Mechanical Design with Experimental Verification of a Lightweight Exoskeleton Chair

Abstract

In this study, a human-chair model was developed as the basis for a wearable-chair design. A prototype chair, HUST-EC, based on the model was fabricated and evaluated. Employing the optimization under the golden divisional method, an optimized simulation of the operating mode with the lowest chair height was implemented. A novel multi-link support structure has been established with parameters optimized using Matlab software. The stress analysis of the solid models was conducted to ensure the adequate support from the designed chair for the user. Ten subjects participated in the evaluation experiment, who performed both static tasks and dynamic tasks. The experimental results consisted of subjective evaluation and objective evaluation. The experimental data demonstrate that (1) the HUST-EC can effectively reduce the activation level of related muscles at a variety of tasks; (2) the plantar pressure was reduced by 54%–67%; (3) the angle between the upper body and the vertical axis was reduced by 59%–77%; (4) the subjective scores for chair comfortability, portability, and stability were all higher than 7. The results further revealed that the designed chair can reduce the musculoskeletal burden and may improve work efficiency.