Mobius Strip Tank

a mobus strip or Loop is a one-sided object known as a non-orientable surface meaning that within it one cannot consistently distinguish clockwise from counterclockwise turns you can read more about this on Wikipedia but we can easily demonstrate the principle by getting a strip of paper putting one twisting it and joining the ends together this means that we essentially have one continuous side so if we follow it all around we travel over what would have been both sides of the strip when it was flat and return to where we started also if we cut a mobia strip in half by just cutting all the way down the middle of it all the way around we end up with one massive loop with two twists in it which is quite interesting so I got a YouTube comment on one of my other funny tank videos from one of my YouTube channel members saying why don't we make a tank with mobia strip Treads with a twis in like that and they didn't really know why that was a good idea other than it looks cool and I don't know either so we're going to build one anyway and see what happens so I've designed some track links and they have these Square kind of pivot sections in the front here and that allows two of those tracks to Pivot against each other as well as bending normally to go around sprockets and that gives us around 18° of movement either way so it's time to 3D print a few of those up and see if this actually works in real life and what sort of rotation we can get out of this we're going to need quite a few links for the tracks so I'm using some 3 mm stainless steel in there and that fits nicely in the slot and we get that rotation at the link point so with a couple of those together we can see that it bends in both directions so it pivots like this and also bends to go around the sprockets which is just what we need for a tank so there's 10 track links together and as you can see that almost twists all the way around with 18 Dees on each one we should get the complete 180 but we're not quite there probably need another one to get round to 180 that's probably because of the tolerancing on the 3D prints on those swiveling parts obviously it bends the other way so it can go around the sprockets I'm not sure how easily it's going to run when we twist it and we want to get it back on the sprockets at the end to come back to the bottom again but there we go let's put some more together and see what happens we don't do these things cuz they're easy though we do them cuz we thought they'd be easy so there's 11 links together which pretty much gives us 180° quite comfortably obviously this tank is going to be quite long though just so we can get that twist in the length of it so the rest of this looks pretty much like a normal tank the only difference is we've got this massive Gap in the top here so we've got space to get the twist in the track in this is going to turn out to be quite a sizable assembly so just a quick ad from my 3D printing sponsor thanks to LOL spot for supporting my channel with 3D printers makes it much easier when you've got lots of printers to make all the parts in parallel this is part of the drivetrain which is basically a cylinder which fits between two sprockets and those go at each end to drive the two holes in the tracks there's a lot of those needed though because we need four sprockets per track and two tracks and each sprockets got two ends the whole thing's pretty long so I'm using the L bot Taz long bed which has a bed twice as long as the other printers to do the main side pieces for the track thanks to 3D fuel for the filament for this project you can now get 10% off at 3D fuel.com with my special code and Link and I'll get a small commission I printed those side Parts with a 1.2 mm nozzle as well so actually really big tough parts and they didn't take too long to print obviously there's one of those that goes on each side of each track so there actually four in total that fit like that here are the sprockets themselves so there's two ends you'll notice one has a longer piece on that's to put a pulley on one of them to drive them and those of course go either side of the cylinder there and they just screw down thanks to Simply bearings for the bearings for this project the last time I did a tank I didn't put any bearings in it was just metal on plastic and it didn't run very well so check out Simply bearings. co.uk of course these sprockets run really well now I'm just running them on studing but that studing allows me to screw the whole tank together with nuts I remember to put bogey wheels on this tank so these fit in the middle there are three of them which fit in the middle of the track at the bottom you'll notice those are quite skin and we'll find out why that is later and those are fixed with just some nuts done up against each other either side so they stay in place and that holds the whole frame together I did remember to put the belt on and the pulley so we can drive one of the sprockets later the next parts are these which Hold the top sprockets and these screw onto the frame separately and we'll find out why that is very shortly also got these pieces which screw between the two sides and that just makes the whole frame a bit more rigid so it doesn't twist and it's just not relying on that studing to kind of hold the whole thing rigid the top sprockets fit between these gray plates and I made those separately and that allows me to be able to reprint them really easily to tension the track up by moving