Thread: Three joint arm
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Unread 13-05-2012, 21:49
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@JohnVNeun
AKA: John Vielkind-Neun
FRC #0148 (Robowranglers)
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Re: Three joint arm

My Arm Design Methodology:
1. What orientation is the scoring object in when I pick it up?
2. What orientation is the optimum orientation of the object for scoring?
3. What elevation changes do I need to make to the object?
4. What is the simplest mechanism I can use to accomplish the above orientation and elevation changes?

Now, #4 is a bit tricky since "simplest" is somewhat subjective. How do I define "simplest"? My personal concept:
  • The less degrees of freedom the better.
  • The less actuators required, the better. (I give bonus points for pneumatics over DC motors, since they are simpler control wise).
  • Easy to control -- I want to be able to drive it with default code. I want my drivers to be able to maneuver it almost intuitively.
  • Low power -- I don't want to need to use a lot of motor power to actuate it. I like any arm I can use passive assistance on (i.e. surgical tubing) to do the majority of the work.

IMHO, multiple jointed arms rarely result from this methodology...

-John