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SJSU Students Working on Spherical Drive System for Omnidirectional Vehicles

By Rain Noe - September 13, 2012

in Cars

This is the craziest design for a drive system I've ever seen. Let's say you had a small wheel, like the one in the photo above, that had a perimeter made up of smaller wheels that rotated in a perpendicular axis. I'm sure you don't know what the hell I'm talking about, so peep the quick vid below and pay close attention:

Now let's say you placed three of those "omniwheels" in a triangle formation, provided them all with motive power, and placed them in contact with a larger sphere. Then you can do nutty stuff like this (starting around 0:42):

To what end, you ask? A team of engineering students at San Jose State University are working on a spherical drive system (tagline: "Reinventing the wheel") in order to create an omnidirectional motorcycle.

"Despite having seen spherically driven vehicles in futuristic movies such as I, Robot, there has not been a huge push into the realm of the sphere," the team writes. "We believe that the versatility of the sphere drive can give us a whole new degree of freedom and safety that we have yet to discover."

The project's blog went dead back in May, as the school year wrapped up, but last week the team posted a detailed status update on Facebook. Hit the jump to see the technical challenges the team is currently trying to solve.Hey Everyone,

So there seems to be a lot of recurring questions, let me try to get them all (hopefully) in one go:

Spheres are made of Carbon Fiber/Fiberglass with a very tough industrial rubber coating, for traction and force distribution. Yes, we have discussed many other ways of making the spheres that would be 100 times better, but raising the funds for making a 2 foot sphere x2 is never easy...They are rigid enough and provide enough traction for this purpose. No the spheres won't go anywhere if the spheres lift off of the ground, they are contained.

The Spheres can wear somewhat unevenly in initial testing but as the motors are all evenly preloaded to the spheres to for maximizing traction.

We will have videos of the final bike as well as a live unveiling, once we have the prototype up and running (hoping for end of 2012). As far as test pilots...I call dibs! Jk, it will likely start off without a rider until we can be certain of predictable motion. Currently, it does roll as it sits but where's the fun in that?

Will this work and is it practical? There needs to be some fundamental additions/changes to the design to make this thing feasible; such as braking, traction, cost of manufacturing, and of course a bullet proof control system for high speeds.

Why would anyone want a spherical drive bike? Safety...Stability...New degrees of freedom are a start. I don't know about you, but to me spinning while flying down the street would be lots of fun.

There have been many comments about suspension, and there actually is 2 shocks in this dual swing arm design, so some dampening does exist. A pneumatic tire does an excellent job of cushioning the rider further but we'll leave it at that.

Cost? If you have to ask you can't afford it...only kidding, but seriously though...it's a lot, think Tesla Roadster status, but prototypes are never cheap. We hope to get this much lower if it is to be feasible.

Speed? For the scope of this project it is 5-10mph to get the controls right. Theoretical speed, purely going off of gear ratios between the motors and final drive, is something close to 60mph.

Operation of the vehicle will be intuitive to a motorcycle rider...somewhat...lean to move side to side, throttle and steering are there as well. All, computer controlled, to keep you from doing something that could end in a "bad time".

Be sure to check out older posts and our website at www.sphericaldrivesystem.com for more info.

Thank you all for the support!

via dvice

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b

12 years ago

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It took me a while to find it: http://www.miksovsky.com/chris/thesis/flowrider/flowrider.htm. Unfortunately, there are no dates listed, but I believe I discovered it in early 2000s.
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ian milne

12 years ago

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Umm this is already a thing. you are re-inventing a working product.
http://www.youtube.com/watch?v=tPmC4KPvOfg
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Lori H.

12 years ago

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A few years ago, Function did an in-house project creating a self-balancing omnidirectional robot you might want check out: http://www.function.com/?p=industry&c=orb

What we do for fun in our "spare" time here.

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Mike

12 years ago

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There's bound to be some interesting technology that would come out of making a project like this work. If anything, it's better than just a computer rendering. Projects like these don't yield just impractical motorcycles, but are more proof-of-concept exercises. For that, I applaud them.

While we're on the topic of omni-directional vehicles, take a look at these: http://en.wikipedia.org/wiki/Mecanum_wheel
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Bryan

12 years ago

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hmmm im curious as to why I would want something bigger than two of my motorcycle options combined.

Good luck with the project though I would like to see it in motion.

I see this thing in some sort of water setting not on the street.
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Adrian

12 years ago

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Function Engineering (disclosure: I worked for them around the time) made a self-balancing sphere robot using a triangle of omni-wheels in 2008-2009. Pictures, description and video are on their website:
http://function.com/

(Unfortunately, I can't find a direct link. It's under "More"->"Robotics")
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phaedrus

12 years ago

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I'm continually amazed at how far people manage to get down the path of prototyping before someone finally asks the really important question:

Why?

"Because nobody's done it yet" is not a good enough answer.

Why a motorcycle? If you're experimenting with spherical wheels, what does the motorcycle form factor get you? Wouldn't a tripod be a much more stable platform?

There are very good, solid justifications for the way bicycles and motorcycles are put together. They take advantage of the way the human body is formed quite well. Spheres? The inherent instability of putting two of them in a single plane is not a problem you're likely to solve by making a 'motorcycle' out of it. You're introducing far more problems than you solve here.

For what it's worth, to me this is Adam Savage's "I reject your reality and substitute my own" approach to engineering. It just makes no sense.

I admire their tenacity, but honestly there are bigger problems to solve than this.

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Ken J

12 years ago

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I'm wondering if at some point for maintenance, the user will be required to remove the wheel sphere and scrape off the junk that collects on the rollers...
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Tamas Nyilanszky

12 years ago

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this not really a new idea for the design world, it will never be as efficient as a simple wheel. get over it, it is like hubless wheels...
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Thomas

12 years ago

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Hmm seems like you wouldnt get much power transfer.Why not just straight up use the omni wheels that they are using to move the spheres??
http://youtu.be/IlmKcohyXG0 shows exactly this idea in an existing product.
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