PI: Bharat Pathivada, Ph.D.*
Co-PI: Yao-Jan Wu, Ph.D., P.E.*
PM: Blake Olofson
Sponsor: City of Tucson
Aug. 2026 - July 2027*
*Current Phase
The Center for Applied Transportation Sciences (CATS) has partnered with the City of Tucson since August 2017 to optimize traffic signals and improve mobility, safety, and efficiency across the city's transportation network.
Through this multi-phase effort, multi-source traffic data has been automatically collected or estimated citywide. The UA-STAR website (Tucson.UA-Star.org), developed in Phases 1-5, was upgraded and replaced by the UA-SMART Tool (uasmart.org) in Phase 6, expanding the data analytics capabilities used to support signal re-timing and safety studies. The success of earlier phases led to the continuation of the partnership through Phase 10, reflecting the City's continued confidence in CATS as a trusted technical partner.
Phase 10 continues signal re-timing and evaluation efforts on two selected corridors, Prince Rd and Swan Rd, while also expanding the UA-SMART Tool and evaluating the safety and operational impacts of protected/permissive left-turn (PPLT) versus protected-only left-turn operations.
Through this multi-phase effort, CATS works closely with City staff to develop practical, data-driven solutions that enhance mobility, improve roadway safety, and support Tucson's long-term transportation goals.
Phases 1-9: PI: Yao-Jan Wu, Ph.D., P.E.
Phases 5 & 6: Co-PI: Xiaofeng Li, Ph.D.