Laser scanning apparatus and method of use

• US 9,671,094 B2
• Filed: 07/21/2011
• Issued: 06/06/2017
• Est. Priority Date: 07/22/2010
• Status: Expired due to Fees

• Current Assignee: Renishaw PLC
• Original Assignee: Renishaw PLC
• Inventors: Ball, Stephen Leslie
• Primary Examiner(s): RATCLIFFE, LUKE D
• Application Number:
  US13/704,779
• Publication Number:
  US 20130088872A1
• Time in Patent Office: 2,147 Days
• Field of Search: 362259, 356 501
• CPC Class Codes: F21V 21/002 making direct electrical contact, e.g. by piercing F21V21/35 takes precedence
• CPC Class Codes: G01C 11/025 by scanning the object
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G02B 26/108 having one or more prisms as scanning elements

Abstract

A laser system includes a housing and a laser. The laser can be positioned in the housing such that its laser beam is transmitted at an angle and its path forms a cone as the housing rotates. The laser device may also contain two or more lasers, the angle of each laser may be the same or different, and the angular position of each laser may be fixed or variable. The laser system may be stationary or mobile and used in a variety of methods to detect an object or topography and produce a three dimensional image. That information can be further used to provide maps, terrain data, volumetric measurements, landing guidance, obstacle avoidance warnings, mining profiles and other useful material.

Claims

1. A laser scanning apparatus for detecting and describing an object or topography in three dimensions, the apparatus comprising a housing that includes at least one laser, the apparatus being configured to emit at least a first laser beam and a second laser beam from the housing and to rotate the first laser beam and the second laser beam about a common axis of rotation, wherein:

a path of the first laser beam forms a shape of a first cone when the first laser beam rotates about the common axis of rotation,

a path of the second laser beam forms a shape of a second cone when the second laser beam rotates about the common axis of rotation, and

the first cone and the second cone face in opposite directions.

2. The laser apparatus, as claimed in claim 1, in which the at least first and second laser beams are rotationally fixed relative to each other.

3. The laser apparatus, as claimed in claim 1, in which the housing is rotatable about an axis of rotation, and the at least first and second laser beams are configured to rotate with the housing.

4. The laser apparatus, as claimed in claim 3, in which the at least first and second lasers are positioned in the housing at an angle such that the path of their laser beams are each in the shape of a cone when the housing moves about its axis of rotation.

5. The laser apparatus, as claimed in claim 1 that is configured to process reflected or backscattered beams from surroundings in which the apparatus is located to determine a series of measurements relating to a distance between the apparatus and the surroundings, and to use the measurements, together with information associated with each measurement relating to an emission position and direction of the laser beam used for the measurement to create a cloud of measured points representing the topography of the surroundings.

6. The laser apparatus, as claimed in claim 5, in which the apparatus is configured to tie together measurements obtained from the detection of the reflection or backscattering of each of the at least first and second beams.

7. The laser apparatus, as claimed in claim 5, in which the apparatus is configured to generate from the cloud of measurement points a 3D model, map or image of the surroundings in which the apparatus is located.

8. The laser apparatus, as claimed in claim 1, in which each of the at least first and second laser beams is configured to rotate about a common bearing.

9. The laser apparatus, as claimed in claim 1, in which each of the at least first and second laser beams is caused to rotate about the common axis of rotation by a common rotation device.

10. An apparatus as claimed in claim 1, in which the first and second laser beams are projected at an acute angle between 80°

and 5°

relative to the common axis of rotation.

11. An apparatus as claimed in claim 1, in which the first and second laser beams are projected at an acute angle between 70°

and 10°

relative to the common axis of rotation.

12. An apparatus as claimed in claim 1, in which the first and second laser beams are projected at an acute angle between 60°

and 20°

relative to the common axis of rotation.

13. An apparatus as claimed in claim 1, mounted to means for linearly moving the housing in a direction substantially parallel to the axis of rotation.

14. A laser scanning system comprising a laser scanning apparatus as claimed in claim 1 mounted to means for moving the laser scanning apparatus during a scanning operation for detecting and describing an object or topography in three dimensions.

15. A laser scanning system as claimed in claim 14, wherein one of the first and second laser beams describes a forward facing cone and the other describes a rearward facing cone relative to a direction of travel.

