MAXMotion Velocity Control

MAXMotion Velocity Control utilizes the MAXMotion parameters to improve upon velocity control. Honoring the maximum acceleration, MAXMotion Velocity Control will speed up your flywheel or rotary mechanism in a controlled way, reducing power draw and increasing consistency.

MAXMotion Velocity Control utilizes an internal velocity closed-loop controller, so transitioning from Velocity Control mode to MAXMotion Velocity Control is as simple as setting a maximum acceleration and changing the setReference call.

It is called as seen below:

Java

m_controller.setReference(setPoint, ControlType.kMAXMotionVelocityControl);

API Docs: setReference

C++

using namespace rev::spark;

m_controller.SetReference(setPoint, SparkBase::ControlType::kMAXMotionVelocityControl);

API Reference: SetReference

MAXMotion Velocity Control will turn your motor continuously. Be sure your mechanism does not have any hard limits for rotation.

Tips for Smooth Motions

• If your motion seems jittery, try reducing your PID constants, especially P. If the underlying velocity PID outruns the acceleration target, the motion may seem jittery and the velocity will not increase smoothly.

• Make sure your units are correct: maximum velocity is set in RPM by default and maximum acceleration is set in RPM per second by default.

• At low speeds, the acceleration may seem wobbly or inconsistent if the loop has been tuned for higher speeds or vice versa. If both are needed, try tuning separate PIDs and switching between slots when needed. This may be easier than finding those perfect constants that work beautifully across the board.

Migrating from Smart Velocity

All Smart Velocity constants and PIDs can be transferred to MAXMotion Velocity Mode. Be sure to transcribe any Smart Motion parameters to the MAXMotion parameters.