Strategies to Advance Automated and Connected Vehicles (2017)

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3- V2I safety applications (e.g., red-light violation warnings, curve speed warnings, and work zone warnings). - V2V safety applications (e.g., forward collision warnings, intersection movement assist, left-turn assist, and do-not-pass warnings). - V2X or vehicle-to-everything, as in the Internet of Things; for example, a wearable device in a highway worker’s safety vest that warns drivers of the person’s location. However, non-safety critical applications (e.g., weather advisories and eco-ap- proach and departure at signalized intersections) could also be achieved using other wireless communications. At present, the V2I and V2V applications solely provide driver alerts; they do not control the operation of the vehicle. Regulatory Context In September 2016, the National Highway Traffic Safety Administration released the official Federal Automated Vehicle Policy, issued as “guidance rather than in a rulemaking capacity in order to speed the delivery of an initial regulatory framework and best practices to guide manufacturers and other entities in the safe design, development, testing, and deployment of Highly Automated Vehicles (HAVs).” The policy reaffirms that states retain their responsibilities for licensing and registering vehicles, defining and enforcing traffic law, and regulating insur- ance and liability requirements and policies. The framework envisions that each state’s AV-related policies and regulations be administered by a single lead agency and associated technology committee. The issues and actionable strategies cov- ered in this document are those that would be relevant to such entities. How AVs and CVs Could Lead to Positive Societal Outcomes By what mechanisms might AVs and CVs create desirable outcomes for society, either by encouraging direct positive effects or reducing negative ones? Through inferences based on reviews of the literature, the research team identified ways in which CVs and AVs could lead to those desirable outcomes. Driving Externality Connectivity (Full V2X) Autonomy* (L4,5) Shared Autonomy (L4,5)** Electrification*** Safety Congestion Emissions Land Use Mobility Potential Benefits of Connectivity and Automation *Autonomy is defined for this purpose as individually owned vehicle. **Shared Autonomous Vehicles (SAV) are on-demand self-driving vehicles supporting shared rides as part of a pri- vately or publicly managed fleet. ***While not a focus of this NCHRP research, the team provides assumptions of potential benefits of electrification based on known literature. Strong benefits Weakest benefits/no impact Some expected benefits Uncertain impact

4TRAFFIC CRASHES When individuals drive a vehicle, they not only increase their own risk of a crash and its associated costs, they also increase crash risks and costs for other motor- ists, pedestrians, cyclists, and society in general. V2V safety applications could mitigate these risks by addressing most vehicle crash types if the V2V applications are demonstrably effective and widely used, the driver-vehicle interface performs well, and there is sufficient market penetration. An increase in benefit could be obtained through V2I safety applications. Even without CVs, AVs could reduce most driver-related errors, which account for a vast majority of traffic crashes, but AVs also might introduce new types of errors. Flawed hardware or software could cause accidents due to errors that humans would not make. AVs and CVs both cre- ate cybersecurity risks. Level 3 AVs could also introduce risks posed by inattentive drivers who fail to take safe control of the vehicle when needed. Early research suggests that these technologies have promise, but the safety benefits of AVs and CVs are not guaranteed. CONGESTION As the number of vehicles on a road increases past a certain density, vehicle speed and throughput decrease, causing congestion. Each additional driver adds to the congestion but does not bear the full cost of that effect. Ultimately, it is unclear how AVs and CVs will affect congestion; the literature in this area shows mixed results for a variety of different traffic measures under varying conditions. Conges- tion occurs on a regular basis (i.e., recurring) and on a sporadic basis (i.e., non-re- curring). CV applications could mitigate non-recurring congestion by reducing delays caused by safety incidents. CV mobility applications could reduce recurring congestion by increasing system efficiency and enabling CV-facilitated truck platoons. Widespread adoption of V2V capabilities, widespread V2I infrastructure, and interoperability among mobility applications would maximize these impacts. AVs that are safer than human drivers could reduce the frequency of crash-re- lated delays. In addition, more closely-spaced AVs could enhance traffic flow. At the same time, a proliferation of on-demand, shared AVs (SAVs) could put more Even without CVs, AVs could reduce most driver-related errors, which account for a vast majority of traffic crashes, but AVs also might introduce new types of errors. Pavel L Photo/Shutterstock.com

5vehicles on the road and increase congestion. Alternatively, multi-occupancy SAVs could reduce the number of vehicles on the road. Although the travel delay caused by congestion may be redefined if the occupant in an AV can be produc- tive while waiting in traffic, there still might be the need to minimize associated vehicle miles traveled (VMT) growth because it contributes to other negative effects, such as pollution. The net effects of AVs and CVs on congestion have yet to be fully understood or predicted. POLLUTION Vehicles emit local air pollutants (e.g., particulate matter, hydrocarbons, nitrogen oxides, and carbon monoxide) and global air pollutants (greenhouse gases). When someone drives a vehicle, he or she reduces the air quality and adds to noise pol- lution in surrounding areas. That person also imposes the costs of climate change on the global society. AVs could mitigate these effects by leading to reduced ve- hicle production rates and parking needs, and to increased use of smaller, electric vehicles and eco-driving. On the other hand, by increasing safety and improving the convenience of vehicle travel, AVs and CVs could lower transportation costs, which could increase VMT. While this increase in VMT may facilitate additional eco- nomic activity or enhanced quality of life, it may also produce negative environ- mental impacts that would need to be mitigated. LAND DEVELOPMENT Land devoted to automobile infrastructure and dispersed development pat- terns—while historically increasing mobility and decreasing travel costs—may also impose negative environmental, economic, and public health effects on soci- ety. AVs and CVs could increase safety, improve convenience of vehicle travel, and lower transportation costs, but these effects might lead consumers to take more trips and travel more miles in order to access lower priced land and rural locations, exacerbating inefficient land-use patterns. On the other hand, if fully autonomous (SAE Levels 4 or 5) AVs reduced the need for parking adjacent to destinations, land dedicated to parking in urban areas could be assigned to other, more beneficial uses. The largest effects would be in dense urban areas, where land is very expen- sive, while impacts might be less substantive in most areas of the country. MOBILITY Older adults, youths under age 16, and individuals with disabilities have limited access to desired destinations, activities, and services. The existing transportation infrastructure does not completely address the limited mobility of this population. Levels 4 and 5 AVs could mitigate this negative externality by enabling significant improvements in access and mobility for such individuals. This is particularly true for those who live in areas with few alternative modes. Less-than-full automation (Level 3) and CVs would not reduce this negative externality. Ultimately, it is unclear how AVs and CVs will affect congestion; the literature in this area shows mixed results for a variety of different traffic measures under varying conditions.