and could keep my front end in contact with him more often.
• Near the end of the fight I finally get a bite on Utopia, and try to bring him into the pit. Unfortunately I overcorrect somewhat, and we both end up in the pit, unable to move.

POST-FIGHT:

Damage wise Barróg was fine, with only a bent wedgelet and some batteries to be recharged. The real question on everyones mind was who had won the fight, as the winner would receive 4 points, and the second place 2 points. While Gareth to his credit asked for a rematch, ultimately a new rule added this year would decide the match. Due to flippers continually flipping themselves out of the pit in previous years, the rules were changed so that contact with the bottom of the pit would result in instant elimination, and as Barróg made contact with the bottom first, Utopia was given the win. I respect the decisions of the judges, though I am still a little disappointed that I lost such a good opportunity for a win, especially since I thought that this would be my easiest group. Still though, plenty of opportunities awaited me, and so I prepared myself for the fights the following day.

After the first days driving mishaps, I wanted to make sure that I wouldn't kamikaze myself again, so I wanted to practice driving around with a weight on the front. Fortunately, Team ACE from the last match were happy to lend Bane to be used as driving practice, which I was grateful for!

https://www.youtube.com/watch?v=X3ngdl4rNJ0

FIGHT 2: QUALIFYING MATCH NO. 2

My second fight had me facing off against Raving Luna-Tic, a linac lifter, and Blunt Force Trauma Remix, a vertical spinner. RLT was pretty nippy with its brushless drive, and the lifter could always be a problem if it got me right. BFT Remix was the scary one here though, doing a ton of damage over last year, as well as nearly beating Explosion and smashing fellow grabby bot Mantis 2 at last years Insomnia. More than any other fight, this one could be determined by whichever bot betrayed the other, as while we could both probably take BFT Remix together, one good hit could send either one of us across the arena.

https://www.youtube.com/watch?v=L--sd6puaR4

Some observations from this fight:

• I was ready to play this fight a bit more carefully, and so was very mindful about when I would strike. Fortunately my driving seemed to do the job, and BFT was more focused on RLT for the first half of the fight at least.
• Interesting to see the difference in materials at work in this fight. RLT's wedge was bent considerably after a frontal hit from the vert, but a similar hit on Barróg only took out a small chunk of the front plastic as well as a wedgelet.
• BFT Remix had installed arms to the side of the bot so that machines could be guided into the spinner. As it turns out, these were more of a liability than an asset, as they gave me the prefect path to get under the bot somewhat consistently.
• Near the end of the fight, I make my worst driving error yet. I try to pit RLT, but unfortunately I miss and end up driving into the pit myself, thereby securing third place for me. Dammit!

POST-FIGHT:

So the end of the fight certainly was dramatic. Roughly three seconds after I had gone in the pit, BFT Remix finally landed a massive hit on RLT and sent it rolling right of the arena. What's more, I would later find out that after that hit, BFT Remix was dead, and wasn't able to move at all. If I could have just stayed out of the pit for 5 more seconds, I would have gotten the full 4 points, but instead I was two fights in with only 3 points total. Really disappointing, but I still had one more fight left, and a small chance remained of me getting out of the qualifiers, my main goal for this year.

https://i.imgur.com/GyUhhM4.jpg
The front plate after Blunt Force Trauma Remix. pretty chewed up, but still fully functional.

FIGHT 3: QUALIFYING MATCH NO. 3

My final qualifier was the reason why I was so concerned about having the horizontal setup on Barróg. My oppenents were Vega, a shell spinner, and Apex FW, an overhead bar spinner, with both bots having the heaviest and second heaviest weapons in the competition respectively. Fortunately for me but unfortunately for them, both bots were having problems throughout the event. Pit buddies Vega had yet to get their weapon spinning, a problem made worse by their shell getting bent after a nasty hit from vertical spinner DB12, and Apex FW was rife with electrical issues, to the point of having to drop out of their second fight. In the end, despite being terrified of both bots going into the tournament, Apex FW had to pull out, and there was still a big question mark over whether Vega would spin or not. Nonetheless, I swapped out the front plates, and within the hour Barróg was back in the arena for its final match.

https://www.youtube.com/watch?v=OC_-GBekeps

Some observations from this fight:

• I had never actually driven the bot in this configuration, but from what little driving I did it seemed to do what I needed it to do. No complaints there.
• Upon the first lift I realised that my wheels wouldn't make contact with the floor if the bots center of gravity leaned forward, so I couldn't capitalize on the lift completely.
• Once I picked Vega up, I realised that I finally was doing what the original pitch of Barróg was before the front claws were added. I intended to go over to the pit, but I misjudged the balance on my bot and ended up on my back instead. Looking back at the footage, I really should have tried to "letterbox" Vega out of the arena instead, that would have been far more memorable!
• It was at this point that I realised a key flaw with the horizontal configuration. Normally, the machine would be able to rock back to normal, but due to the weight distribution with the horizontal setup, that was no longer possible. A bit embarassing to self-inflict a double KO, but what can you do!

POST-FIGHT:

I knew I had won the fight, but my main concern after the fight was how many points I would get for the win. Normally, a win by judges decision after three minutes awards 3 points, whereas a knockout first place grants 4. I would stand a chance to make it to the top 20 with 7 points, but not 6. Fortunately, the win was treated as a knockout, and I was awarded the full 4 points! All that was left to do now was to wait and see if 7 points would be the threshold, or if 8 points would.

Come the next day and the remaining qualifiers are played out. After some debate over certain matches, it was determined that nineteen machines had scored 8 points or higher, and eight machines had scored 7 points total. Thus, it was determined that the remaining eight machines would fight for the final spot in the top 20, giving me one more chance to get back into the tournament (later it would turn out that a few top 20 machines would have to drop out due to damage, so several machines from the eight way rumble would get back into the competition)!

