Organizations: Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, Canada · Department of Mechatronics Engineering, Ontario Tech University, Oshawa, ON, Canada · Department of Earth and Space Science Engineering, York University, Toronto, ON, Canada · University of Toronto Institute for Aerospace Studies and the University of Toronto Robotics Institute, University of Toronto, Toronto, ON, Canada · Department of Mechanical and Materials Engineering, Queen’s University, Kingston, ON, Canada
We address the Person Goal Navigation (PersonNav) problem, enabling robots to search for people under realistic constraints on information accessibility and language uncertainty. This tackles the current solutions revolving around rigid person finding systems requiring exact knowledge of the individual for item-delivery in indoor settings. While the focus in literature is on learned methods using unavailable public or sparse data due to human privacy. We propose a planning framework that combines distance and semantic information about the recipient (habits and intent) weighted by the trust of the user-provided information. A synthetic benchmark of scenarios is also developed including actors, items, and requests to evaluate performance before real-world deployment aiming to simulate natural language human-robot interactions. Results show our informed search outperforms classical distance-based graph baselines, while semantics alone lead to ungrounded, sporadic search. Our method achieves strong gains over baselines, with an LLM-based variant performing comparably, and its explicit belief representation naturally supports future Bayesian filtering. Hardware tests demonstrate our method supports real-world embodiment able to leverage between semantic and distance information in a real setting. This work moves toward more intelligent mobile service agents capable of human-like, informed search in realistic environments to be leveraged in day-to-day use. https://anonymous.4open.science/r/personnavsite-4ED2/index.html.
Figures & tables
Type
Certainty
Example
None
-
Hey can you give this screwdriver to Jane?
Recency
High
This hammer is for Deshawn, he was right over by the lounge just a brief moment ago.
Behavioural
Low
Give this folder to Martin, not too sure but they’re sometimes at the lab.
Contextual
Low
Can you give Ramirez the whistle. He may need it for running drills today, but can’t say for certain, so try the field.
Behav. & Context.
High
Could you bring this laptop to Sana? She’s normally in the studio editing, and she’ll definitely need it for that.
TABLE I: Hint Type Taxonomy and Examples
Fig. 1: CSIR Framework Belief Generator
Fig. 2: Synthetic Scenario (Actor, Item, and Request) Generator
Fig. 3: Annotated Office, Hospital, and University Map (yellow circle markers indicate agent start locations)
Office
Hospital
Engineering University
Average
Method
Travel Eff.
Top-3 Acc.
Visited
Plan Time
Travel Eff.
Top-3 Acc.
Visited
Plan Time
Travel Eff.
Top-3 Acc.
Visited
Plan Time
Travel Eff.
Top-3 Loc.
Plan Time.
Graph-Based Planners
Random
0.22
0.17
9.42
-
0.22
0.19
7.75
-
0.21
0.20
8.92
-
0.22
0.19
-
Greedy
0.36
0.13
10.53
-
0.48
0.20
7.22
-
0.43
0.18
10.10
-
0.42
0.17
-
Held-Karp TSP
0.41
0.25
9.80
0.11
0.44
0.16
7.56
0.01
0.44
0.20
9.81
0.05
0.43
0.20
0.06
Semantic Planners
TABLE II: Simulation Summary Performance Accross All Environments
Fig. 4: Sankey Diagram to Show Hint and Certainty Distribution to Hint Correct/Incorrect (Office Environment)
Model
Train Method
Val. Acc.
Scenario Acc.
DeBERTa-v3-base
Fine-Tuning
0.86
0.67
Qwen3-0.6B-
Embedding
Linear Head
0.80
0.82
Qwen3-0.6B-
Embedding
Non-Linear Head
0.87
0.94
TABLE III: Certainty classification accuracy on validation and scenario datasets
Fig. 5: Violin Plot of Travel Efficiency Results Across All Methods (All Environments)
Belief Gen.
Travel Eff.
Top-3 Acc.
KL Div.
Gen. Time
Bi-Encoder
0.38
0.37
1.55
0.03
Cross-Encoder
0.48
0.47
1.86
0.01
LLM
0.52
0.58
1.36
2.16
CSIR (Belief)
0.51
0.56
1.58
3.70*
TABLE IV: Belief Generator Ablation Results (*Note: Gen. time is computed using the hospital and university results since parallelization was not introduced for the office yet)
Hint Type
Travel Eff.
