AERIAL ROBOT POSITIONING SYSTEM UTILIZING A LIGHT BEAM MEASUREMENT DEVICE

Abstract

A light-based measurement system is capable of directing a light beam to a cooperative target used in conjunction with an aerial robot to accurately control the position of the end effector within a large volume working environment defined by a single coordinate system. By measuring the end effector while the device is in operation, the aerial robot control system can be adjusted in real time to correct for errors that are introduced through the design of the robot itself providing accuracy in the tens or hundreds of micron range. A separate coordination computer runs control software that communicates with both the laser tracker and the aerial robot. An action plan file is loaded by the software that defines the coordinate system of the working volume, the locations where actions need to be performed by the aerial robot, and the actions to be taken.

Claims

1. An aerial robot position control system comprising: a) a light beam position measurement system comprising: i) a measurement source that produces an emitted measurement beam that is a light beam; and ii) a cooperative target configured within a device coordinate system that has a target location with respect to the measurement source, which is target data; b) a coordination processor configured to run a control algorithm comprising: i) an input measured position; ii) an output motor command; and iii) end effector activator instructions; c) an aerial robot comprising: i) a position driver comprising: a propeller; and a motor that spins the propeller; and ii) an end effector; wherein said emitted measurement beam is incident on said cooperative target such that said light beam position measurement system produces said target location within a device coordinate system, which is said target data; wherein said target data is provided as an input measured position to said control algorithm to generate said robot positional instructions and said end effector activator instructions; wherein said aerial robot receives said output motor command and operates said position driver to set a position of said end effector; wherein said aerial robot receives said end effector activator instructions and operates said end effector; wherein said cooperative target is coupled with said aerial robot in a fixed positional relationship to said end effector; and wherein said measurement source is in a fixed location within said working coordinate system.

2. (canceled)

3. The aerial robot system of claim 1, wherein said end effector comprises a nozzle configured to deliver a printable material.

4. The aerial robot system of claim 3, wherein said printable material is paint.

5. The aerial robot system of claim 3, wherein said printable material comprises plastic.

6. The aerial robot system of claim 3, wherein said printable material comprises concrete.

7. The aerial robot system of claim 3, wherein said printable material comprises metal.

8. The aerial robot system of claim 1, wherein said end effector is a gripper actuator.

9. (canceled)

10. (canceled)

11. The aerial robot system of claim 1, wherein said end effector is a non-contact measurement device.

12. The aerial robot system of claim 1, wherein said end effector is a contact measurement device.

13. The aerial robot system of claim 1, wherein said end effector is a camera.

14. The aerial robot system of claim 1, further comprising an end effector position mechanism configured between the aerial robot and the end effector and configured to move the end effector independently of said aerial robot.

15. (canceled)

16. (canceled)

17. (canceled)

18. (canceled)

19. (canceled)

20. An aerial robot position control system comprising: a) a light beam position measurement system comprising: i) a measurement source that produces an emitted measurement beam that is a light beam; and ii) a cooperative target configured within a device coordinate system that has a target location with respect to the measurement source, which is target data; b) a coordination processor configured to run a control algorithm comprising: i) an input measured position; ii) an output motor command; and iii) end effector activator instructions; c) an aerial robot comprising: i) a position driver comprising: a propeller; and a motor that spins the propeller; and ii) an end effector; wherein said emitted measurement beam is incident on said cooperative target such that said light beam position measurement system produces said target location within a device coordinate system, which is said target data; wherein said target data is provided as an input measured position to said control algorithm to generate said robot positional instructions and said end effector activator instructions; wherein said aerial robot receives said output motor command and operates said position driver to set a position of said end effector; and wherein said aerial robot receives said end effector activator instructions and operates said end effector; wherein said measurement source is coupled with said aerial robot in a fixed positional relationship to said end effector; and wherein said cooperative target is in a fixed location within said working coordinate system.

21. The aerial robot system of claim 20, wherein said end effector comprises a nozzle configured to deliver a printable material.

22. The aerial robot system of claim 21, wherein said printable material is paint.

23. The aerial robot system of claim 21, wherein said printable material comprises plastic.

24. The aerial robot system of claim 21, wherein said printable material comprises concrete.

25. The aerial robot system of claim 21, wherein said printable material comprises metal.

26. The aerial robot system of claim 20, wherein said end effector is a gripper.

27. (canceled)

28. (canceled)

29. The aerial robot system of claim 20, wherein said end effector is a non-contact measurement device.

30. The aerial robot system of claim 20, wherein said end effector is a contact measurement device.

31. The aerial robot system of claim 20, wherein said end effector is a camera.

32. The aerial robot system of claim 20, further comprising an end effector position mechanism configured between the aerial robot and the end effector and configured to move the end effector independently of said aerial robot.

