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Traffic Control Strategies for Congested Heterogeneous Multi-Vehicle Networks

University of North Carolina Charlotte-Pouria Karimi Shahri, Amir H. Ghasemi, Vahid Izadi
  • Technical Paper
  • 2020-01-0086
To be published on 2020-04-14 by SAE International in United States
The primary goal of this paper is to pioneer and develop robust and adaptive algorithms for controlling autonomous vehicles in heterogeneous networks with the aim of maximizing the performance (in terms of mobility) and minimizing variation in the network. While the fundamental approaches and models proposed in this research can be applied to any heterogeneous multi-agent system, we select heterogeneous traffic networks as a set-up for exploring the proposed research. We consider the heterogeneity in the system in the form of a mix of autonomous and human-driven vehicles (different levels of autonomous vehicle penetration). We propose a two-level hierarchical controller wherein the upper-level controller, an optimization problem using the concept of macroscopic fundamental diagram is formulated to deal with the traffic demand balance problem. At the lower level, using the microscopic models of the network, the control actions for each vehicle will be determined such that he optimal flow received from the upper-level controllers can be tracked.
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The Review of Vehicle Purchase Restriction in China

Tsinghua University-Feiqi Liu, Han Hao, Fuquan Zhao, Zongwei Liu
  • Technical Paper
  • 2020-01-0972
To be published on 2020-04-14 by SAE International in United States
In the past two decades, rapidly expanding economy in China led to burst in travel demand and pursuit of quality of life. It further promoted the rapid growth of China's passenger car market. China had already become the largest vehicle sales country, exceeding the U.S. in 2010. By the end of 2018, there had been over 240 million cars in China, with over 200 million passenger cars. The surge of car ownership has also brought a series of problems, like traffic congestion, long commuting time, insufficient parking space, etc. Therefore, some local governments in China introduced vehicle purchase restriction policies to control the growth and gross of vehicle stock. Different cities issued different rules. Lottery and auction mechanisms both exist. There are also differences in classification and licensing of electric vehicles. While, With the recent slowdown of economic development, China's car sales began to decline in 2018, and the trend of 2019 is also not optimistic. As a result, the central government issued document, indicating that it is strictly forbidden to introduce new restrictions on…
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Experimental ride comfort analysis of an electric light vehicle in urban scenario

Politecnico di Torino-Angelo Domenico Vella, Alessandro Vigliani, Antonio Tota, Domenico Lisitano
  • Technical Paper
  • 2020-01-1086
To be published on 2020-04-14 by SAE International in United States
Urban mobility represents one of the most relevant global challenges which the world has to face up in the next few years. Traffic congestion regulation, pollution level abatement and global warming reduction are concrete issues which will unavoidably influence many aspects of human life. Within this context, in continuous and fast evolution, several options regarding vehicle design and power sources technologies are developing: among them, electric and hybrid vehicles are quite successful to meet the increasing restrictive environmental targets. On the other hand, this significant goal may affect the perceived vehicle comfort and drivability, especially in everyday urban scenarios. In this framework, European project STEVE is aimed to demonstrate urban sustainable co-mobility obtained by light electric vehicles. The purpose of this paper is to carry out a comparison in terms of comfort between two vehicles belonging to different segments, but both designed for urban mobility: a STEVE electric quadricycle and a conventional combustion engine passenger car. Experimental tests are carried out in order to acquire vertical accelerations on board driving ON different road surfaces at…
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Creating Driving Scenarios from Recorded Vehicle Data for Validating Lane Centering System in Highway Traffic

