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The work presented here outlines the development of a robust CAO tool for optimal design of electromagnetic retarder machines. The developed EM-CAO tool is then used to perform a wide variety of CAE/CAO tasks, from automatically computing the torque versus rpm performance curves of the EM retarder to performing optimization. Two specific examples of optimal design of the EM retarder are reported. Through the use of a task manager/optimizer repetitive jobs are fully automated thereby making the analysis and optimization of electromagnetic retarders faster and user-friendlier.

Induction noise, which radiates from the open end of the engine air induction system, can be of significant importance in reducing vehicle interior noise and tuning the interior sound to meet customer expectations. This makes understanding the source noise critical to the development of the air induction system and the vehicle interior sound quality. Given the ever-decreasing development times, it is highly desirable to use computer-aided engineering (CAE) tools to accelerate this process. Many tools are available to simulate induction noise or, more generally, duct acoustics. The tools vary in degrees of complexity and inherent assumptions. Three-dimensional tools will account for the most general of geometries. However, it is also possible to model the duct acoustics with quasi-three-dimensional or one-dimensional tools, which may be faster as well.

A dynamic computer model of automotive air conditioning systems was developed. The model uses simulation software for the coding of 1-D heat transfer, thermodynamics, fluid flow, and control valves. The same software is used to model 3-D solid dynamics associated with mechanical mechanisms of the compressor. The dynamics of the entire AC system is thus simulated within the same software environment. The results will show the models potential applications in component and system design, calibration and control.

System integration is the path to successful entry of hybrid electric vehicle (HEV) technology into the marketplace. A modular solution capable of meeting varying customer requirements is needed. The controller must possess a flexible hierarchical architecture that insures cross-platform compatibility and provides adaptability for various engine, motor, transmission, and battery configurations. A hybrid powertrain supervisory controller (PSC) has been designed for an advanced parallel-type HEV prototype, which uses a continuously variable transmission (CVT). The controller schedules torque commands for the engine and motor and chooses the transmission ratio to meet driver demanded acceleration. The controller is organized around a state machine, which determines how best to employ powertrain components to satisfy the driver while maximizing fuel economy.

This paper gives an overview of a scalable engine management system architecture for motorcycle and other small engine based vehicle applications. The system can accommodate any engine sizes and up to four cylinders. The architecture incorporates advanced functionalities such as oxygen sensing, closed loop fueling, wall-wetting compensation, purge control, start & idle control and deceleration fuel cut-off. Additionally, a number of vehicle-related controls are integrated in the system. Diagnostic and safety related features have also been incorporated with limp-home capability. The software architecture is compatible with different hardware solutions. The system has been implemented in several OEM vehicles around the globe and meets EURO-3 emission requirements.

The purpose of this paper is to demonstrate our success in taking advantage of model-based development tools and auto-code technology to accelerate the typical life cycle development of powertrain software. In particular, we applied the technology as a clean sheet approach to Visteon's third generation Electronic Throttle Control system. In the process of applying model-based development and 100% auto-code, we identified various pitfalls and created solutions to overcome the gap between technology and development process during each phase of the entire software development life cycle. We will share our lessons learned during the requirement, design, implementation, and validation stages.

This paper discusses our experiences on the implementation and benefits of using the Hardware-In-the-Loop (HIL) systems for Powertrain control system software verification and validation. The Visteon HIL system integrated with several off-the-shelf diagnostics and calibration tools is briefly explained. Further, discussions on test automation sequence control and failure insertion are outlined The capabilities and advantages of using HIL for unit level software testing, open loop and closed-loop system testing, fault insertion and test automation are described. HIL also facilitates Software and Hardware Interface validation testing with low-level driver and platform software. This paper attempts to show the experiences with and capabilities of these HIL systems.

