Mobile Accessible Pedestrian Signal System

The NYC CVPD will deploy two pedestrian oriented applications: 1) a generalized warning to vehicles of pedestrians in the roadway and 2) support for visually impaired (blind) pedestrians. This section describes the street crossing support application for the visually impaired.

For the support for the blind, it is assumed that the application will be implemented using a portable personal device (e.g., smartphone) which supports both normal cellular operation and communications in the DSRC spectrum such that the pedestrian can monitor the messages associated with the CV applications and provide input to the traffic controller to request service where PED operation is actuated. Communications to/from the traffic controller will use DSRC (5.9 GHz. 1609.x, J2735) message sets and will be available at any intersection which includes an RSU.

The PED application is intended to use the MAP and SPaT messages to provide the intersection geometrics and the current status of the intersection displays (PED signals and vehicle signals) along with other confirmation information to assist the blind pedestrian in safely crossing the street.

The general operation is to use the MAP and SPaT information received by the smart device to orient the pedestrian, assist the pedestrian in confirming their location (street and cross street), and provide verbal information regarding the signal state and thus improve their ability to safely cross the street. The MAP message will include the location of the cross walks, and the application will use the pedestrian’s location and smartphone features to determine orientation and the SPaT message will instruct the condition of the intended route.

The PED application will also allow the pedestrian to issue PED calls to the intersection using the DSRC and the J2735 messages that are normally used for the priority signal request management.

Use of the SCMS is an important aspect of this application since it will require certificates to authenticate the SPaT and MAP messages from the RSU, and a special permission to use the PED call feature. Thus, there will be security and subscription issues with the use of the application including enrollment certificates for the application and the licensed user, as well as the normal privacy concerns to protect the PII which might be collected. It is expected that the operating certificates will be renewed on a weekly basis to avoid the Certificate Revocation List (CRL) issues and misbehavior detection management. This will also be an opportunity to work with the disabled community and the traffic signal operation to support safety improvements for this type of user