基于力反馈的轴孔柔顺装配策略

Peg-in-hole compliant assembly strategy based on force feedback

针对目前工业自动化轴孔装配中因为轴孔位置偏差,直接装配导致失败的问题,提出了一种新型力反馈轴孔装配控制策略。该策略结合了传统的螺旋搜孔装配方法与力反馈轴孔装配策略的优点,装配流程分为孔外搜索、孔内调整和插入三个阶段。孔外搜索采用倾斜螺旋搜索,缩短了寻孔时间并增加了寻孔成功率;孔内调整使用力反馈装配策略,并简化了传统力反馈装配中接触状态的识别种类和算法,增强了识别的准确性。装配过程机器人采用导纳控制的柔顺控制算法。通过非参数统计实验表明该策略虽比螺旋搜索直接装配耗时长一点,但成功率更高,而且对位置偏差敏感性低,鲁棒性更强。对无倒角,间隙较小的精密轴孔装配有很高的应用价值。

Aiming at the problem of the position deviation of peg and hole as well as direct assembly lead to failure in the current industrial automatic peg-in-hole assembly,a new force feedback peg-in-hole assembly control strategy was proposed.This strategy combined the advantages of the traditional spiral search assembly method and the force feedback peg-in-hole assembly strategy.The whole assembly process was divided into three stages:search outside the hole,adjustment inside the hole and insertion.The search outside the hole adopted the inclined spiral search,which shortened the hole search time and increased the success rate of hold researching.The adjustment inside the hole used the force feedback assembly strategy and simplified the identification types and algorithms of the contact state in traditional force feedback assembly,and enhanced the accuracy of recognition.The robot adopted the compliant control algorithm of admittance control in the assembly process.Non-parametric statistical experiments show that although this strategy takes a little longer than the spiral search assembly,it has a higher success rate,low sensitivity to position deviation,and stronger robustness.It has high application value for precision peg-in-hole assembly without chamfering and with small clearance.