Kinematic Model Building and Servo Parameter Identification of 3-HSS Parallel Mechanism

Abstract

Aiming at a parallel mechanism with three degrees of freedom, a method for dynamic model building and the parameter identification of its servosystem is presented. First, the reverse solution models of position, velocity, and acceleration of parallelogram branch structure are deduced, and then, its dynamic model of a rigid body is set up by using the virtual work principle. Based on the above model, a method to identify the servo parameter of the parallel mechanism is put up. In this method, the triangle-shaped input with variable frequency is adopted to offset the disadvantages of pseudorandom number sequence in parameter identification, such as dramatically changing the vibration amplitude of the motor, easily impacting the motor that results in its velocity loop to easily open, and so on. Moreover, the rotary inertia can also be identified by the additive mass. The abovementioned data will lay a solid foundation for the optimum performance of the system in the whole workspace.