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Heavy duty truck mechanical configuration is often tailor designed and built for specific truck mission requirements. This renders the precise derivation of analytical dynamical models and controls for these trucks from first principles challenging, tedious, and often requires several theoretical and applied areas of expertise to carry through. This article investigates deep learning and deep reinforcement learning as truck-configuration-agnostic longitudinal modeling and control approaches for heavy duty trucks. The article outlines a process to develop and validate such models and controllers and highlights relevant practical considerations. The process is applied to simulation and real-full size trucks for validation and experimental performance evaluation. The results presented demonstrate applicability of this approach to trucks of multiple configurations; models generated were accurate for control development purposes both in simulation and the field.

Connected Automated Vehicles (CAVs) are similar to other automated vehicles with the distinguishing difference being that CAVs obtain information about road conditionsdirectly from other vehicles and infrastructure (e.g., traffic signals, road sensors) rather than relying solely on onboard sensors. Different CAV technologies are currently being tested and evaluated to assess the prospects for future implementation. These tests involve moving CAV-equipped vehicles on a physical test track and recording how the vehicles operate under different traffic conditions (Figure 1). Since it is difficult and expensive to recreate multiple real-world driving conditions on a single test track, virtual environments are typically used to simulate different traffic conditions, such as traffic signal operation, actions by other vehicles on the road, and other scenarios. These virtual hardware-in-the-loop (HIL) tests can expedite CAV performance evaluation and inform future system implementation; however, existing HIL test systems often lack the ability to manage large amounts of test data, which limits the value and use of these tests.

Traffic congestion and trucking activities in the San Francisco Bay Area are increasing due to the rapid population growth and economic expansion. It is imperative to explore transportation alternatives, and the Bay Area Rapid Transit (BART) system, with 63 percent unused capacity on average in non-peak hours, presents such an opportunity. If BART’s service is extended to include air-freight movement, extra revenue can be generated, truck miles travelled on highways will be reduced (potentially leading to a reduced traffic congestion and pollution), and traffic safety could be improved. The objective of this study is to identify the number of feasible dedicated freight train that can be accommodated by BART lines using its current operational schedule, without creating a negative effect on passenger service. The measurement of time or distance between two successive train-runs at a station, also referred to as the ‘headway’, for selected lines have been considered to evaluate possible freight train insertions into time-space slots of current passenger services. To qualify this, the headway of the two trains needs to be greater than twice the minimum headway required (based on BART train safety requirements). Furthermore, BART trains should be subjected to the limit on acceleration/deceleration capabilities. The findings are as follows: for peak hours and commute directions, it would be impracticable to add more trains. For peak hours in non-commute directions, some capacity could exist for mixed freight cars and on empty passenger cars. For non-peak periods such as early mornings and evenings, slots for dedicated freight train insertions are available.

The work reported here includes the development of the underlying theory for detecting traffic flow breakdown at a bottleneck and for defining the speed profiles that vehicles should be following in order to maximize the flow through the bottleneck region. It also includes a preliminary test of the communication of the variable speed limit values to an instrumented vehicle for display to drivers from the general public, in order to determine their reactions to the variable speed limits. The selection of variable speed limits (VSL) to reduce traffic breakdowns is based on careful modeling of the traffic dynamics and estimation of the probability of breakdown as a function of traffic speed and density. The VSL values chosen by the algorithm developed here were broadcast to a test vehicle driven along the I-80 corridor by 16 drivers from the general public, and their reactions to the VSL information were captured by recording data about their driving behavior and collecting their responses to a questionnaire. These results indicated that although the VSL concept is very promising, the implementation needs to provide for better filtering of noisy and inconsistent data so that drivers receive a display of VSL values that are stable in location and time and appear believable to the drivers.

