Your Selections

General Motors Company
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Making a Regional Belt Drive Rack Electric Power Steering System Global

General Motors Company-Marcos F. Colombini
Mando Corporation-Thomas Cook
Published 2017-11-07 by SAE International in United States
An actual trend in the automotive industry is to have global products in order to have economy of scale.This paper presents how a Belt Drive Rack EPS developed for the North American market had to be modified in order to be assembled in a Vehicle sold all around the world.Main technical challenges for achieving that goal were generated from different Architectures, whether electrical or mechanical, used in each vehicle, Packaging issues and Regional Requirements. Main features affected are Database Configuration, Electromagnetic Compatibility, Smooth Road Shake mitigation and Pull Compensation.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Trivial Principal Component Analysis (TPCA): An Improved Modeling Approach

General Motors Company-Balakrishna Chinta
Published 2017-03-28 by SAE International in United States
Trivial Principal Component method (TPC) was developed recently to model a system based on measured data. It is a statistical method that utilizes Eigen-pairs of covariance matrix obtained from the measured data. It determines linear coefficients of a model by using the trivial eigenvector corresponding to the least eigenvalue. In general, linear modeling accuracy depends on the strength of nonlinearity and interaction terms as well as measurement error. In this paper, the TPC method is extended to analyze residual (error) vector to identify significant higher order and interaction terms that contribute to the modeling error. Subsequently, these additional terms are included for constructing a robust system model. Also, an iterative TPC analysis is proposed for the first time to correct the model gradually till the least eigenvalue becomes minimum. For illustration, example problems are presented to bring out the potential and novelty of the TPC method for improved modeling and the results are compared with linear regression model.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental Investigation of Fuel Film Characteristics of Ethanol Impinging Spray at Ultra-Low Temperature

General Motors Company-Tang-Wei Kuo, Ronald O. Grover, Scott E. Parrish
Shanghai Jiao Tong University-Hujie Pan, Min Xu, Xue Dong
Published 2017-03-28 by SAE International in United States
Increasing the injection pressure in DISI engine is an efficient way to obtain finer droplets but it will also potentially cause spray impingement on the cylinder wall and piston. Consequently, the fuel film sticking on the wall can dramatically increase the soot emission of the engine especially in a cold start condition. On the other hand, ethanol is widely used as an alternative fuel in DI engine due to its sustainable nature and high octane number. In this study, the fuel film characteristics of single-plume ethanol impinging spray was investigated. The experiments were performed under ultra-low fuel/plate temperature to simulate the cold start condition in cold areas. A low temperature thermostatic bath combined with specially designed heat exchangers were used to achieve ultra-low temperature for both the impinging plate and the fuel. Laser induced fluorescence (LIF) technique was employed to measure the thickness of fuel film deposited on the impinging plate. Rhodamine 6G was resolved into ethanol as the tracer, which can be excited by 532 nm laser and fluorescence at 560-590 nm. A low…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Study of Hybrid III 5th Percentile Female ATD Chest Accelerometers to Assess Sternum Compression Rate in Chest on Module Driver Out-of-Position Evaluations

General Motors Company-Ke Dong, Brian Putala, Kristen Ansel
Published 2017-03-28 by SAE International in United States
Driver out-of-position (OOP) tests were developed to evaluate the risk of inflation induced injury when the occupant is close to the airbag module during deployment. The Hybrid III 5th percentile female Anthropomorphic Test Device (ATD) measures both sternum displacement and chest acceleration through a potentiometer and accelerometers, which can be used to calculate sternum compression rate. This paper documents a study evaluating the chest accelerometers to assess punch-out loading of the chest during this test configuration. The study included ATD mechanical loading and instrumentation review. Finite element analysis was conducted using a Hybrid III - 5th percentile female ATD correlated to testing. The correlated restraint model was utilized with a Hybrid III - 50th percentile male ATD. A 50th percentile male Global Human Body Model (HBM) was then applied for enhanced anatomical review. The results illustrate differences in chest response between the Hybrid III dummy and the human body model in chest on module driver OOP evaluations.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation of Prog-Die Wear Properties on Bare DP1180 Steel

SAE International Journal of Engines

General Motors Company-Donald Adamski
AK Steel Corporation-Wei Wu, Yu-Wei Wang
  • Journal Article
  • 2017-01-0310
Published 2017-03-28 by SAE International in United States
The die wear up to 80,800 hits on a prog-die setup for bare DP1180 steel was investigated in real production condition. In total, 31 die inserts with the combination of 11 die materials and 9 coatings were evaluated. The analytical results of die service life for each insert were provided by examining the evolution of surface wear on inserts and formed parts. The moments of appearance of die defects, propagation of die defects, and catastrophic failure were determined. Moreover, the surface roughness of the formed parts for each die insert was characterized using Wyko NT110 machine. The objectives of the current study are to evaluate the die durability of various tooling materials and coatings for flange operations on bare DP 1180 steel and update OEM tooling standards based on the experimental results. The current study provides the guidance for the die material and coating selections in large volume production for next generation AHSSs.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Engine Diagnostics Using Acoustic Emissions Sensors

