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Braking Performance of the One Side Wheels for the Realization of the Crab Motion for the Front-Wheel Vehicle

Kharkov National Auto and Highway University-Mikhail Podrigalo, Dmytro Klets, Oleksandr Boboshko
National Academy of National Guard of Ukraine-Ruslan Kaidalov, Andrey Nikorchuk, Maxim Adamchuk, Ihor Luhovskyi, Oleksandr Bilenko, Oleksandr Kriukov, Yuri Besedin
  • Technical Paper
  • 2019-01-2147
To be published on 2019-09-15 by SAE International in United States
A method of vehicle straight angle motion relative its axial axis by turning the front wheels and simultaneous braking of the external side wheels is offered. The equation describing the condition of four-wheel drive vehicle crab motion is obtained. The purpose of the research is to determine the law of control of torque on the wheels of the car, the realization of which makes crab motion possible. For realization of the aim, the following challenges were solved: the torque difference on the driving wheels (the braking torque on the outside wheel) that provides “crab motion" is determined;an analysis of the operational factors influences and design parameters of the vehicle, on the magnitude of the required torque difference, was conducted.The angle of rotation of the track wheels determines the direction of vehicle movement, and the torque difference on the driving wheels creates a moment stabilizing the position of the vehicle and ensures the straightness of the trajectory of motion.The linear velocity at which “crab motion" is possible without creating a torque difference on the driving wheels…

Energy-Management Strategy for Four-Wheel Drive Electrohydraulic Hybrid System with Optimal Comprehensive Efficiency

SAE International Journal of Passenger Cars - Electronic and Electrical Systems

Chongqing University, China-Yang Yang, Ke Lu, Chunyun Fu
  • Journal Article
  • 07-12-01-0004
Published 2019-08-22 by SAE International in United States
The four-wheel drive electric sport utility vehicle (SUV) requires high dynamic performance, and the front and rear axles are matched with a high-power motor. High-power motors operate under low-speed and low-torque conditions, with low efficiency and large power loss. To reduce the power loss under low-speed and low-load conditions, a hybrid system of front and rear dual motors and dual hydraulic pumps/motors is designed. A simulation model of a four-wheel drive SUV electrohydraulic hybrid system is constructed. Aiming at the optimal energy consumption, a dynamic programming algorithm is adopted to establish the driving control rules of the vehicle. Constrained by the Economic Commission for Europe Regulation No.13 (ECE R13), a braking-force distribution strategy for the front and rear axles is formulated. On the premise of satisfying the braking safety, regenerative braking is preferred, and the braking energy is recovered to the greatest extent possible. The optimal efficiency curve of the motor is identified, and an energy-management strategy based on the optimal efficiency curve of the motor is established. The comprehensive efficiency of the dual motor…

CATARC New Type Drivetrain NVH Test Facility

CATARC-Hui Gao, Yongchao Wang, Dong Wang
Jilin University-HongBin Yin
Published 2019-04-02 by SAE International in United States
A vehicle’s NVH performance has a significant impact on the user experience of the driver and passengers. About one-third of the vehicle complaints are related to NVH performance. As the core component of the vehicle, the drivetrain’s NVH characteristics have a significant impact on vehicle comfort. How to reliably and stably reproduce the specific condition of the whole vehicle through the test method, and obtain the highly consistent objective data for analyzing and improving the NVH characteristics of the drivetrain is of great significance in engineering. For this purpose, China Automotive Technology Research Center Co., Ltd. (CATARC) designed and built a new type drivetrain NVH test facility, which consists of five dynamometers, and can carry horizontal/vertical, front/rear drive or four-wheel drive structures including powertrain, transmission, and rear axle, or even a whole vehicle. Because of equipped with battery simulator, the above specimens of fuel vehicle, hybrid vehicle and electric vehicle can be mounted. The various functions of the facility enable a series of NVH tests such as gear whine, gear rattle, torsional vibration, and gear…
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An Exploratory Assessment of Electrified Propulsion Systems for Full-Size Heavy-Duty Truck Applications

General Motors Global Research and Development-Alok Warey, Norman Bucknor, Ian Sutherland, Michael Potter
Published 2019-01-18 by SAE International in United States
Powertrain electrification could be a key enabler for compliance with future exhaust emission standards and carbon dioxide (CO2) emissions limits or a customer facing product differentiator.The main objective of this study was to assess the potential of electrified propulsion systems in achieving a substantial reduction in CO2 emissions when applied to a representative full-size heavy-duty (HD) truck compared to the baseline configuration. A representative full-size HD four-wheel drive (4WD) truck of adjusted loaded vehicle weight (ALVW) 4082 kg or 9000 lbs with a 6.6 L diesel engine was simulated with various electrified drive configurations over the combined US FTP-72 (Federal Test Procedure) cycle and the Highway Fuel Economy Test (HWFET). Every hybrid vehicle configuration used in the study was designed using representative battery pack and electric drive components. Stop-start (S/S) functionality with a belt alternator starter (BAS) system provided a 2.5% benefit in CO2 emissions over the cycle compared to the baseline vehicle. Application of various electrified drive systems resulted in a total CO2 emissions benefit of 8.5% with a 48V P0 configuration to 25%…
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Graphical Symbols for Operator Controls and Displays on Off-Road Self-Propelled Work Machines

