摘要
考虑了柔性关节的影响,研究了漂浮基柔性关节空间机械臂系统的动力学建模、运动控制以及柔性振动抑制问题。基于漂浮基柔性关节空间机械臂系统的简化模型,利用系统的动量、动量矩守恒关系和拉格朗日方程建立系统的动力学方程。为了同时实现空间机械臂运动轨迹的渐近跟踪和抑制由柔性关节引起的系统弹性振动,采用奇异摄动法将系统分解为相互独立的慢变和快变子系统。针对慢变子系统,提出模糊滑模控制律以实现空间机械臂期望运动轨迹的渐近跟踪。其中,模糊控制律的应用克服了滑模控制自身的抖振问题;针对快变子系统,采用速度差值反馈控制律来抑制柔性关节引起的系统弹性振动,保证了系统的稳定性。仿真时以平面两刚性杆、两柔性关节的漂浮基空间机械臂系统为例,证明了所提出的混合控制方法的有效性。
The dynamic modeling, motion controlling and elastic vibration suppression problem of free-floa-ting flexible-joint space manipulator were studied. Base on the simplified model of free-floating flexible-joint space manipulator system, the dynamic equations of the system were established by using the conser-vation of linear and angular momentums and the Lagrange equation. To realize the asymptotic tracking of space manipulator＇s motion trajectory and to suppress the elastic vibration caused by the flexible-joint, the system was decomposed into a slow subsystem and a fast subsystem based on the singular perturbation ap-proach. For the slow subsystem,a fuzzy sliding mode controller was designed to achieve the asymptotic tracking of the desired motion trajectory. And the fuzzy controller was used to overcome the chattering of the sliding mode controller. For the fast subsystem,a velocity difference feedback controller was proposed to suppress the system＇s elastic vibration caused by the flexible-joint, and thus to guarantee the system＇s stability. Simulation results on a free-floating flexible-joint space manipulator system with two rigid links and two flexible joints prove the efficiency of the proposed controller.
出处
《力学季刊》
CSCD
北大核心
2012年第4期635-641,共7页
Chinese Quarterly of Mechanics
基金
国家自然科学基金(11072061
10672040)
福建省自然科学基金(2010J01003)资助
关键词
漂浮基空间机械臂
柔性关节
奇异摄动
模糊
滑模
free-floating space manipulator
flexible-joint
singular perturbation
fuzzy
sliding mode
