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Driveline NVH Integration of An NA Truck Program

American Axle & Manufacturing-Ying Peng, Zhenghong Shi, Christopher Folts, Gregory Kopp, Zhaohui Sun, Alexander Sandstrom
Published 2019-06-05 by SAE International in United States
In the current automotive industry, it is common that the driveline subsystem and components are normally from different automotive suppliers for OEMs. In order to ensure proper system integration and successful development of driveline system NVH performances, collaboration efforts between OEMs and suppliers are very demanding and important.In this paper, a process is presented to achieve successfulness in developing and optimizing vehicle integration through effective teamwork between a driveline supplier and a major OEM. The development process includes multiple critical steps. They include target development and roll down, targets being specific and measurable, comprehension of interactions of driveline and vehicle dynamics, accurate definition of sensitivity, proper deployment of modal mapping strategy, which requires open data sharing; and system dynamics and optimization. More specially, the supplier can work with OEM to seek the most cost-effective solutions, through tuning the driveline system dynamics to provide "quiet" frequency zone against vehicle sensitivity, to avoid normally needed costly suspension changes. Two case studies of a pick-up vehicle driveline program integration are used in this paper to illustrate the effectiveness…
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Reducing NVH through refined powertrain measurement

Automotive Engineering: June 2019

Author Scott Zagorski, Ph.D, PE, is a mechanical engineer who has been performing vehicle testing/vehicle dynamics for 15 years. He has been with S-E-A for four years.-Scott Zagorski
  • Magazine Article
  • 19AUTP06_04
Published 2019-06-01 by SAE International in United States

The C1000 vastly simplifies measuring the mass matrix of heavy, odd shaped engines and powertrains.

Accurate measurements of vehicle centers-of-gravity and inertia are vital for helping NVH engineers further improve their dynamic vehicle models-and thus improve performance and safety. Specialized vehicle test machines are used for NHTSA's New Car Assessment Program (NCAP) and new variations are entering service for the subsystem level. One of them is the C1000, developed by S-E-A Vehicle Dynamics headquartered in Columbus, Ohio.

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Fundamentals of Vehicle Dynamics

  • Professional Development
  • PD731620
Published 2019-05-31

Vehicle design always involves conflicting goals. A suspension system that’s optimized for ride is not always the best for handling. The powertrain that gives best acceleration is not likely to be the most fuel-efficient.


Ride Index Structure and Development Methodology

Vehicle Dynamics Standards Committee
  • Ground Vehicle Standard
  • J2834_201904
  • Current
Published 2019-04-24 by SAE International in United States
This recommended practice defines methods for the measurement of periodic, random and transient whole-body vibration. It indicates the principal factors that combine to determine the degree to which a vibration exposure will cause discomfort. Informative appendices indicate the current state of knowledge and provide guidance on the possible effects of motion and vibration on discomfort. The frequency range considered is 0.5 Hz to 80 Hz. This recommended practice also defines the principles of preferred methods of mounting transducers for determining human exposure. This recommended practice is applicable to light passenger vehicles (e.g., passenger cars and light trucks). This recommended practice is applicable to motions transmitted to the human body as a whole through the buttocks, back and feet of a seated occupant, as well as through the hands of a driver. This recommended practice offers a method for developing a ride performance index but does not specifically describe how to apply this index to assessment or comparison of specific vehicles.
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Lateral and Tangential Accelerations of Left Turning Vehicles from Naturalistic Observations

Kineticorp LLC-Neal Carter, Steven Beier, Rheana Cordero
Published 2019-04-02 by SAE International in United States
When reconstructing collisions involving left turning vehicles at intersections, accident reconstructionists are often required to determine the relative timing and spacing between two vehicles involved in such a collision. This time-space analysis frequently involves determining or prescribing a path and acceleration profile for the left turning vehicle. Although numerous studies have examined the straight-line acceleration of vehicles, only two studies have presented the tangential and lateral acceleration of left turning vehicles. This paper expands on the results of those limited studies and presents a methodology to automatically detect and track vehicles in a video file. The authors made observations of left turning vehicles at three intersections. Each intersection incorporated permissive green turn phases for left turning vehicles. The authors recorded video of left turning vehicles at each intersection from a small unmanned aerial system (sUAS), and that video was analyzed with a convolutional neural network designed to detect vehicles. The detected vehicles were then tracked over time and the results were analyzed. A total of 86 left turning vehicles were analyzed. In 23 of the…
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Analysis of Passive Low Power Phase Change Heat Dissipation Method for Electric Vehicle Motor

