Development and assessment of a knitted shape memory alloy-based multifunctional elbow brace

Osteoarthritis is a chronic disease that affects joint cartilage and can cause severe pain and disability. Minor neglected injuries may also result in other diseases that affect daily life. Various attempts have been made to develop wearable auxiliary devices using functional fabrics, but few have simultaneously provided both heat and pressure. Using knitted shape memory alloy (SMA) fabric, a module was manufactured that achieved bending and contraction during operation. An elbow brace that simultaneously provided heat and pressure was developed using this module. Subjective evaluation and measurements of the range of motion (ROM), changes in skin temperature (T_sk), clothing pressure (P_c), and blood flow (F_b) were conducted on the elbow brace while being worn by 10 participants. The multifunctional elbow brace (MFEB) developed in this study generated pressure and heat that increased T_sk and P_c, ultimately increasing F_b. In addition, the ROM of the elbow joint was increased after actuating the elbow brace. Subjective evaluation of the heat and pressure sensation demonstrated its applicability to the human body. We confirmed that the elbow brace had a positive effect on F_b and increased the ROM of the joint. These results show the applicability of smart textiles to the development of various wearable devices.