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This paper proposes a platform to conduct rapid development, simulation and test of autonomous driving vehicles. By combining the advantages of rapid prototyping and software development, the proposed platform could automatically generate codes and download them into domain controllers, therefore the efficiency of development process of the core functions of ADAS can be largely improved. The platform is made up of scene simulation, vehicle dynamics simulation software, a rapid prototyping system, a chassis drive-by-wire control and road-load simulation system. Meaningful tasks including key algorithm development, MIL simulations, domain controller based HIL tests and the development of drive-by-wire systems can all be accomplished by the platform.

The testing division of the European Space research and Technology Center (ESTEC) upgraded its TEMPerature Data Acquisition System (TEMPDAS) of the Large Space Simulator (LSS) by adding a PlaTinum resistor Data Collection Unit (PTDCU). The unit is integrated in the rotating part of the LSS motion simulator. It is therefore operating at extreme temperatures and under vacuum, as it is for flight equipment.

Decibels were originally developed in the 1920s by the telephone industry (AT&T and Bell Labs). Initially the unit was the bel, derived from the name of Bell Labs and defined as the logarithm to the base 10 of the transmission loss of electrical power in telephone lines. It was also used for voice signals in telephones where the preferred unit became a tenth of a bel or decibel. The adoption of decibel for sound appears to be due principally to the dominant position of the Bell's acoustical research staff in the 1920s and 1930s. Octaves have their origin in music and were used to facilitate the use of analogue filters in partitioning the frequency scale. Partitioning into octaves divides the frequency scale into bands increasing in width by a factor of 2 with increasing frequency. To obtain greater resolution, the partitioning is often performed in 1/3 and sometimes in 1/12 octaves. However resolution remains poor particularly at higher frequencies.

This study intends that the new designers are trained about the experiences and expertise rapidly and the possible faults are eliminated by using intelligence knowledge - based system. For this reason, the studies of design students and young designers in industry were analyzed, the mistakes were determined according to the fundamental rules of machine design and a data base was prepared for intelligence knowledge - based system. After, the system was made interactive with CAD software which was used in our design studies. So, an intelligence system that can warn for mistake in design stage and can list fault testing its self after design was created. Finally, it is expected that this intelligence system will shorten the experience time of young designers and will prevent fault in design stage when this comprehensive study completed.

The electrification of vehicle fleets for urban delivery transport is becoming increasingly important due to ever stricter legal requirements and the high public pressure on companies. In this paper, a converted 3.5 t light-duty vehicle with a maximum gross weight of 7.5 t is presented. The vehicle has a serial hybrid electric powertrain with a maximum electric traction power of 150 kW and a 60 kW fuel cell range extender, and uses a 46 kWh battery with 400 V mean voltage level, resulting in a full electric range of 120 km. The electric drive is realized with an induction motor and a lithium-manganese-iron-phosphate (LMFP)-battery as well as a 2-speed gearbox. The fuel cell system has a fuel tank with 100 l volume and 700 bar pressure level, resulting in a total mass of around 4.2 kg of hydrogen. This enables an overall vehicle range of 400 km.

This paper examines an originally designed airbag deployment system for use in static experimental testing. It consists of a pressure vessel and valve arrangement with pneumatic and electric controls. A piston functions like a valve when operated and is activated pneumatically to release the air in the tank. Once released, the air fills the attached airbag. The leading edge velocity can be controlled by the initial pressure in the tank, which can range up to 960 kPa. Three different test configurations were studied, which resulted in leading edge deployment speeds of approximately 20 m/s, 40 m/s, and 60 m/s. In experiments using this system, seven types of airbags were tested that differed in their material, coating, and presence of a tether. Data for each series of tests is provided. High speed video and film were used to record the deployments, and a pressure transducer measured the airbag's internal pressure.

Braking energy recovery can significantly contribute to fuel economy and emission reduction, particularly for commercial vehicles driving in urban environment. By using the compressed air storage, rather than expensive and vulnerable batteries, this paper proposes a pneumatic hybrid system with an integrated compressor/expander unit (CEU) for commercial vehicles, in order to achieve stop/start function and braking energy recovery. During braking, the compressed air is recovered by CEU working in compressor mode and is charged to the air tanks. When the vehicle starts from stop, the CEU works as an expander to crank the engine with compressed air. The compressed air can also be used to supply the air tank of brake boost system, thus reducing its energy consumption. The mathematical models of energy conversion units, including the two modes of CEU and the air brake system, are established and analyzed.

The U.S. general aviation manufacturing industry has deteriorated almost to the point of extinction within the past decade. There are several factors potentially contributing to this deterioration; however, the escalation and unpredictability of product-liability costs are claimed to be the most significant. General aviation manufacturers are subject to the product-liability laws of each state. Efforts to reform this system have been underway since 1986. However, these efforts have been stymied by opponents whose primary concern is that the reform will not allow some accident victims to be properly compensated for their damages. There are immediate policy alternatives that will potentially alleviate the product-liability problem of the industry: General Aviation Accident Liability Standards Act, Product Liability Fairness Act, and state reform. Other alternatives that require further investigation include increased safety regulation and mandatory pilot liability insurance.

As there are a variety of uncertainty contained in dynamic systems, this paper presents a method to identify the uncertain parameters of Load Sensing Proportional Valve in a heavy truck brake system. This method is derived from polynomial chaos theory and uses the maximum likelihood approach to estimate the most likely value of uncertain parameters, such as equivalent bearing area diameter of the diaphragm, preload of return spring and so on. The maximum likelihood estimates are obtained through minimizing the cost function derived from the prior probability for the measurement noise. Direct stochastic collocation has been shown to be more efficient than Galerkin approach in the simulation of systems with large number of uncertain parameters. The simulation model of Load Sensing Proportional Valve is built in software AMESim based on logic structure of the valve. The uncertain parameters are estimated through the simulation results which are treated as measurements.

