A Development of the Novel Wearable Assistive Device

Due to rising retirement ages and declining birth rates, workforce health is increasingly important. Overuse injuries, especially of the upper limbs, are a significant cause of occupational accidents worldwide. Therefore, this study develops a novel wearable assistive device (NWAD) that combines non-invasive surface electromyography (sEMG) with inertial measurement units to enhance upper limb rehabilitation. The NWAD uses both anthropometric and sEMG data to determine optimal sensor placement for measuring the major muscles: the deltoid at 5 cm below the acromion, and the biceps\/triceps at 17 cm below the acromion. In addition, this study recruits 104 participants (44 men, 60 women, ages 25-85), divided into three main experimental stages: upper limb anthropometry, muscle positioning with sEMG, and usability and wearing behavior evaluations. The results show that the NWAD is significantly more effective and user-friendly than traditional devices, particularly for the elderly group (65-85 years), who rate the NWAD highly (78.92, meaning \u201cvery good\u201d) on the System Usability Scale. The middle-aged group (45-64 years) gives only a moderate score, while elderly users are more willing to continue using the novel device. The NWAD also demonstrates a 41.95% reduction in average wear time compared to traditional devices (84.37s vs. 145.33s), with age influencing wear time the most (for example, middle-aged users take the longest). On the other hand, gender differences are not significant, but females perform tasks slightly faster. The NWAD provides a more inclusive and efficient solution for upper limb rehabilitation, but further testing is needed to validate its robustness for laborers.