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The two-dimensional, frictional tyre-road contact interaction is investigated. A transient contact algorithm is developed, consisting of an analytical belt model, a non linear sidewall structure and a discretized viscoelastic tread foundation. The relationship between the magnitude/shape of the predicted two-dimensional pressure distribution and the corresponding belt deformation is identified. The effect of vertical load and the role of sidewall non linearity are highlighted. The modal expansion/reduction method is proposed for the increase of the computational efficiency and the effect of the degree of reduction on the simulation accuracy is presented. The qualitative results are physically explained through the participation of certain modes in the equilibrium solution, offering directions for the application of the modal reduction method in shear force oriented tyre models.

Biomechanical surrogates are used in various forms to study head impact response in automotive applications and for assessing helmet performance. Surrogate headforms include those from the National Operating Committee on Standards for Athletic Equipment (NOCSAE) and the many variants of the Hybrid III. However, the response of these surrogates to loading at the chin and how that response may affect the loads transferred from the jaw to the rest of the head are unknown. To address part of that question, the current study compares the chin impact response performance of select human surrogates to that of the cadaver. A selection of Hybrid III and NOCSAE based surrogates with fixed and articulating jaws were tested under drop mass impact conditions that were used to describe post mortem human subject (PMHS) response to impacts at the chin (Craig et al., 2008). Results were compared to the PMHS response with cumulative variance technique (Rhule et al., 2002).

The paper presents a study on the prediction of wear for systems in which progressive wear affects the operating conditions responsible for the wear. A simple slider-crank mechanism with wear occurring at one of the joints is used to facilitate the study. For the mentioned mechanism, the joint reaction force responsible for the wear is, itself, affected by the progression of wear. It is postulated that the system dynamics and the wear are coupled and evolved simultaneously. The study involves integrating a dynamic model of the slider-crank mechanism (with an imperfect joint) into a wear prediction procedure. The prediction procedure builds upon a widely used iterative wear scheme. The accuracy of the predictions is validated using results from an actual slider-crank mechanism.

Drilling compound hole is very common material processing operation in engineering industry. In this special machining process before drilling the hole the part is rotated about an auxiliary axis parallel to one of the reference axes. Accuracy of the drilled hole is paramount in several applications such as in cylinder head and some other applications of bone surgery. Inaccuracy in hole axis may result in the loss of engine efficiency in the case of Cylinder Head or unsuccessful bone surgery. In the previous papers Murty et al. [8], [9] the algorithms developed had restricted application. In the first paper the tool was restricted to move in vertical plane and WY-plane was considered as reference plane. In the second paper the tool movement was unrestricted in space but the WY-plane was considered as reference plane and the skew error was assumed only in WY-plane.

While adult head injuries have been studied over the past six decades, few studies have investigated pediatric head injury mechanics. This paper presents non-injurious head accelerations during various activities in a pediatric population. Six males and six females aged 8–11 years old were equipped with a validated head sensor package and head kinematics were measured while performing a series of playground-type activities. Maximum resultant values across all participants and activities were 25.7 g (range 3.0 g to 25.7 g), 16.0 rad/s (range 10.4 rad/s to 16.0 rad/s), and 1705 rad/s2 (range 520 rad/s2 to 1705 rad/s2) for linear acceleration, angular velocity, and angular acceleration, respectively. Mean maximum resultant values across all participants and activities were 9.7 g (range 2.1 g to 9.7 g) and 734 rad/s2 (range 188 rad/s2 to 734 rad/s2) for linear and angular acceleration, respectively.

This paper discusses the effects of changes in specimen geometry, stress gradient, and residual stresses on fully-reversed constant amplitude uniaxial fatigue behavior of a medium carbon steel. Axial fatigue tests were performed on both flat and round specimens, while four-point rotating bending tests were performed only on round specimens. All the tests were performed using shot peened and unpeened flat and round samples, to investigate the effects of compressive residual stresses on fatigue behavior. The specimens in the rotating bending tests experienced longer life for a given stress amplitude than in the axial test. Shot-peening was found to be beneficial in the long life region, while in short life tests the shot-peened samples experienced a shorter life than the unpeened samples under both axial and bending test conditions.

Smart Touch® sensing is a breakthrough in human interface technology allowing direct access to computer power, such as with the highly successful iPhone™ and other handheld devices. By combining the reliability and flexibility of completely solid state sensing along with anthrotronic considerations, capacitive sensing interface technology creates new automotive design opportunities. Consumers are increasingly turning to touch screen devices for their ease of use. Touch screens enable designers to dramatically improve the automotive interior for (1) user satisfaction (2) OEM cost benefits (3) important safety/ergonomic benefits and (4) styling design freedom to harmonize with interior themes. Panels will not only act on touch, but will have functions that respond to hand gestures and movements. For example, a center stack console can be enabled to illuminate when the user makes a movement near it, with the added benefit of conserving power.

