Design of a generic fuzzy controller for electrohydraulic steering

Abstract

Fuzzy control, unlike most mathematical model based control systems, can mimic a human operator's way of thinking in controlling a plant. The ability of a fuzzy system to mimic a human operator's thought process makes it possible to design a generic controller for multiple plants utilizing the same basic decision-making logic. This paper presents a design method for generic fuzzy steering controller for similar types of wheeled vehicles. Test results proved that a well-designed generic fuzzy steering controller could be directly applied to different types and/or models of analogous vehicles with limited recalibration.

Adaptive Sliding Mode Control Method Based on Nonlinear Integral Sliding Surface for Agricultural Vehicle Steering Control

“…Proof. According to the nonlinear integral sliding surface (10) and the steering system model (6), the system error model during the sliding mode movement phase is obtained as follows:̈1…”

“…According to Theorem 1, the closed-loop control system not only is stable but also has variable damping ratio ∈ [ min , max ] by using the designed nonlinear integral sliding surface (10). Therefore, we can acquire the desired closedloop system properties that the closed-loop steering system has relatively smaller damping ratio to accelerate the output response speed during the initial phase of the sliding mode movement and has relatively bigger damping ratio to avoid system output overshoot and ensure the system stability as the output approaches the desired command.…”

“…Zhou [7] and Gao et al [8] design agricultural vehicle steering driving systems based on step motors and, respectively, utilize the Bang-Bang control method and the PID method to develop the steering controllers of agricultural vehicles. For the second driving approach, Zhang et al develop automatic steering controllers based on the fuzzy control method for agricultural vehicles, and the control performances are verified by the practical steering control experiments [9][10][11][12]. Some researchers also use the PID method to design the steering controllers for the steering system which is implemented by the second driving approach [13,14].…”

Development of Electrohydraulic Steering Control System for Tractor Automatic Navigation

“…RoviraMás and Zhang [22] designed an electrohydraulic steering control system for agricultural vehicles and developed a fuzzy steering controller with this electrohydraulic steering control system. Zhang [23] designed a generic fuzzy steering controller for an agricultural tractor with a hydraulic steering actuator and an electrohydraulic steering control valve, and the controller was tested on a hardware-in-loop electrohydraulic steering simulator and on two agricultural tractors.…”