Gain factor and position determination system

US6625563B2 · kind B2 · utility

Assignee

• Northern Digital Inc. · CA

Inventors

• Stefan Kirsch · Heidesheim, DE
• Hans R. Schild · Uetikon am See, CH
• Christian Schilling · Brugg, CH

Key dates

• Filing date: Jun 26, 2001
• Grant date: Sep 23, 2003
• Expiry date: Jun 26, 2021

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B5/062
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A system for determining the position, orientation and system gain factor of a probe includes a plurality of magnetic field sources and at least one magnetic field sensor, such that a combination of a magnetic field sensor and a magnetic field source generates a unique measured magnetic field value. The system includes a probe whose gain, position, and orientation affect these unique measured magnetic field values. A processor is configured to receive and iteratively process these unique measured magnetic field values to determine a system gain factor and a plurality of location factors. The system gain factor is indicative of the gain of the probe, and the plurality of location factors are indicative of the position and orientation of the probe. The number of unique measured magnetic field values generated must be at least equal to the sum of the number of gain and location factors calculated.