考虑碰撞的冗余串联机器人冲击运动分析与优化  

Impact Motion Analysis and Optimization of Redundant Serial Robot Considering Collision

作　　者：畅博彦[1,2] 朱永杰 金国光 宋艳艳[1,2] 李晓宁 路春辉 CHANG Boyan;ZHU Yongjie;JIN Guoguang;SONG Yanyan;LI Xiaoning;LU Chunhui(College of Mechanical Engineering, Tianjin Polytechnic University, Tianjin 300387, China;Tianjin Key Laboratory of Advanced Mechatronics Equipment Technology, Tianjin 300387, China)

机构地区：[1]天津工业大学机械工程学院,天津300387 [2]天津市现代机电装备技术重点实验室,天津300387

出　　处：《农业机械学报》2019年第9期413-420,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51475330);天津市自然科学基金项目(17JCQNJC03900);天津市教委科研计划项目(2018KJ205);天津市高等学校创新团队培养计划项目(TD13-5037)

摘　　要：根据操作环境和使用工况的不同,将碰撞问题划分为无约束碰撞问题和有约束碰撞问题,有约束碰撞问题又包括定点碰撞和动点碰撞。首先,基于Lagrange方程建立串联机器人系统的冲击动力学模型,并结合经典碰撞理论与恢复系数方程,推导了碰撞时系统的外部冲量求解模型。其次,针对无约束碰撞问题,在冲击动力学分析的基础上,建立了机器人发生碰撞时的冲击运动映射关系,提出了冲击运动映射矩阵的概念,并以此为基础构造机器人的冲击运动性能评价指标,用以评价系统在外部冲击作用下保持运动稳定性的能力。最后,分析定点碰撞和动点碰撞的已知条件,提出以碰撞时产生的外部冲量最小为目标,对机器人的碰前位姿进行优化,并以平面三连杆机器人为示例,分别进行无约束碰撞和有约束碰撞的冲击运动分析与优化设计。研究结果表明,机器人在处于或接近奇异位型时抵抗外部冲击的能力会显著降低,其结构参数对系统冲击运动性能有较大影响;通过对机器人的碰前位姿进行优化,可有效减小定点碰撞和动点碰撞时所产生的外部冲量,有利于提升系统运行的稳定性和安全性。According to the different operating environment and working conditions, the collision can be divided into unconstrained collision and constrained collision, including immovable-point collision and movable-point collision. Firstly, the impact dynamics model of the serial robot system was established based on Lagrange equation, and the solving model of external impulse was derived from classical collision theory and recovery coefficient equation. Secondly, with respect to unconstrained collision, the concept of impact motion mapping matrix was proposed on the basis of impact dynamics analysis, and the evaluation index named impact motion performance was constructed for evaluating the ability to maintain motion stability under external impulse action. Finally, the ideas and methods for solving problems of immovable-point collision and movable-point collision in kinematically redundant serial robot were transformed into optimizing robot’s pre-collision posture by choosing the minimum external impulse generated during the collision as the objective for optimization. Taking the planar three-bar robot as an example, the impact motion analysis and optimization design of unconstrained collision and constrained collision were carried out respectively. The results showed that the external impulse would rise significantly when robot was in or near singularity, and its structural parameters had a great effect on the impact motion performance. The external impulse generated from collision can be reduced effectively by means of pre-collision posture optimization, which was very useful for improving the stability and security of the system.

关 键 词：串联机器人 碰撞 冲击运动 性能指标 优化设计 

分 类 号：TH112.1[机械工程—机械设计及理论]