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Continental Automotive Systems started development of an electromechanical brake-by-wire system (EMB) 2 years ago. A major part of the development deals with the control of the brake actuator. For the development of control algorithms a special test stand was built. It consists of the seat capsule, the actuator and the PC-based electronic control unit. As the electronic unit also performs a real time vehicle and actuator simulation a complete Hardware-in- the-Loop system supports simultaneous engineering within this project. This paper describes the Hardware-in-the-Loop development system and shows first results obtained in an early state of the development process.

With the aim of producing innovative clutch actuation mechanisms for automotive transmissions, we are investigating a design based on power screws. The design strives to improve clutch actuation technology and minimize energy consumption by maintaining clutch lock-up independent of an external energy source. The system consists of a lead screw shaft-and-nut assembly, a clutch apply-plate, a set of wet clutch disks and a brushless DC motor. The clutch actuation assembly is separated from the clutch-pack via thrust bearings, which allows the use of a motor, while reducing the inertial load imposed by the conventional clutch-pack. A prototype of the design was fabricated and installed on a testbed, to mimic the installation of the actuator to replace the hydraulic components. A standard 12-disk clutch-pack of an automatic transmission was used within the apparatus. The formulation of the mathematical model of the entire testbed is described in this paper.

This paper describes the feasibility of a de-icing device based on forced vibrations induced in an ice-covered rectangular aluminum plate using an amplified piezoelectric actuator. The removal of the ice layer is caused by the creation of mechanical stresses induced by relatively fast time-varying mode shapes in the very low kHz-range large enough to overcome the adhesion forces at the material/ice interface.

This paper presents a multi-physic modeling of an electromechanical energy scavenging device able to supply energy inside car tires for wireless sensors. A permanent magnet, connected to the inner liner of a tire, is accelerated along a guide by the tire deformation during car motion; by interacting with coils it generates a power which is conditioned by a proper electronic interfaced to an external load. The original approach implemented in this kind of device is the nonlinear dynamic properties designed and controlled: adaptive resonance in function of car velocity is optimized for increasing its global efficiency. The energy conversion process takes into account the simulation of different phenomena such as: non linear dynamic and adaptive resonant behavior of the seismic mass, electromagnetic and magneto-static coupling between moving mass and coils, transfer of the generated power to an external load by means of a nonlinear circuit interface.

The new rare-earth sammarium-cobalt magnets are revolutionizing electromechanical actuation design to the extent that power-by-wire can be a legitimate follow-on to fly-by-wire. These new magnets coupled with innovative design techniques which feature direct interface with fly-by-wire are creating electromechanical actuator designs that are highly competitive to hydraulic actuators in terms of weight, space, and performance. A major promise of these new electromechanical actuators is to permit unification of total secondary power systems under a single medium, electrical.

The new rare-earth sammarium-cobalt magnets are revolutionizing electromechanical actuation design to the extent that power-by-wire can be a legitimate follow-on to fly-by-wire. These new magnets coupled with innovative design techniques which feature direct interface with fly-by-wire are creating electromechanical actuator designs that are highly competitive to hydraulic actuators in terms of weight, space, and performance. A major promise of these new electromechanical actuators is to permit unification of total secondary power systems under a single medium, electrical.

Four independent guidance fin actuation subsystems have been packaged in an air vehicle section only four inches in diameter. The Control Actuation Section (CAS) of the IRTGSM submunition is seven and one half inches long. Within this envelope are the four electromechanical actuators, three thermal batteries, Flight Control Element Electronic (FCEE) module, four guidance fins (in the retracted position), and connector and structural interfaces. Location of the CAS and the air vehicle are shown in Figure 1.

Many researches focus on piezoelectric ice protection systems with the objectives to develop light and low consumption resonant electromechanical systems for de-icing. These systems use the vibrations generated by piezoelectric actuators at resonance frequencies to produce shear stress at the interface between the ice and the support or to produce tensile stress in the ice. This article presents experimental results of de-icing tests performed with resonant piezoelectric systems that generate amplitudes of vibrations to exceed ice tensile strength or ice/support adhesive shear strength. The tests show that fractures are initiated but that the ice is not always completely detached. A methodology based on the energy release rate is presented to enable a better understanding of fractures initiation and propagation.

The University of Texas Center for Electro-mechanics (UT-CEM) has been developing active suspension technology for high-speed off-road applications since 1993. The UT-CEM system uses controlled electromechanical actuators to control vehicle dynamics with passive springs to support vehicle static weight. The program is currently in a full vehicle demonstration phase on a military high mobility multipurpose wheeled vehicle (HMMWV). This paper presents detailed test results for this demonstration vehicle, compared to the conventional passive HMMWV, in a series of tests conducted by the U.S. Army at Yuma Proving Grounds. Extensive data in plotted form are discussed, including accelerometer readings from 6 vehicle mounted accelerometers, corner displacement transducers, and current and power plots for the actuators.

