Method and apparatus for using gestures to control a laser tracker

• US 9,234,742 B2
• Filed: 04/29/2014
• Issued: 01/12/2016
• Est. Priority Date: 05/01/2013
• Status: Active Grant

• Current Assignee: Faro Technologies Incorporated
• Original Assignee: Faro Technologies Incorporated
• Inventors: Bridges, Robert E., Parker, David H., Fletcher, Kelley, Pease, Gregory D., Mehler, Robert C
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US14/264,420
• Publication Number:
  US 20140327920A1
• Time in Patent Office: 623 Days
• Field of Search: 356/614, 356/625, 356/445, 356/4.01, 356/138, 356/139.03, 348/169, 348/135, 250/203.1
• US Class Current: 1/1
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/14 for measuring distance or clearance between spaced objects or spaced apertures G01B11/26 takes precedence; rangefinders G01C3/00
• CPC Class Codes: G01C 15/002 Active optical surveying means optical plumbing G01C15/105
• 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 3/786 the desired condition being maintained automatically
• CPC Class Codes: G06F 3/015 Input arrangements based on nervous system activity detection, e.g. brain waves [EEG] detection, electromyograms [EMG] detection, electrodermal response detection
• CPC Class Codes: G06F 3/017 Gesture based interaction, e.g. based on a set of recognized hand gestures interaction based on gestures traced on a digitiser G06F3/04883
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/20224 Image subtraction
• CPC Class Codes: G06T 2207/30196 Human being; Person
• CPC Class Codes: G06T 7/12 Edge-based segmentation
• CPC Class Codes: G06T 7/174 involving the use of two or more images
• CPC Class Codes: G06T 7/194 involving foreground-background segmentation
• CPC Class Codes: G06T 7/254 involving subtraction of images
• CPC Class Codes: G06T 7/30 Determination of transform parameters for the alignment of images, i.e. image registration
• CPC Class Codes: G06V 40/20 Movements or behaviour, e.g. gesture recognition recognition of facial expressions G06V40/16
• CPC Class Codes: G06V 40/28 Recognition of hand or arm movements, e.g. recognition of deaf sign language static hand signs G06V40/113

Abstract

A method and system are provided for controlling a laser tracker remotely from the laser tracker through gestures performed by a user. The method includes providing a rule of correspondence between each of a plurality of commands and each of a plurality of user gestures. A gesture is performed by the user with the user'"'"'s body that corresponds to one of the plurality of user gestures. The gesture performed by the user is detected. The gesture recognition engine determines a first command from one of the plurality of commands that correspond with the detected gesture. Then the first command is executed with the laser tracker.

Claims

1. A method for communicating, from a user to a laser tracker with steps comprising:

providing the laser tracker having a structure rotatable about a first axis and a second axis, a first light source that launches a first light beam from the structure, a distance meter, a first angular encoder that measures a first angle of rotation about the first axis, a second angular encoder that measures a second angle of rotation about the second axis, and a processor;

providing a projector and a first camera;

providing a rule of correspondence between each of a plurality of commands and each of a plurality of gestures, each gesture from among the plurality of gestures including a spatial configuration of a first body part of the user relative to a second body part of the user, the rule of correspondence based at least in part on the spatial configuration;

performing by the user a first gesture from among the plurality of gestures, the first gesture corresponding to a first command;

projecting from the projector a second light onto the first body part and second body part, the second light being a two-dimensional pattern of light;

reflecting the second light from the first body part and second body part as a third light;

capturing a portion of the third light with the first camera to obtain a digital representation of the portion of the third light;

determining the first command based at least in part on processing the digital representation according to the rule of correspondence;

executing the first command with the laser tracker; and

measuring three dimensional coordinates of a retroreflector based at least in part on measurements of the distance meter, the first angular encoder, the second angular encoder and a speed of light.

2. The method of claim 1 wherein, in the step of providing a projector and a first camera, the projector and the first camera are attached to the laser tracker.

3. The method of claim 1 wherein the step of determining the first command based at least in part on processing the digital representation further includes determining at least one three-dimensional coordinate for the first body part and one three-dimensional coordinate for the second body part, wherein the three-dimensional coordinates of the first body part and the second body part are based at least in part on the two-dimensional pattern of light.

4. The method of claim 3 wherein the step of determining the first command based at least in part on processing the digital representation further includes using a distance between the first camera and the projector.

