Structures as Sensors Lab

Neighborhood Drive

Privacy-preserving mobile sensors on community vehicles map neighborhood conditions in San José, allowing cities and community organizations to better serve unhoused residents.

Project Introduction

Neighborhood-scale perception with privacy built in.

Serving unhoused residents well depends on current, ground-level knowledge of where people are. People living in RVs, encampments, and shelters move across neighborhoods over weeks and days in response to their own needs and external stressors, particularly displacement. Service providers and city agencies need to know where they move and how their needs have changed, including environmental conditions like air quality, heat, and sanitation.

01

Privacy by design

Faces, license plates, and clothing are filtered out at the source, leaving only the shapes and motion the map actually needs.

02

Mobile, not fixed

Sensors ride on vehicles already serving the community, covering far more ground than fixed cameras at a fraction of the cost.

03

Community-engaged

The system is shaped by ongoing surveys with the people it affects. Their input informs our definition of "privacy-preserving" and determines what gets sensed and how.

Our Work
01

Privacy-preserving vehicle detection

A pipeline that turns RGB video from vehicle-mounted cameras into bounding boxes around vehicles, with appearance details removed at the source. Thermal data downstream identifies which detected vehicles are lived-in.

02

Environmental sensing

Gas, temperature, humidity, and noise sensors map ambient conditions block by block, capturing air quality, heat exposure, and acoustic environments along service routes.

03

Built-environment computer vision

Detection of supportive infrastructure, such as toilets and handwashing stations, and deterrent infrastructure, such as planters and concrete blocks, from street-level imagery.

04

Federated learning

Models are trained across multiple vehicles without centralizing raw data, and used to predict effective routes for service providers.

05

Community perspectives

Surveys with Loaves and Fishes clients on privacy and monitoring preferences, alongside public opinion polling on policies affecting unhoused residents. In partnership with the City of San Jose.

Project Team

Collaborators across sensing, cities, and community-centered AI.

PIs
Professor Hae Young Noh

Project Leader

Prof. Hae Young Noh

Department of Civil and Environmental Engineering, Stanford University

Jackelyn Hwang

Co-PI

Prof. Jackelyn Hwang

Department of Sociology, Stanford University

Sarah Billington

Co-PI

Prof. Sarah Billington

Department of Civil & Environmental Engineering, Stanford University

Carlee Joe-Wong

Co-PI

Prof. Carlee Joe-Wong

Department of Electrical & Computer Engineering, Carnegie Mellon University

Pei Zhang

Co-PI

Prof. Pei Zhang

Department of Electrical and Computer Engineering, University of Michigan

Students / Researchers

Postdoctoral Researcher

Dr. Amelie Bonde

Department of Civil & Environmental Engineering, Stanford University

PhD Student

Jatin Aggarwal

Department of Civil & Environmental Engineering, Stanford University

PhD Student

Zhili He

Department of Civil & Environmental Engineering
HKUST & Stanford University

MS Student

Shang Gao

Department of Civil & Environmental Engineering, Stanford University

PhD Student

Sarah-Eve Dill

Department of Sociology, Stanford University

PhD Student

Daria Fontani Herreros

Department of Civil & Environmental Engineering, Stanford University

PhD Student

Morgan Tompkins

Stanford University

MS Student

Janhavi Purkar

Stanford University

PhD Student

Yi Hu

Department of Electrical & Computer Engineering, Carnegie Mellon University

PhD Student

Baris Askin

Carnegie Mellon University

PhD Student

Jong-Ik Park

Carnegie Mellon University

PhD Student

Blessed Guda

Carnegie Mellon University

PhD Student

Julia Gersey

Department of Electrical & Computer Engineering, University of Michigan

PhD Student

Tomas Fernandez

University of Michigan

Previous Members

Previous Member

Tianyuan Huang

Stanford University

Previous Member

Shounak Ray

Stanford University

Outcomes

Publications and presentations from the NeighborDrive collaboration.

01

Conference Workshop Paper

NeighborDrive: Privacy-preserving Neighborhood Sensing through Outreach Vehicles

Best Paper Award, 2nd Place

Presented at the SocialSys workshop, ACM Sustainability Week Companion 2026, in Banff, AB, Canada (June 22-25, 2026).

Aggarwal, J., Gao, S., Bonde, A., He, Z., Gersey, J., Fernandez, T. S., Rejeev, R., Zhang, P., & Noh, H. (2026). NeighborDrive: Privacy-preserving Neighborhood Sensing through Outreach Vehicles. ACM BuildSys 4th International Workshop on Social Infrastructure Systems (SocialSys'26), June 22-25, 2026, Banff, AB, Canada.

02

Conference Paper

GLUE: Gradient-free Learning to Unify Experts

Presented at IEEE ICASSP 2026.

Park, J. I., Chaudhari, S., Pranav, S., Joe-Wong, C., & Moura, J. M. (2026, May). GLUE: Gradient-free Learning to Unify Experts. In ICASSP 2026-2026 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp. 2681-2685). IEEE.

03

Conference Workshop Paper

Human vs. Machine: Comparing Urban Condition Classification Methods from Vehicular Vision

Presented at BuildSys 2025.

Julia Gersey, Troy Zhong, Jiale Zhang, Jesse Codling, Jackelyn Hwang, and Pei Zhang. 2025. Human vs. Machine: Comparing Urban Condition Classification Methods from Vehicular Vision. In Proceedings of the 12th ACM International Conference on Systems for Energy-Efficient Buildings, Cities, and Transportation (BuildSys '25). Association for Computing Machinery, New York, NY, USA, 427-430. https://doi.org/10.1145/3736425.3772319

Workspace Outputs

One image, multiple privacy-preserving representations.

Annotated

SAM3 mask overlays and detection boxes for prompt verification.

Privacy

Human regions replaced by solid black for identity protection.

Depth Mask

Only human regions become Depth-Anything-V2 depth; the rest remains RGB.

Estimated Depth

The complete scene rendered as a colorful Depth-Anything-V2 depth image.