Knee Exoskeletons Design Approaches to Boost Strength Capability: A Review

Exoesqueleto para incrementar la fuerza en las rodillasThere are different devices to increase the strength capacity of people with walking problems. These devices can be classified into exoskeletons, orthotics, and braces. This review aims to identify the state of the art in the design of these medical devices, based on an analysis of patents and literature. However, there are some difficulties in processing the records due to the lack of filters and standardization in the names, generating discrepancies between the search engines, among others. Concerning the patents, 74 patents were analyzed using search engines such as Google Patents, Derwent, The Lens, Patentscope, and Espacenet over the past ten years. A bibliometric analysis was performed using 63 scientific reports from Web of Science and The Lens in the same period for scientific communications. The results show a trend to use the mechanical design of exoskeletons based on articulated rigid structures and elements that provide force to move the structure. These are generally two types: (a) elastic elements and (b) electromechanical elements. The United States accounts for 32% of the technological patents reviewed. The results suggest that the use of exoskeletons or orthoses customized to the users’ needs will continue to increase over the years due to the worldwide growth in disability, particularly related to mobility difficulties and technologies related to the combined use of springs and actuators

Actuadores de nitinol aplicados en la mimetización del sistema de propulsión de peces con median paired fin

Este artículo presenta una propuesta original para diseñar actuadores empleando una aleación con memoria de forma shape memory alloy conocida corno nitinol. La aplicación se centra en el uso de estos actuadores en un robot que mimetiza a los organismos poseedores de aletas de locomoción tipo median paired fin

Diseño de una prótesis de mano para uso en teclados con interfaz sEMG

"Objetivos: En la actualidad existen diversas opciones de prótesis de mano, sin embargo, ninguna de ellas es adecuada para la utilización de teclados, debido a la lentitud o falta de movimientos adecuados. En este trabajo se plantea una prótesis de mano

Adjustable Stiffness-Based Supination–Pronation Forearm Physical Rehabilitator

This paper reports a new medical device together with a control strategy that focuses on the following tasks: (1) a trajectory tracking problem associated with the supination–pronation motion of the wrist–forearm for purposes of rehabilitation and (2) the adjustment of the system’s stiffness associated with the applied torque guaranteeing the angular motion of the rehabilitator as well as the resistance that potential users must overcome. These two tasks are oriented to regain the range of motion (ROM) of the wrist–forearm and to improve the strength of the associated muscles. It is worth mentioning that this device has not been clinically validated. However, the performance of the closed-loop medical device is validated with preliminary experiments with a healthy subject based on movement patterns involving passive, assisted-resisted, and active phases of rehabilitation protocols

Towards a Non-Contact Method for Identifying Stress Using Remote Photoplethysmography in Academic Environments

Stress has become a common condition and is one of the chief causes of university course disenrollment. Most of the studies and tests on academic stress have been conducted in research labs or controlled environments, but these tests can not be extended to a real academic environment due to their complexity. Academic stress presents different associated symptoms, anxiety being one of the most common. This study focuses on anxiety derived from academic activities. This study aims to validate the following hypothesis: by using a non-contact method based on the use of remote photoplethysmography (rPPG), it is possible to identify academic stress levels with an accuracy greater than or equal to that of previous works which used contact methods. rPPG signals from 56 first-year engineering undergraduate students were recorded during an experimental task. The results show that the rPPG signals combined with students’ demographic data and psychological scales (the State–Trait Anxiety Inventory) improve the accuracy of different classification methods. Moreover, the results demonstrate that the proposed method provides 96% accuracy by using K-nearest neighbors, J48, and random forest classifiers. The performance metrics show better or equal accuracy compared to other contact methods. In general, this study demonstrates that it is possible to implement a low-cost method for identifying academic stress levels in educational environments