Integrated Design of Robotic Workcells for High Quality Machining

Purpose:Robotic workcells provide high flexibility and reconfigurability, cost effectiveness and user friendly programming for many industrial applications but still lack in accuracy, so important fields of application such as mechanical machining are currently covered by very expensive and rigid systems (machining centers). The present work investigates the possibility to extend the use of industrial robots to perform high quality machining.Method:The proposed method is focused on the enhancement of robotic machining accuracy through an integrated design method, based on robotic process simulation and tailored design of mechanical apparatus and software modules for robot control and programming. Advanced techniques for machining strategy validation, automatic robot path generation, workcell calibration, robot code commissioning are concurrently adopted.Result:Integrated design tools are fully exploited to define the system behavior, to simulate the whole process, to propose alternative machining set-ups and quickly generate and test parametric programs. The design method is finally applied to design a robotic workcell family for grinding special austenitic manganese steel casts, characterized by severe working conditions as high tool wear, high cutting forces, high vibrations due to surface hardness and non-repetitive shape variations in geometry and features.Discussion & Conclusion:Experimental results demonstrate enhanced performance of robotic workcells and final quality, due to minimization of tool vibration, increasing of robot stiffness and higher manufacturing flexibility, thanks to the capability of adapting robot paths to workpieces.