摘要
针对机器人在外力作用下由结构变形引起的制孔位置沿工件表面滑移问题,研究应用机器人制孔的自由度冗余特性,通过优化机器人制孔姿态抑制末端位置滑移,提高机器人的定位精度.制孔程序中首末加工位置的机器人姿态通过有限元仿真优化确定.根据关节限位和干涉情况确定冗余自由度的优化范围并离散,应用机器人反解算法计算每一末端加工位姿对应的机器人姿态.调用相应的机器人仿真分析模型计算外力作用下的滑移变形,输出最小滑移变形对应的机器人姿态.对于中间加工位置处机器人制孔姿态的确定,提出以首末加工姿态为基准的姿态光顺算法,在保证机器人加工位置精度的同时提高机器人的关节运动效率.为考察机器人姿态优化与光顺方法的有效性,设计相应的验证实验.结果表明:优化后程序的制孔位置精度控制在0.2 mm以内,制孔效率从5孔/min提升至6孔/min,实现了机器人自动化制孔精度和效率的提升.
The end-effector faces with the problem of sliding movement along workpiece surface due to the structure deformation of robot under the external forces. The property of robot drilling redundancy was exploited to improve the hole position accuracy hy optimizing the robot posture to restrain the end-effector sliding. The first and last optimal drilling postures could be chosen by finite element simulation. Firstly, the robot postures was calculated by inverse kinematics solution after the optimized range of redundancy freedom was calculated and dispersed. Then, the sliding deformations of the robot in different postures were calculated and compared using the robot simulation model, so that the optimal drilling posture, in which the robot had the minimum deformation, could be obtained. In order to determine other drilling postures, a posture smoothness algorithm based on the first and last optimal drilling postures was proposed, thus guaranteeing the hole position precision and increasing the robot joint motions efficiency. Some experiments were designed to validate the feasibility of the proposed method. Results show that the hole position precision is effectively controlled to be within 0.2 mm and the drilling efficiency increased from 5 holes/min to 6 holes/rain. The required precision and high efficiency of robot automatic drilling are realized.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2015年第12期2261-2268,2275,共9页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(51305395)
中央高校基本科研业务费专项资金资助项目(2015FZA4005
2014FZA4003)
关键词
机器人制孔
加工冗余
有限元分析
姿态优化
姿态光顺
robot drilling
machining redundancy
finite element analysis
posture optimization
posture smoothness
