Continuum robots have attracted increasing attention in recent years due to their intrinsic compliance and safety. Nevertheless, the use of structure compliance may lead to reduction of stiffness and positioning precision. This paper presents a novel design of a hybrid continuum robot whose actuators are composed of pneumatic muscles and embedded elastic rods. Such robot can switch drive modes between large-scale movement and fine adjustment of position by employing a locking mechanism to change its stiffness. A three-dimensional static model of the robot is presented using an improved Kirchhoff rod theory, where elastic deformation of the robot is accounted for from an optimal control point of view via minimal total potential energy principle. Experiments were carried out to validate the static model and to test the stiffness and precision of the robot. This work provides a possible way to strengthen the control precision of a continuum robot with compliant structure.

中文翻译：

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基于内置弹性杆的气动肌肉的混合连续体机器人

近年来，连续体机器人因其固有的合规性和安全性而受到越来越多的关注。然而，使用结构顺应性可能会导致刚度和定位精度的降低。本文提出了一种混合连续体机器人的新颖设计，其执行器由气动肌肉和嵌入式弹性杆组成。这种机器人通过采用锁定机构来改变其刚度，可以在大范围运动和位置微调之间切换驱动模式。使用改进的基尔霍夫杆理论提出了机器人的三维静态模型，其中通过最小总势能原理从最佳控制的角度考虑了机器人的弹性变形。进行了实验以验证静态模型并测试机器人的刚度和精度。这项工作为增强具有柔顺结构的连续体机器人的控制精度提供了一种可能的方法。