EP-4739465-A1 - METHOD AND SYSTEM FOR CALIBRATION USING A TOUCH SCREEN

EP4739465A1EP 4739465 A1EP4739465 A1EP 4739465A1EP-4739465-A1

Abstract

Embodiments of the present disclosure relate to a method and a system for calibrating peripheral devices associated with an industrial robot using a touch screen. The method comprises: obtaining, in response to a touch component (14) touching at least three points being not collinear on the touch screen (30) when a conveyor (20) is at a first position, a first set of coordinates of the at least three points in a robot coordinate system and a second set of coordinates of the at least three points in a touch screen coordinate system; causing the conveyor (20) to move from the first position to a second position different from the first position; obtaining, in response to the touch component (14) touching at least further three points being not collinear on the touch screen (30) when the conveyor (20) is at the second first position, a third set of coordinates of the at least further three points in the robot coordinate system and a fourth set of coordinates of the at least three further points in the touch screen coordinate system; and determining a conveyor coordinate of the conveyor in the robot coordinate system based on the first set of coordinates, the second set of coordinates, the third set of coordinates and the fourth set of coordinates.

Inventors

CHANG, KUN
GU, HAO
MAO, LEI
QIAN, Changnian
MA, JING

Assignees

ABB SCHWEIZ AG

Dates

Publication Date: 20260513
Application Date: 20230707

Claims (15)

A method for calibration using a touch screen (30) , comprising: obtaining, in response to a touch component (14) touching at least three points being not collinear on the touch screen (30) when a conveyor (20) is at a first position, a first set of coordinates of the at least three points in a robot coordinate system and a second set of coordinates of the at least three points in a touch screen coordinate system, the touch component (14) being mounted on a manipulator (12) of an industrial robot (10) , and the touch screen (30) being placed on the conveyor (20) and stationary with respect to the conveyor (20) ; causing the conveyor (20) to move from the first position to a second position different from the first position; obtaining, in response to the touch component (14) touching at least further three points being not collinear on the touch screen (30) when the conveyor (20) is at the second first position, a third set of coordinates of the at least further three points in the robot coordinate system and a fourth set of coordinates of the at least three further points in the touch screen coordinate system; and determining a conveyor coordinate of the conveyor in the robot coordinate system based on the first set of coordinates, the second set of coordinates, the third set of coordinates and the fourth set of coordinates.
The method of claim 1, further comprising: obtaining a first value from an encoder (22) of the conveyor (20) when the conveyor (20) is at the first position; obtaining a second value from the encoder (22) when the conveyor (20) is at the second position; obtaining third values from an acceleration sensor and a gyroscope of the touch screen (30) during movement of the conveyor (20) from the first position to the second position; determining, based on the third values, a moving direction and a moving distance of the touch screen (30) during movement of the conveyor (20) from the first position to the second position; and determining, based on the first value, the second value, and the determined moving direction and the moving distance of the touch screen (30) , a relationship between a count of the encoder (22) and the movement of the conveyor (20) .
The method of any of the preceding claims, wherein the touch component (14) touching the at least three points when the conveyor (20) is at the first position comprises causing the manipulator (12) to move in response to a teaching input from a user to cause the touch component (14) to touch the at least three points on the touch screen (30) .
The method of claim 2, further comprising: determining, based on the moving direction and the moving distance, a first coordinate of the touch screen (30) in the robot coordinate system when the conveyor (20) is at the second position; and causing, based on the determined first coordinate of the touch screen (30) , the manipulator (12) to move without a teaching input from a user to cause the touch component (14) to touch the at least further three points on the touch screen (30) .
The method of any of claims 2-4, further comprising determining, based on at least one of the moving direction and the moving distance, whether the conveyor (20) is a linear conveyor or a circular conveyor.
The method of any of the preceding claims, wherein the at least three points and/or the at least further three points are arbitrary points on the touch screen (30) that are not collinear.
The method of any of the preceding claims, further comprising causing the touch screen (30) to display a checkerboard pattern; causing a camera (50) to capture an image of the touch screen (30) displaying the checkerboard pattern, the camera (50) being mounted above the conveyor (20) ; and determining, based on the captured image, a position relationship between the camera (50) and the touch screen (30) .
The method of claim 7, further comprising: determining, based on the first and second sets of coordinates or the third and fourth sets of coordinates, a second coordinate of the touch screen (30) in the robot coordinate system; and determining, based on the position relationship and the determined second coordinate, a camera coordinate of the camera in the robot coordinate system.
The method of claim 8, further comprising: (a) causing the touch screen (30) to display an object (32) to be touched at a predetermined position in the touch screen (30) ; (b) causing the camera (50) to capture an image of the touch screen (30) displaying the object (32) to be touched; (c) determining, based on the captured image, a third coordinate of the object (32) in the robot coordinate system; (d) causing the manipulator (12) to move to cause the touch component (14) to touch the object (32) in the touch screen (30) based on the third coordinate; and (e) obtaining, in response to the touch component (14) touching the object (32) in the touch screen (30) , a fourth coordinate of the touched point in the camera coordinate system.
The method of claim 9, further comprising: causing the touch screen (30) to sequentially display a plurality of objects (32) to be touched in a predetermined time sequence; for each object (32) to be touched, repeating the steps (a) - (e) to obtain a plurality of the touched points at which the touch component (14) touches the touch screen (30) ; and outputting the plurality of the touched points for analyzing a performance of at least one of the camera (50) and the manipulator (12) .
The method of any of claims 9-10, further comprising obtaining, from the touch screen (30) , time information that the touch component (14) touches the object (32) in the touch screen (30) ; and outputting the time information for analyzing a performance of at least one of the manipulator (12) and the conveyor (20) .
The method of any of the preceding claims, further comprising obtaining, in response to a second touch component (14) touching at least three points being not collinear on the touch screen (30) when the conveyor (20) is at a third position different from the first position and the second position, a fifth set of coordinates of the at least three points in a second robot coordinate system and a sixth set of coordinates of the at least three points in the touch screen coordinate system, the second touch component (14) being mounted on a second manipulator (12) of a second industrial robot (10) ; and determining a second conveyor coordinate of the conveyor in the second robot coordinate system based on the fifth set of coordinates and the sixth set of coordinates.
The method of any of the preceding claims, further comprising causing the touch screen (30) to display a checkerboard pattern when the touch screen is located near a second camera (50) being mounted above the conveyor (20) ; causing the second camera (50) to capture an image of the touch screen (30) displaying the checkerboard pattern; determining, based on the captured image, a second position relationship between the second camera (50) and the touch screen (30) .
A system for calibration, comprising: a touch screen (30) placed on a conveyor (20) associated with at least one industrial robot (10) and stationary with respect to the conveyor (20) ; and a controller (40) communicatively connected to the touch screen (30) and the at least one industrial robot (10) , the controller (40) being configured to: obtain, in response to a touch component (14) mounted on a manipulator (12) of the at least one industrial robot (10) touching at least three points being not collinear on the touch screen (30) when the conveyor (20) is at a first position, a first set of coordinates of the at least three points in a robot coordinate system and a second set of coordinates of the at least three points in a touch screen coordinate system; cause the conveyor (20) to move from the first position to a second position different from the first position; obtain, in response to the touch component (14) touching at least further three points being not collinear on the touch screen (30) when the conveyor (20) is at the second first position, a third set of coordinates of the at least further three points in the robot coordinate system and a fourth set of coordinates of the at least three further points in the touch screen coordinate system; and determine a conveyor coordinate of the conveyor in the robot coordinate system based on the first set of coordinates, the second set of coordinates, the third set of coordinates and the fourth set of coordinates.
A computer program product comprising a computer program thereon, the computer program, when executed by a processor, caused to implement a method according to any of claims 1-13.

