Calibration device

Patent metadata

Field	Value
Publication number	US-2022050189-A1
Application number	US-202017018453-A
Country	US
Kind code	A1
Filing date	Sep 11, 2020
Priority date	Aug 12, 2020
Publication date	Feb 17, 2022
Grant date	—

Abstract

A calibration device includes a base, a support column coupled to the base and extending in a first direction, and a crossbar coupled to the support column. The crossbar includes a positioning base and a carrier. The positioning base is fixed to the support column. The carrier is coupled to the positioning base and rotatable about a second direction perpendicular to the first direction. The carrier includes a distance sensor and a calibration platform. The calibration platform mounts a depth camera. The carrier is configured to rotate about the second direction to rotate an optical axis of the depth camera in a first calibration plane defined by the first direction and a third direction. The third direction is perpendicular to the first direction and the second direction.

First claim

What is claimed is:

1 . A calibration device comprising:
a base; a support column coupled to the base, the support column extending in a first direction; and a crossbar coupled to the support column; wherein: the crossbar comprises a positioning base and a carrier; the positioning base is fixed to the support column; the carrier is coupled to the positioning base and rotatable about a second direction perpendicular to the first direction; the carrier comprises a distance sensor and a calibration platform; the calibration platform mounts a depth camera; the carrier is configured to rotate about the second direction to rotate an optical axis of the depth camera in a first calibration plane defined by the first direction and a third direction; and the third direction is perpendicular to the first direction and the second direction.

2 . The calibration device of claim 1 , wherein:
the support column is coupled to the base and rotatable about the first direction; and the support column is configured to rotate about the first direction to rotate the optical axis of the depth camera in a second calibration plane defined by the second direction and the third direction.

3 . The calibration device of claim 2 , wherein:
the crossbar comprises a driver; and the driver is configured to rotate the distance sensor and/or the calibration platform about the second direction.

4 . The calibration device of claim 3 , wherein:
the positioning base comprises a first mounting plate and two first side plates arranged respectively on two sides of the first mounting plate; the first mounting plate and the two side plates cooperatively surround a holding space for receiving the carrier; and the driver is fixedly mounted on an outer side of one of the first side plates.

5 . The calibration device of claim 4 , wherein:
the carrier comprises a rotating base; the distance sensor and the calibration platform are fixedly mounted on the rotating base; and the rotating base is received in the holding space and rotatable about the second direction.

6 . The calibration device of claim 5 , wherein:
the rotating base comprises a second mounting plate, a second slide plate, and a third side plate; the distance sensor and the calibration platform are mounted on the third surface, and the distance sensor is located between the calibration platform and the second side plate; the second side plate is rotationally coupled to the driver by a first rotating shaft; the calibration platform is rotationally coupled to the first side plate by a second rotating shaft; and the second rotating shaft and the first rotating shaft extend along the second direction.

7 . The calibration device of claim 6 , wherein:
the calibration platform is detachably coupled to the third side plate.

8 . The calibration device of claim 3 , wherein:
the base body is made of an anti-vibration elastic material.

9 . A calibration method for a depth camera, the calibration method comprising:
mounting the depth camera on a calibration platform of a calibration device, and adjusting an optical axis of the depth camera to face a calibration surface; when the depth camera is located at a first position, a distance sensor mounted with the calibration platform sensing a first distance between the depth camera and the calibration surface; rotating the distance sensor and the calibration platform about a second direction by a first preset angle, so that the depth camera rotates from the first position to a second position, and the distance sensor senses a second distance between the depth camera and the calibration surface; calculating a first deviation angle between the calibration surface and a first direction perpendicular to the second direction according to the first preset angle, the first distance, and the second distance; calculating a first compensation angle according to the first deviation angle and the first preset angle; and rotating the calibration platform and the distance sensor about a third direction perpendicular to the first direction and the second direction from the second position by the first compensation angle to a third position, wherein in the third position, the optical axis of the depth camera is perpendicular to an intersection line of a first calibration plane and the calibration surface α, the first calibration plane defined by the first direction and the third direction.

10 . The calibration method of claim 9 , further comprising:
sensing, by the distance sensor, a third distance between the depth camera and the calibration surface when the depth camera and the calibration platform are at a fourth position; rotating the support column about the first direction by a second preset angle until the depth camera reaches a fifth position, and then the distance sensor sensing a fourth distance between the depth camera and the calibration surface; calculating a second deviation angle between the calibration surface and the second direction according to the second preset angle, the third distance, and the fourth distance; calculating a second compensation angle according to the second deviation angle and the second preset angle; and rotating the support column about the first direction by the second compensation angle so that the depth camera is rotated from the fifth position to a sixth position, wherein the optical axis of the depth camera is perpendicular to the calibration surface at the sixth position.

11 . The calibration method of claim 10 , wherein:
the first deviation angle γ is calculated according to the formula:

γ
=

90
⁢
°

-

arcsin
(

L
⁢

⁢
1
⁢
sin
⁢

⁢
β

(

L
⁢

⁢

1
2

+

L
⁢

⁢

2
2

-

2
⁢

⁢
L
⁢

Assignees

• Triple Win Tech Shenzhen Co Ltd

Inventors

• Zhang xiao-fang
• Lin Yen-Sheng

Classifications

• G01S7/481

  Constructional features, e.g. arrangements of optical elements · CPC title

• F16M11/2014

  around a vertical axis (F16M11/2035 takes precedence) · CPC title

• F16M11/18

  with mechanism for moving the apparatus relatively to the stand · CPC title

• F16M11/10

  around a horizontal axis {(F16M11/12 takes precedence)} · CPC title

• G01S7/497 Primary

  Means for monitoring or calibrating · CPC title