APPENDIX B

Case Study on Truck Platooning

The EAR Program made a concentrated investment in research on truck platooning (TP) under its 2013 BAA. This effort built on a 2007 project awarded to California PATH to explore different applications of vehicle-to-vehicle communication and control. Although the Program only sponsored three projects on TP under that BAA, the research results influenced downstream work by other researchers and sponsors.

B.1 Definition and Timeline

TP refers to a system that allows two or three freight or cargo trucks to travel in very close succession with a buffer distance of only 50 feet—much closer than the safe following distance for trucks driven only by humans. The primary benefit of TP is expected to be fuel cost savings. By traveling in the “draft” created by the lead truck, the following trucks encounter much lower wind resistance and therefore consume less fuel. Note that TP is not predicated on autonomous vehicle technology. In a truck platoon, each truck is assumed to have a human driver who has control of the vehicle. The platooning system supplements human control by taking over the braking and acceleration functions to maintain close following distances safely.

Research on TP dates back to the 1990s. An effort in California called “The Phoenix Project” explored opportunities for gaining roadway efficiency through managed lane operations. A follow-on demonstration project proposed the development of technology to enable semi-automated convoys of two or three heavy trucks. Results of the demonstration were summarized in a 2005 report by the UC Berkeley Institute for Transportation Studies. The report detailed performance parameters and limitations involved in deploying TP technology, even on a test basis. Steven Schladover of the California PATH program at the Institute, the author of the report, was awarded an EAR project in 2007 on “vehicle-infrastructure integration,” which included a project exploring TP. The EAR Program decided that broader developments in autonomous vehicle technology, plus intensive interest in the potential benefits, helped to justify a new set of investigations into TP.

B.2 TP Research: Initiation and Evolution

TP emerged as a potential EAR research topic during Initial Stage Investigations during 2011 and 2012. The investigations established that after the early work in California and some other locations in the early 2000s, no funding had emerged to support further development of the concept. TRB’s 2012 Road Vehicle Automation Workshop also seemed to highlight the potential of TP for further development.

B.2.1 Rationale for TP as an EAR Topic

TP attracted interest because of parallel developments in the closely related field of Cooperative Adaptive Cruise Control (CACC). CACC was characterized as the bundle of technologies, including in-vehicle sensors, vehicle-to-vehicle communications, and Global Positioning System (GPS), that enabled vehicles to operate in closer proximity while using partial automation and driver alerts to prevent collisions. TP garnered specific interest at FHWA because of benefits in fuel efficiency, roadway efficiency, and safety. Successful implementation of TP would enable highways to support higher freight volumes without increasing lane capacity. It would also reduce fuel consumption by freight trucks—a small marginal benefit that would generate substantial absolute cost savings due to the scale of truck fuel consumption. TP could also introduce automated safety controls in collision avoidance and other applications to reduce injuries and fatalities from accidents involving heavy trucks. In the longer term, TP deployment could lead to modifications in roadway design to accommodate higher truck volumes.

B.2.2 TP Project Selection

The EAR Program received seven proposals in response to the solicitation focused on TP. Proposals from California PATH at UC Berkeley and from Auburn University were selected for funding over proposals from the University of Michigan, Virginia Tech, Lockheed Martin, Battelle Memorial Institute, and a second, more limited proposal from California PATH. Those projects, plus related projects conducted by Auburn and UC Berkeley, are summarized in Table B-1.

For California PATH’s “Assessing the Feasibility of Deploying Partial Automation for Truck Platooning,” the extensive TP research experience of both the California PATH team and the partnered Volvo team was highly valued. PATH had already been developing and testing automated truck platoon systems under a combination of sponsorship from Caltrans and the FHWA EAR program. Volvo had already performed TP work under the European Commission’s SARTRE (Safe Road Trains for the Environment) project and was extending that work under a

Table B-1. TP-related projects funded by the EAR Program.

new European project, TEAM (Tomorrow’s Elastic Adaptive Mobility). The project also seemed to be well-planned with a strong technical approach, plus convenient stopping points between phases in case FHWA decided to terminate work on the project early.

The Auburn “Heavy Truck Cooperative Adaptive Cruise Control” project was a smaller, more affordable project relative to the California PATH proposal, with a greater focus on providing an immediate business case for TP. It was seen by the proposal review panel as providing the best value and most practical solution of all the proposals. The panel also appreciated the proposal’s substantial emphasis on the aspects of ROI required to encourage industry adoption. The proposal’s approach to industry outreach was seen as thorough and essential to market adoption of TP innovations. Like the California PATH project, the Auburn project team was seen as having a strong background in implementing technology on heavy vehicles as well as experience with the business concepts of trucking companies. The panel also appreciated the Auburn partnership with the American Transportation Research Institute (ATRI), given ATRI’s ongoing research in this field. Contractual relationships and listed costs seemed to be included for all team members, as well as fair division of labor and promising avenues for potential outreach. In contrast, many of the unfunded proposals were viewed as providing inadequate transition support, or they lacked partners involved in truck development.

B.2.3 TP Project Oversight and Management

For TP projects, PIs noted that the AOTRs had a “hands-off” approach to oversight. FHWA oversight required annual reports, but otherwise the project officer would respond to requests from researchers but not initiate much communication. The researchers appreciated this approach because they felt it provided more freedom to explore research opportunities and options without interference. They contrasted this approach to the practice at other research funding agencies, such as DOE.

