Wheeled bipedal robots have garnered increasing attention in exploration and inspection. However, most research simplifies calculations by ignoring leg dynamics, thereby restricting the robot's full motion potential. Additionally, robots face challenges when traversing uneven terrain. To address the aforementioned issue, we develop a complete dynamics model and design a whole-body control framework with terrain estimation for a novel 6 degrees of freedom wheeled bipedal robot. This model incorporates the closed-loop dynamics of the robot and a ground contact model based on the estimated ground normal vector. We use a LiDAR inertial odometry framework and improved Principal Component Analysis for terrain estimation. Task controllers, including PD control law and LQR, are employed for pose control and centroidal dynamics-based balance control, respectively. Furthermore, a hierarchical optimization approach is used to solve the whole-body control problem. We validate the performance of the terrain estimation algorithm and demonstrate the algorithm's robustness and ability to traverse uneven terrain through both simulation and real-world experiments.

翻译：轮式双足机器人在探索与巡检领域日益受到关注。然而，现有研究大多通过忽略腿部动力学来简化计算，从而限制了机器人的完整运动潜力。此外，机器人在不平坦地形上移动时面临挑战。为解决上述问题，我们针对一种新型六自由度轮式双足机器人建立了完整的动力学模型，并设计了包含地形估计的全身控制框架。该模型整合了机器人的闭环动力学以及基于估计地面法向量的地面接触模型。我们采用激光雷达惯性里程计框架和改进的主成分分析进行地形估计。任务控制器（包括PD控制律和LQR）分别用于姿态控制和基于质心动学的平衡控制。此外，通过分层优化方法求解全身控制问题。我们通过仿真和实际实验验证了地形估计算法的性能，并证明了该算法在不平坦地形穿越中的鲁棒性和有效性。