Traffic scanning LIDAR

• US 8,629,977 B2
• Filed: 04/13/2011
• Issued: 01/14/2014
• Est. Priority Date: 04/14/2010
• Status: Active Grant

• Current Assignee: Digital Ally Incorporated
• Original Assignee: Digital Ally Incorporated
• Inventors: Phillips, Steven L., Oguz, Nihat Cem, McCoy, Kenneth L., Andrews, Matthew R.
• Primary Examiner(s): Ratcliffe, Luke D
• Assistant Examiner(s): Abraham, Samantha K
• Application Number:
  US13/085,994
• Publication Number:
  US 20110255070A1
• Time in Patent Office: 1,007 Days
• Field of Search: None
• US Class Current: 356/4.01
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/4814 of transmitters alone
• CPC Class Codes: G01S 7/4816 of receivers alone
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G02B 26/12 using multifaceted mirrors
• CPC Class Codes: G02B 5/09 Multifaceted or polygonal mirrors , e.g. polygonal scanning mirrors; Fresnel mirrors

Abstract

A system for determining the speed and position of objects comprises a beam source, a transmit reflection device, a beam receiver, a receive reflection device, and a controller. The beam source may generate a beam. The transmit reflection device may reflect the beam at the objects and may include a plurality of transmit faces with each transmit face oriented at a different angle and operable to reflect the beam at a different height. The beam receiver may detect the beam. The receive reflection device may include a plurality of receive faces with each receive face oriented at a different angle and operable to focus the beam reflected from objects at different heights onto the beam receiver. The controller may determine the position of the objects over time and calculate the speed of the objects based on a change in the position of the objects.

Claims

1. A system for determining the position and speed of objects, the system comprising:

a beam source operable to generate a beam;

a transmit reflection device operable to reflect the beam at the objects, the transmit reflection device including a plurality of transmit faces, at least a portion of the transmit faces oriented at a different angle and operable to reflect the beam at a different height, such that the beam reflection off each transmit face creates a sweep and a portion of each sweep reflected from the first transmit face to the last transmit face overlaps the sweeps adjacent thereto;

a beam receiver operable to detect the beam;

a receive reflection device including a plurality of receive faces, at least a portion of the receive faces oriented at a different angle and operable to focus the beam reflected from objects at different heights onto the beam receiver; and

a controller operable to determine the position of the objects over time and calculate the speed of the objects based on a change in the position of the objects.

2. The system of claim 1, wherein the transmit reflection device further includes a disc-shaped base, a disc-shaped upper stage spaced apart from and of a smaller diameter than the base, and at least three transmit faces that are oriented at a different angle from one another, the transmit faces being positioned in a circle between the upper stage and the base at an angle therebetween and the angle changes by the same amount for consecutively positioned transmit faces.

3. The system of claim 1, wherein each receive face includes an outer surface with a partial circular paraboloid shape operable to focus beams reflecting from objects.

4. The system of claim 1, wherein the receive reflection device further includes a disc-shaped base and a disc-shaped upper stage spaced apart from and of a smaller diameter than the base, the receive faces being positioned in a circle between the upper stage and the base at an angle therebetween and the angle changes by the same amount for consecutively positioned receive faces.

5. The system of claim 4, wherein the receive reflection device is rotatable about a central axis of the base and the upper stage such that each receive face focuses beams at different heights as the receive reflection device rotates.

6. The system of claim 1, further including a motor to rotate the transmit reflection device and the receive reflection device.

7. The system of claim 1, wherein the transmit reflection device is coupled to the receive reflection device such that the transmit faces oppose the receive faces along a vertical axis.

8. A system for determining the position and speed of objects, the system comprising:

a beam source operable to generate a beam;

a transmit reflection device operable to reflect the beam at the objects, the transmit reflection device including;

a transmit base,

a transmit upper stage spaced apart from the transmit base, and

a plurality of transmit faces coupled to the transmit base and the transmit upper stage and positioned in a circle therebetween, at least a portion of the transmit faces oriented at a different angle and operable to reflect the beam at a different height;

a beam receiver operable to detect the beam;

a receive reflection device including;

a receive base,

a receive upper stage spaced apart from the receive base, and

a plurality of receive faces coupled to the receive base and the receive upper stage and positioned in a circle therebetween, at least a portion of the receive faces oriented at a different angle and including an outer surface with a concave partial circular paraboloid shape operable to focus the beam reflected from objects at different heights onto the beam receiver; and

a controller operable to determine the position of the objects over time and calculate the speed of the objects based on a change in the position of the objects.

9. The system of claim 8, wherein the angle at which the transmit faces are positioned between the upper stage and the base changes by the same amount for consecutively positioned transmit faces.

10. The system of claim 8, wherein the transmit reflection device is rotatable about a central axis of the base and the upper stage such that the beam reflects off each transmit face in turn as the transmit reflection device rotates and the beam reflection off each transmit face creates a sweep and the sweep reflected from the first transmit face to the last transmit face overlap one another.

11. The system of claim 8, wherein the angle at which the receive faces are positioned between the upper stage and the base changes by the same amount for consecutively positioned receive faces.

12. The system of claim 8, wherein the receive reflection device is rotatable about a central axis of the base and the upper stage such that each receive face focuses beams at different heights as the receive reflection device rotates.

