Robust Control of Modular Gun Propellant Select Mechanism with Unknown Dead-Zone

Abstract

Modular gun propellant select mechanism is an important subsystem of the gun automatic loading system, it is used to select desired amount of modular gun propellants, which are placed in a receptacle. The distance between two adjacent propellants is short because of the small storage space, so robust precision control is important and necessary to reliably select the desired amount of propellants. The mathematical model is obtained, and nonlinear characteristics such as nonlinear friction, transmission clearance, and unknown dead-zone and so on are also considered. To simplify the problem, a simplified disturbing force model is used to replace the impulse force when the propellant, which is fastened by a hook, is freed. Considering that the system parameters are time-varying and also the system is influenced by an additional disturbance, a fuzzy sliding mode controller is designed by using the sliding mode control theory and fuzzy control theory together, the sliding mode control forces the system to move along the desired trajectory while the fuzzy control is used to reduce the chattering. Three situations, that are select one, three and five propellants respectively, have been studied, simulation results show that the presented fuzzy sliding mode controller is not only insensitive to the system parameters change and the additional disturbances, but also has high position precision.