the top sprockets apart without having to go and reprint the whole side with that massive printer so that just makes things a bit easier for getting things tensioned so that's one side done we've got to put the track on now and see if we can get that twist in I've put this track together with 30 links in and I think we need another eight or maybe 10 in there to try and get that twist in of course which will make that section a bit longer so let's let's put together the rest and see if this actually runs fine with the twis in and if this works at all with the assembly the length is the minimum amount of track links I could get in there to get that twist in and have the track go all the way around is 37 links so there it is it actually seems to run surprisingly well with that twisting I was expecting it to be far worse however if I run it too fast or I run it too far then some odd things happen so that track isn't quite as tight as it should be and that results in the sprockets at the bottom there popping completely out of the holes in each track link that they're supposed to drive and sort of getting stuck in between the tracks so yeah that track is quite loose and I couldn't really make it tighter I do have these gray plates that I can just reprint though so I've moved the holes around 10 mm to the left on one end and that's made that track quite a lot tighter I've used these motors quite a few times before for crawling Vehicles they are 24volt worm driven gear boxes and they're pretty powerful I've made a hub for each of those each one has an M6 nut and a grub screw in there and then there's a pulley piece which fits on separately so I can reprint that if I need to ret tolerance it as well that fits onto a plate which also allows me to rolance the tension by just reprinting the plate so there it is fitted in there and of course that's driving that pulley and sprocket I fitted earlier so here it is running under power I've just put a battery on the motor there running it backwards and forwards this has actually worked out pretty well I'm surprised that twist works as well without the chain coming off and also the sprockets now stay into the track Ling so I'm pretty happy with that so we just need to build another one so you might have noticed these two bits of studing poking out the other side obviously that's for the other track that we're going to build out there but before we put the rest of that together and see how well it works it's time for a quick answer on the video sponsor which is PCB way PCB way is a One-Stop shop for PCB manufacturing assembly and other types of manufacturing services including contract manufacturing and it's all Under One Roof PCB way manufactures all sorts of boards including Standard fiberglass boards but also aluminium pcbs flexible pcbs and rigid Flex pcbs which are part rigid and part flexible PCB way also provides CNC services including online CNC Machining sheet metal fabrication 3D printing and injection molding the CNC Machining Services include a wide range of materials including aluminum stainless steel and various Plastics if you don't see the material you like you can also choose from Custom materials PCB Way's 3D printing services include SLS SLA DLP fdm and More in iety of materials check out the PCB way website to browse through a variety of finishes and get a quote check out the PCB way Shar project section this is a community of User submitted projects with PCB schematics and parts listing so you can reproduce the projects you see there they also have a module store which has all sorts of items for sale such as Arduino boards toolkits robot parts and kits and sensor modules find out more now at pcb.com and I'll put that link in the description to this video right let's put this together and and see what happens the other side's pretty much exactly the same so in the middle we now have some Electronics made of an Arduino Mega and an orange RC radio receiver and I've got two 6s lipos wide in series driving the motors through two bts7960 motor drivers and I think those are rated at something like 28 volts and 40 amps which is more than enough for those Motors as usual I'm using my DSM remote which is a universal remote for all my projects and you can check that out in my channel on the whole it runs pretty well I'm pretty happy how this has worked out it's pretty much as good as any RC tank I think so yeah let's just drive that up and down a bit seems to work fine the twist in the track also has stayed on and it just seems to just Cascade properly off and on the sprockets at the end so I'm really happy with that too but let's see what we can do with it can we drive over obstacles and all sorts of things that tank should do well a bit of aluminium extrusions no problem for it but let's try a bit of a ramp so yeah that seems to work okay even though my tracks have no grips and they're entirely smooth let's try an even bigger ramp made of some smooth shiny acrylic and that seems to work just fine too what about an even bigger smoother ramp let's see if we can get up there well no joy to start with because those Treads won't go over the ledge which is probably about an inch and a half deep I'm just going to help it and just get those front Treads up to start with uh it's okay while we're pushing against the ground but as soon as we leave the ground then that table's just too smooth and we've got no grips on our track so that's no good at all well that seems to work just as well as any