Despite advances in a diversity of environments, snake robots are still far behind snakes in traversing complex 3-D terrain with large obstacles. This is due to a lack of understanding of how to control 3-D body bending to push against terrain features to generate and control propulsion. Biological studies suggested that generalist snakes use contact force sensing to adjust body bending in real time to do so. However, studying this sensory-modulated force control in snakes is challenging, due to a lack of basic knowledge of how their force sensing organs work. Here, we take a robophysics approach to make progress, starting by developing a snake robot capable of 3-D body bending with contact force sensing to enable systematic locomotion experiments and force measurements. Through two development and testing iterations, we created a 12-segment robot with 36 piezo-resistive sheet sensors distributed on all segments with compliant shells with a sampling frequency of 30 Hz. The robot measured contact forces while traversing a large obstacle using vertical bending with high repeatability, achieving the goal of providing a platform for systematic experiments. Finally, we explored model-based calibration considering the viscoelastic behavior of the piezo-resistive sensor, which will for useful for future studies.
翻译:尽管在各种环境中取得了进步,但蛇体机器人仍然远远落后于蛇体,它们横跨复杂的三维地形,障碍很大。这是因为对如何控制三维身体弯曲以推向地形特征以产生和控制推进力缺乏了解。生物研究表明,一般蛇体使用接触力感应感应来调节身体弯曲,从而实时调整体积。然而,研究蛇体中的这种感官调控力量控制具有挑战性,因为缺乏对其力感应器官如何起作用的基本知识。在这里,我们采取强力物理学方法来取得进展,首先是开发一种蛇体机器人,能够用接触力感测来弯曲三维体,以便能够进行系统的移动实验和武力测量。通过两次开发和测试,我们创建了12层结构机器人,配有36个实时弯曲。所有部分都配有30赫兹的相容贝频率的相容贝性贝壳。机器人测量了接触力,同时使用高垂直弯曲和高重复性垂直弯曲来克服一个大障碍,从而实现提供系统实验平台的目标。最后,我们探索了一个基于模型的校准感官未来行为,将研究如何校准。