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Network communications are widely being deployed in vehicle electrical architecture due to its low cost for embedded electronic and advance it provides. Nowadays, different types of protocols may be used to allow the communication among the modules (e.g.: CAN, LIN, FLEX RAIL, etc). Modules may receive or send data throughout a physical layer. And they are powered up by using different types of cables, grounds and shields which create a high complexity in terms of wiring harnesses installation, weight and cost. Data and power transmission throughout a unique line is a real and promising available technology.

Vehicle dynamics CAE capabilities has increased in the past few years, specially, for handling and steering attributes. However, secondary ride simulations are still highly depended on the tire model. Such tire model must be capable to simulate high order phenomenon such as impact and harshness transmissibility in three directions. In order to gather tire information sufficient to cope with these phenomena, one needs to perform a series of specific tests, and so be able to build the intended tire model. Still, there could be correlation issues. This whole process takes a lot of time and resources. This article presents a semi-analytical approach, using data gathered via wheel force transducers (WFTs) that are typically used for load cascading and durability purposes. The method main advantage is that since it relies on measured data at the wheel center, it is independent of a tire model, and, as such, it demands less time and resources.

Since the technology applied to vehicles is constant increasing, new systems are being developed to improve performance, comfort and safety. The main way to improve safety is to keep the driver informed about unsafe traffic. In this paper we propose the development of an algorithm that works with an Antilock Brake System, in order to keep the driver informed about the distance between the vehicle equipped with this system and another one in front of it, by this way there is more time to make a safe breaking. The interaction between the driver and this method is given by a visual alert system.

Brake system development and testing is spread over vehicle manufacturers, system and component suppliers. Test equipment from different sources, even resulting from different technology generations, different data analysis and report tools - comprising different and sometimes undocumented algorithms - lead to a difficult exchange and analysis of test results and, at the same time, contributes to unwanted test variability. Other studies regarding the test variability brought up that only a unified and unambiguous data format will allow a meaningful and comparative evaluation of these data and only standardization will reveal the actual reasons of test variability. The text at hand illustrates that a substantial part of test variability is caused by a misinterpretation of data and/or by the application of different algorithms.

Noise source identification has been a subject well studied in the past few years. Automobile manufactures along with specialized supplies have been developed some methods in this matter. The importance of such subject is quite obvious, especially in the auto industry: identify potential problems and point out solutions for NVH. There are several methods of noise source identification widely used. Among them, one can mention "Hotspot Search," which consists of noise intensity measurement, mapping and ranking the relative contribution of each substructure of one body. Another method used, one can point out is the STSF (Spatial Transformation of Sound Fields). It consists of a measurement over a scan plane using a set of microphone array. In this way, a 2D sound field can be transformed in a 3D description and source direction can be identified.

From the brake system point of view the world can be split into comfort and performance markets. This market split evolved historically and reflects local legal requirements, driving style and the customer expectations. Noise, cold judder and brake dust play the dominant role in the perception of the customer on the comfort market. The performance markets call for high friction level and good fade performance. Currently these customer needs can only be satisfied by usage of different pad materials: NAO and Semi Met materials for comfort markets and generally Low Met materials for performance markets. Due to the differences mentioned above, additional brake system development and testing is done (different testing locations for the same brake attribute). Harmonizing testing, usage of the same test location and same test method could save not only the human resources but also decrease the number of prototypes used in the development phases.

Front road wheel toe dynamics directly affects tire wear and steering wheel vibration, which in turn negatively impacts customer satisfaction. Though static toe can be preset in assembly plants, the front road wheels can vibrate around steering axes or kingpin axes due to tire mass unbalance and nonuniformity. The frequency of the vibration depends on the wheel size and vehicle speed, while the amplitude of the vibration is not only dictated by the tire forces, but also by suspension and steering parameters. This paper presents a study on the sensitivities of the front road wheel toe dynamics to the parameters of a short-long-arm suspension (SLA) and a parallelogram steering system. These parameters includes hard point shift, steering gear compliance, gear friction, control arm bushing rates, friction in control arm ball joints, and compliance in tie rod outboard joints.

