Adaptive sliding-mode control for motor-toggle servomechanism

In this study, the dynamic responses of an adaptive sliding-mode controlled motor-toggle servo mechanism are described. The servomechanism is a toggle mechanism actuated by a permanent magnet (PM) synchronous servomotor. First, a newly-designed sliding-mode controller, which is insensitive to uncertainties including parameter variations and external disturbance, is introduced. Then, to overcome the two main problems with sliding-mode control, i.e., the assumption of known uncertainty bounds and the chattering phenomenon in the control effort, an adaptive sliding-mode controller is investigated to control the motor-toggle servomechanism. In the adaptive sliding-mode controller, a simple adaptive algorithm is utilized to adjust the uncertainty bounds in real-time. Simulated and experimental results due to periodic step and sinusoidal commands show that the dynamic behaviors of the proposed controllers are robust with regard to uncertainties.