不确定性扰动下双足机器人动态步行的自适应鲁棒控制

针对不确定性扰动下双足机器人动态步行的鲁棒控制问题，建立不确定性扰动下双足机器人的动力学模型. 将特定庞卡莱映射方法拓展到不确定性扰动下双足机器人的稳定性分析，将机器人随机系统的稳定性分析转化为确定性周期系统的稳定性分析. 基于滑模控制方法，提出自适应滑模控制器. 与以往滑模控制器相比，该控制器无需外部扰动的准确幅值信息. 考虑到双足机器人在实际应用中常会遭遇非平整路面，进一步将该自适应滑模控制器拓展到非平整路面的鲁棒控制：提出碰撞速度不变性条件，基于落地速度控制进行在线轨迹规划，基于自适应滑模控制器对机器人进行反馈控制. 基于三维（3-D）五杆双足机器人进行仿真实验，结果表明，所设计的控制器能有效实现机器人在不确定性扰动下的鲁棒控制.

Adaptive robust control of dynamic walking of bipedal robots under uncertain disturbances

A dynamic model for the bipedal robots under uncertain disturbances was established, aiming at the robust control problem of dynamic bipedal walking under uncertain disturbances. The specific Poincaré mapping method was extended to the stability analysis of bipedal robots under uncertain disturbances, by which the stability analysis of a robot random system was transformed into that of a deterministic and periodic system. An adaptive sliding-mode controller was proposed based on the sliding-mode control method. Compared with the traditional sliding-mode controllers, the proposed controller is applicable even when the magnitude information of the external disturbances is not accurately estimated. Considering that bipedal robots often encounter uneven terrains, the proposed sliding-mode controller was further extended to the robust control of dynamic walking on uneven terrains. For this goal, an invariance condition for impact velocity was presented and the trajectories were planned online based on landing-velocity control. Then, the presented controller was used to enforce feedback control on the robot. Numerical simulations were performed on a three-dimensional (3-D) five-link bipedal robot, and results show that the robust control of dynamic bipedal walking subject to uncertain disturbances can be realized by the proposed controller effectively.