SAE International Journal of Engines

General Motors Company-Akram Zahdeh
Oak Ridge National Laboratory-Brian C. Kaul
  • Journal Article
  • 2016-01-0639
Published 2016-04-05 by SAE International in United States
Engine acoustics measured by microphones near the engine have been used in controlled laboratory settings for combustion feedback and even combustion phasing control, but the use of these techniques in a vehicle where many other noise sources exist is problematic. In this study, surface-mounted acoustic emissions sensors are embedded in the block of a 2.0L turbocharged GDI engine, and the signal is analyzed to identify useful feedback features. The use of acoustic emissions sensors, which have a very high frequency response and are commonly used for detecting material failures for health monitoring, including detecting gear pitting and ring scuffing on test stands, enables detection of acoustics both within the range of human hearing and in the ultrasonic spectrum. The high-speed acoustic time-domain data are synchronized with the crank-angle-domain combustion data to investigate the acoustic emissions response caused by various engine events.Combustion can clearly be identified as a high energy event in the acoustic emissions data with the frequency of the response corresponding to a resonant mode of the combustion chamber. Additionally, both the start and…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Health Ready Components-Unlocking the Potential of IVHM

SAE International Journal of Materials and Manufacturing

General Motors Company-Steven Holland
Boeing Research & Technology-Robab Safa-Bakhsh
  • Journal Article
  • 2016-01-0075
Published 2016-04-05 by SAE International in United States
Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.A great benefit can be achieved if a common approach is developed to assist suppliers in the development of “health-ready” components and systems and to simplify the process by which integrators use these capabilities to deploy IVHM applications. In this context, the term “health ready” refers to…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Experimental and Numerical Investigations of Close-Coupled Pilot Injections to Reduce Combustion Noise in a Small-Bore Diesel Engine

SAE International Journal of Engines

General Motors Company-Alok Warey, Francesco Pesce, Richard Peterson, Alberto Vassallo
Sandia National Laboratories-Stephen Busch, Kan Zha, Paul C. Miles
  • Journal Article
  • 2015-01-0796
Published 2015-04-14 by SAE International in United States
A pilot-main injection strategy is investigated for a part-load operating point in a single cylinder optical Diesel engine. As the energizing dwell between the pilot and main injections decreases below 200 μs, combustion noise reaches a minimum and a reduction of 3 dB is possible. This decrease in combustion noise is achieved without increased pollutant emissions. Injection schedules employed in the engine are analyzed with an injection analyzer to provide injection rates for each dwell tested. Two distinct injection events are observed even at the shortest dwell tested; rate shaping of the main injection occurs as the dwell is adjusted. High-speed elastic scattering imaging of liquid fuel is performed in the engine to examine initial liquid penetration rates. The penetration rate data provide evidence that rate shaping of the initial phase of the main injection is occurring in the engine and that this rate shaping is largely consistent with the injection rate data, but the results demonstrate that these changes are not responsible for the observed trend in combustion noise.A zero-dimensional model is created to…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Dry Dual Clutch Transmission (DCT) Thermal Model

General Motors Company-Kumaraswamy Hebbale, Farzad Samie, Jonathan Kish
Published 2015-04-14 by SAE International in United States
Dual Clutch Transmissions (DCT) for passenger cars are being developed by OEMs and suppliers. The driving force is the improvement in fuel economy available from manual transmissions together with the comfort of automatic transmissions. A dry clutch system (dDCT) is currently the subject of research, development, and production implementation. One of the key issues in the development of a dDCT is clutch durability. In dry clutches with current linings, above a critical temperature, the friction system starts to suffer permanent damage. In addition, the clutch friction characteristics are a function of the clutch interface temperature. Because a reliable, low-cost temperature sensor is not available for this application, the clutch control engineers rely on a good thermal model to estimate the temperature of the clutches.A thermal model was developed for dry dual clutch transmissions to predict operating temperature of both pressure and center plates during all maneuvers. The model is intended to be used to a) prevent clutch plate over-heating during abusive driving scenarios such as hill holding or multiple GCVW launches in both forward and…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

An Integrated Approach to Requirements Development and Hazard Analysis

General Motors Company-Mark Vernacchia, Padma Sundaram
Massachusetts Institute of Technology-John Thomas, John Sgueglia, Dajiang Suo, Nancy Leveson
Published 2015-04-14 by SAE International in United States
The introduction of new safety critical features using software-intensive systems presents a growing challenge to hazard analysis and requirements development. These systems are rich in feature content and can interact with other vehicle systems in complex ways, making the early development of proper requirements critical. Catching potential problems as early as possible is essential because the cost increases exponentially the longer problems remain undetected. However, in practice these problems are often subtle and can remain undetected until integration, testing, production, or even later, when the cost of fixing them is the highest.In this paper, a new technique is demonstrated to perform a hazard analysis in parallel with system and requirements development. The proposed model-based technique begins during early development when design uncertainty is highest and is refined iteratively as development progresses to drive the requirements and necessary design features. The technique is evaluated by applying it to a realistic but generic Shift-By-Wire design concept in two iterations with varying levels of detail. In addition, as the requirements and design evolve and change over time, the…
Annotation ability available