Range measurement device

• US 8,582,086 B2
• Filed: 11/09/2010
• Issued: 11/12/2013
• Est. Priority Date: 08/13/2007
• Status: Expired due to Fees

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Hartman, Randolph G., Elgersma, Michael R.
• Primary Examiner(s): RATCLIFFE, LUKE D
• Application Number:
  US12/942,689
• Publication Number:
  US 20110051120A1
• Time in Patent Office: 1,099 Days
• Field of Search: 356 301- 315, 356 401- 41, 356 501- 515, 356 6- 22, 356/28, 356/28.5, 35613901-1391
• US Class Current: 356/5.01
• CPC Class Codes: G01S 17/10 using transmission of interrupted, pulse-modulated waves determination of distance by phase measurements G01S17/32
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/66 Tracking systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/86 Combinations of lidar systems with systems other than lidar, radar or sonar, e.g. with direction finders
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 7/4808 Evaluating distance, position or velocity data
• CPC Class Codes: G01S 7/4814 of transmitters alone
• CPC Class Codes: G01S 7/4816 of receivers alone

Abstract

A range measurement device is disclosed. The device comprises a flash laser radar configured to produce a first laser pulse at a first time. The device receives, at a second time, reflections of the first laser pulse from at least one object within a 360 degree field of view. The device further comprises a timing electronics module, an image sensor in communication with the timing electronics module, a mirror element coupled between the image sensor and the laser radar, and a lens. The mirror element includes a first reflector configured to disperse the reflections of the first laser pulse within at least a portion of the 360 degree field of view and a second reflector configured to collect returning reflections of the first laser pulse from the at least one object into the image sensor. The lens is configured to focus the returning reflections onto the image sensor.

Claims

1. A navigation system, comprising:

a range measurement device operable to provide at least one of angles, ranges, and attitude data of at least one object, the range measurement device including;

a flash laser radar operable to produce a first laser pulse at a first time;

an image sensor configured to receive, at a second time, reflections of the first laser pulse from the at least one object within a 360 degree field of view of the range measurement device; and

a mirror element located between the image sensor and the flash laser radar, the minor element including a first reflector surface configured to disperse reflections of the first laser pulse into a 360 degree field of view, and a second reflector surface configured to collect returning reflections of the first laser pulse from the at least one object within the 360 degree field of view into the image sensor; and

a processor in communication with the range measurement device, the processor configured to;

track a range and an attitude based on an output of the range measurement device to the at least one object within a localized time period between the first and second times based on the reflections received from the at least one object;

and

as additional reflections are received from the at least one object, record additional time periods to determine at least one of a current position and a current attitude of the range measurement device relative to the at least one object.

2. The system of claim 1, further comprising at least one of an inertial sensor, a heading sensor, a speed sensor, a global positioning sensor, and an altimeter sensor in communication with the processor.

3. The system of claim 1, wherein the processor further comprises program instructions to determine at least one of an absolute position and an absolute attitude of the system based on the measurements to the at least one object with prior information including at least one known attitude and position.

4. The system of claim 1, wherein the processor further comprises program instructions to determine at least one of a range measurement to the at least one object, an azimuth measurement to the at least one object, and a location measurement of the at least one object.

5. A method for measuring range to determine position, the method comprising:

producing a first laser pulse with a laser radar of a range measurement device, the range measurement device comprising a minor element and an image sensor, the mirror element including a first reflecting surface and a second reflecting surface;

dispersing reflections of the first laser pulse from the first reflecting surface at a first time into a 360 degree field of view;

receiving reflections of the first laser pulse from at least one object within the 360 degree field of view from the second reflecting surface at the image sensor at a second time;

based on the reflections received at the second time, tracking at least one of a range and an attitude from a host vehicle having the laser radar to the at least one object within a localized time period between the first and second times; and

as additional laser pulse reflections are received, recording additional localized time periods to determine at least one of a current position and a current attitude of the host vehicle relative to the at least one object.

6. The method of claim 5, further comprising determining at least one of an absolute position and an absolute attitude of the host vehicle based on the reflections received and a known location of the at least one object.

7. The method of claim 5, further comprising:

synchronizing a range image of the at least one reflection of the first laser pulse with the laser radar at the second time; and

determining a relative velocity between the range measurement device and the at least one object based on a localized time period between the first and second times.

8. The method of claim 7, wherein synchronizing the range image comprises determining at least one of a range measurement to the at least one object, an azimuth measurement to the at least one object, and a location measurement of the at least one object.

9. The method of claim 5, further comprising determining a relative range between the range measurement device and the at least one object.

10. The method of claim 5, wherein receiving the reflections further comprises determining a relative angle between the at least one object and the host vehicle based on relative transit times.

11. The method of claim 5, wherein tracking further comprises:

determining at least one of a relative position and relative attitude of the at least one object within the 360 degree field of view; and

determining at least one of an absolute position and absolute attitude of the at least one object when an absolute position of the laser radar is known.

12. The method of claim 5, wherein tracking further comprises:

determining a relative position angle between the at least one object and the host vehicle, wherein the at least one object is a targeted object;

determining at least a relative position and relative attitude to the targeted object; and

determining at least one of an absolute position and absolute attitude of the targeted object when an absolute position of the laser radar is known.

13. The method of claim 5, wherein recording the additional localized time periods comprises at least one of:

measuring the additional laser pulse reflections to determine a current heading, pitch, and roll of the host vehicle; and

measuring the additional laser pulse reflections to determine a location of a targeted object relative to the host vehicle.

14. A method for measuring range to determine position, the method comprising:

dispersing a first laser pulse from a host vehicle at a first time into a 360 degree field of view;

receiving reflections of the first laser pulse from a plurality of objects within the 360 degree field of view at a second time;

based on the reflections received at the second time, tracking a range and an attitude from the host vehicle to the objects within a localized time period between the first and second times; and

as additional laser pulse reflections are received, recording additional localized time periods to determine a current position and a current attitude of the host vehicle relative to the objects.

15. The method of claim 14, further comprising determining an absolute position and an absolute attitude of the host vehicle based on the reflections received and a known location of the objects.

16. The method of claim 14, further comprising determining a relative range between the host vehicle and the objects.

17. The method of claim 14, wherein receiving the reflections further comprises determining a relative angle between the objects and the host vehicle based on relative transit times.

18. The method of claim 14, wherein tracking further comprises:

determining a relative position and relative attitude of the objects within the 360 degree field of view; and

determining an absolute position and absolute attitude of the objects when an absolute position of the host vehicle is known.

19. The method of claim 14, wherein tracking further comprises:

determining a relative position angle between the objects and the host vehicle, wherein the objects are targeted objects;

determining a relative position and relative attitude to the targeted objects; and

determining an absolute position and absolute attitude of the targeted objects when an absolute position of the host vehicle is known.

20. The method of claim 14, wherein recording the additional localized time periods comprises at least one of:

measuring the additional laser pulse reflections to determine a current heading, pitch, and roll of the host vehicle; and

measuring the additional laser pulse reflections to determine a location of the objects relative to the host vehicle.