Absolute property measurements using electromagnetic sensors
US7696748B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 2004 |
| Grant date | Apr 13, 2010 |
| Priority date | — |
| Expiry date | Nov 14, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/9046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus are described for absolute electrical property measurement of materials. This is accomplished with magnetic and electric field based sensors and sensor array geometries that can be modeled accurately and with impedance instrumentation that permits accurate measurements of the in-phase and quadrature phase signal components. A dithering calibration method is also described which allows the measurement to account for background material noise variations. Methods are also described for accounting for noise factors in sensor design and selection of the optimal operating conditions which can minimize the error bounds for material property estimates. Example application of these methods to automated engine disk slot inspection and assessment of the mechanical condition of dielectric materials are presented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.