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Looking good, nice and compact, I think most FW machines have an approx. similar base size (mine is quite larger)
The only thing I'd be worried about is side and back armour...the material looks too thin judging from what I see on the cad, Earlier on you mentioned 20mm alu but it seems to be less at the wheels.
Other than that it looks solid.
That looks really good what will you make the chassis and bulkheads from?
Btw, what motors are they, as they look very short (in length).
Thanks! I did slightly misjudge a few of the sizes on the CAD, it should be around 15-20mm aluminium or hardox/aluminium depending on what's cheap/available! The innards and bulkheads will all be that 6082 aluminium I spoke about, again at about 15mm to make it all structurally solid, and I'm going to try to make the motor mounts also the inside wall/centre column to again try and make it that bit more compact.
One weapon I didn't post was the front-hinged lifter, which will be a similar design to the back-hinged - I'll be using that one most likely against any spinners that'd be able to get inside the machine when the back hinged lifter's up...
As for the motors too, they're supposed to be drills but I think I've misjudged them a bit. It was adapted from my original which had Banebots gearmotors on it, but they proved to be a bit too expensive so I had to adapt
Minor change to the machine, since I'm having to run on as minimal a budget as I can at the minute, I'm opting to go for just having two-ish weapons at GSL at the minute, the lifter(s) and my anti-spinner weapon. Which is actually just a more intricately designed scoop, but it sounds more threatening to be an anti-spinner device.
It'll still be built with the interchangeable weapons ability though, just the drum likely won't see the light of day for now since I can't afford the motor to run it. Truth be told, I'm still trying to get a spinner on there in the form of a cutting disc to create some sparks and hopefully slight damage to the tougher armours. More about the show appeal of it than anything else, but it's still all up in the air for now.
Also, a quick question for anyone who knows, would I fail a tech check for using a fuse as a removable link? I think I've queried it before, but I'd just like to double check before I design around it!
Fuses can double as removable link.
I hope they can too as I don't have space for both! I just hope that the connections are up to the high amps I will be pulling.
I found it easier to sort of focus on one weapon type per 'bot, I originally planned to have interchangable weapons and stuff n it was hard work. Your designs end up a compromise, n I thought well I'd probably be better dedicating and doing one thing well etc...
Fantastic! Just what I wanted to hear!
I don't see any reason why not from my own experience, they act the same as a removable link anyway, and they're a lot more solid than using a connector from what I can tell... not only that, but they're two in one, one less point of failure and all that.
@Daveimi, I would have done that too (what I did with HardWired I ) but I just thought it'd be a bit more interesting to use the whole removable weapons tactic. I am just sticking with the lifters for now for cost reasons, but I think there's something pretty fun about just being able to say 'I think I'll use a horizontal bar now' mid-tournament. The compromise makes it a lot less cheap, since I can't just design different machines and swap them out having been designed from the ground up for their weapon. I will say though, the lifter will be HardWired II's native weapon, just like how Tornado's 'main' weapon was the scoop.
It's actually been on the cards for a while, I wanted to make HardWired I, II, III etc. not actually progressions, rather just different types of weaponry - HardWired I would have the lifter, II would have a vertical spinner, III a crusher etc. That just naturally evolved into having a machine with the capability for all of them.
Perhaps it's me reverting to my five year old self again watching Robot Wars. "What's the best weapon for a robot?" "ALL OF THEM".
I've almost sourced everything for HardWired II, so the build will be going ahead pretty soon! Unsure whether to build the current version out of steel box section as opposed to paying a fair bit for aluminium I'm not even sure I can get cut and machined yet. Not to mention the risk of having it completely written off through a bad design. It's still on the cards though, if I can get it machined and cut by someone other than myself. The rest of the build is going to have to be hyper-budget too, in order to get to GSL if I get a place. Should be easily doable though now, since I've got all the electronics sorted and that's usually the most expensive bit.
Once I've got the shape and design battle tested, I'll be rebuilding it yet again to make improvements unless of course I get a good one first time, but that's unlikely.
Just as a side note too, purely out of curiosity, if I were to build an entire robot out of, say, meccano (but not actually meccano because that'd be way too weak) and completely rebuild the entire robot to form something of an entirely different shape using the existing parts, would that still conform to the removable weaponry rule, or would that be pushing it a bit?
