Subterranean course alignment laser instrument
AssigneeThe United States of America as represented by the Secretary of the Air Force
InventorRonald W. Dennis
Life of this patent
Estimating the term…
Abstract
A subterranean course-defining laser instrument and a system for initial calibration or setup of this instrument to provide accurate definition of a sub surface course for a pipeline or the like. Instrument setup is made in response to an above-ground course definition marker such as a surveyor's stake or surveyor's rod. A double mirror pseudo periscope arrangement is used to enable optical signal communication from the subterranean location of the laser instrument to the above ground marker with each of the mirrors being of a curved and error-minimizing nature. Details regarding two major components of the apparatus and quantitative consideration of achieved error budget are included.
Claims20
Surface-referenced pipeline subterranean azimuth course-determining laser apparatus comprising the combination of:
- a first laser element disposed in a subterranean receptacle and generating subterranean receptacle-contained horizontally directed radiant energy emission at an output port thereof;
- a desired pipeline azimuth course marker element disposed at a surface reference location distal of said subterranean receptacle;
- first curved mirror apparatus selectively coupled to said output port of said first laser element and selectively directing said subterranean receptacle-contained horizontally directed radiant energy emission upward and out of said subterranean receptacle;
- second curved mirror apparatus disposed above said subterranean receptacle and said first laser element and orienting said upward and out-directed first laser element radiant energy parallel with said first laser element horizontally directed radiant energy emission away from said subterranean receptacle in an above ground selected azimuth direction toward said desired pipeline course marker element;
- said subterranean receptacle-contained first laser element horizontally directed radiant energy emission selectively designating a desired subterranean azimuth course for said pipeline in response to prior optimized receipt of said first laser radiant energy at said desired pipeline course marker surface reference element via said first curved mirror apparatus and said second curved mirror apparatus.
The method of aligning a subterranean course-identifying laser azimuth guidance instrument to a pipeline course-determining surface-received course marker, said method comprising the steps of:
- disposing said subterranean course-identifying laser azimuth guidance instrument, and a surmounted curving mirror comer reflector member optically communicating therewith, in earth-parallel planes located within and passing above an earthen receptacle;
- diverting laser beam output radiant energy from an earthen receptacle wall-illuminating first orientation parallel with said earth-parallel planes in said earthen receptacle to a second orthogonal orientation intercepting an input port of said surmounted curving mirror corner reflector member;
- directing said surmounted curving mirror corner reflector member input port radiant energy from an output port of said surmounted curving mirror corner reflector member along an earth-parallel plane toward said course marker;
- aligning said subterranean laser azimuth guidance instrument to an azimuth position achieving aligned maximum illumination of said course marker by said surmounted curving mirror corner reflector output port radiant energy;
- returning said laser beam output radiant energy to a non-diverted receptacle wall-illuminating orientation determinative of said pipeline course without disturbing said subterranean laser azimuth guidance instrument alignment.
Surface reference marker-guided pipeline subterranean azimuth course-identifying laser instrument apparatus comprising the combination of:
- first laser apparatus disposed in an earthen receptacle and generating earthen receptacle-contained horizontal component-inclusive laser energy emission at a laser output port;
- a desired pipeline subterranean azimuth course marker element disposed at an earth surface-received location removed from said earthen receptacle;
- pivotally mounted concave bevel curved mirror apparatus selectively coupleable to said laser output port and thereby, during a laser instrument apparatus alignment sequence, electively directing said earthen receptacle-contained horizontal component-inclusive laser energy emission in a vertical component-inclusive upward direction out of said earthen receptacle;
- convex bevel curved mirror apparatus disposed above said earthen receptacle and said first laser apparatus and orienting said vertical component-inclusive upward direction first laser apparatus radiant energy, during said alignment sequence, away from said earthen receptacle in an above-ground azimuth direction toward said earth surface-received desired pipeline subterranean azimuth course marker element;
- alignment adjustment apparatus connected with said earthen receptacle-disposed first laser apparatus and enabling, during said alignment sequence, optimum alignment of said first laser apparatus radiant energy with said earth surface-received desired pipeline subterranean azimuth course marker element;
- said earthen receptacle-contained first laser apparatus horizontal component-inclusive radiant energy emission selectively designating, following said alignment sequence, a desired subterranean azimuth course for said pipeline, in response to said optimum alignment of said first laser apparatus radiant energy with said earth surface-received desired pipeline subterranean azimuth course marker element via a pseudo periscope comprised of said concave curved mirror apparatus and said convex curved mirror apparatus.
Dependencies are inferred from the claim text.