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From page 351... ... Appendix F Connected and Automated Vehicle Technology Impacts on Future Interstate Highway System Steven E Shladover EXECUTIVE SUMMARY This appendix provides an overview of the implications that development and deployment of connected and automated vehicle (CAV) Read the entire page →
From page 352... ... 352 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM and so a single national deployment profile cannot be assumed. Given these uncertainties, decisions about future roadway infrastructure should not be finely tuned to specific assumed technology deployment schedules, but rather need to be robust with respect to a wide range of possible CAV deployment patterns. Read the entire page →
From page 353... ... APPENDIX F 353 and human–machine interfaces to exchange information with drivers and travelers. In recent years, attention has been focused specifically on CV systems and AV systems, and on their combination (CAV systems) Read the entire page →
From page 354... ... 354 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM All but the last of these are time-critical and safety-critical applications that need very low-latency and high-reliability communications. For most of these applications, the communicated data are used to augment the data acquired by onboard remote sensors, which remain the primary source of data about time-critical and safety-critical conditions. Read the entire page →
From page 355... ... APPENDIX F 355 commercial developments and economies of scale than some of the other technologies. The National Highway Traffic Safety Administration (NHTSA) Read the entire page →
From page 356... ... 356 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Automated Vehicle Systems AV systems have had a considerably longer and more irregular history than CV systems, with many ups and downs since the concept of road vehicle automation was introduced by Norman Bel Geddes in the General Motors Futurama exhibit at the 1939–1940 New York World's Fair (Bel Geddes 1940) Read the entire page →
From page 357... ... APPENDIX F 357 system in a variety of ways, but there are large uncertainties about how far in the future those will become available. On the other hand, the lower levels of automation are imminent and transportation officials need to understand their limitations and their implications for the transportation system. Read the entire page →
From page 358... ... 358 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM increase to only 7.2 percent by 2020. Level 2 partial automation systems have recently been introduced on high-end vehicles, and will be introduced on premium vehicles from more manufacturers within the next few years. Read the entire page →
From page 359... ... APPENDIX F 359 At Level 0, the systems do not perform dynamic driving tasks on a sustained basis, but they can warn drivers about hazards or even intervene for a brief time to avoid or mitigate an imminent crash (automated emergency braking or lane departure prevention) Read the entire page →
From page 360... ... 360 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM with cooperative infrastructure elements should make it possible to start implementing this capability within this decade. • Automated trucks on dedicated truck lanes are another high-value niche application of automation that should be possible within the decade by restricting access to those lanes to trucks (Shladover 2001) Read the entire page →
From page 361... ... APPENDIX F 361 drive. This is the concept that captures the public imagination by allowing full "electronic chauffeur" service, including • Electronic taxi service for people who are not able to drive (too old, too young, physically impaired) Read the entire page →
From page 362... ... 362 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Demand-Side Impacts The CAV technologies are likely to have diverse impacts on the demand for travel, and the net impact is likely to be challenging to estimate because of the large uncertainties on both the positive and negative expected impacts. These demand effects are expected to include • Reductions in the need to travel, with potential for substituting telecommunications activities for travel; • Changes in trip scheduling, with better information promoting better choices to avoid the worst congestion and safety challenges; • More efficient selection of routes and modes based on better information about all viable alternatives; • Reduction in disutility of travel time, encouraging realization of latent demand and potentially inducing new travel demand through locational changes; • Increased efficiency and improved quality of service by trucking, encouraging freight modal shift toward trucking; • Improved transit service quality, encouraging passenger mode shifts away from private personal vehicles and toward transit; and • Electronic chauffeuring providing affordable mobility for travelers who cannot drive, encouraging them to travel more than before. Read the entire page →
From page 363... ... APPENDIX F 363 • Changes in highway lane capacity based on differences in vehicle following gaps, • Increases in highway bottleneck throughput based on more responsive traffic management and ability to implement situationdependent speed control, • Reduction in traffic disturbances from lane drops and entrance and exit ramp flows through coordinated vehicle merging, • Improved ability to manage incidents based on higher-fidelity information for incident responders and for travelers, and • Improved multimodal corridor management in urban corridors through enhanced information and control mechanisms. Mode-Specific Impacts The later sections of this appendix address the freight and passenger movement impacts separately because there are some significant differences between them on both the supply and demand sides. Read the entire page →
From page 364... ... 364 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM The most important principle to take away from this observation is that decisions about the future of our transportation infrastructure need to be robust with respect to technological uncertainty, rather than being highly tuned to specific predictions about technological outcomes. Each technology forecast should be viewed as a fuzzy estimate, with a wide range of possible outcomes that could range from much faster and higher capabilities to much slower and lower capabilities than the nominal prediction. Read the entire page →
From page 365... ... APPENDIX F 365 1. How capable will the automation technology be of performing the complete dynamic driving task within various operational design domains, and when will those capabilities first become available for use by the general public? Read the entire page →
From page 366... ... 366 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM the vehicles and the roadway infrastructure to function as a well-integrated system. This means that it will be increasingly difficult to treat the National Highway System as a single consistent system unless extraordinary efforts are invested to promote nationwide consistency and uniformity. Read the entire page →
From page 367... ... APPENDIX F 367 respective impacts are discussed in largely qualitative terms, since detailed quantitative estimates would be speculative at this early stage. The passenger travel demand implications of CAV technology are discussed first, followed in subsequent sections by the freight travel demand and the combined supply-side implications. Read the entire page →
