On Fri, 7 Jan 2011 11:25:51 -0800 (PST), "
wrote:

On Jan 6, 9:04*am, Bill Noble wrote:
On 1/4/2011 8:35 AM, Steve Lusardi wrote:



You don't want to use a stepper motor. You lose far too much torque and
waste far too much energy stopping and holding. Think PM motors with
pulse width modulation to vary torque and speed. You must use feedback
with a position encoder (absolute) and a tachometer. Depending on the
gear set used, you may also wish to use an armature shaft brake.
Steve

wrote in message
...
Hello everyone, i need help at this:

I want to make a joint like in the human arm and make it work in
certain behavior.
so, i know i need a stepper motor controlled by microchip like
PIC16F1825 and attached to the mechanical joint.
but what i need to know:
1- what kind of motor to use (how much KG can raise, the
price, ...etc )
2- what kind of joint
3- how should they attached to each other

Thanks a lot to every one helped me...

you need to determine how fast you want it to move - how much weight to
lift, holding reqmts, etc - hydraulics are frequently used, but if
motion doesn't have to be too snapy a piezo motor provides high holding
torque and is light/small

Thank you for your time.
i want the motion to be smooth, and the motor must endure weight 1 KG
as a maximum.
the main problem is in the connection between the motor and the
joint.


http://www.rocomcorp.com/

One of my clients. Helical coupler manufacturer

Gunner

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