Robust Motion Control of Flexible Systems Using Feedforward Forcing Functions

Forcing functions are developed to produce vibration-free motions in flexible systems. These forcing functions are constructed from ramped simusoid basis functions so as to minimize excitation in a range of frequencies surrounding the system natural frequency. A closed-loop control system is developed which utilizes these forcing functions to generate a reference profile, and also feeds them forward directly to the system to enhance closed-loop bandwidth. Simulation results indicate superior vibration attenuation compared to the minimum-energy forcing function, especially when some error in natural frequency exists.