Dynamic Point-to-Point Trajectory Planning of a Three-DOF Cable-Suspended Mechanism Using the Hypocycloid Curve

• Published in: IEEE/ASME transactions on mechatronics Vol. 23; no. 4; pp. 1964 - 1972
• Main Authors: Dion-Gauvin, Pascal, Gosselin, Clement
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acceleration; Cable-suspended robots; Degrees of freedom; dynamic workspace; Dynamics; IEEE transactions; Kinematics; Mechatronics; Planning; point-to-point trajectory planning; Trajectory; Trajectory planning
• ISSN: 1083-4435; 1941-014X
• DOI: 10.1109/TMECH.2018.2840051

This paper proposes a dynamic trajectory planning technique for the point-to-point motion of three-degree-of-freedom cable-suspended mechanisms. The trajectory path is inspired from a hypocycloid curve that is embedded in the plane defined by the acceleration vector at the initial point and the final point. The proposed motion ensures zero instantaneous velocity at each of the endpoints and continuity of the acceleration, while positive cable tensions are guaranteed through a proper choice of the number of arcs of the hypocycloid. The trajectory can be used in sequence to connect consecutive target points that may lie beyond the static workspace of the mechanism. Compared to previously proposed approaches, the technique developed in this paper produces very large regions of attainable target points. In particular, it is proven that horizontal trajectories are always feasible, for any prescribed target point. Simulation results of an example trajectory are included in order to illustrate the approach, along with a video demonstration of an experimental validation performed using a prototype.