 Setpoint weighting is a simple form of feed forward.For example, in most motion control systems, in order to accelerate a mechanical load under control, more force is required from the actuator.If a velocity loop PID controller is being used to control the speed of the load and command the force being applied by the actuator, then it is beneficial to take the desired instantaneous acceleration, scale that value appropriately and add it to the output of the PID velocity loop controller.