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Vehicle target setting is an evolving process based on continually changing internal (management, standards) and external (competitive and legal) requirements. In addition to evolving requirements, the process for establishing and documenting targets may not be clear. The objective of this paper is to detail the overall process of target setting, the critical factors to consider, and key definitions for each stage of the process. It will describe the complete process from early competitive benchmarking to final verification testing. Setting targets for a vehicle requires definition and thorough benchmarking of the competition, an understanding of the key attributes used to describe the vehicles' performance, and a clearly defined set of requirements. These requirements will be regulatory, corporate and competitively based and grouped by clearly defined, customer perceived attributes which can be cascaded to specific vehicle systems.

Lookup tables and functions are widely used in real-time embedded automotive applications to conserve scarce processor resources. To minimize the resource utilization, these lookup tables (LUTs) commonly use custom data structures. The lookup function code is optimized to process these custom data structures. The legacy routines for these lookup functions are very efficient and have been in production for many years. These lookup functions and the corresponding data structures are typically used for calibration tables. The third-party calibration tools are specifically tailored to support these custom data structures. These tools assist the calibrators in optimizing the control algorithm performance for the targeted environment for production. Application software typically contains a mix of both automatically generated software and manually developed code. Some of the same calibration tables may be used in both auto generated and hand-code [ 1 ] [ 2 ].

Current road vehicles have tendency of use softer suspension springs to improve ride comfort, but as a moving device with suspension system, vehicles have other parts that can affect attributes for comfort perception, and is necessary the correct definition of which one should be modified to address the comfort issue and avoid impact in attributes for stability. Usually springs are not the main responsible for bad comfort behavior, but shock absorbers and bushings are. A typical passenger car shows a wide possibility of loads carriage and how to set up correctly the suspensions considering its tradeoffs and brand DNA is the main issue.

With the introduction of new technologies ranging from developing new alternative energy vehicles to passive and active safety systems, the automakers are responding to the increased complexity of the control system by embracing Model Based Design (MBD) and Auto-code Generation (ACG) tools for control system design. This translates into lower development costs, higher quality and faster time-to-market. The Ford Motor Company production hybrid group launched a pilot project to study the feasibility of using MBD to speed up the development and testing of the next generation Torque Monitor software. This software uses a custom data storage format, called Double Store Variable (DSV) format, for all the critical signals. Each variable contains two fields, one for storing the actual data and the second for storing a transformed copy (e.g. one's complement) of the data. This allows the software to detect run-time corruption of the data in real-time.

The Indirect Boundary Element Analysis is employed for developing a computational pass-by noise simulation capability. An inverse analysis algorithm is developed in order to generate the definition of the main noise sources in the numerical model. The individual source models are combined for developing a system model for pass-by noise simulation. The developed numerical techniques are validated through comparison between numerical results and test data for component level and system level analyses. Specifically, the source definition capability is validated by comparing the actual and the computationally reconstructed acoustic field for an engine intake manifold. The overall pass-by noise simulation capability is validated by computing the maximum overall sound pressure level for a vehicle under two separate driving conditions.

In an effort to improve the quality of software and take advantage of Lessons Learned, Ford Motor Company has created a generic list of software requirements to help prevent software design errors, mistakes and faults from being delivered to our customer in our vehicles. Ford's intent of publishing these requirements is to provide a basis for an SAE Recommended Practice. Ford's goal is to encourage the software community to participate in the development of a recommended practice that can benefit all software developers. These particular requirements were developed for Automotive Body Features.

The development of embedded systems in automotive environment has brought a strong expansion in the number of applications dependent of programmable devices. A failure in any of these systems may cause different types of damages. Therefore, it requires a high confidence in their operation. Many of these faults are inserted during the coding process. A tool for formal verification of the implemented code could allow the detection of possible errors that could not be encountered during the testing phase. In this paper, we propose a method for verifying software from the reduced model of the software built automatically with information from multiple traces of program executions. To illustrate the application of the proposed method a case study for an automotive electronic module that controls the windshield wiper is presented.

The objectives of this study were a) to determine how expert judges categorized valid Integrated Vehicle-Based Safety Systems (IVBSS) Forward Collision Warning (FCW) events from review of naturalistic driving data; and b) to determine how consistent these categorizations were across the judges working in pairs. FCW event data were gathered from 108 drivers who drove instrumented vehicles for 6 weeks each. The data included video of the driver and road scene ahead, beside, and behind the vehicle; audio of the FCW alert onset; and engineering data such as speed and braking applications. Six automotive safety experts examined 197 ‘valid’ (i.e., conditions met design intent) FCW events and categorized each according to a taxonomy of primary contributing factors. Results indicated that of these valid FCW events, between 55% and 73% could be considered ‘nuisance alerts’ by the driver.

A highly adaptable fatigue testing computer system is presented for controlling single or multichannel test machines. The system imposes most common varieties of waveforms and also provides time synchronization between channels, such as in the case of variable amplitude biaxial load histories, and monitors various feedback signals for both data acquisition and alarm purposes. The program operates in a real-time Unix system as a separate stand-alone process. Communication with other users or the operator is done only through a reserved common block of shared memory. This feature allows control and monitoring of all tests over the computer network. A user can simply login remotely and check the test or start a data acquisition task from any workstation in the company, and then take the data files and analyze them on other computers. This paper describes the operation of the software, the methodology behind the hardware selection and the software structure.