General Motors LLC-Gabriel Choi, Paul Adam
The MathWorks, Inc.-Seo-Wook Park, Kunal Patil, Will Wilson, Mark Corless
  • Technical Paper
  • 2020-01-0718
To be published on 2020-04-14 by SAE International in United States
Traffic Jam Assist system helps the driver to follow the preceding vehicle automatically with a predefined time interval in a dense traffic condition while controlling steering for keeping the current lane. This requires a combination of longitudinal control with adaptive cruise control with stop & go and lateral control with lane following control. In order to validate the performance of the automated driving system, it normally requires tens of thousands of miles of driving the vehicle on the road. This is a time-consuming process and adoption of the virtual simulation tool is inevitable to reduce the development time and enhance the robustness. The challenge is how to preciously reproduce the real-world driving scenarios with the virtual driving environment. This paper introduces a workflow to create the driving scenarios from HERE HD map. The HERE HD map provides the road and lane information for the recorded GPS data. MathWorks Automated Driving toolbox™ is used to create the driving scenario based on the extracted road network information. The ego and non-ego vehicles are added to the driving…
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Deep Learning-based Queue-aware Eco-Approach and Departure system for Plug-in Hybrid Electric Bus at signalized intersections: a simulation study

Oak Ridge National Laboratory-Zhiming Gao, Tim LaClair
University of California-Fei Ye, Peng Hao, Guoyuan Wu, Danial Esaid, Kanok Boriboonsomsin, Matthew Barth
  • Technical Paper
  • 2020-01-0584
To be published on 2020-04-14 by SAE International in United States
Eco-Approach and Departure (EAD) has been considered as a promising eco-driving strategy for vehicles traveling in an urban environment, where signal phase and timing (SPaT) and geometric intersection description (GID) information are well utilized to guide the vehicles passing through the intersection in a most energy efficient manner. Previous studies by the authors formulated the optimal trajectory planning problem as finding the shortest path on a graph model where the nodes define the reachable states of the host vehicle (e.g., speed, location) at each time step, the links govern the state reachability from previous time step, and the link costs represent the energy consumption rate due to state transition. This method is effective in energy saving, but its computation efficiency can be enhanced by machine learning techniques. In this paper, we propose an innovative Deep Learning-based Queue-aware Eco-Approach and Departure (DLQ-EAD) System for a Plug-in Hybrid Electric Bus (PHEB), to provide an online optimal vehicle trajectory considering both the downstream traffic conditions (i.e. traffic lights, queues) and vehicle powertrain efficiency. Based on the optimal solutions…
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Effects of Injection Pressure, Intake throttling, and Cylinder Deactivation on Fuel Consumption and Emissions for a Light Duty Diesel Engine at Idle Conditions

University of Texas-Meng Lyu, Yousif Alsulaiman, Corey Tambasco, Matthew Hall, Ron Matthews
  • Technical Paper
  • 2020-01-0303
To be published on 2020-04-14 by SAE International in United States
The continuing growth of urban population centers has led to increased traffic congestion for which vehicles can spend considerable periods at low speed/low load and idle conditions. For light-duty Diesel vehicles, these low load conditions are characterized by low engine exhaust temperatures (~100oC). Exhaust temperatures can be too low to maintain the activity of the catalytic exhaust aftertreatment devices (usually need >~200oC) which can lead to high emissions that contribute to deteriorating urban air quality. This study is a follow on to two previous studies on the effects of throttling, post-injection, and cylinder deactivation (CDA) on light-duty Diesel engine exhaust temperatures and emissions. The focus of the present study is on fuel consumption and emissions with and without cylinder deactivation and the sensitivity to or effects of fuel rail pressure, along with observations of apparent idle engine friction. The baseline injection strategy was adapted from a 2014 Chevrolet Cruze having an engine similar to the light-duty 2.0 liter GM engine used for this study. All measurements were made under idle conditions and with the engine…
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The Effects of Varying Penetration Rates of L4-L5 Autonomous Vehicles on Fuel Efficiency and Mobility of Traffic Networks

