APPARATUS AND METHOD FOR FAULT-PROOF COLLECTION OF IMAGERY FOR UNDERWATER SURVEY

• US 20200132456A1
• Filed: 10/29/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: University of New Hampshire
• Original Assignee: University of New Hampshire
• Inventors: Rzhanov, Yuri
• Granted Patent: US 11,112,241 B2
• Time in Patent Office: Days
• CPC Class Codes: G01C 11/025 by scanning the object
• CPC Class Codes: G01C 13/00 Surveying specially adapted to open water, e.g. sea, lake, river or canal liquid level metering G01F
• CPC Class Codes: G01C 21/203 Specially adapted for sailing ships
• CPC Class Codes: G01C 21/3826 Terrain data
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: H04N 23/50 Constructional details
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/695 Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

An apparatus and method are presented comprising one or more sensors or cameras configured to rotate about a central motor. In some examples, the motor is configured to travel at a constant linear speed while the one or more cameras face downward and collect a set of images in a predetermined region of interest. The apparatus and method are configured for image acquisition with non-sequential image overlap. The apparatus and method are configured to eliminate gaps in image detection for fault-proof collection of imagery for an underwater survey. In some examples, long baseline (LBL) is utilized for mapping detected images to a location. In some examples, ultra-short baseline (USBL) is utilized for mapping detected images to a location. The apparatus and method are configured to utilize a simultaneous localization and mapping (SLAM) approach.

Claims

1. An apparatus for image collection, comprising:

an underwater vehicle, comprising

a central motor comprising a rotating member;

a set of arms coupled to the rotating member and extending away from the central motor; and

one or more cameras attached to a distal end of at least one arm of the set of arms, wherein the underwater vehicle is configured to travel over a predetermined region and collect a set of images of the predetermined region.

2. The apparatus of claim 1, further comprising a processor configured to create a full mosaic image using non-sequential image overlap.

3. The apparatus of claim 1, wherein at least one of the central motor, the set of arms, and the one or more cameras is provided with rounded edges to facilitate hydrodynamic motion.

4. The apparatus of claim 3, wherein the set of arms is housed within a disc.

5. The apparatus of claim 1, wherein the underwater vehicle is configured to utilize a long baseline (LBL) approach to determine positioning for each imaged location in the predetermined region.

6. The apparatus of claim 1, wherein the underwater vehicle is configured to utilize an ultra-short baseline (USBL) approach to determine positioning for each imaged location in the predetermined region.

7. An apparatus for collection of images, comprising:

an underwater vehicle comprising

a motor; and

a set of sensors configured to rotate about the motor,

wherein the underwater vehicle is configured to travel over a linear path in a predetermined region and detect information in the predetermined region.

8. The apparatus of claim 7, wherein the set of sensors are a set of time-of-flight (TOF) sensors.

9. The apparatus of claim 8, wherein the information is bathymetry information.

10. The apparatus of claim 7, wherein the set of sensors are a set of cameras.

11. The apparatus of claim 10, wherein the set of cameras are rotated at a constant rotational speed.

12. The apparatus of claim 7, wherein at least one of the set of sensors and the motor are housed within a disc.

13. A method, comprising:

driving an underwater vehicle at a constant linear speed;

rotating one or more cameras about a central motor;

capturing a set of images of a region to be mapped; and

detecting position of the underwater vehicle during image capture.

14. The method of claim 13, wherein the one or more cameras are coupled to a processor configured for image co-registration using non-sequential image overlap.

15. The method of claim 13, wherein the one or more cameras are rotated at a constant rotational speed.

16. The method of claim 13, wherein a long baseline (LBL) approach is utilized to detect position of the underwater vehicle in the region to be mapped.

17. The method of claim 13, wherein an ultra-short baseline (USBL) approach is utilized to detect position of the underwater vehicle in the region to be mapped.

18. The method of claim 13, further comprising sending the set of images to a computer.

19. The method of claim 18, further comprising performing a bundle adjustment step.

20. The method of claim 18, further comprising performing global optimization utilizing SLAM and non-sequential image overlap.

21. The method of claim 20, further comprising compiling the set of images into a map of the region.