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Autonomous vehicles are currently a subject of great interest and there is heavy research on creating and improving algorithms for detecting objects in their vicinity. A ROS-based deep learning approach has been developed to detect objects using point cloud data. With encoded raw light detection and ranging (LiDAR) and camera data, several basic statistics such as elevation and density are generated. The system leverages a simple and fast convolutional neural network (CNN) solution for object identification and localization classification and generation of a bounding box to detect vehicles, pedestrians and cyclists was developed. The system is implemented on an Nvidia Jetson TX2 embedded computing platform, the classification and location of the objects are determined by the neural network. Coordinates and other properties of the object are published on to various ROS topics which are then serviced by visualization and data handling routines.

Electric vehicle is increasingly becoming popular and an alternative choice for the consumers because of its environment-friendly operation. Permanent magnet synchronous machines are widely and commonly used as traction motors since they provide higher torque and power density. High torque and power density mean higher current which eventually causes higher temperature rise in the motor. Higher temperature rise directly affects the motor output. Standard tests for UDDS (Urban Dynamometer Driving Schedule) and HWFET (Highway Fuel Economy Driving Schedule) drive cycles are used to determine performance of traction motors in terms of torque, power, efficiency and thermal health. Traction motors require high torque at low speed for starting and climbing; high power at high speed for cruising; wide speed range; a fast torque response; high efficiency over wide torque and speed ranges and high reliability.

In order to define and to optimize a thermal management system for a high voltage vehicular battery, it is essential to understand the environmental factors acting on the battery and their influence on battery life. This paper defines a calendar life aging model for a battery, and applies real world environmental and operating conditions to that model. Charge and usage scenarios are combined with various cooling/heating approaches. This set of scenarios is then applied to the calendar life model, permitting optimization of battery thermal management strategies. Real-world battery life can therefore be maximized, and trade-offs for grid energy conversion efficiency and fuel economy/vehicle range can be determined.

An accurate representation of proving ground loading is essential for nonlinear Finite Element analysis and component fatigue test. In this paper, a rainflow counting based multiple blocks loading development procedure is described. The procedure includes: (1) Rainflow counting analysis to obtain the relationship between load range and cumulative repeats and the statistical relationship between load range and mean load; (2) Formation of preliminary multiple loading blocks with specified load range, mean load, and the approximate cycle repeats, and construction of the preliminary multiple loading blocks; (3) Calibration and finalization of the repeats for preliminary multiple loading blocks according to the equivalent damage rule, meaning that the damage value due to the block loads is equivalent to that from a PG loading.

Environmental concerns and rising fuel costs are driving Ontario's municipalities and fleet operators to consider alternative vehicle technologies. Elevated fuel consumption and air emissions are attributed to the unique operations of fleet vehicles and in particular, during idling. While drivers of passenger vehicles may have the option of simply not idling, fleet and emergency vehicle operators, may need to keep the vehicle operating to supply power to critical onboard equipment. These demands may be exacerbated during seasonal, temperature extremes. However, prolonged idling can impose significant environmental and economic burdens. Hybrid vehicles have yet to be utilized widely by Ontario's fleets, but there are other approaches to reduce emissions, including alternative “green” technologies to operate in-vehicle equipment and maintain fleet vehicle capabilities instead of idling.

This paper proposes and evaluates the use of a robust variable torque distribution (VTD) yaw moment control for an all wheel drive (AWD) hybrid vehicle prototype currently under development. The proposed VTD controller was used to improve the linearity of vehicle response to driver input through the modulation of front-to-rear torque distribution and a corrective torque differential between the left and right rear wheels. The development of a non-linear vehicle model and a reference model tracking sliding mode based control are discussed. The efficacy of the proposed control system was demonstrated through the use of numerical simulations using the developed non-linear vehicle model. The simulation results presented indicate the effectiveness of the proposed system and the potential restrictions to such a system including tire saturation and drivetrain component limitations.

