Impedance control methods and devices for two-degree-of-freedom parallel mechanisms are applied to robots.

Abstract

The invention relates to a method and apparatus for impedance control of a two-degree-of-freedom parallel mechanism applied to a robot. The method comprises a receiving step, by a distributed control unit, of a set of reference values ​​corresponding to the desired impedance response at the joint side and a set of feedback values ​​from at least one motor of the two-degree-of-freedom parallel mechanism. Based on the kinematic relationship between the joint space and the motor space, the distributed control unit determines the motor-side control parameters, including the motor-side reference rotation angle, the motor-side reference angular velocity, the motor-side stiffness coefficient, the motor-side damping coefficient, and the motor-side compensation torque. These motor-side control parameters are transmitted to at least one motor controller corresponding to at least one motor to calculate the motor-side control torque based on the motor-side control parameters and the set of feedback values.This method helps to better match the output response of a two-degree-of-freedom parallel mechanism with the desired impedance response at the joint side, reducing the influence of coupling characteristics in the two-degree-of-freedom parallel mechanism and facilitating implementation on real robots.

Images