Generating the optimum dynamic trajectory of a hybrid cable-serial robot

Abstract

In this work, a geometric path planner and a dynamic controller are designed for a hybrid cable serial robot. The shortest path between two positions in presence of obstacles, is found using a geometric path planner then a dynamic joint space controller finds the fastest way to reach the goal while ensuring that cables tensions stay positive. The goal of this controller is to maintain the tensions in the cables in a bounded interval between a minimum and a maximum value. By limiting the maximum acceleration of the different links, the controller ensures that the tensions stay within an allowable range. However, these constraints limit the maximum speed reachable by the robot, and the controller tries to find the fastest solution, which minimizes the total elapsed time while respecting the constraints. In conclusion, the trajectory planner finds the shortest path and the dynamic controller finds the minimum total elapsed time for this path.