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Thanks a lot for the reply! Was very helpful :) Just one quick question, did you wire it up the same as a drive motor (forward on the stick changes speed) or did you do like a servo type setup (stick position is the same as axe position)? (Hope that makes sense!)Quote:
Originally Posted by Roboteernat
Thanks again :)
EDIT: Just found your test video on you forum post lol it looks like you are doing the former xD but if you could confirm would be much appreciated!
I understand.
I had no feedback from the motor position, so stick forward is drive motor forward, back, drive motor back.
The only thing stoppuing it from going further was the chassis/floor.
a video of it running is on the build log: http://www.fightingrobots.co.uk/thre...ld-of-fw/page8 first post on page 8.
Im using a servo tester to control the motor ESC so i didnt have ti wire in the TX.
EDIT: just seen your edit and that you found the vid :)
Thanks a lot :) You have been awesome :)
Can i just ask one more thing, did you use a brushless or a brushed scooter motor? I don't mind getting a 85A ESC of either type but just wanted to make sure which was best for the axe xD
Thanks again!
You are using a brushed motor for the axe, so you can either use an ESC for a brushed motor or use an ESC for a brushless motor and change the firmware so you can use it in a brushed mode.
Hello everyone!
The robot is really coming along now and with loads of great advice from Roboteernat its finally nearing completion xD
Just a few questions remain which i would love to get all of your input's on! :)
Firstly I have read that Hardox 450/500 is the go to for a hard wearing axe head so I would like to use that but I just wanted to get your opinions on what design i should use? Is a hatchet style blade beneficial verses a pick axe style blade? I would have thought a smaller point would pierce better but I see a lot of robots going for a wider blade. Your thoughts?
Also along that train of thought, Is there anything i should be aware off when using something like Fusion 360 to design the blade and export it for cutting? (also any recommendations on where to go to get it cut? xD)
The other thing is I went with the BotBitz 85A ESCs and I found out from Roboteernat that the original ESC these are based off of has been discontinued. I hear the FeatherTwo's from Rory are pretty darn good so i was pondering switching the ESCs out for a FeatherTwo and using the one BotBitz to drive the axe motor.
Again any thoughts/recommendations on that idea and other brands of ESC?
I will post a link when i upload the latest video of what im doing too if you guys are interested :)
Thanks in advance!
Will :)
about the Head styles, they each have benefits. a point delivers the energy to a single point allowing you to make holes in materials but will wear quicker than other styles. a bladed axe (like Terrorhurts) has a smaller point to deliver energy to and will wear better than a point but it will not make holes. A hammerhead will wear the best but will deliver the energy to the larger area. TBH design something that looks cool or fits the theme of the bot (for me a hammerhead)
About Speed controller, a BB80 may be your best bet now as Rory has stopped making the single channel feathertwos, and getting a duel version to run the hammer is a waste.
Thank you for the advice xD i think i will have a play tonight :)
And i was actually thinking of using the dual FeatherTwos for drive and switch out the BotBitz ones and re-purpose them for the axe. What do you think? I shall also look at the one you recommended thanks! :)
Sorry to be a pain! but do you have a link, I am struggling to find the controller you recommended :(Quote:
Originally Posted by Maxamuslead
Thanks again :)
Hello everyone :)
Unfortunately due to not being able to get a suitable speed controller in time I have decided to just make a push bot for the Cheltenham Extreme Robots to get a bit of experience and know what to expect for the next one. I do have some ridiculous ideas in mind though for decoration so watch this space xD
Just a few questions about safety. Firstly, I know the robot must have an LED on show when its on but I'm curious to see what some of you guys have done for yours? It's running off a 6s LiPo so regular LEDs would just fry but I saw in a YouTube video that Angus (now part of Makers Muse) used a connector and plugged it onto the Spektrum receiver with a resistor in line. I'm not really sure if this is a good solution or if there is a simpler one out there?
Secondly, Where abouts have you guys put your removable link? I know it needs to be able to be put in and pulled out with the robots top on (giggidy :p ), but I'm worried about it being pulled out mid battle. Having said that the loop on mine is rather long so is this just as simple as making it shorter? lol Would love your feedback :) Its going to be a fairly boxy robot because I plan on using the base and top panel again in the final axe robot so i was thinking of maybe putting it in the same place as Crabsolutely Clawful on the back wall of the robot?
