Torque on Parallax Servos

BipedPete

I am wondering if i could make a biped from unmodified parallax servos. A 2 to 4 foot tall complete biped. Could Parallax servos handle all that weight, especially the legs?

Mike Green

BipedPete,
That's like asking if someone could carry enough water for a family to use. You'd start asking "for what?" "how often?" "how far?" "how big a family?" "in a bucket?" "how strong a someone?" "in a tanker truck?" ...

Sketch out a design. Figure out where the forces would have to be applied. Would the servos be expected to "be" the joints themselves or simply provide the turning force? What kind of materials are you talking about? How heavy would this be?

I can imagine one biped design where these servos might work fine and another design where they'd be terribly underpowered. There's also a big difference between a 2 ft. design and a 4 ft. design.

BipedPete

Thanks for that answer.

bulkhead

Standard servos have usually around 50 oz*in of torque. This means it could lift a 50 oz weight with a 1 inch am, or a 1 oz weight with a 50 inch arm, or anything in between. You can also consider using springs and other mechanical devices to assist in moving a load/conserving energy during motion.

BipedPete

Thanks for that Bulkhead

Dave Hein

Check out the Futaba servo page. They have some servos that are specifically intended for robotic use. One of the robotic servos has a torque of 192 oz-in (1 foot-pound). They also have a "Heavy-Duty High-Torque" servo with a torque of 340 oz-in (1.77 foot-pounds) at 6 volts.

Dave

BipedPete

The point is to make the robot from parallax servos to see if it can be done.

Franklin

Then I'd go for it and modify your design so the servos are not used outside their specs. (use gears or levers to accomplish the movements)

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- Stephen

Bruce Bates

Pete -

If you do get involved with gears or levers on servos, there is an excellent selection here of all sorts of auxilliary equipment at Servo City:
http://www.servocity.com/

Regards,

Bruce Bates

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walice_drel

The paralax servos are to underpowered it would have to be less than 10 servos because any more weight and the legs wont work. Also 2-4 foot tall should be more like 18 inches tall for balance and less weight.

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