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Virtual Verification of Wrecker Tow Requirements

Ford Motor Company-Majid Tabesh, Steven Foster, Sethuprasant Boomipaulraj, Arthur Gariepy, Jim Alanoly
  • Technical Paper
  • 2020-01-0766
To be published on 2020-04-14 by SAE International in United States
Under various real-world scenarios, vehicles can become disabled and require towing. OEMs allow a few options for vehicle wrecker towing that include wheel lift tow using a stinger or towing on a flatbed. These methods entail multiple loading events that need to be assessed for damage to the towed vehicle. OEMs have several testing and evaluation methods in place for those scenarios with majority requiring physical vehicle prototypes. Recent focus to reduce product development time and cost has replaced the need for prototype testing with analytical verification methods. In this paper, the CAE method involving multibody dynamic simulation (MBDS) as well as finite element analysis (FEA) of vehicle flatbed operation, winching onto a flatbed, and stinger-pull towing are discussed. The simulations evaluate and address events such as bumper and underbody parts clearance to the ground, subframe impact with the stinger arm, chain loading on the body, as well as winch cable contact with underbody parts. MBD-FEA co-simulations is an option, but it may not work well when the design process involves disjoint teams, including suppliers.…
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Active grille shutters control and benefits in medium to large SUV: A system engineering approach

Jaguar Land Rover-Nilabza Dutta, Mark Spenley, Paul Cromback-Dugeny, Benjamin Stegmann, Wilko Jansen, Megan Parfitt
  • Technical Paper
  • 2020-01-0945
To be published on 2020-04-14 by SAE International in United States
Whilst the primary function of the active grille shutters is to reduce the aerodynamic drag of the car, there are some secondary benefits like improving the warm up time of engine and also retaining engine heat when parked. In turbocharged IC engines the air is compressed (heated) in the turbo and then cooled by a low temperature cooling system before going into the engine. When the air intake temperature exceeds a threshold value, the engine efficiency falls - this drives the need for the cooling airflow across the radiator in normal operation. Airflow is also required to manage the convective heat transfer across various components in engine bay for its lifetime thermal durability. Grill shutters can also influence the aerodynamic lift balance thus impacting the vehicle dynamics in high speed. The vehicle HeVAC system also relies on the condenser in the front heat exchanger pack disposing the waste heat off in the most efficient way. These requirements of maintaining optimal engine intake charge air temperature, managing condenser heat load, engine bay heat and aerodynamic lift…
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Challenges in Integrating Cybersecurity into Existing Development Processes

Invensity GmbH-Patric Lenhart, Paul Arndt, Jana von Wedel, Christian Beul, Jan Weldert
  • Technical Paper
  • 2020-01-0144
To be published on 2020-04-14 by SAE International in United States
For an established development process and a team accustomed to this process, adding cybersecurity features to the product initially means inconvenience and reduced productivity without perceivable benefits. Adapting development processes to take cybersecurity into account introduces challenges not present in engineering divisions so far. Strategies designed to deal with these challenges differ in the way in which added duties are assigned and cybersecurity topics are integrated into the already existing process steps. Cybersecurity requirements often clash with existing system requirements or established development methods, leading to low acceptance among developers, and introducing the need to have clear policies on how friction between cybersecurity and other fields is handled. A cybersecurity development approach is frequently perceived as introducing impediments, that bear the risk of cybersecurity measures receiving a lower priority to reduce inconvenience. Moreover, this leads to frustration among cybersecurity developers when their proposals are not accepted, and they feel their work is not appreciated. On the other hand, putting too much emphasis on cybersecurity leads to feature creep and makes the development unnecessarily complicated without…
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Modes of Automated Driving System Scenario Testing: Experience Report and Recommendations

AAA NCNU-Paul Wells, Atul Acharya
Silicon Valley Mobility-Sven Beiker
  • Technical Paper
  • 2020-01-1204
To be published on 2020-04-14 by SAE International in United States
With the widespread development of automated driving systems (ADS), it is imperative that standardized testing methodologies be developed to assure safety and functionality. Scenario testing evaluates the behavior of an ADS-equipped subject vehicle (SV) in predefined driving scenarios. This paper compares four modes of performing such tests: closed-course testing with real actors, closed-course testing with surrogate actors, simulation testing, and closed-course testing with mixed reality. In a collaboration between the Waterloo Intelligent Systems Engineering (WISE) Lab and AAA, six automated driving scenario tests were executed on a closed course, in simulation, and in mixed reality. These tests involved the University of Waterloo’s automated vehicle, dubbed the “UW Moose”, as the SV, as well as pedestrians, other vehicles, and road debris. Drawing on both data and the experience gained from executing these test scenarios, the paper reports on the advantages and disadvantages of the four scenario testing modes, and compares them using eight criteria. It also identifies several possible implementations of mixed-reality scenario testing, including different strategies for data mixing. The paper closes with twelve recommendations…
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Using Vehicle Specifications to Gain Insights into Different Automotive Market Requirements

