Safe Intersection Crossing for Pedestrians With Disabilities

US Transportation Collection2021PDFTech ReportSmith, Stephen F.Rubinstein, Zachary B.Mobility21, Carnegie Mellon UniversityUnited States. Department of Transportation. University Transportation Centers (UTC) ProgramUnited States. Department of Transportation. Office of the Assistant Secretary for Research and TechnologyMobility21, Carnegie Mellon UniversityUnited StatesMobile applicationsPedestrian detectorsPedestrian movementPersons with disabilitiesSignalized intersectionsMobility21 Project # 40459.14.108037669A3551747111Final ReportThe focus of this project has been on addressing some remaining obstacles to the general deployment of PedPal, a smartphone app that assists pedestrians with disabilities in safely crossing signalized intersections. Specifically, work has centered mainly on the design and development of two new capabilities: (1) an approach to localization that is accurate enough to enable detection of pedestrian arrival at a given corner of the intersection as well as active monitoring of progress during crossing, and (2) a scalable V2I/P2I communication infrastructure. With regard to localization, work has focused on utilizing the increasing availability of ultrawideband (UWB) sensors to overcome the inaccuracy of Bluetooth beacons positioned at intersection corners. Experiments have been performed to verify the accuracy of UWB devices in this context, extensions to the app have been implemented to allow receipt of distance data from UWB sensors positioned at the intersection, and algorithms have been developed for both reliable identification of intersection corners and for tracking of pedestrian progress through the intersection.125