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    Neil Armstrong's Root Locus Spirule, Directly From The Armstrong Family Collection™, CAG Certified. Sized 11.5" x 4.75", produced by the Spirule Company in Whittier, CA, copyright 1959, North American Aviation, Inc. This simple device used by Armstrong is a special protractor that aids in the determination of angles and root loci. A printed photocopy of the Spirule's user manual, including diagrams and descriptions, accompanies the device.

    Root locus analysis is used in stability and control theories, to examine how the root of a system can change with variations to system parameters. The technique was developed by Walter R. Evans in 1948. Evans (1920-1999) was a noted American engineer who worked at companies such as General Electric, Rockwell International, and Ford Aeronautic Company. He developed this device in the 1960s and 100,000 of them were made and sold before the use of personal computers became preferable. Very good with minor wear. Sealed in a numbered archival holder, CAG 1002039-006. This lot will include a Statement of Provenance signed by Neil Armstrong's sons, Rick and Mark.

    Learn more about Collectibles Authentication Guaranty (CAG).

    Auction Info

    Auction Dates
    July, 2019
    16th-18th Tuesday-Thursday
    Bids + Registered Phone Bidders: 12
    Lot Tracking Activity: N/A
    Page Views: 1,298

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