Why this Omni-Wheel is Really Weird
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- čas přidán 30. 01. 2022
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Part 2 - will it balance on one wheel?: • Omni-Wheel Balancing R...
What about if we could actively drive the smaller passive wheels around the circumference of an omni-wheel? Then we could have a robot with one omni-wheel and make it balance in both axes.
I found a project called OmBURo, and I’ll a put a link to the video and details in the description. This robot does exactly what I’m looking for - it consists of one big omni-wheel with driven wheels around its circumference. This allows it to balance in both axes.
The Honda U3-X is a personal mobility solution, and it also features a two-axis actively driven omni-wheel. This is larger and looks pretty robust since it can carry a human.
Links:
• OmBURo: A Novel Unicyc...
arxiv.org/pdf/2001.07856.pdf
patents.google.com/patent/US8...
patents.google.com/patent/US8...
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Former toy designer, current CZcams maker and general robotics, electrical and mechanical engineer, I’m a fan of doing it yourself and innovation by trial and error. My channel is where I share some of my useful and not-so-useful inventions, designs and maker advice. Iron Man is my go-to cosplay, and 3D printing can solve most issues - broken bolts, missing parts, world hunger, you name it.
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Check out part 2 - will it balance on one wheel? czcams.com/video/B_bXW2vfkm0/video.html
I don't know if you know this, but herbie was ment to me in fan4stic, and was ment to be just like the robot at the start of this video, but with a soccer or basketball!
What university major is to chouse in order to make this kind of cool robots?
czcams.com/video/-jqBKZkPn80/video.html
This really grinds my gears.....need to angle the teeth properly for engagement. Deeper grooves. Gears need to engage properly to get any work out of them. I wish I lived in a higher IQ dimension.
I really couldn't figure out the potential advantages of a single complicated wheel over 4 simple wheels... What is this going to be applied to?
The Honda U3-X looks like a chair an evil mastermind would have
I want several of it and its further evolved descendants.
It looks like something a hilarious Bond villain caricature played by Mike Myers or David Mitchell would have.
Exactly what I was thinking
OK Go did an entire music video dancing with these. XD
We miss the option for the evil-sidekick-cat 😂
here as well as with some of your gearbox videos (harmonic drive, and I think one of the cycloidal drives), you use flexible filament for grip or ductility. It does do both of those things but it also saps efficiency and puts more load on the motor. Think biking on a flat, soft tire vs an inflated and much harder one. It's a balancing act to get grip and efficiency, but in my experience most 3d printing flexible filaments are too soft for transmission rollers. Maybe try PLA rollers with just a thin rubber tire on the small wheels for grip.
To be fair, compared to the traditional machining, hobby-level printers may be working with tolerances of 0.1 - 0.2mm even when tuned quite well, which is a lot more slop than you'd expect from machined parts. That could have an impact on how well harder rollers grip.
Have you ever used TPU depending on the infill u can't make it very hard
I don't think ur they are as soft as you think they are
@@syedsulaiman8380 I've got a roll of TPU and have seen lots of other people's prints as well. It may feel "firm" to the touch but its still very soft as compared to the rubber on a tire or drive belt.
@@EgorKaskader True, but even then I think you'd be better off with two hard rollers, with one having a thin TPU tire for more traction and to soak up the loose tolerances. Or at least one soft wheel and one hard wheel to minimize the energy lost to soft, squishy rollers.
Listen, you don’t know a thing
I think you may have mis-interpreted part of the patent.
Those "teeth" should be helical.
All you are doing is reducing the contact area between the driven and drive wheels in your design.
Either make them with matching helices, or make them smooth (smooth is probably better unless you understand gears and can machine them more accurately than a 3d print).
There's many things odd about this design.
you could get more grip between the sub wheels of the omniwheel and the rollers on the side plates by making the subwheels with a 45 degree diamond pattern instead of straight ridges. This way the ridges of the rollers will match up and apply a pushing/pulling force instead of mostly friction
@@getonthecrossanddontlookba5004 Stop spamming
@@justsomeguywithoutamustach7151 the original comment may be deleted, but based on the name I have a pretty good idea of what was posted
What you have here is essentially 2 mecanum wheels engaging intermediate rollers which engage the floor. In my opinion, 2 side-by-side mecanum wheels directly engaging the floor would be better. The only thing you would have to assure is division of the load between the 2 wheels. That can be done with a short equalization lever.
