摘要 |
A method and apparatus for determining the position and orientation of a remote object relative to a reference coordinate frame includes a source having a plurality of field-generating elements for generating electromagnetic fields, a drive for applying, to the generator element, signals that generate a plurality of electromagnetic fields that are distinguishable from one another, a remote sensor having a plurality of field-sensing elements for sensing the fields generated by the source, and a processor for processing the outputs of the sensing elements into remote object position and orientation relative to the source reference coordinate frame. The processor compensates the position and orientation values as a function of displacement of either the field-generating elements from a common center, or the field-sensing elements from a common center, or both. Techniques are disclosed for compensating for small-scale non-concentricity in order to overcome imperfections in the orthogonal coil sets wound on a common core, each set defining the source or the sensor. Techniques are also disclosed for compensating for large-scale non-concentricity to allow physical separation of the coil set defining the source or the sensor to dispersed locations that may be more desirable for a particular application.
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