Knowledge mapping is a first and mandatory step in creation of system architecture. This paper considers the conceptual modeling of automotive systems, and discusses the creation of a knowledge-based model with respect to the Object Process Methodology an approach used in designing intelligent systems by depicting them using object models and process models. With this knowledge, systems engineer should consider what a product is comprised of (its structure), how it operates (its dynamics), and how it interacts with the environment. As systems have become more complex, a prevalent problem in systems development has been the number of accruing errors. A clearly defined and consistent mapping of knowledge regarding structure, operation and interaction is necessary to construct an effective and useful system. An interactive, iterative and consistent method is needed to cope with this complex and circular problem.

There are 30 million people in remote, rural communities in China without access to electricity. The government of China has initiated an ongoing effort to provide constant, reliable power to these citizens. Renewable energy is being utilized to solve this problem, which necessitates the use of a storage medium for energy, because renewable energies (i.e. wind and/or solar power) are inherently intermittent, variable, and largely unpredictable. By storing excess energy when it is plentiful (for a maximum feasible time of two days) and distributing it to the community in times of scarcity, the intermittent power is effectively leveled and auxiliary power is provided. A high-inertia flywheel was designed for this application because of its simplicity, ease of maintenance, low cost, and reliability. This design addresses many problems including bearing losses, aerodynamic losses, and distribution losses. The proposed design consists of a six spoke layout with a large outer ring.

The reliability of engine valve springs is a very important issue from the point of view of warranty. This paper presents a combined experimental and statistical analysis for predicting the fatigue limit of high tensile engine valve spring material in the presence of non-metallic inclusions. Experimentally, Fatigue tests will be performed on valve springs of high strength material at different stress amplitudes. A model developed by Murakami and Endo, which is based on the fracture mechanics approach, Extreme value statistics (GUMBEL Distribution) and Weibull Distribution will be utilized for predicting the fatigue limit and the maximum inclusion size from field failures. The two approaches, experimental and theoretical, will assist in developing the S-N curve for high tensile valve spring material in the presence of non-metallic inclusions.

From a quarter to one half of all projects that fail to meet their imperatives of cost, performance/quality or schedule are in some way associated with missing, poorly written or misunderstood requirements (1). This results in re-design, re-test and continual frustration to both the originator and the user of these requirements. Thus, a process for generating complete, consistent, unambiguous and verifiable requirements is essential to today’s automotive development process which focuses on “fast to market” and “doing it right the first time.” Lessons learned from evaluating the customer, internal and supplier requirements specifications show that the following requirement deficiencies regularly occur – Hidden Incomplete or unclear Incorrect Ambiguous Missing Unknown Secret (competitive sensitive) Unknown Correlations.

Aerodynamic noise generated in a miniature car had been evaluated using numerical simulation. Large Eddy Simulation (LES) was applied to analyze the transient flow field and the Ffowcs Williams-Hawkings (FW-H) acoustic analogy was employed to conduct acoustic analysis. The time accurate flow data was obtained using a finite volume flow solver on an unstructured grid. The flow field around the rear view mirror was obtained by numerical for two cases with different side view mirrors. Moreover, the distribution of acoustic source was predicted on side windows, and the aerodynamic noise was lowed through optimizing the shape of the rear view mirror and some experiments were done to validate the effect. Present study ascertained the feasibility and applicability of finite volume method (FVM) with SGS model towards prediction of aerodynamic noise generated in production vehicle.

Today’s car manufactures inevitably have to focus on the reduction of fuel consumption while maintaining high performance standards. In this respect, the downsized turbocharged DISI (Direct Injection Spark Ignition) engine represents an appealing solution. However, downsizing is limited because of knocking phenomena occurring at high- and full-load conditions due to autoignition of the unburned mixture ahead the flame front. A common way of reducing knock tendencies is provided by Exhaust Gas Recirculation (EGR). However, EGR modifies the chemical composition of the cylinder charge and recirculated species like nitric oxide (NO) or unburned Hydrocarbons (HC) particularly increase the reactivity of the unburned mixture. In other words, the EGR influences the Octane Number (ON) of the in-cylinder gases.

