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As part of the development of a New SAE Recommended Practice for Brake Natural Frequency and Damping Measurements, the US Working Group on Brake NVH conducted a series of Round Robin tests and developed detailed recommendations for such measurements. The results of these tests are summarized in this paper. Initial results showed that there were difficulties with the identification of the types of modes being measured. However, when the results were carefully categorized, the measured natural frequencies agreed quite well. The measured damping coefficients showed much larger variations. In some instances, differences of more than 200% were found between testers. The steps taken to improve the consistency of results and subsequent Round Robin tests are described.

Accurate and robust knowledge of battery internal states and parameters is a prerequisite for the safe, efficient, and reliable operation of electric flying cars. Battery states such as state of charge (SOC), state of temperature (SOT), and state of power (SOP) are of particular interest for urban air mobility (UAM) applications. This article proposes a new safety-oriented multi-state estimation framework for collaboratively updating the SOC, SOT, and SOP of lithium-ion batteries under typical UAM mission profiles that explicitly incorporates the underlying interplay among these three states. Specifically, the SOC estimation is performed by combining an adaptive extended Kalman filter with a timely calibrated battery electrical model, and the key temperature information, including the volume-averaged temperature, highest temperature, and maximum temperature difference, is estimated using an adaptive Kalman filter based on a simplified 2-D spatially-resolved thermal model.

Panel cokers have been used for a number of years for the evaluation of lubricant formulations with respect to thermal oxidative stability. There are, however, a number of drawbacks to the technique, particularly related to variability of the test and correlations to real engine performance. As a consequence of this, work has been undertaken to develop a new thermal oxidative screen test which provides greater flexibility and better correlation to engine tests. The glass panel coker test has been developed from a combination of several screen tests, and consists of a heated sump, where the lubricant is aerated and has NO2 additions, and from which oil is circulated over a high temperature metal surface. The apparatus largely consists of standard laboratory glassware, and as such is easily customisable to incorporate additional features, for example simulated fuel or water dilution.

The concern of the public about environmental issues will ensure that the emissions from automotive engines continue to be the subject of scrutiny. A factor likely to be of increasing interest in the future is the degree of seal achieved at the exhaust manifold. The current trend for exhaust sealing is to use a sheet metal gasket with surface stress raising corrugations to form sealing regions. Such gaskets sometimes have strategically located coatings of filled elastomer or of exfoliated graphite. In all cases there are limitations with these styles of gaskets. There is now a new form of sealing material that is available that has a structure similar to that of the very familiar exfoliated graphite but which, unlike graphite, does not oxidise and is therefore very appropriate for automotive exhaust applications. The new material is based upon two forms of exfoliated vermiculite.

Modeling the tire forces and moments (F&M) generation, during combined slip maneuvers, which involves cornering and braking/driving at the same time, is essential for the predictive vehicle performance analysis. In this study, a new semi-empirical method is introduced to estimate the tire combined slip F&M characteristics based on flat belt testing machine measurement data. This model is intended to be used in the virtual tire design optimization process. Therefore, it should include high accuracy, ease of parameterization, and fast computational time. Regression is used to convert measured F&M into pure slip multi-dimensional interpolant functions modified by weighting functions. Accurate combined slip F&M predictions are created by modifying pure slip F&M with empirically determined shape functions. Transient effects are reproduced using standard relaxation length equations. The model calculates F&M at the center of the contact patch.

This paper describes a new system for early detection of tripped rollover crashes. The main goal of this system is to improve the protection of restraint devices, such as curtain window bags, in these rollover situations. This is achieved by a new rollover sensing (RoSe) algorithm in the airbag controller which produces a very early and robust deployment decision. Based on the analysis of tripped rollover test data, this paper shows how improved rollover sensing performance can be achieved by considering information about the vehicle's driving state before the rollover occurs. The results of this new approach are discussed in terms of deployment times. Finally a combined active and passive safety system architecture for the realization of the approach is suggested.

