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An integrated simulation tool has been developed, which is applicable to a wide range of design issues. A key feature introduced for the first time by this new tool is that it is truly a single code, with identical handling of engine, powertrain, vehicle, hydraulics, electrical, thermal and control elements. Further, it contains multiple levels of engine models, so that the user can select the appropriate level for the time scale of the problem (e.g. real-time operation). One possible example of such a combined simulation is the present study of engine block vibration in the mounts. The simulation involved a fully coupled model of performance, thermodynamics and combustion, with the dynamics of the cranktrain, engine block and the driveline. It demonstrated the effect of combustion irregularity on engine shaking in the mounts.

Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.

The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.

This paper describes the initial works related to the study of Internal Combustion Engines, as an object of mechanical design, at the Universidad Tecnológica de Pereira. It is reported a concise, complete methodology for simple model of internal combustion engine. The emphasis of the paper is placed on the use of the in-cylinder parameters (pressure and temperature) and inertial loads in the crank-slider mechanism to derive the loads that act on all the components of the crank-slider mechanism as well as the theoretical output torque for a given geometrical structure and inertial properties. These loads can then be used to estimate the preliminary dimensions of engine components in the initial stage of engine development. To obtain the pressure and temperature inside the cylinder, under different operation parameters, such as air fuel ratio and spark angle advance, a Zero dimensional model is applied. The heat transfer from the cylinder and friction are not taken into account.

Nisshin Steel Co., Ltd. has developed a new process for the production of a “one-side aluminized steel sheet”. The process utilizes a double layer one-side “stop-off” coating to prevent the molten Al from adhering to the steel surface. The “Stop-off” coating is removed by simple mechanical brushing after hot dipping. The characteristics of this product by above mentioned process are: 1) The steel side was as clean as a conventional cold rolled surface and showed no trace of the “stop-off” layer. Thereby, phosphating and ED painting were performed. 2) In the salt spray test data was obtained from zinc and Al coated steel surfaces; the coatings on both surfaces being of equal thickness.

Engineers doing squeak and rattle testing of instrument panels (IP's) have successfully used large electrodynamic vibration systems to identify sources of squeaks and rattles (S&R's). Their successes led to demands to test more IP's, i.e., to increase throughput of IP's to reflect the many design, material, and/or manufacturing process changes that occur, and to do so at any stage of the development, production, or QA process. What is needed is a radically different and portable way to find S&R's in a fraction of the time and at lower capital cost without compromising S&R detection results.

Engineers have long been restricted in designing and manufacturing one piece, hollow composite components with complex internal geometry. Complex core pulls in the plastic tool, major concessions made in the actual component design or components joined from several pieces were the early means of producing such components. Progressive thinking led to the use of matrix materials such as sand, salt and wax, which provided a measure of flexibility in allowing designed-in undercut areas. These materials, however, lacked the capability to meet the required demands of dimensional accuracy and internal surface, as well as proving themselves unsuitable for high volume production. The concerns for repetitive dimensional accuracy, quality internal surface and high volume production capability has now been satisfied with the use of low melting temperature metal alloys.

This paper presents an innovative brake booster which permits the brake assist function of the electric brake assist system to be implemented with mechanical means. The resultant significant reduction of manufacturing costs enhances the chances for a wide-spread use of this feature in all vehicle classes, thereby making an important contribution to the general improvement of traffic safety. Based on an analysis of the mechanically detectable physical variables for recognizing a panic situation and an evaluation of possible methods of mechanical valve activation, the paper presents a mass production solution and describes its functional properties. In particular, it should be noted that the possibility of controlling the braking pressure within the brake assist function even represents a functional advantage

The influence of engine variables on the concentration of oxides of nitrogen present in the exhaust of a multicylinder engine was studied. The concentrations of nitric oxide (NO) were measured with either a mass spectrometer or a non-dispersive infrared analyzer. The NO concentration was low for rich operation (deficient in oxygen) and increased with air-fuel ratio to a peak value at ratios slightly leaner than stoichiometric proportions. A further increase in air-fuel ratio resulted in reduced NO concentrations. Advanced spark timing, decreased manifold vacuum, increased coolant temperature and combustion chamber deposit buildup were also found to increase exhaust NO concentration. These results support either directly or indirectly the hypothesis that exhaust NO concentration is primarily a result of the peak combustion gas temperature and the available oxygen.

