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A lumbar-degenerative flat back is a condition caused by a decline in back muscle strength with aging. The symptoms of this condition include severe lower back pain and spinal disorders, which restrict people from performing activities of daily living (ADL). Recently, various wearable robots have been developed to assist the weakened muscles. However, despite their effectiveness, the wearables require either bulky and rigid structures (active wearables) or tend to constrain users’ motion (passive wearables). In addition, the complex biomechanics of the human spine have not been sufficiently investigated during the design process. To address these issues, we propose a human-inspired spine assistive robot with a routed twisted string actuator (RTSA, active element) and a flat-back alleviation mechanism (FAM, passive element). This innovative RTSA conforms to the complex human spine curvature while minimizing friction and assists the ADL with its unique prioritizing characteristics. The human spine-inspired FAM, on the other hand, was designed to prevent spinal disorder injury while performing ADL. The experimental results showed that the proposed system successfully reduced the electromyography signals while performing ADL. Furthermore, the spinal disorder injury during trunk motion could be prevented by reducing the lumbopelvic ratio of the users.

The triboelectric effect utilizes the electric potential of materials to generate an electrical output through electrostatic induction between the two oppositely charged surfaces, which grants them unique self-powered characteristics. By utilizing this effect, self-powered tactile sensors have been studied in the previous researches. However, the conventional triboelectric tactile sensors have drawbacks of limited dynamic range due to the decreasing sensitivity under increased applied pressures. Owing to this disadvantage, the triboelectric tactile sensor has not been extensively employed in smart manufacturing applications where a consistently high sensitivity within the dynamic range is preferred. In order to address this issue, a lightweight, compact, bio-friendly and highly sensitive self-powered triboelectric tactile sensor has been investigated based on the triboelectric effect. By integration of deformable foam layer, triboelectric tactile sensor is able to shift the dynamic range by 76–98 kPa without having to employ gain adjustment circuit board or modifying the properties of the sensor (geometric, materials, etc.). The proposed tactile sensor can be employed in various smart manufacturing applications in which light, self-powered, and high-performance tactile sensors are required to reduce the weight and energy consumption.