Pleated pneumatic artificial muscles have interesting properties that can be of considerable significance in robotics and automation. With a view to the potential use of pleated pneumatic artificial muscles as actuators for a fatigue test bench (high forces and small displacements), the bandwidth characteristics of a muscle-valve system were investigated. Bandwidth is commonly used for linear systems, as the Bode plot is independent of the amplitude of the input signal. However, due to the non-linear behaviour of pleated pneumatic artificial muscles, the system's gain becomes dependent on the amplitude of the input sine wave. As a result, only one Bode plot is insufficient to clearly describe or identify a non-linear system. In this study, the bandwidth of a muscle-valve system was assessed from two perspectives: a varying amplitude and a varying offset of the input sine wave. A brief introduction to pneumatic artificial muscles is given. The concept of pleated pneumatic artificial muscles is explained. Furthermore, the different test methods and experimental results are presented.

中文翻译：

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褶皱气动人工肌肉的带宽特性研究

褶皱的气动人造肌肉具有有趣的特性，在机器人技术和自动化中可能具有相当重要的意义。鉴于潜在地使用褶皱的气动人造肌肉作为疲劳试验台的执行器（高力和小位移），研究了肌肉-阀门系统的带宽特性。带宽通常用于线性系统，因为波特图与输入信号的幅度无关。但是，由于打褶的气动人造肌肉的非线性行为，系统的增益变得取决于输入正弦波的幅度。结果，仅一个伯德图不足以清楚地描述或识别非线性系统。在这项研究中，从两个角度评估了肌肉-瓣膜系统的带宽：输入正弦波的变化幅度和偏移量。简要介绍了气动人造肌肉。解释了打褶的气动人造肌肉的概念。此外，介绍了不同的测试方法和实验结果。