Automatic Self-Calibration of Suspended Under-Actuated Cable-Driven Parallel Robot using Incremental Measurements
This paper focuses on the problem of the initial-pose estimation by means of proprioceptive sensors (self-calibration) of suspended under-actuated Cable-Driven Parallel Robots (CDPRs). For this class of manipulators, the initial pose estimation cannot be carried out by means of forward kinematics only, but mechanical equilibrium conditions must be considered as well. In addition, forward kinematics solution is based on cable-length measurements, but if the robot is equipped with incremental sensors cables’ initial values are unknown. In this paper, the self-calibration problem is formulated as a non-linear least square optimization problem (NLLS), based on the direct geometricostatic problem, where only incremental measurements on cable lengths and on swivel pulley angles are required. In addition, a data acquisition algorithm and an initial value selection procedure for the NLLS are proposed, aiming at automatizing the self-calibration procedure. Simulations and experimental results on a 3-cable 6-degree-of-freedom robot are provided so as to prove the effectiveness of the proposed methodology.
KeywordsCable-driven parallel robots Underconstrained robots Underactuated robots Homing Self-calibration
Unable to display preview. Download preview PDF.
- 1.Abbasnejad, G., Carricato, M.: Direct geometrico-static problem of underconstrained cable-driven parallel robots with n cables, IEEE Transactions on Robotics, vol. 31, no. 2, pp. 468-478 (2015).Google Scholar
- 7.Idá, E., Berti, A., Bruckmann, T., Carricato,M.: Rest-to-rest trajectory planning for planar underactuated cable-driven parallel robots, in Cable-Driven Parallel Robots, C. Gosselin, P. Cardou, T. Bruckmann, and A. Pott, Springer, pp. 207-218 (2018).Google Scholar
- 8.Lau, D.: Initial length and pose calibration for cable-driven parallel robots with relative length feedback, in Cable-Driven Parallel Robots, C. Gosselin, P. Cardou, T. Bruckmann, and A. Pott, Springer, pp. 140-151 (2018).Google Scholar
- 9.Lin, J., Liao, G.: Design and oscillation suppression control for cable-suspended robot, in 2016 American Control Conference, pp. 3014-3019 (2016).Google Scholar
- 10.Merlet, J.P.: Direct kinematics of cdpr with extra cable orientation sensors: The 2 and 3 cables case with perfect measurement and ideal or elastic cables, in Cable-Driven Parallel Robots, C. Gosselin, P. Cardou, T. Bruckmann, and A. Pott, Springer , pp. 180-191 (2018).Google Scholar
- 11.Miermeister, P., Pott, A.: Auto calibration method for cable-driven parallel robots using force sensors, in Latest Advances in Robot Kinematics, J. Lenarcic and M.Husty, Springer, pp. 269-276 (2012).Google Scholar
- 12.Miermeister, P., Pott, A., Verl, A.: Auto-calibration method for overconstrained cabledriven parallel robots, in ROBOTIK 2012; 7th German Conference on Robotics, pp. 1-6 (2012).Google Scholar
- 13.Nubiola, A., Slamani,M., Joubair, A., Bonev, I.A.: Comparison of two calibration methods for a small industrial robot based on an optical CMM and a laser tracker, Robotica, vol. 32, no. 3, pp. 447-466 (2014).Google Scholar
- 14.Pott, A.: An algorithm for real-time forward kinematics of cable-driven parallel robots, in Advances in Robot Kinematics: Motion in Man and Machine, J. Lenarcic and M. M. Stanisic, Springer, pp. 529-538 (2010).Google Scholar
- 15.Pott, A.: Influence of pulley kinematics on cable-driven parallel robots, in Latest Advances in Robot Kinematics, J. Lenarcic and M. Husty, Springer, pp. 197-204 (2012).Google Scholar
- 16.Pott, A., Mütherich, H., Kraus, W., Schmidt, V., Miermeister, P., Verl, A.: IPAnema: A family of Cable-Driven Parallel Robots for Industrial Applications,in Cable-Driven Parallel Robots, T. Bruckmann and A. Pott, Springer, pp. 119-134 (2013).Google Scholar
- 17.Zarei, M., Aflakian, A., Kalhor, A.,Masouleh,M.T.: Oscillation damping of nonlinear control systems based on the phase trajectory length concept: An experimental case study on a cable-driven parallel robot, Mechanism and Machine Theory, vol. 126, pp. 377-396, (2018).Google Scholar