From page 368... ... 368 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Teleconferencing and Virtual Reality Reducing Longer-Distance Trips to Meetings Teleconferencing is already having an influence on reducing long-distance business travel based on the potential to save significant time and money, but it is still a relatively narrow application because it is not yet a very convincing substitute for face-to-face contact for many purposes. There is a potential for great growth here, particularly as virtual reality or augmented reality can provide an impression of more direct personal contact among people who do not already know each other. Read the entire page →
From page 369... ... APPENDIX F 369 became technologically feasible and affordable -- a prospect that is likely to come in the very distant future, if ever (for reasons to be explained in the section on effects at different planning horizons) Read the entire page →
From page 370... ... 370 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Parking Information Reducing Wasted Travel Seeking Parking A significant proportion of urban driving is currently wasted mileage by drivers seeking parking spaces (Shoup 2007) Read the entire page →
From page 371... ... APPENDIX F 371 it becomes particularly challenging to estimate what the net changes in demand are likely to be. Empty Backhaul Trips for Repositioning Shared-Use Vehicles to Make Their Next Trip The concept of shared-use vehicles (car sharing) Read the entire page →
From page 372... ... 372 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM from their workplaces. This triggers one of the major potential concerns about highly automated driving -- that it will release significant latent demand and may induce new travel demand by encouraging urban sprawl. Read the entire page →
From page 373... ... APPENDIX F 373 automated driving system to drive the empty vehicle back and forth between the user's destination in the urban core and a remote parking facility on cheaper land in the outskirts. This would create extra empty mileage for the round trips between the travel destination in high-cost locations and the remote parking sites, which is likely to have significant adverse implications for traffic volume, energy, and the environment. Read the entire page →
From page 374... ... 374 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM The CAV influence on service improvements includes • Better real-time traffic and weather information enables truck operators to choose better routes and dynamically change routes to avoid delays, reducing delays and improving delivery time reliability. • Operation of trucks using cooperative ACC and platooning increases the capacity and smooths traffic on congested truck corridors, reducing delays and improving reliability of delivery times. Read the entire page →
From page 375... ... APPENDIX F 375 transferred between drivers (who would still drive the local pickup and delivery portions of the trips) and the automation system. Read the entire page →
From page 376... ... 376 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Collision Warning and Avoidance Systems These systems could potentially reduce current crash rates by about half. Since crashes have been estimated to cause about 28 percent of the congestion on urban freeways (Varaiya 2005) Read the entire page →
From page 377... ... APPENDIX F 377 at times away from the peak. This could of course also be coupled with congestion charging via CV technology, adjusting the prices for travel based on time of day or current conditions, further encouraging peak spreading. Read the entire page →
From page 378... ... 378 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM truck lanes or corridors were available on key Interstates to segregate the trucks from the hazards posed by recklessly driven cars and motorcycles. This is an alternative that should be explored on the infrastructure side now so that it could be implementable in 10 years, when the driverless platoon follower technology could become feasible for use within such a restricted ODD. Read the entire page →
From page 379... ... APPENDIX F 379 better integration with local arterial traffic operations will be necessary as part of the implementation to avoid simply shifting the bottlenecks to the arterials and freeway entrances and exits. The benefits to the freeway network operations should be sufficiently large to justify the relatively modest investments that are likely to be required for the improved arterial coordination. Read the entire page →
From page 380... ... 380 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM management, and operations. This is a broad set of potential impacts, which can at best be discussed in semiquantitative terms, rather than getting into highly refined numerical exercises. Read the entire page →
From page 381... ... APPENDIX F 381 The net effects on freeway operations will probably be too small to measure throughout most of the country. • Truck CACC and platooning systems will be used by some major truck fleets on major freight corridors and will be exposing the public to the experience of sharing the road with partial automation systems. Read the entire page →
From page 382... ... 382 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM higher capacity, safety, and possibly speed than normal highway driving, producing substantial impacts in the locations where they are implemented. If dedicated lanes are not provided, the Level 4 automation system capabilities and impacts will be much more limited and it will take significantly longer for them to come to market because of the technical challenges of ensuring their safety in mixed traffic. Read the entire page →
From page 383... ... APPENDIX F 383 continue to include some conventional manually driven vehicles and vehicles with lower levels of driving automation capabilities. These will be used by people who cannot afford the newest vehicles, people who prefer to drive their legacy vehicles, and people who are opposed to highly automated driving for various personal reasons. Read the entire page →
From page 384... ... 384 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM at Level 5 it may be taken completely. Although no explicit safety standards have been specified yet, it is not unreasonable to expect the automated driving system to maintain at least the level of safety of average human drivers today (some observers contend that it is more likely to require 10 times the safety of average human drivers in order to be socially acceptable) Read the entire page →
From page 385... ... APPENDIX F 385 take corrective action (potholes, rocks, or bricks in the path of the vehicle's tires, and so forth) Read the entire page →
From page 386... ... 386 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM ACKNOWLEDGMENT Sections of this report are derived in part from an article, "Connected and Automated Vehicle Systems: Introduction and Overview" by Steven E Shladover, to be published in the Journal of Intelligent Transportation Systems, Date TBD, Copyright Taylor & Francis, available online at http:// dx.doi.org/10.1080/15472450.2017.1336053. Read the entire page →
From page 388... ... 388 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Viegas, J., and L Martinez. Read the entire page →

From page 351...

... Appendix F Connected and Automated Vehicle Technology Impacts on Future Interstate Highway System Steven E Shladover EXECUTIVE SUMMARY This appendix provides an overview of the implications that development and deployment of connected and automated vehicle (CAV)