Biomimicry of the stomach's peristaltic contractions can be challenging in the design, modeling, and control of a soft actuator. The mimicking of organ contractions advances our knowledge of the digestive system and analyzes the biological behavior by testing with a physical robot. This article proposes a ring-shaped soft pneumatic actuator (RiSPA) as a segment of the digestive tract. RiSPA is made of a ring frame with embedded bellow actuators that generate contractive motions. An embedded sensory system measures the contraction using range sensors. The kinematics and dynamics of RiSPA's contraction are modeled and simulated, while a state feedback algorithm is applied to them. The simulation results are validated experimentally by comparing the RiSPA measurements with desired applied signals. The proposed actuator provides controllable symmetrical and asymmetrical contractions analog to the human stomach. The results of RiSPA validate the prediction performance of the simulation and controller with applied sinusoidal signals as a peristaltic wave. RiSPA contractions can be applied to a broad range of applications, such as imitating the esophagus and intestine contractions.

中文翻译：

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用于大变形的仿生环形软气动执行器

胃蠕动收缩的仿生学在软致动器的设计、建模和控制中可能具有挑战性。器官收缩的模仿提高了我们对消化系统的了解，并通过使用物理机器人进行测试来分析生物行为。本文提出了一种环形软气动致动器（RiSPA）作为消化道的一部分。RiSPA 由带有嵌入式波纹管致动器的环形框架制成，可产生收缩运动。嵌入式传感系统使用距离传感器测量收缩。对 RiSPA 收缩的运动学和动力学进行建模和模拟，同时对其应用状态反馈算法。通过将 RiSPA 测量值与所需的应用信号进行比较，仿真结果得到了实验验证。所提出的致动器提供类似于人胃的可控对称和不对称收缩。RiSPA 的结果验证了仿真和控制器的预测性能，其中应用正弦信号作为蠕动波。RiSPA 收缩可应用于广泛的应用，例如模仿食道和肠道收缩。