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Analytical methods are used extensively in the automotive industry to validate the feasibility of component and assembly designs and their dynamic behavior. Correlation of analytical models with test data is an important step in this process. This paper discusses the Finite Element model of an innovative Slip-in-Tube Propshaft design. The Slip-in-Tube joint (slip joint) poses challenges for its dynamic simulation. This paper discusses the methods of simulating the joint and correlating it to experimental results. Also, the Noise and Vibration (NVH) characteristics of the Slip-in-Tube Propshaft design. In this paper, a Finite Element model of the proposed propshaft is developed using shell and beam element formulations. Each model is verified to optimize the feasibility of using accurate and computationally efficient elements for the dynamic analysis.

Touch screens provide substantial benefits as a control and display system but still have some disadvantages. The availability of haptic (tactile) technology allows touch screens to function similarly to traditional mechanical controls. Two studies were undertaken to investigate the addition of haptic feedback as well as auditory feedback on user perceptions of the touch screen experience. The first study was conducted in a desktop setting and the second study was conducted with the touch screen integrated in a vehicle. In both studies, participants assessed four different types of feedback conditions: visual feedback only (V), auditory and visual feedback (AV), haptic and visual feedback (HV), and auditory, haptic, and visual feedback combined (AHV). The results of these studies support the claim that individuals strongly prefer touch screen implementations that incorporate haptic elements and also provide insights on regional differences in their perception.

A twenty-five kilowatt (peak power for one minute), permanent magnet electric machine for a hybrid electric vehicle application was designed and tested. The electric machine is located in the clutch housing of an automatically shifted manual transmission and is subjected to 120 °C continuous ambient temperatures. The package constraints and duty cycle requirements resulted in an extremely challenging thermal design for an electric machine. The losses in the machine were predicted using models based on first principles and the heat transfer in the machine was modeled using computational fluid dynamics. The simulations were compared to test results over a variety of operating conditions and the results were used to validate the models. Parametric studies were conducted to evaluate the performance of potting materials and cooling topologies.

This paper discusses the development of combination vehicle stability program (CVSP) at Visteon. It will describe why stability control is needed for combination vehicles and how the vehicle stability can be improved. We propose and evaluate controller structures and design methods for CVSP. These include driver's intent identification, combination vehicle status estimation and control, and fault detection / tolerance. In this paper, the braking and steering dynamics of car-trailer and tractor-semitrailer combinations, and the brake systems which should be used extensively to increase the stability of combination vehicles are presented. Also our development platform is introduced and the combination vehicle simulation results are presented. The definition of combination vehicles in this paper includes car-trailer and commercial tractor-semitrailer combinations since their vehicle dynamics are based on the same equations of motion.

Modern automobiles utilize stabilizer bars to increase vehicle roll stiffness. Stabilizer bars are laterally mounted torsional springs which resist vertical displacement of the wheels relative to one another. A stabilizer bar is constructed in such a way that it will meet package constraints and fatigue requirements. In order to design a robust stabilizer bar, Taguchi's “Design of Experiment method” is used. The objective of this paper is to develop a robust stabilizer bar design that will maximize the fatigue life and the roll stiffness while minimizing weight. This study is based on results obtained by CAE analysis.

The starter drive clutch is a one way roller clutch and a key component in a starter motor that is used to crank internal combustion engines. The starter drive clutch transmits torque from an electrical motor to a ring gear mounted on a cranking shaft in an engine thus cranks the engine. The clutch also prevents the whole starter from damage caused by extremely high load and/or extremely high speed applied to the starter pinion from the engine. Drive slippage and barrel cracking are two major failure modes for the starter drive[1]. Insufficient torque capacity results in drive slippage while excessive high hoop stress on the clutch barrel ring causes barrel crack. To eliminate drive slippage failure, the clutch should be designed with high torque capacity. High torque capacity, however, is a cause of high hoop stress on the barrel that may result in the cracked barrel failure. Higher torque capacity and lower hoop stress are two completely opposite design directions.

Occupant knee impact simulations are performed in the automotive industry as an integrated design process during the course of instrument panel (IP) development. All major automakers have different categories of dynamic testing methods as part of their design process in validating their designs against the FMVSS 208 requirement. This has given rise to a corresponding number of knee impact simulations performed at various stages of product development. This paper investigates the advantages and disadvantages of various types of these knee impact simulations. Only the knee load requirement portion of the FMVSS208 is considered in this paper.

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.