FIGHT 4: TOP 20 PLAY-OFF

My opponents in the melee were Calabash Bros, a Chinese vert, Blunt Force Trauma Remix, the vert from earlier, Naughty Snake, another Chinese vert, Neon, an undercutter, Cobalt, a hydraulic crusher, Utopia, the flipper from earlier, and Orpheus, a clamper turned zombie less than an hour before the fight from an encounter with vertical spinner Shrapnel. Given the variety of opponents all I could hope for was to run the standard configuration this fight using my spare front piece, pray that Neon doesn't come towards me, slap another sacrificial piece of plastic on the front, and hope for the best.

https://www.youtube.com/watch?v=M5D1FmOn5JQ

https://www.youtube.com/watch?v=M3fIx_VSeZs

For this fight, I've decided to show two different camera angles, as it's hard to see all that happened from just one.

Some observations from this fight:

• From the start, my strategy was to hug the corner of the arena where the pit was and just pray I could outlast the carnage. Despite Neon coming a little close for comfort, this strategy seemed to work fairly well for 30 seconds, until Calabash Bros comes in and beaches me.
• At this point, I know I'm done if left alone, so I'm just screaming for someone, anyone, to hit me. Fortunately, Orpheus seems to hear me, and decides to charge me, get stuck under me, and bring me to the pit area.
• It is at this point that a miracle occurs, one where you could run this situation a thousand times over and not get the same result. I'm pushed into the pit at an awkward angle, but thanks to Naughty Snake being in there first, I don't touch the bottom (not getting caught by that again). At this point, I'm positioned just right so that when I close the lifter I rock down, and my wheels come in contact with the floor just enough so that I'm able to drive out. I was never unlucky in the previous fights, I was just saving all of my luck for that one moment apparently.
• At this point, all of the spinners are not working, and Orpheus and Calabash are stuck together, giving me plenty of time to just go to town on other bots and wedge like I've never wedged before. I got to have another go at Utopia which goes well, and its at this point that I realise just how effective the drive on Barróg can be. Take my advice, four 12V argos motors on 5S can get stuff done.
• Slightly concerningly, I seem to start to have radio issues in the latter half of the fight, where the bot seems to stop moving completely. It wears off, and would only return once in a later fight, but man, talk about terrifying!

POST-FIGHT:

Certainly a good showing from Barróg there, and a shoutout to Connor McBride and Orpheus for that performance (Orpheus would go on to place in the top 12, never underestimate solid internals, good driving, and duct tape). All four bots mobile at the end and BFT Remix would end up back in the competition due to dropouts, but Barróg ended up winning the play-off overall mainly due to how strong it looked at the end, and I was pretty chuffed at that. I had fulfilled my main goal, and now all I had left to do was to see how far I could go!

FIGHT 5: TOP 20

My opponent for this round was DB12, a compact vertical spinner that had landed some pretty nasty hits earlier in the competition. This would be my first proper 1v1 against a spinner, and I was excited to see how it would go.

https://www.youtube.com/watch?v=zsI9SCAen_0

Some observations from this fight:

• The plastic wedges were certainly effective at the start, but as time wore on they could only really get underneath DB12's rear. Still though, I do prefer them over the previous metal wedge, as with these pieces you would need multiple well placed hits to render them all ineffective.
• The other thing I start to notice is that while I'm taking a lot of hits to the front and side, I'm not actually flying with them or losing too many parts. I have some theories about this, but I'll save them for later in the post.
• It's at this point that I realize I'm suffering from a problem concerning my driving; I'm over-steering a lot, and this causes me to lose a lot of good oppurtunities throughout the fight.
• Several times throughout the fight I ended up getting stuck on top of DB12. An unusual situation, but at least I'm not taking any more hits than necessary, and am able to run down the clock all the more.
• After roughly a minute DB12 seems to lose drive. It's still able to use its weapon, but from here on out I'm able to remain the aggressor.
• My favourite moment of the fight comes two minutes in, when I'm able to shove DB12 against the wall and put a pretty sizeable dent in the bars. I apologized for it though at the time, so it should be all right.
• Eventually I seem to get DB12's one working side of drive beached, and with seconds left in the fight I seem to be awarded the knockout. It probably should've gone to the judges, but with the way the fight was going it doesn't seem like it would have made any large difference.

POST-FIGHT:

Safe to say this was an upset win for Barróg, and I was pretty happy to have gotten my first major 1v1 win! I was guaranteed a top 12 finish, and even though I would only have a short turnaround, the damage taken that fight wasn't that severe. All that was needed was to straighten the remaining wedgelets I had into something useable, replace the side bars to prevent beaching, and recharge the batteries.

https://i.imgur.com/lDzy8BK.jpg
A shot of Barróg after the fight. Notice how the front only seemed to get nibbled instead of ripped off, or the machine being sent flying.


FIGHT 6: TOP 12

So with the way the bracket works, I was due to fight the winner of the second top 20 losers melee, and of the five bots, DB12 would come out on top, and so we were due our rematch. Despite the previous win DB12 was still seen as the favourite, and I knew that I couldn't rely on the drive failing on them again.

https://www.youtube.com/watch?v=-dAHEO6QD3k

Some observations from this fight:

• I was wary of DB12's weapon this time round, so I decided to go for the pit ASAP. I knew I had the better drive when push came to shove, and I wanted to use that wherever possible.
• DB12 was definitely keeping closer to me this time round, and this made it a hell of a lot harder to get any openings. The wedgelets in particular were looking quite a bit flimsier this time round as well.
• At roughly 40 seconds in I get my first great shove in on DB12, and have him right where I want him, but unfortunately some oversteering on my part loses him on me. Definitely an issue to address.
• Ar around 1:10 DB12 gets his biggest hit on me yet, ripping off a considerable piece of the front wedge. I believe that this was due to him getting some speed with his attack, a fact I think Ed definitely noticed. Also at this point I seem to lose all signal for two seconds; not what you want happening to you after taking your largest hit yet.
• It is at this point that another miracle happens. Through sheer magic, I get into a position where I can push DB12 from the rear, and I'm able to capitalize on this just enough to get him near the pit and somehow remain out of it myself. Still amazed how I did this, but hey, sometimes you gotta know how to play with the hand you're dealt!

