Multi-joint heavy-load hydraulic robot system and high-precision motion control method

Abstract

The invention discloses a multi-joint heavy-load hydraulic robot system and a high-precision motion control method. The multi-joint heavy-load hydraulic robot system consists of a power system, a sensing detection and data acquisition system, a computer control system and a mechanical arm body system. According to the high-precision motion control method, a dynamic model of a hydraulic robot is established, the system is compensated by considering the uncertainty of the system and modeling errors, and accurate tracking and control are achieved without changing parameters under different loading mass; the mechanically and hydraulically coupled system is layered through a nonlinear adaptive robust control method, an adaptive updating rate is introduced, the uncertainty of the system and theinfluence of external interference are overcome, the joint angle tracking error gradually tends to zero, and the transient state, the steady state performance and the anti-interference capability of the system are improved; the physical meaning of parameters of a controller is clear, the number of the parameters is small, and the tuning of the parameters of the controller is simple and has a theoretical basis; and the stability and convergence of the system are guaranteed by using a Lyapunov stability function, so that the overall robust stability of all signals is ensured.

Description

technical field [0001] The invention belongs to the field of hydraulic robot systems and controls, in particular to a multi-joint heavy-duty hydraulic robot system and a high-precision motion control method. Background technique [0002] Because of the advantages of larger load capacity, high load power ratio, simple transmission structure, and easy overload protection, hydraulic robots have broad application prospects in large load fields such as mines, aerospace, and nuclear industries. However, due to the strong nonlinearity of the hydraulic drive system, the uncertainty of the model and parameters brought about by the friction of the actuator, the saturation of the drive voltage, the direct change of the valve opening and closing, and the cover of the dead zone of the valve core, coupled with the heavy cargo belt Due to the high inertia, high pressure and large flow, the controllability of the manipulator is greatly reduced, the stability is difficult to prove, and the h...

AI Technical Summary

Problems solved by technology

However, due to the strong nonlinearity of the hydraulic drive system, the uncertainty of the model and parameters brought about by the friction of the actuator, the saturation of the drive voltage, the direct change of the valve opening and closing, and the cover of the dead zone of the valve core, coupled with the heavy cargo belt Due to the high inertia, high pressure and large flow, the controllability of the manipulator is greatly reduced, the stability is difficult to prove, and the high-precision controller is difficult to design.

For multi-joint hydraulic heavy-duty robots, traditional PID control cannot achieve strict stability proof and precise control, and the nonlinearity of the hydraulic system itself will have a great impact on the performance of PID control; The dynamic coupling between the connecting rods of the robot, especially in the case of high speed and heavy load, the dynamic coupling problem of the connecting rod is more serious; in addition, the parameters and disturbances of the robot system are often uncertain, in order to achieve high-precision motion control, it is necessary to consider the uncertainty and interference of the actual system

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