Computer instructions for positioning a wire using sensor information

• US 8,332,174 B1
• Filed: 05/23/2012
• Issued: 12/11/2012
• Est. Priority Date: 05/23/2011
• Status: Expired due to Fees

• Current Assignee: NCS Subsea, Inc. (Ocean Floor Geophysics, Inc.)
• Original Assignee: NCS Subsea, Inc. (Ocean Floor Geophysics, Inc.)
• Inventors: Majzlik, Edward, Hise, Alfred L., Hardy, Brian, Zinn, Noel
• Primary Examiner(s): Charioui, Mohamed
• Assistant Examiner(s): Lee, Paul D
• Application Number:
  US13/479,027
• Time in Patent Office: 202 Days
• Field of Search: 702/94, 702/95, 702/150, 702/151
• US Class Current: 702/95
• CPC Class Codes: G01C 13/00 Surveying specially adapted to open water, e.g. sea, lake, river or canal liquid level metering G01F

Abstract

Computer instructions for determining coordinates for nodes on a wire secured to tow lines of a floating vessel for analyzing geological formations is provided. The computer instructions can use sensors in communication with a processor to determine the coordinates of nodes and provide azimuths tangential to the wire. A library of nominal values for polynomial coefficients, a library of known distances along the wire, and a library of preset limits can be stored in a data storage. The computer instructions can: receive sensor information, compute bearing, reorient the coordinates, rotate the azimuth, construct a polynomial algorithm, compute the azimuth, form a residual, compute updated differences until the residual is within preset limits, calculate local coordinates for nodes, and rotate the local coordinates from the local coordinate system to the projected coordinate system.

Claims

1. Computer instructions on a non-transitory computer readable medium for determining projected coordinates in a projected coordinate system for at least one node on a wire having a plurality of nodes, wherein the wire is secured to two separated tow lines, wherein each tow line has a diverter, and wherein the two separated tow lines are secured to a floating vessel, the computer instructions comprising:

a. computer instructions to form a library of nominal values for third, fourth, or fifth order polynomial coefficients;

b. computer instructions to form a library of known distances along the wire comprising;

(i) distances to first in-water sensors;

(ii) distances to second in-water sensors;

(iii) distances to each node of the plurality of nodes;

(iv) distances to locations along the wire;

or

(v) combinations thereof;

c. computer instructions to form a library of preset limits comprising preset limits;

d. computer instructions to receive sensor information from the first in-water sensors and the second in-water sensors;

e. computer instructions to;

(i) use projected coordinates from the first in-water sensors to compute a bearing between the first in-water sensors; and

(ii) use the bearing with the sensor information and a first rotation algorithm to reorient the projected coordinates of all of the first in-water sensors to local x-y coordinates, forming a local x-y coordinate system;

f. computer instructions to rotate azimuths tangential to the wire from the second in-water sensors using the bearing and a second rotation algorithm, thereby reorienting all azimuths tangential to the wire into the local x-y coordinate system;

g. computer instructions to construct a third, fourth, or fifth order polynomial algorithm of the wire in using;

(i) nominal values from the library of nominal values for third order polynomial coefficients;

(ii) the local x-y coordinates of the first in-water sensors; and

(iii) at least one distance along the wire from the library of known distances along the wire;

h. computer instructions to compute an azimuth tangential to the wire at each second in-water sensor using the third, fourth, or fifth order polynomial algorithm;

i. computer instructions to compute a difference between the computed azimuth tangential to the wire and the reoriented azimuths tangential to the wire to form a residual;

j. computer instructions to use the residual with a least squares technique to update the library of nominal values for third, fourth, or fifth order polynomial coefficients;

k. computer instructions to construct an updated third, fourth, or fifth order polynomial algorithm of the wire using;

(i) updated nominal values from the updated library of nominal values for third, fourth, or fifth order polynomial coefficients;

(ii) the local x-y coordinates of the first in-water sensors; and

(iii) at least one distance along the wire from the library of known distances along the wire;

l. computer instructions to compute an updated azimuth tangential to the wire at each second in-water sensor;

m. computer instructions to compute an updated difference between the computed updated azimuth tangential to the wire with the reoriented azimuths tangential to the wire until the residual is within one of the preset limits from the library of preset limits;

n. computer instructions to calculate a pair of local x-y coordinates for at least one of the plurality of nodes on the wire; and

o. computer instructions to use the bearing and a third rotation algorithm to rotate the pair of local x-y coordinates for at least one of the plurality of nodes on the wire from the local x-y coordinate system to the projected coordinate system.

