3自由度气动串联机械手的关节控制

3自由度气动机械手属关节串联式机器人，机械手在运动过程中，转动惯量、重力矩及关节间的耦合力矩等参数都会发生较大变化，影响了机械手末端的运动精度。针对这些问题，利用拉格朗日方程对机械手3关节进行动力学分析，得到多关节联动时单关节力矩方程。以腰部关节为例，通过对关节动力机构的数学模型线性化处理，采用状态反馈极点配置方法进行控制器设计，试验表明具有一定鲁棒性，但存在一定静态误差。分析产生误差的原因主要是干扰力矩的影响，根据单关节规划路径通过动力学模型得到补偿力矩，利用输入前馈对关节实施动态补偿。试验验证了方法的有效性，从结果可以看出，该组合控制策略抑制了扰动，提高了轨迹跟踪精度。

Joint Torque Control for the Pneumatically Robotic Manipulator with 3 Degrees of Freedom

Pneumatically robotic manipulator with 3 degrees of freedom belongs to serial mechanisms. During the movement of robotic manipulator, parameters such as rotation inertia, gravity torque and coupling torque between joints change greatly, which affects the motion precision of robotic manipulator. In order to solve the problems, dynamic analysis of manipulator’s three joints are carried out by using Lagrange equation. The waist joint is taken as an example to illustrate design of controller for joint. Through linearizing the mathematical model of power mechanism, the method of state feedback pole-assignment is applicable to the design of controller. The result shows that the single joint controller is robust, but there is certain static error. The error is mainly caused by the influence of disturbance torque. Dynamic compensation as the feed forward compensation for single joint controller is obtained by calculating single joint trajectory planning based on dynamic model. The experiment shows that the method is effective and improves the precision of the trajectory tracking.