cs.ROMar 8, 2026

Reasoning Knowledge-Gap in Drone Planning via LLM-based Active Elicitation

Authors: Zeyu Fang, Beomyeol Yu, Cheng Liu, Zeyuan Yang, Rongqian Chen, Yuxin Lin, Mahdi Imani, Tian Lan

Organizations: George Washington University, Washington, D.C., USA · Northeastern University, Boston, MA, USA

Abstract

Human-AI joint planning in Unmanned Aerial Vehicles (UAVs) typically relies on control handover when facing environmental uncertainties, which is often inefficient and cognitively demanding for non-expert operators. To address this, we propose a novel framework that shifts the collaboration paradigm from control takeover to active information elicitation. We introduce the Minimal Information Neuro-Symbolic Tree (MINT), a reasoning mechanism that explicitly structures knowledge gaps regarding obstacles and goals into a queryable format. By leveraging large language models, our system formulates optimal binary queries to resolve specific ambiguities with minimal human interaction. We demonstrate the efficacy of this approach through a comprehensive workflow integrating a vision-language model for perception, voice interfaces, and a low-level UAV control module in both high-fidelity NVIDIA Isaac simulations and real-world deployments. Experimental results show that our method achieves a significant improvement in the success rate for complex search-and-rescue tasks while significantly reducing the frequency of human interaction compared to exhaustive querying baselines.

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