Resonant Suppression Method Based on PI control for Serial Manipulator Servo Drive System

Abstract

A typical serial manipulator consists of a servo motor, a serial mechanism and an independent joint placed between the motor and the serial mechanism. Both the time-varying characteristics of the inertia of the serial mechanism and the flexibility characteristics of the independent joint are widely found in serial manipulator servo drive systems. These two characteristics not only increase the resonance magnitude of serial manipulators, but also affect the dynamic characteristics of the system. In order to obtain a stable output speed of serial manipulators, the variable parameters of a PI control strategy is applied to a serial manipulator servo drive system. Firstly, dynamic model of a serial manipulator servo drive system is established based on a two-inertia system. Then the transfer function from motor speed to motor electromagnetic torque is derived by the state-space equation. Furthermore, the parameters of the PI controller are designed and optimized utilizing three different pole assignment strategies with the identical radius, the identical damping coefficients, and the identical real parts. The results indicate that a serial manipulator servo drive system can obtain good dynamic characteristics by selecting parameters of the PI controller appropriately.

Control Method of Flexible Manipulator Servo System Based on a Combination of RBF Neural Network and Pole Placement Strategy

“…According to the literature [21], the pole placement strategy is adopted to configure the closed-loop transfer function's poles. The denominator polynomial of Equation ( 41) is written in the form shown in Equation ( 42):…”

“…In this paper, three indexes of maximum overshoot, peak time, and adjustment time are selected to evaluate the output characteristics [21]. Among them, the maximum overshoot reflects the system's dynamic accuracy; the peak time and adjustment time reflect the rapidity of the system.…”

“…Besides, the controller parameters also affect the output of the servo system for flexible manipulators. In literature [21,22], the controller parameters are optimized by adjusting the pole coefficients, and the rigid manipulators obtain a good output.…”

Fuzzy Adaptive Type II Controller for Two-Mass System

“…However, due to the fact that the closed-loop system is a fourth-order and there are (in PI) only two parameters, the independent location of the closed-loop poles of the system is not possible. This means that in this system the performance limitations are visible [6][7][8][9]. In [6], the analysis of the influence of the closed-loop poles' location on the drive performance is presented.…”

“…This extends the possible location of poles presented in [7], which can result in a better performance of the drive. The most detailed analysis of such a system is presented in [8]. The authors investigate three above-mentioned positions of the system closed-loop poles.…”