Caves and lava tubes on the Moon and Mars are sites of geological and astrobiological interest but consist of terrain that is inaccessible with traditional robot locomotion. To support the exploration of these sites, we present ReachBot, a robot that uses extendable booms as appendages to manipulate itself with respect to irregular rock surfaces. The booms terminate in grippers equipped with microspines and provide ReachBot with a large workspace, allowing it to achieve force closure in enclosed spaces, such as the walls of a lava tube. To propel ReachBot, we present a contact-before-motion planner for nongaited legged locomotion that uses internal force control, similar to a multifingered hand, to keep its long, slender booms in tension. Motion planning also depends on finding and executing secure grips on rock features. We used a Monte Carlo simulation to inform gripper design and predict grasp strength and variability. In addition, we used a two-step perception system to identify possible grasp locations. To validate our approach and mechanisms under realistic conditions, we deployed a single ReachBot arm and gripper in a lava tube in the Mojave Desert. The field test confirmed that ReachBot will find many targets for secure grasps with the proposed kinematic design.

中文翻译：

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使用 ReachBot 进行运动操控

月球和火星上的洞穴和熔岩管是具有地质和天体生物学意义的地点，但其地形是传统机器人运动无法到达的。为了支持对这些地点的探索，我们推出了 ReachBot，这是一种机器人，它使用可伸缩的吊杆作为附件，在不规则的岩石表面上操纵自身。吊杆终止于配备微刺的夹具，并为 ReachBot 提供了较大的工作空间，使其能够在封闭空间（例如熔岩管壁）中实现强制闭合。为了推动 ReachBot，我们提出了一种用于非步态腿部运动的运动前接触规划器，它使用类似于多指手的内力控制来保持其细长的吊杆处于紧张状态。运动规划还取决于寻找并执行对岩石特征的安全抓握。我们使用蒙特卡罗模拟来指导夹具设计并预测抓取强度和变化性。此外，我们使用两步感知系统来识别可能的抓取位置。为了在现实条件下验证我们的方法和机制，我们在莫哈韦沙漠的熔岩管中部署了单个 ReachBot 手臂和夹具。现场测试证实，ReachBot 将通过所提出的运动学设计找到许多安全抓取的目标。