Yes but then there would be an extra torque when the two side-by-side mecanum wheels are rotating in the opposite direction
yes, but then the sideways movement would be very reliant on floor traction due to the mencanum wheels. his design would be more relaible on a vareity of surfaces.
An interesting observation, though for self-balancing (his ultimate goal with this) co-axial dual-mecanum wheels are notoriously difficult to use. They also have the down-side of blocking rotation about the axis perpendicular to the line formed between the two wheels, meaning that it wouldn't be able to balance on uneven surfaces (or go up a hill sideways) nearly as well.
here's a crazy idea,. have two mecanum wheels, but put one inside the other!
@@isaaczoesch158 ANY balancing scheme with 1 or 2 wheels MUST have friction with the surface just to balance. That's why bikers suddenly fall when encountering icy or wet slick roads. The 2 wheels could be guaranteed equal force-bearing by using a lever equalization link (like used in steam locomotives). The largest objection to the 2 side-by-side scheme is the torque about the vertical axis generated when driving the wheels in opposite directions. This could be mitigated by using 3 wheels side-by-side, the outer 2 driven together, & the center one separately. (He might object to this as the vehicle is no longer technically "1 wheel".
But the best way to do this is to have real legitimate gearing to drive the smaller wheels. This will be intricate with bevel gears, but doable with his extensive 3D printing equipment & experience if he makes the wheel larger. This would permit the small wheels to be football shaped, giving a true circular outside profile.
One seemingly important difference between your omni-wheel and its inspirations is that the smaller wheels aren't interconnected.
I think you are losing a bit of torque and efficiency potential by essentially driving only 1-2 smaller wheels at a time (the ones in contact with ground) rather than all of them.
After the ornithopter videos (no difference in AoA between up/downstroke) and that CMG project (no way to desaturate the gyros), it seems to be a bit of a common theme here that important details of the technology are routinely neglected. Amazing projects nonetheless, even if the results end up hampered by it
but they also seem to use a flexi shaft in both directions- I think they are only strong in one direction and you can damage them easily if you use in the other direction
Your 'prototypes' and 'test devices' are amazing accomplishments all on their own! Well done!
I don't like the patented idea - too much rubbing/friction. The OmBURo concept is much more realistic albeit with room for optimizations. Having the little wheels rolling obliquely against one-another sounds very inefficient.
...so does the flexible shaft and the 90° gears.
would to good to be true if this is every day life some day.
@@doopfdeckel
"would to good to be true if this is every day life some day"
Lol wut?
I think multiple 90° helical gear connections and a large circumference long flexible shaft would produce more friction/be harder to drive. Especially if you have a larger weight on top like a human
@@user-me3ce1fk4l or your mom...
hehe sorry i couldn't help myself
@@user-me3ce1fk4l they both use flex shafts in the original designs he showed.
Maybe those small driving wheels on sides can have some kind of spiral-shaped gear teeth so they would lock with the bigger wheels. Or it's named helix, not spiral. The point is that the teeth on the smallest wheels can be not just parallel to their axis but go under 45º angle around
Nice! 🙂
You should make the teeth of the TPU wheels disgonal so that they mesh like a gear. And you should perhaps make the large rollers more like a barrel, i.e. make the outer diameters somewhat smaller than the diameter in the middle.
Love it, love it, love it... sometime you just stumble upon videos that ust gets all the gears in your head turning.... this is def one of them!
Thank you so much for psting! Cheers from Dominican Republic.
What if you use interlocking conical gears on the ends of the rim wheel axles. So you get a form of 'bent gear coupler'.
These conical gears cab be made for other angles than just 90 degrees like in a differential.
Love it. Do you have any issues with the "strafe" speed being so much slower than the "roll" speed? Seems like it might cause a bit of a control problem
@C l a r a ♥️ Silence, thot bot. Men are talking about stuff that actually matters.
Probably just a case of using just some spare motors, he seems to have just been doing proof of concept here. A faster more powerful motor would do the trick, I think he’s still gotta work out the play in the rollers themselves to work out precision and accuracy with the movement before being able to balance I suspect
Brilliant concept, great execution as usual 👍
I bet if you used a narrow hub for the drive rollers with a thick you tread you will get the best of both worlds. Flex of the wheel and less play against the axle.
Freaking amazing build. I look forward to seeing more.
James, for a flexible shaft, you can use a spring, like what you find in a drain snake. They are super tough and can take a lot of torsional load while bent in a radius.
think we need to show more appreciation to Honda who are just inventive geniuses.
