Soft continuum robots are getting more popular in areas such as minimally invasive surgery, search and rescue, and inspection due to their inherent compliance and flexibility. However, most of the conventional continuum robots still lack the ability to significantly change size and length. Growth as a means of robotic locomotion is a novel actuation method that can be used to overcome this disadvantage. In this study, we introduce a growing pneumatic soft robot made up of pressurized thin-walled tubings that can move in three-dimensional space with an extension ratio only limited by manufacturing capabilities. Besides the ability to grow from the tip, this design provides active steering by controlling the speed of each tubing separately, controllable stiffness that can be changed during motion, and capability to carry a tool channel. We present models to estimate tip force and position and experimentally verify the force model and robot kinematics. Open-loop speed controller has an overall root mean square error of 2.69% for speeds between 20 and 300 mm/s. The position controller based on the kinematic model has a mean positioning error of 13.9 mm at 100 mm and 22.6 mm at 200 mm longitudinal distance. Robot can produce a tip force of 20.1 N at 150 kPa tubing pressure and reach a maximum speed of 1490 mm/s at 100 kPa. We also demonstrate the navigation capabilities of the robot both in open field and in constrained environments.

中文翻译：

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成长型气动软机器人的设计与开发。

软连续体机器人由于其固有的顺应性和灵活性，在微创手术、搜救、检查等领域越来越受欢迎。然而，大多数传统的连续体机器人仍然缺乏显着改变尺寸和长度的能力。作为机器人运动的一种手段，生长是一种新的驱动方法，可用于克服这一缺点。在这项研究中，我们介绍了一种不断增长的气动软机器人，它由加压薄壁管组成，可以在三维空间中移动，其延伸比仅受制造能力的限制。除了能够从尖端生长外，这种设计还通过分别控制每个油管的速度、可在运动过程中改变的可控刚度以及携带工具通道的能力来提供主动转向。我们提出模型来估计尖端力和位置，并通过实验验证力模型和机器人运动学。对于 20 到 300 mm/s 的速度，开环速度控制器的总体均方根误差为 2.69%。基于运动学模型的位置控制器的平均定位误差在 100 mm 处为 13.9 mm，在 200 mm 纵向距离处为 22.6 mm。机器人可以在 150 kPa 油管压力下产生 20.1 N 的尖端力，并在 100 kPa 下达到 1490 mm/s 的最大速度。我们还展示了机器人在开阔场地和受限环境中的导航能力。基于运动学模型的位置控制器的平均定位误差在 100 mm 处为 13.9 mm，在 200 mm 纵向距离处为 22.6 mm。机器人可以在 150 kPa 油管压力下产生 20.1 N 的尖端力，并在 100 kPa 下达到 1490 mm/s 的最大速度。我们还展示了机器人在开阔场地和受限环境中的导航能力。基于运动学模型的位置控制器的平均定位误差在 100 mm 处为 13.9 mm，在 200 mm 纵向距离处为 22.6 mm。机器人可以在 150 kPa 油管压力下产生 20.1 N 的尖端力，并在 100 kPa 下达到 1490 mm/s 的最大速度。我们还展示了机器人在开阔场地和受限环境中的导航能力。