04394831 is referenced by 41 patents and cites 6 patents.

An electromagnetic system for determining the orientation including position of a helmet worn by a pilot is disclosed having a transmitting antenna for transmitting electromagnetic field vectors, a receiving antenna for sensing the electromagnetic field vectors generated by the transmitting antenna, and a control apparatus responsive to the sensed electromagnetic field vectors and the transmitted electromagnetic field vectors for determining the compensated orientation of the helmet, the compensated orientation relying upon the rotation matrix determined by a previous solution for the orientation of the helmet.

Title
Helmet metal mass compensation for helmet-mounted sighting system
Application Number
6/233747
Publication Number
4394831
Application Date
February 12, 1981
Publication Date
July 26, 1983
Inventor
E Jack Weir
Roseville
MN, US
Jeffrey M Setterholm
Minnetonka
MN, US
Werner H Egli
Minneapolis
MN, US
Agent
Trevor B Joike
Assignee
Honeywell
MN, US
IPC
G01R 33/02
F41G 9/00
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