Zhang Jing, Zhu Aibin, Song Jiyuan, Bao Bingsheng, Su Yuxiang, Xu Peng, Zheng Chunli, Shi Lei, Zhang Xiaodong, Li Xiao
IEEE Trans Biomed Eng. 2025 Feb;72(2):528-539. doi: 10.1109/TBME.2024.3461880. Epub 2025 Jan 21.
This paper aims to enhance exoskeleton compliance during locomotion assistance by reducing misalignment and to improve energy efficiency by overcoming the limitations posed by the bulky structure of powered rigid exoskeletons.
A novel compliant knee exoskeleton, featuring a parallel elastic self-alignment mechanism, has been developed and structurally optimized. The exoskeleton uses adaptive oscillators to determine the wearer's gait phase and provides real-time assistance to the knee joint.
Bench tests demonstrate that the parallel elastic mechanism significantly reduces the driving torque of the knee exoskeleton. Performance evaluations reveal that, compared to a commercial orthosis, the root-mean-square of knee angle error, joint misalignment, and unexpected interaction forces are reduced by 16.5 11.3%, 23.3 4.9%, and 17.7 1.3%, respectively. Gait intervention experiments show reductions in average and maximum muscle activity of the knee joint by 7.6 4.9% and 23.2 5.7%, respectively. Additionally, the exoskeleton decreases negative work performed by the knee joint and the total lower limb by 22.7% and 8.6%, respectively.
The parallel elastic self-alignment mechanism effectively mitigates joint misalignment, while the parallel springs offer partial gravity compensation, thereby enhancing both the energy efficiency and locomotion assistance of the exoskeleton.
The parallel elastic self-alignment mechanism effectively addresses both misalignment and energy efficiency challenges in powered exoskeletons, providing valuable insights for future design improvements.
本文旨在通过减少错位来提高外骨骼在运动辅助过程中的柔顺性，并通过克服动力刚性外骨骼庞大结构所带来的限制来提高能源效率。
研发了一种具有平行弹性自对准机制的新型柔顺膝关节外骨骼，并对其结构进行了优化。该外骨骼使用自适应振荡器来确定穿戴者的步态阶段，并为膝关节提供实时辅助。
台架试验表明，平行弹性机制显著降低了膝关节外骨骼的驱动扭矩。性能评估显示，与商业矫形器相比，膝关节角度误差、关节错位和意外相互作用力的均方根分别降低了16.5±11.3%、23.3±4.9%和17.7±1.3%。步态干预实验表明，膝关节的平均和最大肌肉活动分别减少了7.6±4.9%和23.2±5.7%。此外，外骨骼使膝关节和整个下肢所做的负功分别减少了22.7%和8.6%。
平行弹性自对准机制有效减轻了关节错位，而平行弹簧提供了部分重力补偿，从而提高了外骨骼的能源效率和运动辅助能力。
平行弹性自对准机制有效解决了动力外骨骼中的错位和能源效率挑战，为未来的设计改进提供了有价值的见解。
