Autonomous underwater robot propeller fault-tolerant control method based on sliding mode algorithm and thrust secondary adjustment

Abstract

The invention belongs to the technical field of autonomous underwater robot propeller fault tolerance, in particular to an autonomous underwater robot propeller fault-tolerant control method based ona sliding mode algorithm and thrust secondary adjustment; a sign function is replaced by a bipolar function, so that the self-adaptive adjustment of switching gain and the thickness of a boundary layer is realized, and a buffeting phenomenon of the slip-mode fault-tolerant control is weakened; a fault-tolerant control method combining sliding mode control and thrust secondary adjustment is adopted, so that the weight coefficient of a fault thruster in a propeller priority matrix changes along with the change of the fault degree, and the control voltage of the fault thruster is reduced; and a corresponding control compensation value is added into the control law to eliminate the influence of the deviation, and the purpose of fault-tolerant control is achieved. The problem of buffeting caused by the introduction of the sign function in sliding mode control of the autonomous underwater robot is solved, and the fault information provided by the fault diagnosis system is combined, so that the use level of the fault propeller is reduced, and the influence of the propeller faults on the system tracking performance is reduced.

Description

technical field [0001] The invention belongs to the technical field of fault tolerance of autonomous underwater robot propellers, and in particular relates to a fault-tolerant control method for autonomous underwater robot propellers based on sliding mode algorithm and secondary adjustment of thrust. Background technique [0002] The development of marine resources requires advanced technology and equipment. Underwater robots are currently the only equipment that can enter the deep sea. Autonomous underwater robots work in complex ocean environments without people and cables. Safety is the premise to ensure the smooth completion of tasks. Fault-tolerant control Technology is one of the key technologies to ensure the safety of underwater robots. [0003] The autonomous underwater robot system has strong coupling and nonlinear characteristics. Since the sliding mode control itself is a nonlinear control, it has good robustness and anti-interference performance, and has achieve...

AI Technical Summary

Problems solved by technology

The pseudo-inverse quadratic programming algorithm proposed by scholars can quickly obtain the optimal solution of the control quantity when performing control allocation, and express the weight adjustment function of the thruster as an exponential form of the failure degree coefficient, which greatly reduces the priority of using the faulty thruster. level, but the author of this article found in the experimental research that the thrust cannot be adjusted in time due to the excessive instantaneous change of the thrust, and the expected purpose cannot be achieved

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