Honda's R&D dept christmas parties must be fuckin' wild.
if you had a singular ball in the center with the rollers acting as stabilizers instead of the locomotion; could you then have an omni-wheel made from a ball?
czcams.com/video/byUo4EagXu0/video.html that would be this with a smaller ball
Problem with a ball is the dirt you pick Up from the ground getting stuck in the drive, if this wasnt the case Every car in the world would have had globular Tires by now
@@johnpetters3328 Brushes and maybe compressed air
@@jennalove6755 Yeah, seems like it would be pretty simple to push air through from the top to flush out and even cool the wheel if need be.
That's so clever!
Excellent video. Hope to see more of this later.
Hello, thank you for your awesome videos. But I have one question on this particular video.
Wouldn't it work better if you had printed diagonal lines on the little hubrolls instead of the straight lines? So that they could line up better with the bigger outputwheels wheels.
You're seriously a genius man... I wish I had your level of consistent intellectual persistence
Idea: mount the two driving wheels at a slight angle relative to the vertical central plane - this way you only get traction - and, more importantly, friction - where you need it: at the bottom
It strikes me that the whole mechanism could be simpler if you were only concerned about driving the bottom 3 or 4 rollers.
Yes, the only reason to drive all the wheels is simplicity of design
Was about to comment on that as well! But slanted wheels would cause problems with contact patch between the main and driving wheels. The same goes for smaller and eccentrically mounted (towards the bottom) side wheels. Maybe some clever geometry could prevent this?
@@huzeff I'm sure the geometry would have to adapt - but that's not an issue for James
This is so cool, that guy just floating about on a chair in all directions is awesome I can't wait to see the next iteration...cheers.
Wow this is an awesome project. Very detailed and time consuming but an amazing project. Cannot imagine how long the prints took where I can only stand to print at max 4 hours at a time lol
I wonder if you could print a helical tooth pattern on the outer rollers that the smaller drive rollers can bite into? I assume it would have to be two counter-twisting helices, one for each side of rollers, so effectively the outer rollers would just be knobby.
This will probably not work because the outer wheels are flat/cylindrical and not round/parts of a torus as shown in the patent. But its worth a try, i guess 🤔
I was thinking this as well but having trouble thinking of a profile that would allow engagement with both sets of smaller rollers as well as the ground... Somehow your comment reminded me of a video I saw recently (past three months) with some very interesting knurled or cross-hatched gear profiles that might work.
So, if the two motors engage at the same direction but different speed, does it move diagonally?
Yes
Very creative.i really enjoyed the learning /development of the idea into the actual prototype. Would love to have a 3d printer .it just takes so much time.
I'm planning on using a number of these techniques on an upcoming project, to make a replica of the killer tire from the film Rubber. But all the parts have to basically float inside the walls of the tire so that the center remains completely empty. I haven't completely worked out if I want it to be able to lean left and right by shifting gyros or if I can turn the battery box into a servo actuated counterweight in the top and have that be sufficient.
I wonder if there is a special gear tooth geometry that would increase the contact between the red rollers.
*While I do like the experiments, I would also like to know what could be useful for?*
Because to be honest, sometimes I have no clue of any practical applications
In this case, I do know Omni-Wheel applications, but for 1 wheel? Not really.
2 omni wheels = omni directional bike
4 omni wheels = omni directional cars
etc
That's what I was wondering, the whole way through. I couldn't think of anything to do with it.
@@AnnoDominiAD But what's the point of an omni directional car or bike? And if it's so great, why choose the most complicated way to do it? What are we even talking about, here?
@@AnnoDominiAD its too complicadted to be durable and cheap enough
and on top of that you have grip problems due to small wheels
etc.
there are way simpler designs
Repent to Jesus Christ
“Search me, God, and know my heart; test me and know my anxious thoughts. See if there is any offensive way in me, and lead me in the way everlasting.”
Psalms 139:23-24 NIV
I just found this channel so I don't know anything about past projects but at 1:07 it's mentioned that it turns opposite way it leans.
Theirs a video called "Most people don't know how bikes work" by Veritasium
It mentions this weird effect is also on bikes. With a slow mo from the front. It could be useful to know these types of things as well as maybe getting slow mo of a unicycle turning.
Use pulleys on the secondary gears to drive the axles of small treads for better ground contact and power delivery, since you could make a high precision set of gears to drive the whole mechanism and keep it protected within the assembly. A tire or pair of tires might work well too…
This guy has more sponsors than the super bowl.
I'm always amazed seeing the solutions that the human brain can come up with.
I'm also impressed that people are capable of turning such ideas into actual 3D models so they can be manufactured.
