Method of autonomous power line detection, avoidance, navigation, and inspection using aerial crafts

Patent metadata

Field	Value
Publication number	US-9964658-B2
Application number	US-201514875927-A
Country	US
Kind code	B2
Filing date	Oct 6, 2015
Priority date	Oct 6, 2015
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

Embodiments of the present invention relate to power line detection, and more particularly, to methods and systems for autonomous power line detection, avoidance, navigation, and inspection. They may be implemented using aerial crafts, but do not have to. According to an embodiment, a method for detecting energized power lines in ambient space in the vicinity of an aerial craft is presented. The method includes measuring, with sensors located on the aerial craft, electric and magnetic fields in the space; and with a power line detection controller, detecting an energized power line in the space in the vicinity of the aerial craft using the sensor data; and determining the orientation of the detected energized power line in the space based on the electric and magnetic field measurements. Similar methods and systems are also presented.

First claim

The invention claimed is:

1. A method for detecting energized power lines in ambient space in the vicinity of an aerial craft, the method comprising:
measuring, with sensors located on the aerial craft, electric and magnetic fields in said space; and
with a power line detection controller,
detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data;
determining the direction of power flow through the energized power line using a Poynting vector, wherein the Poynting vector points parallel to the energized power line; and
associating, as a directional reference, the Poynting vector for the orientation of the detected energized power line in said space.

2. The method of claim 1 , wherein detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data comprising:
(a) using a derivative of the electric field measurement;
(b) using a derivative of the magnetic field measurement; and/or
(c) using normalized values of the electric field measurement and/or the magnetic field measurement.

3. The method of claim 2 , wherein detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data comprises:
(d) using derivatives of both the electric and magnetic field measurements; and/or
(e) using normalized derivatives of both the electric and/or magnetic field measurements.

4. The method of claim 1 , wherein detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data comprises:
(f) using a Poynting vector;
(g) using a derivative of the Poynting vector; and/or
(h) using a normalized derivative of the Poynting vector.

5. The method of claim 1 , wherein detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data further comprises: identifying any power lines in said space based on a determination that the electric field measurement, the magnetic field measurement, a derivative of the electric field measurement, a derivative of the magnetic field measurement, a normalized derivative of the electric field measurement, a normalized derivative of the magnetic field measurement, a Poynting vector, a derivative of the Poynting vector, and/or a normalized derivative of the Poynting vector is/are greater than a corresponding predetermined threshold value for that value.

6. The method of claim 1 , further comprises: calculating the Poynting vector using the measured electric and magnetic fields.

7. The method of claim 6 , wherein the Poynting vector is calculated every power cycle of the electricity expected to be carried by the power line.

8. The method of claim 1 , further comprising: tracking, in said space, the locations of the aerial craft and the associated directional reference for any detected energized power line.

9. The method of claim 1 , further comprising: alerting a human pilot to the presence of any detected energized power line in the vicinity of the aerial craft.

10. The method of claim 1 , further comprising: automatically controlling the aerial craft to avoid colliding with the energized power line taking into account the associated directional reference for the power line.

11. The method of claim 1 , further comprising: controlling the aerial craft to follow along in a direction substantially parallel to the associated directional reference for the detected energized power line.

12. The method of claim 1 , wherein detecting an energized power line in said space in the vicinity of the aerial craft using the sensor data comprises:
using a derivative of the Poynting vector.

13. A system for detecting energized power lines in ambient space in the vicinity of an aerial craft, the system comprising:
electric field and magnetic field sensors located on the aerial craft configured to measure the electric and magnetic fields in said space; and
a power line detection controller configured to:
detect an energized power line in said space in the vicinity of the aerial craft using the sensor data;
determine the direction of power flow through the energized power line using a Poynting vector, wherein the Poynting vector points parallel to the energized power line; and
associate, as a directional reference, the Poynting vector for the orientation of the detected energized power line in said space.

14. The system of claim 13 , wherein the electric field sensor and magnetic field sensor each comprise a single three-axis sensor or three single-axis sensors aligned orthogonally.

15. The system of claim 13 , wherein the electric field sensor and magnetic field sensor are located at the same position on the aerial craft.

16. The system of claim 13 , wherein there is a pair of electric field and magnetic field sensors, and the controller is further configured to take derivative measurements from said sensors.

17. The system of claim 13 , further comprising: an instrument panel having audio means, visual means, or both, for alerting a pilot to a detected energized power line; and means for displaying the location and/or orientation of the power lines to the pilot.

18. The system of claim 13 , further comprising a dynamic flight controller, wherein the power line detection controller is further configured to determining maneuvers for the aerial craft to avoid the detected energized power lines which are provided to the dynamic flight controller taking into account the associated directional reference for the power line.

19. The system of claim 18 , wherein the power line detection controller is further configured to determine maneuvers for the aerial craft to inspect the detected energized power lines taking into account the associated directional reference for the power line.

20. The system of claim 13 , wherein the power line detection controller is located on the aerial craft.

21. An aerial craft configured to detect energized power lines in ambient space comprising:
electric field and magnetic field sensors configured to measure the electric and magnetic fields in said space in the vicinity of the aerial craft; and
a power line detection controller configured to:
detect an energized power line in said space in the vicinity of the aerial craft using the sensor data;
determine the direction of power flow through the energized power line using a Poynting vector, wherein the Poynting vector points parallel to the energized power line; and
associate, as a directional reference, the Poynting vector for the orientation of the detected energized power line in said space.

22. A device configured to detect energized power lines comprising:
electric field and magnetic field sensors configured to measure the electric and magnetic fields in said space; and
a controller configured to: detect an energized power line in said space using the sensor data,
wherein, in detecting an energized power line in said space in the vicinity of device using the sensor data, the controller is configured to:
(a) use a derivative of the electric field measurement;
(b) use a derivative of the magnetic field measurement;
(c) use a normalized derivative of the electric field measurement;
(d) use a normalized derivative of the magnetic field measurement;
(e) use a derivative of the Poynting vector; and/or
(f) use a normalized derivative of the Poynting vector.

23. The device of claim 22 , wherein the device is hand-held or incorporated into a helmet or veh

Assignees

• U S Army Res Laboratory Attn Rdrl Loc I
• Us Army

Inventors

• Hull David M
• Adelman Ross N

Classifications

• B64U2201/00

  UAVs characterised by their flight controls · CPC title

• G05D1/0094

  involving pointing a payload, e.g. camera, weapon, sensor, towards a fixed or moving target · CPC title

• G01S1/00

  Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith (position fixing by co-ordinating a plurality of determinations of direction or position lines G01S5/00) · CPC title

• G01V3/08 Primary

  operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices (with electromagnetic waves G01V3/12) · CPC title

• B64C13/18

  using automatic pilot · CPC title