Dynamic Mobility Application Policy Analysis: Policy and Institutional Issues for Intelligent Network Flow Optimization (INFLO)

The report documents policy considerations for the Intelligent Network Flow Optimization (INFLO) connected vehicle applications “bundle.” INFLO aims to optimize network flow on freeways and arterials by informing motorists of existing and impending queues and bottlenecks; providing target speeds by location and lane; and allowing capability to form ad hoc platoons of uniform speed. The policy team documented the following potential issues for INFLO: (1) Compliance with Speed Harmonization. Relying on voluntary compliance with dynamic speed harmonization (SPD-HARM) notices is likely to produce greatly varying results, at least initially. (2) Planning for Mixed-Mode Traffic. It could take a decade or more before INFLO achieves significant fleet penetration to produce realizable benefits. In the transition period, it may be necessary to plan for operations and maintenance of parallel systems (such as the use of changeable message signs) that must be operated consistently as well as to take other steps to ensure the safe and efficient operation of connected vehicle-equipped and non-equipped vehicles on the same roads. (3) Liability. Liability is a concern in all connected vehicle applications. For INFLO, liability concerns stem from three possible sources: the potential for missed messages because of equipment malfunction in individual vehicles; the driver’s reliance on data provided from multiple sources; and [with Cooperative Adaptive Cruise Control (CACC)] the proper functioning of automated vehicle controls. While the first and the third issue are likely addressable by the existing legal system (there is precedence for both), the second issue of parsing the multiple sources of data that have been fused together to form the INFLO message in order to understand the chain of liability, is still an emerging area in tort law. Research suggests that tort law will address INFLO liability issues in the future. (4) Public Acceptance and Use of Geo-Location Data. INFLO applications will use vehicle location data to send targeted messages to vehicles in specific areas. Although the geo-location data will not include any identifying information about the driver or vehicle, their use could raise privacy concerns among the public – including concerns about vehicle tracking – that might threaten acceptance of the applications. This issue is germane to the entire set of Connected Vehicle applications. Data privacy policies and best practices exist at the State and local levels and are available to address this issue. (5) In-Vehicle vs. Roadside Signage. INFLO’s use of in-vehicle messages raises a broad legal question of whether in-vehicle messages could take precedence over standard road signs (either static or changeable), or whether in-vehicle messages will always be considered “advisory” from a legal standpoint. It will be particularly important to resolve this issue in the case of SPD-HARM, where in-vehicle speed advisories may differ from posted (roadside) speed limits. (5) Technology Obsolescence. As with other connected vehicle applications, the various hardware and software components of INFLO will “age in place.” There is a risk that they will lose interoperability unless formal update and policies are established, including requirements for backward compatibility. Jurisdictions implementing INFLO would benefit from guidance and standards to ensure ongoing backward compatibility and interoperability. (7) Potential Driver Distraction. Visual devices displaying connected vehicle messaging have the potential to distract drivers and compromise safety. Some INFLO messages, due to their role in helping avoid congestion, may be especially alluring to drivers making decisions about route selection while traveling at high speeds. The National Highway Traffic Safety Administration (NHTSA) has issued guidelines for developing visual, in-vehicle displays that reduce distraction. (8) Equipment Interoperability and Certification. For INFLO to be fully and ubiquitously functional, standards may be required so that local infrastructure is fully interoperable with infrastructure on interstate highways and major state roads. (9) Messaging Standards and Priority. Under INFLO, new technology will provide in-vehicle messages about congestion and speed advisories. The role of INFLO in providing this type of information raises potential policy issues about the need for message standards, to insure that INFLO messages comply with all applicable Manual for Uniform Traffic Control Devices (MUTCD) standards.