HardWired II's coming on nicely. Well, I say nicely, it's not actually being constructed yet, though most of the components are on their way to being done. Got the drive and lifter linac sorted (I think) and the electronics are pretty much done too. I'm highly considering just running 14.4v for this championships, should be by far enough but mostly because I won't have enough for the 6s battery I'd prefer to have, assuming my drive will take it.
Main things now are:
A - getting the aluminium cut/machined to shape and size for the body and put together in such a way that it'll stand up to Little Spinner, 720 and the rest of the heavy-hitters
B- getting the bearings and the like mounted within a piece of aluminium side-armour for a bit more stability on the wheels, cheaply (going for 12mm axles and just getting the bearings into a 15-20mm 6082 T6 aluminium bulkhead instead of messing about with buying mounting blocks. May not be the best thing, but it'll be cheaper).
C- actually building the lifter/scoop - going for 25x25x3mm mild steel box section on this one, welded to a mild or stainless steel scoop for the actual lifting element. Would like a design that slopes down sharply, then evens out a bit so I can get underneath other machines a bit easier. Would have had a completely flat part, but it's probably not all too feasible given it'll be mild/stainless steel. If I had the money/weight allowance for thicker titanium or hardox I'd have gone for that, but for now it'll be mild or stainless, as thick as I can get it (aiming for at least 8mm to keep the spinners out, but may have to cut down). Would have gone for the 20mm aluminium again, but I really don't think that's the best choice given the thickness.
Unfortunately, these are the three most critical parts, so I'm either going to need to be extremely careful or get my University to machine cut a few blocks down. I have no idea how this is all going to work, considering my budget is literally depleted by this point for everything past the aluminium (hence going for things like mild steel) but I'm sure it'll get there. It better do now that I've already booked for the GSL Champs!
Do you have any pictures it sounds good.
I don't just yet, will be having some soon! Got some parts on the way, then I need to get some T6 aluminium and machine it down, somehow - (don't have money to have it machined down by another company or whatever :( ) then bolt it all together, stick a new receiver in there (Orange RX, hopefully failsafes with the DX5e I'm using) and the job's sorted!
What's that I can hear in the distance? Could it be...? Another major redesign?!
Well, sort of. Basically, the original idea was to go 4WD with a 4-bar lifter, which would have made the machine essentially a Featherweight Storm II, missing a wheel either side complete with Hardox scoop. Plans have since changed, and now I've changed to two wheel drive (beefy motors) with the same hardox scoop, both of which look pretty great (thanks, Maddox!)
In a nutshell, it's out with the 4WD for now, and in with a 2WD rambot, with most likely a back hinged scoop, or perhaps a small 4-bar IF I can fit it in there. If not then I'll re-evaluate to try and get some kind of lifter in there, for the simple fact that I think the lifter would work excellently in tandem with the push if I could work it correctly.
Here's a very quick paint image of what I had planned, http://i1355.photobucket.com/albums/...psf5abfbc7.png,
I've not ironed out the creases yet, nor really put any major thought behind it - I'm just waiting until I've got all my materials and parts here so I can cardboard mock-up the lot and see what I'm working with so that I don't make it massively underweight (not likely) or overweight or make everything the wrong scale...
Just thought I would post up the albeit somewhat limited progress I've made towards HardWired II being completed, since I had a spare few minutes to hand. Couple of weeks time, I'm hoping to have the whole thing built and ready to fight!
Also, as a little side note - what's considered appropriate protection for LiPo batteries? I have some 2mm Aluminium I could create a box with for it, and have it encased within the bowels of the machine, but I'm not entirely sure on the exact rules, since I've never managed to blow up a battery (thankfully!)
On the subject of blowing up batteries too, I'm rather hoping nothing of the sort happens at the championships - I'll have no spare LiPos!
Conscious of the fact I'm clogging up the forum with questions, does anyone happen to know what size bolts would be suitable for end-tapping 20mm HDPE together? I'm thinking M6, but I've never dealt with it before so I haven't a clue. Normally I'd buy a few different sizes and see what's strongest, but I've got no time at all to get it all finished! Going on with 20mm HDPE for the main structure now, end-tapping and bolting in some angled pieces of steel to give it a decent structure. Same goes with the baseplate, I'll be bolting that in too using a similar method. Top armour's likely going to just be aluminium, or whatever fits in the weight limit.
