自由浮动冗余度空间机器人的混沌识别与控制

Chaotic Recognise and Control for Free Floating Redundant Space Robot

建立空间冗余度机器人基于关节空间的PD控制下系统运动学方程,推导了系统的广义雅克比矩阵,指出空间机器人和地面机器人在运动学上的不同。以空间三自由度机器人为例,应用混沌数值分析方法中的相图法,Poincare截面法和最大Lyapunov指数法对上述模型进行了计算机仿真。研究发现,不同的PD控制参数和末端执行器期望轨线,均能导致系统的混沌运动。对以上混沌系统设计状态延迟反馈控制器,仿真研究表明,在适当参数下系统由复杂的混沌运动转变为规则的周期运动。该研究为解决空间冗余度机器人关节"漂移"问题提供了新方法。

A kinematic formula based on the joint space about the Free Floating single arm redundant space robot is developed, a PD negative feedback controller is designed and according to the system＇ s Generalized Jacobian Matrix （GJM） , the differences between the Free Floating Space Robot and the common robot are pointed out. Secondly, under the PD controller, the simulation results of the space robot as the end-effector traces a closed-path repeatedly in its work space are given, in which several chaotic numerical analysis methods, such as Phase diagram means, Poincare section method, and the Maximum Lyapunov Exponent algorithm were used. According to the research, the space robot exhibits undesirable chaotic joint motion under the pseudoinverse control. Thirdly, the study also demonstrates that chaotic motions of robot with kinematical redundancy can be turned into regular motion when the state-delayed feedback controller is applied with some appropriate parameters. This paper provides a new insight which is helpful to solve the repeatable problem of Free Floating redundant space robot.