[marccenter]

[quote=windell747;839623] Problems:

2)when I floor the joystick forward, traction control works pretty well. Then if I let the joystick go and fly back to center, I get some jerking in the driven wheels. If i were to bring the joystick back slowly, the jerking doesn't occur.

What am I asking?:

2) Should I filter my slip ratio and motor commands somehow? If so should I use a lowpass filter or something similar? Or a rate limiter? I would like to remain simple and effective.
QUOTE]

Absolutely, removing those uncontrolled large transients will help solve a multiple of problems on motor commands. I typically filter the joystick command input (which filters the motor command as it propagates its way through the control algorithms). Even a rate limiter with a 25 percent change per loop or time event can make a big difference.

My vote is to go with a rate limiter. I think it is simpler to implement and more intutitive to understand when explaining to high school students. We use rate limiters in Matlab/Simulink at work all day long and I believe a standard Simulink block has been specifically created for that feature in the Control System Library.

BTW, Does Labview have such a block already created? If not, here is one recommendation for FIRST to add next year - a standard blockset of commonly used control functions (Table Lookups, Rate Limiter).