These are muscles that are made out of a rubber band. In the middle of a band is a motor shaped like a yo-yo. With the proper electrical signal and power, it will wind itself up, rolling up the band inside the inner spool. With either ends of the rubber band attatched to something, the muscle will pull. Put two of them side by side and you have muscles pairs like those found on human limbs.

AFAIK most robotics are based on hydraulic movements, so I think this is new.
-- lawpoop, Jan 15 2005

Why not just use the motor? I dont see the benefits of a rubber band around it. The only reason I see is to mimic biomuscle. Currently there are materials that can perform much better such Shape Memory Polymer. Also when u let loose, how do you prevent the sundden burst of kinetic energy from the rubber. Biomuscles dont behave in such matter.
-- neoearth, Jan 15 2005


Well, it's a cheap and forgiving way to generate a linear force, and it saves you the trouble of adding a spring. With a clutch or the right gearing it could exert a constant force without using power. With a clutch on the joint it would effectively adjust the power or the motor. It might be useful for running.
-- tiromancer, Jan 15 2005


Does it have to be rubber? Couldn't any thread do the same job?
It's potentially a good idea, because perhaps the motor need not be at the immediate location (i.e. good for fingers).
-- Ling, Jan 15 2005


The rubber bands play a critical role in avoiding "baked" comments.
-- tiromancer, Jan 15 2005


[neoearth] I bet rubber is a hell of a lot cheaper than shape memony polymer.

With a device such as these, which can expand and contact, you can setup artificial muscles on a skeletal frame. You would have animal limbs.
-- lawpoop, Jan 15 2005


[tiromancer] Are you saying that this has been done with other materials, or that motors have been baked?
-- lawpoop, Jan 15 2005


I have twenty cassette motors and rubber band drives on the floor here. They have their uses in generating continuous variable speeds for a robotic light/sound producing orchestra. That's a lot of muscle work.
-- mensmaximus, Jan 15 2005


Hmmn. Many robot hands have used string or wire to drive the fingers, as [Ling] pointed out. I don't know of any which arrange the motor the way you've described.

So I guess I'm saying that motors have been baked.
-- tiromancer, Jan 15 2005


[tiro] Isn't what you're describing a motorized pulley system? Muscles aren't like pulleys. Maybe I didn't make this clear, but in my system, the motor is in the middle of the two bands, so the whole contraption acts like a muscle. Usually pullets are attached to something hard?

This motor 'floats', held only by the two bands or rubber or stretchy material. The ends of the stretchy material are attached to the frame or skeleton. So you could use this for emulating legs, whereas you can't really use pulleys for legs.
-- lawpoop, Jan 15 2005


I thought most current robotic systems were either servo or stepper rather than hydraulic.
-- bristolz, Jan 15 2005


ping!
-- gnomethang, Jan 15 2005


[bristolz] How do the 'arms' on garbage trucks or backhoes move around? Isn't that hydraulics? I'm not really sure, this is not my area of expertise/interest.
-- lawpoop, Jan 15 2005



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