33. (canceled)

34. (canceled)

35. (canceled)

36. (canceled)

37. (canceled)

38. (canceled)

39. The aerial robot system of claim 1 wherein said cooperative reflective target is a retro reflector assembly comprising: a) two or more retro reflectors; and b) a retroreflector mounting structure wherein said two or mor retroreflectors are coupled to said retroreflector mounting structure such that their relationship to each other is known; where said measurement source measures said two or more retroreflectors such that said target data represents four or more degrees of freedom.

40. The aerial robot system of claim 1 wherein said cooperative reflective target is a light receiving target capable of measuring one or more degrees of freedom such that said target data represents four or more degrees of freedom.

41. (canceled)

42. (canceled)

43. The aerial robot system of claim 1, wherein said cooperative reflective target is a 6 degree of freedom target.

44. The aerial robot system of claim 1, wherein said a measurement source is a laser tracker.

45. The aerial robot system of claim 20 wherein said cooperative reflective target is a retro reflector assembly comprising: c) two or more retro reflectors; and d) a retroreflector mounting structure wherein said two or mor retroreflectors are coupled to said retroreflector mounting structure such that their relationship to each other is known; where said measurement source measures said two or more retroreflectors such that said target data represents four or more degrees of freedom.

46. The aerial robot system of claim 20 wherein said cooperative reflective target is a light receiving target capable of measuring one or more degrees of freedom such that said target data represents four or more degrees of freedom.

47. The aerial robot system of claim 20, wherein said cooperative reflective target is a 6 degree of freedom target.

48. The aerial robot system of claim 20, wherein said a measurement source is a laser tracker.

Description

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0062] The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.

[0063] FIG. 1 is a perspective view of an exemplary aerial robot system where the coordination processor is a separate device.

[0064] FIG. 2 is a perspective view of an exemplary aerial robot system where the coordination processor is integrated with the source measurement device.

[0065] FIG. 3 is a perspective view of an exemplary aerial robot system where the coordination processor is integrated with the aerial robot.

[0066] FIG. 4 is a perspective view of an exemplary aerial robot mechanical assembly.

[0067] FIG. 5 is a top view of an exemplary motor configuration.

[0068] FIG. 6 is a top view of an exemplary motor rotating counter-clockwise.

[0069] FIG. 7 is a top view of an exemplary motor rotating clockwise.

[0070] FIG. 8 is a perspective view of an exemplary nozzle distributing printable material.

[0071] FIG. 9 is a perspective view of an exemplary gripper.

[0072] FIG. 10 is a perspective view of an exemplary screed tool used in conjunction with a light receiving target.

[0073] FIG. 11 is a perspective view of an exemplary tamper with the measurement source mounted to aerial robot.

[0074] FIG. 12 is a perspective view of an exemplary aerial robot system with two aerial robots and a single measurement source.

[0075] FIG. 13 is a perspective view of an exemplary aerial robot system with two measurement sources and a single aerial robot with a non-contact measurement probe.

[0076] FIG. 14 is a perspective view of an exemplary measurement source with a target camera showing the camera's field of view used in conjunction with a contact measurement device.

[0077] FIG. 15 is a side view an exemplary end effector position mechanism.

[0078] FIG. 16 is an exemplary coordination processor with an action plan.

[0079] FIG. 17 is an exemplary motion control algorithm.

[0080] FIG. 18 is an exemplary light beam position measurement system with a single retro reflector.

[0081] FIG. 19 is a perspective view of an exemplary measurement source.

[0082] FIG. 20 is a perspective view of an exemplary light beam position measurement system with a laser tracker and a light receiving target.

[0083] FIG. 21 is a perspective view of an exemplary retro reflector.

[0084] FIG. 22 is a perspective view of an exemplary partially transmissive retro reflector.

[0085] FIG. 23 is a perspective view of an exemplary retro sphere.

[0086] FIG. 24 is a perspective view of an exemplary light receiving target.

[0087] FIG. 25 is a perspective view of an exemplary retro reflector assembly.

