Publications de Pavel Kejik | EPFL Graph Search

The High-Resolution Magnetic Camera: A Novel Sensor for Eddy Current Testing

Hannes Bleuler, Roland Moser, Marco Picasso, Pavel Kejik, Gilles Raphaël Santi, David Florian Hippert

Eddy current techniques are often used to detect and, in some advanced applications, to characterize fatigue surface-breaking cracks appearing in mechanical parts. One of the major difficulties in this approach is to reliably separate the crack contributio ...

Ios Press2014

Characterization of Surface Cracks Through The Local Magnetic Field Induced by Eddy Currents

Hannes Bleuler, Roland Moser, Marco Picasso, Pavel Kejik, Gilles Raphaël Santi, David Florian Hippert

It is important to reliably characterize cracks in metallic mechanical parts in order to assess the serenity of damage due to fatigue. The most important parameter for this is the crack depth. This is notoriously difficult with standard Eddy current techni ...

Ios Press2014

Offset Compensation Based on Distributed Hall Cell Architecture

Pierre-André Farine, Pavel Kejik, Pierre-François Thibault Bourdelle

A new offset reduction strategy for CMOS Hall devices is proposed. The novelty is to fragment the Hall device into multiple Hall blocks, distributed over the silicon area and easy to interconnect. The suitable number of Hall blocks and the bias current lev ...

Institute of Electrical and Electronics Engineers2013

Layout and Architecture Issues in Hall based CMOS microsystems

Pierre-André Farine, Pavel Kejik

The Hall cells intended for industrial applications are mainly produced in silicon integrated circuit technology. Recently, the increased use of other technologies, such as GaAs, InAs and InSb, have been reported. However, a single chip solution comprising ...

Czech Technical University in Prague, Faculty of Electrical Engineering2012

An Integrated Probe for Electromagnetic NDT Inspection

Pavel Kejik

Electromagnetic techniques present definite advantages for Non Destructive Testing such as no need for surface couplant, potential for miniaturization, and fast scanning rates. They suffer, however, from a lack of reliability when crack sizing capabilities ...

2010

Offset compensation based on distributed Hall system architecture

Radivoje Popovic, Pavel Kejik

Integrated Hall devices have the great advantage, over other magnetic sensors, that they can be fully fabricated by a standard CMOS process. However they are known to have a relatively large offset (i.e. residual voltage at zero magnetic field). Techniques ...

2010

Hall sensor array

Pavel Kejik

Integrated circuit Hall sensor system comprising a plurality of elementary blocks (EB), each elementary block including a Hall cell (4), a differential pair (8) of an input stage of a Differential Difference Amplifier (DDA), and terminals (12a, 12b), where ...

2010

Ultra Low-Power Angular Position Sensor for High-Speed Portable Applications

Radivoje Popovic, Pavel Kejik

We present a technique for contactless angular position sensing that allows low power consumption while keeping dynamic properties comparable to existing sensors. The technique essentially consists in combining a recently developed sensing element, the so- ...

IEEE Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009

Orthogonal fluxgate magnetic field sensor

Pavel Kejik, Ozge Zorlu

Orthogonal fluxgate sensor for measuring an external magnetic field Hext, comprising a conductor for carrying an excitation current lexc, a ferromagnetic material adapted to saturate in the presence of a magnetic field generated by the excitation current, ...

2009

Micro Fluxgate Sensor with Cascaded Planar Ring Cores

Pavel Kejik, Ozge Zorlu

In this paper, we present a new microfabricated fluxgate sensor structure having cascaded planar rings as the ferromagnetic core. A circular magnetic excitation is provided with a rod passing through the FeNi rings as a sewing thread. Planar coils placed u ...

2009