This article presents a methodology for the design of rehabilitation devices that considers factors involved in a clinical environment. This methodology integrates different disciplines that work together. The methodology is composed by three phases and 13 stages with specific tasks, the first phase includes the clinical context considering the requirements of the patient and therapist during the rehabilitation, the second phase is focused in engineering based on the philosophy of digital twin, and in the third phase is evaluated the device. This article explains the characteristics of the methodology and how it was applied in the design of an exoskeleton for passive rehabilitation of upper limb.

RESUMENEn este artículo se presenta un enfoque para rehabilitación pasiva de miembro superior mediante la formulación de cuatro casos de estudio haciendo un análisis de las patologías y los ejercicios que se aplican. Para llevar a cabo la experimentación en los casos propuestos se registraron los datos de las trayectorias de las articulaciones del brazo de un paciente realizando los ejercicios de rehabilitación con un terapeuta. Se diseñó el exoesqueleto ERMIS de siete grados de libertad para emular los movimientos anatómicos en el brazo durante la rehabilitación a partir de los requerimientos de los casos de estudio. Para validar el funcionamiento del exoesqueleto en los casos se simuló el modelo dinámico del ERMIS y se compararon los datos con los datos muestreados de los ejercicios. Al final se presentan los resultados obtenidos de los ejercicios realizados con el exoesqueleto, obteniendo en la precisión un desempeño promedio del 95% en los movimientos de hombro, codo y muñeca al emular la terapia con timón.

Many exoskeletons in scientific communications and patents only reach a technology readiness level corresponding to an experimental physical model (EPM) or a low-fidelity prototype. While only operational in a laboratory environment, the increasing technology readiness level (TRL) in exoskeletons is not widely studied. This work presents a study to reach this aim based on a new methodology that includes two phases, eleven steps, and four case studies from EPM (TRL3) of ERMIS up to TRL 5 of ERMIS. The results of this article show the increase in TRL based on the analysis of the operational parameters of the ERMIS exoskeleton. The validation of the passive rehabilitation movements was made by characterizing the points of their trajectories assisted by an anthropomorphic mechanism used to measure the end-effector position of ERMIS by means of the acquisition of data, obtaining an error of 20 mm. In conclusion, the real performance parameters are detailed, explaining their causes according to the behavior of the exoskeleton in a real environment operating the four case studies. It presents the group of parameters that reach the TRL 5, which were validated in Computer-Aided Design (CAD) software.

The experimental results of forces and efforts derived from the opening of incisions in the orbital cavity in a pig’s head are presented in this article. The different areas of the incision openings are related to the needs at the incision procedure for a dacryocystorhinostomy. In terms of the experimental procedure, an origin and a plane are defined so as to allow the location of the opening of the incision. The incisions are retracted along an axis of said origin. This procedure has been based on the mathematical model developed for this work, which consists of a procedure for determining the behavior of an incision when a force is applied to retract the skin. The experimental data obtained, suggests the existence of an almost linear relationship between the increment of resistance in relation to the time obtained for each opening, the same of which is deemed to be consistent with the behavior of an elastic material.

It is presented the design specifications for a Retractor Robotic System (RRS) based on the surgical necessities in the incisions procedure for a dacryocystorhinostomy. The specifications are conformed by a mathematical model, the experimental data measured, a modular flexible architecture, energy supplier system, the mechanical group, and the safety system. The specifications suggest that the use of flexible polymeric materials for the RRS provide a mayor adaptability of the system with the biological tissue; so a pneumatic actuator could be a suitable option.