California Partners for Advanced Transportation Technology

Automated bus and truck systems hold the potential to improve road safety by eliminating some human error, increase the vehicle throughput by allowing vehicle convoying to shorten headways, and reduce costs associated with infrastructure, user time, and drivers. In this study, an automated bus system (ABUS) was compared with more-conventional light rail and bus-on-dedicated-lane (BDL) alternatives. A cost comparison (excluding accident costs) was also made among an automated freight trucking system (AHS-Truck), a no-build base condition, and configurations involving the addition of a conventional lane or a dedicated truck lane to the existing roadway. In both the ABUS and the Truck-AHS cases, the buses and trucks were assumed to operate in convoys. The benefits and costs were assessed from a societal perspective. Another comparison, based on shipping rates, was made among the AHS-truck, conventional trucking, and intermodal rail. The study concludes that the proposed bus alternatives could have substantially-lower costs than a functionally-equivalent light rail system for relatively low passenger volumes, but that there is no significant difference between the ABUS and BDL options at these volumes. At intermediate and high passenger volumes, ABUS and light rail may be the preferred alternatives, respectively. With regards to the freight systems, the analysis presented here indicates that the AHS lane performed better than the other two alternatives, primarily because of the lower vehicle operating and user costs. Additional research is recommended that addresses safety, demand change, and other impacts of the systems considered in this study.