How quick can cycle time be before something fails?

Robot cycle time and health and safety are often conflicting factors because, although tasks should be completed as quickly as possible to achieve low lead times, processes frequently have limits where dangerous failures occur.

This project investigated the parameters that define these equipment failures in robotic machining of aluminium to identify how fast this can be done before cutting tools break and cause a health and safety risk as well as process downtime. This is key to addressing limitations of using robotics for machining rather than conventional CNC machine tools. Experiments involved running a series of dynamic tests on a hexapod-format robot at various positions in its working envelope. These tests involved measuring frequency responses after hammer impacts at the robot actuators and end effector in various use-cases to determine stability.

Results allowed stiffness characteristics to be inferred and therefore the likelihood of excessive vibration, which leads to cutting tool breakage. The outcome of this work was improved machining productivity and avoidance of tool failures, which lead to improvements in health and safety.

This work was presented at the High Speed Machining conference, held in Prague in 2014, and published in its proceedings. For more information please contact us or see the full article:

Effects of Hexapod Robot Dynamics in Milling