AERIAL SURVEY

• US 3,709,607 A
• Filed: 08/19/1970
• Issued: 01/09/1973
• Est. Priority Date: 08/19/1970
• Status: Expired due to Term

• Current Assignee: Frederick C. Mcconnell, George Jason, Neil J. Armstrong
• Original Assignee: Frederick C. Mcconnell, George Jason, Neil J. Armstrong
• Inventors: McConnell, Frederick C., Jason, George, Armstrong, Neil J.
• Primary Examiner(s): Borchelt, Benjamin A.
• Assistant Examiner(s): Buczinski, S. C.
• Application Number:
  US05/065,259
• Time in Patent Office: 874 Days
• Field of Search: 356/4,5,141,152,138,172 250/23R,215 244/17.11,17.17 33/1T
• US Class Current: 356/141.3
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105

Abstract

The invention provides a target positioning apparatus adapted to aid in the survey location of a predetermined point therebeneath. The apparatus includes a helicopter plus means on the helicopter enabling the pilot to view the terrain beneath it, and a laser alignment and device capable of indicating when the helicopter is positioned vertically over the point whose location it is desired to fix by survey. The laser alignment device includes a laser capable of projecting a laser beam directed vertically between the helicopter and the survey point. An image of the laser beam superimposed on an image of the terrain is displayed in the cockpit of the helicopter.

Claims

1. Target positioning apparatus for use in aerial surveying comprising a helicopter, means mounted on said helicopter enabling the pilot thereof to view the terrain beneath the helicopter when it is airborne, and laser alignment means for indicating when said helicopter is positioned vertically over a point on the terrain whose location it is desired to fix by survey, said laser alignment means including a laser capable of projecting a laser beam directed vertically between said helicopter and said point, a laser detector for detecting the laser beam, one of said laser and said laser detector being mounted on said helicopter and means for indicating to the pilot when the laser beam is aligned with said laser detector.

2. Target positioning apparatus as defined in claim 1, wherein said one of said laser and said laser detector mounted on said helicopter is aligned with the line of sight of said terrain viewing means.

3. Target positioning apparatus as defined in claim 1, wherein said terrain viewing means include display means for displaying an image of said terrain to the pilot, and said laser beam indicating means are combined with said display means to provide an image of the laser beam coincident with the image of the terrain.

4. Target positioning apparatus as defined in claim 1, wherein said laser detector is mounted on said helicopter, and further comprising electric circuit means connected to said laser detector for providing an output signal in response to alignment of the laser beam with said laser detector, and a sighting device operable in response to the output signal of said electric circuit means to provide a visual sighting point.

5. Target positioning apparatus as defined in claim 1, wherein said laser detector is provided in said helicopter and aligned with the line of sight of said terrain viewing means and said terrain viewing means and said laser beam indicating means comprise a common display device for displaying an image of the laser beam on an image of the terrain when the laser beam at least approximately coincides with the line of sight of the terrain viewing means.

6. Target positioning apparatus as defined in claim 5, further comprising electric circuit means connected to said laser detector for providing an output signal in response to alignment of the laser beam with said laser detector, and a sighting device operable in response to the output signal of said electric circuit means to provide a visual sighting point.

7. Target positioning apparatus as defined in claim 1, further comprising an electrical switching circuit actuatable in response to incidence of the laser beam on said laser detector, and surveying equipment on said helicopter operable in response to actuation of said electrical switching circuit.

8. Target positioning apparatus as defined in claim 1, wherein said laser beam detector comprises first and second groups of photocells each of said groups being distributed in a circle around and fixed relative to the line of sight of said terrain viewing means and said first group being nearer thereto than said second group, electrical switching means are connected to said first and second groups of photocells, and surveying equipment on the helicopter is controlled by said electrical switching means, whereby said electrical circuit is adapted to change the switching state thereof and to correspondingly control the surveying equipment in response to movement of the laser beams from one of said first and second groups of photocells to the other.

9. Target positioning apparatus as defined in claim 6, further comprising an electrical switching circuit actuatable in response to incidence of the laser beam on said laser detector, and surveying equipment on said helicopter operable in response to actuation of said electrical switching circuit.

10. Target positioning apparatus as claimed in claim 6, wherein said laser beam detector comprises first and second groups of photocells, each of said groups being distributed in a circle around and fixed relative to the line of sight of said terrain viewing means and said first group being nearer thereto than said second group, electrical switching means are connected to said first and second groups of photocells, and surveying equipment on the helicopter is controlled by said electrical switching means, whereby said electrical circuit is adapted to change the switching state thereof and to correspondingly control the surveying equipment in response to movement of the laser beam from one of said first and second groups of photocells to the other.