Design of a hybrid haptic wearable device for upper limb amputees to recover the missing sensation

• Main Author: Abdullah, Abdullah Ibrahim
• Format: Thesis
• Language: English; English; English
• Published: 2022
• Subjects: T Technology (General)
• Online Access: http://eprints.uthm.edu.my/8246/1/24p%20ABDULLAH%20IBRAHIM%20ABDULLAH.pdf; http://eprints.uthm.edu.my/8246/2/ABDULLAH%20IBRAHIM%20ABDULLAH%20COPYRIGHT%20DECLARATION.pdf; http://eprints.uthm.edu.my/8246/3/ABDULLAH%20IBRAHIM%20ABDULLAH%20WATERMARK.pdf; http://eprints.uthm.edu.my/8246/

A hybrid haptic feedback stimulation system that is capable of sensing surface texture, and temperature, simultaneously, was designed in this work for prosthetic hand to provide a tactile sensation to amputation patients. In addition, the haptic system was developed to enable the prosthetic’s users to implement withdrawal reflexes due to the thermal noxious stimulus in a quick manner, i.e. in a fast and effective technique. The re-sensation is achieved by non-invasively feedback stimulating the skin of the patients’ residual limbs, based on the type and the level of tactile signals provided by the sensory system of the prostheses. Accordingly, a novel hybrid pressure-vibration-temperature feedback stimulation system was design to provide a huge information regarding the prostheses environment to the users without brain confusion or require long pre-training. Evaluations of sensation and response were performed with healthy volunteers to evaluate the ability of the haptic system to stimulate the human nervous system. The results in term of Stimulus Identification Rate (SIR) show that all the volunteers were correctly able to discriminate the sensation of touch, start of touch, end of touch, and grasping objects. While 94%, 96%, 97%, and 95.24% of the entire stimuli were successfully identified by the volunteers during the experiments of slippage, pressure level, surface texture, and temperature, respectively. In addition, the results verified the ability of the haptic system to excite the human brain at the abnormal noxious stimulus and enable the volunteers to perform a quick withdrawal reflex within 0.32 seconds. The test results and the volunteers' responses established evidence that amputees are able to recover their sense of the contact pressure, the surface texture, and the object temperature as well as to perform thermal withdrawal reflexes using the solution developed in this work.