Experimental Evaluation of a Proximate Time-optimal Servo Control Scheme

The design of a set-point tracking control scheme is presented for typical double-integrator servo systems. The control scheme adopts the framework of proximate time-optimal servomechanism (PTOS). An extended state observer (ESO) is utilized to estimate the un-measured velocity signal and the unknown disturbance, and a disturbance compensation term is included in the PTOS control law. In the presence of speed constraint, a speed regulation stage is incorporated between the PTOS acceleration and deceleration stages. The control scheme is then applied to the position control loop in a permanent magnet linear synchronous motor servo system. Experimental verification has been conducted, based on the TMS320F28335 digital signal controller board. The results confirm that the proposed control scheme can track a wide range of target references fast and accurately, and has some robustness against disturbance and uncertainties.