针对星球探测，设计了一种具有高度对称性的六足轮腿机器人。为适应星球表面的复杂环境，该机器人具有不仅在机身水平面内中心对称而且关于机身水平面对称的结构，同时能够通过腿部构型的变化实现两种运动方式：轮行模式和足行模式。机器人的膝关节采用双平行四边形的传动机构，克服了现有足式机器人膝关节平行四边形机构传动的奇异问题，增加了膝关节的转动范围，实现了单腿关于机身水平面的对称运动。设计了一种基于指数坐标在SE （3）空间上规划的自适应步态，机器人可以利用该自适应步态在没有视觉传感器和局部地图的条件下，仅依靠足底力传感器和机身的惯性测量单元，实现自主连续稳定的行走。利用该机器人结构的高度对称性，提出了一种倾倒恢复策略以适应星球探测过程中的需求。以Adams和MATLAB为虚拟的仿真环境，对六足轮腿机器人的运动模式切换、自适应步态及倾倒恢复进行了仿真，验证了可行性。
A wheel-legged hexapod robot with high symmetries is designed for planetary exploration. With a structure both centrosymmetric in the body horizontal plane and symmetric about its body horizontal plane, this robot can realize two modes of locomotion: wheeled mode and legged mode. In the knee joint, a double parallelogram transmission mechanism is used to avoid the singularity of the traditional parallelogram mechanism, enlarging the motion range of the knee joint. Based on the motion planning in the exponential coordinate on SE(3), an adaptive gait is designed for this wheel-legged hexapod robot. Relying on the force sensor on the feet and inertial measurement unit on the body, this robot using this adaptive gait without the visual sensor and the global map can achieve a stable and continuous walk in an unknown environment. Based on the symmetry of the hexapod robot about the body horizontal plane, the motion planning of the recovery from overturning is designed to meet the need for planetary exploration. Simulations are conducted in the Adams and MATLAB environment. The switch of locomotion modes, the adaptive gait, and the stumble recovery of the wheel-legged hexapod robot are achieved in the simulation.
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