A Study on the Control of Multi-Input Hydraulic System for Robot Leg using LQR Technique

Yoo, Sam-Hyeon; Lim, Soo-Chul

Journal of the Korea Institute of Military Science and Technology 2009;12(4):540-547.

Sam-Hyeon Yoo, Soo-Chul Lim

Korea Military Academy

LQR 기법을 이용한 로봇다리의 다중입력 유압시스템 제어에 관한 연구

유삼현, 임수철

육군사관학교 무기.기계공학과

Abstract

In the near future, military robots are likely to be substituted for military personnel in the field of battle. The power system of a legged robot is considerably more complex than the one used for a land vehicle because of the coordination and stability issues due to the large number of degree of freedom. In this paper, a servovalve-piston combination system for a straight-line motion of robot leg is modeled as three degree of freedom based on double inputs and single output transfer function. The output is the displacement of piston from neutral. The inputs are valve displacement from neutral and arbitrary load force in this system. LQR(Linear Quadratic Regulator) technique is applied in order to achieve robust stability and fast responses of the system. The Kalman filter loop, rejection of disturbance and noise, riccati equation, filter gain matrix, and frequency domain equality are analyzed and designed.

Key Words: Linear Quadratic Regulator(LQR), Filter Gain Matrix, Servovalve-Piston Combination System, Legged Robot