Determination of the critical speed of a driveshaft is critical for development and validation of its design for use in a vehicle because of its destructive effects. Typical calculations to determine critical speed are either over simplistic and not very accurate or very complicated requiring CAE software and capabilities. An analytical five-section non-prismatic beam model was developed to fill in this gap. The model was developed to compute the critical speed in a worksheet and proven to be as or more accurate as utilizing FEA methods. The model worksheet calculates the critical speed for one-piece conventional driveshafts and adapted for Visteon's Slip-In-Tube (SIT) driveshafts.

Realizing the value of knowledge, corporations are turning to Knowledge Based Engineering (KBE) as a design process. A fuel rail KBE tool was created at Visteon with the purpose of increasing knowledge retention and delivering knowledge based designs to the customer much quicker than with conventional methods. Currently, both engineers and CAD designers are using the Fuel Rail KBE Modeler at Visteon. It has been used on many vehicle programs and has saved the company countless person-hours of development time. The Fuel Rail KBE Modeler is a powerful tool that saves resources through automation of both the design and analysis processes. This paper documents the incorporation of automated FEA capability into the KBE environment.

This paper describes a front road wheel steer-by-wire system with two actuator motors on the rack and pinion assembly to move the road wheels. Dual actuators are used to provide actuator redundancy and to enhance the fault tolerance capability. When one actuator faults or fails, the other actuator is designed to work independently and maintain full system performance. The paper emphasizes control method to implement the motion control for the front road wheel steer-by-wire system with two actuators on the common load. The proposed dual servo synchronization motion control implements the angle tracking for the road wheel reference input by controlling two actuators synchronously and cooperatively. It includes two servo feedback control loops to track the common reference input. The angular position error between two feedback loops is compensated using a synchronized compensator.

Not all software tools are created equal and not all software tools are created to perform the same tasks. Therefore, different software tools are used to perform different tasks. However, being able to share the information between the different software tools, without having to manually re-enter (duplicate) any of the information, can save a lot of time and improve the quality of the product. The control software interface presented in this paper, allows system engineers to exchange data between software tools in an efficient manner which maximizes each tools capabilities and ultimately reduces development time and improves the quality of the product.

Same of the more enticing and productive opportunities to a useful work in product assurance are those of influencing the design of a product. The primary concern of design assurance is preventing or correcting those design errors that lead to poor product integrity. One of the tools used by the development teams in many organizations is the Design Review. The impact in cost and quality is directly affected by the correct utilization of the tool.

In order to facilitate the modeling of vehicle drivelines in ADAMS, an ADAMS/View driveline tool was developed with the aid of Mechanical Dynamics, Inc (MDI). Known as Visteon Axle & Driveline Simulation-Dynamics (VADSIM-DYNA) this tool is used to supply customers with driveline models for use in their full vehicle modeling as well as for predicting forces in the driveline. Of specific interest is a method for calculating the mesh point of a hypoid gear set using the geometry of the ring and pinion gears, and a custom force statement for calculation of the mesh point reactions at the center of gravity for both the pinion and ring gears. With the introduction of ADAMS/Driveline, The comapny has worked with MDI to implement VADSIM-DYNA into the base product. With the aid of VADSIM-DYNA the ability to provide customers with ADAMS models of driveline components and systems has been greatly enhanced.

Rising costs continue to be a problem within the automotive industry. One way to address these rising costs is through modularity. Modular systems provide the ability to achieve product variety through the combination and standardization of components. Modular design approaches used in development of vehicle electrical, electronic, and software (EES) systems allow sharing of architectures/modules between different product lines (vehicles). This modular design approach may provide economies of scale, reduced development time, reduced order lead-time, easier product diagnostics, maintenance and repair. Other benefits of this design approach include development of a variety of EES systems through component swapping and component sharing. In this paper, new optimization algorithms and software tools are presented that allow vehicle EES system design engineers to develop modular architectures/modules that can be shared across vehicle platforms (for OEMs) and across OEMs (for suppliers).

