Gravity Compensation Control of a 2-DOF Spherical Parallel Manipulator

Resumen: In this work, a gravity compensation controller for a 2-DOF spherical parallel wrist with a camera mounted on the end effector is derived in order to reduce the joints positioning error given by a PD controller during camera orientation. Here, the camera body is considered as a 2D pendulum with origin at the sphere center and referenced to the end effector stable plane. Thus, the gravity compensation torques for the joints are obtained by following the Euler-Lagrange methodology through inverse kinematics. Significant reduction in magnitude and variability of the joints positions errors demonstrates the enhanced performance and validity of the present approach. Experimental controller implementation is described and a discussion on the results is given.

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Azgad Casiano-Ramos, Aldimir Mora-Sota, Hugo G. Gonzalez-Hernandez, Antonio Benítez-Rui, María D. Guevara-Espinosa & Jesús M. Muñoz-Pacheco. Gravity Compensation Control of a 2-DOF Spherical Parallel Manipulator. Memorias del Congreso Nacional de Control Automático, pp. 821-826, 2019.

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Robótica y Mecatrónica

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