Ohio State University-Ozgenur Kavas-Torris, Mustafa Ridvan Cantas, Karina Meneses Cime, Bilin Aksun Guvenc, Levent Guvenc
  • Technical Paper
  • 2020-01-0137
To be published on 2020-04-14 by SAE International in United States
With the current drive of automotive and technology companies towards producing vehicles with higher levels of autonomy, it is inevitable that there will be an increasing number of SAE level L4-L5 autonomous vehicles (AVs) on roadways in the near future. The effect of this gradually increasing penetration of AVs on mobility, viewed as traffic congestion or traffic flow efficiency in this paper, and fuel efficiency improvement for the individual AV and for the whole road network with a mixed traffic of AVs and non-AVs is currently not well known. Microscopic traffic simulators that simulate realistic traffic flow are crucial in studying, understanding and evaluating the possible effects of having a higher number of autonomous vehicles (AVs) in traffic under realistic mixed traffic conditions including both autonomous and non-autonomous vehicles. In this paper, L4-L5 AVs with varying penetration rates in total traffic flow were simulated using the microscopic traffic simulator Vissim on urban, mixed and freeway roadways to study the effect of penetration rate on fuel consumption and efficiency of traffic flow. The roadways used in…
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Towards Design of Sustainable Smart Mobility Services through a Cloud Platform

Ford Motor Company-Dominique Meroux, Cassandra Telenko, Zhen Jiang, Yan Fu
  • Technical Paper
  • 2020-01-1048
To be published on 2020-04-14 by SAE International in United States
People and their communities are looking for transportation solutions that reduce travel time, improve well-being and accessibility, and reduce emissions and traffic congestion. Although new mobility services like ridesharing advertise improvements in these areas, closer inspection has revealed a discrepancy between industry claims and reality. Mobility service providers have the opportunity to leverage connected vehicle and connected device data through cloud-based APIs. We propose a CO2 data analytics framework that functions on top of a cloud platform to provide unique system-level perspectives on operating transportation services, from procuring the most environmentally and people friendly vehicles to scheduling and designing the services based on data insights. The motivation behind such an approach is two-fold: first, quantification enables transparency to build trust between the mobility service provider and their constituent communities; and second, identifying and acting to improve sustainability improves profitability. Using a benchmark problem with real-world vehicle and mobile device data, we demonstrate the functionality of our CO2 analytics framework.
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VIRTUAL METHOD FOR ELECTRONIC STOP-START SIMULATION & VDV PREDICTION USING MODIFIED DISCRETE SIGNAL PROCESSING FOR SHORT TIME SIGNALS

FCA US LLC-Abhishek Paul, Jaspreet Kukreja, Syed Haider
HBM Prenscia-Joe Spadola
  • Technical Paper
  • 2020-01-1270
To be published on 2020-04-14 by SAE International in United States
Electronic Stop-Start (ESS) system automatically stops and restarts the engine to save energy, improve fuel consumption and reduce emissions when the vehicle is stationary during traffic lights, traffic jams etc. The start and stop events cause unwanted vibrations at the seat track which induce discomfort to the drivers and passengers in the vehicle. These events are very short duration events, usually taking less than a second. Time domain analysis can help in simulating this event but it is difficult to see modal interactions and root cause issues. Modal transient analysis also poses a limitation on defining frequency dependent stiffness and damping for multiple mounts. This leads to inaccuracy in capturing mount behavior at different frequencies. Most efficient way to simulate this event would be by frequency response analysis using modal superposition method. In order to do the same there is a major hurdle which is due to the nature of the signal being highly transient and of short duration, this event is difficult to be captured in frequency domain. Traditional FFT techniques used for domain…
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Proposed Model to Implement a Blockchain for Secure Vehicle to Vehicle Communication

General Motors Technical Center India-Surya P. Palavalasa
  • Technical Paper
  • 2019-28-2433
Published 2019-11-21 by SAE International in United States
This paper proposes a model to implement a blockchain network that can host a system of autonomous vehicles which communicate through generic V2V protocols like DSRC and CV2X. The blockchain will be designed to function like a global database for V2V communication. The purpose behind the proposal of this model was to ensure a transparent and secure network between all autonomous vehicles which indirectly leads to reduced traffic congestion and takes us a step closer to zero crashes. This is made possible by the blockchain ledger’s enhanced encryption systems.
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