具有非驱动关节机器人模型的研究

Model of Underactuated Robot

以具有非驱动关节的水平两自由度机械手 (大臂为驱动臂 ,小臂无驱动、自由 )为对象 ,建立了其动力学数学模型 ,对其非完全约束 (约束条件为不可积 )情况进行了分析 ,在此基础上 ,利用解非线性方程的有效方法一平均值法对模型进行了处理 ,得到了与原系统动力学性能基本等价的平均系统 ,使模型得到简化 ,通过非线性系统相平面分析的方法 ,对原模型与简化后的平均系统模型在扰动作用下的特性进行了分析 ,得到了满意的仿真结果 ,验证了简化方法的有效性 。

A dynamic model is developed for an underactuated robot with the first joint actuated and the second joint free. The property of the non_holonomic constraint that the differential constraint is non_integrable is analysed. The model is simplified through obtaining the average system of the underactuated robot using an averaging method efficient to deal with a nonliner system. Simulation results show that the real system and the average system have the same trajectory in the phase plane under the disturbance of periodic input of the actuated joint of the robot. So the work we approximate the system by the averaging method is effective and the model of average system is useful for position control of an underactuated robot.