Self-leveling laser horizon for navigation guidance

• US 20060080004A1
• Filed: 04/29/2005
• Published: 04/13/2006
• Est. Priority Date: 04/29/2004
• Status: Active Grant

• Current Assignee: Munro & Associates, Inc.
• Original Assignee: JADI, Inc.
• Inventors: Cheok, Ka C., Smid, G. Edzko
• Granted Patent: US 7,908,041 B2
• Time in Patent Office: Days
• US Class Current: 701/1
• CPC Class Codes: G01C 15/14 Artificial horizons
• CPC Class Codes: G01C 23/005 Flight directors indicating arrangements specially adapted for rotary gyroscopes G01C19/32

Abstract

The present invention includes an artificial horizon device including a sensor unit with a movable platform, at least one actuator linked to the platform, and one or more sensors located on the platform for sensing the position orientation of the platform relative to an external mass or the motion of the platform. The horizon device also includes a processing unit signally connected to the sensors and the at least one actuator. The processing unit is adapted to receive signals from the sensors and send signals to the actuators to move the platform to a horizontal orientation. The horizon device also includes either a display unit comprising an indicator of a horizon line which substantially corresponds to the horizontal orientation of the platform or a secondary device.

Claims

1. An artificial horizon device for use in a vehicle, comprising:

a sensor unit comprising;

a movable platform;

at least one actuator linked to the platform; and

one or more sensors located on the platform for sensing the orientation of the platform relative to an external mass or the motion of the platform; and

a processing unit is signally connected to the sensors and the at least one actuator and adapted to at least receive signals from the sensors and to at least send signals to the actuators to move the platform to a horizontal orientation; and

either a display unit comprising an indicator of a horizon line which substantially corresponds to the horizontal orientation of the platform or a secondary device.

2. The device of claim 1 wherein the display unit is located on the platform.

3. The device of claim 1 wherein the sensor unit, processing unit and display unit are located in a single housing.

4. The device of claim 3 wherein the single housing is portable.

5. The device of claim 1 wherein the indicator is a visual, an auditory, a tactile indicator, or combinations thereof.

6. The device of claim 5 wherein the indicator is a visual indicator displayed in at least the operator'"'"'s peripheral field of vision.

7. The device of claim 6 wherein the indicator is a visual indicator and comprises a light line.

8. The device of claim 6 wherein the indicator is a visual indicator and comprises one or more light bars.

9. The device of claim 1 wherein the secondary device is selected from a navigation system, a device on the control panel or dashboard, a third party display system, an autopilot system, a tracking system, a redundant horizon device, a warning system, a data logging devices, a telemetry device, an autonomous vehicle, multiples thereof and combinations thereof.

10. The device of claim 1 wherein the one or more sensors of the sensor unit comprises:

at least a dual-axis accelerometer located in a plane near the plane of the platform; and

at least a pair of gyroscopes, each located on an axis of rotation for the platform, where the axes of rotation are perpendicular to each other.

11. The device of claim 10 further comprising at least a third gyroscope located on a third axis of rotation that is orthogonal to the other axes of rotation for measuring yaw rate.

12. A method displaying an artificial horizon, comprising:

measuring a platform orientation relative to an external mass; and

adjusting the platform orientation relative to the external mass to achieve a horizontal orientation of the platform.

13. The method of claim 12 wherein the measuring step comprises measuring an angle theta between an orientation axis and the gravity vector and wherein the adjusting step comprises moving the platform to minimize the angle theta.

14. The method of claim 12 wherein the measuring step comprises comparing the platform orientation at a first time to the platform orientation at a second time and the adjusting step comprises moving the platform to partially or wholly eliminate any deviation between the platform orientations.

15. The method of claim 12 measuring step comprises compensating for errors in the orientation of the platform.

16. The method of claim 15 wherein the compensating step comprises calculating a compensation factor that represents the difference between true gravity and observed gravity.

17. The method of claim 12 further comprising displaying a humanly perceptible indicator of a horizon.

18. The method of claim 17 wherein the displaying step comprises displaying a light line.

19. The method of claim 17 wherein the displaying step comprises displaying one or more lights on a plurality of light bars.

20. The method of claim 12 wherein the platform has unbounded ranges of motion.