This paper presents the design of a 3-DOF prosthetic wrist for transradial myoelectric upper limb prosthesis that allows the orientation of a prosthetic hand to reduce compensatory movements that cause musculoskeletal problems mainly in the back and shoulder. The device is capable of perform passively abduction-adduction movements and actively flexion-extension and pronation-supination movements. The system has a DC motor that transmits power to the active movements and a solenoid for the choice of the type of movement to be performed. In order to validate the design of the components of the device, calculations and simulations were carried out by finite elements method to determine deformations, mechanical resistance and fatigue to define the critical components and maintenance periods. © 2019 IEEE.

Partial hand and transradial amputations are among the most common levels of amputation. In the former case, a mechanical prosthesis is prescribed, while in the latter case either a mechanical or a myoelectric one are used depending on the patient’s preference and access to the technology. While a variety of prostheses designs are aimed to transradial amputees and plenty others are for partial hand amputations, like the 3D-printed open-source concepts that are activated by the user’s wrist, for a faster and more efficient treatment of hand amputations, one design should be adaptive for different levels of amputation without compromising the prosthesis performance. This work describes a powered prosthesis design with modular fingers and space constraints that allow it to be adapted to different levels of amputation. The prosthesis finger lengths could also be customized to user-specif...

This paper presents the development and validation of a tridimensional 7-DOF human body model for the representation and study of closed kinetic chain exercises (CKCE) performed with the feet fixed in space, i.e. low posture exercises. The biomechanical model, a link-segment model, is based on an Euler-Lagrange formulation and employs a generalized joint coordinate system. A top-down mechanical analysis provides an estimation of the internal joint moments, along with the vertical ground reaction forces, using kinematical data collected by inertial sensors. The model is validated by correlating estimated ground reaction forces to kinetic experimental data from force plates. Pearson correlation coefficients were calculated for four CKCE types (150 trials in total). In all cases, a median correlation r > 0.90 was found, hence proving that the proposed model is quite satisfactory for CKCE mo...