This report defines an architecture for Automated Highway System (AHS) capacity-optimizing traffic planning functions. It identifies major traffic planning functions useful for optimizing the capacity of one or more major AHS operating scenarios and organizes them in a robust architecture that is modular, hierarchical, complete, expandable and integratable.

California would be the seventh largest economy in the world, if it were a nation. Efficient goods movement is crucial to California's economy. To support continued growth of the State's economy, Caltrans is leading the development of a Statewide Goods Movement Strategy. This strategy is being prepared as a response to a recommendation of the 1993 California Transportation Plan. It serves as one element, together with the Transportation System Performance Measures report being prepared in parallel by Caltrans, of the 1998 California Transportation Plan update. Air cargo consists predominantly of high-value, time-sensitive or time-definite goods, e.g., electronic equipment, emergency shipments, overnight packages, etc. Timely delivery of these goods has been an important element of many manufacturing and service operations in California. Therefore, the air cargo industry is a vital part of the State's economy. Continued ability of the State's air cargo industry to serve the other industries in the State and the State's ability to capitalize on the forecast growth of air cargo routes between Pacific-Rim countries in Asia and North America are essential to the prosperity of California. However, future demand on California's air cargo system may continue to outpace the future supply of the system's capacity. Faced with these challenges, Caltrans began a systematic investigation into the role of air cargo in California's goods movement, as part of the larger development effort for a statewide goods movement strategy, and funded a research project in 1997 for the Institute of Transportation Studies at U.C. Berkeley to (i) gain a broader understanding of the State's air cargo industry and the role of air cargo in California's goods movement, (ii) assess the importance of air cargo to the State's economy, (iii) begin identification of issues hindering efficient air cargo movement in the State, and (iv) explore possible State roles for resolving the issues. This "white paper" documents the findings of that research and serves as an input to the development of the Statewide Goods Movement Strategy.

This paper proposes a shuttle van service as the initial deployment Automated Highway System (AHS) target. The freeway portion of the trip is fully automated and a professional driver is required for off-freeway driving. Advantages from the viewpoint of of different deployment issues are discussed. Focus is on the concept definition.

This paper proposes an approach to defining evolutionary scenarios for the deployment of an Automated Highway System (AHS). Six dimensions of deployment difficulties are identified: technology, infrastructure, human factors, vehicle manufacturing and maintenance, insurance, and public will.

Traffic congestion has been a pervasive problem in many urban areas of this country. This paper studies the potential of carpooling among unrelated partners (i.e., inter-household carpooling) for demand reduction during peak commute hours. Basic questions about this potential include the following. Can the current population density, origin-destination distribution, tolerable pick-up and drop-off delays, departure time distribution, and the tolerance for deviation from preferred departure time support a sizable carpooling population that can make a significant contribution to traffic demand reduction? Could the proportion of long trips that are likely candidates for carpooling (e.g., those long trips with same O-D) be so small that no significant traffic demand reduction could be expected from carpooling? The potential depends on many factors, some of which are more amenable to quantification than others. Our approach to assessing the potential is to separate such quantifiable factors from the rest, and then, based on these quantifiable factors, identify likely upper bounds for the potential. This paper focuses on a simplified urban sprawl in which the densities of workers and jobs are uniform over an infinitely large flat geographical area. For our numerical study, we use the job and worker data of the city of Los Angeles to approximate the worker/job density. An entropy optimization model that is equivalent to the gravity model is used for trip distribution. Under the assumptions made in the paper, carpooling among unrelated partners has little potential for demand reduction. Key Words: Carpool, Demand Management, Urban Sprawl, Trip Distribution, Entropy Optimization

This research has four main purposes: 1. Investigate and suggest how the public sector in the state of California (including the state, cities, counties, airports, etc.) can assist the air cargo industry in providing more efficient services to businesses and the general public of California. 2. Learn from the air cargo industry's efficient intermodal operations about intermodal freight and passenger transportation in general. 3. Learn from the industry's technology deployment efforts for the purpose of developing strategies for deploying Intelligent Transportation Systems (ITS) technologies in the general freight industry and in the overall transportation industry. 4. Suggest ITS deployment strategies for other segments of the freight industry.

What some human drivers have done wrong has been blamed for much of the problem associated with the current highway systems. For example, driver inattention, fatigue and other human errors have often been cited as major sources of safety hazard on current highways and human capabilities as major limitations on current highway capacity. Such human deficiencies and the pervasive urban traffic congestion have motivated the concept of Automated Highway Systems (AHS). The fundamental objective of AHS is to achieve user and societal benefits through replacing human driving by automated machine driving. The first fundamental thesis of this paper is that safe replacement of human driving on highways by automation requires a rigorous examination into what most human drivers have been doing right on the current highway systems. Such an examination would provide much insight into the functional requirements for AHS, i.e., what machines must do to emulate or improve human driving. Furthermore, what human drivers tend to do poorly or well must be contrasted with what machines tend to do well or poorly. A complementary arrangement must be sought if the machines cannot safely or affordably replace driver intelligence for highway driving, either on a mature AHS or during intermediate stages toward it.

Driving tasks involved in any vehicle-roadway system depend on the driving environment. For example, city-street driving is different from driving on current highways and AHS driving may be drastically different from current highway driving. On an AHS, any human intelligence required by current highway driving must be replaced (emulated or improved) by machine intelligence or continues to be provided by the driver, if proven safe, unless the corresponding tasks are eliminated from AHS driving due to the environment change. Note that new driving environments may introduce new driving tasks. Since the driving environment during early deployment stages of AHS is likely identical to that of the current highways, most, if not all, of the current highway-driving tasks remain necessary. The second fundamental thesis of this paper is that current highway driving involves not only many routine chores, which machines tend to do well, but also much human intelligence, which machines tend to do poorly. Such intelligence is often required in subtle ways or is required only when unusual but normal events occur. We identify many such driving functions. If some of these required functions cannot be safely emulated by machines either in a mature end-state AHS or during intermediate stages toward the end state, then "driver-in-the-loop'' must not be ruled out at the current research and development stage.

This paper develops a probabilistic model and a software tool for analyzing longitudinal collision/safety between two automated vehicles. The input parameters are the length of the gap between the two vehicles, the common speed prior to failure, the reaction delay of the following vehicle and a bivariate joint distribution of the deceleration rates of the two vehicles. The output includes the probability of a collision and also the probability distribution of the relative speed at collision time. The model is used to compare the safety consequences associated with the platooning and "free-agent" vehicle-following rules. Additionally, it is demonstrated that the free-agent vehicle-following rule implemented with a potential technology of fast and accurate emergency deceleration, under some reasonable conditions, can virtually avoid collisions while offering a high freeway capacity previously through possible only under the platooning rule.