Using a two-dimensional scanner to speed registration of three-dimensional scan data

• US 10,120,075 B2
• Filed: 08/11/2017
• Issued: 11/06/2018
• Est. Priority Date: 08/19/2016
• Status: Active Grant

• Current Assignee: Faro Technologies Incorporated
• Original Assignee: Faro Technologies Incorporated
• Inventors: Frank, Aleksej, Zweigle, Oliver
• Primary Examiner(s): Pham, Hoa
• Application Number:
  US15/675,006
• Publication Number:
  US 20180052233A1
• Time in Patent Office: 452 Days
• Field of Search: 356601-623
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• CPC Class Codes: G01C 3/06 Use of electric means to obtain final indication
• CPC Class Codes: G01S 17/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4808 Evaluating distance, position or velocity data
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 7/344 involving models
• CPC Class Codes: H04N 1/00827 Arrangements for reading an image from an unusual original, e.g. 3-dimensional objects
• CPC Class Codes: H04N 1/1135 for the main-scan only
• CPC Class Codes: H04N 1/12 using the sheet-feed movement or the medium-advance or the drum-rotation movement as the slow scanning component, e.g. arrangements for the main-scanningsheet-feed movement by translatory movement of a flat picture-bearing surface H04N1/1008; main-scanning using oscillating or rotating mirrors H04N1/113; using multi-element arrays H04N1/19
• CPC Class Codes: H04N 2201/04789 in the main-scan direction

Abstract

A method and system for generating a three-dimensional (3D) map of an environment is provided. An example method includes receiving, by a processor system, via a 3D scanner, located at a scan position, a 3D scan of the environment. The method further includes receiving via a two-dimensional (2D) scanner accessory, a portion of a 2d map of the environment. The method further includes receiving coordinates of the scan position in the 2d map in response to the 3D scanner initiating the acquisition of the 3D scan. The method further includes associating the coordinates of the scan position with the portion of the 2D map. The method further includes determining a displacement vector for the 2D map using a loop closure algorithm. The method further includes computing a revised scan position based on the scan position and the displacement vector, where the 3D scan is registered using the revised scan position.

Claims

1. A three-dimensional (3D) measuring device comprising:

a processor system including at least one of a 3D scanner controller, a two-dimensional (2D) scanner processor;

a 3D scanner operable to cooperate with the processor system to determine 3D coordinates;

a 2D scanner accessory including a 2D scanner operable to cooperate with the processor system to determine 3D coordinates;

a moveable platform operable to carry the 3D scanner and the 2D scanner, the 3D scanner being fixed relative to the 2D scanner;

wherein the processor system is responsive to executable instructions which when executed by the processor system is operable to;

cause the 3D scanner, while fixedly located at a scan position, to cooperate with the processor system to acquire a 3D scan of an environment;

cause the 2D scanner to cooperate with the processor system to acquire a portion of a 2D map of the environment;

cause the 2D scanner to determine coordinates of the scan position in the 2D map in response to the 3D scanner initiating the acquisition of the 3D scan;

link the coordinates of the scan position with the portion of the 2D map;

determine a displacement vector for the 2D map using a loop closure algorithm;

compute a revised scan position based on the scan position and the displacement vector; and

register the 3D scan using the revised scan position.

2. The 3D measuring device of claim 1, wherein the 2D scanner accessory further includes a position/orientation sensor, the position orientation sensor includes at least one sensor selected from the group consisting of an inclinometer, a gyroscope, a magnetometer, and an altimeter.

3. The 3D measuring device of claim 1, wherein the moveable platform is a tripod having wheels and a brake.

4. The 3D measuring device of claim 1, wherein the 3D scanner comprises a first light source, a first beam steering unit, a first angle measuring device, a second angle measuring device, and a first light receiver, the first light source operable to emit a first beam of light, the first beam steering unit operable to steer the first beam of light to a first direction onto a first object point, the first direction determined by a first angle of rotation about a first axis and a second angle of rotation about a second axis, the first angle measuring device operable to measure the first angle of rotation and the second angle measuring device operable to measure the second angle of rotation, the first light receiver operable to receive first reflected light, the first reflected light being a portion of the first beam of light reflected by the first object point, the first light receiver operable to produce a first electrical signal in response to the first reflected light, the first light receiver operable to cooperate with the processor system to determine a first distance to the first object point based at least in part on the first electrical signal, the 3D scanner operable to cooperate with the processor system to determine 3D coordinates of the first object point based at least in part on the first distance, the first angle of rotation and the second angle of rotation.