A newly developed small-sized IES (inductive energy storage) circuit with semiconductor switch at turn-off action was successfully applied to an ignition system. This IES circuit can generate repetitive nanosecond pulse discharges. An ignition system using repetitive nanosecond pulse discharges was investigated as an alternative to conventional spark ignition systems. Experiments were conducted using spherically expanding flame configuration for CH4 and C3H8-air mixtures under various conditions. The ignition system using repetitive nanosecond pulse discharges was found to improve inflammability of lean combustible mixtures, such as extended flammability limits, shorted ignition delay time, with increasing the number of pulses. The authors seek for the mechanisms for improving the inflammability in more detail to optimize ignition system, and verify the effectiveness of IES circuit in EGR condition, for real engine use.

A lightweight body sealer that cures at low temperatures was developed. In order to make the sealer lightweight, it is necessary to add light raw materials. In this development, the technique in which the weight reduction effect adds the resin balloon which is high and is easy to fluctuate the thickness and the particle diameter of shell was selected. Two types of resin balloons were used in combination with each other. High pressure-resistant resin balloons made of polyacrylonitrile (PAN) were one type, of which pressure resistance was increased by optimally designing heat-expandable microspheres (raw material), and the other type was high pressure-resistant polyester (PES) balloons. To enable the sealer to cure at low temperatures, it is necessary to use a resin that cures in the specified temperature zone and has the necessary physical properties.

This paper is a discussion of topics presented by the author at the Panel Session “Evaluation of Studies on Non-Deterministic Approaches (NDA) for Complex Systems” at the 2007 SAE World Congress. The emphasis herein is on issues in conducting model based reliability assessments, by combining verification and validation (V&V) of the model with a process compatible with traditional reliability assessments conducted as part of Reliability Based Design Optimization (RBDO). Formulations are presented and simplified to isolate each of the terms in V&V, and make each term compatible with subsequent RBDO while still accommodating non-deterministic design situations. The paper concludes with overall issues regarding V&V and Reliability, and compares this combined method with some other methods in use in the community and discussed at a follow-on SAE panel in 2008.

Accounting for more than 90% of the molecules and more than 75% of the mass [1], hydrogen is the most abundant element in the universe. Due to the small molecule size and high buoyancy, it is not available in it’s free form on Earth. In recent years, hydrogen has gained the attention of the automotive industry [2–12] as an environmentally friendly alternative fuel. As a fuel, hydrogen is unique - it is odorless, colorless, tasteless, and burns invisibly in sunlight. Detection solutions such as the odorants used in natural gas are not yet feasible for automotive hydrogen because the available additives can poison the fuel cell catalyst. Additionally, the lower flammability limit of hydrogen is lower, and the flammability range wider, than fuels such as gasoline [13]. Hydrogen detection and its concentration measurement is usually done using hydrogen concentration sensors [13].

This paper presents an experimental calibration method for the feedforward fuelling controller for a PFI SI engine. A recently proposed method [1] is extended from the idle to the torque delivery region and uses a Riccati designed rather than Parameter-Space linear element. Dynamic input signals are applied to air path, load and fuel entering the engine to excite the air-to-fuel ratio dynamics. A nonlinear inverse compensator is obtained directly from the observed input-output behaviour. Least squares black-box identification is used to generate the compensator using an algebraic NARX structure. The resulting inverse compensator not only acts as the feedforward controller but also linearises the fuelling path and therefore makes the system well suited for robust linear feedback control. The feedforward compensator is experimentally demonstrated and subsequently a robust H-infinity feedback controller is designed, implemented and the complete system experimentally validated.

This paper presents a robust controller design method for improving vehicle lateral stability and handling performance. In particular, the practical load variation will be taken into account in the controller synthesis process such that the controller can keep the vehicle lateral stability and handling performance regardless of the load variation. Based on a two-degree-of-freedom (2-DOF) lateral dynamics model, a model-based Takagi-Sugeno fuzzy control strategy is applied to design such a controller and the sufficient conditions for designing such a controller are given in terms of linear matrix inequalities (LMIs) which can be solved efficiently using currently available numerical software. Numerical simulations are used to validate the effectiveness of the proposed control approach.

The full vehicle simulation on durability proving grounds is a well established technique in the development process of passenger car manufacturers. The respective road surfaces are designed to generate representative spindle loads and typically include events that will result in large tire deformations. Depending on manufacturer and the combination of vehicle size and wheel properties, these deformations can be so large that the tire belt and/or sidewall have contact with the rim crown (protected by the tire sidewall). The current tendency to low-aspect ratio tires reduces the available deformation capability of the tire while simultaneously introducing larger nonlinearities in the sidewall behavior. After a short overview of the standard modeling technique used by the CDTire model family to handle such events, a refinement of this technique is introduced, modeling both the non-linearity behavior of the sidewall and a possible subsequent rim contact.