KL Div.
None
0.46
1.63
Recency
0.80
1.49
Behavioural
0.67
1.80
Contextual
0.69
1.58
Behav. & Context.
0.77
1.42
TABLE V: Hint Type Ablation Results
Fig. 6: Hardware Experiment Recency and Behavioural Hint Requests
Natural language interaction provides an intuitive way for non-expert users to communicate with robotic platforms. However, transforming user requests into executable navigation actions remains a challenging task, requiring the integration of language understanding, environment perception, and autonomous navigation. This work presents a language-driven navigation framework that enables mobile robots to interpret user requests in natural language to move the robot to a destination and autonomously navigate towards it. The framework is composed of modular ROS 2 components that cooperate to transform natural language instructions into navigation actions. Given a natural language request referring to a target in the environment (e.g., "go to the mail box"), the system identifies the referenced object, estimates its position using RGB-D data, and generates a navigation goal, which is then executed through the ROS 2 Nav2 navigation stack. The ROS 2-based implementation facilitates portability across different robotic platforms, requiring only the configuration of the corresponding topics and services. The system is evaluated in both simulation and real-world scenarios using a TurtleBot3 Waffle and a Unitree Go2 robot with a RealSense camera. Experimental results show that the framework successfully interprets both direct commands and contextual requests, generates meaningful natural-language feedback, and navigates towards the desired target. These results demonstrate the feasibility of combining semantic perception and autonomous navigation to provide an intuitive human-robot interaction paradigm. Code will be released as open source upon acceptance.
Jose Martínez-Fajardo, Pablo Pueyo, Fernando Caballero +1
Assistive autonomous robots operating in multi-agent environments require efficient strategies to locate specific individuals among multiple residents. Current social navigation methods focus on reactive collision avoidance and trajectory adaptation, but lack mechanisms to proactively gather information through human-robot communication. We introduce Communication-enabled Social Navigation (CommNav). In this novel task, robotic agents actively seek assistance from residents to locate target individuals by requesting information about recent sightings, locations, and movements. To evaluate CommNav, we extend Habitat 3.0 to create Habitat 3.0c, a communication-enabled variant supporting multi-human environments with information exchange protocols. Adding our communication module (COMM) to a state-of-the-art social navigation model yields a 10 percentage-point improvement in Episode Success. We further investigate the transition from structured data to natural language by evaluating models trained on LLM-generated instructions and on colloquial instructions collected from a human study. Our experiments reveal that: (i) explicit human-robot communication substantially enhances multi-person navigation performance; (ii) pre-training COMM on a communication pretext task effectively addresses the challenge of occasional interaction signals; and (iii) the navigation policy is highly robust to natural, colloquial human language, achieving an episode success statistically similar to the model using perfect structured data.
Existing object navigation benchmarks usually tell an embodied agent which object category to find, such as microwave or chair. Human-facing embodied AI is often asked something less direct: "I need something to warm this food" or "the room feels stuffy." The agent must infer the object that can satisfy the need, find a scene-grounded instance, and decide whether the goal has been reached. We study this setting as intent-driven object navigation and introduce IntentionNav, a diagnostic benchmark for active object search from implicit human instructions. Each episode provides a free-text intent, RGB-D observations, and pose, but withholds the target object name. IntentionNav contains 500 intents over 176 Isaac Sim scenes and 64 target categories. Each intent is rewritten in four controlled instruction styles and annotated with one of four intent modes, separating surface phrasing from semantic cue type under matched geometry. This paired design supports analysis of target inference, language robustness, neighborhood reachability, and terminal success rather than only aggregate success. We evaluated three VLMs using a fixed active-navigation agent. Models identify the intended target in 48.3 percent of episodes and enter its 2 m neighborhood in 68.7 percent, but terminate successfully in only 24.9 percent and achieve grounded 1 m success in 5.5 percent. Success is highest for event-script intents (28.7 percent) and lower for physical-state and affordance intents (19.2 percent and 18.5 percent), showing that indirect human intent remains a bottleneck for target selection, visual verification, and terminal localization in active embodied search.
Lin Qian, Shijie Li, Sihao Lin +4
1The University of Manchester · 2A*STAR · 3Responsible AI Research Centre, Adelaide University +2