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The use of mechanical, electrical, electronic, computer, and control engineering concepts combined in a particular machine or process is occurring at an increasingly rapid pace. The integration of these concepts is referred to as mechatronics. Engineers and technicians now must have knowledge and skills in all of the areas mentioned. Mobile machines have always incorporated knowledge from a variety of areas as needed to incorporate desired features and work functions. However, the time has come to make a more formal recognition of this integration of ideas.

One way to improve diesel engine performance and to reduce emissions is improving power density and combustion cycle efficiency. It can be done by increasing combustion pressure and engine speed drastically and also by improving the controllability of the engine. Besides of the fuel injection system the key element in improving controllability is the valvetrain. Extreme combustion pressure and engine speed set special requirements for valvetrain design. As the pressure and engine speed are increased the load on the valve actuation mechanism becomes higher because of the higher pressure acting on the valve plate and also the need for higher acceleration. High instantaneous power required due to high load makes electrohydraulic system a natural choice for actuation mechanism. An electrohydraulic camless valvetrain (IHAflex) for extreme value engine (EVE), developed by Institute of Hydraulics and Automation of Tampere University of Technology, uses neither cams, nor retainer springs.

This article reports on the effects of various types of high field electrical phenomena imposed on low load lean combustion in a spark ignition petrol engine. The first part of the work deals with purely electrical field effects with no induced ionization. An electric field was applied via an insulated static high voltage DC electrode (up to 15 kv) which does induce excess charge effects, near the spark source. This was found to have very modest effects on the imep and its cyclic variability, which are unlikely to be significant enough to warrant commercial development. Further work reported here concerns the testing of an electrohydrodynamic device formed from a modified spark plug. This was operated in a test chamber under typical pre-combustion pressures where it was possible to obtain corona flows up to 10 m/s.

The Electroimpact Automatic Fan Cowl Riveter exhibits new and unique design features and automated process capabilities that address and overcome three primary technical challenges. The first challenge is satisfying the customer-driven requirement to access the entire fastening area of the fan cowl doors. This necessitates a unique machine design which is capable of fitting ‘inside’ a fan cowl door radius. The second challenge is determining drill geometry and drill process parameters which can produce consistent and high-quality countersunk holes in varying mixed-metal stack-up combinations consisting of aluminum, titanium, and stainless steel. The third challenge is providing the capability of fully automatic wet installation of hollow-ended titanium rivets.

Characteristics of electroless nickel plating which have provided advantageous application in aircraft maintenance operations have included high throwing power resulting in uniform coverage of partially blind areas, close dimensional tolerance control, high hardness controllable by heat treatment to provide good wear resistance and good corrosion protection. More recently, it has been shown that modern high phosphorous coatings provide improved adherence and strength which severely limited application of earlier electroless nickel coatings. The process has now been approved by an engine manufacturer for optional replacement of electrolytic nickel plating for diffused nickel-cadmium coatings on selected parts. It is the purpose of this paper to review some of the current applications and consider potential new uses for this process.

A metallic matrix composite coating has been developed that imparts unique surface properties to a wide range of metallic substrates. The coating, based upon conventional electroless nickel technology, incorporates sub-micron particles of PTFE distributed uniformly throughout the coating thickness. The presence of the PTFE provides a continuous reservoir of lubricating particles giving a low friction surface that is accurate over the most complex components and that has many potential aerospace applications.

From failure to success in developing a direct sunlight readable electroluminescent display for use in general aviation cockpits. Initial attempts using existing technologies resulted in failure of a product design. Using new EL driver design approaches a 76.2 mm x 127 mm EL display with an unfiltered average brightness of 65 foot lamberts (1) was developed which proved to be satisfactory across the range of dark night to bright day sunlight ambient lighting conditions within an aircraft cockpit. A circular polarized contrast enhancement filter was developed for the EL display. Although the filter lowered the average brightness to 24 foot lamberts the overall readability was increased. EL displays may be a good alternative to other technologies for use in direct sunlight applications.

A pilot plant facility has now been established to build DC electrolumescent panels. A new product is being made which combines analogue and digital readouts on one panel. Any panel up to 6″ × 18″ can be made due to the process simplicity which consists largely of screen printing techniques. The pilot product is 2″ × 7″ and displays are made six at a time. A combination of custom designed I.C.'s and microprocessor drive can be used to provide full, flexible solid state instrumentation.

Lithium-ion rechargeable batteries have been demonstrated to have high energy density, high voltage, and excellent cycle life which make this technology more attractive than competing systems such as Ni-Cd and Ni-H2. However, the SOA cells fail to meet certain requirements necessary for various future NASA missions, such as good low temperature performance. Under a program sponsored by the Mars Exploration Program we have developed an organic non-aqueous electrolyte which has been demonstrated to result in improved low temperature performance of lithium-ion cells. The electrolyte formulation which has resulted in excellent low temperature performance, as well as good cycle life performance at both ambient and low temperatures, consists of a 1.0M solution of a lithium salt, lithium hexafluoro-phosphate (LiPF6), dissolved in a mixture of carbonates: ethylene carbonate + dimethyl carbonate + diethyl carbonate (1:1:1).