5. The method of claim 1 wherein, in the step of providing a projector and a first camera, the projector and the first camera are attached to the structure.

6. The method of claim 1 wherein, in the step of providing a projector and a first camera, the projector and the first camera are attached to a portion of the laser tracker that rotates relative to the first axis and is fixed relative to the second axis.

7. The method of claim 1 wherein in the step of performing a first gesture, the first body part of the user is a first finger and the second body part of the user is a second finger.

8. The method of claim 1 wherein the step of determining the first command further includes determining a confidence level of the first command.

9. The method of claim 1 wherein the step of determining the first command further includes a step of indicating to the user that the first gesture has been recognized.

10. The method of claim 1 wherein in the step of determining the first command, the first command is selected from the group consisting of measuring a comp off point, measuring a comp axis point, measuring a plane, measuring a 2D line, measuring a circle, measuring a cylinder, measuring a sphere, changing an SMR, resetting an interferometer, setting a distance mode, searching for a target, toggling between single point mode and scan mode, collecting a reading, moving to a home position, removing a reading, autoadjusting an ADM using an SMR, autoadjusting an ADM using an internal retroreflector, initializing a command tablet, setting an SMR, and acquiring an SMR.

11. The method of claim 1 wherein the step of providing the laser tracker further includes providing a second camera and an auxiliary light source proximate to the second camera.

12. The method of claim 11 wherein the step of executing the first command further includes illuminating the auxiliary light source to obtain a fourth light, reflecting the fourth light off a retroreflector, and capturing a portion of the fourth light with the second camera to obtain a digital representation of the portion of the fourth light.

13. The method of claim 12 wherein the step of executing the first command further includes rotating the structure about at least one of the first axis and the second axis to place the first light beam onto the retroreflector.

14. A method for communicating, from a user to a laser tracker, to control operation of the laser tracker with steps comprising:

providing the laser tracker having a structure rotatable about a first axis and a second axis, a first light source that launches a first light beam from the structure, a distance meter, a first angular encoder that measures a first angle of rotation about the first axis, a second angular encoder that measures a second angle of rotation about the second axis, and a processor;

providing a camera having a field of view;

providing a rule of correspondence between each of a plurality of commands for controlling a laser tracker and each of a plurality of gestures, each gesture from among the plurality of gestures including a spatial configuration of a first body part of the user relative to a second body part of the user, the rule of correspondence based at least in part on the spatial configuration;

tracking at least a portion of the user from a first position to a second position within the field of view, the tracking based at least in part on a first image acquired by the camera;

performing a first gesture by the user from among the plurality of gestures, the first gesture corresponding to a first command from the plurality of commands;

acquiring a second image with the camera of the first gesture that includes the first body part and second body part;

determining the first command based at least in part on the spatial configuration of the first body part and second body part in the second image;

executing the first command with the laser tracker; and

determining with the processor a set of three dimensional coordinates of at least one point on an object based at least in part on the first light beam, the distance meter, the first angle of rotation, the second angle of rotation and a speed of light.

15. The method of claim 14, further comprising identifying a first retroreflector based at least in part on a third image acquired by the camera in response to executing the first command.

16. The method of claim 15 wherein the first image and third image are the same image.

17. The method of claim 14 further comprising rotating the structure about the first axis and second axis while tracking the user.

18. The method of claim 15 further comprising:

performing a second gesture from among the plurality of gestures, the second gesture corresponding to a second command from the plurality of commands;

acquiring a fourth image with the camera of the second gesture that includes the first body part and second body part;

determining the second command based at least in part on the spatial configuration of the first body part and second body part in the fourth image; and

executing the second command with the laser tracker.

19. The method of claim 18 further comprising emitting the first light beam toward the identified first retroreflector, and determining a distance from the laser tracker to the identified first retroreflector with the distance meter.

20. The method of claim 19 wherein the first gesture includes pointing the user'"'"'s finger at the first retroreflector.

21. The method of claim 14 further comprising:

tracking at least a portion of the user from the second position to a third position based at least in part on a fifth image acquired by the camera;

performing a third gesture from among the plurality of gestures, the third gesture corresponding to a third command from the plurality of commands;

determining the third command based at least in part on the spatial configuration of the first body part and second body part in the fifth image; and

executing the third command with the laser tracker.

22. The method of claim 21 further comprising identifying a second retroreflector based at least in part on fifth image.