I am a bit worried about wear and tear on this particular omni wheel.
Just wait until you see the solutions that non-human brains come up with....
@@Paul-rs4gd an air hockey table? 😉
One advantage with the Honda patent version is that all the small wheels are contributing to the rotation force applied the two or three wheels actually supporting the unit.
One possible way to make "rope" axle would be to use multiple layers of carbon fibre or kevlar with each layer twisted in opposite directions.
You would, of course, have to bind the rope axle . Could possibly use resin.
So darn cool. AWESOME PRACTICAL Designs and experimentation
Is there a way to have a motor fixed to the body that drives only the current bottom wheel? that way there is much less friction and you are not wasting power turning all those other wheels that are not touching the ground.
Edit: You would also be able to turn at the same time as you are going forward. It doesn't look to me like the current build does that.
Edit 2: Maybe the 3 current bottom wheels so you can turn when going up hill or on uneven terrain.
I thought the same thing. Why drive all the other rollers when the 3 on the bottom are doing all the work. You could just have a friction drive on the bottom 3 rollers.
You always have great socks, James. Completely off-topic, but I just had to point it out.
It never ceases to amaze me how many sponsors you can get in a video .
Fabulous work, congratulations. I have a feeling I'm looking at a summary of years of work. It's a wonderful new world we live in with 3D printers, cheap electronics and control systems.
If the center wheel and the two outer wheels had different centers of rotation then you could adjust it such that only the bottom would be "active" ... thus reducing friction. Great job at conceptualizing this.
Amazing how old the gyroscope is and never let us down and used so proficiently today in many different fields
The terrifying speed of digrodation. Two hundred years ago
, two-wheeled cars were made, railway cars on one rail. Not on the rail that occupies 2.3 of the width of the train itself, but a simple rail. And all this on a gyroscope. But then everyone forgot about it, and the technology went into stabilizers for ship guns.
I have seen a RC toy called Air Hogs Upriser that has driven omniwheel and able to self balance on single wheel. Its internal mechanism is more similar to traditional differential drive gears. Not sure whether it is still suitable for more heavy-duty robots.
That "tilting changing the way the wheel steers" is exactly why I decided to dismantle my one wheeled Vespa. I saw the 1000w one that Bel Y Bel made a couple years ago, and decided to try making one with a much stronger 3000w motor, and it was just too hard to control at that speed. You could definitely upscale this Omni wheel to a serious vehicle! I think would only cost about 2000£. Just mount a 42v 1000-2000w brushless ebike motor on each side.
Bro your work is amazing… oh god. Great equipment and program. thanks to share.
I think using worm gear can directly change the spinning direction from the large wheel to the small wheel. Moreover, springs or some elastic plastic can detach the gear of small wheel from the large wheel. When the small wheel press against the ground, the gear bind together again. This may reduce the energy loss due to the friction when moving the useless small wheel
I've gotta show this to my FTC team! They're gonna love this, thanks for the amazing video
I was watching and thinking "what about a reaction wheel" and then you got to that. These are very clever and cool machines you built!
The complexity is just crazy. To me it feels like a lot of excess mass and bulk when only the tiny wheels at the bottom are actually utilized at any given time.
If I were trying to make a single wheel balancing robot, I'd go with a tilted wok shaped wheel. One motor drives the slightly bent axle, while the other motor drives the wheel. The key is to have a small amount of bend, so it's possible to quickly switch direction.
It's possible for it to be passively stable, actually, but with a small hemisphere or ball shape it would require active stability.
You seem to know what you're talking about. What is the point of all this? What is the advantage of balancing a robot on a single wheel? Isn't four simple wheels far more cost effective and practical than some Rube Goldberg single wheel contraption? I just don't get the point.
@@hxhdfjifzirstc894 It's just fun to try and engineer. There isn't really a practical point.
I think a big solution would be to connect all the shafts of each big grippy gear on the center hub, together with a flexible shaft like in the other design. This way, when two gears do not interface properly, this effect is mitigated by all the other gears that do make full contact. This of course also asks for bearings next to each gear in the central hub, so this might become a heavy wheel by itself. But I think it's worth upscaling it a bit and going all the way.
Very cool! I wonder if there would be any benefits from making the drive hubs smaller, and offsetting them so the little gears only engage with the larger ones that are in contact with the floor. Maybe the little hubs could also be more perpendicular to the main hub (more parallel with the floor) so they could squeeze the driving gears harder, while also reducing the lateral twisting on the little hubs.
