Your Selections

Maintenance and Aftermarket
Aircraft operations
Aircraft deicing
Ground support
Cleaning
Customization
Diagnostics
Fleet management
Ground vehicle operations
Maintainability and supportability
Maintenance, repair, and overhaul (MRO)
Performance upgrades
Prognostics
Technician training
Tools and equipment
Vehicle health management (VHM)
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

Series

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

Time Domain Full Vehicle Interior Noise Calculation from Component Level Data by Machine Learning

Mercedes-Benz AG-Dimitrios Ernst Tsokaktsidis, Clemens Nau
Technical University of Munich-Steffen Marburg
  • Technical Paper
  • 2020-01-1564
To be published on 2020-06-03 by SAE International in United States
Computational models directly derived from data gained increased interest in recent years. Data-driven approaches have brought breakthroughs in different research areas such as image-, video- and audio-processing. Often denoted as Machine Learning (ML), today these approaches are not widely applied in the field of vehicle Noise, Vibration and Harshness (NVH). Works combining ML and NVH mainly discuss the topic with respect to psychoacoustics, traffic noise, structural health monitoring and as improvement to existing numerical simulation methods. Vehicle interior noise is a major quality criterion for today’s automotive customers. To estimate noise levels early in the development process, deterministic system descriptions are created by utilizing time-consuming measurement techniques. This paper examines whether pattern-recognizing algorithms are suitable to conduct the prediction process for a steering system. Starting from operational measurements, a procedure to calculate the sound pressure level in the passenger cabin is developed and investigated. Component time domain data serves as basis for the computation. The important inputs are determined by a correlation analysis. Input selection is followed by data reduction. After preprocessing, a supervised learning…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Direction Specific Analysis of Psychoacoustics Parameters Inside Car Cockpits: a Novel Tool for NVH and Sound Quality

University of Parma-Daniel Pinardi, Costante Belicchi, Angelo Farina, Marco Binelli
University of Parma / ASK Industries SpA-Lorenzo Ebri
  • Technical Paper
  • 2020-01-1547
To be published on 2020-06-03 by SAE International in United States
Psychoacoustics parameters are widely employed in automotive field for objective evaluation of Sound Quality of vehicle cabins and their components. The standard approach relies on binaural recordings from which numerical values and curves are calculated and head-locked binaural listening playback can be performed. Recently, the Virtual Reality technology started to diffuse also in automotive field, bringing new possibilities for enhanced and immersive listening sessions. In this paper, we combine both solutions: the VR approach is adopted to calculate the principal psychoacoustics parameters. The acquisition system consists in a massive spherical microphone array featuring a camera for recording panoramic visual background. The acoustical information is encoded into High Order Ambisonics spatial format, that can be rendered on stereoscopic visors and Spatial PCM Sampling format that can be used to produce 360° colour maps. In this way, we are able to plot the psychoacoustics parameters adding their directivity information over the panoramic background, turning the array into a novel 360° diagnostic tool. At the same time, the playback can be performed inside Ambisonics listening rooms or binaurally…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Unsettled Topics on the Use of IVHM in the Active Control Loop

Collins Aerospace-Rhonda Walthall
  • Research Report
  • EPR2020011
To be published on 2020-05-26 by SAE International in United States
The growth in global economies has led to a world that has become much more mobile in the last few decades. The number of enplanements has increased and is expected to continue to do so at an annual average rate of 1.8% through 2039 . Concurrently, the number of aircraft in service has expanded substantially and will continue to expand while aircraft become ever more complex. The design of future generation of aircraft will benefit from the technologies that are being accelerated for these new mobility platforms. Technologies, such as artificial intelligence and fault tolerant and self-adapting control, will use integrated vehicle health management (IVHM) capabilities as part of the decision-making processes. This SAE EDGE™ report seeks to explore the unsettled issues surrounding embedding IVHM information into the active control loops of modern aircraft systems and in future generations of aircraft designs. NOTE: SAE EDGE™ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE™ Research Reports is…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