The electrolytic liquid display is a new passive particularly designed for automotive applications. It looks like liquid crystal display but operates on a completely different way by electrolysis phenomenous. A small current at low voltage produces the transfer of silver from a back glass where silver is not visible to the front glass where the thin layer of silver obtained gives a black surface. This type of display fulfil almost all the requirements of automotive uses such as temperature operating range, viewing angle, shocks and vibrations. Their manufacture operations are cheaper than those for liquid crystal and must finally give a lower manufacturing cost. At last one particularity is its memory effect which may be in some cases an advantage.

Electrolytic machining is advantageous to use when the material is very hard or tough, when the amount of material to be removed is large, or when the number of pieces to be machined is great. Its greatest future however lies in the new freedom it gives to designers, by enabling them to design parts with shapes and contours for the most efficient service.

Phosphating is a surface treatment process widely used for preparing metal surfaces before painting. The phosphate coating plays a very important role in enhancing after-painting corrosion resistance, which is one of the essential quality requirements of painted surfaces. Continued research and development is therefore under way in various parts of the world to increase the corrosion resistance enhancement effect of phosphating. Moreover, because the demand for environmental protection has been increasing in recent years, reducing the amount of waste (sludge) generated during the phosphating process is also strongly required. To meet these requirements, we have developed a novel phosphating technology called the “electrolytic phosphating process,” which drastically enhances corrosion resistance after painting and reduces sludge generation. The developed process has already been put to practical use for surface preparation before cation electrodeposition painting of automotive parts.

The paper reports on the introduction of a tricationic prephosphating process for electrolytically galvanized steel strip (EZ sheet). The properties achieved by way of prephosphating are described. The aspects of corrosion protection, paint adhesion and formability are discussed, as well as questions concerning development and application, the practical worth of prephosphating from the point of view of the auto industry.

Among the many advantages of the hybrid variants of Automated Mechanical Transmissions (AMTs) such as the Dual Clutch Transmission are faster gearshifts and excellent acceleration that comes from reduced drive-train losses without torque interrupts which translates into improved drive quality through smoother shifts. However, actuator system dynamics and controls remain critical challenges to attaining the full benefits of such AMT variants, which demands precise timing and coordination of the actuators. This paper presents a method for modeling a solenoid, including its non-linear electromagnetic characteristics. The model has been validated against experimental measurements. The significance of the work is that an efficient and robust method that allows precise predictions of a hydraulic valve pressure, flow through the system and the position of the hydraulic elements has been devised.

Permanent magnet brushed DC (PMBDC) motors are mostly preferred in many automotive applications because of better power density and easier control. Five different automotive applications such as electric parking brake (EPB), power seat, power window, sunroof drive, and tire air pump are chosen and discussed in this paper. A step-by-step electromagnetic analysis is carried out for all the designed models. Low-cost ferrite-based magnets are used for cost reduction keeping the efficiency as high above 77% in all the models. Comparison on performance and cost are discussed in the conclusion section.

This paper describes the modelling and electromagnetic analysis of Permanent Magnet Brushed Direct Current (PMBDC) motor using Finite Element Analysis (FEA) software packages. The designed motors referred in this analysis are fit for use in applications of the electronic throttle control and exhaust gas recirculation in automobiles. Performances of the designed PMBDC models are compared with the traditionally used machines. Three PMBDC models with different operating characteristics are proposed for the two applications. Each model is suitable for use in both applications. Cost analysis of the motors is also carried out, and comparison with the traditionally used machines is done.

Interference bolts are widely used in aircraft assembly. Electroimpact has used its Low voltage Electromagnetic Riveter (LVER) technology to automatically swage collars on these bolts. The bolts are installed using two process tools, a percussive bolt inserter and the EMR. The bolt inserter inserts the bolt and the EMR swages the collar. This increased productivity over manual installation, but there was still production time to be saved. The Electromagnetic Bolt Inserter (EMB) was designed to increase production rate even more when installing bolts and swaging a collar onto the bolt. The EMB combines the great benefits of Electroimpact's Low Voltage Electromagnetic riveting technology with a bolt inserter.

The Electromagnetic Bolt Inserter (EMB) is a new tool that combines functions that on previous machines were performed by two tools, a bolt inserter followed by an EMR. By combining the operations of two tools in one the processing time for the wing spar is reduced. The tool incorporates quality checks for bolt length, stake height and bolt insert height.

This paper describes the comparison of electromagnetic characteristics of two different superconducting-motor structures for electrified aircraft propulsion systems. Future electrified aircraft demand higher output (over 16 kW/kg) and higher efficiency (> 98%) for their motors in comparison with current ones. To satisfy the demands, two kinds of superconducting motors are dealt in this study: one is partially superconducting motors (PSCMs), made of superconducting field coils and copper armature windings; the other is the fully superconducting motors (FSCMs) made of superconducting field/armature windings. They are cooled at 20 K with liquid hydrogen. We designed these two motors with finite element method to obtain the output density of 16-20 kW/kg for future electrified propulsion systems. We selected 3.0- and 5.0 MW superconducting motors, considering the application to aircraft for almost 180 passengers and 44 MW rated power for take-off.

This paper emphasizes the need for all people concerned in the design and operation of electronic military devices to recognize and take into account the existence of problems in electromagnetic compatibility. The Electromagnetic Compatibility Program of the Dept. of Defense is described, and numerous interdependent aspects of the program that require careful management attention are touched upon.