05142506 is referenced by 113 patents and cites 12 patents.

A positional locating method and apparatus (10) for measuring distances by accurately determining the transit time of ultrasonic wave bursts (22) between two or more points is disclosed. Timer clocks (60), (62), (64) and (66) are started when each of the bursts (22) is triggered to be emitted from a transmission point (14), and are stopped when a highly defined point (56) in the burst (22) is received at a corresponding receiving point (32), (34), (36) and (38). The highly defined point (56) is determined by first analyzing the burst (22) to identify a particular cycle (54) within the burst (22). That particular cycle (54) is then analyzed to detect the specific point (56) within the cycle (54). Use of multiple transmitters (9312), (9314) and (9316) or receivers (932), (934) and (936) permits the dimensions using ordinary trigonometric calculations. The calculation of position within two or three physical inventive method also has sufficient resolution to permit the calculation of attitudinal data by detecting very fine positional differences in a plurality of reference points located at relatively close distances on a movable marker device (912).

Title
Ultrasonic position locating method and apparatus therefor
Application Number
7/601942
Publication Number
5142506
Application Date
October 22, 1990
Publication Date
August 25, 1992
Inventor
Bruce H Edwards
Santa Clara
CA, US
Agent
Townsend and Townsend
Assignee
Logitech
CA, US
IPC
G01S 3/80
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