Quote:
Originally Posted by wesleyac
Just want to point out that this is probably easier than you think to control - you can do feed forward by applying voltage proportional to the cosine of the angle of the arm to cancel out gravity, at which point it becomes a (approximately) linear system, that is fairly easy to control (Although there are still some considerations to be taken with the difference between going up and down). A FF + PID arm is much easier to control than one with surgical tubing or a gas shock, imo.
The point that programming can only do so much is definitely valid, I just wanted to point out that arms aren't too difficult, as that's what we spent our season doing  |
A few questions (just started taking physics this year, apologizes if any of these questions have obvious answers that I haven't learned yet).
1. How did you determine the multiplier required to allow the arm to cancel out gravity?
2. How does multiplying by the cosine of the angle of the arm result in a linear system? Isn't cosine non-linear by definition?
3. Why do you not simple scale your voltage multiplier in proportion to the angle of the arm?
Thanks for all your help!