I seen a video on youtube bout a bolt with two way threads.. That is to say threads, which would allow you to turn a nut clockwise or counter clockwise and still tighten it or loosen it. instead of looking more like a screw. if you used this same idea on you main drive wheels, you coold put bi-directional "teeth/threads" into the main wheels that would fit the rollers on each side better and maximize contact and grip between the rollers and the main hub.
For in-line two wheel vehicles you actually do have to turn left before you can turn right. This is so counter intuitive most people will fail to grasp it until presented with a physical experiment.
For an omniwheel bike this would require you to slip to the left before executing the right turn. You would then have to reverse the procedure to come out of the turn. The required angle of slip can be calculated by balancing the centripetal force for a given radius of turn with the downward force of gravity such that the resulting vector is through the centre of mass to the wheels.
Very well presented, good work!!
Great stuff and description 👍
Dude, seriously. How come you are not working for space X, tesla, boston dynamics or related. This is the kind of smart people who has to drive our future!! Good work man!!
Pretty amazing work James. Inspiring.
AMIGO , ERES EL MEJOR, TU CANAL ES UNICO,SALUDOS DESDE CALI,COLOMBIA....GRACIAS!!!
I invented something similar back in the 90s.
It's purpose was to create a robot for robot wars that addressed the number one problem, the control and feedback system.
I called it Drive By Wire and you can see something similar in your one wheel robot and stabilised gun mounts in Main Battle Tanks.
Yours looks better though, can I use it?
I like the idea, probably you could make it lighter by only keeping traction in the lowest part of the wheel, as the rest of the wheel doesn't really work
Question: To get an angled path of travel(forward/backward and left/right simultaneously) would you rotate the two drive gears in opposite directions at differing rates? As in, the difference between the speed of the two rotating gears would be translated into forward/backward motion?
Ideally you wouldnt need any rotating small wheel apart from the one that touches the ground. So I am thinking either dont drive any wheel but the bottom one at a time or maybe a fixed small wheel that always stays on the contact area and comes into effect by a levering mechanism or similar when there is sideways motion needed?
I suspect it would be a good idea to redesign this so that the contact patch is not the same surface as the drive gearing.
Could you use small outrunner motors as hub motors for each roller or use 2-4 of them connected to each other via segments of flexible drive cable?
A very clear explanation of a very ingenious mechanism !
This is very interesting and I’m glad that you made it, but couldn’t you accomplish all of this just with two wheels each with its own motor? Kind of like how a tank works? Such that if both wheels are going the same direction you move forward, but if you control the speed of the two side-by-side wheels it could turn or have a semi directional thrust?
I’m sure there are some problems with this as well, but it seems like a simpler thing to work out and probably more efficient at getting power to motion.
What if you made the perimeter wheels spur gears (probably best with truncated teeth) and engaged them with a large wheel, basically a very thin slice of a large diameter worm wheel. Driving the whole assembly would move back and forth, and driving the worm gear backwards or forwards would rotate the rollers, moving side to side. Obviously not great for a dirty environment, but could be an interesting concept to play with.
Really nice. I wonder if you could get away with having 3 or 5 fixed small wheels at the bottom only, since you only need the big wheels that are making contact with the floor to spin.
That unexpected twisting was covered in that veritasium video with the bike that can (not/only) steer right.
The fact that the lines don't match up would mean they are actively reducing friction in that configuration - try using a surface of many consistently spaced bumps.
glad you took the advice and did it!
Three suggestions.
1) Run the side driver wheel plates on lower centers so only the driven wheels that are in contact with the ground are controlled. This should considerably reduce friction.
2) Barel the outer driven wheels to conform to the other diameter for a smooth ride and concave the driver wheels to mesh.
3) The" teeth" on the driver and driven wheels should be helical.
if you want a flexible inealastic material torsion transfer material, try speedo cable, or the larger flexible drive cables used to power tools
Could you make the small wheels bevel gears, and the larger wheels cross-threading bevel gears (similar to a bolt that can take both left and right hand threaded nuts) to reduce slippage? The math would be a pain though
I'm pretty sure the friction, if used day in and day out would rake havoc on the gears.
I enjoy they concept development of the project
Cool build man. I do think that the helical gear pattern will work much better. Check out the design of Torsen differential gear systems.
Hydraulic tubing makes a good flexible shaft that is cost effective. I've successfully used it as a 2 foot diameter flex shaft. I assume smaller diameter tubing would work in this case.
Really nice concept.wish to see how BMW AVTR wheels works..james should make one....
