A walker assists elderly people with age-related reduced walking ability and helps to improve stability and balance ability. However, if the general-type walker (GTW) is used on an uneven, obstacle, or sloped terrain, it may cause excessive muscle use and falls. Therefore, in this study, we developed a caterpillar-type walker (CTW) that elderly people can safely use in various terrains. Twelve elderly who were able to walk normally participated in the study. The activity of upper and lower extremity muscles, the number of obstacles overcome, and walking speed was compared and analyzed when using two types of walkers in uneven terrain, obstacle terrain, and sloped terrain. In addition, satisfaction with the use of these walkers was evaluated. When CTW was used, the activity of the muscles of the upper and lower extremities was significantly reduced compared to the use of GTW on all terrains. The walker developed in this study overcame obstacles of all heights, but the GTW failed to overcome obstacles starting from the 2 cm section. In terms of walking speed, when the CTW was used, the walking speed was higher than that of the GTW in uneven terrain and obstacle terrain. In satisfaction, there were significant differences in safety, durability, simplicity of use, comfort, and effectiveness. Through these results, it was confirmed that the CTW can efficiently and safely assist the elderly in walking on uneven terrain, obstacle terrain, and inclined terrain.

The decreased muscle mass and increased prevalence of musculoskeletal diseases in the elderly means that this population often experiences difficulty with writing. Although various commercial writing assistive devices exist to reduce pain and improve writing efficiency, low satisfaction with their design prevents them from being widely adopted. In this study, we developed a new ergonomic writing assistive device that overcomes these shortcomings and reduces finger pain. Twenty elderly people with normal writing skills participated in a performance evaluation of our designed device. We used two commercial writing assistive devices and the developed writing assistive device to write a given experimental sentence three times each for each device. For each device, finger-related muscles activity and finger pressure were measured during the experiment, and satisfaction level was evaluated using the modified QUEST 2.0 after the experiment. As a result, the activity in abductor pollicis brevis (18.16%) and first dorsal interosseous muscle (14.17%) was significantly higher when using the NDWAD (newly developed writing assistive device) than when using commercialized WADs (writing assistive devices) (p < 0.05). Finger pressure in the thumb (0.59 N), index finger (1.09 N), and middle finger (0.46 N) was significantly lower when using NDWAD than when using WADs (p < 0.05). The satisfaction level of NDWAD (4.47) was higher than that of WADs. Therefore, we confirmed that our design reduced finger pressure and improved user satisfaction. Consequently, the NDWAD developed in this study can be used as a writing aid not only for the elderly, but also for patients with writing disabilities.