Rollover crash is one of the most serious safety problems for light weight vehicles. In the USA, rollover crashes account for almost one-third of all occupant fatalities in light weight vehicles. Similar statistics are found for other countries. Thus, rollover crashes have received significant attention in recent years. In the USA and Canada, automotive manufacturers are required to comply with the roof strength requirement of “1.5 times the unloaded vehicle weight” to ensure safety in rollover. NHTSA is currently considering a set of countermeasures to improve the rollover safety, where one of the proposals is to increase the roof strength limit to “2.5 times the unloaded vehicle weight”. This increased roof strength limit seemingly has been motivated based on the benchmark study of current vehicle fleet.

Heavy traffic volume makes tailgating a common picture on the road today. Wake interference, particularly in the scenario when a relatively small sedan drives into the wake of a large truck, may raise some serious highway safety concerns. In this paper, the characteristics of the separation bubble of model trucks with various degrees of details are studied. The objective is to find out the impact of truck model details on the characteristics of the wake bubble. Our wind tunnel results revealed that the degree of model detail has a significant effect on the wake bubble; the bubble length increases with model details.

The implementation of fuel cell-battery hybrid vehicles requires a supervisory control strategy that manages the power distribution between the fuel cell and the energy storage device (i.e., battery). Several advanced control methods have already been developed and published in literature. However, most control methods have been developed for different vehicle types and using different mathematical models. The performance of these power management methods have not been directly compared for the same application. This study aims at obtaining direct analytical comparisons, which will provide useful insight in selecting a power management method for fuel cell-battery hybrid vehicles.

This paper talks about using an approach to simulate snow mass falling from roof of cab on the cowl tray of a commercial truck and predicting the durability life of the cowl tray based on this loading. It has always been a challenge for analysts to model the behavior of snow/slurry in dynamic simulations especially where the area of concern is structure and not the fluid. The conventional approach followed in most industries would be either to model snow as soft rubber or to divert from the conventional Lagrangian algorithm for mesh movement towards Eulerian method (or ALE algorithm). Although modeling snow as soft rubber captures the basic physics of the problem, it is not able to correctly simulate the fluid structure interaction behavior and the pressure wave movement inside the snow/slurry when it comes in contact with the structure.

Hybrid Vehicles have gained momentum in the automotive industry. The joint action of power sources and energy storage systems for energizing the vehicle improves the vehicle's fuel economy while reducing its pollutant emissions and noise levels, challenging automotive designers to optimize vehicle's cost, weight and control. The marketing success of hybrid vehicles significantly depends on the selection, integration and cost of the energy systems. The internal combustion engine, dominant of the vehicle market, has been the “option of choice” for auxiliary power unit of the hybrid vehicle, although other power sources as fuel cells, Stirling engines and gas turbines have been employed as well [1]. This document is focused in the application of Stirling engines as the power source for automobile propulsion.

In this study the capabilities of a semi-active suspension and an active roll suspension are evaluated for comparison with a passive suspension. The vehicle used is a utility truck modeled as a multi-body system in ADAMS/Car while the ECU (electronic control unit) is built in Matlab/Simulink. Cosimulation is used in linking the vehicle model with the controller by exchanging the input and output values of each sub-system with one another. For the simulation models considered, results indicate that for a fish-hook cornering maneuver the semi-active suspension is limited in increasing vehicle performance while the active roll suspension significantly improves it. Further analysis is needed to confirm these findings.

A three-pole spark igniter, with the concept to broaden the ignition area, is employed in this paper to investigate the effect of spark discharge strategies on the early ignition burning process. The prototyped three-pole igniter has three independent spark gaps arranged in a triangular pattern with a circumradius of 2.3 mm. Direct-capacitor discharge techniques, utilizing close-coupled capacitors parallel to the spark gap, are applied on the three-pole igniter to enhance either the transient spark power or the overall energy. In particular, the simultaneous discharge of high energy plasma on three spark gaps can produce a surface-like ignition process which intensifies the plasma-flame interaction, thereby producing a rapid flame kernel development. The ignition strategies are evaluated in both constant volume combustion vessels and a modified single-cylinder metal engine.

