Embroidered Electrodes for Control of Affordable Myoelectric Prostheses

Abstract

The low-cost manufacturing and maintenance of prostheses is of vital importance to their successful deployment in developing countries. Low-cost prosthesis actuation is generally achieved by combining pre-programmed control strategies, with surface-electromyographic measurements taken from the residual limb. In a standard setting, these signals are measured with disposable gel electrodes. However, this limit on electrode reuse requires that prosthesis users have a stable supply of electrodes. Alternatively, the textile electrodes sewn from conductive thread are studied in the context of hand gesture recognition to consider their future use with low-cost prostheses. In this paper, it is demonstrated that textile electrodes can be applied for gesture recognition. To do so, surface electromyography (sEMG) experiments are run in South Africa on three amputees where they were asked to perform gestures with their phantom limb (i.e., the missing limb segment). A gesture recognition method is implemented, and the classification accuracy with data recorded from textile electrodes is compared to that from gel electrodes. Further analysis examining the relationship between classifier performance and physiological parameters are performed. Results show that textile electrodes can be used to perform accurate gesture recognition, and are comparable to disposable gel electrodes. This demonstrates that low-cost sensory systems are not barrier to myoelectric control in developing countries.

Fabric Vest Socket with Embroidered Electrodes for Control of Myoelectric Prosthesis

“…These methods tend to have limited practicality and are not enough to be adapted to the use of various applications. The previous embroidered electrodes [19][20][21]35] have a flat-type design, whereas the developed electrodes stick more closely to the skin as a three-dimensional loop-type design. The shoulder socket embedding the proposed electrodes not only overcomes these issues but also provides a technology that can be easily applied to the HMI, as well as the prosthetic industry.…”

“…Jiang et al [14] developed a nonwoven fabric sEMG sensor and conducted the artificial neural network to verify the performance of the developed fabric sensor. Embroidered electrodes have been designed for control of myoelectric prostheses by [20,21]. Most of the proposed electrodes were made either using commercial electrodes or without an adhesive property.…”

Capacitivo

“…We designed the electrode pattern using graphics progra) mming software (e.g., Processing) and then saved into an SVG file that was readable by the cutting machine. In comparison to alternative methods like embroidering [26], knitting [13], weaving [27], our approach creates electrodes that are precise in shape and location, while keeping the costs low.…”

Low-Cost Textile Myoelectric Control of Knee-Ankle-Foot-Orthosis

“…Recently, advances in the creation of embroidered electrodes [10] have resulted in a low-cost SEMG sensing system, which can be used to perform motion classification from wearables [26] or predict gestures of phantom-limb with amputees [11]. These electrodes can be made from inexpensive conductive textiles, and provide many advantages over standard gel or metal plate electrodes, such as re-usability and local manufacturing.…”

“…16, and the fact that the electrodes are reusable drives the cost even lower. However, while they have been shown to be effective in applications involving affordable upper-limb prosthetics [11], their use in orthotics is so far untested. In this study, the use of embroidered textile SEMG sensors is investigated with a view to assessing their suitability as the myoelectric interface of a KAFO for control of the knee joint (see Fig.…”