History-Aware Planning for Risk-free Autonomous Navigation on Unknown Uneven Terrain

TL;DR

This paper introduces a layered, history-aware planning system enabling autonomous, mapless navigation of robots over unknown uneven terrain, effectively identifying hazards and guiding safe, rapid traversal.

Contribution

It presents a novel layered pipeline combining terrain identification, hazard detection, and history-based exploration for risk-free navigation without prior maps.

Findings

Successfully navigates unknown uneven terrain in simulations and real-world tests.

Effectively identifies hazardous areas and plans safe paths.

Demonstrates improved safety and efficiency in autonomous navigation.

Abstract

It is challenging for the mobile robot to achieve autonomous and mapless navigation in the unknown environment with uneven terrain. In this study, we present a layered and systematic pipeline. At the local level, we maintain a tree structure that is dynamically extended with the navigation. This structure unifies the planning with the terrain identification. Besides, it contributes to explicitly identifying the hazardous areas on uneven terrain. In particular, certain nodes of the tree are consistently kept to form a sparse graph at the global level, which records the history of the exploration. A series of subgoals that can be obtained in the tree and the graph are utilized for leading the navigation. To determine a subgoal, we develop an evaluation method whose input elements can be efficiently obtained on the layered structure. We conduct both simulation and real-world experiments to evaluate the developed method and its key modules. The experimental results demonstrate the effectiveness and efficiency of our method. The robot can travel through the unknown uneven region safely and reach the target rapidly without a preconstructed map.