[0088] FIG. 26 is a perspective view of an exemplary aerial robot system where the light beam measurement device does not have a beam steering capability.

[0089] FIG. 27 is a perspective view of an exemplary camera-assisted 6 degree of freedom (DOF) target.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0090] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Also, use of “a” or “an” are employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

[0091] Certain exemplary embodiments of the present invention are described herein and are illustrated in the accompanying figures. The embodiments described are only for purposes of illustrating the present invention and should not be interpreted as limiting the scope of the invention. Other embodiments of the invention, and certain modifications, combinations and improvements of the described embodiments, will occur to those skilled in the art and all such alternate embodiments, combinations, modifications, improvements are within the scope of the present invention.

[0092] FIG. 1 is an exemplary aerial robot system with an aerial robot 130 with end effector 131 coupled with a cooperative target 105. A measurement source 101 transmits an emitted measurement beam 102 for which of portion is reflected back by said cooperative target as a reflected measurement beam 103. Said measurement source produces target data 127 that is transmitted to a coordination processor 126, which is a computer 135, such as a laptop computer, running a control algorithm 148. Said computer processes an action plan 132 and sends an action output 128 to said aerial robot to position it and perform actions in the working volume defined by a working coordinate system 129. Beam steering is accomplished by a moveable mirror that can reflect the beam in two angles.

[0093] FIG. 2 is an exemplary measurement source 101 that has an integrated coordination processor 126 so that a separate external computer is not required. Beam steering is accomplished by a two-axis gimbal that steers the entire optical assembly.

[0094] FIG. 3 is an exemplary aerial robot 130 that has an integrated coordination processor 126 so that a separate external computer is not required.

[0095] FIG. 4 is an exemplary aerial robot mechanical assembly 5001 in a quadcopter configuration that has two motors 5002, 5002′ rotating in a first direction, two motors 5003, 5003′ rotating in a second direction, and an end effector 131 mounted to an aerial robot mounting structure 5021.

[0096] FIG. 5 shows an exemplary position driver 5023. If the speed of the two motors 5002, 5002′ rotating in a first direction is different than the speed of two motors 5003, 5003′ rotating in a second direction, the aerial robot will move in a yaw direction 5020. If the speed of left pair of motors 50 14, 5014′ is different than right pair of motors 5015, 5015′, the aerial robot will roll and cause a side-to-side motion 5018 of the aerial robot. If the speed of the front pair of motors 5016, 5016′ is different than the back pair of motors 5017, 5017′ the aerial robot will pitch and cause a forward-reverse motion 5019 of the aerial robot.

[0097] FIG. 6 shows one or more motors coupled with propellers 5022, which is a motor 5002 rotating in a first direction with a first propeller 5004 such then when rotating counter-clockwise 5009 from the top view will create lift. A first motor cable 5008 carrying one or more voltages and current represent a first motor signal output 5006 connected to a first motor signal input 5007 that controls the speed of rotation.

[0098] FIG. 7 shows an exemplary motor 5003 rotating in a second direction 5013 with a second propeller 5005 such then when rotation in a clockwise direction 5013 will create lift. A second motor cable 5012 carrying one or more voltages and current represent a second motor signal output 5010 connected to a second motor signal input 5012 that controls the speed of rotation.

[0099] FIG. 8 shows an exemplary aerial robot 130 with an end effector 131, which is a nozzle 5101 capable of dispensing a printable material 5102 that hardens into a material such as hardened plastic 5103, hardened concrete 5104, or hardened metal 5105,

[0100] FIG. 9 is an exemplary gripper 5108 capable of picking up and placing and exemplary object such as a brick 5109. The exemplary gripper 5108 is an actuator type end effector having at least one of the gripper arms that actuates toward the other gripper arm. The gripper 5109 is holding a brick 5109′, picked up from the stack of bricks. The exemplary gripper is coupled to an end effector position mechanism 5900 that extends from the aerial robot 130 to the end effector 131, the gripper 5108 actuator. The exemplary end effector position mechanism 5900 has a coupled arm 5902 that is coupled with or attached to the aerial robot 130 and an extended arm 5906 that has the end effector 131 coupled or attached thereto. The extended arm is coupled to the coupled arm by an end effector position mechanism actuator 5904, such as a pivoting and/or rotating joint or coupling between the coupled arm and the extended arm. As shown, the end effector position mechanism actuator 5904 enables pivoting between the coupled arm and the extended arm. The coupled arm may have a rotational engagement or coupling with the aerial robot to provide an additional degree of freedom of rotation. An end effector position mechanism actuator may provide translational motion, rotational motion, and/or pivoting motion between a coupled arm and an extended arm of the end effector position mechanism. Also, any number of end effector position mechanism arms may be configured between a coupled arm and an extended arm to provide additional degrees of freedom.

