A Model Identification and Adaptive Control Method for Hydraulic Manipulator

Abstract

The invention discloses a model identification and self-adaptive control method of a hydraulic manipulator, comprising the following steps: S1, establishing a dynamic model of the manipulator including unknown parameters; S2, using an NFO algorithm to design the excitation of the manipulator under specific physical constraints track and perform excitation experiments to identify unknown parameters in the dynamic model of the manipulator; S3, design an adaptive backstep controller, and use new control variables to revise the control output of the adaptive backstep controller. The invention uses the joint angle and torque information, adopts the neighborhood optimization algorithm to design the excitation trajectory with specific physical constraints to carry out excitation experiments, and identifies the Lagrangian model parameters of the two-degree-of-freedom hydraulic manipulator; The parameter adaptive backstepping controller is designed, which can effectively adapt the unstable hydraulic parameters dynamically, and finally realize the stable control of the mechanical arm by the hydraulic system.

Description

technical field [0001] The invention belongs to the technical field of hydraulically controlled manipulators, in particular to a model identification and self-adaptive control method of a hydraulic manipulator. Background technique [0002] Electrohydraulic servo system has been widely used in electromechanical engineering because of its high load efficiency and large output power. However, there are uncertainties in hydraulic parameters due to unknown viscous damping, load stiffness, control fluid volume variation, valve physical properties, bulk modulus, and oil temperature variation. These uncertain hydraulic parameters will bring many problems to the actual hydraulic control system, such as causing the control accuracy and control stability of the system to fail to meet the predetermined requirements. Aiming at this problem, a parameter adaptive controller is designed to solve the uncertainty of electrohydraulic parameters and external interference. In addition, the me...

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Problems solved by technology

[0004] With the increasing application of hydraulic robot arms in the engineering field, it is more and more urgent to solve the problem of hydraulic parameter instability, and the accuracy requirements for mechanical arm parameter identification are getting higher and higher; and the existing model identification methods often fail to meet the requirements. The identification accuracy and error convergence speed required by the actual requirements, but the lack of research on model identification methods with high accuracy and fast convergence

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