UDM Tip Temperature Control using Thermosyphon Principle

Mahindra & Mahindra, Ltd.-Samson Solomon, Rajesh Thiyagarajan, Parvej Khan
  • Technical Paper
  • 2020-28-0040
To be published on 2020-04-30 by SAE International in United States
In today’s automobile industry where BS6 is posing a high challenge and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and meeting challenging engineering requirement. Thus, the frugal engineering comes into the picture. An important technology that has come into highlight in recent years is the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other. The Flow through the UDM is maintained by changing Temperature (hence density) of the fluid at one end using the force airflow. The main objective of the UDM cooling is to keep the UDM tip temperature below 120…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Improvement of Tightening Reliability of Bolted Joints Using Elliptical Confidence Limit in Calibrated Wrench Method

Tokyo Metropolitan University-Soichi Hareyama, Ken-ichi Manabe, Satoshi Kobayashi
  • Technical Paper
  • 2020-01-0218
To be published on 2020-04-14 by SAE International in United States
The calibrated wrench method is used in the tightening of bolts in manufacturing industries in the case of a large amount of tightening work. It is important to apply a large initial clamping force to ensure tightening reliability and prevent self-loosening, fatigue breakage, and so forth. In this method, the clamping force of bolted joints is controlled using a torque wrench. However, since the clamping force is indirectly applied by a wrench, it varies greatly in the case of a large amount of tightening in a factory. Therefore, the calibrated wrench method is not so accurate from the viewpoint of clamping force control. It is conventionally thought that the distribution of the clamping force has the shape of a rhombus. When tightening torque and clamping force are considered to be two independent random variables, the clamping force is distributed within an elliptical confidence limit. Here, we show that the distribution of equivalent stress also has an elliptical confidence limit. Considering the permitted limit for working load stress on a bolted joint, the elliptical distribution has…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Application of Multivariate Control Chart Techniques to Identifying Nonconforming Pallets in Automotive Assembly Plants

FCA US LLC-Michael Huang, Yuqin Wang
University of Texas at San Antonio-Adel Alaeddini
  • Technical Paper
  • 2020-01-0477
To be published on 2020-04-14 by SAE International in United States
The Hotelling multivariate control chart and the sample generalized variance |S| are used to monitor the mean and dispersion of underbody data including the pallet information to identify the non-conforming pallets. An iterative procedure and the Gaussian mixture model (GMM) are used to rank the non-conforming pallets in the order of severity. The multivariate Hotelling T^2 test statistic with Mason-Tracy-Young (MYT) signal decomposition method are used to identify the features that are affected by the non-conforming pallets. These algorithms were implemented in Advanced Pallet Analysis module of FCA Body Shop Analysis Tool (BSAT). The identified non-conforming pallets are displayed in a scatter plot with different color for each pallet. The run chart of an affected feature confirms the nonconforming pallets by highlighting data points from the nonconforming pallet. The analysis module has been successfully used in the body shops of FCA plants. One example is presented to demonstrate the application.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Investigation of the Effectiveness of a Passive Device for Soiling Mitigation for Vehicle Side-Cameras

Ontario Tech University-William Collings, Wing Yi Pao, Martin Agelin-chaab
  • Technical Paper
  • 2020-01-0699
To be published on 2020-04-14 by SAE International in United States
The development of modern autonomous automotive technology depends heavily on the reliable performance of external sensors that are vulnerable to soiling. Existing active cleaning devices, such as washers and wipers, are relatively complex and expensive. Furthermore, little research has been done on alternative soiling mitigation strategies and devices for sensors. With the emerging trend of replacing side-mirrors with camera monitor systems, it is important for such systems to stay clean in adverse weather in order to provide critical navigation information. To meet this need, a passive aerodynamics-based cleaning device was investigated. A converging vent device was integrated into the side-camera housing and the subsequent degree of soiling was estimated at a wind speed of 20 m/s (72 km/h), representing urban and suburban driving speeds. The vent outlet height and outlet jet angle of the vent device were varied and the variants were compared to the non-vented reference model. The degree of soiling was evaluated experimentally and computationally. The variants were 3D-printed and sprayed with water in wind tunnel tests, where the degree of soiling was…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