16. A laser scanning system as claimed in claim 14, wherein at least one of the laser beams describes a sideways facing cone.

17. A laser scanning system as claimed in claim 14, wherein the common axis of rotation of the first and second laser beams is arranged substantially parallel to a direction of travel.

18. A laser scanning system as claimed in claim 14, wherein the means for moving the laser scanning apparatus comprises a vehicle, such as an airplane, helicopter, automobile, motorcycle, military vehicle or boat.

19. A laser scanning system as claimed in claim 14, wherein the means for moving the laser scanning apparatus comprises a boom.

20. The laser apparatus, as claimed in claim 1, wherein:

the first laser beam is projected at an angle to the common axis of rotation; and

the second laser beam is projected at an angle to the common axis of rotation.

21. The laser apparatus, as claimed in claim 1, wherein:

the first laser beam is projected at a non-perpendicular angle to the common axis of rotation, and

the second laser beam is projected at a non-perpendicular angle to the common axis of rotation.

22. The laser apparatus, as claimed in claim 1, wherein:

the first laser beam is projected at a constant angle to the common axis of rotation, and

the second laser beam is projected at a constant angle to the common axis of rotation.

23. A method of scanning using a laser scanning apparatus comprising a housing from which at least first and second beams are emitted from the housing, the method comprising:

rotating the at least first and second beams about a common axis wherein;

the first and second beams define a first and second conical path, respectively,

the first conical path forms a shape of a first cone when the first laser beam rotates about the common axis of rotation,

the second conical path forms a shape of a second cone when the second laser beam rotates about the common axis of rotation, and

the first and second conical paths face in opposite directions.

24. A method as claimed in claim 23, in which the method comprises rotating the housing so as to rotate the at least first and second beams about the common axis.

25. A method as claimed in claim 23, comprising:

processing reflected or backscattered beams from the surroundings in which the apparatus is located to determine a series of measurements relating to the distance between the apparatus and the surroundings, and

using the measurements, together with information associated with each measurement relating to an emission position and direction of the laser beam used for that measurement, to create a cloud of measurement points representing the topography of the surroundings.

26. The method as claimed in claim 23, further comprising linearly moving the housing in a direction substantially parallel to the axis of rotation.

27. A method of detecting and describing an object or topography in three dimensions, comprising:

moving a laser scanning apparatus past the object or topography, wherein the laser scanning apparatus projects at least one laser beam at an angle relative to the direction of travel so as to extend in both forward and backward directions relative to the direction of travel as the laser scanning apparatus moves past the object or topography so as to obtain data relating to both front and rear faces or surfaces of the object or topography in a single pass, and

using the data to generate a 3D model, map or image of the object or topography, wherein the laser scanning apparatus either projects at least a first laser beam and a second laser beam, one in the forward direction and another in the backward direction, or projects a single beam that moves between the forward and backward directions, wherein when the laser scanning apparatus projects the first laser beam and the second laser beam;

a path of the first laser beam forms a shape of a first cone when the first laser beam rotates about the common axis of rotation;

a path of the second laser beam forms a shape of a second cone when the second laser beam rotates about the common axis of rotation; and

the first cone and the second cone face in opposite directions.

28. A method as claimed in claim 27, wherein the single beam moves between the forward and backward directions in a fan beam pattern.

29. A method as claimed in claim 27, wherein the single beam moves between the forward and backward directions in a cone beam pattern.

30. A laser scanning system for detecting and describing an object or topography in three dimensions, comprising:

a vehicle or a boom that moves a laser scanning apparatus past the object or topography, wherein the laser scanning apparatus is arranged to project at least a first laser beam and a second laser beam at an angle relative to the direction of travel so as to extend in both forward and backward directions relative to the direction of travel as the laser scanning apparatus moves past the object or topography so as to obtain data relating to both front and rear faces or surfaces of the object or topography in a single pass, and

a processor that processes the obtained data to generate a 3D model, map or image of the object or topography, wherein;

the first laser beam and the second laser beam rotate about a common axis of rotation,

a path of the first laser beam forms a shape of a first cone when the first laser beam rotates about the common axis of rotation,

a path of the second laser beam forms a shape of a second cone when the second laser beam rotates about the common axis of rotation, and

the first cone and the second cone face in opposite directions.