Abstract This paper proposes a new wheel motion generator to track the centroidal motion of one quadruped-on-wheel robot which has the ability to cross various rough terrains with the model based whole-body torque control. The generator is used to track the whole-robot centroidal motion reference. Firstly, the wheel contact model and the whole-body inverse kinematics model are derived using spatial vectors. The wheel motion is extracted out mathematically depending on the base and the legged motions, which serves as the kinematics model. Then the wheel motion generator is developed by combining both the kinematics model and the robot centroidal momentum/dynamics model. The models are decomposed into three components relating to the base motion, the legged motion and the wheel motion. The adaptive wheel motion references are derived in a detailed mathematical way and several algorithms are developed for the model decompositions. Finally, the robot is simulated to be driven on various rough terrains using the operational space control framework mixed with our proposed compatible prioritized impedance controller. The required torque for multiple tasks is generated by the feed-forward and feedback controllers while fulfilling the contact constraints.

中文翻译：

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使用质心动力学的轮式四足动物在崎岖地形上基于滚动的运动

摘要 本文提出了一种新的车轮运动发生器来跟踪一个四足轮上机器人的质心运动，该机器人具有通过基于模型的全身扭矩控制穿越各种崎岖地形的能力。生成器用于跟踪整个机器人的质心运动参考。首先，利用空间向量推导出车轮接触模型和全身逆运动学模型。车轮运动是根据底座和腿运动从数学上提取出来的，用作运动学模型。然后通过结合运动学模型和机器人质心动量/动力学模型开发车轮运动发生器。模型被分解为与基本运动、腿运动和车轮运动相关的三个部分。自适应车轮运动参考以详细的数学方式导出，并为模型分解开发了几种算法。最后，使用操作空间控制框架与我们提出的兼容优先阻抗控制器相结合，模拟机器人在各种崎岖地形上行驶。多个任务所需的扭矩由前馈和反馈控制器生成，同时满足接触约束。