Optical System Based on Multiplexed FBGs to Monitor Hand Movements

Abstract

This contribution reports the development and characterization of an optical system based on parallel Fiber Bragg Gratings (FBGs) to monitor the movements of the wrist and fingers of a hand. The system consisted of a reflective configuration made of FBGs detecting the movements of the fingers and one more located on the wrist as a reference. All FBGs were multiplexed in order to collect the basic movements of the hand. Fibers were embedded in polydimethylsiloxane for protection and to give flexibility to the optical detection setup. Measurements of strain, angle and torsion were performed during the experiments, obtaining sensitivities up to 1.29 pm/µε in strain and 64.23 pm/º in angle. Also, a study on the influence of a single sensor on the performance of the whole system was analyzed for a complete study of this proof of concept. The obtained results present a simple system that can be used to monitor the positions of the hand or for the rehabilitation of patients suffering from neuromotor or post-stroke diseases.

A Review of Wearable Optical Fiber Sensors for Rehabilitation Monitoring

“…Detecting finger joint angles is crucial for assessing an individual’s athletic capacity and health status and is also indispensable in fields such as rehabilitation medicine, physical training, ergonomics, and virtual reality. Sensors can accurately measure joint flexion by monitoring the propagation changes of light within optical fibers, thereby acquiring precise joint angle data [ 85 , 86 , 87 , 88 ]. A key advantage of this technology is its minimal susceptibility to environmental interference and non-irritating nature to the skin, allowing for prolonged wear and real-time monitoring.…”

Automated Forearm Prosthesis Controlling Using Fiber Bragg Grating Sensor

“…The gratings shown a peak reflectivity of about 50 %, a bandwidth of 0.3 nm, and Bragg wavelength resonance of 1532 nm. The strain and angle calibration of the packaged sensor was presented in [28] and are 1.29 pm/µϵ and 64.23 pm/°, respectively.…”

“…This paper is organized as follows. Section II describes the analyses of previous works which gathered the data used in this paper [26] and [28], the data set characteristics regarding the FBG signal, the mechanical design of the prosthesis, hardware components, equations used to control the prosthesis servos, and the developed software architecture to transport the data and control the prosthesis. Section III describes the prosthesis assemble, the materials used to build it, its movements, and a data transmission latency analysis.…”

Study on the Design and Performance of a Glove Based on the FBG Array for Hand Posture Sensing

“…In these studies, selecting the right encapsulation material is fundamental to the gloves' performance. While inflexible materials such as polyimide and polyvinyl chloride [21] have been widely used in previous studies, flexible and malleable materials are better suited to guarantee that the sensors adapt to different joint motions and deformations [22]. The properties of pliable materials entailed greater versatility and comfort, facilitating the integration of the sensor within its application environment to obtain more precise measurements.…”