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The Kinematic Analysis Methods Computer Program that has been used by Ford Motor Co. to evaluate mechanisms for the past four years has been modified to generate performance curves for windshield wiper linkages directly using a Calcomp Plotter. Problems such as stalling, “jerky” operation, and excessive phase lag between wipers can be detected early in the design stages by careful evaluation of the curves.

Automotive outside rear view mirror shape has become an important consideration in achieving wind noise and aerodynamic performance objectives. This paper describes a two step process used to develop a mirror shape which meets both wind noise and aerodynamic objectives. First, basic understanding of door mounted verses sail mounted mirrors and shape parameters was obtained by evaluating selected shapes and studying their physical measurements relative to their measured responses. Relationships between the wind noise and drag responses revealed performance range limitations for sail mounted mirrors. Second, a central composite experimental design was utilized to more closely investigate door mounted mirror shape parameters to determine optimal mirror performance potential. The resulting empirical models developed were used to determine the best overall solution.

A laboratory wear test is used to evaluate the wear protection properties of new and used engine oils formulated for FFV service. Laboratory-blended mixtures of these oils with methanol and water have also been tested. The test consists of a steel ball rotating against three polished cast iron discs. Oil samples are obtained at periodic intervals from a fleet of 3.0L Taurus vehicles operating under controlled go-stop conditions. To account for the effects of fuel dilution, some oils are tested before and after a stripping procedure to eliminate gasoline, methanol and other volatile components. In addition to TAN and TBN measurements, a capillary electrophoresis technique is used to evaluate the formate content in the oils. The results suggest that wear properties of used FFV lubricants change significantly with their degree of usage.

The present study investigates the wave propagation and attenuation in catalytic converters. The relationships for wave propagation in a catalytic monolith are derived first and then coupled to the wave propagation in tapered ducts. Analytical predictions are compared with experimental results to validate the theory.

AS a basis for the analyses of this symposium, a hypothetical car has been used to evaluate the engine power distribution in performance. Effects of fuel,-engine accessories, and certain car accessories are evaluated. The role of the transmission in making engine power useful at normal car speeds is also discussed. Variables encountered in wind and rolling resistance determinations are reevaluated by improved test techniques. Net horsepower of the car in terms of acceleration, passing ability and grade capability are also summarized.

A piezoelectrically driven vibrating cantilever blade is damped by a number of mechanisms including viscous damping in a still fluid and aerodynamic damping in a flow. By measuring the damping of devices operating at resonance in the 1 to 5 kHz region, one can measure such properties as mass flow, absolute pressure or the product of molecualar mass and viscosity. In the case of the mass flow measurement, the device offers a mechanical alternative to hotwire and hot film devices for the automotive application.

In the present paper, we introduce a drivetrain system using an electromagnetic coupling for hybrid electric vehicles, and propose a new control concept of vibration torque interception. The electromagnetic coupling is an electric machine that is composed of a pair of rotors, and electromagnetic torque acts mutually between the rotors. In the drivetrain system, the electromagnetic coupling works as a torque transmission device with a rotational-speed-converting function. We demonstrate that, by using this control, the electromagnetic coupling also works as a damping device that intercepts the vibration torque of the internal combustion engine, while transmitting the smooth torque to its drive line. Using a model of a two-inertia resonance system, a control system is designed such that a transfer function representing input-to-output torque is shaped in the frequency domain.

Generally, automobiles have many performance requirements for comfort, of which noise, vibration and harshness are very important. Toyota Motor Corporation equipped several 2003 models with the second-generation Electronically Controlled Brake system (ECB2). These ECB2 actuator units adopted a new structure that reduced pumping noise by controlling the skew phenomena of needle roller bearings. Normally, needle roller bearings are advantageous over other bearings in cases where a large force is loaded on bearings, because the contact areas can be made larger. However, a thrust force arises from skew phenomena because of minute clearances among the component parts of needle roller bearings. As a result, axial vibration of the bearing shaft sometimes occurs due to the thrust force. This paper explains how the thrust force generated from the skew phenomena of needle roller bearings occasionally affects the pumping vibration level of equipped machinery such as the brake actuator unit.

This paper presents a new application of a vehicle on-board battery charger utilizing high frequency Silicon Carbide (SiC) power devices. SiC is one of the most promising alternatives to Silicon (Si) for power semiconductor devices due to its superior material characteristics such as lower on-state resistance, higher junction temperature, and higher switching frequency. An on-board charger prototype is developed demonstrating these advantages and a peak system efficiency of 95% is measured while operating with a switching frequency of 250 kHz. A maximum output power of 6.06 kW results in a gravimetric power density of 3.8 W/kg and a volumetric power density of 5.0 kW/L, which are about 10 times the densities compared with the current Prius Plug-In Si charger. SiC technology is indispensable to eco-friendly PHV/EV development.

A prototype power control unit (PCU) was manufactured using silicon carbide (SiC) power semiconductors (diodes and transistors), which have low power loss when switching on and off. This PCU was installed in a hybrid vehicle (HV) and driven on a test course and chassis dynamometer. The test results confirmed a fuel efficiency improvement of about 5 percent.

Toyota Motor Corporation (TMC) began a wireless charging field test in February 2014. A wireless charging system was installed at the residences of test subjects with the aim of identifying issues related to convenience and installation in daily usage. The test vehicle was fabricated by installing a wireless charging system into a Prius PHV (Plug-in Hybrid Vehicle). The installed system had the same charging power as the cable charging system used on the base vehicle, and had a charging time of 1.5 hours. A high-frequency 85 kHz power supply and primary coil were produced for the charging infrastructure. To identify differences in charging behavior, the test subjects were asked to use the cable charging system for the first month before changing to the wireless charging system for two months. Data acquisition was performed by an on-board data logger and through interviews with the test subjects.