This paper describes a strapdown attitude/heading reference system (AHRS) designed to provide significant advancements in weight, volume, and cost. As such, it may be expected to replace conventional gyroscopic devices in transport category aircraft used in business aviation and government applications. In addition to unusual design objectives in the areas of weight, volume, and cost, the AHRS has met requirements for performance and reliability that equal or exceed that which would typically be experienced with the array of separate gyros and accelerometers which it can replace. These design achievements have been made possible by employing a new technology rate/acceleration sensor. The sensing principle is based on the fact that spinning piezoelectric elements measure coriolis accelerations which are proportional to applied rates. Additional piezoelectrical elements permit the sensing of linear accelerations as well.

Detecting the position of the crankshaft is one of the most essential tasks in modern combustion engines. The general demand for less fuel consumption and less exhaust emissions also yields in harsher requirements for crankshaft sensors regarding phase accuracy. Additionally, future sensors will have to operate under extreme environmental conditions as they will exist in modern engines with new components such as the integrated starter generator. One of the most promising approaches for rotational speed detection is the use of magnetoresistive sensors in front of a turning gear wheel. These sensors offer a high sensitivity to magnetic fields. Furthermore, the high signal-to-noise-ratio results in a very small phase error due to jitter. This makes the use of MR-technology very attractive for revolution counting with the parallel implementation of additional features, such as misfire detection, for example.

A new electronic sensor has been developed to measure the time-resolved concentration of carbonaceous particulate matter (PM) emitted in engine exhaust. One application of the sensor could be to provide cycle-resolved feedback on the carbonaceous PM concentration in the exhaust to the engine control unit (ECU), thereby enabling real-time control of engine operating parameters to lower PM emissions. Another promising application is to monitor the performance of particulate traps. The sensor was tested in exhaust flows from a single cylinder diesel engine and from a steady-state acetylene diffusion flame in a flow tunnel. Steady-state engine measurements were made at constant speed and variable load, and transient measurements were performed during engine start-up and accelerations. The sensor response was compared with an opacity meter and with gravimetric filter measurements.

The maintenance on condition is gaining more and more importance in the field of vehicle pool management. A crucial role in the vehicle maintenance is covered by the changing of the lubricating oil of the gearbox, the differential and the engine. In the lubricating oil different substances dissolve: metal traces from the mechanical parts as well as soot and fuel traces from the leakages unavoidably present in the moving parts of the engine. As well known, the oil loses its lubricating characteristics according to the content of the above contaminants. The aim of the present work is therefore to test a new sensors array whose function is to reveal the diesel fuel content in the lubricating oil. The array consists of different gas microsensors based on different metal oxide thin films deposited by sol-gel technique on silicon substrates.

This paper presents a new series of Timing and Injection Rate Control Systems: AD-TICS and P-TICS, for medium and heavy duty DI diesel engines. These TIC systems are equipped with a new concept of variable pumping rate, which is realized by controlling the prestrokes of the pumping elements. First, the outline of these new injection systems will be briefly described, showing the basic constructions and the range of applications, with some diagrams and schemata. Secondly, the injection characteristics of the jerk injection system will be clarified by simulation calculations, comparing the pump-pipe-nozzle with the unit injector. Calculation results will enable a comprehensive interpretation of the behavior of such injection characteristics as injection pressure, duration, etc., ie, in accordance with the pumping rate, dead volume, and nozzle orifice area, etc.. Furthermore, detailed characteristics obtained using AD-TICS and P-TICS will be shown.

A new fuel injection system has been developed to overcome the limitations of the existing mechanically operated jerk pump system. In the new system, a simple pump plunger is arranged next to the injection nozzle and is operated by a piston driven by fuel under pressure released from an accumulator. This arrangement permits control of injection conditions over wide ranges of engine speed and load. Two forms of the new system have been developed, one for large engines and one for small engines. Their construction, development, and performance are described. The requirements of fuel injection systems are defined, and the extent to which the old and the new systems meet them is considered. It is concluded that the new systems will improve overall engine performance and will prove even more valuable as load and speed ranges are extended.

