Admittance Control with FSR Sensors in a ROS 2 Node for Exoskeleton Rehabilitation
DOI:
https://doi.org/10.17979/ja-cea.2026.47.13873Keywords:
Rehabilitation exoskeleton, Admittance control, Rehabilitation engineering, Biomedical Mechatronics, Networked robotic systems, Human-robot interactionAbstract
Admittance control for rehabilitation exoskeletons is well established in the literature, but typical implementations rely on torque sensors embedded in the device or expensive external load cells. This work presents an alternative architecture: an external ROS 2 node that closes the control loop of the Exo-H3 exoskeleton by reading low-cost force-sensing resistors (FSRs) integrated into the articular straps. The control implements a discretised mass-spring-damper (MSD) model that modulates the joint trajectory according to the user’s effort. The complete chain is described —ergonomic FSR enclosure, modular acquisition electronics, ROS 2 node with real-time parameter tuning interface— and the results of a preliminary experimental validation with a healthy volunteer are presented. The system allows voluntary deviations of up to 73˚ at the knee and 53˚ at the hip, validating the feasibility of the approach for active therapy. Its independence from the exoskeleton’s internal sensing makes the solution
portable to other platforms.
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Copyright (c) 2026 Eugenio Manuel Espuela Domínguez, Pablo Sanchez Fernandez, Juan A. Castano, Juan Carballeira López, Antonio José Ama Espinosa
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