Aside from the point too, how difficult are 4-bar lifters to get right? I've got a basic idea, but the sizes of the arms are something I'm a little bit concerned about - I can move to an easier back-hinged lifer if needs be, however.
Do not end tap hdpe, it's too soft to tap into. Use L brackets
I see... Is there any way suitable to attach HDPE to HDPE directly as an aside to L-bracketing it?
Been looking at L brackets too, can't seem to find anything that'd stand up to too much force, I think the strongest I've seen are 150mm long by 26mm wide by 2.9mm thick... Might resort to having some made out of stainless if needs be, though that'd have to be a last resort because it'd be costly...
Just hoping to build something that'll stand up to at least a few hits with my downright appalling engineering knowledge...
You can screw it together, I did for many years. Not a brilliant solution tbh but it holds.
With conventional wood screws or bolts? I have to apologise, I've only ever worked with a solid body aluminium chassis, which was welded for me so I'm still getting my head around it, even though the championships are really quite close now...
May just wing it and see what happens. Probably going to go with some 50x50 2mm thick angle brackets and attempt to make my own angle braces out of scraps of wood or HDPE, using probably m6 bolts, if they're not too thin/thick. Then I'll just drown the entire thing in glue and hope it doesn't fall to pieces!
Woodscrews hold relatively well into HDPE. They won't always stop the pieces coming apart with a direct spinner hit but they will handle most knocks. Many feathers use this method.
I see, thanks! This is the first I'll have ever used HDPE, so I'm still a bit unsure of its properties.
The worry at the minute is, say, Little Spinner catching it just right and spraying my batteries all over the floor - I know that's a worry for everyone but my lack of spares means it's just that little bit more important...
Might give it a go when the materials all get here, see how it holds up to a bit of crash testing!
You will be amazed at how strong woodscrews into HDPE feels in your hands. It will feel completely immovable, because it is, for normal purposes. If you use big chunky screws, not too many but not too few, it will take some big hits to do major damage. And, if you're at the point of having batteries strewn across the arena, the opponent will have stopped hitting you. Gentlemen's agreement!
Also, pics as you build will help folks help you, regarding number and positions of screws and such.
I'm sure No Toy would disagree :lol:Quote:
And, if you're at the point of having batteries strewn across the arena, the opponent will have stopped hitting you.
Despite advice to the contrary (good advice though), I've edge tapped HDPE before with success. However instead of using a tap/die set, I just drilled a 5mm hole then drove the M6 bolts into the unthreaded hole and let it cut its own threads. The two downsides are that they aren't as dependable as threads in other materials and if you unscrew them/tighten them up a lot, they'll wear down pretty quickly too. But left to their own devices they're perfectly strong enough.
The other alternative if you don't want to use wood screws or L-angle brackets is to use push-fit brass inserts like these: http://www.ebay.co.uk/itm/M6-BRASS-I...item4cfe5c0c4a
Just drill an 8mm hole and hammer these in. It'll let you use bolts instead of wood screws and provides a good firm hold. If a spinner gets a good hit, it may well rip them out, but that is true of any fixing method if the spinner gets an ideal hit. You can always drill a smaller hole than 8mm and heat up the fittings so that they melt into the plastic (like the nut inserts on blue wheels).
And going back to your original question, M6 is a good size of fixing to use for edge-tapping, assuming your material isn't too thin. Obviously you can go for larger bolts if you want something stronger, but I certainly wouldn't go for anything less than M6 in featherweights.
I'm just using chunky wood screws to hold my HDPE. Can't see why that wouldn't be strong enough.
I'd hope it wouldn't get to the point of having batteries smashed up, but it's nice to know that there's a gentleman's agreement!
It's 20mm HDPE I'm using, may bolt other things to it if it turns out that it's well under weight which I seriously doubt, but I'd hope that say, 8mm screws would be alright since that gives about 6mm either side of it? I might help support the 2/3mm stainless base using some L-angles, just so that the linear actuator (if it fits) doesn't pull it off by mistake or anything! My only worry is my slightly unusual design on the back end, it's not final but it's this weird sort of half-hexagonal shape, designed purely to give spinners a little less to bite on but can revert back to square if needs be. Would like it to look a bit more interesting though if I can, got some plans for that but I'll see how things go...
The plastic's apparently due this Monday, not yet sure about the drive/scoop though - whenever it's all here, expect plenty of pictures!
Mini-Christmas time!