Again any suggestions is most welcome and thanks a lot! :)
Will :)
For my Middleweight, I wire two LEDs in series directly into the main power wiring, each with with a 24v resistor in them so that each only uses 13.2v (from my 8S LiFe setup).Quote:
Firstly, I know the robot must have an LED on show when its on but I'm curious to see what some of you guys have done for yours?
I put mine on the top of my Middleweight, works fine though I have a short loop and some raised side armour to prevent robots directly attacking it. On my featherweight, I put it on the rear, at the top of the robot so whilst you couldn't directly attack it, it would get damaged if flipped on its back.Quote:
Secondly, Where abouts have you guys put your removable link? I know it needs to be able to be put in and pulled out with the robots top on (giggidy :p ), but I'm worried about it being pulled out mid battle.
Yeah, using a standard LED, you can add in a resistor to reduce the current to stop it from destroying itself. Ebay has lots of prewired 24v leds that have the resistor and series wired leds.
I used a strip of Leds and then placed it inside the bot and used some 10mm thick acrylic as a guide pipe to illuminate an exposed section of my frame. Worked well.
Sorry didn't see your last reply. THIIS https://botbitz.com.au/collections/f...eed-control-v2
Unfortunately they are out of stock so best chances of getting th axe working would be either buy feathertwo single, tz85 or bb80 of someone which will definitely work and run all day everyday. Or using a 30a you ESC which should take it but will not be as happy
Awesome thank you, i didn't know that was a thing :)Quote:
Originally Posted by Roboteernat
No worries! I ordered one of the replacement 80A BotBitz ones but wont be here in time so I'm going to build a ridiculous looking push bot for experience xDQuote:
Originally Posted by Maxamuslead
Hey there Will. Regarding links, what I've done on both my FW's is bury the link connection a couple of inches deep within each & attach a cable tie to the loop on the link so it's much easier to pull out without risking the wire getting damaged.
On Neophyte, I've also made a small HDPE flap held on with tape on one side so it can stick to the armour, but still be opened & closed easily by hand. Blacksmith hit the cap with it's axe during one fight, taking the cap off, but in the process saved the link itself (I wasn't using the cable tie method then).
Regarding specific placement, I'd personally recommend placing it somewhere towards the middle or the back of the bot, making it as difficult as possible for an opponent to reach. I wouldn't worry too much about random knocks taking it out, as long as the connectors have a good grip you should be fine.
Thank you for your advice :) The cable tie idea is a good one!Quote:
Originally Posted by James Williams
Hello again everyone!
It's been a little while since I've been able to get on but the Cheltenham Extreme Robots show which seemed so far away went extremely well!
Big thanks to my brother, my friends Jon, Nathaniel, Dave Paul, Matt Andy and Joe for getting me through the event!
Here is the build video and part 2 is the actual event in case you want to see :)
https://youtu.be/eIWPur0QD8I
The main problem from the event was that I had two motors fry themselves and a gearbox is also toast now lol I learnt a hell of a lot about motors and gearboxes and how they fit together etc. So my question would be is there a way of having a more robust drive system then attaching the wheels directly to the gear motors? This worked well but as you can see in the video, wasn't all that strong compared to the other robots there. Would it be better to have a chain driven drive for example? Also I have been looking at the P60 gearboxes for more strength also, any thoughts? Andy mentioned Johnson 600s too?
Thanks a lot everyone as always xD
All the best
Will :)
You could drill through the shaft where the wheel overlaps and put a bolt and nylon nut on it. I ended up having to do this with another robot at EXR Manchester to keep their wheels on but it works.Quote:
So my question would be is there a way of having a more robust drive system then attaching the wheels directly to the gear motors?
For general power, what sort of voltage are you running this at? P60 boxes are generally quite strong (all metal affairs as I recall) but if you were after a simple solution as the box would need to be assembled, Gimson sell a neat geared motor for about £50 which I've used before in The Honey Badgerquite happily (https://gimsonrobotics.co.uk/categor...tary-gearmotor). That comes with a 775 type motor that has plenty of oomph for the FW class.Quote:
This worked well but as you can see in the video, wasn't all that strong compared to the other robots there. Would it be better to have a chain driven drive for example? Also I have been looking at the P60 gearboxes for more strength also, any thoughts? Andy mentioned Johnson 600s too?
Thanks for the reply!Quote:
Originally Posted by Ocracoke
I'm using a 22.2v 6s LiPo with 2 BotBitz 85a Esc's. The motors are Rs-550s motors which I checked can handle 24v but maybe I'm just pushing them too hard? The pin idea is a good one! I'll try that because we did have a wheel come loose. I'm ok with a little complexity with gearboxes but I'm still rather new to all this lol. Would an all metal gearbox be tough enough to mount straight too then? Cus at the minute the wheels are screwed straight onto the original cordless drill gearbox.
