Wheel-legged robots combine the advantages of both wheeled robots and legged robots, offering versatile locomotion capabilities with excellent stability on challenging terrains and high efficiency on flat surfaces. However, existing wheel-legged robots typically have limited hip joint mobility compared to humans, while hip joint plays a crucial role in locomotion. In this paper, we introduce Whleaper, a novel 10-degree-of-freedom (DOF) bipedal wheeled robot, with 3 DOFs at the hip of each leg. Its humanoid joint design enables adaptable motion in complex scenarios, ensuring stability and flexibility. This paper introduces the details of Whleaper, with a focus on innovative mechanical design, control algorithms and system implementation. Firstly, stability stems from the increased DOFs at the hip, which expand the range of possible postures and improve the robot's foot-ground contact. Secondly, the extra DOFs also augment its mobility. During walking or sliding, more complex movements can be adopted to execute obstacle avoidance tasks. Thirdly, we utilize two control algorithms to implement multimodal motion for walking and sliding. By controlling specific DOFs of the robot, we conducted a series of simulations and practical experiments, demonstrating that a high-DOF hip joint design can effectively enhance the stability and flexibility of wheel-legged robots. Whleaper shows its capability to perform actions such as squatting, obstacle avoidance sliding, and rapid turning in real-world scenarios.

翻译：轮腿式机器人结合了轮式机器人和腿式机器人的优势，在复杂地形上具有优异的稳定性，在平坦表面上具有高效的运动能力。然而，现有的轮腿式机器人通常髋关节活动度有限，而髋关节在运动中起着至关重要的作用。本文介绍了Whleaper，一种新颖的10自由度双足轮式机器人，每条腿的髋部具有3个自由度。其类人关节设计使其能够在复杂场景中实现适应性运动，确保稳定性和灵活性。本文详细介绍了Whleaper，重点阐述了其创新的机械设计、控制算法和系统实现。首先，髋部自由度的增加带来了稳定性，扩大了可能的姿态范围并改善了机器人的足地接触。其次，额外的自由度也增强了其机动性。在行走或滑行过程中，可以采用更复杂的运动来执行避障任务。第三，我们利用两种控制算法实现了行走和滑行的多模态运动。通过控制机器人的特定自由度，我们进行了一系列仿真和实际实验，证明高自由度髋关节设计能有效提升轮腿式机器人的稳定性和灵活性。Whleaper在实际场景中展示了执行下蹲、避障滑行和快速转向等动作的能力。