The Hardox scoop and drive system have now arrived, huge thanks to Mario for those! I'm rather amazed at how big the motors are - I knew Speed 900 motors and similar were a bit bigger than drill motors, but I didn't know they were THAT big! Must have spent a good 10 minutes just in awe of how huge they were - you can tell I'm new to this roboteering lark!
The Orange RX turned up the other day too, had minor problems with it to start with but kind of got it sorted, apart from the failsafing so that's still something that needs doing, but it seems straightforward as to what I have to do to get it working. Not touched that since Saturday!
Linear Actuators are also here, as mentioned in a previous post - I'm still playing around with the setups to see what I can fit in HardWired II under the weight limit for a micro extreme-budget 4-bar. I don't think I want a massive amount of lift on it, just enough to get underneath a machine.
Last but not least, I've got a great big sheet of 20mm HDPE to replace the aluminium shell, reason being that it was cheaper and easier for me to work with, and best of all I can reuse it on my other machines too. And I'll have a lot of spare for when the inevitable happens!
Pictures when I get back home - may even have HardWired II finished this week at this rate!
I lied, pictures tomorrow. Just got in, and I'm way too tired.
Just as a question for tomorrow's design session- wood screws in 20mm HDPE, any sizes I should look for? And how much does the screw need to go into the HDPE to give a firm hold? I'd assume a longer screw would be better, but I thought I'd ask before I go drilling any holes!
Also, I got a huge sheet of 2mm HDPE too to make an armada of antweights, because why not. Expect a few of those soon-ish after this one's done!
Here's the pictures of the parts from when they arrived the other day
https://pbs.twimg.com/media/BhVLZIQIQAAwfw2.jpg
Linear actuators just off to the side, there.
Basic layout of the machine here (pretend that the cardboard is >20mm HDPE)-
https://pbs.twimg.com/media/Bha1MmRIcAEFVg_.jpg
https://pbs.twimg.com/media/Bha1QrvIMAAZGCO.jpg
https://pbs.twimg.com/media/Bha1U1pIEAA4TCO.jpg
You may notice that there's a distinct lack of linear actuator in there, and that's because the wheels are only slightly larger than the height of the linacs themselves, and it'd be too much of a squeeze to get one in as well as having the lifting arm and all the other nice things that I'd need, so I've gone slightly boring and gotten rid for now. It's a real shame, but my engineering skills aren't really up to much so I'd rather go with something I know works than something that might fail.
Even worse, since I'm not entirely confident I could make the arm strong enough, there's the worry of me losing the ENTIRE front shovel if a spinner hits it right, which is just not a risk I can afford taking! Until then, it's super thick armour all the way, piling on the HDPE and so on. I am looking at drill-powered weaponry, even if it is just a gimmick because I am a bit conscious that some people think the 'push box' robots are boring. I've got some huge motors in there that are more than capable of putting on a good show, but I'll still look into it to see what I can do. Would like an arm on there, just in case I manage to get stuck on the arena wall...
Not really had too much time to work on it since the parts arrived, but before long I'll be sorting it all out!
Nice, I've got the same motor setup lying next to me waiting to go in a second feather one day. Though it came with different/smaller wheels.
But why do you need your machine to run both ways? If the linak does it's job it will turn you back over.
I can understand the benefits of being able to drive both ways and srimech at a more oppertune moment but beggers can't be choosers.
Thanks! And yeah, these are about 80mm I think, slightly larger than the old machine's but that's not necessarily a bad thing overall.
The reason it was to be invertible is more because the lifter was supposed to be like Storm II's, just as a compliment to the pushing power rather than a main weapon in its own right - the design would never have been able to self right properly, it would just lift robots off the ground so I could get under and push them about a bit. Not just that, but I'd need a secondary battery for it too, which is more weight and I'm not sure how close I'll be to the limit anyway with a heavy drive, heavy scoop and thick armour...
Not ruling it out just yet, but it might be something more for the second version of this machine. Was toying with the idea of a small spinner instead to rack up a few damage points in my favour but that's probably just going to stay an idea at this point.
Nice looking bits, I'm assuming the work of a certain Mario?
They are indeed! Very nicely done too. The drives are similar to other ones I've seen, just welded to an angled piece of steel
The only other pieces to the machine which aren't pictured here are the ESCs (TZ85As) Rx (Orange R620) and battery (5000mAh 30C, 4S) which are all fairly standard as far as parts go. They're all in HardWired I and I've not had chance to take them all out yet!
