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Magnetic induction heating can be used to bond automotive seat trim covers to foam pads. A thermoplastic film doped with ferromagnetic particles is placed between the trim cover and foam pad. An induction coil can be designed for specific seat contours in a tool press. When current is applied to the induction coil located in the tool, magnetic flux is induced. Eddy currents generated in the ferromagnetic particles activate the hot melt film. Heat is delivered directly to the bondline. The process does not damage heat sensitive trim materials (i.e.. leather, vinyl) as the tool surface remains cool. Process reversibility permits design for recyclability and a reduction in production scrap rates.

There are two well known basic concepts for achieving magnetic levitation of vehicles: one is based on electromagnetic attraction (EMA); and the second method is based on electrodynamic repulsion (EDR). In turn, each of these concepts have at least two variations (1, 2, 3, 4 and 5)1 This paper presents a description of a lesser known third form of magnetic levitation which in the USSR is called the dc circuit Magnetic Potential Well (MPW) effect, developed by Kozoriz (6); and known in the West as Laithwaite's Magnetic River (13) which, however, is illustrated for an ac circuit. Furthermore, it identifies the boundary conditions which are needed to achieve the dc circuit MPW effect, and illustrates the final forms of the mathematical relationships derived to reduce the MPW concept to practice, in the design of practical high speed Maglev vehicles, for automotive and/or mass transit applications.

There are two well known basic concepts for achieving magnetic levitation of vehicles: one is based on electromagnetic attraction (EMA); and the second method is based on electrodynamic repulsion (EDR). In turn, each of these concepts has at least two variations (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 and 19)1 This paper presents a third form of levitation known in the Ukraine as the Magnetic Potential Well (MPW) developed by Kozoriz (20, 21, 22 and 23), and in the West as Laithwaite's Magnetic River (24)(25). The MPW concept, in effect, electrifies the passive sidewall levitation coils of the RTRI EDR (16) system to obtain levitation at zero vehicle velocity and during acceleration to cruising speed. This dc electrification of sidewall levitation coils eliminates the need for wheels during acceleration from standstill and deceleration in the station. Specifically, MPW levitation force exhibits a stable positive slope as the levitation gap increases.

This is a comparative assessment of the three magnetic levitation high speed mass transportation systems currently under extensive development, and in the prototype vehicle demonstration stage, in the Federal Republic of Germany (FRG) and in Japan: One approach, which is promoted by Transrapid International (TRI) in FRG, is based on the electro magnetic levitation (EML) concept; a second approach, which is promoted by the High Speed Surface Transport Corporation (HSST), is based on the EML concept developed and licensed from Japan Air Lines (JAL); a third approach, which is promoted by the Railroad technology Research Institute (RTRI) (Sogo Tetsudo Gijutsu Kenkyusho), the developer of the Shinkansen train, is based on the super conductive electro dynamic levitation (EDL) concept.

A commercially available magnetic reluctance sensor is used to determine the angular velocity of turbocharger impeller blades from outside the aluminum housing. Eddy currents are induced in the aluminum blades by blade motion through the magnetic field projected by an externally mounted Samarium-Cobalt permanent magnet. Test results show that a circuit designed to track the blade signal gives an analog voltage output proportional to the frequency of blade passage over the operating range of the Cummins VT-903 and Detroit 8V-71T turbocharged diesel engines. Cam shaft rotational frequency is measured on Cummins and Detroit deisel engines by sensing the motion of ferromagnetic rocker arm parts through a conducting and possibly ferromagnetic valve cover shield. A strong rare earth Samarium-Cobalt magnet and a wire sensing coil are placed outside the valve cover above the rocker arm.