Mahindra & Mahindra, Ltd.-Lemuel Paulraj, Saravanan Muthiah
  • Technical Paper
  • 2020-01-1283
To be published on 2020-04-14 by SAE International in United States
Determination of vehicle specifications (for example, powertrain sizing) is one of the fundamental steps in any new vehicle development process. The vehicle system engineer needs to select an optimum combination of vehicle, engine and transmission characteristics based on the product requirements received from Product Planning (PP) and Marketing teams during concept phase of any vehicle program. This process is generally iterative and requires subject matter expertise. For example, accurate powertrain sizing is essential to meet the required fuel economy (FE), performance and emission targets for different vehicle configurations. This paper analyzes existing vehicle specifications (Passenger Cars/SUVs - Gasoline/Diesel) in different automotive markets (India, Europe, US, Japan) and aims to determine underlying trends across them. Scatter band analysis is carried out for specifications such as vehicle kerb weight (WT), vehicle length (L), vehicle width (W), vehicle height (H), footprint area (FPA), engine cubic capacity (CC) and engine power (P). CC/WT vs FE, CC/FPA vs FE, P/WT vs FE, FPA/(LXW), CC/(FPAXH), FPAXH and WXH trends are analyzed amongst others. It is interesting to note that similarities exist…
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On Perception Safety Requirements and Multi Sensor Systems for Automated Driving Systems

Comentor AB-Jörgen Trygvesson
Qamcom Research and Technology AB-Anders Cassel, Carl Bergenhem, Ole Martin Christensen
  • Technical Paper
  • 2020-01-0101
To be published on 2020-04-14 by SAE International in United States
One major challenge in designing SAE level 3-5 Automated Driving Systems (ADS) is to define requirements for the perception system that would enable argumentation for safe operation. The safety requirements on the perception system can only be fulfilled through redundancy in the sensor hardware. It is, however, a challenge to specify the redundancy that is required in the sensor system. Safe operation for an ADS is significantly more difficult compared to advanced driver assistance systems (ADAS). The safety argumentation for ADAS typically argues that in case of a failure in the sensor array a fail-silent behavior is acceptable because the human driver can take control of the vehicle back. This argumentation however is not possible when developing level 4 or higher automation. This paper investigates prerequisites for applying a systematic methodology for analyzing redundancy in a multi-sensor system and the relation to a conceptual ADS functional architecture. This analysis must address the complexity that comes with partially overlapping sensor data from different sensors and considers variations in performance and characteristics due to changes in the…
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Balancing Lifecycle Sustainment Cost with Value of Information during Design Phase

CCDC Ground Vehicle Systems Center-Sam Kassoumeh, Monica Majcher, James Ealy, David Gorsich, Paramsothy Jayakumar
Oakland University-Vijitashwa Pandey
  • Technical Paper
  • 2020-01-0176
To be published on 2020-04-14 by SAE International in United States
The complete lifecycle of complex systems, such as ground vehicles, consists of multiple phases including design, manufacturing, operation and sustainment (O&S) and finally disposal. For many systems, the majority of the lifecycle costs are incurred during the operation and sustainment phase, specifically in the form of uncertain maintenance costs. Testing and analysis during the design phase, including reliability and supportability analysis, can have a major influence on costs during the O&S phase. However, the cost of the analysis itself must be reconciled with the expected benefits of the reduction in uncertainty. In this paper, we quantify the value of performing the tests and analyses in the design phase by treating it as imperfect information obtained to better estimate uncertain maintenance costs. A multi-attribute decision framework for military ground vehicles acquisition is employed to illustrate the methodology and the value of performing the analysis early in the system’s lifecycle. Attributes considered are maintenance cost and operational availability, while the utility is calculated for a risk averse decision maker. Numerical methods are employed to calculate the value…
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Leading Women in Engineering & Science: Maryam Zahabi, Assistant Professor of Industrial and Systems Engineering, Texas A&M University

  • Magazine Article
  • TBMG-36311
Published 2020-03-01 by Tech Briefs Media Group in United States

What led you to choose science and/or engineering as a career, particularly in the medical device field?

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SAE STANDARDS NEWS

Automotive Engineering: March 2020

  • Magazine Article
  • 20AUTP03_06
Published 2020-03-01 by SAE International in United States

SAE International and ISO, the International Organization for Standardization, announced in February 2020 the joint publication of a draft of a new Standard to address automotive cybersecurity engineering. The standard, ISO/SAE 21434, is designed to help industry define a structured process to ensure cybersecurity is incorporated into the design of road vehicles, including their components, subsystems, software and connections to external devices and networks.

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Leading Women in Engineering & Science: Mahsa Nakhjiri, Senior Director of Technical Product Management, Flex

  • Magazine Article
  • TBMG-36247
Published 2020-03-01 by Tech Briefs Media Group in United States