Tendon_sheath artificial muscle (TSAM) is a type of artificial muscle, which is widely used in robotic flexible endoscopies. The characteristics of the tendon force/position transmission were studied recently, but the control issue of the TSAM twist is still barely concerned. In this article, an effective robust control scheme is proposed for the TSAM twist, which achieves satisfactory tracking performance. First, a rigorous model was developed for the TSAM twist with consideration of parameters uncertainty and actuator input constraints, moreover, the disturbance of the discontinuous friction (Coulomb friction) was analyzed. Next, by applying some signal operation methods, a nonlinear robust controller was designed. In addition, the stability of the control strategy was proven theoretically by utilizing Lyapunov-based theory. Finally, a series of hardware experiments were conducted on a robotic flexible ureteroscope test-bed. The feasibility of the proposed model, the effectiveness and robustness of the designed control method were extensively validated.

中文翻译：

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子槽底永磁体混合励磁双凸极电机的定量分析及比较研究


腱鞘人工肌肉（TSAM）是人工肌肉的一种，广泛应用于机器人柔性内窥镜中。最近研究了腱力/位置传递的特性，但 TSAM 扭转的控制问题仍然很少被关注。本文针对TSAM扭曲提出了一种有效的鲁棒控制方案，取得了令人满意的跟踪性能。首先，考虑参数不确定性和执行器输入约束，建立了TSAM扭转的严格模型，此外，还分析了不连续摩擦（库仑摩擦）的干扰。接下来，应用一些信号运算方法，设计了非线性鲁棒控制器。此外，利用基于Lyapunov的理论从理论上证明了控制策略的稳定性。最后在机器人输尿管软镜试验台上进行了一系列硬件实验。所提出模型的可行性、所设计控制方法的有效性和鲁棒性得到了广泛验证。