An Improved Quasi-continuous Controller with Disturbance Observer for Rotational Shell Magazine Position Control

This article proposes a new control scheme by combining an improved quasi-continuous controller (IQCC) and sliding mode disturbance observer (SMDO) for automatic chain shell magazine (ACSM) position control. Unlike conventional quasi-continuous controller (QCC), the new IQCC switches between two formulas according to the value of the first derivative of sliding variable. The influence of parameters design in IQCC on the control effect is further discussed. By combining IQCC with SMDO, the design of controller gain is independent of the uncertainties bound. The close-loop stability of combined scheme is proved by a Lyapunov function. Compared with QCC, IQCC performs better in convergence rate and chattering restraining. The scheme could achieve satisfied control effects for nonlinear systems with uncertain disturbances. Simulation and experimental results verify the superiority of the proposed controller over QCC and proportional integral (PI).