Ford recently introduced an industry first Modular Hybrid Transmission (MHT) in the Model U concept vehicle at the 2003 North American International Auto Show. The MHT is a full function hybrid system (i.e. capable of electric drive) that utilizes a modular approach to leverage high volume conventional driveline components to create a lower-cost hybrid system [1]. In the MHT, the torque converter of a conventional automatic transmission is removed and in its place is packaged a single high voltage electric machine and an engine disconnect clutch. Advanced controls are used to enable hybrid functions. A critical element in the development of the MHT is the ability to replicate the functions of the torque converter without compromise to the vehicle drivability. In this paper, the control of four transmission functions in the MHT will be discussed: 1) transmission engagement, 2) vehicle launch, 3) power-on up-shift and 4) coast downshift.

Ford's H2RV is a Hydrogen engine propelled Hybrid Electric concept Vehicle that was unveiled and driven at Ford's Centennial Show in June 2003. This vehicle is an industry first by an OEM that demonstrates the concept and the marriage of a HEV powertrain with a supercharged Hydrogen ICE that propels the vehicle. Just as Model T was the car of the 20th century, Model U is the vehicle for the 21st century. The powertrain utilizes compressed gaseous hydrogen as fuel, a supercharged 2.3L internal combustion engine, a 25 kW traction motor drive, the electric converterless transmission, regenerative braking, an advanced lithium ion battery, electric power assist steering, electronic throttle and Vehicle System Controller (VSC). The vehicle could deliver a projected fuel economy of 45 mpg and near zero emissions without compromise to performance.

In recent times, the development of alternate-fuel vehicles, including those fueled by hydrogen, has become relatively common. While there are potential safety related issues with any combustible fuel, these have been resolved over the last 100+ years. The comfort level with gasoline fuel has resulted from the widespread application of simple safety procedures followed at every stage of gasoline refinement and handling. It is important to have analogous procedures for handling hydrogen-fueled vehicles safely and with confidence. The characteristics of hydrogen, including: a) wide flammability range, b) very low ignition energy, c) odorless and difficult to detect, d) high diffusion rate, e) high buoyancy, f) invisible flame, etc., bolster the need for safe practices and procedures.

Ford's H2RV (Hydrogen Hybrid Research Vehicle) uses a Hydrogen fueled Internal Combustion Engine. This engine has a higher compression ratio and a faster fuel-burning rate compared to a conventional gasoline engine. The conventional flywheel is replaced with an electric motor in the hybrid powertrain, which causes higher crankshaft torsionals and is a major NVH source. The engine has a centrifugal supercharger mounted on its front-end dress, which is a big source of NVH. Fans are used to cool the high voltage batteries and to provide ventilation of H2 in the case of a leakage. The body sheet metal has several holes for passive H2 ventilation, battery cooling, plumbing lines, and harness routing. Underhood hardware, due to the hybrid transmission and the H2 ICE, created major packaging challenges for the intake and FEAD NVH. The exhaust muffler volume was limited due to the installation of high voltage batteries and underbody H2 fuel tanks.

North American drivers particularly dislike wheel dust (brake dust on their wheels). For some vehicle lines, customer surveys indicate that wheel dust is a significant concern. For this reason, Ford and its suppliers are investigating the root causes of brake dust and developing test procedures to detect wheel dust issues up-front. Intuitively, it would appear that more brake wear would lead to more wheel dust. To test this hypothesis, a gage was needed to quantitatively measure the wheel dust. Gages such as colorimeters were evaluated to measure the brightness (L*) of the wheel, which ranged from roughly 70-80% (clean) to 10-20% (very dirty). Gage R&R's and subjective ratings by a panel of 30 people were used to validate the wheel dust gages. A city traffic vehicle test and an urban dynamometer procedure were run to compare the level of wheel dust for 10 different lining types on the same vehicle.