Steer-by-wire systems (SBW) offer the potential to enhance steering functionality by enabling features such as automatic lane keeping, park assist, variable steer ratio, and advanced vehicle dynamics control. The lack of a steering intermediate shaft significantly enhances vehicle architectural flexibility. These potential benefits led GM to include steer-by-wire technology in its next generation fuel cell demonstration vehicle, called “Sequel.” The Sequel's steer-by-wire system consists of front and rear electromechanical actuators, a torque feedback emulator for the steering wheel, and a distributed electronic control system. Redundancy of sensors, actuators, controllers, and power allows the system to be fault-tolerant. Control is provided by multiple ECU's that are linked by a fault-tolerant communication system called FlexRay. In this paper, we describe the objectives for fault tolerance and performance that were established for the Sequel.

GENPAD® is a knowledge-based, three-dimensional modeling computer tool developed by Visteon to create occupant-friendly interiors. GENPAD quickly and easily produces zones to evaluate ergonomic aspects of vehicle interiors such as reach, clearance, vision, and reflection. These zones are produced from automated design studies based on experience and engineering standards accepted by the automotive industry. Without GENPAD, a single study requires an experienced engineer 4-6 hours to complete. Multiple studies require several engineers weeks to perform. The methods used are also error-prone due to complex instructions. To overcome these challenges, GENPAD provides over 50 ergonomic packaging studies that produce accurate results in minutes, not weeks, every time.

A hydraulic steering pump system will be considered in this report. The objective is to improve the design of a specific power steering pump using computational fluid dynamics (CFD) tools. The first part of this report deals with a pump oil seal leak. The thermal and fluid environments have been simulated. A variable fluid viscosity is used, showing a 15-20% increase in peak temperature. Potential improvements in product design have been suggested. The second part deals with using computer tools to reduce redundant testing. This includes use of parametric approach towards optimization. A rotating grid approach (basic moving mesh technique) is used.

MBT timing for an internal combustion engine is also called minimum spark timing for best torque or the spark timing for maximum brake torque. Unless engine spark timing is limited by engine knock or emission requirements at a certain operational condition, there exists an MBT timing that yields the maximum work for a given air-to-fuel mixture. Traditionally, MBT timing for a particular engine is determined by conducting a spark sweep process that requires a substantial amount of time to obtain an MBT calibration. Recently, on-line MBT timing detection schemes have been proposed based upon cylinder pressure or ionization signals using peak cylinder pressure location, 50 percent fuel mass fraction burn location, pressure ratio, and so on. Because these criteria are solely based upon data correlation and observation, both of them may change at different engine operational conditions. Therefore, calibration is still required for each MBT detection scheme.

Manual ‘porting” of source code is often required in order to “reuse” control software in different applications with different target hardware. This process is not cost effective. Maintaining multiple “versions” of the same software also causes problems. This paper describes a way in which multiple target source code can be generated from a single model. A custom data class is developed so that it can be used to define both signal and parameter data types necessary for data dictionary-driven models. This capability allows a single model to be used to generate code for multiple target hardware architectures. A software development process using a generic model to support multiple hardware targets is compared with the hand porting process (e.g. floating-point to/from fixed-point). Auto code generation from a sample multi-target feature model will be presented. The efficiency of the auto code will also be discussed.

Stabilizer bars in a suspension system are supported with bushings by a frame structure. To prevent the axial movement of the stabilizer bar within the bushing, several new stabilizer bar-bushing systems have been developed. The new systems introduce permanent compressive force between the bar and the bushing thereby preventing the relative movement of the bar within the bushing. This mechanical bond between the bar and the bushing can eliminate features such as grippy flats, collars etc. In addition, by controlling the compression parameters, the properties of the bushing such as bushing rates can be tuned and hence can be used to improve the ride and handling performance of the vehicle. In this paper, nonlinear CAE tools are used to evaluate one such compressively loaded bushing system. Computational difficulties associated with modeling such a system are discussed.