The new type of fluid device described in this paper is closely analogous to a vacuum tube cathode follower amplifier. It provides an output pressure equal to an input control pressure, but with a high input impedance and low output impedance providing a power gain. A string of balls moving in response to pressures acting on the ball surfaces provides the basic valve action. Because of its structure and the use of balls as the control elements, this device is relatively easy to manufacture, does not require a lubricating fluid and can be operated at high temperatures.

The shock absorber plays a vital role in reducing the vertical and horizontal motions of the vehicle in order to have good handling and ride features. A good representation of the damper behaviour is very important in vehicle dynamics studies. The damper force of a shock absorber is indirectly generated by pressure-oil flow relationships through hydraulic valves, which are a part of the inner structure. A completely new aspect is the representation of damper force by mathematical expressions on the basis of a formula. A series of measurements have been carried out with aid of a hydraulic flow bench. The data obtained is fitted on the formula with coefficients, which describe some of the typical quantities of a shock absorber such as damping rate, blow-off factor and secondary damping rate with great accuracy.

Internal combustion engine modeling is nowadays a widely employed tool for modern engine development. Zero and mono dimensional models of the intake and exhaust systems, combined with multi-zone combustion models, proved to be reliable enough for the accurate evaluation of in-cylinder pressure, which in turn allow the estimation of the engine performance in terms of indicated mean effective pressure (IMEP). In order to evaluate the net engine output, both the torque dissipation due to friction and the energy drawn by accessories must be taken into consideration, hence a model for the friction mean effective pressure (FMEP) evaluation is needed.

The benefits of a well optimized carburetion, over the entire engine utilization range, are well known especially in conjunction with a catalytic aftertreatment of engine exhaust gas. Today, electronic injection systems appear very effective for the solution of the above mentioned problem, but their complexity, i.e. the number of components and the necessity of high current rates, and costs preclude their practical application on small engines. The proposed system, that maintains the simplicity of the standard carburetor and requires only small driving currents, for the simplified electronics, could represent a sound solution. In a first part, after a description of the system, flow bench tests are reported. In a second part the results of the practical applications on two different types of small motorcycle are presented. A detailed analysis of the parameters influencing the repeatability is also carried out.

Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation.

Improving the simulation support in engine development projects is a very attractive way to reduce cost and duration of such projects while increasing the deliverable quality. Thanks to advanced models and specific know-how, this paper presents a new step which consists in the use of simulation as a virtual engine bench for control design when the real engine is not yet available. In a first part, the goals and requirements of such a simulation approach are described. Then, the specific case of a two-stage turbocharger Diesel engine application from an IFP-RENAULT control design study is presented. At first, the virtual bench design is detailed from a methodological point of view. The engine simulator development and its use as a virtual control bench are then described. The control strategies design is presented, but also the anticipation of potential limitations such as inadequate turbocharger behavior or system failure detection management.

Alenia Aereonautica is manufacturing two fuselage sections of the new Boeing 787 airplane in a new plant in Grottaglie, Italy. The manufacturing line of the plant consists in 24 production cells and three Automatic Guided Vehicles (AGVs). The plant has been in production since the beginning of 2007. The shop floor information system controls both the cells and the AGVs using a Real Time software environment that allows three production shifts. The design of the most important cells is completely new and there are no statistics available to evaluate the Mean Time Between Failure (MTBF) and the effective productivity of the cell and of the entire moving line. Alenia Aereonautica made the request to study an adaptive Real Time Scheduler to control the yield of the plant and to allow the management to support the highly demanding yields from Boeing.

The development of the EP/VA … H fuel pump combines technical advantages of the injection pump principle and the versatility and reliability of in-line design. This paper describes the mechanical design and mode of operation of the single-plunger type injection pump. The governing principle of the EP/VA… H pump is a variable speed one, operative at will throughout the entire engine speed range. The distributor pump may be mounted in a vertical or horizontal position. The EP/VA… H is in production for 2-, 3-, 4-, and 6-cyl engines and accommodate maximum speeds of 5000 and 4000 rpm in the 4- and 6-cyl four-stroke cycle type engines.