A Comparison of Componentization Constructs for Supporting Modularity in Simulink

FCA Canada Inc., McMaster University-Monika Jaskolka
McMaster University-Vera Pantelic, Alan Wassyng, Mark Lawford
  • Technical Paper
  • 2020-01-1290
To be published on 2020-04-14 by SAE International in United States
The Model-Based Development (MBD) paradigm is widely used for embedded controls development, with the MathWorks Simulink modelling environment being extensively used in the automotive industry. As production-scale Simulink models are typically large and complex, there exists a need to decompose them properly in order to facilitate their maintainability, understandability, and evolution. MathWorks recommends the use of three constructs for model “componentization” or decomposition: the Subsystem, Library, and Model Reference. However, a recently added construct introduced in Simulink R2014b, the Simulink Function, can also be used for this purpose, while also supporting information hiding due to the construct’s ability to be scoped and encapsulate data. This paper provides an in-depth comparison of these Simulink constructs to fully understand the differences in their reusability, sharing of program state, encapsulation, and code generation, with the goal of facilitating model evolution. An automotive powertrain example is provided to highlight the differences between approaches. Conventions for structuring models are also presented.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Improved Customer Experience through Electric Vehicle Sound Enhancement

General Motors LLC-Frank Valeri, Glenn Pietila
  • Technical Paper
  • 2020-01-1361
To be published on 2020-04-14 by SAE International in United States
Electric Vehicles are typically thought of as being quiet and refined, but they do come with some unique N&V challenges. Some of these challenges include a natural sound that can be undesirable due to its tonal nature, presence of high frequency, discontinuities in sound, and characteristics and levels that do not always naturally increase with motor torque and vehicle speed. One approach to address those challenges is Electric Vehicle Sound Enhancement (EVSE) which is a software feature embedded within the infotainment system. EVSE can be used to improve the perception of the vehicle by enhancing the preferred natural sounds of the vehicle, masking unusual and annoying components of the sound and aurally conveying information related to the vehicle performance. A jury study was conducted to better understand how EVSE can be used to accomplish this. This paper will summarize a typical EVSE system and highlight some of the tools and methods that can be used to develop an EVSE tuning that mitigates unpleasant sounds while enhancing the customer experience without completely changing the vehicle DNA.…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Chip and Board Level Digital Forensics of Cummins Heavy Vehicle Event Data Recorders

Colorado State University-Jeremy Daily, Duy Van
Delta v Forensic Engrg-Matthew DiSogra
  • Technical Paper
  • 2020-01-1326
To be published on 2020-04-14 by SAE International in United States
Crashes involving Cummins powered heavy vehicles can damage the electronic control module (ECM) containing heavy vehicle event data recorder (HVEDR) records. When ECMs are broken and data cannot be extracted using vehicle diagnostics tools, more invasive and low-level techniques are needed to forensically preserve and decode HVEDR data. A technique for extracting non-volatile memory contents using non-destructive board level techniques through the available in-circuit debugging port is presented. Additional chip level data extraction techniques can also provide access to the HVEDR data. Once the data is obtained and preserved in a forensically sound manner, the binary record is decoded to reveal typical HVDER data like engine speed, vehicle speed, accelerator pedal position, and other status data. The memory contents from the ECM can be written to a surrogate and decoded with traditional maintenance and diagnostic software. The research also shows the diagnostic trouble codes from the ECM are preserved. In other words, the digital forensic technique of extracting memory contents through the in-circuit debugging port does not introduce any new fault codes. Cryptographic hashing of…