Applications of sensory feedback in motorized upper extremity prosthesis: a review

Abstract

Dexterous hand movement is possible due to closed loop control dependent on efferent motor output and afferent sensory feedback. This control strategy is significantly altered in those with upper limb amputation as sensations of touch and movement are inherently lost. For upper limb prosthetic users, the absence of sensory feedback impedes efficient use of the prosthesis and is highlighted as a major factor contributing to user rejection of myoelectric prostheses. Numerous sensory feedback systems have been proposed in literature to address this gap in prosthetic control; however, these systems have yet to be implemented for long term use. Methodologies for communicating prosthetic grasp and touch information are reviewed, including discussion of selected designs and test results. With a focus on clinical and translational challenges, this review highlights and compares techniques employed to provide amputees with sensory feedback. Additionally, promising future directions are discussed and highlighted.

Optimizing User Integration for Individualized Rehabilitation

“…The device may also provide information to the user about the plant that the user does not otherwise have. In this case, the device may restore sensory feedback (touch or movement) to the user about bodyenvironment-task interactions [31,32]. The device may do so through neural activation to restore basic sensory capabilities such as vision, hearing, touch, or kinesthesia [33].…”

“…And tactile manipulation of skin at these sites stimulates aferent pathways that elicit sensory feedback of the missing hand to the amputee. The biological neural-machine-interface created by TMR is a unique platform for investigating control of multi-sensory prosthesis [7,31,32] and potential cognitive frameworks of agency. Speciically, agency considerations may enhance the EMG motor command interface and augment how sensory feedback is perceived by the user.…”

Introductory Chapter: Toward Near-Natural Assistive Devices

“…It is believed that the implementation of feedback to create a closed-loop system will improve the performance of the prosthetic. In active prosthetics, three of the major ways to provide sensor feedback to the user include substitution, modality-matched, and somatically matched feedback mechanisms [35]. In general, substitution feedback is the application of an indirect stimulus that is intended to substitute another form of stimulus, i.e., substituting a touch stimulus with an auditory one.…”

“…Somatotopically matched feedback causes the user to perceive the correct sensation from the correct location, as if the prosthetic was their natural limb. In order to create a prosthetic that most accurately performs sensory feedback, both modality-matched and somatotopically matched feedbacks should be employed [2,35].…”

“…At a distance of approximately 1 meter, the conduction times of afferent nerves range between approximately 14 and 28 ms [25]; therefore a short latency of the additional feedback is important to create real-time reactions. Short latencies, similar to that of a normal human hand, are also believed to help promote user ownership of the prosthetic [35].…”