POST-FIGHT:

So after another great upset win I was ecstatic. This was my first proper FW competition, and I had managed to reach top 8 in one of the strongest featherweight scenes in the world! This fight was not without its cost though. The front wedge had to be written off and replaced with the original one from the BFT Remix fight, and many more improvements would be done on the final day before my top 8 match. Before that though, I'd like to discuss a part of my bots design.

https://i.imgur.com/HE6YvNq.jpg
Barróg after the fight. That front has seen better days.

https://i.imgur.com/sK2rMQx.jpg
A shot of the side walls at this point. These have been the same walls from day one, so this is all accumulated damage.

So at this point in the competition Barróg has taken a lot of hits, front, back, and sides. Yet despite all of the vertical mayhem, the machine has remained surprisingly functional and in one piece, where other machines have been disemboweled or ejected out of the arena by such beasts. I have a few theories as to how the machine has survived up until this point:

1. Barrel nut construction. These things have been incredibly sturdy, and while threaded inserts have came out of a few bots throughout the competition, I have not lost a single bolt, nut, or connection with these. Highly recommended.
2. Front wedge is brittle plastic. The HDPE chopping boards I've been using for the front of the bot seem not to be as flexible as the stuff from Direct Plastics, but that seems to have had the knock-on effect of simply chipping away instead of carrying the entire bot with it when in contact with a spinner. The only way it seems to take off more is to get some speed in before your charge, but this just means that I can never let a vertical get too far away from me, which is a touch better of a situation than the usual technique of "never let them touch you or you're dead".
3. Tall sides. This seems to be the key reason why I could just keep getting hit on the sides and just shrug it off. Most verticals are designed to be optimized against wedges, and use their oponents wedges against them to get the largest bites possible. With the tall boxy design however, I was always connecting with the vert at the point furthest away from the bot, and so I would only ever get a small gouge taken out of the side, and would be pushed lightly away, out of harms way and in a position to strike again.

Again, all of these are just theories, but if any of it holds any ground, then the design that was built out of necessity for my weapon seems to have been my greatest asset rather than my greatest liability, as while it isn't perfect, it certainly seems to give vertical spinners more trouble then they're used to, and given that they are a huge part of the robot combat meta right now, that makes me excited.

https://i.imgur.com/3RZo7ji.jpg
My highly technical drawing explaining my theory that I definitely didn't do in 5 minutes. Avert your eyes all those without engineering degrees.

So going into the final day, I had a feeling that Barróg could be better, and so much of the Monday morning was spent prepping the machine. One of my wheels was cracked so we tried to replace it, but it was stuck on so tight we had to destroy it to take it off, so it probably would have survived either way! 6 new plastic wedgelets were cut and bent (special thanks to Dominic Cartlidge for helping with that), and the top was swapped back with the original one. Finally, I needed a solution to the oversteering, so I adjusted the trims on my Devo 7E so that turning would only run the motors at half power. I felt safe to say that despite being in its 7th fight here and its 13th fight overall, Barróg was in the best shape it had ever been in.

https://i.imgur.com/fEcTPpl.jpg
A shot of Barróg before going into its Top 8 fight.

FIGHT 7: TOP 8

So for the top 8, all the fights were randomly drawn. I was expecting to fight Shrapnel originally, but I ended up getting paired with the winner of the second losers melee, which just so happened to be... DB12... again. Pretty crazy coincidence, but I had my strategies for them, so after testing the new drive settings in the arena I was ready to fight.

https://www.youtube.com/watch?v=zEys9L1Gr7U

Some observations from this fight:

• I intended to get out of DB12's charge, but unfortunately the machine wasn't as fast as I'd hoped, and DB12 called by charge angle.
• It's at this point that I go flying well into the corner. I do find it interesting that I didn't seem to get much vertical height, my theory on this is that all the weight is at the back of the machine, so most big hits on the front can only roll me and send me into a tumble.
• After one big hit I'm in a position where I can't self-right, and my batteries are hanging out. It doesn't take a genius to know that I've lost this before it even started.

POST-FIGHT:

https://i.imgur.com/rliKSUc.jpg
A shot of all the damage from the hit. Note the crack running all along the top piece.

Well that fight was certainly a bit of an anti-climax, but nonetheless I was satisfied with my performance at KOB UK. Damage wise the hit bent one of the wedgelets, and a crack was formed all along the front piece of the machine, arcing back as far as at the top. Annoying damage, but not irreparable, and so being out of the competition now, I set my sights on one more fight.

FIGHT 8: GLADIATOR

https://i.imgur.com/TdGjxrf.jpg
Barróg loaded up into the arena.

So the gladiator was one of the fights I absolutely wanted to be a part of when coming to KOB UK, and thanks to my early finish I had enough time to repair and prepare. A support piece was installed underneath the front piece to keep the whole thing together, and wedgelets and batteries were replaced. I had hoped to be a part of a tag-team whiteboard with Orpheus, but unfortunately there were horizontals in the arena, and I wouldn't have time to switch between my setups quickly enough. I loaded into the arena and prepared for the mayhem.

https://www.youtube.com/watch?v=V0SfiMgxkFg

Some observations from this fight:

