Departement of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul, Republic of Korea.
PLoS One. 2022 Aug 4;17(8):e0271764. doi: 10.1371/journal.pone.0271764. eCollection 2022.
Exosuits have been broadly researched owing to their benefits from soft and deformable nature. However, compared to exoskeletons, the exosuits have disadvantages in that the deformation of suit and human tissue can cause dissipation, leading to low force transfer efficiency. In this study, we explore the force capability and human-suit stiffness depending on the anchor point positions of the exosuit, introducing a better understanding of exosuit design. We found the relationships between the anchor point position and the force capability, and the anchor point position and the human-suit stiffness by conducting human subject experiments. When the distance between the anchor point of the waist belt and the anchor point of the thigh brace increased, the force capability increased, whereas the human-suit stiffness decreased. Also, statistical analyses are implemented to verify significant differences according to the anchor point position with a 5% significance level. Moreover, we discuss why the capability of force transmission and the human-suit stiffness differ depending on the anchor point positions. The force capability differed with anchor point positions because of the change in the effective cable stroke. Additionally, the force capability changes nonlinearly owing to the body curve as the condition level of the anchor points changes. The human-suit stiffness is affected by the interference of the body when the assistive force is transmitted through the cable. Characteristics of the force capability and human-suit stiffness model can be used to optimize the performance of existing exosuit or to serve a valuable guide of design a new exosuit when the exosuit needs to maximize the force capability or stiffness.
外骨骼由于其柔软和可变形的特性而得到了广泛的研究。然而，与外骨骼相比，外骨骼在变形方面存在劣势，因为套装和人体组织的变形会导致能量耗散，从而导致力传递效率低下。在这项研究中，我们探索了外骨骼的力能力和人与套装的僵硬程度取决于套装的固定点位置，从而更好地了解外骨骼的设计。我们通过人体实验发现了固定点位置与力能力之间的关系，以及固定点位置与人与套装的僵硬程度之间的关系。当腰带上的固定点和大腿支架上的固定点之间的距离增加时，力能力增加，而人与套装的僵硬程度降低。此外，还进行了统计分析，以验证在 5%的显著水平下根据固定点位置的显著差异。此外，我们讨论了为什么力传递能力和人与套装的僵硬程度会因固定点位置的不同而不同。力能力因有效电缆行程的变化而不同。此外，由于条件水平的变化，力能力会发生非线性变化。当通过电缆传递辅助力时，人体会干扰套装，从而影响套装的僵硬程度。力能力和人与套装的僵硬程度模型的特点可以用于优化现有外骨骼的性能，或者在需要最大化力能力或僵硬程度时，为设计新的外骨骼提供有价值的指导。