Thanks again!
Will :)
Nah. If they are rated for 24v, the 22.2v LiPo and the 85A speed controller are more than enough. I've ran 4x of the Gimson motors on my middleweight robot Kaizen and that had enough grunt to work happily for a little while but couldn't take the pounding so often ended up blowing one or two after each event. Your arrangement is OK.Quote:
I'm using a 22.2v 6s LiPo with 2 BotBitz 85a Esc's. The motors are Rs-550s motors which I checked can handle 24v but maybe I'm just pushing them too hard?
It may be worth checking your gearbox at the moment to see if any of the stages are plastic. An all metal affair will be more reliable when it comes to a pushing contest or flooring it. However, pinning the wheel to the shaft will be the same regardless of the gear material because the shaft will be made of metal.Quote:
Would an all metal gearbox be tough enough to mount straight too then? Cus at the minute the wheels are screwed straight onto the original cordless drill gearbox.
Love your videos Will, and the glitter!
Was the "spike" meant to look that rude? :mrgreen:
Thanks for watching! Sorry about the slow reply!Quote:
Originally Posted by McMullet
Not intentionally but it did end up that way a little ha ha. The idea came out of sheer desperation because I wanted to compete in the event and couldn't get the axe on Caractacus finished in time lol so wanted the daftest idea I could find and that was it xD
Thanks a lot for the reply! Sorry for the long reply, been one of those weeks!Quote:
Originally Posted by Ocracoke
That's good to know :) In your opinion then is there a more reliable way of mounting wheels other than pinning straight to the gearbox? I'm looking for the most robust thing I can find at the minute being as my robot currently only has a spike ha ha
Thanks a lot!
All the best ideas come from sheer desperation at the last minute! :mrgreen:Quote:
Originally Posted by willcaddy
I keep thinking about mounting wheels on separate bearings and driving them with a belt or chain, to minimise shocks and impacts getting to the gearbox bearings. That would seem like the best approach overall but it also feels like a lot of work compared to just bodging wheels straight onto the gearbox output shaft.
Short of welding the wheel to the shaft with a metal plate, the "pin through the shaft" idea is the best method I can think of. However, you could also drill a small indentation, attach a wheel hub onto the shaft and then screw in a grub screw into the indentation on the shaft (remembering to thread lock it) and then mount the wheel to the wheel hub. That is the method I use to hold down the pinion gear on my Middleweight's axe and has yet to come off.Quote:
In your opinion then is there a more reliable way of mounting wheels other than pinning straight to the gearbox?
Yea xD It turned out well though!Quote:
Originally Posted by McMullet
That's exactly what I have been thinking of doing but again not sure if it's worth it. I had an idea about mounting a bearing into the shell of the bot and having that connected to the other side of the wheel and attach to the gearbox like it is currently. Maybe that will provide some extra strength without building a whole drive train? Any thoughts?
Yea I think the pinning idea is the best one for me! What is your thoughts on a drivetrain? Worth it?Quote:
Originally Posted by Ocracoke
Technically the gearbox on your motors is a drivetrain. If you mean spur gears, I don't personally think it is worth it with the motors you have now. If you were running brushless or bigger motors, maybe.Quote:
Yea I think the pinning idea is the best one for me! What is your thoughts on a drivetrain? Worth it?
Yea, sorry I'm not very good with the terminology!Quote:
Originally Posted by Ocracoke
I mean just having the wheel separate from the gearbox maybe chain driven to take the strain of the gearbox itself from having the wheel directly attached. I'm just wary because the P60 gearboxs for example are pretty expensive and I don't want to break them every event lol motors are fairly cheap so I can buy loads of them.
Thanks again for being so patient and helpful!
No worries, gotta learn somewhere! ;)
Chain drive... Deathly Hallows did a chain drive for one of his Featherweights (and did a build diary here) which shows an implementation and I know at least Forge Master uses a chain for their axe. The trouble is that if you don't have the sprockets lined up right, the chain will come off.
I use spur gears in Kaizen's axe and for both Jibril's drive and axe simply because they are easier to get right than a chain. In the Featherweight category, Satanix uses a spur system that is pretty neat. However, this is all a bit of a muchness. I would personally stick with what you have for the moment and not worry too much about the gearbox.
