Patent US3918172A successfully refreshed from Google Patents.
US3918172A
Expired / Lapsed
US
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Method and apparatus for determining geodesic measurements by helicopter
Assignee: Hydro-Québec
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Filing: 1973-12-26
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Granted: 1975-11-11
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Expires: 1993-12-26
Abstract
Abstract The present invention concerns a method for determining the geographical characteristics of a number of points of a terrain, and to an apparatus particularly adapted to carry out this method. The system comprises a laser beam transmitter placed on ground at a point to be defined, which beam is detected by means of an airborne device constituted of convergent or divergent lens and mirrors disposed so as to permit the pilot of a helicopter to visualize the beam. This system permits the accurate positioning of the helicopter above the point to be defined. The different angles and distances are obtained by means of instruments, such as a tellurometer and a theodolite placed at a known point of the terrain. However, to obtain the differences in level between the helicopter and the point to be defined, a transmitter-receiver of infrared beams capable of transmitting through a mirror a vertical beam which is reflected by a reflecting plate mounted under the helicopter is provided.
Inventors
- 👤 Richard Moreau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:35
CPC Classifications
G; G01; G01C; G01C15/00; G01C15/002
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
134 words
A system for determining the geographical position of a point located at a remote station from a reference point at a base station, comprising a helicopter at said remote station; a light source capable of producing a beam of monochromatic rays, said beam being vertically directed towards the helicopter; a transparent plate having angularly disposed on one surface thereof a plurality of parallel reflecting means, said plate being mounted at the front end of the helicopter so as to permit the helicopter pilot to directly visualize said light beam striking the transparent plate and being then reflected by the parallel reflecting means towards the pilot, thereby indicating that the helicopter is substantially vertically positioned over said remote point; instrument means at the base station and on the helicopter for taking angle and distance measurements.
Claim 2
Independent Claim
134 words
A system for determining the geographical position of a point located at a remote station from a reference point at a base station, comprising a helicopter at said remote station; a light source capable of producing a beam of monochromatic rays, said beam being vertically directed towards the helicopter; a transparent plate having angularly disposed on one surface thereof a plurality of parallel reflecting means, said plate being mounted at the front end of the helicopter so as to permit the helicopter pilot to directly visualize said light beam striking the transparent plate and being then reflected by the parallel reflecting means towards the pilot, thereby indicating that the helicopter is substantially vertically positioned over said remote point; instrument means at the base station and on the helicopter for taking angle and distance measurements.
Claim 3
Dependent Claim
15 words
System as claimed in claim 1, wherein said light source is a laser beam transmitter.
Claim 4
Dependent Claim
42 words
System as claimed in claim 1, wherein the distance between the helicopter and the remote point is determined by means of an infrared ray transmitter-receiver set at said remote station, a reflector being mounted under the helicopter for reflecting the infrared rays.
Claim 5
Dependent Claim
41 words
System as claimed in claim 1, wherein the distance between the helicopter and the reference point is determined by means of a microwave device set at said base station, said device being coupled with a parabolic antenna mounted on the helicopter.
Claim 6
Dependent Claim
29 words
System as claimed in claim 1, wherein angles are measured by means of a theodolite provided at the base station and coupled to a strobelite mounted on the helicopter.
Claim 7
Dependent Claim
25 words
System as claimed in claim 1, wherein the surface opposite to said one surface of said transparent plate includes a plurality of lens embedded therein.
Claim 8
Dependent Claim
15 words
System as claimed in claim 6, wherein each of said lens has a concave surface.
Claim 9
Dependent Claim
20 words
System as claimed in claim 6, wherein each of said lens has a convex surface and a small focal length.
Claim 10
Dependent Claim
51 words
System as claimed in claim 1, wherein said parallel reflecting means are mirrors and are divided into three groups, each of the groups including a predetermined number of parellel mirrors and each of the mirrors of a given group being angularly set with respect to a mirror of an adjacent group.
Claim 11
Dependent Claim
95 words
A light beam detector, comprising a panel made of transparent plastic material, said panel having refringent elements on one surface thereof, the other surface being substantially flat; and reflecting means mounted on and at an angle to said flat surface of the transparent panel, said reflecting means being divided into three distinct groups, each of said groups including a predetermined number of parallel reflecting means each of which standing at a given angle to a reflecting means of an adjacent group, thereby reflecting in a predetermined direction the light beam diffused through said Refringent elements.
Claim 12
Dependent Claim
95 words
A light beam detector, comprising a panel made of transparent plastic material, said panel having refringent elements on one surface thereof, the other surface being substantially flat; and reflecting means mounted on and at an angle to said flat surface of the transparent panel, said reflecting means being divided into three distinct groups, each of said groups including a predetermined number of parallel reflecting means each of which standing at a given angle to a reflecting means of an adjacent group, thereby reflecting in a predetermined direction the light beam diffused through said Refringent elements.
Claim 13
Dependent Claim
29 words
A detector as claimed in claim 10, characterized in that each of said refringent elements has a concave surface, said elements covering substantially said one surface of the panel.
Claim 14
Dependent Claim
34 words
A detector as claimed in claim 10, characterized in that each of said refringent elements has a convex surface and a small focal length, said elements covering substantially said one surface of the panel.
Claim 15
Dependent Claim
43 words
A detector as claimed in claim 10, characterized in that said given angle is approximately of 10*, and that the angle between one of said reflecting means and a perpendicular drawn from said flat surface of the panel varies from 1* to 10*.
Claim 16
Dependent Claim
66 words
A light beam detector, comprising a panel made of transparent plastic material, said panel having refringent elements on one surface thereof, the other surface of said panel being flat; and a plurality of concave reflecting means mounted on and at an angle to said flat surface of the transparent panel so as to reflect in a predetermined direction the light beam diffused through said refringent elements.
Claim 17
Dependent Claim
66 words
A light beam detector, comprising a panel made of transparent plastic material, said panel having refringent elements on one surface thereof, the other surface of said panel being flat; and a plurality of concave reflecting means mounted on and at an angle to said flat surface of the transparent panel so as to reflect in a predetermined direction the light beam diffused through said refringent elements.
Claim 18
Dependent Claim
36 words
A detector as claimed in claim 14, characterized in that each of said parallely mounted reflecting means makes an angle with a perpendicular drawn from said flat surface of the panel varying between 1* and 10*.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |