Design of Tendon-Actuated Robotic Glove Integrated with Optical Fiber Force Myography Sensor

Abstract

People taken by upper limb disorders caused by neurological diseases suffer from grip weakening, which affects their quality of life. Researches on soft wearable robotics and advances in sensor technology emerge as promising alternatives to develop assistive and rehabilitative technologies. However, current systems rely on surface electromyography and complex machine learning classifiers to retrieve the user intentions. In addition, the grasp assistance through electromechanical or fluidic actuators is passive and does not contribute to the rehabilitation of upper-limb muscles. Therefore, this paper presents a robotic glove integrated with a force myography sensor. The glove-like orthosis features tendon-driven actuation through servo motors, working as an assistive device for people with hand disabilities. The detection of user intentions employs an optical fiber force myography sensor, simplifying the operation beyond the usual electromyography approach. Moreover, the proposed system applies functional electrical stimulation to activate the grasp collaboratively with the tendon mechanism, providing motion support and assisting rehabilitation.

Optical fiber force myography sensor for assessing lower limb movements

“…Moreover, experiments proceeded with a single optical fiber transducer instead of multiple force-sensing resistors, suggesting a reliable operation with minimum measurement channels. One anticipates integration with an FES module for rehabilitation purposes, 5 recalling that optical fibers are immune to electromagnetic interference. Despite its merits, decoding complex motions requires additional transducers to discriminate the response of individual lower limb joints and correct ambiguities due to ankle movement or intentional contractions.…”

“…We previously created a robotic glove for hand rehabilitation with fiber transducers coupled to the forearm, combining FMG and functional electrical stimulation (FES). 5 Thus, we extend such developments to assess the knee joint angle and analyze the optical signals acquired for selected actions like walking and jumping, providing valuable insights toward assistive exoskeletons and rehabilitation systems.…”

A Review of EMG-, FMG-, and EIT-Based Biosensors and Relevant Human–Machine Interactivities and Biomedical Applications

“…Most of FMG’s application in the medical field focus on rehabilitation training and disease prediction. Neto et al designed a tendon-actuated robotic glove with an optical fiber force myography sensor [ 47 ]. They propose a system that features tendon-driven actuation through servo motors, which can help users move their fingers according to wishes.…”

“…Combining synchronized EMG and EIT to measure muscle activity [ 114 ]. A disabled assistive robotic glove using optical fiber force myography sensor [ 47 ]. Differential diagnosis of temporomandibular joint disorders using sEMG [ 115 ].…”

A Soft Hand Exoskeleton With a Novel Tendon Layout to Improve Stable Wearing in Grasping Assistance

“…Regarding the actuators, proposed designs of tendon-driven hand exoskeletons place the motors remotely with respect to the hand, through Bowden cables [6], [17], [18], [19], [23]. On one side this choice reduces weight and encumbrance at the hand, on the other side it requires longer Bowden cables, relatively flexible, that compromise the overall wearability of the system and efficiency of the transmission.…”