Control system for remotely operated vehicles for operational payload employment

• US 20030212478A1
• Filed: 05/09/2002
• Published: 11/13/2003
• Est. Priority Date: 05/09/2002
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Rios, Jeffrey P.
• Granted Patent: US 6,694,228 B2
• Time in Patent Office: Days
• US Class Current: 701/2
• CPC Class Codes: G05D 1/0044 by providing the operator with a computer generated representation of the environment of the vehicle, e.g. virtual reality, maps maps used for automatic navigation G05D1/0274; flight directors G01C23/005
• CPC Class Codes: G05D 1/0094 involving pointing a payload, e.g. camera, weapon, sensor, towards a fixed or moving target

Abstract

A control system for a UAV includes control translations which maximize operational employment of the UAV payload. By determining spatial references, and then using the references to transform the control stick commands, the operator treats the UAV as a point source. For control through imagery from onboard mission sensors, the transformations provide for the UAV to move itself and achieve payload orientation.

Claims

1. A method of controlling a UAV comprising the steps of:

(1) determining a reference mode;

(2) determining a reference angle in response to said step (1);

(3) transforming a control input into a UAV command in response to said step (2).

2. A method as recited in claim 1, wherein the control input is defined by a stick_X_Cmd and a stick_Y_Cmd, and the UAV command is defined by an X command and a Y command, said step (3) defined by the relationship:

UAV_—

X_—

Cmd=(stick_—

X_—

Cmd)(Cosine[Reference_Angle])+(stick_—

Y_—

Cmd)(Sine[Reference_Angle]) UAV_—

Y_—

Cmd=(stick_—

Y_—

Cmd)(Cosine[Reference_Angle])−

(stick_—

X_—

Cmd)(Sine[Reference_Angle]).

3. A method as recited in claim 1, wherein said step (1) comprises determining between a MAP reference mode and a SENSOR reference mode.

4. A method as recited in claim 3, wherein the reference angle in the MAP reference mode of said step (2) is determined by the relationship:

Reference angle=Map orientation−

UAV heading.

5. A method as recited in claim 3, wherein the reference angle in the SENSOR reference mode of said step (2) is determined by the relationship:

Reference angle=Sensor Azimuth−

UAV heading.

6. A method as recited in claim 1, further comprising the steps of:

(a) commanding a sensor line of sight to a desired elevation angle;

(b) determining if the sensor line of sight commanded in said step (a) is within a predefined sensor operational range; and

(c) calculating the UAV command which moves the UAV to maintain the sensor line of sight commanded in said step (a) within the sensor operational range.

7. A method as recited in claim 6, wherein said step (c) comprises calculating the UAV command which moves the UAV to maintain the sensor line of sight commanded in said step (a) at the center of the sensor operational range.

8. A method as recited in claim 6, further comprising the steps of:

(d) tracking a target; and

(e) calculating the UAV command which moves the UAV to maintain the target within a sensor field of view when the target leaves the sensor operational range.

9. A method as recited in claim 1, further comprising the steps of:

(a) commanding a sensor line of sight to a desired elevation angle;

(b) confirming that the sensor line of sight commanded in said step (a) is within a predefined sensor operational range; and

(c) slewing a sensor to the sensor line of sight commanded in said step (a).

10. A method as recited in claim 9, wherein the range to where the sensor line of sight commanded in said step (a) intersects the ground is determined by the relationship:

Range=Tangent(90°

+“

sensor elevation angle”

)*UAV Altitude

Where “

sensor elevation angle”

is the elevation angle of a mission sensor from vertically straight down.

11. A method of controlling a UAV through the imagery from an onboard mission sensor comprising the steps of:

(1) selecting a point on a display;

(2) determining an angle1 line;

(3) determining an angle2; and

(4) determining a true ground distance equivalent to the display distance from the Y centerline of the display to the point with angle 1 and angle 2.

12. A method as recited in claim 11, wherein the angle1 of said step (2) is determined by the relationship:

Angle1=sensor_elevation_—

FOV*(0.5−

line Y of the point/total image line height).

13. A method as recited in claim 11, wherein the angle2 of said step (3) is determined by the relationship:

Angle2=90°

+sensor_elevation_—

FOV+Angle1

14. A method as recited in claim 11, wherein the true ground distance of said step (4) is determined by the relationship:

ground distance=UAV altitude*(tangent[Angle2]−

tangent[Angle2−

Angle1])

15. A method as recited in claim 11, further comprising the step of:

determining a true ground distance equivalent to the X display distance between the point and the X centerline of the display.

16. A method as recited in claim 15, further comprising the steps of:

(1) determining the UAV altitude;

(2) determining a number of pixels between the point and the X-centerline of the display; and

(3) determining a fixed ratio between one of the number of pixels from said step (2) and a true ground distance in relation to the UAV altitude.

17. A method as recited in claim 11, further comprising the steps of:

(a) commanding a sensor line of sight to a desired elevation angle by selecting the point on the display;

(b) determining if the sensor line of sight commanded in said step (a) is within a predefined sensor operational range; and

(c) calculating a UAV command which moves the UAV to maintain the sensor line of sight commanded in said step (a) within the sensor operational range.

18. A method as recited in claim 17, wherein said step (c) comprises calculating the UAV command which moves the UAV to maintain the point at the center of the display.

19. A method as recited in claim 11, further comprising the steps of:

(a) commanding a sensor line of sight to a desired elevation angle by selecting the point on the display;

(b) calculating a UAV command which moves the UAV to maintain the point at the center of the display.

20. A method as recited in claim 19, wherein said step (a) is commanded by a target tracking system.