针对机器人与环境接触作业的需求,基于假设模态法建立了刚柔耦合动力学模型,并考虑环境参数不精确干扰,设计了自适应阻抗控制器,分析了其稳定条件。在 MATLAB/Simulink 中搭建了可对柔性机械臂进行自适应阻抗控制的仿真平台,计算了平面内二连杆柔性机械臂在含有三角形凹陷环境表面的接触运动和柔性变形模态。对比分析了刚性和柔性机械臂位控和力控效果及自适应项对控制响应的影响。基于Staubli机器人展开了实验。结果表明:柔性变形会使得机械臂的位控和力控效果变差;自适应阻抗控制会改善控制响应,对环境不确定具有鲁棒性。设计的自适应阻抗控制可实现柔性机械臂在不规则表面的稳定接触和运动。
For the operation contacting with obj ects,a rigid-flexible coupling dynamics model was established based on the assumed mode approach for two-link flexible manipulators.An adaptive im-pendence scheme was designed to compensate the environment uncertainties and the stability condition was analyzed.The control simulation platform was established using MATLAB/Simulink.The tip motion and deformation mode were computed under manipulator sliding on the surface with the trian-gular crack.Performances of position and force control were compared between the flexible and rigid manipulator,and performances of adaptive impedance control were analyzed.The physical experiment was conducted on Staubli robot.The results show the flexible deformation decreases the position and force control precision,and the adaptive impedance proposed can increase the response time.Adaptive impedance is robust to the environment position uncertainties and can realize the flexible manipulator stably contacting and moving on the not-flat surface.