This is really cool but it seems to me it would easily break if you used it daily. IF there was a Hole through the middle of the Tire, Maybe you could cover the sideway rollers with a flexibel donut shaped outer layer, this way protecting it from damage and weather. Means you need to put the drive torus in the center of the wheel and find a way to transfer movement without to much friction on the protective layer so the idea isn't without cons im afraid. You are doing brilliant work, Keep it Up!😀
intersect subtractive cuts on the center where the rollers touch. Then you would perfect gearing between the angled rollers and the center rollers, but maintain tread on the center. As if you had a crosshatch pattern so that 2 separate angles of gear teeth coexist.
Great video! And where did you get that Bender head??!
For this current demo, would a design like a screw that goes both ways work for your central wheel? It would be less binding and always have a point 'flat' against the gear as it pushed on it I'd think. Would be less binding and allow you to tighten up the design a bit ya?
You could probably 'save' some torque if you have the non-contacting wheels disengage from the rollers, allowing for the torque to be placed only the wheels which have contact with a surface. Might be over-engineering it though, as I imagine it wouldn't make a huge difference but it's still a neat idea.
I think you could probably do something like this:
. If the roller hubs where slightly smaller they wouldn't be able to engage any of the wheels without pressure.
. as for how the pressure would be translated, without having to change the lateral wheels; you could design the main hub to allow for small vertical movement of the lateral wheels, so when pressure is applied--either from gravity or weight on contact--the wheels can engage with the roller hubs.
. finally you could add fairly low pressure springs to the bars of the lateral wheels within the new cut outs in the main hub, or where ever the vertical movement of the wheels is inserted, allowing for the wheels to 'reset' their position when contact ends - also stopping gravity from engaging the top wheels.
Alternatively if you want the lateral wheels to *only* work when contacting the floor--instead of whenever it contacts with *anything*--you could just apply a very small tilt to the roller base so only the bottom few rollers will ever engage.
This would be a really awesome robot if paired with reaction wheels to get it balanced and standing upright.
Great work, keep it up 😉👍
There's a simpler way to do that. You have a large wheel that's open on the inside as to house a L-R driving mechanism. The hub would be biased to the opposite side (like a car wheel) or use a hub less wheel with the rollers around it. The bottom where ground contact is made sits just 1 or 2 omni wheels that drives only the ground contact rollers left or right.
*The reason it's an omni wheel is so the forward/reverse rotation of the large wheel doesn't cause friction for the smaller wheel which drives the left/right motion.
*You may want 2 so that thetrnsition between rollers is seamless.
Can you print the small drive wheels with a worm gear like profile interlocking the outside wheels?
And maybe make the outside wheels a bit curved, ball like, and the small drive wheels concave worm gears? (Or would that hinder if the drive wheels hop over to the next outer wheel?)
I'm just a simple guy, I discover a channel that blows my mind in the first 10 seconds of the first video and I like and subscribe immediately
1:12 "steer in the opposite way it was leaning" - to start a turn on a bicycle, you need to give a brief push to the other handlebar.
I think that you should put bevel gears at the ends of the rollers to show turn one, turn all. And then put the motor and gearing inside one roller.
Seems like all of these concepts have a lot of mechanical complexity and friction that could be overcome by adding motors inside the wheel and use a rotary electrical brush system.
Linking the circumferential wheels though is still an interesting challenge. I imagine backlash would be a real issue. But perhaps tight bevel gears - perhaps in a high durometer flexible filiment, would do the trick.
Tbh it’s channels like yours that keep my inspiration going to get a degree in mechanical engineering
this is absolutely fascinating
if I wanted to study the fields required to create such an invention, which would those be?
would just mechanical engineering and programming suffice? or am i missing out?
I believe you may experience some better connection between the out wheels and the driven hub if the small wheels were a spiral threaded design instead of the level tooth-geared design. This would mean the threads on the bearing wheels would fit perfectly inside of the teeth of the drive wheels
That was really good, I can already see R2-D2.
Talking about Star Wars, I'd really like to see a functional BD droid.
Just a thought that may not work .....
almond shaped outside wheels to match circumference........with a double thread (15deg instead of 45?) and then the two drive disks can have a much better positive engagement and weight carrying on a full circumference of gear
I cannot believe I live in a time where this kind of bizarrely niche and amazing information is freely available to anyone..... There is hope for humanity.
Could you reprint the smaller rollers with a diagonal tread pattern that would then mesh with the lines on the big roller? Kinda like a tiny gear?