In this paper, a new computational method is provided to identify the uncertain parameters of Load Sensing Proportional Valve (LSPV) in a heavy truck brake system by using the polynomial chaos theory. The simulation model of LSPV is built in the software AMESim depending on structure of the valve, and the estimation process is implemented relying on the experimental measurements by pneumatic bench test. With the polynomial chaos expansion carried out by collocation method, the output observation function of the nonlinear pneumatic model can be transformed into a linear and time-invariant form, and the general recursive functions based on Newton method can therefore be reformulated to fit for the computer programming and calculation. To improve the estimation accuracy, the Newton method is modified with reference to Simulated Annealing algorithm by introducing the Metropolis Principle to control the fluctuation during the estimation process and escape from the local minima.

The sophistication factor “S” is a number expressing deviations from isentropic operation of a gas turbine flow path due to gas dynamic effects. It may be used with remarkable accuracy in polytropic equations to analyze gas turbine cycle performance. When related to statistics, it provides a means of evaluating proposed or existing engines with respect to current technology status. A corresponding technique for dealing with recuperators is also presented.

A population study of restrained child occupants under the age of 14 who were killed in car accidents has been conducted over the past 13 years. The restraint systems included rearward facing infant carriers, child seats, child harnesses and adult belts with or without booster cushions. The cases are discussed according to restraint type and crash configuration. Problems of misuse or malfunction are described. Guidelines for improved restraint design are presented.

This work examines the characteristics of a methanol fueled porous media burner, the principles of which may be used as a basis for a practical radiant heat source for an on-board catalytic methanol reformer. The burner uses a conventional engine port fuel injector designed for methanol use. The spray from the injector was impinged upon the bottom of a stack of two or three pieces of ceramic foam. The ceramics were 2.5 cm thick, 10 cm in diameter and were enclosed in a quartz cylinder for visualization. The upstream ceramic acted as a flame holder and the surface of the downstream ceramic was the radiation source. The range of air and fuel flow rates over which stable combustion was possible was investigated. Fuel flow rates between 0.12 and 0.48 gm/s were examined. Overall equivalence ratios between 0.65 and 0.2 resulted in stable combustion.

Temperature and humidity control using condensing heat exchangers in microgravity requires condensation and separation of liquid from the air stream. A layered porous media-based condensing heat exchanger where capillary suction is used to imbibe and selectively remove the condensed water from a flowing air stream provides an attractive alternative to current designs. Experiments using a porous flat-plate, consisting of top and bottom halves with cooling tubes embedded in the middle, show that a hydrophilic porous graphite substrate can condense, and imbibe moisture without forming a liquid layer on both the top and bottom parts of the condensing surface. Measured condensation and heat transfer rates for a porous graphite substrate for a range of inlet air temperature and relative humidity at atmospheric pressure are presented in this paper.

A new microcomputer-based statistical measurement system can accurately acquire vehicular ignition generated RFI impulse noise data and quickly reduce it to tabular and plotted outputs of the distributions of amplitudes and of periods between occurrences of a particular amplitude. This user-interactive system obtains distributions generated by all cylinders or, by synchronous electronic gating using a fractional-cylinder window, obtains distributions generated by any portion of any isolated cylinder. It permits quick and effective testing of proposed designs and design changes during the development process. This paper presents system description, system proveout and system application results.

Transport Vehicle Operations Managers can obtain certain benefits from knowledge of the vehicles use and driver actions. A digital electronic recorder samples and retains data on specific vehicle operating conditions. The use recorder can be driver or vehicle assigned for the appropriate monitoring function. A data processing system provides on-site, immediate reports of relevant measurements and subsequent reports analyzing multiple-vehicle and multiple-driver performance.

The method for measuring air-fuel ratio is generally based on analysis of the exhaust gas components and its calculations. A new instrument has been developed which uses this method, but it attaches an oxygen sensor for exhaust gas analysis to the exhaust pipe and calculates the air-fuel ratio directly from the sensor output using a microprocessor. The response time of this instrument is 100 milliseconds and because it does not require an exhaust gas sampling system its weight is only 2.5 kg. This paper describes the operation theory, construction and characteristics of this instrument, as well as the results of air-fuel ratio of measurements on engines and vehicles using this instrument in a transient state.

Track shoes made of Metal Matrix Composite (MMC) are light in weight, and can resist high temperature and wear. Defects such as disbond, cracks and porosity can be introduced during the manufacturing process and while in service. Presented in this paper is a portable nondestructive inspection (NDI) system to automatically inspect the tank track shoes for disbond, cracks and porosity defects. The work focuses on the inspection of the track shoe center spline where MMC inserts are attached to the aluminum substrate. A hybrid approach has been developed where an array of broadband high frequency ultrasonic transducers operating in a pulse/echo mode are utilized to detect disbond, and a scanning eddy current probe array is used to detect cracks and porosity. The Inspection results agree quite well with immersion ultrasonic C-scan images and destructive tests.

A need was identified by those involved in the seating development process for an improved method of collecting anthropometric data on individuals. This paper documents the objectives, resulting hardware and experimental procedures of an anthropometer developed utilizing a new technology. The anthropometer described is more portable and collects data faster and more easily than previously available tools, with greater accuracy and confidence † in the results.

The design, construction, and typical application of a portable, passive element network analyzer is described. This device was designed for use in the simulation, analysis and design of complex aerospace systems. When programmed, this analyzer becomes an electrical model of a physical system rather than a computer for the solution of mathematical models which represent a physical system. The advantages of this design are its small size, economy, and availability of all programming elements on a single compact unit. An example problem is also described to illustrate the typical application of the network analyzer in the solution of engineering problems.