Optimization, vibration control and condition monitoring of collaborative robotic machining

使用机器人作为切削刀架从金属零件上去除材料被认为是一种有效和灵活的方法，用于越来越多的工业应用。基于机器人的加工系统已经成功地用于水电设备的维修，也是机械和航空航天制造领域各种过程自动化的有趣替代解决方案。与传统的计算机数控（CNC）加工相比，机器人加工具有几个优点。机器人加工系统不仅更灵活、可操作、操作成本更低，而且与工业CNC加工中心相比，它们还可以节省高达40%的生产工作空间。机器人加工也更适合在危险的工作条件下取代人工操作。

The use of robots as cutting tool holders to remove material from metal parts is recognized as an effective and flexible approach for an increasing number of industrial applications. Robot-based machining systems have been successfully used for the repair of hydroelectric equipment and are also an interesting alternative solution for automating various processes in the field of mechanical and aerospace manufacturing. Robotic machining offers several advantages compared to conventional computer numerical control (CNC) machining. Robotic machining systems are not only more flexible, manoeuvrable and less expensive to operate, they can also save up to 40% in production workspace compared to industrial CNC machining centers. Robotic machining is also more suitable in hazardous working conditions to replace human operators. This program proposes a new robotic machining strategy using two hexapods for collaborative robotic machining operations. The main objective is to investigate the dynamics of the proposed robotic machining processes, to optimize the tool path and cutting parameters for feature machining of planar and curved surfaces and to propose a process monitoring approach. This research program is intended to increase the level of manufacturing readiness of the robotic machining. Within the scope of the proposed research program, we will study the feasibility of a new collaborative machining approach/architecture using two hexapods. We propose to model and study the dynamics of the collaborative robotic system, the material removal mechanism, and the linear and nonlinear chatter vibration problems associated with the machining process. Vibration control algorithms will be proposed to stabilize robotic machining operations and thereby increase the productivity and quality of the process. Moreover, a new process monitoring approach applied to the robotic machining process will be developed and implemented using wireless instrumented embedded force sensors for online control of the robotic machining. Regarding the hardware configuration, we propose a new build up using two hexapods. This set-up is expected to offer an increased dexterity for the machining of complex parts and easier design of tool path for chatter-free and singularity-free configurations by moving both end-effectors simultaneously and cooperatively. The originality of this research proposal lies in the development of a novel collaborative machining system using parallel robots, an active vibration control strategy and an online monitoring system using embedded sensors for robotic machining. This research will provide contributions for the development of flexible and reconfigurable manufacturing systems and increase the application versatility of robots in industrial automation.