In both animals and robots, locomotion capabilities are determined by the physical structure of the system. The majority of legged animals and robots are bilaterally symmetric, which facilitates locomotion with consistent headings and obstacle traversal, but leads to constraints in their turning ability. On the other hand, radially symmetric animals have demonstrated rapid turning abilities enabled by their omni-directional body plans. Radially symmetric tripedal robots are able to turn instantaneously, but are commonly constrained by needing to change direction with every step, resulting in inefficient and less stable locomotion. We address these challenges by introducing a novel design for a tripedal robot that has both frictional and rolling contacts. Additionally, a freely rotating central sphere provides an added contact point so the robot can retain a stable tripod base of support while lifting and pushing with any one of its legs. The SKating, Omni-Oriented, Tripedal Robot (SKOOTR) is more versatile and stable than other existing tripedal robots. It is capable of multiple forward gaits, multiple turning maneuvers, obstacle traversal, and stair climbing. SKOOTR has been designed to facilitate customization for diverse applications: it is fully open-source, is constructed with 3D printed or off-the-shelf parts, and costs approximately $500 USD to build.

翻译：在动物和机器人中，运动能力取决于系统的物理结构。大多数有足动物和机器人具有双侧对称性，这有助于保持恒定方向的运动和跨越障碍，但限制了其转向能力。相比之下，径向对称动物凭借其全向身体结构展现出快速转向能力。径向对称的三足机器人能够实现瞬时转向，但通常受限于每步必须改变方向，导致运动效率低下且稳定性不足。为解决这些挑战，我们提出了一种兼具摩擦接触与滚动接触的新型三足机器人设计。此外，一个自由旋转的中央球体提供了额外接触点，使机器人在抬升或推动任意一条腿时，仍能保持稳定的三足支撑基底。SKOOTR（可滑行全向三足机器人）相比现有其他三足机器人具有更强的通用性和稳定性，能够实现多种前进步态、多种转向动作、障碍跨越及爬楼梯功能。SKOOTR的设计便于针对多样化应用进行定制：其完全开源，采用3D打印或现成零部件制造，制作成本约500美元。