CHORAL: Traversal-Aware Planning for Safe and Efficient Heterogeneous Multi-Robot Routing

TL;DR

This paper introduces CHORAL, a semantic-aware planning framework for heterogeneous multi-robot routing that improves safety and efficiency by integrating scene understanding and robot capabilities into route planning.

Contribution

It presents a novel integrated framework combining semantic scene understanding with heterogeneous robot routing, enabling adaptive and capability-aware navigation.

Findings

Enhanced route safety and efficiency demonstrated in simulations.

Successful real-world deployment with three robotic platforms.

Open-source release of the CHORAL framework.

Abstract

Monitoring large, unknown, and complex environments with autonomous robots poses significant navigation challenges, where deploying teams of heterogeneous robots with complementary capabilities can substantially improve both mission performance and feasibility. However, effectively modeling how different robotic platforms interact with the environment requires rich, semantic scene understanding. Despite this, existing approaches often assume homogeneous robot teams or focus on discrete task compatibility rather than continuous routing. Consequently, scene understanding is not fully integrated into routing decisions, limiting their ability to adapt to the environment and to leverage each robot's strengths. In this paper, we propose an integrated semantic-aware framework for coordinating heterogeneous robots. Starting from a reconnaissance flight, we build a metric-semantic map using open-vocabulary vision models and use it to identify regions requiring closer inspection and capability-aware paths for each platform to reach them. These are then incorporated into a heterogeneous vehicle routing formulation that jointly assigns inspection tasks and computes robot trajectories. Experiments in simulation and in a real inspection mission with three robotic platforms demonstrate the effectiveness of our approach in planning safer and more efficient routes by explicitly accounting for each platform's navigation capabilities. We release our framework, CHORAL, as open source to support reproducibility and deployment of diverse robot teams.