Manzoori Ali Reza, Malatesta Davide, Mortier Alexandre, Garcia Johan, Ijspeert Auke, Bouri Mohamed
Biorobotics Laboratory, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
Institute of Sport Sciences, University of Lausanne (UNIL), CH-1015, Lausanne, Switzerland.
Sci Rep. 2025 Jan 2;15(1):507. doi: 10.1038/s41598-024-84253-y.
Despite their potential, exoskeletons have not reached widespread adoption in daily life, partly due to the challenge of seamlessly adapting assistance across various tasks and environments. Task-specific designs, reliance on complex sensing and extensive data-driven training often limit the practicality of the existing control strategies. To address this challenge, we introduce an adaptive control strategy for hip exoskeletons, emphasizing minimal sensing and ease of implementation. Using only insole pressure and heart rate (HR) sensing, the controller modulates assistance across various locomotor tasks. We evaluated this strategy with twelve able-bodied participants in a real-world scenario including level walking, stairs, and inclines. The controller successfully adapted assistance timing and amplitude to different activities. This resulted in effort intensity reductions (measured by oxygen uptake) of up to 12.6% compared to walking with no exoskeleton, and up to 25.5% compared to walking with the exoskeleton in zero-torque mode. Cardiodynamic response of HR, although delayed, proved sufficient for adaptation in tasks lasting longer than around 45 s, and delay-induced limitations primarily affected brief bouts of abrupt change in intensity. However, we found discernible patterns in HR shortly after the onset of such changes that can be exploited to improve responsiveness. Our findings underscore the potential of HR as a promising measure of user effort intensity, encouraging future research to explore its integration into advanced adaptive algorithms.
尽管外骨骼具有潜在优势，但在日常生活中尚未得到广泛应用，部分原因在于要在各种任务和环境中无缝适配辅助功能面临挑战。特定任务的设计、对复杂传感的依赖以及大量数据驱动的训练常常限制了现有控制策略的实用性。为应对这一挑战，我们推出了一种用于髋部外骨骼的自适应控制策略，强调最少的传感和易于实施。该控制器仅使用鞋垫压力和心率（HR）传感，就能在各种运动任务中调节辅助功能。我们在包括平路行走、上下楼梯和斜坡行走的真实场景中，对12名身体健全的参与者进行了该策略的评估。该控制器成功地根据不同活动调整了辅助的时机和幅度。与不使用外骨骼行走相比，这使得努力强度降低（通过摄氧量衡量）高达12.6%，与外骨骼处于零扭矩模式下行走相比，降低了25.5%。心率的心脏动力学反应虽然有延迟，但在持续时间超过约45秒的任务中，证明足以用于自适应调节，而延迟引起的限制主要影响强度突然变化的短暂发作。然而，我们发现在此类变化开始后不久，心率中存在可识别的模式，可利用这些模式来提高响应能力。我们的研究结果强调了心率作为衡量用户努力强度的一种有前景的指标的潜力，鼓励未来开展研究探索将其集成到先进的自适应算法中。