13. The system of claim 8, further including a motor to rotate the transmit reflection device and the receive reflection device.

14. The system of claim 8, wherein the transmit reflection device is coupled to the receive reflection device such that the transmit faces oppose the receive faces along a vertical axis.

15. A transceiving reflection device for use with a light detection and ranging system, the device comprising:

a transmit reflection device operable to reflect a beam from a beam source into a space in which objects may be present, the transmit reflection device including;

a transmit base,

a transmit upper stage spaced apart from the transmit base, and

a plurality of transmit faces positioned in a circle between the transmit base and the transmit upper stage, the transmit faces oriented at consecutively varying angles from a first transmit face to a last transmit face and operable to reflect the beam at consecutively varying heights; and

a receive reflection device operable to focus the beam onto a beam receiver, the receive reflection device including;

a receive base coupled to the transmit base,

a receive upper stage spaced apart from the receive base, and

a plurality of receive faces positioned in a circle between the receive base and the receive upper stage, the receive faces oriented at consecutively varying angles from a first receive face to a last receive face and operable to focus the beam reflected from objects at different heights onto the beam receiver.

16. The device of claim 15, wherein the transmit faces are positioned opposite the receive faces and each transmit face is aligned along a vertical axis with a receive face.

17. The device of claim 15, wherein each transmit face is planar and oriented at an angle that changes by the same amount for consecutively positioned transmit faces.

18. The device of claim 15, wherein the transmit reflection device is rotatable about a central axis of the base and the upper stage such that the beam reflects off each transmit face in turn as the transmit reflection device rotates and each transmit face is operable to reflect the beam at a different height.

19. The device of claim 15, wherein the beam reflection off each transmit face creates a sweep and the sweep reflected from the first transmit face to the last transmit face overlap one another.

20. The device of claim 15, wherein each receive face includes an outer surface with a partial circular paraboloid shape operable to focus beams reflecting from objects.

21. The device of claim 15, wherein the angle at which the receive faces are positioned between the upper stage and the base changes by the same amount for consecutively positioned receive faces.

22. The device of claim 15, wherein the receive reflection device is rotatable about a central axis of the base and the upper stage such that each receive face focuses beams at different heights as the receive reflection device rotates.

23. The device of claim 15, wherein the transceiving reflection device is monolithically formed as a single unit.

24. A system for determining the position and speed of objects, the system comprising:

a beam source operable to generate a beam;

a transmit device operable to scan the beam at the objects through a known angle in the horizontal direction and a known angle in the vertical direction to create a plurality of horizontally oriented sweeps such that a portion of each sweep overlaps the sweeps adjacent thereto;

a beam receiver operable to detect the beam;

a receive device operable to focus the beam reflected from objects onto the beam receiver; and

a controller operable to determine the position of the objects over time and calculate the speed of the objects based on a change in the position of the objects.

25. The system of claim 24, wherein the transmit device includes:

a transmit base,

a transmit upper stage spaced apart from the transmit base, and

a plurality of transmit faces positioned in a circle between the transmit base and the transmit upper stage, at least a portion of the transmit faces oriented at a different angle therebetween.

26. The system of claim 25, wherein the transmit device is rotatable about a central axis of the base and the upper stage such that the beam reflects off each transmit face in turn as the transmit device rotates and each transmit face is operable to reflect the beam at a different height.

27. The system of claim 24, wherein the receive device includes:

a receive base,

a receive upper stage spaced apart from the receive base, and

a plurality of receive faces positioned in a circle between the receive base and the receive upper stage, at least a portion of the receive faces oriented at a different angle therebetween.

28. The system of claim 27, wherein the receive device is rotatable about a central axis of the base and the upper stage such that each receive face focuses beams at different heights as the receive device rotates.

29. The system of claim 24, further including a motor to provide rotation to the transmit device to scan the beam and the receive device to focus the beam reflected from objects at different positions.

30. The system of claim 24, wherein the transmit device and the receive device include a risley prism assembly operable to refract the beam and including a first wedge prism and a second wedge prism, each wedge prism operable to rotate with respect to the other wedge prism.

31. A system for determining the position and speed of objects, the system comprising:

a beam source operable to generate a beam;

a transmit reflection device operable to reflect the beam at the objects, the transmit reflection device including a plurality of transmit faces positioned adjacent one another in a first circular formation, the transmit faces oriented at consecutively varying angles from a first transmit face to a last transmit face and operable to reflect the beam at consecutively varying heights;

a beam receiver operable to detect the beam;

a receive reflection device opposing the transmit reflection device and including a plurality of receive faces equivalent in number to the transmit faces and positioned adjacent one another in a second circular formation, the receive faces oriented at consecutively varying angles from a first receive face to a last receive face and operable to focus the beam reflected from objects at different heights onto the beam receiver; and

a controller operable to determine the position of the objects over time and calculate the speed of the objects based on a change in the position of the objects.

32. The system of claim 31, wherein the first receive face to the last receive face is aligned with the first transmit face to the last transmit face in consecutive order.

33. The system of claim 31, wherein the transmit reflection device is coupled to the receive reflection device along a plane such that the beam source transmits the beam toward the plane and the beam receiver receives the beam reflected away from the plane.