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In recent years, one of the most important issues in the automotive industry is the improvement of fuel economy started from the environmental problem. Making cars lighter and reducing the coefficient of friction are two ways to improve fuel economy. Reducing the weight of a cylinder, an engine component, is a typical example. The traditional, mainstream method to reduce cylinder weight has been to convert cast iron cylinder blocks into aluminum cylinder blocks by using cast iron sleeves. To further make engines lighter and more compact, however, it is desirable that cast iron sleeves be abolished, or, in other words, making cylinder blocks sleeveless. A typical technology to make cylinder blocks sleeveless is applying anti- wear coating on a bore wall. Electroplating is currently the mainstream method used for this technology. It must be noted, however, electroplating is used primarily for low-pressure cast cylinders.

Suspension design is one of important technique to develop automobile. Since suspension system has strong non-linearity, it is difficult to optimize the suspension system by Gradient Based Method. Authors discussed the benefit of Genetic Algorithms to optimize the suspension system in this paper. Prototype of optimization system for suspension systems based on Genetic Algorithms was developed. In this system, the suspension system was analyzed and evaluated by Mechanical System Simulation Software ADAMS. The validity of the optimization system was clarified through the two case studies focusing on toe curve and lateral stiffness. Typical double wishbone type rear suspension with twenty design variables was analyzed and optimized by the optimization system.

The continuously variable damper is widely used in the semi-active suspension system since it can yield various damping forces at a given damper velocity. By applying an appropriate control scheme to the damper, satisfaction of both ride comfort and driving safety can be realized. For successful development of the semi-active suspension system, a model that accurately describes the complex and nonlinear behavior of the continuously variable damper is crucial. In this research, a modeling technique for the continuously variable damper has been studied. Various damper components have been analyzed and their effects upon damper characteristics have been closely investigated. The effects of the damper characteristics change upon ride comfort and driving safety has also been investigated via simulations.

There is a limit in expense and facilities to perform structural analysis by repeating crash tests using actual vehicles. This paper describes an example of crash analysis by FEM performed by our company, for frontal crash and rollover of a large-sized bus. Regarding the frontal crash analysis, firstly static collapse tests were performed using a scale model of the under-floor structure in order to get the deformation mode, then the structure was analyzed using an FE model. Secondly, an effectiveness of a full model that included the frame model was verified by a frontal crash test at 35km/h. Last, the structural improvement based on the full model was considered. Regarding the rollover analysis, since the event duration is long, a method to utilize partial body model instead of a complete vehicle was proposed in order to reduce calculation time. As practical results, the improved vehicle showed good performance satisfying the target level in frontal crash and rollover tests.

With developing technology, automobile has progressed a comfortable one and chassis control system related to this is studied vigorously. Suspension plays an important role as vibration suppression and handling. But the conventional passive suspension cannot improve those two simultaneously. Therefore it necessitates a demand on the several kinds of electronic-controlled suspensions. In this paper the design of sliding mode controller using singular perturbation method for 1/4 car semi-active suspension model is studied. Using singular perturbation method, the full order system is separated into slow subsystem related to sprung mass and fast subsystem related to unsprung mass. With this model reduction, sliding mode controller which is based on Lyapunoy theory is designed and applied to real system easily. Sliding mode control which is designed to be robust with changing system parameters is applied to slow subsystem.

A twist beam plays important roles in a trailing twist axle suspension. The cross-sectional configuration of the twist beam determines the performance of the suspension. The finite element (FE) analysis is usually utilized in order to evaluate the performance of this suspension. However, most automotive designers cannot directly perform the FE analysis because specific skills are required to achieve sophisticated operation. Moreover, the construction of the FE model also requires a large amount of time and task. In this paper, we propose a new methodology for the initial design of the trailing twist axle suspension in order to overcome these problems. This method includes (1) the interactive drawing operation for the cross-section, (2) the quick evaluation of the cross-sectional properties, and (3) the automatic construction of the twist beam stiffness matrix used in the kinematic analysis.

In order to minimize occupant injury in a vehicle crash, an approach was attempted to address this issue by making the wave form of vehicle body deceleration (deceleration curve) optimal to lower the maximum deceleration value applied to the occupant. A study with a one-dimensional, two-mass model was conducted to the kinetic mechanism between the body deceleration curve and the responding occupant''s motion while finding a mathematical solution for the optimal body deceleration curve. A common feature of the derived mathematical solutions is that they consist of three aspects: high deceleration, low or negative deceleration, and constant deceleration. This was demonstrated by simulation with a three-dimensional dummy. The results show that the response of the dummy closely agrees with that of the one-dimensional, two-mass model, thus proving the adequacy of the mathematical solution, and that occupant injury was reduced.