Still not properly started the build as I'm trying to find a decent baseplate. Call it a bit of a bodge if you want, but I'm going to attempt to cut down a 20mm HDPE baseplate to about 5mm and use that instead, or alternatively I'll get a piece of stainless steel or something to make it work. Issue at the minute is getting something strong enough to bolt/weld this drive system and other parts to, whilst also keeping it workable with basic tools (cordless drill, hacksaw, angle grinder) that's also cheap and readily available. I know that's a bit optimistic, but it's what I'm needing to do at this point!
Other than that, I'm now designing an ant and beetleweight made out of leftover HDPE from this, the beetle's going to be a wedge shaped drum spinner (already got some of the structural parts for that after a brief practice at cutting the 20mm HDPE) and the ant I'm not really sure of yet, but I've got a basic 4wd wedge chassis made from 2mm HDPE and bits of dishwasher. Basic idea of that one is that it's cheap to fix up, and would probably get very badly damaged pretty easily. Servo drive most likely and dishwasher-mystery-metal wheels with a rubber band on them for traction, and again would get pretty badly wrecked. Would most definitely look fantastic whilst getting wrecked though!
A 50cm*50cm 5mm thick sheet of HDPE is 8 quid from Directplastics. How would you cut the 20mm stuff down? I can't think of any half accurate way with hand tools. Potentially very material-inefficient, too, assuming it could be done at all; the cost of material lost in doing it is probably about the same as the cost of some 5mm sheet.
If you can get some stainless sheet, even 1mm thick will make for a sturdier base than 5mm HDPE. Of course, it is harder to work. If you have a hacksaw, patience, and suitable drill bits you're there. ;)
A source of thin steel in huge amounts often for free is kitchen white goods.
That's not too bad, thinking about it... And I'm not really that sure to be honest, it was just an idea. Was going to cut a chassis shape and cut it down slowly with a sander. Probably going to go for the steel route though I think! Having such a powerful drive, I'd hate for it to warp the plastic or whatever over time... I do have a friend who's got some scrap stainless, but I have no idea on the thickness, so I might check that! Probably buy some cobalt drill bits and see if that helps things!
I do have a couple of dishwasher sides spare, never used them because they seemed to bend a tad bit too easy... Might give them another go though!
Well for lols, NST was thrown in with a washing machine in '12 and it left it looking pretty sore, so if you can get and work thicker stainless, it'd be a good idea. If this baseplate is structural, as in, it holds the scoop to the drives, then you'll want to make it as chunky as possible. If the bulkheads take the load (generally a stronger construction method) then the base can be thin and serve to keep electronics in and dust out.
I've sourced some materials, going to measure those up when I can - hopefully got some stainless on the way too, so I've got a bit of choice! I think 2mm will be my absolute limit when it comes to thickness, though I think that might just about do it...
As for construction, the idea was that I'm going to have a box of 20mm HDPE that's all attached together, bolt the scoop to the front of that, then bolt the lot (probably the bottom of the scoop too) to a baseplate. Within that box I'm going to have some internal supports/separators that'll also be HDPE, and if I can't bolt the drive to the baseplate enough, I'll probably attach it to the HDPE. I've got a paint diagram somewhere that I'll probably upload in the morning...
Been out and got some screws too, mixture of M6 and M8, and between 40 and 100mm long, the m8 100mm ones are going to be for the main structure, M6 being for the baseplate and lid. Got some epoxy too to potentially glue the drives to the base or the HDPE. Might not be the best solution on its own, but any help I can get to make the things stay where they're supposed to can't be a bad thing!
If you rotate the wheels on your motors you'll notice that the bolts holding it in place do not turn along.
Or at least the ones I have that look exactly the same don't.
On my feather I used a longer bolt and a spacer to mount the motors directly to the sidearmour. With a couple of holes in that angle iron you could than attach your baseplate to that and the sidearmour making a rigid box with your motors supported front and rear.
Forget the combination glue/HDPE, that doesn't work at all.
Niels, take my word for it, replace that spacer with a rubber dampener/shockmount. To rigid ain't good for the gearbox.
I'll look into that, but he rear of the motors are mounted slightly loose.
Attachment 4366
Though a section of hdpe is covering the top of the motors as well, there is still some wiggle room to slide slightly in and out and allow the whole gearing to flex a little.