Navigation device

• US 20100268454A1
• Filed: 04/20/2010
• Published: 10/21/2010
• Est. Priority Date: 04/20/2009
• Status: Active Grant

• Current Assignee: J & M Inertial Navigation Limited
• Original Assignee: J & M Inertial Navigation Limited
• Inventors: Fountain, Jonathan William
• Granted Patent: US 8,718,936 B2
• Time in Patent Office: Days
• US Class Current: 701/201
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 21/34 Route searching; Route guidance

Abstract

Apparatus for, and a method of, providing output data to a person identifying a route back to a recorded waypoint position. Personal navigation apparatus for providing output data to a person identifying a route back to a recorded waypoint position, comprising a route indication device including a visual display element; and a positioning device. The positioning system includes a processing system having a data storage device, a first micromechanical device configured to produce an output signal proportional to an acceleration along an axis, and a second micromechanical device having components in constant motion and configured to produce an output signal proportional to its angular rate of motion around an axis. The processing system is configured to generate and store in said data storage device position data describing the position of said personal navigation apparatus within a reference space, based upon data received from said first micromechanical device and said second micromechanical device.

Claims

1. Personal navigation apparatus for providing output data to a person identifying a route back to a recorded waypoint position, comprising:

a route indication device including a visual display element; and

a positioning device, including;

a processing system having a data storage device,

a first micromechanical device configured to produce an output signal proportional to an acceleration along an axis, and

a second micromechanical device having components in constant motion and configured to produce an output signal proportional to its angular rate of motion around an axis;

wherein said processing system is configured to generate and store in said data storage device position data describing the position of said personal navigation apparatus within a reference space, based upon data received from said first micromechanical device and said second micromechanical device.

2. The personal navigation apparatus of claim 1, wherein said first micromechanical device is a linear accelerometer.

3. The personal navigation apparatus of claim 2, wherein said linear accelerometer includes a proof mass configured to be displaced from an equilibrium position under a linear acceleration.

4. The personal navigation apparatus of claim 1, wherein said second micromechanical device is a vibrating structure gyroscope.

5. The personal navigation apparatus of claim 4, wherein said vibrating structure gyroscope outputs a signal proportional to its angular rate of motion around an axis by measuring a Coriolis acceleration.

6. The personal navigation apparatus of claim 1, wherein said recorded waypoint position is defined on activation of a recorded waypoint position routine in said processor.

7. The personal navigation apparatus of claim 1, wherein said route indication device includes a manually operable device configured to allow activation of said recorded waypoint position routine.

8. The personal navigation apparatus of claim 1, wherein said visual display element is configured to display said route back to said recorded waypoint position on activation of a route display routine in said processor.

9. The personal navigation apparatus of claim 1, wherein said route indication device includes a manually operable device configured to allow activation of said route display routine.

10. The personal navigation apparatus of claim 1, wherein said route indication device and said position device each further comprise a communication interface configured to exchange data and instructions between said route indication device and said position device.

11. The personal navigation apparatus of claim 10, wherein said communication interface is a wireless communication interface.

12. The personal navigation apparatus of claim 1, wherein said apparatus is submersible in water.

13. The personal navigation apparatus of claim 1, wherein said visual display element includes a touch screen.

14. The personal navigation apparatus of claim 12, further comprising a depth sensor.

15. A method of providing output data to a person identifying a route back to a recorded waypoint position, comprising the steps of:

generating position data describing the position of said personal navigation apparatus within a reference space, based upon data received from a first micromechanical device and a second micromechanical device,

storing, in a data storage device, generated position data,

identifying a recorded waypoint position,

identifying an event position, said event position being a relative position relative to a stored position, and

generating route data relating to a route from said event position to a stored position; and

visually indicating, on a route indication device, a route, based on said route data, identifying a route back to said recorded waypoint position.

16. The method of claim 15, wherein said generated position data is stored in chronological order.

17. The method of claim 15, wherein identifying a recorded waypoint position comprises selecting the last stored recorded waypoint position.

18. The method of claim 15, further comprising the step of transmitting said generated route data from said data storage device to said route indication device via a communication interface.

19. The method of claim 15, wherein the step of visually indicating a route further comprises displaying an arrow on said route indication device identifying the direction in which a person must travel.

20. The method of claim 15, wherein the step of visually indicating a route further comprises displaying a distance to be travelled back to a recorded waypoint position.