Opinion

Topological Map-Based RRT Improves Mobile Robot Autonomous Exploration Efficiency

Archive editionRyan OkaforMay 9, 2023· 6,381 views

Researchers propose TMRRT algorithm combining topological maps with RRT to reduce repeated exploration, cutting exploration time by up to 15.7% and path length by 34.3%.

In context

In 2023, autonomous exploration remained a bottleneck for mobile robots in industrial and service applications. Traditional SLAM required manual control for map building, which was inefficient and impractical in inaccessible areas. Researchers at Fudan University addressed this by enhancing frontier-based exploration with topological memory to reduce redundant revisits.

What was reported

The team proposed TMRRT (topological map based rapidly exploring random tree), which integrates variable-growth-rate local and global RRTs for frontier detection, Mean Shift clustering to reduce frontier data, and a topological map that stores historical best exploration points. This map guides the robot to avoid previously explored regions, reducing loop-closure inefficiencies.

In simulations and real-world tests, TMRRT reduced average exploration time by over 7.5% and path length by over 19.8% compared to standard RRT, and by over 15.7% and 34.3% respectively compared to frontier-based approach (FA). The algorithm dynamically updates the topological map using BFS to compute distances, ensuring efficient traversal.

The method is designed for indoor environments and is compatible with common SLAM frameworks, offering a practical solution for autonomous map building without manual intervention.

Why it mattered

This work demonstrated that adding a topological memory layer to sampling-based exploration can significantly improve efficiency, a key step toward fully autonomous mobile robots in dynamic industrial settings. Reduced path length and time translate to lower operational costs and faster deployment in warehouses, factories, and other facilities.

“The results show that the algorithm can effectively improve the efficiency of robot autonomous exploration and is feasible in the actual environment.”

Source: 《机器人》期刊 (robot.sia.cn) · Published 2023-05-09 · “基于拓扑地图的移动机器人室内环境高效自主探索算法”