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In this paper, we propose algorithms for cost minimization of physical wires that are used to connect electronic devices in the vehicle. The wiring cost is one of the most important drivers of electrical architecture selection. Our algorithms perform wire routing from a source device to a destination device through harnesses, by selecting the optimized wire size. In addition, we provide optimized splice allocation with limited constraints. Based on the algorithms, we develop a tool which is integrated into an off-the-shelf optimization and workflow system-level design tool. The algorithms and the tool provide an efficient, flexible, scalable, and maintainable approach for cost analysis and architecture selection.

This paper presents the most recent advancement in the vehicle development process using the one-step or auto Transfer Path Analysis (TPA) in conjunction with the superelement, component mode synthesis, and automated multi-level substructuring techniques. The goal is to identify the possible ways of energy transfer from the various sources of excitation through numerous interfaces to given target locations. The full vehicle model, consists of superelements, has been validated with the detailed system model for all loadcases. The forces/loads can be from rotating components, powertrain, transfer case, chain drives, pumps, prop-shaft, differential, tire-wheel unbalance, road input, etc., and the receiver can be at driver/passenger ears, steering column/wheel, seats, etc. The traditional TPA involves two solver runs, and can be fairly complex to setup in order to ensure that the results from the two runs are consistent with subcases properly labeled as input to the TPA utility.

In the vehicle development process, one important step is to set a component performance target from the vehicle level performance. Conventional barrier-decoupler dash mats and floor trim underlayment systems typically provide sound transmission loss (STL) with minimal absorption. Thus the performance of such components can be relatively easily specified as either STL or Insertion Loss. Lightweight dissipative or multi-layered acoustic materials provide both STL and significant absorption. The net performance is a combination of two parameters instead of one. The target for such components needs to account for this combined effect, however different suppliers use unique formulations and manufacturing methods, so it is difficult and time consuming to judge one formulation against another. In this paper, a unique process is presented to set a component target as a combined effect of STL and absorption.

Evaluation of one year of in-use operating data from first generation Chevrolet Volt Extended-Range Electric Vehicle (E-REV) retail customers determined trip initial Internal Combustion Engine (ICE) starts were reduced by 70% relative to conventional vehicles under the same driving conditions. These Volt drivers were able to travel 74% of their total miles in EV without requiring the ICE's support. Using this first generation Volt data, performance of the second generation Volt is projected. The Southern California Association of Governments (SCAG) Regional Travel Survey (RTS) data set was also processed to make comparisons between realistic PHEV constraints and E-REV configurations. A Volt characteristic E-REV was found to provide up to 40 times more all-electric trips than a PHEV over the same data set.

Wire shorts on an in-vehicle controller area network (CAN) impact the communication between electrical control units (ECUs), and negatively affects the vehicle control. The fault, especially the intermittent fault, is difficult to locate. In this paper, an equivalent circuit model for in-vehicle CAN bus is developed under the wire short fault scenario. The bus resistance is estimated and a resistance-distance mapping approach is proposed to locate the fault. The proposed approach is implemented in an Arduino-based embedded system and validated on a vehicle frame. The experimental results are promising. The approach presented in this paper may reduce trouble shooting time for CAN wire short faults and may enable early detection before the customer is inconvenienced.

Partially automated driving involves the relinquishment of longitudinal and/or latitudinal control to the vehicle. Partially automated systems, however, are fallible and require driver oversight to avoid all road hazards. Researchers have expressed concern that automation promotes extended eyes-off-road (EOR) behavior that may lead to a loss of situational awareness (SA), degrading a driver’s ability to detect hazards and make necessary overrides. A potential countermeasure to visual inattention is the orientation of the driver’s glances towards potential hazards via cuing. This method is based on the assumption that drivers are able to rapidly identify hazards once their attention is drawn to the area of interest regardless of preceding EOR duration. This work examined this assumption in a simulated automated driving context by projecting hazardous and nonhazardous road scenes to a participant while sitting in a stationary vehicle.

AUTOSAR(AUTomotive Open System ARchitecture) establishes an industry standard for OEMs and the supply chain to manage growing complexity to the automotive electronics domain. Increased focus on software based features will prove to be a key differentiator between vehicle platforms. AUTOSAR serves to standardize automotive serial data communication protocols, interaction with respect to hardware peripherals within an ECU and allow ECU implementer to focus on development of unique customer focused features that distinguish product offerings. Adoption strategy and impact assessment associated with leveraging AUTOSAR for an E/E Architecture and the potential challenges that need to be considered will be described in this publication. This publication will also illustrate development strategies that need to be considered w.r.t deploying AUTOSAR like data exchange, consistency to BSW software implementation, MCAL drivers etc.