A series of tests have been performed on a production vehicle to determine the characteristics of the external turbulent flow field in wind tunnel and road conditions. Empirical formulas are developed to use the measured data as source levels for a Statistical Energy Analysis (SEA) model of the vehicle structural and acoustical responses. Exterior turbulent flow and acoustical subsystems are used to receive power from the source excitations. This allows for both the magnitudes and wavelengths of the exterior excitations to be taken into account - a necessary condition for consistently accurate results. Comparisons of measured and calculated interior sound levels show good correlation.

This paper proposes a technology to reduce vehicle surge during towing that utilizes motors and shifting to help ensure comfort in a parallel HEV pickup truck. Hybridization is one way to reduce fuel consumption and help realize carbon neutrality. Parallel HEVs have advantages in the towing, hauling, and high-load operations often carried out by pickup trucks, compared to other HEV systems. Since the engine, motor, torque converter, and transmission are connected in series in a parallel HEV, vehicle surge may occur when the lockup clutch is engaged to enhance fuel efficiency, similar to conventional powertrains. Vehicle surge is a low-frequency vibration phenomenon. In general, the source is torque fluctuation caused by the engine and tires, with amplification provided by first-order torsional driveline resonance, power plant resonance, suspension resonance, and cabin resonance. This vibration is amplified more during towing.

The development of electric vehicles has been progressed, rapidly, to achieve Carbon neutrality by 2050. There have been increasing concerns about Electromagnetic Compatibility (EMC) performance due to increasing power for power trains of vehicles. Because same power train system expands to some vehicles, we have developed numerical simulations in order to predict the vehicle EMC performances. We modeled a vehicle which has inverter noises by numerical simulation to calculate electric fields based on GB/T18387. We simulated the common mode noise which flows through the shielding braid of the high voltage wire harnesses. As a result, it is confirmed a correlation between the electric fields calculated by numerical simulation and the measured one.

This paper presents the extended Kalman filter-based sideslip angle estimator design using a nonlinear 5DoF single-track vehicle dynamics model with stochastic modeling of tire forces. Lumped front and rear tire forces have been modeled as first-order random walk state variables. The proposed estimator is primarily designed for vehicle sideslip angle estimation; however it can also be used for estimation of tire forces and cornering stiffness. This estimator design does not rely on linearization of the tire force characteristics, it is robust against the variations of the tire parameters, and does not require the information on coefficient of friction. The estimator performance has been first analyzed by means of computer simulations using the 10DoF two-track vehicle dynamics model and underlying magic formula tire model, and then experimentally validated by using data sets recorded on a test vehicle.

The dynamic characteristics of a vehicle are an important part of the driver's experience. Ford Motor Company is actively pursuing a leadership role in this arena. To achieve this goal, all the necessary information to complete the vehicle dynamics picture of a vehicle must be gathered in an efficient and well-organized manner. A process was developed to fingerprint a vehicle so that this information could drive vehicle tuning, new Computer Aided Engineering (CAE) models, correlate existing CAE models, support problem resolution and conduct target setting. This paper will discuss a Vehicle Dynamics Fingerprint Process in detail and explain the steps involved.

This paper describes an investigation into the sound quality of passenger car and light truck closure sounds. The closure sound events that were studied included side doors, hoods, trunklids, sliding doors, tailgates, liftgates, and fuel filler doors. Binaural recordings were made of the closure sounds and presented to evaluators. Both paired comparison of preference and semantic differential techniques were used to subjectively quantify the sound quality of the acoustic events. Major psychoacoustic characteristics were identified, and objective measures were then derived that were correlated to the subjective evaluation results. Regression analysis was used to formulate models which can quantify customers perceptions of the sounds based on the objectively derived parameters. Many times it was found that the peak loudness level was a primary factor affecting the subjective impression of component quality.

Recent advances in morphing, simulation, and optimization technologies have enabled analytically driven aerodynamic shape optimization to become a reality. This paper will discuss the integration of these technologies into a single process which enables the aerodynamicist to optimize vehicle shape as well as gain a much deeper understanding of the design space around a given exterior theme.

Trivalent chromate coating is replacing the conventional hexavalent chromate coating applied on zinc plating. Zinc plating uses one of three types of plating baths (zincate, cyanide and chloride) according to the characteristics required of subject parts. It has been recognized that trivalent chromate coating provides different corrosion resistance depending on the type of zinc plating bath used. Zinc plating with chromate coating were analyzed to clarify the cause of the corrosion resistance variation with the type of zinc plating bath. It has been revealed that the chromate coating thickness and the condition of top SiO2 layer vary with the type of zinc plating bath, resulting in corrosion resistance variation.

Intake and exhaust valve control has been combined with engine calibration control by an on-board computer to achieve a Variable Displacement Engine with improved BSFC during part throttle operation. The advent of the on-board computer, with its ability to provide integrated algorithms for the fast accurate flexible control of the entire powertrain, has allowed practical application of the valve disabler mechanism. The engine calibration basis and the displacement selection criteria are discussed, as are the fuel economy, emissions and behavior of a research vehicle on selected drive cycles ( Metro, Highway and Steady State ). Additionally, the impact upon vehicle driveability and other related subsystems ( e.g., transmission ) is addressed.