Because both TP projects were led by experienced PIs, they had formed complete teams with the necessary resources to conduct their research. California PATH partnered with Cambridge Systematics, Inc., for technical expertise based on earlier demonstration work on the I-710 Corridor with LA Metro and Gateway Cities Council of Governments. Volvo provided trucks for testing and assisted with the retrofitting of the Volvo trucks so that they could be used for testing. The NRC contributed testing space for controlled testing at Transport Canada’s Motor Vehicle Test Centre in Blainville, Quebec. In the Auburn project, ATRI took the lead in all business case analyses, including overall industry analysis, conduct of focus groups, and provision of real-world data on trucking operations to support other analyses. Peloton provided their proprietary driver-assistive TP technology for use in the study. Peterbilt provided trucks and the time of industry engineers to guide the research and provide expertise to review specific equipment-related findings. Meritor WABCO provided their OnGuard Collision Mitigation System to form part of the technology foundation for the platooning system.

The EAR Program continued to support the TP projects through regular briefings to FHWA offices and by encouraging conference presentations. The program office also funded development of a transition plan for TP technology, but it is not clear whether the plan was implemented.

B.3 TP Research Outcomes

The EAR Program’s investment in TP has influenced follow-on investment by other research sponsors and also shaped the research agenda of other academic centers. Researchers have credited two EAR-funded projects, one led by Auburn and the other led by California PATH, with

identifying key technical and policy challenges limiting TP deployment. These include human factors considerations (among truck drivers and other drivers), state regulations on truck operations, potential wear on roadways and bridges that must support closely spaced truck convoys, and TP performance on hilly or winding roads (where close following may not produce substantial fuel efficiencies).

Several projects at FHWA built on the EAR-funded work:

“Preliminary Interaction Between Heavy and Light Vehicles at Level 1 CAV” evaluated the effects of dedicated short-range communications and long-term evolution (LTE) connectivity on mixed vehicle platooning. It also investigated critical safety issues that could negatively affect mobility using FHWA-provided trucks at the Aberdeen Test Center. The project was funded by the Office of Operations Research and Development from 2016 through 2020.

“Human Factors Issues for Truck Platooning” addressed some of the critical human factors issues related to driver behavior in the presence of truck platoons. Two key topics included the behavior of drivers entering and exiting freeways in the presence of truck platoons, and whether an external visual display/indication on the platooning trucks improves how drivers react to the presence of truck platoons. This project was funded by the Office of Safety Research and Development from 2017 through 2020.

Phase 1 of “Truck Platooning Early Deployment Assessment” determined metrics for evaluating Phase 2 experiments on future connected and automated vehicles (CAV) technologies. The primary purpose of the Phase 2 field test is to accelerate the deployment of CAV technologies for freight movement through the development of a TP pilot deployment that includes in-service freight hauling. This project is being conducted from 2020 through 2023 by the Saxton Transportation Operations Laboratory. It is funded directly by the FHWA Office of Federal Highway Administrator.

“Truck Platooning Effects on Girder Bridges” is an FHWA-funded project, co-sponsored by Nebraska’s DOT, which evaluates the Strength I limit state for steel and prestressed concrete I-girder bridges designed with load and resistance factor design and load factor design. The study considered different girder spacings, span lengths, numbers of spans, types of structures, truck configurations, numbers of trucks, and adjacent lane-loading scenarios for effects on bridge wear.

The most significant follow-on project is a major demonstration project funded by FHWA. Following the EAR-funded projects, this initiative supported three “Level 1” demonstrations of TP systems intended to generate proposals for a Level 2 demonstration. The three Level 1 teams were led by California PATH, Battelle Memorial Institute, and CDM Smith. (Auburn University proposed a project but it was declined.) The Level 2 demonstration was awarded to California PATH, which also secured participation from a freight trucking company (Roly’s Trucking in California). This project has generated substantial data on TP performance under actual highway conditions.

TP was also a focus of projects conducted more recently at NHTSA and FMCSA. These projects examined safety issues and potential hazards associated with TP and also how law enforcement would manage TP convoys.

DOE’s National Renewable Energy Laboratory led a parallel TP research effort from 2014 through 2018, funded by Advanced Research Projects Agency–Energy and the Office of Energy Efficiency and Renewable Energy. This effort was not coordinated with the EAR-funded projects, but project reports were cited in its final report. DOE continues to fund some exploration of TP technologies. Researchers reported that other TP projects are being funded by the U.S. Army (for off-road conditions).

Development and deployment of TP systems has not met initial expectations expressed at the start of the EAR Program projects. Analysts attributed this to conditions that could not have been predicted at the time:

• Auburn University’s project encountered limitations due to restrictions on data-sharing imposed by its TP technology partner, Peloton. Peloton was subsequently acquired by Waymo, including all intellectual property, which further limited technology transition options.
• Private industry, attracted by the rapid advances in autonomous vehicle technology at firms like Tesla and Waymo (a subsidiary of Alphabet, Inc.), began to pursue higher levels of truck automation. That research pursues the promise of reducing labor costs by eliminating drivers from trucks. Although far from the point of implementation, this trend moved attention of truck manufacturers away from TP.
• FHWA learned through its demonstrations that freight trucking companies rarely schedule trucks to run in two- or three-truck convoys over long distances. Supply chain pressures require that trucks be sent on the road immediately when loaded. Wider adoption of TP technology may require broader changes in the transportation and logistics industries.

Although there are relatively few tangible outcomes from the EAR Program’s research on TP, this is due to environmental circumstances. The EAR Program does receive credit from observers for helping to spur TP research at FHWA, state DOTs, and other agencies. In particular, by generating academic datasets open to other researchers, the EAR Program created a key input to downstream research efforts.