That's great thank you xDQuote:
Originally Posted by Ocracoke
I'll have to see exactly what failed on the cordless drill gearbox and if it's a plastic bit I'll see what I can do about a beefier metal one xD Either that or maybe look for some cordless drills cheap and nick the insides xD I'll give some build diary's a read too!
Ah, I had forgotten one of your gearboxes has broke. I'd open it up and see what's going on in there first but for a replacement box, it might just be more economical to simply replace the gearbox and motor from another cordless drill, as you say.
Yea xD I shall try take a peak in the next couple of days and see!Quote:
Originally Posted by Ocracoke
I'm guessing it's harder to get the standard cordless drill gearboxes new? Because I haven't really found any online. I was thinking of looking around for cheap job lots lol
Thanks again xD
The odd thing, I find, is that I can't get the gearbox on their own. I guess it's probably more economic to simply get the whole assembly premade than it is to have the parts shipped in separately. If you do end up replacing the gearbox though, you will want a like for like replacement as so to match the ratios on the other side.
However, if the gearbox is bust because of a nylon gear breaking, it makes longer term economic sense to get a pair of motors with planetary gearboxes on them which are all metal, like the Gimson range.
Attachment 8706Quote:
Originally Posted by Ocracoke
I'm no expert but I do believe that gearboxes are supposed to have teeth lol
It appears when the motor seized or during an impact it sheered a few teeth lol but the gearbox (apart from the outer casing) is all metal and it wasn't a plastic part that failed which leads me to believe getting an all metal one wouldn't help unless it is a hardened tool steel one or something. So currently shopping around for cheap job lots of single speed, non-hammer drills. Whats your favourite site to get this stuff from? I'm currently looking at eBay, Facebook and Gumtree lol
Thanks again! :)
I've occasionally seen a joblot of "spares or repairs" drills (argos and others) appear on eBay. As Lucy says though, you need to make sure you have the same type all round or you'll go in circles.
If those are the three gears right after the motor that have broken, I would guess it's not down to the mounting. If it was the last set of gears before the output shaft that had died, or the output shaft bearing even, that would look like an impact on the wheel. I suppose maybe the motor slipped out of the gearbox (that happened to us several times at Robodojo), and then it span enough partially meshed to damage the gears?
I've had this happen to me with Shu! where the end stage planet gears just got stripped. It wasn't that the motor was being overvolted (it was a 12V motor running on 9.9v), it was the load on the end of the lifting arm which then got stuck as the arm tried to continue moving. Torsion did the rest I should think. I seem to recall the gears being brass, which yours does too.
Will, i may have some gears from some old drills i scrapped at work, will see what teeth they are and i can send them over to you if they match and if your interested :)
Thanks for the info! It was the gears closest to the wheel so I assume its just taken a big wack at some point in the final fight! I shall look around for some job lots xDQuote:
Originally Posted by McMullet
Yea, i was going a bit mad in the last fight because why not, its the last fight ha ha.Quote:
Originally Posted by Ocracoke
What are both of your thoughts on using a 2 speed gearbox (which doesn't have hammer) and just setting the speed I want? Its becoming increasingly difficult to find single speed drills that can cope with 22.2 volts! Also had a crazy idea of setting up a servo to select which gear i want mid fight lol but this might be a daft idea! what do you think?
Thanks again!
Will :)
That would be great! Thank you! Do you need any info like the amount of teeth etc? or is the pic good enough? Ill cover your postage too if there suitable! :)Quote:
Originally Posted by Roboteernat
Will :)
sent you a PM fb send me the details of the gear and i shall compare :D
Apologies for the slow reply again! But I have been doing a bit of digging again and its been really hard to try and find the right combination of motor and gearbox.
So my question is would it be OK to use a 2 speed gearbox and just select the gear i want to use and lock it in place? I mean i cant see why this wouldn't work but there may be something i have missed! Is the method of locking the clutch off the same for example?
The other idea i had was are the gearboxes from say the 12v variant (easier to get hold of you see) strong enough to take the abuse from an 18v motor? Obviously providing the shaft diameter is the same etc.
The only other idea i had would be to maybe get the P60 gearboxes and then buy loads of spare gears etc from them so if something strips i can just replace the gear rather than the whole box? What are your thoughts?
Sorry if these are a bit dumb dumb questions lol but I just want to make sure before i go down a particular route!
Thanks again everyone for being so amazing and patient with an idiot like me! :)