Diseño mecánico de un equipo para rehabilitación física de tobillo, por medio de un sistema de motores eléctricos y plataforma móvil.

Abstract

This technological proposal deals with carrying out the mechanical design with CAD and CAE tools of an equipment for the physical ankle rehabilitation and balance training through two mobile platforms activated by servomotors, fitted, in turn, in a support and assistance structure. The equipment performs three movements, dorsal flexion, sole inversion, eversion and adduction abduction. For this proposal development, the state of the art was the first stage. The corresponding interviews to a physiatrist and physiotherapeutic were carried out to obtain the client needs. With the methodologies od conceptual design stressing the quality design QFD the equipment specifications were obtained Three design alternatives were formulated from which the best solution was obtained. With the consolidated conceptual design of the machine the detail design was performed. The equipment CAD modelling with the SolidWorks as well as the kinetics simulations in ADAMS were carried out on the basis of the following parameters, when the most extreme cycle is executed which will be a combination of such movements, going to the maximum ranges of mobility and the maximum rehabilitation speed with which the most critical loads generated in the mechanical elements were obtained. With these loads, the analytic design by resistance and rigidity of each element was carried out. The analytically obtained result were validated applying the method of finite elements with ANSYS. In the process of analysis of the model, the most critical mechanical element was the axis of FD-FP, when verifying its behavior in ANSYS, a maximum equivalent effort of Von Misses was obtained of 478.07 MPa, which was the highest effort in all the mechanical elements, with a safety factor of 1.61, as a consequence of the compact design of the shaft and its geometry. This equipment has the 3 degrees of freedom (GDL) and with the maximum ranges of mobility that the ankle joint has, FP / FD = 50/30 °, IN / EV = 30/20 ° and AD AB = 26/36 °. The maximum weight of the user is 130 kgf, the equipment for physical ankle rehabilitation will have an additional function, balance training for patients with neuronal diseases, through two mobile platforms, in turn housed in a support structure.