Method for the acquisition and processing of geographical information of a path

• US 9,477,230 B2
• Filed: 07/22/2013
• Issued: 10/25/2016
• Est. Priority Date: 07/26/2012
• Status: Active Grant

• Current Assignee: Geonumerics, S.L.
• Original Assignee: Geonumerics, S.L.
• Inventors: Sastre I Sastre, Jaume
• Primary Examiner(s): Cheung, Calvin
• Assistant Examiner(s): SCHNEIDER, PAULA LYNN
• Application Number:
  US14/417,435
• Publication Number:
  US 20150192928A1
• Time in Patent Office: 1,191 Days
• Field of Search: 701/25
• US Class Current: 1/1
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures
• CPC Class Codes: G01C 21/04 by terrestrial means G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38
• CPC Class Codes: G05D 1/0094 involving pointing a payload, e.g. camera, weapon, sensor, towards a fixed or moving target
• CPC Class Codes: G05D 1/0808 specially adapted for aircraft

Abstract

The present invention provides a method for the simultaneous acquisition and processing of geographical information of a path acquired by tandem terrestrial and aerial missions comprising a terrestrial vehicle and an unmanned aircraft whose trajectory is slaved to the terrestrial vehicle. The method comprises: acquiring geographical data and information from the terrestrial vehicle; sending trajectory information to the aircraft from a control station hosted on the terrestrial vehicle; the aircraft determining its trajectory according to the trajectory information of the terrestrial vehicle received; acquiring geographical data and information, including images, from the aircraft; obtaining, in a processing module, the orientation of the sensors of both terrestrial vehicle and aircraft from the geographical data and information acquired; calibrating, in a processing module, the sensors of both terrestrial vehicle and aircraft from the geographical data and information acquired; and associating every image acquired with the orientation and calibration obtained.

Claims

1. A method for the acquisition and post-processing of geographical information of a path for corridor mapping, wherein the method comprises:

an initial acquisition phase comprising the steps of;

a) acquiring geographical data and information by means of a plurality of sensors of a terrestrial vehicle;

b) sending trajectory information of the terrestrial vehicle to an aircraft, from a control station hosted on the terrestrial vehicle, every certain period of time, where the time period is a design parameter;

c) when the aircraft receives the trajectory information of the terrestrial vehicle, the aircraft determines its trajectory according to the trajectory information of the terrestrial vehicle received, wherein the aircraft follows the same trajectory as the terrestrial vehicle with a temporal and spatial offset, where a time delay and a vector difference between the aircraft and the terrestrial vehicle is a design parameter that can vary with time according to the commands of an operator;

d) acquiring, simultaneously to step a), geographical data and information, including images, by means of a plurality of sensors of the aircraft;

and, after the acquisition phase, a post-processing phase comprising the steps of;

e) inputting, in a post-processing module, the geographical data and information acquired in the previous steps, which comprises images acquired by the aircraft, geographical information previously known, navigation information including time, position, velocity and attitude, coordinates of kinematic control points associated to the center of a roof target of the terrestrial vehicle, image coordinates and scale factor of the kinematic ground control points associated to said roof target of the terrestrial vehicle;

f) identifying a same ground element in different images acquired by the image sensor of the aircraft and measuring its image coordinates;

g) obtaining, in the post-processing module, the orientation of the sensors of both terrestrial vehicle and aircraft according to the inputs of step e) and step f);

h) calibrating, in the post-processing module, the sensors of both terrestrial vehicle and aircraft according to the inputs of step e) and step f); and

i) associating every image acquired with the orientation and calibration obtained in steps g) and h) respectively.

2. The method according to claim 1, wherein the kinematic ground control point associated to the terrestrial vehicle further comprises figures of known size and shape, on the roof of the terrestrial vehicle, whose ground coordinates are computed and whose image coordinates and scale factor are measured on the images acquired.

3. The method according to claim 2, wherein the obtaining the orientation and the calibrating the sensors of the aircraft further comprises using positional, attitude, size and shape information of the geometrical figures on the roof of the terrestrial vehicle.

4. The method according to claim 1, wherein kinematic ground control points associated to the terrestrial vehicle further comprise radiometric calibration targets on the roof of the terrestrial vehicle configured to be used for radiometric modelling and sensor radiometric calibration.

5. The method according to claim 1, wherein the images acquired are time-tagged.

6. The method according to claim 1, further comprising analysing the data and geographical information obtained by the plurality of sensors of the terrestrial vehicle according to error patterns and known causes of errors to identify systematic errors or the potential existence of systematic errors in a computed trajectory of the terrestrial vehicle.

7. The method according to claim 6, wherein when a possible systematic error is identified, the trajectory information acquired by the terrestrial vehicle is corrected by the geographical data and information acquired by the aircraft and by its trajectory.

8. A system for the acquisition and post-processing of geographical information of a path for corridor mapping, the system comprising:

a terrestrial vehicle equipped with a plurality of sensors configured to acquire geographical data and information;

a control station hosted on the terrestrial vehicle, the control station configured to send trajectory information of the terrestrial vehicle to an aircraft every certain period of time, where the time period is a design parameter;

an aircraft in communication with the terrestrial vehicle, wherein the aircraft is equipped with a plurality of sensors including an image sensor, and is configured to determine its trajectory according to the trajectory information received from the terrestrial vehicle, wherein the aircraft is operable to follow the same trajectory as the terrestrial vehicle with a temporal and spatial offset, where a time delay and a vector difference between the aircraft and the terrestrial vehicle is a design parameter that can vary with time according to the commands of an operator, and wherein the aircraft is configured to acquire geographical data and information, including images, simultaneously to the terrestrial vehicle by means of the plurality of sensors of the aircraft; and

a post-processing module configured for;

receiving as input the geographical data and information acquired by the respective pluralities of sensors of the terrestrial vehicle and the aircraft, which comprises geographical information previously known, navigation information including time, position, velocity and attitude, ground coordinates of the kinematic ground control points associated to a roof target of the terrestrial vehicle, and image coordinates and scale factors of the roof target;

identifying a same element in different images acquired by the image sensor of the aircraft and measuring their image coordinates and further receiving these measurements as input to the processing module;

obtaining the orientation of the sensors of both terrestrial vehicle and aircraft according to the inputs received;

calibrating the sensors of both terrestrial vehicle and aircraft according to the inputs received; and

associating every image acquired with the orientation and calibration obtained.

9. The system according to claim 8, wherein the aircraft comprises a plurality of image sensors.

10. The system according to claim 9, wherein the roof target of the terrestrial vehicle comprises geometric figures.

11. The system according to claim 10, wherein the terrestrial vehicle comprises a plurality of image sensors.