Nonlinear Friction Adaptive Compensation Control of Hydraulic Manipulator Joint
Hydraulic manipulator plays a crucial role in heavy-duty tasks,but it commonly faces the issue of"sufficient power,insufficient precision"in high precision operations.Whether in fully autonomous or semi-autonomous modes,precise motion control is the fundamental requirement for achieving fine operations.Hydraulic manipulators often adopt a nonlinear drivetrain configuration where linear motion of the hydraulic cylinder drives the joint rotation,with friction arising from both the cylinders and rotational axes.However,current research mainly focuses on rotational friction while neglecting linear friction,leading to inadequate friction compensation in motion control.This paper establishes a nonlinear dynamic model of the hydraulic manipulator's drivetrain,specifically targeting model compensation control.It comprehensively considers the friction characteristics of both the cylinders and rotational axes and proposes a friction compensation control method.Combining the least-squares-based online parameter adaptation,direct/indirect adaptive robust controllers are designed.Finally,multiple sets of simulations are conducted to validate the effectiveness of the proposed control method in improving the control precision of the hydraulic manipulator's drive train.
万方数据
维普