5. The 3D measuring device of claim 4, wherein the 2D scanner comprises a second light source, a second beam steering unit, a third angle measuring device, and a second light receiver, the second light source operable to emit a second beam of light, the second beam steering unit operable to steer the second beam of light to a second direction onto a second object point, the second direction determined by a third angle of rotation about a third axis, the third angle measuring device operable to measure the third angle of rotation, the second light receiver operable to receive second reflected light, the second reflected light being a portion of the second beam of light reflected by the second object point, the second light receiver operable to produce a second electrical signal in response to the second reflected light, the 2D scanner operable to cooperate with the processor system to determine a second distance to the second object point based at least in part on the second electrical signal, the 2D scanner further operable to cooperate with the processor system to determine 2D coordinates of the second object point based at least in part on the second distance and the third angle of rotation.

6. The 3D measuring device of claim 4, wherein the first beam steering unit includes a first mirror operable to rotate about a horizontal axis and a carriage that holds the first mirror operable to rotate about a vertical axis, the rotation about the horizontal axis being driven by a first motor and the rotation about the vertical axis being driven by a second motor.

7. The 3D measuring device of claim 1, wherein the loop closure algorithm determines the displacement vector, which is representative of an error in estimating the coordinates of the scan position.

8. A method for generating a three-dimensional (3D) map of an environment, the method comprising:

receiving, by a processor system, via a 3D scanner, which is fixedly located at a scan position, a 3D scan of the environment;

receiving, by the processor system, via a two-dimensional (2D) scanner accessory, a portion of a 2D map of the environment;

receiving, by the processor system, coordinates of the scan position in the 2D map in response to the 3D scanner initiating the acquisition of the 3D scan;

associating, by the processor system, the coordinates of the scan position with the portion of the 2D map;

determining, by the processor system, a displacement vector for the 2D map using a loop closure algorithm; and

computing, by the processor system, a revised scan position based on the scan position and the displacement vector, wherein the 3D scan is registered using the revised scan position.

9. The method of claim 8, wherein the 2D scanner accessory further includes a position/orientation sensor, the position orientation sensor includes at least one sensor selected from the group consisting of an inclinometer, a gyroscope, a magnetometer, and an altimeter.

10. The method of claim 8, further comprising, mounting the 3D scanner and the 2D scanner accessory are on a moveable platform, the moveable platform being a tripod having wheels and a brake.

11. The method of claim 8, wherein the 3D scanner comprises a first light source, a first beam steering unit, a first angle measuring device, a second angle measuring device, and a first light receiver, the first light source operable to emit a first beam of light, the first beam steering unit operable to steer the first beam of light to a first direction onto a first object point, the first direction determined by a first angle of rotation about a first axis and a second angle of rotation about a second axis, the first angle measuring device operable to measure the first angle of rotation and the second angle measuring device operable to measure the second angle of rotation, the first light receiver operable to receive first reflected light, the first reflected light being a portion of the first beam of light reflected by the first object point, the first light receiver operable to produce a first electrical signal in response to the first reflected light, the first light receiver operable to cooperate with the processor system to determine a first distance to the first object point based at least in part on the first electrical signal, the 3D scanner operable to cooperate with the processor system to determine 3D coordinates of the first object point based at least in part on the first distance, the first angle of rotation and the second angle of rotation.

12. The method of claim 11, wherein the 2D scanner comprises a second light source, a second beam steering unit, a third angle measuring device, and a second light receiver, the second light source operable to emit a second beam of light, the second beam steering unit operable to steer the second beam of light to a second direction onto a second object point, the second direction determined by a third angle of rotation about a third axis, the third angle measuring device operable to measure the third angle of rotation, the second light receiver operable to receive second reflected light, the second reflected light being a portion of the second beam of light reflected by the second object point, the second light receiver operable to produce a second electrical signal in response to the second reflected light, the 2D scanner operable to cooperate with the processor system to determine a second distance to the second object point based at least in part on the second electrical signal, the 2D scanner further operable to cooperate with the processor system to determine 2D coordinates of the second object point based at least in part on the second distance and the third angle of rotation.

13. The method of claim 11, wherein the first beam steering unit includes a first mirror operable to rotate about a horizontal axis and a carriage that holds the first mirror operable to rotate about a vertical axis, the rotation about the horizontal axis being driven by a first motor and the rotation about the vertical axis being driven by a second motor.

14. The method of claim 8, wherein the loop closure algorithm determines the displacement vector, which is representative of an error in estimating the coordinates of the scan position.