• The first part of the fight was me trying to stay by the sides, which seems to have been an effective strategy. Neon was my biggest fear early on, but unfortunately for Ellis Neon didn't seem to be spinning that fight.
• I finally manage to get a solid lift on DB12, sort of a last hurrah for our rivalry if I do say so myself. I can't quite get them into the pit, but the bot seems to die shortly after. In its defence, this was its 11th fight, and 4th fight that day alone, so a bit of wear is to be expected.
• For the second part of the fight, I seem to want to fight Binky instead of, y'know, anyone else who couldn't kill me. In my efforts to get around Binky, I ended up feeding them into Impact and Bane, disabling both, so you can't say that there's no strategy involved.
• For whatever reason Binky is really able to do quite significant damage to Barróg like none of the other verts I've faced so far. First it removes one of my claws in Manchester, and here it knocks out two of my wedgelets, corresponding green pieces included, and for the first time so far Barróg takes a direct hit to its base. Fortunately, the curved nature of the design and the weight distribution allows me to roll right back onto my wheels. Nice to have that part of my design vindicated, if only once!
• I'm definitely driving a lot better in this match overall, with oversteering being kept to a minimum from now on. Using my newfound control, I'm able to stay out of much of the danger until there's only three machines left: me, Aegis, and Binky.
• At this point the fight is half me and Aegis trying to work together to disable Binky, and both of us cheekily trying to feed the other into Binky's weapon. This goes on for a few minutes, but eventually Binky starts running out of power, and a well placed lift by Aegis sends it over and out of the running.
• Aegis, last years gladiator winner, was the largest souce of inspiration for Barróg's design, so it seems that this style of bot is pretty darn resistant. We were both too awkwardly shaped for each other to really use out weapons, so what resulted was a pushing match for the ages. Barróg's general wedge shape was more suited to getting under Aegis, but only where the remaining wedge was, so pushing matches were still pretty even.
• Near the end of the fight, Aegis wedges me onto the side wall. Thanks to the plastic nature of the bot, I'm just about able to bounce out of there, and I gotta say, it was pretty nice to hear the crowd cheer at that point, even if it was only for another 30 seconds or so.
• Finally, after over 9 gruelling minutes, Barróg loses drive on one side. This is to my knowledge my first and only electrical failing in the entire tournament, but I am willing to let it slide since the machine has gone above and beyond what would be reasonable asked for it.

POST-FIGHT:

https://i.imgur.com/JKzHRkH.jpg
Barróg, essentially in the condition it's still currently in.

So I was pretty happy with just how long Barróg seemed to last, and congratulations again to Rory Charlesworth and Aegis for two back-to-back gladiator wins! I took a look inside the machine to check my batteries and see what had caused the left side drive to fail. My batteries were hovering around 14V, and as it turns out, it was the fuse protecting the left side ESC that had failed. Once I replaced the fuse the machine was still perfectly functional, which was a pleasant surprise! Maybe a disappointing way to go out for some, but I was just happy to keep my BotBitz 30A working, and second place in a gladiator is a pretty significant achievement for me, certainly my favourite fight of the event.

https://i.imgur.com/yl3j0e7.jpg
The 30A fuse that blew, can't fault it for doing its job.

POST-EVENT THOUGHTS

• All things said and done I was pretty happy with how well Barróg held up, doing far better than I ever thought it would. The machine really seemed to finally be in a polished state, and as far as I'm concerned this is as far as the machine in this state will ever be able to go.
• Mercifully, with the exception of the fuse blowing near the end and a few radio glitches, Barróg went through the entire event without any mechanical or electrical failures, which may be the happiest result from the tournament. Putting loctite on the reverse threaded screws holding the wheels in seems to have solved my wheel problem, and my 4 inch wheels were light, sturdy, and had plenty of grip. I never flew up high and landed up on the wheels, so shocks from that may break them, but for now I'm sticking to this technique. No ESC's blew as well, and my batteries kept pumping the whole event.
• Barróg's greatest asset was its shape. thanks to the plastic construction, geometry, and weight distribution, it was able to counter many things vertical spinners could throw at. A surprise to be sure, but a welcome one.
• I'm still surprised that I was able to finish Barróg in the time I did, especially since I was working on a beetleweight simultaneously. I seem to be able to work pretty quickly with plastic now, and I'm excited to push my construction methods even further in the future.
• Barróg's two greatest weakness was its self-righting capability and its weaponry. There were still positions where I wouldn't be able to self-right, and despite getting a few grabs in, my claws and lifter weren't really all that effective. I have ideas to improve the latter in the short term, but self-righting capabilities would take a complete redesign, probably in the same style as a roll-cage like I currently have at the back.
• A second Barróg would definitely require a complete weaponry redesign that would be faster, more effective at controlling other bots, and be able to self-right from any angle. I have some ideas for this, but I'll save them for a seperate post later on once I've finalised my CAD's.

All in all KOB UK 2018/Insomnia 63 was a great time for me, and I look forward to returning next year with an improved bot. Originally my next intended event was Robots of Destruction 2019 in Dublin, but unfortunately that event has been cancelled, so now I'm looking to enter the Robodojo full combat event in January. I'm entering full combat instead of sportsman since A) sportsman is full of lifters, and since I have self-righting issues, that may be a liability for me, and B) I want to keep testing the current chassis against as many spinners as possible, to confirm my theories. It would also be great to fight a working horizontal to test that configuration. As well as Robodojo, I'm attempting to organise a Bodgebot antweight event at my university in Dublin with the Elecsoc there, so we'll see how that goes as well.

Thanks again to everyone who made KOB UK possible, as well as all of the roboteers who competed. I had the time of my life at the event, and it's been great to get so many people messaging me about the bot, particularly from people from Ireland who've been showing interest in starting out. Here's hoping 2019 is just as good for me and robot combat in general!

https://i.imgur.com/NkoEAnM.jpg
Me and my dad in the car waiting to board the ferry back home. We decided to use this opportunity to catch up with Battlebots 2018!

Hey Eoin. Just wanna say Barrog did phenomenally well, especially for a relative newcomer & was definitely one of the bots I was rooting for. It was a shame that the one fight that DB12 beat you was the one that was straight elimination.

