High-speed legged navigation in discrete and geometrically complex environments is a challenging task because of the high–degree-of-freedom dynamics and long-horizon, nonconvex nature of the optimization problem. In this work, we propose a hierarchical navigation pipeline for legged robots that can traverse such environments at high speed. The proposed pipeline consists of a planner and tracker module. The planner module finds physically feasible foothold plans by sampling-based optimization with fast sequential filtering using heuristics and a neural network. Subsequently, rollouts are performed in a physics simulation to identify the best foothold plan regarding the engineered cost function and to confirm its physical consistency. This hierarchical planning module is computationally efficient and physically accurate at the same time. The tracker aims to accurately step on the target footholds from the planning module. During the training stage, the foothold target distribution is given by a generative model that is trained competitively with the tracker. This process ensures that the tracker is trained in an environment with the desired difficulty. The resulting tracker can overcome terrains that are more difficult than what the previous methods could manage. We demonstrated our approach using Raibo, our in-house dynamic quadruped robot. The results were dynamic and agile motions: Raibo is capable of running on vertical walls, jumping a 1.3-meter gap, running over stepping stones at 4 meters per second, and autonomously navigating on terrains full of 30° ramps, stairs, and boxes of various sizes.

中文翻译：

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四足机器人在复杂和离散地形上的高速控制和导航

由于优化问题具有高自由度动力学和长视距、非凸性，因此在离散和几何复杂的环境中进行高速腿式导航是一项具有挑战性的任务。在这项工作中，我们为可以高速穿越此类环境的腿式机器人提出了一个分层导航管道。建议的管道由 planner 和 tracker 模块组成。规划器模块通过基于采样的优化以及使用启发式和神经网络的快速顺序过滤来查找物理上可行的立足点计划。随后，在物理模拟中执行部署，以确定有关工程成本函数的最佳立足点计划，并确认其物理一致性。这个分层规划模块在计算效率上是有效的，同时在物理上是准确的。跟踪器旨在从规划模块准确踩到目标立足点。在训练阶段，立足点目标分布由生成模型给出，该模型与跟踪器进行竞争性训练。此过程可确保跟踪器在具有所需难度的环境中进行训练。生成的跟踪器可以克服比以前的方法更困难的地形。我们使用内部动态四足机器人 Raibo 演示了我们的方法。结果是动态和敏捷的动作：Raibo 能够在垂直的墙壁上奔跑，跳过 1.3 米的间隙，以每秒 4 米的速度跑过踏脚石，并在充满 30° 坡道、楼梯和各种大小箱子的地形上自主导航。