机器人镗孔加工系统稳定性分析

Stability analysis of robot boring system

为了解决大型飞机装配现场主起落架交点孔的镗孔精加工问题,提出了采用六自由度工业机器人及专用末端执行器组合的创新解决方案。压脚是抑制机器人镗孔加工系统颤振的核心环节。通过对施加压脚前后的机器人镗孔加工系统进行动力学建模,对系统的稳定性进行分析,得出压脚装置对加工系统稳定性叶瓣图的影响。最后通过实际镗孔加工实验验证了机器人镗孔系统在不同压脚压力下的加工稳定性,表明合理的压脚压力可提高稳定切深,拓展加工稳定区域,有效避免加工颤振。

In order to perform the finish boring procedure of the aircraft landing gear＇s junction hole in the aircraft assembly field, a six axis industrial robot with a special designed end-effector system is proposed. The structure of pressure foot is a key technology to avoid chatter in this robot boring system. Through establishing an analytical model for stability limit predic- tion considering dynamical characteristics with and without pressure foot structure of the robot boring system, the chatter sta- bility lobes is achieved and studied to reveal the mechanism of the chatter depressing of the pressure foot. In addition, ex- periments are conducted to verify the rationality of the theoretical modeling under different pressure foot parameter condition. The analytical model and experiments show that the stability of the robot boring process can be enhanced by applying pres- sure foot system and choosing a rational pressure value. Stable machining area is expanded and chatter is avoided.