So thanks to the Christmas season, I finally have enough time to CAD up my next FW and the second model of Barróg, one I'm dubbing "Barróg Doom" (name pun from "Dearg Doom" by The Horslips). I was debating creating a new build diary for this, but given how the description "Featherweight Lifter" still applies and how I'm quite proud of this build diary itself I'll stick to this one for now.

https://www.youtube.com/watch?v=y5G8AJf4Xzw
The cracking song I'm taking the name of the new machine from.

Barróg surprised me in a lot of ways, and after a year's worth of events I had gotten a lot about it tuned in. I had a sturdy, reliable drive, and a body design that seemed to absorb and deflect damage in all the right ways and areas. The one consistent issue with the design however was the weapon; it was slow, bulky, and never really grabbed anyone. This new design is essentially the same as the first iteration, but reworked to allow a Snake KOB-style grab-and-lift mechanism.

https://i.imgur.com/jgcf2Vc.png
The new design, minus the inevitable weight-saving holes.

Design-wise almost everything will be the same. The base and walls are still 10mm HDPE and will still be mounted with barrel nuts. The drive will still be powered by four 12V motors with tapped 100mm plastic wheels, running on a 5S battery. The machine is still shares the same length and width as before, and the overall geometry will remain the same. I'll even be able to re-use the existing anti-horizontal wedge with minimal modifications. To figure out where to place the new height, I just looked at where the gouges from previous verts stopped, then went a cm or two higher, a very scientific method. Weight-wise, it should be looking far healthier than Barróg once the gears and sprockets bought from beltingonline.co.uk are machined, the machine doesn't gain too much extra weight with the new setup compared to the linear actuator, and losing some of the material on the top goes even further with this. The smaller size and weight allows me to also run with rollcages on the sides, so the machine should now finally be able to self-right from any angle.

https://i.imgur.com/2TwF0kG.png
A look at the insides.

The lifter operates similarly to the FW lifters used by Snake (CHN) and Mantis (UK). Upon power, the lifter gear on the clamping arm comes down. Once it catches, the teeth engage with the main lifter gear, and both the clamping arm and the lifting forks raise up. This allows for Complete Control-style lifts while only requiring one source of locomotion. I'm planning to use some hollowed out 25mm steel pipes for the main axis of lift, and have already reached out to Giles Ruscoe (builder of Mantis) about his methods.

https://i.imgur.com/Iqejkgx.png

https://i.imgur.com/KlYpIoT.png
My mockup of what the sprocket mount should look like. Needs to be tight, as given threads are holding it on to the drill motors, any gaps will cause unscrewing and a loss of essentially half the power.

The power for the lifter will be provided by two Argos 14.4V motors opposite to each other on a sprocket, similar to the system of transmission on the FW bot Nessie. They will be held tight in together by a system of tapped hubs and reverse threaded screws. Using the Argos drills gives me a system that's affordable, easily replaceable with the parts ready to buy almost anywhere in the UK and Ireland, and come with a built in torque limiter, which should protect my parts from destroying themselves at the peaks of their output. It goes from a 12T sprocket to 29T, then from a 16T spur gear to a 48T, a reduction of 206.19:1 per drill motor which should provide in theory a total lift of 22.185kgf/m, plenty to lift a standard FW, and a lot quicker than the previous method to boot.

https://i.imgur.com/FNNcNUg.png
A better look at the systems of sprockets and gears.

I still intend to run the original Barróg from time to time, and will bring it with me to Robodojo later in January (hopefully I can fix the linear actuator in it before then). I am hoping to get this new build finished before Extreme Robots Bolton this July, with the intention of getting any kinks sorted out before Insomnia 65. If anyone has any thoughts on the design then that would be appreciated, I'm keeping most of the complex stuff in the weapon this time round, so the rest of the build should be easy in comparison. Some methods of securing the main lifter gear to the axle pipe would also be very useful. I'm also looking for a way to mount the green HDPE wedge that maintains some of the springiness from the linac version, as I believe that was key in letting it survive the blows the way it did. Suggestions for that are welcome as well.

Barróg was exceptional for a first featherweight bot! With this new iteration, it seems you are building on what already worked and improving what didn't, whilst keeping the character and distinction of the first build. To me, this has all the hallmarks of potentially another great bot.

Let this be a lesson for other new builders: this is how you do incremental improvement well :)

So Robodojo January 2019 has come and went, and was a fantastic event overall, but before I get into the fights I'd just like to get into some of the repairs that had to be made between Insomnia and Robodojo. First of all was needing to get a new green top cut for the bot afting using up my spares at KOB UK, nothing too fancy needed there (at this point, I've accepted I'll be going through one of these per event if spinners are involved). Second of all was repairing my broken linear actuator; when testing the linac for the first time months after KOB UK it seems a bolt came loose within and ruined two of the nylon gears within. Fortunately Gimson Robotics sent over some replacements free of charge upon contacting them, so all it took was some reassembly and some loctite for insurance and I was good to go. The horizontal configuration for the machine was also prepared: I knew Telekenisis would be there, and wouldn't want to chance facing them without it.

https://i.imgur.com/IYa0XbT.jpg
A shot of the busted gears in the linac. fortunately the pieces were easily replaced.

ROBODOJO JANUARY 2019

Getting to the event was far more comfortable than previous excursions to the UK. By going to Liverpool over Holyhead, the drive to the event was not only shorter, but due to the increased length of the cruise we were actually able to sleep on the way. We ended up being one of the first teams to arrive, and ended up sharing the same table with Colin and No Imagination and Chimera's Revenge, and Alice and Tantrum. The machine was given some last minute touches, and was at 100% health going into the main tournament.

https://i.imgur.com/nmDa7u2.jpg
A shot of Barróg, probably the best it'll ever look.