[0101] FIG. 10 shows an exemplary screed tool 5110 that is pulled across poured concrete 5111 to level it. In this application, it is important to control yaw, so the cooperative target 105, is a light receiving target 5201 capable of measuring yaw.

[0102] FIG. 11 shows an exemplary tamper 5112 used to compact a construction material such as sand 5113. Measurement source 101 is mounted to aerial robot 130 in a known and fixed relationship to the end effector 131 and points to a cooperative target 105 mounted in a fixed location.

[0103] FIG. 12 shows an exemplary aerial robot system where a single measurement source 101 measures the position of a first aerial robot 5204 and a second aerial robot 5205 by alternately pointing the emitted measurement beam 102 along a first measurement path 5206 and a second measurement path 5207. An exemplary retroreflector assembly 1104 is shown where said measurement source alternately measures the location of the reflective targets to calculate locations with six degrees of freedom. An exemplary nozzle 5101 delivers a printable material 5102 that is paint 5202 for an application to paint lines for parking spaces 5203. An exemplary camera 5118 captures images.

[0104] FIG. 13 shows an exemplary aerial robot system with multiple measurement sources 101, where a first measurement source 5401 with a first field of view 5403 and a second measurement source 5402 with a second field of view 5404 extends the operating range of a single aerial robot 130. An exemplary non-contact measurement device 5115 end effector 131, is a displacement sensor 5116, that projects a displacement light beam 5117 onto a surface 5114, which is able to measure the distance to and the thickness of said surface.

[0105] FIG. 14 shows an exemplary measurement source 101 with a target camera and the ability to illuminate targets within the field of view 5301 of said measurement source. Targets must be rotated so that said measurement source is within the light acceptance angle of the targets 5302. Exemplary contact measurement device 5119 end effector 131 is a probe tip 5120.

[0106] FIG. 15 shows an exemplary end effector position mechanism 5501 coupled to the aerial robot mounting structure 5021. Said end effector position mechanism has a translation structure 5503 capable of horizontal motion 5505 and vertical motion 5506, or motion in orthogonal directions with respect to each other. Said end effector position mechanism also has a rotation structure 5502 capable of rotational motion 5504. A nozzle 5101 connected to this structure would have motion in up to five degrees of freedom with respect to said aerial robot mounting structure. The end effector command output 5507 from the aerial robot command processor will cause said nozzle to open and close as well as reposition. This configuration allows for faster correction to positional disturbances than are capable through the aerial robot propellers.

[0107] FIG. 16 shows an exemplary coordination processor 126 with a control algorithm 148 and with an action plan 132 read as an input action plan 5603 with one or more operation locations 5601 where the aerial robot must be positioned and end effector activator instructors 5602 are executed by the end effector.

[0108] FIG. 17 shows an exemplary motion control algorithm 148 executed by the coordination processor 126 that interacts with the control system plant 5704. Target data 127 from the measurement source 101 is transformed to the working coordinate system and is used as an input measured position 5705, which is compared to one or more operation locations 5601. A PI calculation generates an action output 128, which is instructs the aerial robot to adjust its position as an aerial robot command input 5702. The aerial robot command processor 5701 generates an output motor command 5703 causing the aerial robot to adjust its position.

[0109] FIG. 18 shows an exemplary light beam position measurement system 133 with a measurement source 101 that transmits an emitted measurement beam 102 toward a cooperative target 105 that is a single retro reflector 1102 reflecting back a reflected measurement beam 103. Said measurement source is capable of measuring the displacement of said emitted measurement beam from said reflected measurement beam. Said measurement source is capable of redirecting said emitted measurement beam so that it tracks the center of said retro reflector. The tracking angle and measured beam displacement combined with a measured distance to the target produce a target location 134 within the device coordinate system 104 defined by said measurement source, wherein the device coordinate system is a three-dimensional cartesian coordinate system; including three orthogonal axes, X, Y and Z as shown. The target locations in the device coordinate system will typically need to be transformed to locations in a working coordinate system.