Suizhou-WUT Industry Research Institute-Gangfeng Tan
Wuhan University of Technology-Shiping Huang, Yishi Wang, Jianjie Kuang, Jiakang Quan, Xiaofei Ma
Published 2019-04-02 by SAE International in United States
The electric vehicle motor is developing toward high power density, at the same time brings serious temperature rise problem, which affect the driving motor performance, efficiency, and useful life. Liquid cooling is usually used to solve the problem, but its energy consumption is large and the reliability is poor. In order to solve this problem, this paper proposes a heat dissipation method to improve the reliability and energy efficiency of the driving motor heat dissipation system. The method uses heat pipes heat transfer, and the heat pipes cold end are cooled by vehicle facing the wind. By establishing the motor temperature rise model, heat transfer model and vehicle dynamics model, this paper analyzes the maximum temperature region and reliability of the driving motor heat dissipation system, calculates and analyzes the efficiency of the driving motor under different driving conditions. The results show that with the heat dissipation method of this paper, the reliability of the driving motor cooling system has been improved; the overall efficiency of the driving motor can be increased by 7.4%-27.9% and…
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How to Model Real-World Driving Behavior? Probability-Based Driver Model for Energy Analyses

Daimler AG-Tobias Schuermann, Tobias Goedecke, Stefan Schmiedler, Daniel Goerke
University of Applied Sciences Esslingen-Kai André Boehm
Published 2019-04-02 by SAE International in United States
A wide variety of applications such as driver assistant and energy management systems are researched and developed in virtual test environments. The safe testing of the applications in early stages is based on parameterizable and reproducible simulations of different driving scenarios. One possibility is modeling the microscopic driving behavior to simulate the longitudinal vehicle dynamics of individual vehicles. The currently used driver models are characterized by a conflict regarding comprehensibility, accuracy and calibration effort. Due to the importance for further analyses this conflict of interests is addressed by the presentation of a new microscopic driver model in this paper. The proposed driver model stores measured driving behaviors with its statistical distributions in maps. Thereby, the driving task is divided into free flow, braking in front of stops and following vehicles ahead. This makes it possible to display the driving behavior in its entirety. The comprehensibility of this driver model is given by its simplicity and the calibration effort is low with existing measurement data. These data are recorded with a testing vehicle by a map-…
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Development of a Standalone Application in MATLAB to Generate Brake Performance Data

Indian Institute of Technology-Harsh Kumar Singh
Mahindra & Mahindra, Ltd.-Babasaheb Shinde
Published 2019-04-02 by SAE International in United States
Predicting the brake performance and characteristics is a crucial task in the vehicle development activity. Performance prediction is a challenge because of the involvement of various parts in the brake assembly like booster, master cylinder, calipers, disc and drum brakes. Determination of these characteristics through vehicle level tests requires a lot of time and money. This performance prediction is achieved by theoretical calculations involving vehicle dynamics. The final output must satisfy the regulations. This project involves the creation of a standalone application using MATLAB to predict the various brake performances such as: booster characteristics, adhesion curves, deceleration and pedal effort curves, behavior of brakes during brake and booster failed conditions and braking force diagrams based on the given user inputs. Previously, MS Excel and an application developed in the TK Solver environment was used to predict the brake performance curves. Debugging and inclusion of new modules was a major issue in old applications. Also, the previous applications lacked ABS module, which after the new government norms will be implemented in every vehicle. Thus, there was…
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Snowmobile Lane Change Dynamics with One and Two Occupants

30 Forensic Engineering-Mark Paquette, Harrison Griffiths
Published 2019-04-02 by SAE International in United States
As with other motor vehicles, snowmobile operators are occasionally presented with potential hazards that require a response to avoid an impending collision. The typical responses involve either braking, steering, or a combination of both. Although the braking deceleration capabilities of snowmobiles have been documented in several published studies, there is a lack of available data regarding the swerving capability of snowmobiles. In addition, it is unknown if the presence of a passenger on a snowmobile negatively affects its swerving capabilities, and if so, to what extent. This paper presents data gathered during swerve testing conducted on an instrumented snowmobile in northern Ontario with two different operators, and with one and two occupants.
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Sensitivity Analysis of Tire-Soil Interaction Using Finite Element Analysis and Smoothed Particle Hydrodynamics Techniques

UOIT-Mirwais Sharifi, Moustafa El-Gindy
University of Ontario Institute of Technology-Zeinab El-Sayegh
Published 2019-04-02 by SAE International in United States
This paper presents the modelling, calibration and sensitivity analysis of LETE sand soil using Visual Environment’s Pam Crash. LETE sand is modelled and converted from Finite Element Analysis mesh (FEA) to Smooth-particle hydrodynamics (SPH). The sand is then calibrated using terramechanics published data by simulating a pressure sinkage test and shear box test using the SPH LETE sand particles. The material properties such as tangent modulus, yield strength and bulk modulus are configured so the simulation’s results match those of theoretical values. Sensitivity analysis of the calibrated LETE sand material is then investigated. The sensitivity analysis includes mesh size, plate geometry, smoothing length, max smoothing length, artificial viscosity and contact thickness. The effect of these parameters on the sand behavior is analyzed. Finally, SPH LETE Sand is used to determine the rolling resistance coefficient of FEA off-road truck tire size 315/80R22.5 for different mesh size sand particles. The results found within this paper will be continued in regard to achieving better understanding of vehicle dynamics for tire-terrain interaction.
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