Task space trajectory tracking for quadruped robots plays a crucial role on achieving dexterous maneuvers in unstructured environments. To fulfill the control objective, the robot should apply forces through the contact of the legs with the supporting surface, while maintaining its stability and controllability. In order to ensure the operation of the robot under these conditions, one has to account for the possibility of unstable contact of the legs that arises when the robot operates on partially or globally slippery terrains. In this work, we propose an adaptive trajectory tracking controller for quadruped robots, which involves two prioritized layers of adaptation for avoiding possible slippage of one or multiple legs. The adaptive framework is evaluated through simulations and validated through experiments.

翻译：四足机器人在非结构化环境中实现灵巧操作时，任务空间轨迹跟踪起着关键作用。为达成控制目标，机器人需通过腿部与支撑面的接触施加力，同时保持自身稳定性与可控性。为确保机器人在这些条件下运行，必须考虑当机器人在局部或全局滑溜地形上工作时可能出现的腿部不稳定接触问题。本文提出一种四足机器人自适应轨迹跟踪控制器，该控制器采用两个优先级分层的自适应机制，以避免单条或多条腿可能发生的打滑。该自适应框架通过仿真评估并通过实验验证。