2. The computer instructions of claim 1, wherein the non-transitory computer readable medium is a data storage in communication with a processor, wherein each computer instruction is configured to instruct the processor, and wherein the processor is configured to execute each computer instruction.

3. The computer instructions of claim 2, wherein the data storage is configured to receive the sensor information from:

a. at least a pair of first in-water sensors are deployed to determine the projected coordinates for a position on the wire, wherein each first in-water sensor is;

(i) embedded in the wire;

(ii) positioned adjacent one of the plurality of nodes on the wire;

(iii) proximate to the wire;

(iv) on a buoy towed from the wire;

or

(v) combinations thereof; and

b. at least a pair of second in-water sensors are deployed to provide azimuths tangential to the wire, wherein each second in-water sensor is;

(i) embedded in the wire;

(ii) attached to the wire;

or

(iii) combinations thereof.

4. The computer instructions of claim 3, wherein the data storage is further configured to receive the sensor information from a third in-water sensor on:

each of the plurality of nodes, each of the first in-water sensors, and each of the second in-water sensors, wherein;

a. each third in-water sensor is in communication with the processor; and

b. each third in-water sensor is a depth sensor that transmits a water depth for each of the plurality of nodes, each of the first in-water sensors, and each of the second in-water sensors.

5. The computer instructions of claim 4, further comprising computer instructions to use the water depths for each of the plurality of nodes to modify the library of known distances along the wire.

6. The computer instructions of claim 3, wherein the computer instructions use the pair of first in-water sensors to determine the position on the wire, and wherein each first in-water sensor is:

a. a global positioning system sensor;

b. a laser sensor;

c. an acoustic sensor;

or

d. combinations thereof.

7. The computer instructions of claim 2, wherein a network is in communication with the processor.

8. The computer instructions of claim 2, further comprising:

a. computer instructions to instruct the processor to process in real-time as the floating vessel traverses over a near surface geological formation;

b. computer instructions to instruct the processor to process after the floating vessel has acquired all of the sensor information from all of the first in-water sensors and all of the second in-water sensors;

or

c. combinations thereof.

9. The computer instructions of claim 1, wherein the two separated tow lines are wire rope, electrical wire, cable, polymer rope, hemp rope, or combinations thereof.

10. The computer instructions of claim 1, further comprising computer instructions to construct a real-time display of the wire.

11. The computer instructions of claim 10, wherein the real-time display further comprises:

a depth profile of the wire and streamers on the wire, separations between nodes of the plurality of nodes, compass data, depth data, the polynomial coefficients, event information, or combinations thereof.

12. The computer instructions of claim 10, wherein:

a. at least one streamer is attached to the wire, and wherein each streamer is connected to at least one of the plurality of nodes for collecting seismic data of a near surface geological formation;

or

b. at least one hydrophone is attached to the wire, and wherein each hydrophone is connected to at least one of the plurality of nodes for collecting seismic data of the near surface geological formation.

13. The computer instructions of claim 12, further comprising computer instructions to identify a location of the at least one streamer or the at least one hydrophone in real-time using the real-time display.

14. The computer instructions of claim 13, further comprising computer instructions to transmit an alarm to the real-time display or over the network when the location of any of the streamers or the hydrophones moves outside of one of the preset limits in the library of preset limits.

15. The computer instructions of claim 1, further comprising computer instructions to create a trend analysis over time using the third, fourth, or fifth order polynomial algorithm, wherein the trend analysis over time is a plot of distances between nodes of the plurality of nodes versus time.

16. The computer instructions of claim 1, further comprising computer instructions to create a trend analysis event-by-event using the third, fourth, or fifth order polynomial algorithm, wherein the trend analysis event-by-event is a plot of distances between nodes of the plurality of nodes versus events.

17. The computer instructions of claim 1, further comprising computer instructions to create a log file containing the local x-y coordinates, the projected coordinates of the projected coordinate system, events, time stamps, or combinations thereof.

18. The computer instructions of claim 1, wherein the sensor information comprises a time stamp.

19. The computer instructions of claim 1, wherein the sensor information comprises:

a. azimuths tangential to the wire;

b. the projected coordinates for the position on the wire;

or

c. combinations thereof.