A General Framework for Designing SISO-Based Motion Controller With Multiple Sensor Feedback

This paper proposes N-degree-of-freedom (NDoF) control for single-input and single-output based systems. This method relaxes the water-bed effect, which limits the capacity to suppress disturbances and noise using multiple sensors. The system's design procedure for the control system and nominal stability conditions are introduced. NDoF control is then compared with classical two-DoF control and with Kalman filter using simulations and experiments of motor systems with an encoder and an accelerometer. The results indicate that N-DoF control achieves an enhanced disturbance and an oscillation suppressing performance simultaneously. Moreover, N-DoF control is applied to two-mass systems and verified by using numerical simulation. The characteristics are introduced and compared with several conventional approaches. The results suggest that N-DoF control incorporates all the characteristics of the other methods, and its disturbance and vibration suppression capability is demonstrated.