ROUND 1: FORGE MASTER

The format had been announced a few days before the tournament. Both the Sportsman and Full Combat contestants would take part in four 1v1s with other machines in the bracket, drawn at random. For the first round I was drawn up against Mark Smith's Forge Master, an axe-bot that made it to the top 20 at last years Insomnia. I knew it was a sturdy bot with a lot of experience of driving for the short time it's been active, and that weapon could cause cracks in the HDPE if it hit the right spots. I knew it would be a control match over all else, and those hinged forks would beat the HDPE wedgelets in head-on collisions, so I opted to use the 1.5mm stainless steel wedge instead. I loaded up the bot and got ready to fight.

(Thanks again to Cosmin Gorgovan for filming and uploading all the fights, the recordings of which I'm using for this post)

https://www.youtube.com/watch?v=Lw8AchEobXU

Some observations from this fight:

• Forge Master seemed to be having issues with the axe beforehand, so believing it wasn't working, he just left the cover for the axehead on. Eventually the axe seemed to work later on, throwing the head off eventually.
• The metal wedge performed beyond my expectations in this fight, and seemed to take priority over the forks more often than not. I'm crediting this to having more weight on the end. As someone who's seriously looking into the idea of hinged forks, this something I'm keeping in mind for the future.
• Eventually I corner Forge Master and get a really good grab on them. For the first time in what feels like forever, the weapon is working as I originally intended, grabbing tightly, and allowing me to drive with them on top. Unfortunately, the pit ended up not working for this fight due to damage, so I was unable to get the pitting I was hoping for and end up having to let go shortly after.
• From this point the fight is mostly just a back and forth shoving match with me possibly having the slight edge due to size. Eventually though Forge Master takes a thwack that seems to kill the receiver. It seems that earlier problems with the bot could also be attributed to this malfunctioning part.

POST-FIGHT:

It's always good to start off a competition with a win, and thankfully the machine seemed almost unharmed. One corner of the steel wedge was slightly bent, but easily fixed, and there was a small crack on one side of the chopping board near the lifter, but with none of that looking to be too bad I just swapped out my batteries for the next fight.

ROUND 2: X-303

For the second round I was dealt a far deadlier opponent, Cosmin Gorgovan's X-303. This drum bot had come off a relatively disappointing performance at KOB UK to go on undefeated and win Dutch Robot Games 2018, so the bot was no joke. I didn't really have any configurations planned against drum bots, my only prior experience was with Drumroll at XR Manchester 2018, so reasoning off the fact that the plastic wedgelets would be torn up and the horizontal configuration would just give him something nice to bite onto, I opted for the steel wedge and went in with a strategy to finish the fight as quickly as possible.

https://www.youtube.com/watch?v=VP8nEVhiq_A

Some observations from this fight:

• Fairly happy with how quickly I was on X-303 at the beginning, my style of trying to stay in the face of spinners as much as possible left little room for the drum to get a truly good hit in at the start.
• All of the hits taken at the front of the machine, while damaging the wedge further, never launch the machine that far, only lightly lifting it. Again, I owe this to the peculiar weight distribution on the bot, which is a great strength except when...
• While trying to correct my driving, I end up oversteering a little too much, which reveals the back of the bot to X-303 for just a second, which is just enough time for it to get that perfect hit and send me packing out of the arena for the first time ever. At least it's hard evidence for my weight theories though!

POST-FIGHT:

A very exciting fight for basically only being 30 seconds long, and in retrospect it was probably good the bot got off with that little damage, things could have certainly been a lot worse had the fight gone on longer. The metal wedge up front was at a 90 degree angle and messed up (a good gift for Cosmin at least), but other than that no major damage, which was a relief as all I'd need to do is some TLC for the green front and charge some batteries and I was good to go for the next fight.

https://i.imgur.com/00WVRmU.jpg
A shot of the wedge post-X-303. The left holding bolt seemed to almost be fused with the plastic, so it took a bit of fiddling to get it out.


https://i.imgur.com/ExDsCHQ.jpg
The back of the bot where it was hit. Though it isn't very clear, there's a clear concave mark left in the back where the drum made contact. No damage to the securing bolt or the linac though, which was surprising.

ROUND 3: PIP

My third fight was against Sam Graham's PIP (Pretty In Pink), a vert at its first event, and I believe the first event Sam had competed at as well. The weapon was certainly scary, but I knew from previous fights that the bot wasn't the most controlled, and once I heard he was removing the front wedgelets due to driving issues, I knew that so long as my front was facing his, the weapon shouldn't ever make contact. We prepared the plastic wedgelets as was the given vert strategy at this time, and entered the arena.

https://www.youtube.com/watch?v=TcJ5I7Wyoto

Some observations from this fight:

• My hope for the fight was to get in under PIP and grab him right down the middle, keeping my claws safe and granting me full control for a pitting. It seemed though that I'd need some speed to get under him fully.
• After some failed attempts I had PIP in a position where I thought I'd have a perfect grab, only to find out that I was just a little short. As it turns out though this meant the lifter could keep going up, and due to PIP's drive issues and Barróg's height, I realised I was in a position to score an OotA.
• At this point PIP tried spinning up and driving around the front piece, eventually chewing into my lifter claws, while I tried shaking him off. At this point the arena marshalls started to get nervous, as PIP leaving the arena in this state could pose a safety risk. In hindsight I should have gone for a different wall for the OotA, but at this point I just had my blinkers on and did not want this fight to go on any longer.
• Eventually PIP is told to spin down, and a few bumps later and the bot finally slipped off over the arena walls.

POST-FIGHT:

Certainly not a way I had ever intended to take a win, but I was always happy to have taken down another vert. Damage wise the bot had actually taken a surprising amount; my left front claw had snapped at one of the joints from an earlier hit, the right spine took quite an amount of cosmetic damage from the spinner, and for some reason the fuse for the left side ESC had blown. The last one was the most confusing, but nonetheless I replaced the claw and fuse, and got ready for my final fight.

https://i.imgur.com/xN5kO9j.jpg
The right side spine after what seems to have been a trip to the hairstylists.

