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In heavy duty (HD) trucks cruising on expressway, about 60% of input fuel energy is wasted as losses. So it is important to recover them to improve fuel economy of them. As a waste heat recovery system, a Rankine cycle generating system was selected. And this paper mainly reports it. In this study, engine coolant was determined as main heat source, which collected energies of an engine cooling, an EGR gas and an exhaust gas, for collecting stable energy as much as possible. And the exergy of heat source was raised by increase coolant temperature to 105 deg C. As for improving the system efficiency, saturation temperature difference was expanded by improving performance of heat exchanger and by using high pressure turbine. And a recuperator which exchanges heat in working fluid between expander outlet and evaporator inlet was installed to recover the heat of working fluid at turbine generator. Then a working fluid pump was improved to reduce power consumption of the system.

Cars and trucks today are getting fitted with a large number of sensors in an effort to improve safety, comfort, fuel economy and emissions. The revenue from the automotive sensors market, driven by intense global competition and regulation, is expected to double over the next decade, while the size of the automotive sensors market, over the same period, is expected to triple. The field of sensor-fusion is highly multi-disciplinary, making use of technics from artificial intelligence, pattern recognition, digital signal processing, control theory, and statistical estimation. Sensor-fusion strategies based on probability theory, evidence theory, fuzzy theory, and possibility theory are being explored in different industries, e.g., defense, robotics, automotive, etc. The majority of sensor-fusion operators are based on optimistic assumptions about reliability of the information generated by the sensors.

In order to perform cutting-edge engine research that applies to modern Compression Ignition (CI) engines, a sophisticated test cell is needed that allows control of the engine and its auxiliary systems. The primary obstacle to the completion of such a test cell is the up-front expense. This paper covers the construction of a low cost, single-cylinder engine test cell while demonstrating the type of research that can be accomplished along the way. The components necessary for the construction, instrumentation, and operation of such a test cell, neglecting emissions analysis equipment, can be obtained for less than $150,000. The engine utilized, a naturally-aspirated single-cylinder Yanmar L100V, was purchased as an engine-generator package.

The current certification requirements under CFR 49, Part 567 state that GVWR of a motor vehicle shall not be less than the sum of the unloaded vehicle weight, rated cargo weight and 150 pounds times the number of designated seating positions. Actual occupant weight distributions versus certified weight per occupant seat causes a potential conflict between a vehicle's in-use weights versus its certified GVWR. Population weight distributions were developed based upon The Center for Disease Control's (CDC) publication of 2007 - 2010 anthropometric reference data and publically available weights of a special population from high school football teams. For five buses from small (18-seat) to large (55-seat), key parameters were measured.

For passenger cars, individual tyre model parameters, used in vehicle models able to simulate vehicle handling behavior, are traditionally derived from expensive component indoor laboratory tests as a result of an identification procedure minimizing the error with respect to force and slip measurements. Indoor experiments on agricultural tyres are instead more challenging and thus generally not performed due to tyre size and applied forces. However, the knowledge of their handling characteristics is becoming more and more important since in the next few years, all agricultural vehicles are expected to run on ordinary asphalt roads at a speed of 80km/h. The present paper presents a methodology to identify agricultural tyres' handling characteristics based only on the measurements carried out on board vehicle (vehicle sideslip angle, yaw rate, lateral acceleration, speed and steer angle) during standard handling maneuvers (step-steers, J-turns, etc.), instead than during indoor tests.

In order to reasonably match the variable stiffness suspension and optimize the ride comfort and stability of a light bus, a virtual prototype model of the light bus was established in Adams-Car. Before the optimization, the tyre mechanical characteristics were tested by using a plate-type tyre tester, then the magic formula model of the tyre (Pac2002) was obtained by means of the global parameter identification method. The vertical vibration of the virtual model was simulated with the simulated B-class road profile, and its handling stability performance was also studied by simulation of the pylon course slalom test and steady static circular test. After that, an optimal method of the variable stiffness suspension was put forward. In the proposed method, the two-level stiffness (k1, k2) and the damping of the rear suspension and the torsional stiffness of the pre and post stabilizer bars were taken as the optimal variables.

Driver is a key component in vehicle simulation. An ideal driver model simulates driving patterns a human driver may perform to negotiate road profiles. There are simulation packages having the capability to simulate driver behavior. However, it is rarely documented how they work with road profiles. This paper proposes a new truck driver model for vehicle simulation to imitate actual driving behavior in negotiating road grade and curvature. The proposed model is developed based upon Gipps' car-following model. Road grade and curvature were not considered in the original Gipps' model although it is based directly on driver behavior and expectancy for vehicles in a stream of traffic. New parameters are introduced to capture drivers' choice of desired speeds that they intend to use in order to negotiating road grade and curvature simultaneously. With the new parameters, the proposed model can emulate behaviors like uphill preparation for different truck drivers.

