Pneumatic soft actuators (PSAs) are components that produce predesigned motion or force in different end-use devices. PSAs are lightweight, flexible, and compatible in human–machine interaction. The use of PSAs in compression therapy has proven promising in proactive pressure delivery with a wide range of dosages for treatment of chronic venous insufficiency and lymphedema. However, effective design and control of PSAs for dynamic pressure delivery have not been fully elaborated. The purpose of this study is to explore interactive working mechanisms between a PSA and lower limbs through establishing fluid–structure coupling models, an intermittent pneumatic compression (IPC) testing system, and conducting experimental validation. The developed IPC testing system consisted of a PSA unit (multichambered bladders laminated with an external textile shell), a pneumatic controller, and various real-time pressure monitoring sensors and accessory elements. The established coupling model characterized the dynamic response process with varying design parameters of the PSA unit, and demonstrated that the design of initial thickness, stiffness, and air mass flow of the PSA, as well as stiffness of limb tissues of the users, influenced PSA-lower limb interactions and resultant pressure dosages. The simulated results presented a favorable agreement with the experimental data collected by the IPC testing system. This study enhanced understanding of PSA-lower limb interactive working mechanisms and provided an evidence-based technical guidance for functional design of PSA. These results contribute to improving the efficacy of dynamic compression therapy for promotion of venous hemodynamics and user compliance in practice.

中文翻译：

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气动软执行器与下肢相互作用的流固耦合模型和实验验证。

气动软执行器 (PSA) 是在不同的最终用途设备中产生预先设计的运动或力的组件。PSA 在人机交互方面是轻量级、灵活和兼容的。事实证明，在加压疗法中使用 PSA 在以广泛剂量的主动压力输送治疗慢性静脉功能不全和淋巴水肿方面很有前景。然而，用于动态压力输送的 PSA 的有效设计和控制尚未得到充分阐述。本研究的目的是通过建立流固耦合模型、间歇气动压缩（IPC）测试系统和进行实验验证，探索PSA与下肢之间的交互工作机制。开发的 IPC 测试系统包括一个 PSA 单元（与外部纺织外壳层压的多腔气囊）、一个气动控制器以及各种实时压力监测传感器和附件元件。建立的耦合模型表征了PSA单元不同设计参数下的动态响应过程，证明了PSA的初始厚度、刚度和空气质量流量的设计以及用户肢体组织的刚度对PSA的影响- 下肢相互作用和由此产生的压力剂量。模拟结果与 IPC 测试系统收集的实验数据具有良好的一致性。本研究加深了对PSA-下肢交互工作机制的理解，为PSA的功能设计提供了循证技术指导。