Performance of manpack electromagnetic location equipment in trapped miner location tests
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields

Language:

Dates

Publication Date Range:

to

Document Data

Title:

Document Type:

Library

Collection:

Series:

People

Author:

Help
Clear All

Query Builder

Query box

Help
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Performance of manpack electromagnetic location equipment in trapped miner location tests

Filetype[PDF-1010.41 KB]


  • English
    • Details Related Documents You May Also Like

    Details:

    • Personal Author:
      Farstad, Arnold J.
    • Conference Authors:
      Thru-the-Earth-Electromagnetics Workshop (1973 : Colorado School of Mines)
    • Description:
      The use of radio signals for underground communications was considered as early as the mid-1920's [1] - [4] . However, early experiments did not produce promising results with the type of equipment that was available then [5] . With advancements in solid state technology many of the schemes considered impractical in the early days suddenly became practical. The properties of electromagnetic wave behavior in conducting media have been intensively studied by Wait [ 6] and others and can be utilized not only in communication with trapped miners, but also as a means of locating their position. This report deals with the development of portable electromagnetic equipment, powered by the miner's conventional lamp battery, which can be used to alert surface rescue personnel of the trapped miner Is location. The Westinghouse Georesearch Laboratory (WGL) under BUMINES sponsors hip initially approached the trapped miner location problem using seismic techniques. It was learned from this effort that two serious shortcomings of seismic techniques are (1) the extremely weak signals available on the surface from miner generated hammer blows, requiring long processing times at the surface receiver, and (2) the relatively slow procedure of deploying geophone arrays to sense the seismic uplink signals. By contrast, the electromagnetic techniques have proven much more practical from a deployment time standpoint and in most cases have also proven to be more accurate in determining location. Furthermore, these techniques have been successfully tested using a receiver in a heli- copter for reconnaissance purposes. However, before any electromagnetic location technique can become fully operational, the miners themselves must be equipped with emergency transmitters to be carried with them on each work shift. Consequently, much emphasis has been placed on the development of extremely lightweight transmitting equipment. The performance of some of the electromagnetic location equipment developed by Westinghouse will be described in the following sections. 2.0 Basic Concepts Theoretical concepts for locating magnetic dipoles in the earth have been treated by Wait [ 7] and Olsen [ 8] .
    • Source:
      Proceedings of Thru-the-Earth Electromagnetics, August 15-17,1973, Colorado School of Mines, p. 62-72
    • Series:
      Proceedings of Thru-the-Earth Electromagnetics, August 15-17,1973, Colorado School of Mines
    • Document Type:
      Book Chapter
    • Genre:
      Conference Publications
    • Collection(s):
    • Main Document Checksum:
    • Download URL:
    • File Type:

    Supporting Files

    • No Additional Files

    More +

    Related Documents

    You May Also Like

    Checkout today's featured content at stacks.cdc.gov