Research on port AGV trajectory tracking control based on improved fuzzy sliding mode control

Abstract

The operating environment of the port AGV is outdoors in the coastal area. There are complex and changeable environmental impacts such as rainfall, wind erosion, and salt erosion, which cause more disturbances to the port AGV. Aiming at the problem of the influence of environmental disturbance on trajectory tracking accuracy during the operation of port AGV, this paper proposes a control method based on fuzzy control theory and sliding mode variable structure control theory. Firstly, a two-degree-of-freedom dynamic model of AGV in port environment is established on the premise of accurately describing the dynamic characteristics of the vehicle and reducing the requirements for hardware and software. Secondly, for the tire model, the tire model formula constructed by the magic formula proposed by Pacejka with high fitting accuracy and simple modeling is used to establish the tire model. Thirdly, aiming at the chattering problem in sliding mode control, sliding mode variable structure control is designed, and fuzzy controller is added to control the change of switching gain coefficient. Finally, for the actual operating environment of the port, the Gaussian disturbance is used to simulate the external disturbance, and the controller model designed in various ways is built and simulated by Matlab / Simulink software. The experimental results show that the proposed algorithm is superior to the control group in response speed, anti-interference ability and reducing chattering. Compared with the traditional control method, the steady-state time of the position tracking method is increased by 73.41 %, and the error generated in the disturbance stage is 1.8 % of the initial error. The speed tracking enters the Gaussian disturbance stage after the steady state, and the error is less than 1 % of the initial error, which achieves the purpose of reducing chattering, realizes the optimization of the traditional sliding mode variable structure control, and verifies the feasibility of the algorithm in the future practical application.