Systems and associated methods for producing a 3D sonar image

Patent metadata

Field	Value
Publication number	US-10018719-B2
Application number	US-201514683578-A
Country	US
Kind code	B2
Filing date	Apr 10, 2015
Priority date	Mar 5, 2015
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

Provided are a sonar system and transducer assembly for producing a 3D image of an underwater environment. The sonar system may include a housing having a transmit transducer that may transmit sonar pulses into the water. The system may include at least one transducer array in the housing that receives first, second, and third sonar returns with first, second, and third transducer elements and converts the first, second, and third returns into first, second, and third sonar return data. A sonar signal processor may then generate a first and second set of 2D sonar data based on the sonar return data, generate a third set of 2D sonar data based on a correlation of the first and second set of 2D sonar data, and generate a 3D mesh data based on the third set of 2D sonar data. An associated method of using the sonar system is also provided.

First claim

The invention claimed is:

1. A sonar system comprising:
a housing mountable to a watercraft capable of traversing a body of water;
a transmit transducer element positioned within the housing and configured to transmit sonar pulses into the water;
at least one transducer array positioned within the housing and aimed at least downwardly from the watercraft,
wherein the transducer array comprises a first transducer element, a second transducer element, and a third transducer element,
wherein the first transducer element is configured to receive first sonar returns from the sonar pulses produced by the transmit transducer element and convert sound energy of the first sonar returns into first sonar return data,
wherein the second transducer element is configured to receive second sonar returns from the sonar pulses produced by the transmit transducer element and convert sound energy of the second sonar returns into second sonar return data,
wherein the third transducer element is configured to receive third sonar returns from the sonar pulses produced by the transmit transducer element and convert sound energy of the third sonar returns into third sonar return data, and
wherein the first transducer element is positioned within the housing at a first predetermined distance from the second transducer element, and wherein the first transducer element is positioned within the housing at a second predetermined distance from the third transducer element; and

a sonar signal processor configured to:
process the first sonar return data and the second sonar return data to generate a first set of 2D sonar data, wherein each sonar return of the first set of 2D sonar data defines a first distance value and a first angle, wherein the first angle associated with each sonar return of the first set of 2D sonar data is based on the first predetermined distance between the first transducer element and the second transducer element, wherein the first distance value associated with each sonar return of the first set of 2D sonar data corresponds to a first distance between a position of the sonar return and the at least one transducer array;
process the first sonar return data and the third sonar return data to generate a second set of 2D sonar data, wherein each sonar return of the second set of 2D sonar data defines a second distance value and a second angle, wherein the second angle associated with each sonar return of the second set of 2D sonar data is based on the second predetermined distance between the first transducer element and the third transducer element, wherein the second distance value associated with each sonar return of the second set of 2D sonar data corresponds to a second distance between the position of the sonar return and the at least one transducer array;
generate a third set of 2D sonar data based on at least a correlation of the first set of 2D sonar data and the second set of 2D sonar data; and
generate 3D mesh data based on at least the third set of 2D sonar data, wherein the 3D mesh data is a basis for a 3D image of an underwater environment in a three dimensional coordinate system.

2. The sonar system of claim 1 , further comprising a display configured to display a 3D image of an underwater environment based at least on the 3D mesh data.

3. The sonar system of claim 1 , wherein the sonar signal processor is further configured to:
generate a plurality of third sets of 2D sonar data as the watercraft traverses the body of water; and
generate the 3D mesh data based on the plurality of third sets of 2D sonar data generated as the watercraft traverses the body of water.

4. The sonar system of claim 1 , wherein each sonar return of the first set of 2D sonar data further defines a first signal return strength value, and wherein each sonar return of the second set of 2D sonar data further defines a second signal return strength value.

5. The sonar system of claim 1 , wherein the first predetermined distance between the first transducer element and the second transducer element is different than a third predetermined distance between the second transducer element and the third transducer element.

6. The sonar system of claim 1 , wherein the first predetermined distance is designed during manufacture based on a frequency of operation of the first transducer element and the second transducer element, and wherein the second predetermined distance is designed based on a frequency of operation of the first transducer element and the third transducer element.

7. The sonar system of claim 1 , wherein the sonar signal processor is configured to generate the third set of 2D sonar data by:
correlating at least one sonar return from the first set of 2D sonar data with at least one sonar return from the second set of 2D sonar data; and
generating at least one sonar return for the third set of 2D sonar data based on the correlation between the at least one sonar return from the first set of 2D sonar data and the at least one sonar return from the second set of 2D sonar data.

8. The sonar system of claim 7 , wherein the sonar signal processor is configured to generate the at least one sonar return for the third set of 2D sonar data by averaging at least one attribute of the at least one sonar return from the first set of 2D sonar data with at least one attribute of the at least one sonar return from the second set of 2D sonar data.

9. The sonar system of claim 8 , wherein the at least one attribute comprises an angle associated with each sonar return.

10. The sonar system of claim 1 , wherein the third transducer element is positioned a third predetermined distance away from the second transducer element, and wherein the sonar signal processor is configured to:
process the second sonar return data and the third sonar return data to generate a fourth set of 2D sonar data based on at least the third predetermined distance between the second transducer element and the third transducer element; and
generate the third set of 2D sonar data based on at least a correlation of the first set of 2D sonar data, the second set of 2D sonar data, and the fourth set of 2D sonar data.

11. The sonar system of claim 1 , wherein the transducer array comprises a fourth transducer element electrically connected in parallel to the third transducer element such that the third transducer element and the fourth transducer element are configured to receive the third sonar returns together from the sonar pulses produced by the transmit transducer element and convert the sound energy of the third sonar returns into the third sonar return data.

12. The sonar system of claim 1 , wherein the transmit transducer element defines a linear downscan transducer element that is configured to transmit the sonar pulses in the form of a fan-shaped beam in at least a direction substantially perpendicular to a plane corresponding to a surface of the body of water.

13. The sonar system of claim 12 , wherein the linear downscan transducer element is forming of a plurality of transducer elements electrically connected to act as the linear downscan transducer element.

14. The sonar system of claim 1 , wherein the first transducer element is formed of a plurality of transducer elements electrically connected to act as the first transducer element.

15. A transducer assembly comprising:
a housing mountable to a watercraft capable of traversing a body of water;
a transmit transducer element positioned within the housing and configured to transmit sonar pulses into the water;
at least one transducer array positioned within the housing and aimed at least downwardly from

Assignees

• Navico Holding As

Inventors

• Proctor Alan Lee
• Parks David Austin
• Horner Ronald Joe

Classifications

• G01S15/89

  for mapping or imaging · CPC title

• G01S7/521

  Constructional features · CPC title

• G01S15/003

  Bistatic sonar systems; Multistatic sonar systems · CPC title

• G01S7/56

  Display arrangements {(short-range imaging G01S7/52053)} · CPC title

• G01S15/8902 Primary

  Side-looking sonar · CPC title