Method and system for the acquisition of high-accuracy coordinate information without the use of directed electromagnetic radiation

• US 20150233712A1
• Filed: 02/15/2015
• Published: 08/20/2015
• Est. Priority Date: 02/19/2014
• Status: Active Grant

• Current Assignee: Stephen David Knapp
• Original Assignee: Stephen David Knapp
• Inventors: Knapp, Stephen David
• Granted Patent: US 10,337,833 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F41G 3/02 using an independent line of sight
• CPC Class Codes: F41G 3/06 with rangefinder rangefinders per se G01C
• CPC Class Codes: G01C 15/00 Surveying instruments or accessories not provided for in groups G01C1/00 - G01C13/00
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves

Abstract

A method for providing highly accurate coordinates and elevation of a remote terrestrial-based location is described. The method also provides for the determination of a number of high-accuracy values including the location and elevation of the point of observation, and the distance and bearing from the point of observation to the remote location. Also described is a method for compensating for unknown effects of the associated atmospheric refractivity, and errors in input data.

Claims

1. A method of determining the coordinates of a remote location comprising the steps of determining the location and orientation of an angle measurement device, and then calculating the coordinates of the remote location based on where the shortest path from the angle measurement device intersects the terrain at which the angle measurement device is pointing.

2. A method of determining the location and orientation of the angle measurement device of claim 1, comprising the steps of:

a) calibrating the angle measurement device such that the zero degree azimuth angle is oriented toward a reference direction such as north;

b) for each of three remote reference points, calculating locations near the angle measurement device such that the bearings of the shortest paths from each of these locations to each reference point are substantially equal to as the azimuth angles measured by the angle measurement device when it is pointing at each reference point respectively;

c) repeating step b), applying positive and negative angle offsets to the measurements from the angle measurement device until the area of the geometric object created by the intersection of the shortest paths from step b) is smaller than a selected value, or until the differences between the bearings and measured angles with applied offsets are smaller than a selected value;

d) calculating a central location near the intersections of the three shortest paths from step b) which represents the determined location of the angle measurement device, and applying the desired angle offset from step c) which when combined with the measured angle from the angle measurement device represents the determined orientation of the angle measurement device relative to the reference direction from step a).

3. A method of calculating the coordinates of the remote location of claim 1, comprising the steps of:

a) identifying a point substantially on the shortest path which starts at the angle measurement device and traverses the remote location;

b) determining whether the point from step a) is above or below the surface of the terrain at that location;

c) repeating steps a) and b) until a point from step a) has been identified for which the distance between the point and the surface of the terrain is less than a selected value.

4. A method of adjusting for errors in terrain surface measurements of claim 3 comprising the steps of:

a) obtaining the coordinates of a remote location via an angle measurement device;

b) obtaining the coordinates of a remote location on an aerial imagery map that is substantially the same as the remote location from step a);

c) calculating the elevation of the remote location based on the altitude angle measured by the angle measurement device and the relative locations of the angle measurement device and the remote location;

d) subtracting the known elevation of the coordinates in step b) from the measured elevation calculated in step a) to determine an elevation offset;

e) applying the elevation offset to subsequent measurements by the angle measurement device, resulting in measured coordinates that have been adjusted for errors in terrain surface measurements.

5. A method for compensating for unknown variables that affect atmospheric refractivity of claim 3 comprising the steps of:

a) obtaining the coordinates of a remote location via an angle measurement device;

b) obtaining the coordinates of a remote location on an aerial imagery map that is substantially the same as the remote location from step a);

c) calculating the elevation of the remote location based on the altitude angle measured by the angle measurement device and the relative locations of the angle measurement device and the remote location;

d) subtracting the known elevation of the coordinates in step b) from the measured elevation calculated in step a) to determine an elevation offset;

e) applying the elevation offset to subsequent measurements by the angle measurement device, resulting in measured coordinates that have been adjusted for unknown variables that affect atmospheric refractivity.

6. A method for combining multiple elevation offsets of claim 4 comprising the steps of:

a) calculating a weighted average of the elevation offsets of claim 4 based on the proximity of the remote location to the coordinates for which each elevation offset was calculated;

b) using the weighted average of the elevation offsets from step a) as a replacement for the elevation offset of claim 4 step e), so that the weighted average of the elevation offset is used in subsequent measurements instead of a single elevation offset.

7. A method of adjusting for errors in mapping aerial imagery to the coordinate grid comprising the steps of:

a) obtaining the coordinates of a remote location via a measurement device;

b) obtaining the coordinates of a remote location from an aerial imagery map that is substantially the same as the remote location from step a);

c) calculating the distance and bearing from the coordinates obtained in step a) to the coordinates obtained in step b);

d) using the distance ‘

d’ and

bearing ‘

b’

from step c), calculate new coordinates by starting at the coordinates of the measurement device and moving the distance ‘

d’

away from the coordinates of the measurement device in the direction of bearing ‘

b’

;

e) using the new coordinates from step d) as replacement coordinates for the measurement device, obtain a new set of coordinates from the measurement device that represent the coordinates of the remote location adjusted for errors in the mapping of the digital imagery to the coordinate grid.

8. A method for combining multiple new coordinates of claim 7 comprising the steps of:

a) calculating a weighted average of the distances and bearings of claim 7 based on the proximity of the remote location to the coordinates for which each distance and bearing was calculated;

b) using the weighted averages of the distance ‘

d’ and

bearing ‘

b’

from step a), calculate new coordinates by starting at the coordinates of the measurement device and moving the distance ‘

d’

away from the coordinates of the measurement device in the direction of bearing ‘

b’

;

c) using the new coordinates from step b) as replacement coordinates for the new coordinates of claim 7 step e), so that the weighted average of the distances and bearings is used in subsequent measurements instead of a single distance and bearing.