This paper considers some aspects of the use of linear elastic FE analysis as a basis for durability calculations. It specifically considers problems that can be treated as quasi-static and describes the use of inertia relief. However, much of the discussion is also applicable to situations that can better be represented as dynamic. It provides guide-lines for FE modelling for durability analyses including the requirements for mesh quality and for load and boundary condition definition. It also describes a novel way of looking at surface stress information, and reviews some of the methods of getting from linear elastic FE stresses and load histories to realistic elastic-plastic stress and strain histories.

This paper presents a description of intelligent sensor-based manufacturing, reviews previous research in this area, and identifies control system requirements necessary to support successful application of this technology. Current production control systems inhibit the successful implementation of advanced manufacturing control technologies. It is often difficult, if not impossible, to integrate new sensing technologies and advanced control algorithms with existing control platforms. To address this difficulty, hardware and software needs to support intelligent sensor-based manufacturing are discussed.

It is frequently useful to calculate the theoretical composition of the major components of vehicle exhaust. A software program has been written in Basic (or Quick Basic) which allows the convenient calculation of volume percents of CO, CO2, O2, H2, and H2O from fuel composition (H/C and O/C ratios), the water content (dew point) of the combustion air, and a chosen stoichiometry (air/fuel ratio). The program considers the Water Gas Shift reaction and the production of hydrogen under fuel rich conditions. The program is valid for both standard gasolines and oxygenated blends. Vehicle emissions data, collected to compare values calculated by the program with actual experimentally determined values from vehicle exhaust, show good agreement for measurements made at a series of air/fuel ratios ranging from lambda of 0.85-1.2.

Designing a high-quality door sealing system at low cost is an economic and technological engineering challenge. Robust design is a systematic and efficient technique to meet this challenge of design optimization for performance, quality, and cost. This technique, also called parameter design, focuses on making product and process designs insensitive (i.e. robust) to hard-to-control variations called noise factors. In this paper, we illustrate and apply the principles of robust design using a response model approach to a door sealing system design problem where vehicle interior sound is the primary response being studied. The Appendix contains a glossary of all italicized words for reference.

In the last few years, there has been a considerable number of applications of microcomputer based systems in the automotive industry. Such systems have advantages in discriminating the signal from the EMI/RFI noise, through software techniques. This paper will explain how easily a system can be affected by EMI/RFI interference and briefly discuss some microprocessor software techniques on possible noise discriminating applications.

The objective of this paper is to illustrate an interactive computer graphics program developed to simplify the creation of finite element data which will be used for computerized structural analysis. Three-dimensional, part definition data in the form of basic design lines is input to the program and displayed on a cathode ray tube, and then a structural engineer creates the finite element definition using various computer graphics techniques. The procedures involved are discussed in detail, as well as the advantages over the traditional manual approach to element generation. Actual experience has demonstrated that this interactive computer graphic approach, in addition to being both accurate and reliable, is approximately fifteen times faster than the tedious manual method.

A Microcomputer Based Eight Channel Data Acquisition System has been developed for customer correlation and routine vehicle field testing applications. The eight channel system includes a self-contained signal conditioning system designed for a variety of transducer types and data frequency requirements. Calibration, signal gain, and channel zero offset adjustments can be performed under software control. The microcomputer system is based on a Motorola M6800 microprocessor and a non-volatile core memory module. The paper describes the design, development, field performance, and data processing characteristics of the system and presents specific automotive applications and field test results.

Many new driver information features are being added to today’s vehicles. This paper addresses the utility of these features to the customer and the functional parameters which must be specified in order to assure optimum performance of these features.

This paper gives a comprehensive analysis of vehicle understeer-oversteer, utilizing theoretical and experimental approaches. It departs from the conventional by defining understeer-oversteer in the transient as well as in the steady-state condition under various types of inputs. The relationship between understeer-oversteer and directional and oscillatory stability is stated within this concept. The paper introduces new definitions, based on transient condition analysis, for direct and indirect understeer, directional and oscillatory stability, side-slip velocity, and others. It employs a computer program evolved from the equations of motion, shown in the comprehensive Appendix, to analyze the basic nature of understeer-oversteer. New procedures are outlined for quantitative determination of vehicle understeer and stability. The paper discusses the relationships between understeer, oscillatory stability, and the subjective “feel” of passenger automobiles.

Today's electronic instrumentation is almost completely dominated by the microprocessor. Most standard techniques used to protect against electromagnetic interference have been ineffective. This paper presents a design method which allows immunity to higher levels of interference through the synergistic use of hardware and software.

The 1984 Continental Mark VII electronic instrument cluster is reviewed with emphasis on the software algorithm used to store the odometer value in the non-volatile memory. The algorithm, through the use of multiple storage locations, parity checks, and relationship checks, increases the integrity and reliability of the non-volatile memory and minimizes the loss of distance associated with partial memory failures. The criteria and rationale used to develop the algorithm is discussed along with a brief description of the operation of the algorithm.