04613866 is referenced by 239 patents and cites 29 patents.

A three dimensional digitizer is provided for determining and digitizing the coordinates of a three dimensional object. A hand-held stylus is used for tracing and determining points of interest on the surface of the object. A plurality of antennas for radiating electromagnetic energy are provided, the antennas being embedded in a table having a work surface upon which the object is placed. The radiating antennas have independent components which define a reference coordinate frame. A transmitter applies electrical signals to the radiating antennas which generate a plurality of distinguishable radio frequency electromagnetic fields. The stylus is provided with a projection for defining a point of contact between the stylus and the surface of the object of interest. A plurality of receiving antennas are disposed in the stylus. The receiving antennas have a known relationship with the projection and the point of contact on the object. The receiving antennas are provided with a plurality of independent components for detecting each of the transmitted electromagnetic fields. The output of the receiving antennas is supplied to an analyzer which converts the components of the electromagnetic fields received by the receiving antennas into the remote position and orientation of the receiving antennas relative to the reference coordinate frame. Since the point of contact of the stylus and the receiving antennas are provided with a known relationship, the coordinates of the surface of the three dimensional object touched by the stylus are also determined in the analyzer.

Title
Three dimensional digitizer with electromagnetic coupling
Application Number
6/494292
Publication Number
4613866
Application Date
May 13, 1983
Publication Date
September 23, 1986
Inventor
Ernest B Blood
Burlington
VT, US
Agent
Price Heneveld Huizenga & Cooper
Assignee
McDonnell Douglas Corporation
MO, US
IPC
G01B 7/14
G01S 5/04
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