To prevent engine scuffing in the field a new laboratory test called the Hot Tube Test has been established in order to evaluate the high temperature stability of diesel engine oils. In a strip mining application field test using 47 bulldozers powered by the same engine type, half of the engines suffered from piston scuffing failures when operated on a variety of commercially available API CD quality SAE 30 Grade engine oils. All the field test oils have been investigated using the Hot Tube Test, and an analysis of the results indicates that it would be possible to accurately predict scuffing failures by this test method. Furthermore, the reliability of this analysis has been verified by bench engine testing on reference oils. The reasons why the Hot Tube Test predicts the anti-scuffing performance of engine oils are discussed.

Over the last ten years there has been a steady growth in the market share of light-duty diesel engines, especially in Europe. At the same time, a general trend in petrol engine development has been seen, in which normal aspirated engines are being replaced by downsized turbocharged engines. Therefore, NVH engineers have to deal with new challenges. Turbochargers produce an aerodynamic noise in the frequency range above 1000Hz, which might influence the exterior and interior noise level. As a result, the additional requirement for acoustical components to reduce this flow noise is going to pose an increasing challenge for air intake system suppliers. This paper describes a new design of well-known wide band silencer first mentioned by A. Selamet, N.S.Dickey and J.M.Novak [1,2]. The silencer works according to the interference principle. The sound is guided into two or more parallel pipes of different lengths.

Geometric dimensioning and tolerancing is both a “language” and a “technique.” Its objective is to facilitate design, production, and inspection and, simultaneously, provide the most economic results. This paper describes the implementation and practice to accomplish these through illustrating methods to state design requirements specifically and clearly and to provide for maximum producibility, uniformity of interpretation, etc. The need to reflect a common objective for design, production, and inspection via the stated drawing requirement is emphasized. Application and interpretation of geometric characteristics (emphasizing symbology), fundamentals, rules, etc. are presented. Basis for the content of this paper is USASI Y14.5-1966 “Dimensioning and Tolerancing for Engineering Drawings.”

Driver state monitoring is a crucial technology for enhancing road safety and preventing human error-caused accidents in the era of autonomous vehicles. This paper presents CogniSafe, a comprehensive driver monitoring system that uses deep learning and computer vision methods to detect various types of driver distractions and fatigue. CogniSafe consists of four modules: Driver anomaly detection and classification: A novel two-phase network that proposes and recognizes driver anomalies, such as texting, drinking, and adjusting radios, using multimodal and multiview input. Gaze estimation: A video-based neural network that jointly learns head pose and gaze dynamics, achieving robust and efficient gaze estimation across different head poses. Eye state analysis: A multi-tasking CNN that encodes features from both eye and mouth regions, predicting the percentage of eye closure (PERCLOS) and the frequency of mouth opening (FOM).

This paper, confined to the application of hard chrome plated liners to high-speed four-stroke diesel and gasoline engines, illustrates the increase in their popularity in the United Kingdom, and the advanced production methods which make this economically possible. The need for balanced engine life has long been apparent and is even more important today, the growth of motor transport having outstripped repair facilities. Iron bore life has been surpassed by improvement in the life of other component parts in the modern diesel engine. The provision of hard chrome plated liners can restore the balance. Further development and turbocharging of diesel engines has shown the need for a bore material capable of preventing scuffing and galling at elevated temperatures. Hard chrome has already proved itself in four-stroke engines under these conditions.