ROUND 4: GRAFFITI

The final fight for me was at some point going to be against Get Shrekt, but over the event the Round 4 draws were redone, and I was due to fight against Will Owen's Graffiti. The stylish linac lifter had been doing decently at the event so far, and was currently 2-1, same as me, owing to some impressive driving. I decided to keep the plastic wedgelets to test them, as I'd never really used them against another wedge before.

https://www.youtube.com/watch?v=U8dz-vIBc_U

Some observations from this fight:

• From the start, it became apparent that his wedge was far more effective than mine, owing I'd imagine to the increased weight on it and the damage the wedgelets take over time. This put me at a disadvantage, further increased by Graffiti's excellent driving.
• Eventually at 40 seconds in I get a lucky grab and can once again do what the bot was always intended to do, bring an opponent to the pit. Barróg has "worked" more here than at all the other events I've been to combined!
• Unfortunately, thanks to some sloppy driving and fortunate weight distribution on Graffiti, the bot barely escapes out of the pit, and after one more failed grabbing attempt from me I've basically scuppered my last chance.
• The rest of the fight is a combination of me desperately trying to get around Graffiti and avoiding the pit. While I'm satisfied in my driving skill to avoid the pit in an arena that small for the full 3 minutes, ultimately I'm still constantly getting pushed around, and it goes to the judges.

POST-FIGHT:

So unsurprisingly the fight goes to Graffiti, which was absolutely well deserved. No damage was sustained minus some messed up plastic wedgelets. Barróg finished the tournament with a respectable 2-2 record, but I was here for data and fights over glory, and so while I was at the competition, I wanted to get in as many fights as I could, which led to my final whiteboard fight held after the main competition.

WHITEBOARD: BINKY

Binky, the vert that had dealt the most damage to me over the bots life, was at the show, but was a reserve. As it had not fought yet and I was hungry for more data, I offered a whiteboard match to the Botwrights, which they agreed upon. Usually I would use the HDPE wedgelets against verts, but after my confidence was shaken in them a little after the last fight, I decided to switch over to the metal wedge as I knew from Manchester that it could get under Binky, plus now I could properly test it against a vert in a 1v1.

https://www.youtube.com/watch?v=zADBe4aTSnA

Some observations from this fight:

• I got a nice grab on Binky earlier in, being able to use the bots weapon issues to its advantage. Unfortunately I overestimated the strength I'd need for a good grab, and all pressure from those good grabs earlier on in the competition had accumulated to causing the front to just snap.
• At least I was able to keep my grip on the bot, and managed to drive it into the pit, unfortunately slipping in a little myself. As it was a whiteboard though the pit was brought up again and the fight was allowed to continue.
• The next minute was me just trying to outmanoeuvre Binky, taking a few token blows along the way but for the most part surviving. The metal wedge is still doing good so far.
• Unfortunately at the two minute mark Binky gets a hit on the wedge, and the full force of the impact travels up the bot, ripping the wedge off, ripping the linac out, and leaving me stranded and left for dead. Fun to watch frame by frame though!

POST-FIGHT:

https://i.imgur.com/K9PiGTY.jpg
...oh boy.

So that fight was certainly fun, and I don't feel any shame in losing at that point after all I'd done earlier, but man that was the most violent hit the machine has received yet. The wedge was somehow bent in four directions, the green piece was now three individual green pieces held together by bolts, the casing for the linac gearbox was broken in so many places, and due to it being ripped out the power wires for the right side drive were all disconnected. I believe that the linac was ripped out mainly due to how instead of the green piece breaking off in chunks upon nasty hits, getting hit dead centre in the wedge transferred far more of the energy upwards, causing the casing break. The machine was done for today, but as it was near the end of the day that doesn't matter too much to me, and hey, at least the match was entertaining!

https://i.imgur.com/53wCmWr.jpg
The linac after the Binky fight. Gimson have informed me that they can repair this, which was a relief to hear as this model is discontinued!

POST-EVENT THOUGHTS

• For another event, I haven't had a single wheel or gearbox break, which I'm happy with given how much the machine was tossed around this time round. Some of the wheels are more cracked than they were before the event, but given how much trouble I had removing a "damaged, weakened" wheel at KOB UK, I'm running these until they break. My current drive system then is still powerful, cheap, relatively lightweight, and very easy to replace, which is a dream for me after issues at earlier events.
• Thanks to how many different weapon types I've fought, I feel that I'm finally able to safely determine what configuration I can use for which weapon. Those are:
  
  • HDPE Wedgelets: Verts
  • Steel Wedge: Drums, Wedges, Axes, etc.
  • Hardox Wedge: Horizontals

Drums are probably still the largest guess for me, but I may have plans for them in the future, and hey, at least I can still do decently against verts, which to me is the greatest success of Barróg.

• Despite beating Forge Master's forks, I do think that having metal hinged forks would be sensible for Barróg Doom, possibly jutting out from underneath the front and with some downforce on them.
• After some conversations from other builders, I'm fairly certain the HDPE chopping boards I've been using have actually been LDPE, or at the very least a recycled, weaker version of HDPE. While this should be bad, the shattering nature of the boards may have left me in a better position against some of the verts than proper HDPE would. I'm definitely debating whether I should switch for Barróg Doom or stay with what I have already.
• It was nice to finally have my weapon validated in its effectiveness! Practice and small improvements would be needed to avoid all the self-destruction the machine inflicts upon itself, but hey, small steps. Still switching to the new lifter setup however.
• One reason the green front may have broken is because the lifter bracket spacers weren't being used, which meant that almost all of the forces exerted by the linac were going to the chopping board instead of the lifter spines. Some spacers or a modified lifter bracket could go some way to avert this, which I may use for Robo Riots Dublin which should be happening this coming June.