The rigid-ring tire model is a simplified tire model that describes a tire's behaviour under known conditions through various in-plane and out-of-plane parameters. The complex structure of the tire model is simplified into a spring-mass-damper system and can have its behaviour parameterized using principles of mechanical vibrations. By designing non-linear simulations of the tire model in specific situations, these parameters can be determined. They include, but are not limited to, the cornering stiffness, vertical damping constants, self-aligning torque stiffness and relaxation length. In addition, off-road parameters can be determined using similar methods to parameterize the tire model's behaviour in soft soils. By using Finite Element Analysis (FEA) modeling methods, validated soil models are introduced to the simulations to find additional soft soil parameters.

Heavy duty tractor-trailers under freeway operations consume about 65% of the total engine shaft energy to overcome aerodynamic drag force. Vehicles are exposed to on-road crosswinds which cause change in pressure distribution with a relative wind speed and yaw angle. The objective of this study was to analyze the drag losses as a function of on-road wind conditions, on-road vehicle position and trajectory. Using coefficient of drag (CD) data available from a study conducted at NASA Ames, Geographical Information Systems model, time-varying weather data and road data, a generic model was built to identify the yaw angles and the relative magnitude of wind speed on a given route over a given time period. A region-based analysis was conducted for a study on interstate trucking operation by employing I-79 running through West Virginia as a case study by initiating a run starting at 12am, 03/03/2012 out to 12am, 03/05/2012.

The large power mining dump truck usually has electric drive system for the harsh operating conditions of mining. The traction motor and multi-stage reducer are assembled in the limited space of the two rear wheels. The permanent magnet motor is often used as traction motor for its much advantage characteristic. However, the permanent magnet is particularly sensitive to the high temperatures since it can loose a part of magnetization when it is exposed to a high temperature. It is necessary to have better cooling system for improvement thermal performance of permanent magnet (PM) motor. The heat losses generated by permanent magnet motor in the off-road electric driving truck are cooled by the water to maintain the motor working effectively. This paper is focus on analyzing the thermal behavior of the PM motor numerically and experimentally.

The work investigates the integration between tools for analysis and simulation of cooling systems at Volvo Group Trucks Technology. At the same time it is a consequent step in evaluating GT-SUITE for the purposes of analysis and simulation of such systems. The focus is on 1D simulation tools, which are generally preferred in the context of transient simulations of engine and power train installation systems. The Cooling Analysis and Simulations group at Volvo Group Trucks Technology use a variety of 1D simulation tools for analysis of cooling performance. Volvo Power Train, on the other hand, use among others GT-SUITE for engine simulations. It is expected to improve the quality of the simulation, (i.e the accuracy of the results) and improve system integration by using one tool for both areas of simulation. This work delivers two transient models of FH 13L cooling system integrated with a predictive model of the engine and a detailed model of the main coolant circuit.

Dual loop EGR systems (having both a high pressure loop EGR and a low pressure loop EGR) have been successfully applied to multiple light-duty diesel engines to meet Tier 2 Bin 5 and Euro 5/6 emissions regulations [1, 2], including the 2009 model year VW Jetta 2.0TDI. Hyundai and Toyota also published their studies with dual loop EGR systems [3, 4]. More interest exists on the low pressure loop EGR effects on medium to heavy duty applications [5]. Since the duty cycles of light duty diesel and heavy duty diesel applications are very different, how to apply the dual loop EGR systems to heavy duty applications and understanding their limitations are less documented and published. As a specific type of heavy duty application, this paper studied the dual loop EGR effects on the retrofit applications of heavy duty diesel for delivery and drayage applications. The reduction of NOx emissions and the impact on fuel economy and controls are discussed.

Vehicle-to-vehicle (V2V) communication is an important part of intelligent transportation system. With the vigorous development of expressway construction, it is of great significance to study the propagation characteristics of V2V communication channels in the scene of expressway under construction. This paper describes in detail the V2V broadband channel measurement activity carried out on the A96 expressway in the suburb of Munich, Germany. Based on the measured data, the variation of signal receiving power while the vehicle was moving is analyzed. We focus on the small-scale fading characteristics of expressway sections under construction in the C-band. The results show that the magnitude of received signal varies rapidly while vehicles are moving. Comparing the measurement data with theoretical distributions, it has been found that the magnitudes of measurement data on the expressway under construction fit the best to the Rice distribution.

