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Unread 25-01-2015, 12:58
gpetilli gpetilli is offline
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Re: Constant Rate of Acceleration

Many teams will impose a ramp on the joystick command input to limit the change in velocity (a.k.a acceleration) command. Some of the speed controllers can also do this for an individual wheel (which will mess up the mecanum kinematics). Yet another way is to use the accelerometer built into the roboRIO and reduce the command value if the acceleration is getting too close to the "spin out" speed. The accelerometer is probably better suited to detecting that you already spun out and therefor maybe the least useful option.

I would recommend imposing a software ramp on the joystick command even if you implement some other control method. It also helps to limit peak motor current - especially if the driver is going full velocity forward and throw the robot into full reverse - which will often pop a breaker.