This paper will demonstrate the benefits of a small-team approach to the design of a high-profile, special-purpose vehicle intended to showcase the technology and abilities of a complete supplier network. Using traditional and latest technology methodologies, the project will be delivered on time and within budget to the complete satisfaction to all participants. The paper provides a brief review and history of the industry within the context of the topic and then gives a background to the aXcess Australia concept as it was applied to the Low Emission Vehicle. There is a confirmation that a mixture of techniques, both traditional and modern, can coexist and in fact provide better outcomes within a restricted budget and timeframe.

To simulate the car-to-car crash accidents in the real field, the Autonomous Driving System was developed. This system consists of communicating, sensing, accelerating, braking, steering and data recording subsystems. All these were designed to be compact, light and collapsible, so that the crash characteristics of test vehicle were not affected. The velocity performance of the system covers from 10 kph to 100 kph within ± 0.5 kph error, and the lateral deviation is constrained within ± 20 mm. With this system, several frontal offset and side car-to-car crash tests were carried out successfully. Deformations, injury levels, deceleration signals and dynamic behaviors during crash were typically investigated. And the dynamic behaviors were compared with the simulation results of EDSMAC. Car-to-car crash tests between small and large vehicles with different masses were carried out and the effects on the compatibility were investigated.

Mitsubishi Automotive Engineering Co., Ltd., gained ISO9001 certification for whole 9 sites of its own on Feb. 1999 with paperless system as first automotive engineering company in Japan, we think. In establishing the quality system conforming to ISO9001 requirements, we have newly developed and utilized Process Management System, i.e., "PMS" to control total R&D and service processes of the company. The unique points of PMS comparing with existing project managing tools are as follows. 1. PMS has clear and easy to understand "process management"; 2. functions, controlling responsible personnel, schedule, work standard and output of each process of the project; 3. PMS conforms very well to ISO9001 quality system requirements; 3. PMS works on Intra-Net web system being recognized by every person on the company web. PMS, combined with Intra-Net paperless documentation system, has given us the following merits. 1.

A bodywork roll attitude during cornering is not a simple rotary motion around the geometrical roll center. It is a complicated rotary motion including vertical motion under the influence of a lot of forces caused by suspension links and components. This motion affects not only vehicle dynamics, but also roll feeling evaluated by a driver. Therefore a vehicle roll attitude is recognized as one of factors to characterize the vehicle handling performance, and a suspension system is designed considering this point. Concerning the roll feeling, it is known that human being feels insecurity and discomfort toward "floating," and the vertical motion during cornering has a relationship with subjective ratings by a driver. Tis paper presents the roll attitude control theory "Virtual Damper Control (VDC)" considering above behavior, and confirms the effects by comparing with current anti-roll control.

Suspension plays an important role as a first gate to exterior environment. Especially suspension deals with vibration suppression and handling. But the conventional suspension cannot achieve those two simultaneously. Therefore it necessitates a demand on several kinds of electronic-controlled suspensions. Semi-active suspension has several advantages over the active suspension like low cost, low weight and easy maintenance. But it also has some disadvantages like being unable to do attitude control and small control range. To overcome disadvantages, new types of semi-active suspension is proposed which has two actuators, variable damper and variable air-spring. And an algorithm is presented which can synthesize and coordinate two actuators. To verify the effectiveness of the proposed system, simulations and tests have been conducted.

VADSIM-FEA is a comprehensive axle and driveline system finite element (FE) modeling tool developed by Visteon Chassis Axle & Driveline Strategic Business Unit (SBU). By incorporating the best Computer-Aided Engineering (CAE) Practices and SDRC IDEAS software, VADSIM-FEA serves as a user-friendly tool in creating complete driveline system FE models for the purpose of noise, vibration and harshness (NVH) and component structural analyses. The tool was successfully used to generate Independent Rear Suspension (IRS) driveline system FE models as well as its subassemblies resulting in more than 70% reduction in modeling time. VADSIM-FEA makes up-front CAE analyses more efficient in fulfilling VPDS (Visteon Product Development System) objectives.