In order to solve the problem of road traffic congestion in urban central area, this paper explores the influence of different bus lanes on traffic operation. In this paper, the detector will be used to identify the operation status of public transport vehicles in real time, and traffic data will be obtained by bayonet electronic police, RFID, GPS, baidu map and field volume, including road layout, intersection distribution, public transport facilities, roadside parking, etc., as well as the distribution of infrastructure such as intersection signal timing scheme and bus priority signal timing. Finally, taking the intersection group of Qianjin Road and Changjiang Road in Kunshan City as an example, VISSIM simulation is carried out from three locations of right turn lane bus only entrance lane, through lane bus only entrance road and left turn lane bus only entrance road, and explores the optimization scheme.

This paper clarified the dynamic impact of automated bus on asphalt pavement by taking an innovative bus using automation technology as a case study. Firstly, main distresses caused by automated bus on roads were investigated. On this basis, a three-dimensional finite element model that considers the vehicle type and driving conditions of automatic bus was established.

In order to study the influence of autonomous vehicles on short and medium distance mode choice for intercity travel, this paper incorporates the latent psychological variables that affect the choice behavior of autonomous vehicles into the latent class conditional logit model and establishes a hybrid choice model to conduct the empirical research based on the theory of planned behavior. The results show that compared with the traditional multinomial logit model, the latent class conditional logit model has higher fitting goodness. Travelers can be divided into three subgroups: class1, class2, and class 3, accounting for 40.7%, 24.4%, and 34.9%, respectively. At a 5% confidence level, gender, education, occupation, monthly household income, children, and IC card significantly affect the sample’s latent class.

Currently, most of vehicle recognition methods are realized by deep convolutional neural networks (DCNNs) with input of images directly as training data. Due to the factor of perspective distortion and scale change of images taken by monocular camera, a large number of multi-scale images need to be used for training, and physical information of vehicles cannot be obtained at the same time. In order to improve the above problems, we present a method of vehicle recognition based on unpacking 3D bounding boxes in this paper. Firstly, camera calibration information and geometric constraints are used to build 3D bounding boxes around vehicles in monocular projection. Then, the 3D bounding boxes are unpacked to obtain 3D normalized spatial data without perspective distortion. Finally, VGG-16 is chosen as the backbone of our network, the output of which can be divided into five common vehicle types including hatchback, sedan, SUV, truck and bus.

With the development of cooperative vehicle and infrastructure automatic driving technology, the intelligence degree of vehicles continues to increase, and the road traffic environment will transition from a single manual driving to a mixed transition of multiple control strategies. Compared with the conventional traffic flow, the traffic flow with multiple control strategies coexisting under the cooperative vehicle infrastructure system shows kinds of different characteristics. With the increasing participation of the autonomous vehicles in public transportation, a key point is the impact of autonomously driven vehicles on the driving environment. In order to analyze this problem more thoroughly, we selected the common bottleneck point of urban roads on-line bus stops as the research scenario, analyzed the impact of bus stops on traffic flow in a cooperative vehicle and infrastructure system furtherly.

The inherent attributes of production tools for commercial vehicle determine that have more needs and applicability for autonomous driving technology. The port is one of the three core scenarios for application of autonomous driving of commercial vehicle. Port transportation is regarded as an important aspect of commercial vehicle autonomous driving applications by governments, enterprises and port managers [1]. Currently port autonomous driving applications have a good policy environment and market environment. First of all, this paper introduces the main types and distribution patterns of port autonomous driving applications by analysis its current status both at home and abroad. Secondly, through the characteristic analysis of each application mode, IGV mode is determined to be the first choice for smart port reconstruction due to its advantages of time-consuming and low-cost based on the comparison of the current application modes.

With the increase in the number of cars in cities, traffic jams occur frequently, especially between upstream stops and intersections. As a means of transportation, public transport can effectively improve the efficiency of travel. However, the current research on the optimization of bus priority signal timing at intersections does not systematically consider the impact of the upstream bus stops at the intersection. In this regard, the article starts from the impact of upstream bus stops on the priority control of intersections, uses total passenger delay as the control standard, and builds an intersection bus priority signal timing model that considers the influence of upstream stops to extend the time by optimizing the green light to achieve the optimization of the bus priority signal timing scheme at the intersection.