Time scaling of cooperative multi-robot trajectories

An algorithm is developed to modify the trajectories of multiple robots in cooperative manipulation. If a given trajectory results in joint torques which exceed the admissible torque range for one or more joints, the trajectory speed is scaled so as to maintain all the torques within the admissible boundary. The trajectory scaling scheme described requires the use of linear programming techniques and is designed to accommodate the internal force constraints and payload distribution strategies. As the multirobot system is usually redundantly actuated, the actuator torques can be found from the quadratic minimization, which has the effect of lowering energy consumption for the trajectory. Several examples are given to show the effectiveness of the multirobot trajectory scaling scheme