Photogrammetric soil density system and method

Patent metadata

Field	Value
Publication number	US-10125464-B2
Application number	US-201615069810-A
Country	US
Kind code	B2
Filing date	Mar 14, 2016
Priority date	Mar 14, 2016
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

The present invention is an apparatus which executes a photogrammetry method for calculating soil density. After a user excavates soil, measures the mass of the excavated soil and takes multiple images of the excavation site in combination with a calibration object, a data processor uses the various values obtained from the collected images to create a point cloud data object. The processor used this point cloud data object to create a visual representation of the hole. The processor rotates and scales the visual representation. The processor also uses the point cloud data object in volumetric calculations to determine the volume of the hole. Together with the soil mass, the volume allows calculation of soil density.

First claim

What is claimed is:

1. A computer apparatus for analyzing soil density utilizing a user-selected ground plane, comprised of:
a photogrammetric data processor configured with software to perform a photogrammetry method, said photogrammetry method comprising the steps of:
receiving a variant image set of a calibration object and excavation site;
creating a point cloud from said variant image set and at least one camera data value;
instantiating a point cloud data object with point cloud data values to display a visual representation of said excavation site and said calibration object on a graphic user interface (GUI);
a first processor which receives plane coordinate values representing plane parameters and performs functions to transform said plane coordinate values to produce a volumetric cube data set which contains cube perimeter coordinate data values representing a volumetric cube, wherein one or more of said perimeter coordinate data values correspond to said plane coordinate values;
a cube grid data object having processing capability, configured to receive said volumetric cube data set and perform functions to transform said cube perimeter coordinate data values into a sub-cube data set to populate a cube grid data structure with sub-cube perimeter coordinate data values and volume values associated with each of said sub-cubes; and
a density processing component configured to receive a soil mass value M of excavated soil and said cube grid data structure and to perform functions to discard sub-cube values that are not within designated point cloud parameters and to calculate excavated volume V h and soil density value D based on remaining sub-cube values and said soil mass value M.

2. The apparatus of claim 1 , wherein said first processor is further configured with a photogrammetry processing component which is configured to receive updated plane coordinate values and re-calculate said soil density value D.

3. The apparatus of claim 1 wherein said first processor is further configured to iteratively receive updated plane coordinate values and iteratively re-calculate said soil density value D.

4. The apparatus of claim 1 , which further includes a processor for updating a plurality of pixel x-coordinate data values, a plurality of pixel y-coordinate data values and a plurality of pixel z-coordinate data values of said cloud data object using an autorotation method.

5. The apparatus of claim 4 , which further includes a processor configured to:
extract a largest pixel y-coordinate data value Y max and a smallest pixel y-coordinate data value Y min from said point cloud data object, along with a plurality of corresponding pixel z-coordinates, Z ymax and Z ymin , respectively,
update each of said plurality of pixel x-coordinate data values, said plurality of y-coordinate data values and said plurality of z-coordinate data values in said point cloud data object with an updated pixel x-coordinate data value x′ n , updated pixel y-coordinate data value y′ n and updated pixel z-coordinate data value z′ n , respectively, using the equation:

[

x
n
′

y
n
′

z
n
′

]

=

[

x
n

y
n

z
n

]

*

[

1

0

0

0

cos
⁢

⁢

θ
x

-
sin

⁢

⁢

θ
x

0

sin
⁢

⁢

θ
x

cos
⁢

⁢

θ
x

]

wherein x n is said current pixel x-coordinate data value in said point cloud data object, y n is said current pixel y-coordinate data value in said point cloud data object, z n is said current pixel z-coordinate data value in said point cloud data object, n equals said number of pixels and θ x is an x-axis angle of adjustment;
extract a largest pixel x-coordinate data value x max and a smallest pixel x-coordinate data value x min from said point cloud data object, along with a plurality of corresponding pixel z-coordinates, z xmax and z xmin , r

Assignees

• Us Army

Inventors

• Berney Iv Ernest S
• Pratt Thad C
• Ganesh Naveen B

Classifications

• G06V20/13

  Satellite images · CPC title

• G06T7/602

  Physics · mapped topic

• E02D1/025 Primary

  combined with sampling · CPC title

• G06K9/4604

  Physics · mapped topic

• G06T7/0004

  Industrial image inspection · CPC title