Designing Fast and Smooth Trajectories in Collaborative Workstations

Abstract

Collaborative robotics is one of the main drivers of the fourth industrial revolution. However, its introduction implies new challenges related to the mechanical risk they may represent and the psychological stress that they can induce on people. In order to reduce these risks, countermeasures like velocity limits and smooth trajectories have been implemented. Nevertheless, from these solutions excessively slow motions which cannot be integrated in fast work cycles may derive. In this letter, we propose a novel trajectory planning methodology which aim is to reduce these risks and minimize the execution time. We rely on available literature to identify a family of psychologically safe paths and apply on it a novel reparametrization algorithm capable of minimizing the execution time while limiting the mechanical risk represented by the robot. A numerical implementation of the method is discussed and experimental results reported as prove of the effectiveness of the idea.