Real-time trajectory scaling for robot manipulators

Recent developments in industrial robotics use real-time trajectory modification to improve throughput and safety in automatic processes. Online trajectory scaling is often used to this purpose. In this paper, we propose a feedback trajectory scaling approach that is able to recover from the delay introduced by the speed modulation and improves the path-following performance thanks to an additional inner control loop. Simulation and experimental results on an industrial 6-degree-of-freedom robot show the effectiveness of the proposed approach compared to standard algorithms.

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