All commonly used speed sensitive power steering assist systems for cars are based on hydraulics. These systems change the pressure or modulate the flow of the conventional hydraulic power steering system. They require some means of actuation in the form of an electromagnetic device such as a solenoid actuator working as a flow or pressure regulator or brushless motor driving a hydraulic pump. Usually they are pulse width modulated controlled by a microprocessor. Therefore, these systems can be quite complicated. This paper describes MAGNASTEER, a novel magnetic speed sensitive system developed at Saginaw Division in cooperation with the NAO Research and Development Center, which is an add on to the basic hydraulic power steering system. The effort variation provided by MAGNASTEER is the result of an electronically controlled electromagnetic torque, which acts as an addition or subtraction to the torsion bar torsional rate, effectively varying the feel of the hydraulic system.

All commonly used speed sensitive power steering assist systems for cars are based on hydraulics. These systems [ILLEGIBLE]ange the pressure or modulate the flow of the conventional [ILLEGIBLE]draulic power steering system. They require some means of [ILLEGIBLE]ctuation in the form of an electromagnetic device such as a solenoid actuator working as a flow pressure regulator or brushless motor driving a hydraulic pump. Usually they are pulse width modulated controlled by a microprocessor. Therefore, these systems can be quite complicated. This paper describes MAGNASTEER a novel magnetic speed sensitive system developed at General Motors Corporation. The effort variation provided by MAGNASTEER is the result of an electronically controlled electromagnetic torque, which acts as an addition or subtraction to the torsion bar torsional rate, effectively varying the feel of the hydraulic system.

For tubular terminals and high power junctions, the magnetic pulse crimping (MPC) could be a technical solution to produce aluminum - copper assembly. LEONI has launched a study to evaluate this technology. Besides, the lifetime of vehicle components is an issue that manufacturers should consider during all the development phases from the conception to the validation in service. Consequently, the quality of the interface aluminum-copper obtained by MPC is evaluated in terms of microstructure, of electrical and mechanical properties and to describe the corrosion behavior.

Magnetic Pulse Welding (MPW), a cold solid state bonding process, is becoming a viable replacement for conventional fusion welding processes and explosive welding for tube to tube applications. The process is presented in this paper together with its fundamental equations. Some examples of similar & dissimilar weld applications are illustrated as well as some interface microstructures.

Cryogenic systems will be a part of the Space Station and future space platforms in a variety of applications, such as propellant management and cooling of scientific instruments. The projected Space Station initial usage of cryogenic propellants is relatively small so the primary refrigeration need is for cooling scientific instruments and various sensors. A potential method for meeting these cooling requirements is the use of a refrigerator based on the temperature changes in certain magnetic materials upon application or removal of a magnetic field; i.e. the magnetocaloric effect. This type of refrigerator, known as a magnetic refrigerator, offers potentially higher reliability and lower power requirements than conventional refrigeration units. Also, the higher power density of the magnetic refrigerator is an attractive feature for space station and space platform applications.

Many synchronous electric motors require a very accurate position sensor compatible with a sinusoidal control. The purpose of such a control is to enable an efficient and smooth operation enhancing the comfort by limiting vibrations. In some cases related to mechanical constraints, we have to deal with through-shaft design. One can quote for examples power drives for Electric or Hybrid Electric Vehicles as well as for Electric Power Steering motor. More generally, these sensors need to keep a simple and robust design and a restricted number of parts as they are submitted to high vibration levels, a wide temperature range and speeds of several krpm. In order to meet such requirements, MMT has developed a magnetic sensor principle offering a competitive alternative to the conventional inductive resolver type sensors. The basics of this solution is a through shaft angular position sensor using one or two Hall-effect probes.

Magnetic resonance imaging (MRI) has been used to investigate gas flow in diesel and gasoline particulate filters, exploring gas flow both within the channels and also at the entrance and exit of the filters (expansion and contraction effects). The latter measurement can be used to measure turbulent diffusivity in the filter bulk flow characteristics, and therefore estimate the importance of entrance and exit effects in contributing to overall filter back pressure as the filter properties and/or exhaust flow changes (i.e. with Reynolds number). The former measurement gives information that can be used to evaluate filter performance, in particular with respect to filtration efficiency, and examples will be shown from our measurements on diesel filter systems.