This paper is the second in the series of documents designed to record the progress of a series of SAE documents - SAE J2836™, J2847, J2931, & J2953 - within the Plug-In Electric Vehicle (PEV) Communication Task Force. This follows the initial paper number 2010-01-0837, and continues with the test and modeling of the various PLC types for utility programs described in J2836/1™ & J2847/1. This also extends the communication to an off-board charger, described in J2836/2™ & J2847/2 and includes reverse energy flow described in J2836/3™ and J2847/3. The initial versions of J2836/1™ and J2847/1 were published early 2010. J2847/1 has now been re-opened to include updates from comments from the National Institute of Standards Technology (NIST) Smart Grid Interoperability Panel (SGIP), Smart Grid Architectural Committee (SGAC) and Cyber Security Working Group committee (SCWG).

Due to their high energy density and low self-discharge rates, lithium-ion batteries are becoming the favored solution for portable electronic devices and electric vehicles. Lithium-Ion batteries require special charging methods that must conform to the battery cells' power limits. Many different charging methods are currently used, some of these methods yield shorter charging times while others yield more charge capacity. This paper compares the constant-current constant-voltage charging method against the time pulsed charging method. Charge capacity, charge time, and cell temperature variations are contrasted. The results allow designers to choose between these two methods and select their parameters to meet the charging needs of various applications.

Contacts or interactions commonly exist between adjacent components in automotive structures, and most of the time they dominate stress status of the components. However, when the routine pseudo stress approach is employed in fatigue life estimations, simulating contacts present special challenges. This may result in coarse stress status and corresponding coarser fatigue life estimations at the contact locations. In this paper, concept, development and procedures of two techniques to consider contacts in fatigue life estimations of automotive structures are described in detail. One is still pseudo stress approach based, but employs additional 1-D connection elements to simulate contacts. The other is nonlinear stress approach based, but equivalent constantly repeating cyclic critical load cases are introduced and utilized. The contacts are simulated by interface setup provided in the software.

With the increased market share of electric vehicles, the demand for energy-efficient routing algorithms specifically optimized for electric vehicles has increased. Traditional routing algorithms are focused on optimizing the shortest distance or the shortest time in finding a path from point A to point B. These traditional methods have been working well for fossil fueled vehicles. Electric vehicles, on the other hand, require different route optimization techniques. Negative edge costs, battery power limits, battery capacity limits, and vehicle parameters that are only available at query time, make the task of electric vehicle routing a challenging problem. In this paper, we present an ant colony based, energy-efficient routing algorithm that is optimized and designed for electric vehicles. Simulation results show improvements in the energy consumption of electric vehicles when applied to a start-to-destination routing problem.

Chrysler, Ford, General Motors, the U.S. Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) have collaborated over the past two years to develop an efficiency test for mobile air conditioner (MAC) systems. Because the effect of efficiency differences between different MAC systems and different technologies is relatively small compared to overall vehicle fuel consumption, quantifying these differences has been challenging. The objective of this program was to develop a single dynamic test procedure that is capable of discerning small efficiency differences, and is generally representative of mobile air conditioner usage in the United States. The test was designed to be conducted in existing test facilities, using existing equipment, and within a sufficiently short time to fit standard test facility scheduling. Representative ambient climate conditions for the U.S. were chosen, as well as other test parameters, and a solar load was included.

The purpose of this study is to determine the feasibility of simulating an active suspension using cosimulation. The vehicle used is a utility truck created in ADAMS/View while the E.C.U. (electronic control unit) is implemented in Simulink for both a fully-active and semi-active controller. The LQR (Linear Quadratic Regulator) is used for the fully-active system while the semi-active system uses a switching law adopted from Karnopp et al. {1}. Nonlinear and linear vehicle models are compared and the influence of suspension bushings is examined. All simulations undertaken are geared towards evaluating the ride capabilities of such systems.

In recent years, bearing electrical failures have been a significant concern in electric cars, restricting electric engine life. This work aims to introduce a coating approach for preventing electrical erosion on 52100 alloy steel samples, the most common material used on manufacturing bearings. This paper discusses the causes of shaft voltage and bearing currents, and summarizes standard electrical bearing failure mechanisms, such as morphological damages and lubrication failures. Alumina coatings are suitable for insulating the 52100 alloy steel samples because alumina coatings provide excellent insulation, hardness, and corrosion resistance, among other characteristics. The common method to coat an insulated alumina coating on the bearing is thermal spraying, but overspray can cause environmental issues, and the coating procedures are costly and time-consuming.