StreetNav: Leveraging Street Cameras to Support Precise Outdoor Navigation for Blind Pedestrians

TL;DR

StreetNav utilizes existing street cameras and computer vision to provide blind pedestrians with more precise outdoor navigation, addressing GPS limitations and involving community stakeholders.

Contribution

This work introduces a novel system that repurposes street cameras for outdoor navigation support for BLV pedestrians, combining technical and sociotechnical considerations.

Findings

StreetNav improves navigation accuracy over GPS.

System performance is affected by environmental occlusions.

Community engagement is integral to deployment considerations.

Abstract

Blind and low-vision (BLV) people rely on GPS-based systems for outdoor navigation. GPS's inaccuracy, however, causes them to veer off track, run into obstacles, and struggle to reach precise destinations. While prior work has made precise navigation possible indoors via hardware installations, enabling this outdoors remains a challenge. Interestingly, many outdoor environments are already instrumented with hardware such as street cameras. In this work, we explore the idea of repurposing existing street cameras for outdoor navigation. Our community-driven approach considers both technical and sociotechnical concerns through engagements with various stakeholders: BLV users, residents, business owners, and Community Board leadership. The resulting system, StreetNav, processes a camera's video feed using computer vision and gives BLV pedestrians real-time navigation assistance. Our evaluations show that StreetNav guides users more precisely than GPS, but its technical performance is sensitive to environmental occlusions and distance from the camera. We discuss future implications for deploying such systems at scale.