There is an ever-present risk for the lower ram on a riveting machine to suffer a damaging collision with aircraft parts during automated fastening processes. The risk intensifies when part frame geometry is complex and fastener locations are close to part features. The lower anvil must be led through an obstructive environment, and there is need for crash protection during side-to-side and lowering motion. An additional requirement is stripping bolt collars using the downward motion of the lower ram, which can require as much as 2500 pounds of pulling force. The retention force on the lower anvil would therefore need to be in excess of 2500 pounds. To accomplish this a CNC controlled electromagnetic interface was developed, capable of pulling with 0-3400 pounds. This electromagnetic safety base releases when impact occurs from the sides or during downward motion (5 sided crash protection), and it retains all riveting and bolting functionality.

This paper discusses the possible impact of the FM tape recorder and servo-hydraulic actuators on the testing of automotive structures. The use of tape recorders and automatic data reduction systems will permit more accurate definition of service conditions and properly “set-the-stage” for laboratory testing. Servo-hydraulic strokers should encourage better laboratory simulation because of their great flexibility. Test set-up time is reduced, fixtures can be simplified and load control is more precise. Simultaneous multiple inputs can be controlled as to amplitude and phase relationships.

The torque sensing module is an important part of EPS (Electronic Power Steering) system. There are various solutions in the market based on different technologies i.e. Potential meter, Inductive and Hall sensing. As a trend, more and more EPS system integrators adopt Hall-based torque sensing solution, most of which consist of a magnetic ring, a magnetic flux detector to read the magnetic flux from the magnetic ring and a flux conductor/concentrator to lead the magnetic signal to a Hall device to convert magnetic flux level to electronic signal. However, available solutions require high mechanical precision from the magnetic flux detector and conductor/concentrator. Also, the magnetic ring in the existing solution is magnetized after its preformation which causes a lower signal-to-noise ratio at the input of the entire system due to the process and brings about less accuracy of the torque sensing module.

Experimental results on an automatic lane keeping control study are presented in this paper. A magnetic reference system was used to provide the vehicle lateral tracking error as well as future road curvature information and vehicle speed measurement to the vehicle steering controller. The front wheels of the vehicle are steered according to vehicle lateral displacement, future road curvature, vehicle yaw rate and lateral acceleration, and vehicle speed. The control algorithm used to design the feedback and feedforward controllers is known as the Frequency-Shaped-Linear-Quadratic Preview (FSLQ-preview) optimal control design method. The closed loop response of the vehicle was examined under a wide variety of test conditions, including low tire pressure, measurement noise, perturbed reference system, hard braking, and snowy road.

Solid wastes can be separated from aqueous streams and concentrated by filtration in a magnetically assisted fluidized bed. In this work the filtration of solid waste materials using filter beds consisting of granular ferromagnetic media is demonstrated. The degree of bed consolidation (or conversely fluidization) is controlled by the application of magnetic forces. In the Magnetically Assisted Gasification (MAG) process, solids are first entrapped by filtration, and then fluidized and transferred to a high temperature reactor where they are thermally decomposed. The maximum particle loading for the filter bed is determined by the intergranular void space. Using magnetic methods, it is possible to manipulate the degree of compaction as the filtration progresses to increase the void space and thereby maximize the loading capacity and efficiency of the filter. This process is completely compatible with operation in microgravity and hypogravity.

A variety of techniques, including supercritical water oxidation, fluidized bed combustion, and microwave incineration have been applied to the destruction of solid wastes produced in regenerative life support systems supporting long duration manned missions. Among potential problems which still deserve attention are the need for operation in a variety of gravitational environments, and the requirement for improved methods of presenting concentrated solids to the reactor. Significant improvements in these areas are made possible through employment of the magnetically assisted gasification process. In this paper, magnetic methods are described for manipulating the degree of consolidation or fluidization of granular ferromagnetic media, for application in a gravity independent three step solid waste destruction process.