Tubular components subjected to extreme pressure and intense wear, requiring highprecision internal-diameter measurements, were investigated. Such measurements are currently carried out using slow mechanical devices and/or costly laboratory equipment. This paper describes the development process of a new measurement tool, capable of +/0.015mm diameter evaluation, using state-of-the-art eddy cur...

This report describes an eddy current system for locating distal transverse screw holes of an intramedullary nail. In fracture surgery, screw holes on an intramedullary nail are in invisible situation. Although conventional X-ray methods can visualize screw holes in bone, they pose a danger due to X-ray exposure. Therefore, a system to find screw holes without X-ray exposure is required. We sol...

We describe a sensing arrangement for detection of a metallic body rotating at high revolutions per minute (rpm) operating in dusty and muddy environment. For such an environment, the sensing range, switching frequency & ruggedness of proximity switch are key parameters. When an electrical conductor, such as a metal target enters the electromagnetic field, eddy current starts circulating in the...

We describe the use of eddy current brakes as fast turn-on, tunable, linear dampers for haptic rendering using a prototype haptic device outfitted with eddy current brakes. We show that at the speeds typically required for haptic interaction, eddy-current-induced drag is proportional to velocity. We also show that a modulation rate of approximately 250 Hz can easily be achieved with off the she...

In this contribution a force measurement system will be represented. It applies the method of eddy-current sensor testing. This measurement arrangement is able to detect dynamic tensile loads in prestressings, which are higher then 5 MPa and oscillating up to 20 Hz. Fast measurement rates and low power consumption are the main efforts of the eddy-current sensor system. Developed sensor-arrays c...

Systems that associate positions with eddy current probe readings present inspection data more directly and usefully than the more common impedance plane display. We have economically constructed such an integration of an eddy current testing device with a position feedback device which gives 0.005” achievable resolution. The position and probe readings are fed to a PC and plotted in real-time ...

New downhole turbine generator can transmit the high speed rotation of the turbine to the rotor of the generator without contact by magnetic transmission mechanism to provide continuous power. Driving torque on magnetic transmission mechanism is a key parameter. This paper mainly studies the field on magnetic transmission mechanism of downhole turbine generator by using ANSYS software. The effe...

T he size, performance and cost of a power electronic system are closely linked to the like parameters of the magnetic components. Since custom power transformers are widely used, transformer design is a frequent design process that has a signifi cant impact on system performance. Yet most high-frequency transformers use less than 25% of the available core window for effi cient current conducti...

In the computational electromagnetism community it is known how the differential formulation of an eddy-current problem, can be translated into a finite dimensional system of equations involving circulations and fluxes, by means of the so-called Discrete Geometric Approach. This is done by exploiting the geometric structure behind Maxwell’s equations. In this paper, we will show how the same Di...

M. Markl, J. Leupold, J. Hennig Diagnostic Radiology, Medical Physics, University Hospital Freiburg, Freiburg, Germany Introduction: k-space segmented time-resolved (CINE) balanced SSFP imaging is widely used in cardiac MR-imaging [1]. Drawbacks include sensitivity to the disruption of the steady state and limitations regarding non-linear k-space reordering which is problematic for SSFP imaging...