A novel methodology to improve robotic contour following by using radial-compliant pneumatic spindles

Abstract Ensuring consistent contact between the tool and the workpiece is a key challenge in robotic finishing operations, especially when dealing with positioning errors or morphological variations in the workpiece. Tool compliance has become a widely adopted strategy to tackle this issue, offering greater adaptability in these scenarios. At the same time, feed rate plays a fundamental role in process performance; however, achieving a uniform feed rate is not always possible due to robot limitations in executing the programmed trajectory. This study introduces an innovative approach that leverages tool compliance systems not only to maintain contact but also to evaluate the performance of contouring trajectories with varying discretization levels, all without the need for additional measurement equipment. Thus, by continuously monitoring radial compliance, the proposed methodology quantifies both the contact consistency with the workpiece and the time required to complete the motion. The insights gained from this process enable an objective assessment of contour following, balancing speed, and positioning accuracy and provide a practical tool for optimising trajectory design. This approach provides a practical solution for optimising trajectory design and promotes smoother and more fluid transitions between control points, establishing a new standard for precision and efficiency in robotic finishing operations.