Command Shapers for Systems with Actuator Saturation

Command shapers are used to create inputs that move flexible systems without residual vibration. Originally developed for linear systems, command shapers use superposition of the inputs to cancel vibration and control the system response. Nonlinearities in the system degrade the performance of traditional command shapers. The presence of "hard" nonlinearities, such as actuator saturation, distort the desired commands before they reach the plant. Command shapers that avoid saturating the actuators, thus allowing the desired command to reach the plant in the original form, have been developed for a mass under PD control. These shapers are easier to compute than previously shown results. Simulations verify the efficacy of the new shapers.