The use of electromechanical actuators for an active suspension on a main battle tank is investigated. A novel approach to the development of the active suspension control algorithms is presented along with simulation results to evaluate the electromechanical design requirements. The optimal electromechanical actuator design is described along with simulated performance results for a one roadwheel station electromechanical active suspension. Follow-up plans for the laboratory testing of a single wheel station system are also included.

The combination of an inherently robust asynchronous (induction) electrical machine with the rapid control of energy provided by a high frequency resonant ac link enables the efficient management of higher power levels with greater versatility. This could have a variety of applications from launch vehicles to all-electric automobiles. These types of systems utilize a machine which is operated by independent control of both the voltage and frequency. This is made possible by using an indirect field-oriented control method which allows instantaneous torque control in all four operating quadrants. Incorporating the ac link allows the converter in these systems to switch at the zero crossing of every half cycle of the ac waveform. This “zero loss” switching of the link allows rapid energy variations to be achieved without the usual frequency proportional switching loss.

Power modules are used to operate three-phase alternating current motors in hybrid vehicles and electric vehicles. Good fuel efficiency and high power density are required in the field of hybrid vehicles. To achieve this goal, the miniaturization of the power module will be necessary. This trend may make a current density, which is created by insulated gate bipolar transistors (IGBTs) and free wheel diodes (FWDs), higher in power modules. Solder is often used as the joint material of power modules. It is known that a current density larger than 10 kA/cm2 causes solder electromigration. This phenomenon may cause delamination of the joint area. In addition, the ambient temperature has an influence on electromigration. The temperature of an engine compartment is high, so it is likely to cause electromigration. However, the current density of the double-sided cooling power modules in 2007 with solder joint is lower than 0.4 kA/cm2, and this value is lower than 10 kA/cm2.

Lateral head motions, torso motions, lateral neck bending angles, and electromyographic (EMG) activity patterns of five human volunteer passengers are compared to lateral motions of a Hybrid III ATD during right-left and left-right fishhook steering maneuvers leading to vehicular tip-up. While the ATD maintained relatively fixed lateral neck angles, live subjects leaned their heads slightly inward and actively utilized their neck musculature to stiffen their necks against the lateral inertial loads. Except for differences in neck lateral bending, the Hybrid III ATD reasonably reflects occupant kinematics during the pre-trip phase of on-road rollovers.

Tomorrow's vehicles will offer increased comfort and luxury features to drivers. These features will require the use of additional electrical circuits within the same space that is available in today's vehicles. In order to meet these requirements, a new, compact, high temperature wire design will be required. Insulation utilizing electron beam cured polyethylene offers the required product features, while also offering the processability required for this type of wire. This paper will address why this material is best suited for this task, describe how a product of this type can be evaluated, and provide a comparison between a compound of this type and the current industry standard.

In the frame of military programmes, AEROSPATIALE, developed, for ballistic missiles (motor cases wound structures), an original process of composites curing. This process, now utilized on an industrial basis is the Electron Beam Curing (EBC, sometimes called ionization, or irradiation curing). EBC is based on the composite's resin polymerization caused by its exposure under a powerful enough electron beam. Originally, this process was developed for costs saving reasons, as an economical alternative to the conventional thermal curing process. This objective having been achieved, an other incentive was found to the use of such a technology. As a matter of fact, this process offers the outstanding advantage of being a “room temperature” process. The electron beam acts directly on resins molecular structure to bring about its polymerization, no heating of the part is necessary.

Electron beam curing is a very fast, non-thermal curing method that uses high energy electrons and/or X-rays as ionizing radiation at controlled rates to cure polymer matrix composites, making them more affordable. A number of programs and initiatives are now actively evaluating the materials and processes for applications as varied as next generation aircraft, space transportation, military ground vehicles, and others. This technology offers a variety of potential benefits to the transportation industry.

This paper discusses electron beams and their generation, configuration of electron beams used for welding, sources for electron beam information and manufacturers of electron beam welding machines, tooling for electron beam welding, accomplishments with electron beams in joining aerospace materials, and the future of electron beams in welding technology.

The characteristics and advantages of electron beam welding using both vacuum and nonvacuum techniques are discussed and related to the use of this process in production. Specific applications of both techniques are selected and described in detail as a means of evaluating this process relative to quality, versatility, controllability, adaptability for automation, and economics.

Some of the characteristics of electron beam welding are presented which can be exploited by the design engineer, together with precautionary notes on limitations. Specific examples of electron beam welded aircraft components arecited.

The conversion from submerged arc welding to electron beam welding (EBW) of transmission components at Clark Equipment Co. is described. The latter system permits the consistent holding of close tolerances and the obtaining of controllable and repeatable metallurgical structures. In addition, control of the weld and distortions is increased, and weld joints are made feasible in otherwise inaccessible locations. A brief history is presented which touches on the selection of transmission products for EBW, choice of EBW equipment, preliminary evaluation, and acceptance of the process by personnel. Then, the application of EBW to production parts is discussed.