other 3D printed tank I guess but the question you want the answer to Is Why have we got this mobia strip track why have we got this twist in the track so the thing I could come up with was that when we look at really big track vehicles like Megabots for instance they've got loads and loads of friction with the ground they have real problems turning because when one track goes forward and the other one goes backwards some of that track at the ends basically has to slide sideways so they have loads of problems with friction and they get stuck so what they did was put smooth nylon plates all over the Treads to reduce that friction and make the track smooth now in my case the tracks are smooth anyway so it's fine at turning and things but it's also really bad at gripping ramps as we've already seen but in this case we've got this twist so we can have one side of the track with treads on that's something that grips and the other side smooth and then we get the best of both worlds um although we've only actually got one side cuz it's a mobia strip so I'm not quite sure how that's going to work out so I cut up some big sticky pads into lots of small pieces and put them all over the tracks making sure I avoid the holes where those sprockets go of course and also the bit in the Middle where the dolly wheels go and I've covered the whole track and basically we've covered one length of the track so that means that we get one entire circumference of the track which is completely smooth and then eventually we get one whole circumference essentially the other side where we've got grips on and so we have one transition point where it swaps over that's actually only in one place on the track so there's all of the grips and then you can see the transition Point coming round then we get one complete circumference of a completely smooth track again and another complete circumference with the grips on which gives us quite a lot of variety so you can see the bogey Wheels run in the middle of those pads there at the bottom which is why they're skinny and why I put the pads there and also those pads run in between the two halves of the sprocket and that's why that cylinder is so much smaller than the two half of the sprockets which are screwed onto the end I also moved the holes in the gray Parts again to tension those tracks up so they're much much tighter so nothing weird happens now this grips let's try driving again though and obviously backwards and forwards works perfectly well no matter what the orientation of the tracks and those grips is but as soon as they get out of syn and we try and turn with the tracks turning in opposite directions then basically of course the smooth side just slips and the grippy side overwhelms it and so lots of weird things happen when we try to steer depending on what the orientation of those two tracks is and the position of the slippy part and the grippy part so there the tracks are turning in opposite directions but the one with the grips is winning we can't turn at all here they are in sync with two smooth sides facing the ground and of course that just turns fine now and we don't have too much friction either so we don't get that screeching sound from the rubber grips wiping on the floor so that would be quite good if it was a massive robot with loads of Mass on but of course as soon as we get one grippy track that just totally overwhelms the other one and it'll only go in a straight line but let's try the ramp again so obviously the smooth tracks won't get us over the edge there on the tabletop as soon as the grips come round then that drives up there perfectly fine and because we've got that whole circumference of grips we've still got plenty more to go and we've reached the end of the ramp so that plan worked out quite well I'm not going to drive off the end though so let's just drive back down again and now we've got two smooth surfaces on the ground we can turn around perfectly well it will of course drive on other surfaces perfectly well just like a normal RC tank so if there's a bit of grip on the ground like the grass then basically things work perfectly well it doesn't really matter what the orientation of the grips and smooth is and I can still turn perfectly well on the grass there because we just seem to get equal friction driving over uneven surfaces like piles of wood works pretty well as well not really seeing any slip when we've got the smooth parts of the tracks got one smooth and one grippy there coming around seems to work just perfectly well the grips do help of course but basically it doesn't seem to really matter and it will drive over any older loads of wood or any other obstacles perfectly well just like a normal RC tank I'm going to publish all the cad and code for this as open source and you can find the link in the description to this video and don't forget you can support me through patreon if you'd like to and if you like funny tank projects and check out my channel I've got a tank that bends to steer a wave Drive tank and also a triangular-shaped omnidirectional tank that can move in any direction and you'll find all of those in my channel

Channel: James Bruton

Views: 516,118

Keywords: mobius strip, mobius strip tank, infinite loop, infinite track links, 3d printed mechanical infinite loop, 3d printed mobius strip, 3d printed tank, 3d printed machine, practical use for mobius strip, infinite belt

Id: AoWeljpA6-U

Length: 13min 55sec (835 seconds)

Published: Tue Nov 14 2023