This report examines the impact and feasibility of using urban railway system for freight movement. In particular, using the Bay Area Rapid Transit (BART) system for FedEx Express air cargo movement is analyzed as a case study. Based on the framework constructed in the study of last phase, social impact (externalities), reliability, and infrastructure feasibility are considered. The social cost related to emission, energy consumption/efficiency, impact on road traffic and land use is considered. The reliability issue is examined from two aspects: transportation delay, and emergency situation handling. The infrastructure feasibility is analyzed based on the proximity and accessibility of BART yards/shops/stations and FedEx collection/distribution centers, the air freight container size, and the conceptual designs of dedicated BART freight car and transshipment equipment.

Embroidery is the unique language of Miao people and a special carrier of culture and art of Miao. Miao embroidery is fabulous in design and rich in pattern. This paper intends to help people to appreciate the particular charisma of decoration art of Miao by examining the origin, style, pattern language form and cultural connotation of Miao embroidery in Hunan and Guizhou province, and penetrating into the artistic language of Miao and its taste.

This report describes the concept of operations for the three mobility applications that PATH is developing and evaluating under the sponsorship of the FHWA Exploratory Advanced Research Program. These applications are intended to use DSRC wireless communications among vehicles and between vehicles and the roadway infrastructure to improve mobility on limited-access highways. The first application combines ramp metering with variable speed limits to enhance control of traffic so that traffic flow breakdowns can be deferred or avoided at bottleneck locations. The second application uses vehicle-vehicle communication to improve the performance of adaptive cruise control systems so that they can operate safely with smaller longitudinal gaps and vehicle-roadside communication to provide adjustments to their set speed and gap settings to adapt to changes in local traffic conditions. The third application uses vehicle-vehicle communication to enable three tractor-trailer trucks to drive in a coordinated platoon at short enough gaps that they can substantially reduce their aerodynamic drag and increase the effective capacity of their lane.

This working paper has been prepared as part of research to develop a combined quantitative and qualitative approach to planning for improved intermodal connectivity at California airports. The quantitative approach involves the development of an Intermodal Airport Ground Access Planning Tool that combines an air passenger model choice model, a model of transportation provider behavior and a traffic network analysis model. The qualitative approach will be used to enhance the quantitative analysis to account for those factors which are difficult to quantify and to provide recommended policy and planning guidelines.

This project studies the coordination layer control and decision making for automated trucks and buses. Maneuver design and coordination algorithms need to take several factors into consideration. Practical achievement in this project includes the following: automated ground vehicle maneuver coordination; maneuver design for automated trucks/buses; model-based simulation package development for control design and real-time code development.Â

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Keywords longitudinal control, car platooning, back-stepping control, multi-surface dynamic sliding mode control, integral filters, realtime control code This report presents the development of nonlinear longitudinal controllers and their realtime implementation for Automated Highway Systems (AHS) at PATH, U. C. Berkeley supported by the project MOU 331. The demo'97 realtime code was first reconstructed for further development. Based on the new framework, the implementation and comparison of nonlinear controllers in the longitudinal control for cars platooning and other maneuvers have been carried out. Specifically, a dynamic sliding mode controller and a dynamic back-stepping multiple surface controller have been implemented, which are then compared to the previously implemented adaptive sliding mode controller. In the dynamic back-stepping control, a new type of integral filters have been developed, which were used for filtering measured signals and to estimate the derivative of these signals in realtime. These controllers have been implemented in realtime code and tested at low and high speed. Realtime run shows that each controller has its own characteristics. In general, the optimal dynamic back-stepping sliding surface controller has better performance by using the same set of measured data compared to previously implemented adaptive sliding mode controller. Emphasis has been put on the dynamic back-stepping multiple surface controller development.

This report presents the work on the development of the regulation layer for automated merging. It includes system modeling, control system synthesis, theoretical analysis and real-rime implementation and field test. The essential part is a rather general adaptive merging algorithm. Key words: automated highway systems, advanced vehicle merging maneuvers, automated vehicle merging maneuvers, longitudinal control, speed control, distance control, vehicle platooning, virtual platooning, adaptive realtime merging algorithm, back-stepping control, magnet distance measurement