This paper describes two studies; each conducted concurrently in North America and Europe to assess subjective impressions and simulated driving task performance using a touch screen interface with different types of auditory and haptic feedback. The first study investigated subjective impressions of four types of touch screen feedback in a static laboratory setting. The second study investigated the influence of the same four touch screen feedback types on simulated driving task performance using the lane change test (LCT). Results of the first study revealed significant similarities and differences in subjective impressions between respondents in each of the two regions studied. Results of the second study revealed differences in task performance that suggest distinct participant strategies in each of the two regions studied.

Environmental concerns and changes in regulations around the world are turning mass-production electric vehicles (EVs) a reality. While the average driver is very familiar with the instruments available for the current internal combustion engine vehicles (ICEVs), the same does not hold for EVs. They require unique gages and tell-tales (also known as warning lights), tailored to their architecture, operating modes and intended use. This paper makes a comparison of the instruments used in ICEVs and EVs, suggesting a minimum set and standardization of the associated symbols.

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.

The stand alone oil to air (OTA) transmission cooling strategy with thermostatic cold flow bypass valve has been shown to be an effective means of improving the warmup of an automatic transmission. Improving the system warmup rate of an automatic transmission significantly improves its efficiency by reducing losses resulting from extremely viscous transmission fluid and can allow for calibration changes that improve overall transmission performance. Improved transmission efficiency in turn allows for improved engine efficiency and performance. The improvements obtained from increased transmission and engine efficiency result in an overall increase in vehicle fuel economy. Fuel economy and consumption are important parameters considered by the vehicle manufacturer and the customer. Fuel economy can be considered as important as reliability and durability.

A fixed-base driving simulator with a 14-degree of freedom vehicle dynamics model was used to compare the lane tracking performance of test subjects using a joystick steering controller to that using a conventional steering wheel. Three driving situations were studied: a) straight-line highway driving, b) winding road driving (country road), and c) evasive maneuvering - a double lane change event. In addition, three different joystick force-feedback settings were evaluated: i) linear force feedback, ii) non-linear, speed sensitive force feedback and iii) no force feedback. A conventional steering wheel with typical passenger car force feedback tuning was used for all of the driving events for comparison.

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.

Automotive gear oil development has expanded beyond the historical requirements of emphasizing wear protection to encompass modern needs for fuel economy and limited slip frictional properties. This paper describes the development process of a new generation, fuel efficient gear lubricant for use in light duty vehicles. A systematic formulation approach was used, encompassing fluid viscometrics and additive optimization. Performance testing in both laboratory and vehicle tests is described. Though standard GL-5 tests were used to confirm oxidation, wear and corrosion performance, emphasis is given to those methods used for optimizing fuel economy.

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.

This paper introduces the Driver Stability System (DSS) at Visteon. DSS is a new active comfort / safety system for automobiles which controls the seat bolsters independently in real time to enhance the lateral support of the occupants. Under turning maneuvers, DSS reacts to the vehicle dynamics to provide an increased contact area between the occupants and their seats, allowing optimal occupant location with respect to such variables as steering wheel angle, lateral acceleration, yaw rate, and vehicle velocity. The lateral force compensation is directly coupled to the dynamic movement of vehicle chassis and the change of road profile. The system consists of the seat bolster assembly including DC motors, wheel speed sensors, steering wheel sensor, lateral accelerometer, yaw rate sensor, and electronic control unit (ECU). This paper also discusses the control concept of DSS and its realistic controller structure.

The paper addresses compressor body temperature (crankcase) importance to the vehicle AC system long-term durability. Majority of OEM vehicle test evaluation is to see if AC system can pass compressor discharge temperature and discharge pressure targets. Most OEMs adopt 130°C max compressor discharge temperature and 2350 kpag head pressure as the target. From the field, although some of the compressor failure results from a high compression ratio, and compressor discharge temperature that are caused by the poor front end airflow, etc., high percentage compressor failed systems exhibit not too high compression ratio and compressor discharge temperature, but having the trace of high temperature in the shaft area, gasket area, etc. With introducing more and more variable swash plate compressor applications, OEMs start to see more and more compressor failures that are not related to a high compressor discharge temperature but the trace of high compressor body temperature.

A stabilizer bar in a suspension system is useful for preventing excessive rolls in vehicle maneuvers like cornering. Stabilizer bars are supported with bushings by either a frame or a subframe. To prevent the axial movement of the stabilizer bar within the bushing, features like add on collars, upset rings, grippy flats etc. are used on the stabilizer bar. At Visteon Corporation, several new stabilizer bar - bushing systems are developed where such axial movement is prevented by the use of compressive force. Relative merits of different stabilizer bar - bushing systems are compared in terms of roll stiffness and maximum stress on the bar through the use of finite elements.

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.