Automotive radars and cameras form the backbone of self-driving cars, Active safety and Advanced Driver Assistant Systems (ADASs). Streaming sensor, camera and audio data between sensors and Electronic control units(ECUs) requires huge data exchange. Ethernet with its large bandwidth capability is typically used as physical medium to communicate large data in automotive in-vehicle networks. Large data generally deals with payload size greater than single Ethernet Maximum Transmission Unit(MTU) size i.e.1522 Bytes that shall be sent via the transport protocol of the underlying bus. The purpose of the paper is to compare four different methods for transferring large data for current automotive Ethernet requirements. The methods Udp/Ip Fragmentation, Application fragmentation, Tcp/Ip Fragmentation and IEEE1722 transport protocol are evaluated. Bench evaluation of these methods are performed using Vector/Elektrobit software.

Time-critical applications in automotive are distributed across multiple Electronic control units (ECUs) that are connected through different in-vehicle networks. The ECUs on network protocols (CAN, Ethernet, FlexRay) operating at different source clocks needs to be synchronized to achieve time sensitive functionalities. Currently CAN and Ethernet have their own synchronization mechanisms. In a mixed architecture, challenge is to synchronize nodes on different protocols connected via gateway. AUTOSAR describes concept called Time gateway for such applications. This paper describes how time gateway can be configured for synchronizing nodes on CAN and Ethernet Networks. The approach is evaluated using bench simulation configured through Vector/Elektrobit software. The outcome of the method is to measure accuracy of synchronization between two nodes.

In automotive noise control, the hood liner is an important acoustic part for mitigating engine noise. The random incidence absorption coefficient is used to quantify the component level acoustic performance. Generally, air gaps, type of substrate materials, density of the substrate materials and Air Flow Resistivity (AFR) of the cover scrim are the dominant control factors in the sound absorption performance. This paper describes a systematic experimental investigation of how these control factors affect flat sample performance. The first stage of this study is full factorial measurement based on current available solutions from sound absorber suppliers. The acoustic absorption of different hood liner constructions, with variations in materials, density, air gaps, and scrims was measured.

The need for improved vehicle energy efficiency has increased greatly in recent years along with regulatory fuel economy standards. One key aspect of energy efficiency for both conventional and alternative propulsion vehicles is the energy efficiency of the electrical architecture. In the design of electrical architectures there are several techniques available to increase the energy efficiency. One technique is to manage CAN serial data communication by using Partial Networks. This paper describes a model based approach for simulating the vehicle network behavior when CAN Partial Networking is used as the strategy for need based ECU activation. The simulation results will in turn provide ECU power consumption data to support various electrical architecture design decisions.

Rapidly increasing customer, financial, and regulatory pressures are creating clear changes in the calculus of vehicle design for modern automotive OEM's (Original Equipment Manufacturers). Customers continue to demand shorter product lifecycles; the increasingly competitive global market exerts pressure to reduce costs in all stages of development; and environmental regulations drive a continuous need to reduce mass and energy consumption. OEM's must confront these challenges while continuing to satisfy the customer. The foundation to meeting these challenges includes: (1) Continued development of objective metrics to quantify performance; (2) Frontloading vehicle design content and performance synthesis; (3) A precise understanding of the customer and their performance preferences under diverse usage conditions. These combined elements will enable products better optimized amongst competing (and often contradictory) imperatives.

Emission compliance at the production level has been a challenge for vehicle manufacturers. Diesel oxidation catalyst (DOC) plays a very important role in controlling the emissions for the diesel vehicles. Vehicle manufacturers tend to ‘over design’ the diesel oxidation catalyst to ‘absorb’ the production variations which seems an easier and faster solution. However this approach increases the DOC cost phenomenally which impacts the overall vehicle cost. The main objective of this paper is to address the high variation in CO tail pipe emissions which were observed on a diesel passenger car during development. This variation was posing a challenge in consistently meeting the internal product requirement/specification.

This technical paper aims to provide a framework for simulating the thermal behavior of an automotive electrical connector with the current flow across each terminal. An automotive electrical connector uses multiple terminals fitted in the respective cavity of a connector. Temperature at terminal increases with the current flow level across it. This temperature rise occurs due to resistive heat loss in the terminal. Due to this, temperature in the surrounding cavities also rises; hence, the current carrying capacity of those cavities reduces. Analysis of similar scenarios for design alternatives and design decisions is important to develop reliable and optimized solutions. The reliable and optimized solution helps to save the cost. There is a large variation of different terminals used in the wiring harness, and there are various parameters attributing to this variation (shape, size, material, plating etc…).

A GT-Power Fast Run Model simplified from detail model for HIL is verified with a bench test using the dSPACE Simulator. Firstly, the conversion process from a detailed model to FRM model is briefly described. Then, the spark timing, fuel pulse with control for FAR, and torque level control are developed for proof of concept. Moreover a series of FRM/Simulink co-simulation and HIL tests are conducted. In the summary, the test results are presented and compared with GT detailed model simulations. The test results show that the FRM/dSPACE HIL stays consistent in most variables of interest under 0.7-0.9 real-time factor condition between 1000 - 5000 RPM. The same steady-state can be reached by RCP controllers or with GT-Power internal controllers. The transient states are close using different control algorithm. The main purpose of HIL application is achieved, despite inconsistencies in performance data like fuel consumption.