Description

METHOD AND SYSTEM FOR CALIBRATION USING A TOUCH SCREEN FIELD Embodiments of the present disclosure generally relate to calibrating peripheral devices for an industrial robot and in particular to a method and a system for calibrating peripheral devices for an industrial robot using a touch screen. BACKGROUND With repaid development of industrial automation, industrial robots are widely and increased used in an industrial field. More and more peripheral devices, such as conveyors, cameras, and the like, are used to cooperate with the industrial robot so as to enhance performances of the industrial robot. Before these peripheral devices are put into use, these peripheral devices have to be calibrated so that the industrial robot can identify and locate these devices. Thus, the industrial robot can precisely and synchronically cooperate with these peripheral devices to perform various tasks in the industrial field. However, calibrating these peripheral devices is typically complex, tedious and operator-dependent. Conventional calibration methods are subject to the following drawbacks. Different peripheral device requires different calibration methods. Even though a calibration manual or specification is provided for each peripheral device, there is no uniform method that is configured to calibrate multiple peripheral devices. Also, most calibration methods still require participation of professional personnel, which is inconvenient for a customer, who lacks the professional knowledge for calibration, resulting in increased costs. Another disadvantage is that calibration methods more or less need manual intervention. This results that the calibration results are highly operator-dependent and are prone to human errors. There is a need to improve conventional calibration method. SUMMARY Example embodiments of the present disclosure provide a method and a system for calibrating peripheral devices associated with an industrial robot using a touch screen which can obviate or mitigate at least one of the above mentioned problems. In a first aspect of the present disclosure, there is provided a method for calibration using a touch screen. The method comprises: obtaining, in response to a touch component touching at least three points being not collinear on a touch screen when a conveyor associated with an industrial robot is at a first position, a first set of coordinates of the at least three points in a robot coordinate system and a second set of coordinates of the at least three points in a touch screen coordinate system, the touch component being mounted on a manipulator of the industrial robot, and the touch screen being placed on the conveyor and stationary with respect to the conveyor; causing the conveyor to move from the first position to a second position different from the first position; obtaining, in response to the touch component touching at least further three points being not collinear on the touch screen when the conveyor is at the second first position, a third set of coordinates of the at least further three points in the robot coordinate system and a fourth set of coordinates of the at least three further points in the touch screen coordinate system; and determining a conveyor coordinate of the conveyor in the robot coordinate system based on the first set of coordinates, the second set of coordinates, the third set of coordinates and the fourth set of coordinates. With this method, by using the touch screen which can record the touching points in its own touch screen coordinate system, processes for calibrating the conveyor can be simplified. In some embodiments, the method may further comprise: obtaining a first value from an encoder of the conveyor when the conveyor is at the first position; obtaining a second value from the encoder when the conveyor is at the second position; obtaining third values from an acceleration sensor and a gyroscope of the touch screen during movement of the conveyor from the first position to the second position; determining, based on the third values, a moving direction and a moving distance of the touch screen during movement of the conveyor from the first position to the second position; determining, based on the first value, the second value, and the determined moving direction and the moving distance of the touch screen, a relationship between a count of the encoder and the movement of the conveyor. With this method, by using the acceleration sensor and the gyroscope of the touch screen, the rough moving direction and the rough moving distance of the touch screen can be determined. Thus, the encoder of the conveyor can be automatically calibrated. In some embodiments, the touch component touching the at least three points when the conveyor is at the first position comprises causing the manipulator to move in response to a teaching input from a user to cause the touch component to touch the at least three points on the touch screen. With this method, the