基于虚拟力概念的柔性臂空间机器人模糊退步自适应控制算法设计

讨论了漂浮基柔性臂空间机器人系统的动力学模拟、运动轨迹跟踪控制算法设计及柔性振动主动抑制。采用多体动力学建模方法并结合假设模态法,建立了漂浮基柔性臂空间机器人的系统动力学模型。基于该模型,针对系统惯性参数未知情况,提出了刚性运动基于模糊基函数网络自适应调节的退步控制算法,以完成柔性臂空间机器人载体姿态及机械臂各关节铰的协调运动。然后,为了主动抑制系统柔性振动,运用虚拟力的概念,构造了同时反映柔性模态和刚性运动轨迹的混合期望轨迹,通过改造原有的控制算法,提出了基于虚拟力概念的模糊退步自适应控制算法;这样不但保证了之前刚性运动控制方案对模型不确定的鲁棒性,而且能主动抑制柔性振动,从而提高了轨迹跟踪性能。理论分析及数值仿真算例均表明了控制方法的可行性。

Fuzzy adaptive algorithm using backstepping controller for flexible arm space robot based on virtual control force conception

This paper discusses dynamics modeling, motion trajectory tracking control algorithm design and flexible vibration active suppression of free-floating flexible arm space robot system.We take the method of multibody dynamics modeling and combine with assumed mode method to set up system dynamics model for free-floating flexible arm space robot.Based on said model, and aiming at the situation of system inertial parameter unknown, we propose that rigid motion based on fuzzy basis function network adaptive adjust algorithm using backstepping controller, thus to fulfill coordinated movement of base's attitude of flexible arm space robot and each joint hinge of robot arm.Then order to actively suppress system flexible vibration, the concept of virtual force is been used to structure mixed expected trajectory that reflect both flexible mode and rigid motion trajectory.By transforming original control algorithm, we propose fuzzy adaptive control algorithm using backstepping controller that based on the concept of virtual force.So it not only guarantees the uncertain robustness of previous rigid motion control method against model, but also actively suppresses flexible vibration, thus to improve the tracking performance of trajectory.Theory analysis and numerical simulation example both testify the reliability and availability of this control scheme.