Robodojo was great fun, and I learned a lot that should be very useful for the coming build. An Irish competition to replace Mechatrons for 2019 was announced a few days ago, and I intend to have Barróg Doom up and running for the show, though I'll probably bring the original Barróg regardless. Cheers to everyone who was at Robodojo, I hope to be back in the UK soon!

I want a rematch with FM working!!! XD the RX had lost a Surface mount resistor which i believe what was causing the issues and may have lead to BOTH BECs in the drives ESC dieing (even though only one was connected) resulting me stop moving. But great to see the Jolly Green Giant kick ass and take names

Great writeup of the event and well done on your performance. Seems like your weapon takes a lot of finesse to make it effective and it was great to see it work (and then sad to see it destroyed...). That's great that Gimson can fix the linacc, you don't hear of companies repairing small items like that very often (I once tried to buy a spare part for a £20 food processor and the cheapest I could find it was £25... :roll: ).

I was wondering if the chopping board might benefit from some reinforcement, perhaps some ribs/stringers running along the underside? That should make it less likely to start drooping if/when the weaker plastic gets damaged.

Clearly eion needs more penny's XD but srsly chopping boards behave very differently compared to HDPE. It much more brittle where hdpe bends more then shatters e.g. Gabriel valley carbide. Reason why we love it
Absorbs a tonne of energy

So this quick update is mostly to ask about gears, sprockets, and how to mount them, but first, an update on the new machine. Barróg Doom should be constructed a lot quicker than the original, with the base, back and sides being cut in the 30 minutes I had free last weekend to work on it.

https://i.imgur.com/v5JECzK.jpg
A shot of the new walls, placed next to one of the old ones to give a sense of scale.

My main question to all of the builders on the forum is on the matter of mounting sprockets, gears and axles. I've purchased all of the relevant gears and sprockets off of Beltingonline.com, but I was hoping to ask for advice on how to mount them. I'm planning to use 10mm rods for all but the largest gear, which I was going to use a 25mm steel pipe similar to Giles Ruscoe's Mantis. What are common ways to mount these gears to the axles, and how to mount the axles to the bulkheads? What steps can I take to avoid the gears from misaligning? Should I use bearings and, if so, what kind? What would be the recommended way to machine these parts to minimize loss in strength while improving weight efficiency? Should I use the 10mm rods, or go up, or even down?

Any help people can chip in with this would be much appreciated, thanks in advance.

https://i.imgur.com/eIRZdX3.jpg
The parts in the flesh. Definitely bulkier than they need to be, but it's in how much should be shaved off that I don't know.

https://i.imgur.com/thpqhsJ.png
All of the parts seen from an angle. I'm thinking securing the sprocket to the small gear may be good, though space would need to be left of course for the chain.

https://i.imgur.com/K7mb6fF.png
A side on view of the transmission system.

Quote:

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What are common ways to mount these gears to the axles, and how to mount the axles to the bulkheads? What steps can I take to avoid the gears from misaligning? Should I use bearings and, if so, what kind?

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There are two kinds of shafts. There is a dead shaft, where the shaft is static and the gear slips around the shaft or has bearings inside the shaft to allow it to roll and then there is a live shaft, where the shaft is mounted by bearings on either end and the gear is fixed to the shaft. In Kaizen and Jibril, the axe is a dead shaft but in Jibril's drive system, it is a live shaft.

The material that the shaft is mounted in is important too. HDPE deforms way too easily (though I will confess, Kaizen's axe was a dead shaft in HDPE with a cap on one end to prevent it falling out).

The gears I have come with grub screws in them which I drill a indentation into the shaft and then threadlock them in. If yours haven't, I suspect welding it would be the best option.

Given your design, I would go for a live shaft for your first stage, mounted on flange bearings (https://www.gearsandsprockets.co.uk/...lock-bearings/ for example) and then perhaps a dead shaft for your final stage to the arm but, weight allowing, pillow bearings might work here.

Quote:

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What would be the recommended way to machine these parts to minimize loss in strength while improving weight efficiency? Should I use the 10mm rods, or go up, or even down?

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10mm rods are OK in my opinion, depending on what it is made out of. I would have said a lathe to remove some of the bulk from the gear hubs would have been the way to go on losing weight.

Always make a cardboard or wooden template first and its a case of just being precise with your markings. Noting I have never done a chain drive, the sprocket and chain needs to be perfectly aligned so I would mount your motor with the sprocket on first, measure from the edges of your robot as to where the sprocket is horizontally and then mount your second sprocket on the subframe to line up with the depth of your first sprocket.

So if, after being mounted, the motor sprocket, from the far left edge of your robot, is say 280mm in, the second sprocket also needs to be 280mm in. I am sure others who have done a chain drive before can advise further.

Lathe to remove weight from the gears sounds like a good plan. It's not the most efficient in terms of strength-to-weight ratio but it does mean you keep everything symmetric. I guess drilling holes would maintain more strength for the same mass reduction but unless you get them really accurate you might end up with some wobble. On the other hand I'm not really sure how much a problem a bit of eccentric mass would be when you're reducing the rotation speed so much...


I was wondering if could be worth you putting in some kind of direct solid connection between the motors and driven sprocket to keep them aligned? As it is, you're going from the driven sprocket, down the mounting bracket, then along the base to the motor (potentially also having to measure out to the edge then back to the motor). It seems like there's a lot of room for measuring/marking errors, and for things to flex in operation, which could leave you with misalignment and derailed chain, one way or another. A bracket that goes straight from the motors to the first driven shaft would give you a nice direct load path and minimal scope for error in manufacture. Might even be worth moving all the motor mounts onto the weapon bracket for the same reason.

I'm loving the new design - it's really clever bit of mechanics to double up the lifter/grabber function. Looking forward to some more updates!

I spare weight by drilling holes in the gears, if they don`t turn as fast as a couple of rpm it should not be a problem.
You have to leave a couple of mm material around the holes.