Exoskeleton for ankle joint flexion/extension rehabilitation

  • José Luis Sarmiento Ramos Universidad Manuela Beltrán https://orcid.org/0000-0003-3726-1282
  • Juan Camilo Suárez Galvis Universidad Manuela Beltrán
  • Valentina Grisales Muñoz Universidad Manuela Beltrán
Keywords: Rehabilitation robotics, Wearable robotics, Plantarflexion, Dorsiflexion, Model, Euler-Lagrange, Control, Arduino


This work presents the modelling, design, construction, and control of an exoskeleton for ankle joint flexion/extension rehabilitation. The dynamic model of the ankle flexion/extension is obtained through Euler-Lagrange formulation and is built in Simulink of MATLAB using the non-linear differential equation derived from the dynamic analysis. An angular displacement feedback PID controller, representing the human neuromusculoskeletal control, is implemented in the dynamic model to estimate the joint torque required during ankle movements. Simulations are carried out in the model for the ankle flexion/extension range of motion (ROM), and the results are used to select the most suitable actuators for the exoskeleton. The ankle rehabilitation exoskeleton is designed in SolidWorks CAD software, built through 3D printing in polylactic acid (PLA), powered by two on-board servomotors that deliver together a maximum continuous torque of 22 [kg cm], and controlled by an Arduino board that establishes Bluetooth communication with a mobile app developed in MIT App Inventor for programming the parameters of the rehabilitation therapies. The result of this work is a lightweight ankle exoskeleton, with a total mass of 0.85 [kg] including actuators (servomotors) and electronics (microcontroller and batteries), which can be used in telerehabilitation practices guaranteeing angular displacement tracking errors under 10%.


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Author Biographies

José Luis Sarmiento Ramos, Universidad Manuela Beltrán

Universidad Manuela Beltrán, Bucaramanga, Colombia.

Juan Camilo Suárez Galvis, Universidad Manuela Beltrán

Universidad Manuela Beltrán, Bucaramanga, Colombia.

Valentina Grisales Muñoz, Universidad Manuela Beltrán

Universidad Manuela Beltrán, Bucaramanga, Colombia.


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How to Cite
Sarmiento Ramos, J., Suárez Galvis, J., & Grisales Muñoz, V. (2022). Exoskeleton for ankle joint flexion/extension rehabilitation. ITECKNE, 19(2). https://doi.org/https://doi.org/10.15332/iteckne.v19i2.2773
Accepted for Publication