[0110] FIG. 19 shows the front view of exemplary measurement source 101 with a combined measurement source light aperture 112 and source image aperture 114. An exemplary light beam 404 is an emitted measurement beam 102.

[0111] FIG. 20 shows an exemplary light beam position measurement system 133 with a measurement source 101, which is a laser tracker 303 with a beam steering assembly capable of moving the entire assembly to direct emitted measurement beam 102. An exemplary light receiving target 106 has a target light aperture 111 that is capable of reflecting a reflected measurement beam 103 as well as measuring rotations around the axes of a light receiving target coordinate system 107.

[0112] FIG. 21 shows an exemplary retro reflector 1102, which is a cooperative target 105.

[0113] FIG. 22 shows an exemplary partially transmissive retro reflector 1105, which is a cooperative target 105 capable of reflecting a portion of emitted measurement beam 102 as a reflected measurement beam 103 and transmitting the remaining portion as a transmitted measurement beam 1106.

[0114] FIG. 23 shows an exemplary retro sphere, which is a cooperative target 105.

[0115] FIG. 24 shows an exemplary light receiving target 106, which is a cooperative target 105 capable of measuring the orientation of the emitted measurement beam 102 within the target coordinate system 107. The orientation can be represented in a set of translations and rotations. Said light receiving target is also capable of reflecting a reflected measurement beam 103.

[0116] FIG. 25 shows an exemplary retro reflector assembly 1104, which is a cooperative target 105 with two or more retroreflectors 1107 mounted to a retro reflector mounting structure 1108. The measurement source measures each retroreflector 1102 and calculates a six degree of freedom orientation of the target coordination system 107.

[0117] FIG. 26 shows an exemplary aerial robot system where the measurement source 101 does not have a beam steering capability and therefor is mounted so that emitted measurement beam 102 is parallel to the X-axis of the working coordinate system 129. The robot and measurement devices will have local coordinate systems, which will require transformations to and from locations that are given with respect to the working coordinate system. It is possible to design a system where the different coordinate systems are aligned and therefore the same.

[0118] FIG. 27 shows an exemplary cooperative target 105, which is a camera-assisted target 5801, which may be also be referred to as a six degree of freedom (6DOF) target 5802. An emitted measurement beam 102 for which of portion is reflected back by said cooperative target as a reflected measurement beam 103. In addition, there are camera targets 5800, 5800′, 5800″, that are either reflective or light emitting. A camera combines the image of the camera targets with the position information from the measurement beam to create a six degree of freedom measurement.

[0119] It will be apparent to those skilled in the art that various modifications, combinations and variations can be made in the present invention without departing from the scope of the invention. Specific embodiments, features and elements described herein may be modified, and/or combined in any suitable manner. Thus, it is intended that the present invention cover the modifications, combinations and variations of this invention provided they come within the scope of the appended claims and their equivalents.

[0120] The following references are hereby incorporated by reference herein.

[0121] U.S. Pat. No. 4,790,651 Tracking Laser Interferometer, Brown et al.

[0122] U.S. Pat. No. 4,714,339 Three and Five Axis Laser Tracking Systems, Lau et al.

[0123] U.S. Pat. No. 7,510,142 Aerial Robot, Johnson.

[0124] U.S. Pat. No. 7,701,559 Absolute Distance Meter that Measures a Moving Retroreflector, Bridges, et al.

[0125] U.S. Pat. No. 8,525,983 Device and Method for Measuring Six Degrees of Freedom, Bridges et al.

[0126] U.S. Pat. No. 8,670,114 Device and Method for Measuring Six Degrees of Freedom, Bridges et al.

[0127] U.S. Pat. No. 8,803,055 Volumetric Error Compensation System with Laser Tracker and Active Target, Lau et al.

[0128] U.S. Pat. No. 9,164,506 Systems and Methods for Target Tracking, Zang

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[0130] U.S. Pat. No. 9,958,268 Three-Dimensional Measuring Method and Surveying System, Ohtomo et al.

[0131] U.S. Pat. No. 9,976,947 Position Measurement Device, Hoffer

[0132] European No. EP3140192A2 Aerial device capable of controlled flight and methods of using such a device, Kovac et al.

[0133] Japanese Pat. No. JP67844342 Methods, UAV Control Programs, Unmanned Aerial Vehicle Control Systems.