| Autor: |
Cholico FA; Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca 46600, Jalisco, Mexico., Paz JA; Centro Universitario de la Ciénega, Universidad de Guadalajara, Avenida Universidad 1115, Ocotlan 47810, Jalisco, Mexico., López Z; Centro Universitario de la Ciénega, Universidad de Guadalajara, Avenida Universidad 1115, Ocotlan 47810, Jalisco, Mexico., Hernández Sámano A; Centro Universitario de la Ciénega, Universidad de Guadalajara, Avenida Universidad 1115, Ocotlan 47810, Jalisco, Mexico., Mena-Barboza E; Centro Universitario de la Ciénega, Universidad de Guadalajara, Avenida Universidad 1115, Ocotlan 47810, Jalisco, Mexico., Bernal-Alvarado J; Departamento de Ingeniería Física, División de Ciencias e Ingenierías Campus Leon, Universidad de Guanajuato, Loma del Bosque 103, Lomas del Campestre, Leon 37150, Guanajuato, Mexico., Velasquez C; Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca 46600, Jalisco, Mexico., Hernández-Gutiérrez R; Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco A.C., Av. Normalistas 800, Guadalajara 44270, Jalisco, Mexico., Quintero LH; Centro Universitario de Ciencias Económico Administrativas, Universidad de Guadalajara, Periférico Norte 799, Col. Los Belenes, Zapopan 45100, Jalisco, Mexico., Cano ME; Centro Universitario de la Ciénega, Universidad de Guadalajara, Avenida Universidad 1115, Ocotlan 47810, Jalisco, Mexico. |
| Abstrakt: |
Objectives : The objective of this paper is to introduce a method to measure the force or pressure over the carpal tunnel indirectly, using a new device to drive the pointer of a computer system. The measurements were compared with those obtained using an ergonomic mouse. Simultaneously, measurements of muscular stress on the digitorum extensor muscle were performed to correlate the applied force against muscle activity. Methods : An experimental setup was constructed using an infrared static receiver plus two wearable moving light emitters, which can be displaced inside a rectangular projected region. The pointer functions are performed through two finger gestures, while the hand is naturally extended. A microcontroller was used to communicate with the computer, which works as a human interface device and possesses firmware to associate the position of each light source with the pointer functions. Meanwhile, force and electromyography sensing circuits were developed to transmit and measure carpal tunnel strength and muscular stress. The system was tested on five healthy volunteers, who were encouraged to solve the same computational tasks using this new device and a trademark ergonomic mouse. Results : Our results show great differences (greater than one magnitude) between the efforts of the same volunteers performing the same predefined tasks using both pointer controllers. Only when the new device was used did the Pearson's correlation coefficients show a higher correlation between the effort measured on the carpal tunnel and the muscular activity. Conclusions : The optic pointer driver diminishes the strength on the carpal tunnel, causing slightly increased stress on the digitorum extensor muscle. |