This paper presents the development of a hardware in the loop (HIL) simulation system for evaluating and optimizing the interactions of the brake system with the vehicle. This unique HIL set-up consists of an inertial brake dynamometer with a brake corner module, an electronic control unit, a real time 3D total vehicle model and a computer system with a high-speed operating platform. The HIL system simultaneously confers advantages of both computer modeling and hardware testing. It offers the capability to do upfront design and assess performance of the foundation brake hardware and the chassis controls, as well as their interactions, in advance of testing and tuning a vehicle. This powerful tool enables reduction in development time and cost. A simple example of applying the brake dynamometer HIL system will be presented.

The extensive use of rotative machines in the diverse branches of the modern world has made the rising undesirable mechanical and acoustic vibration levels to be a problem of special importance for the machines normal operation as for the communities that are each time more affected by the problem. It makes the study of vibration and acoustic phenomena also to be even more important and the applications of its concepts more sophisticated. Several are the concepts used for decreasing vibration levels, like common dampers, hydraulic dampers, active dampers, natural frequencies changes and others. The choice of use of one or another depends greatly on the engineering possibilities (weight, energy, physical space, other components functional interference, vibration levels, etc.) as well as the cost of implementation of each one.

There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.

Some communication buses are too powerful and expensive for simple digital on/off operations such as activating lights, wipers, windows, etc. For these applications the LIN bus is currently the most promising communication protocol across the world's automotive industry. This paper addresses a study using LIN (Local Interconnect Network) for Ford South America vehicles. This will propose a new electrical architecture designed with LIN network, which will be replacing the conventional rear and front lights cables in Trucks, where other higher protocols, such as CAN, are not cost effective. LIN is a new low cost serial communication system intended to be used for distributed electronic system that will allow gaining further quality enhancement and cost reduction on cables, connectors and switches.

The NVH perception of a vehicle customer is the sum of contributions from various forces and its paths, structure and airborne. Each contribution is the product of an input force and body sensitivity. The tactile and acoustic transfer functions measurements determine how much of the input forces will reach to the costumer. Input points are suspension systems, powertrain and exhaust attachment points. Equivalent stiffness of these points is also determined on this test. This metric is used on target settings or to optimize body structure design at an early stage.

The driver judges his vehicle based on subjective aspects. Vehicle dynamics characteristics including ride and handling have a major impact on this evaluation. For this reason, vehicle manufactures have grown investments in order to improve vehicle dynamics behavior. Subjective evaluation and customer satisfaction research show which dynamic characteristics need to be improved. CAE models, after being validated based on experimental measures, give a good insight on vehicle dynamic behavior and guide change proposals. At end, new subjective evaluations and measures are carried out in order to check the real improvement of CAE proposals. This work shows the use of the described methodology for a pickup vehicle dynamics evaluation. One of the major complains of pickup drives is related to ride quality. Thinking of that feature the evaluation process considers several phenomena, such as abruptness, front topping, front bottoming, head toss and rear aftershake.

Two combined four-bar mechanisms have two functions: lift and collapse. In the current design, high effort was found for the collapse function. Axiomatic Design was used to analyze and optimize the current design. The customer domain was mapped into the functional domain by specifying customer needs in terms of functional requirements (FRs) and constraints (Cs). Design parameters (DPs) were identified in the physical domain for each functional requirement. Design matrices were then defined to characterize the product design. The two combined four-bar mechanisms have two functional requirements at the highest level: lift and collapse. The corresponding DPs are: lift four-bar linkage and collapse four-bar linkage. Through zigzagging to decompose to the next level, the design was found to be coupled. At this level, a torsion spring was selected as the DP for minimizing the lift effort.

In this paper we describe the development and application of a CAE methodology to investigate stresses incurred in the torque converter anti-rattle spring subjected to various static and dynamic loading conditions. The objectives of this study are three-fold. First, develop and demonstrate a dynamic modeling methodology suitable for torque converter rattle analysis. Second, provide insight into the underlying physics in the hardware design and identify key parameters to achieve high-mileage improvement, and third, recommend feasible design and manufacturing parameters for design improvements. Anti-rattle springs have been widely used in torque converter clutch to reduce rattle noise between the spline interface of the cover plate and the piston plate. They are constantly subjected to static and dynamic stresses under various vehicle operation conditions.