Product development is a vital stage in manufacturing, and only if it is operated in a faster speed the competing level of the company will sustain. The term rapid comes into being to shorten any possible time frame of the manufacturing activities. Assuming that most modern manufacturing industries achieve similar productivity gain through their production facilities, then product development area is subject to economic rationalization. Due to its nature, time is mostly the main problem in handling product development to the market, and it will go accordingly beyond unbelievable spending throughout the time frame. Fortunately, under rapid concept, product development stage can be cut to the optimal time and so the cost and the product feature. This paper will be materialized by substantial research evidences of solving numerous cost reduction in product development of several cases in Indonesian automotive car industries mainly through Rapid Prototyping Solution.

Since changes in market trends occur faster compared to the past and the market itself has become extremely diversified, the production line in plants needs to feature higher levels of flexibility and agility. To achieve goals, one possible option is the use of a single-spindle ultra-high-speed machine with a parallel link mechanism, which would substitute the conventional multi-spindle machine. Multi-spindle-type machinery has been widely used in aluminum component machining/transferring facilities, including, among others, those for cylinder blocks and cylinder heads. To ensure the required production line flexibility, it is necessary to modify the machinery to minimize the investment and lead time for new model production. This paper reports on the background, target and structure of parallel link-type machinery.

Recent advances in the field of numerical modeling of unsteady reacting flows in the exhaust system of s.i. engines are presented in the paper. In particular, it is shown that the integration of a suitable chemical and thermal model for the catalytic converter within a 1D fluid dynamic simulation code has allowed the prediction of the exhaust gas composition from the cylinder to the tailpipe outlet, considering its variation across the catalyst. The composition of the exhaust gas, discharged by the cylinder, is calculated by means of a two- zone combustion model, including emission sub-models. The catalytic converter is simulated by a 1D fluid dynamic and chemical approach, considering laminar flow in each tiny channel of the substrate and chemical reactions in the solid phase, within the wash-coat. The predicted reaction rates are used to determine the specie source terms to be included in the one-dimensional fluid dynamic conservation equations.

Over the past few years, active suspension system on motor vehicles has had an in increasing application. The simulation of this system has a multiple importance, especially in the countries such as ours: We gain time - by not having to wait for exploitation results; It is cost-effective - we don't have to design an expensive model in the Lab and perform complex laboratory examinations; We can simulate suspension systems of almost all categories and kinds of motor vehicles, which could, also, be hardly possible in laboratory conditions. Suspension system modelling has been performed on ¼ vehicle model, using Matlab program, version 5.2, in two different ways: by transfer function and state-space equation. It has been concluded that the settling time and overshoot of the vehicle, after coming across any kind of obstacle, are too long, and that a controller must be introduced into the suspension system.

In this paper, a 2-DOF experimental equipment of active suspension is developed. This system is hydro-pneumatic type and is controlled through oil flow. A control strategy based on output feedback and frequency shaping is proposed and realized on this model. Output feedback can reduce the number of system states that should be measured and thus simplify the complexity and improve the reliability of the system. Because of the different human sensitivity to different frequency ranges of vibration, it is necessary to pay effort on the suppression of vibration according to human sensitivity. Frequency shaping technology is thus applied on performance index to improve the ride quality. Several types of measurement versions are investigated and optimized. Simulation results indicate that using sprung mass velocity and suspension deflection, the system performance can approach the full-state feedback system performance.

The purpose of this paper was to introduce a new predicting method of chest acceleration developed by using numerical approach. In order to predict chest acceleration, the proposed method used two input data, which were chest restraint stiffness and vehicle pulse from actual test. The effectiveness of the method as verified by comparing the difference between original chest acceleration and the predicted one using same vehicle pulse and chest restraint stiffness. Predicted chest acceleration for the 50 kph test by using the data of 56 kph test was found to be in good agreement with chest acceleration of actual test for both belted only and bag and belted test cases. This new predicting method was utilized in parameter study of restraint slope(k) and belt slackness.

Determination of human tolerance to injury is difficult because of the physical differences between humans and animals, dummies and cadaver tissue. Certain human volunteer testing has been done but at subinjurious levels [STAP 86] [EWIN 72] Considerable biomechanical engineering injury studies exist for the adult human cadaver however little is available for the pediatric population [SANC 99] [KLEI 98b]. Studies have been made of pediatric skull bone modulus, fetal tendon and early pediatric studies of the newborn during delivery, however, a paucity of information still exists in these areas. A number of dummies have recently been made available principally for airbag testing to bridge the gap between the 50 percentile Hybrid III male dummy and the 95 percentile male dummy.