HFTC2, Machine Displays and Symbols
  • Ground Vehicle Standard
  • J1362_201812
  • Current
Published 2018-12-07 by SAE International in United States
SAE J1362 presents graphical symbols for use on operator controls and other displays on off-road work machines as defined in SAE J1116 plus mobile cranes but excluding agricultural tractors. Symbols for agricultural tractors are covered by ASABE S304, ISO 3767-1, and ISO 3767-2.
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Electric Motors for Driveline Actuation Standard Terminology, Test Parameters, and Equipment Requirements

Drivetrain Standards Committee
  • Ground Vehicle Standard
  • J3104_201811
  • Current
Published 2018-11-26 by SAE International in United States
This document will apply to the most common applications of electric motors, used for activating all-wheel drive (AWD) and four-wheel drive (4WD) disconnect systems as used in passenger (car and light truck) vehicles. The standard will provide consistent definition, terminology, tests, and reporting methods.
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Open Access

Comparative Performance of 12 Crankcase Oil Mist Separators

SAE International Journal of Engines

Curtin University, Australia-Vahid Golkarfard, Ramanathan Subramaniam, Jonathan Broughton, Andrew King, Benjamin Mullins
  • Journal Article
  • 03-12-01-0001
Published 2018-10-31 by SAE International in United States
Closed crankcase ventilation (CCV) systems are required in most automotive markets in order to meet emissions regulations. Such systems usually require a separator to recover oil and return it to the sump. Many end users fit improved separators in order to reduce intake/aftercooler contamination with soot/oil. This study measured clean and wet pressure drop and filter capture efficiency in 12 different crankcase oil mist separators which are commonly used for either original equipment (OE) or aftermarket fitment to passenger vehicles and four-wheel drives (≤200 kW). The filters tested spanned three different size/rating classes as well as included both branded and unbranded (imitation) models. In addition to filters, separators (often termed “catch cans”) and an OE cyclone separator were also examined. Testing was performed under controlled laboratory conditions using methods equivalent to previous work and current mist filter test standards. All separators were tested at flow rates between 50 and 250 lpm in both dry and “wet” (saturated with oil) states. Filtration/separation efficiency was also measured. Separators were compared based on quality factor (ratio of capture…

Airline Tow Tractor - Baggage/Cargo Factors for Design Consideration

AGE-3 Aircraft Ground Support Equipment Committee
  • Aerospace Standard
  • AIR1316B
  • Current
Published 2018-09-27 by SAE International in United States
This document outlines the functional and design requirements for baggage/cargo tow tractors used for airline services.
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Battery Powered Aircraft Tow Tractors - Factors for Design Consideration

AGE-3 Aircraft Ground Support Equipment Committee
  • Aerospace Standard
  • AIR1854A
  • Current
Published 2018-09-27 by SAE International in United States
This SAE Aerospace Information Report (AIR) identifies and summarizes the various factors that must be considered and evaluated by the design or specifying engineer in establishing the specifications and design characteristics of battery-powered aircraft tow tractors. This AIR is presented in two parts. The first part is simply a summarization of design factors that must be considered in establishing vehicle specifications and design characteristics. The second part refers particularly to the performance characteristics of an aircraft tow tractor. Some definitions, formulas, data, and an example are provided mainly for assisting the specifying engineers of potential buyers and users of aircraft tow tractors in the evaluation and comparison of their requirements with the performance capabilities of the various tow tractors offered by the tow tractor manufacturers. Although the design engineers could also use the formulas and data in their calculations of the performance specifications of aircraft tow tractors, this AIR is not intended to provide the methods and all data necessary for detailed calculations and design of a battery-powered aircraft tow tractor.
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Velocity Trajectory Planning for Energy Savings of an Intelligent 4WD Electric Vehicle Using Model Predictive Control

Dongfeng Commercial Vehicle-Yang Li, Xiaobo Yang, Xinyue Lu
Wuhan Univ of Technology-Yue Li, Dongmei Wu, Changqing Du, Huiping Yang
Published 2018-08-07 by SAE International in United States
To reduce the fuel consumption of an intelligent four-wheel-drive (4WD) electric vehicle (EV), this paper presents a new method of speed trajectory planning. The proposed method can realize a fast real-time optimization of vehicle speed, aiming to achieve the minimum motor energy output according to the fuel consumption directly. In addition, the optimization method maintains the cruising speed within the deviation required to achieve a good control effect. First, the road slope information is considered, and then, a 4WD EV longitudinal dynamic prediction model and a fuel consumption function are established. Next, the state and control variables are chosen to establish the cost function; in this manner, the MPC optimization problem in each prediction horizon is transformed into quadratic form. Finally, the fast solving tool called GRAMPC is used to solve the MPC problem. The calculation results show that the average fuel consumption is reduced compared with that of normal driving, and the calculation time is significantly shortened, even with a large number of sample times.
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