Toward Deployment of Adaptive Transit Signal Priority Systems

This document reports the continuous efforts conducted by California PATH Program on the development and implementation of an Adaptive Transit Signal Priority (ATSP) system. The ATSP system has three distinguished features, including: (1) providing priority to transit vehicles while making a tradeoff between bus delay savings and the impacts on the rest of the traffic, (2) utilizing existing AVL/communication system already instrumented on buses to continuously monitor bus locations and predict bus arrival times to intersections and to request signal priority, and (3) building upon closed-loop signal control systems with 170E controllers. These features allow ATSP to have potential for wide-scale implementation. This report describes the development of ATSP algorithms, the field testing results of the prototype ATSP system and the feasibility analysis for utilizing existing transit communication for ATSP.