Calibration methods The conversion of image coordinates into world coordinates
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Calibration methods The conversion of image coordinates into world coordinates Vision sensors Optical sensors Ultrasonic sensors Inductive sensors

Calibration methods The conversion of image coordinates into world coordinates The calibration of robots serves to enable the conversion of image coordinates into world coordinates. As a result, all coordinate outputs (positions and measurement results) are calculated and output in the selected unit. There are various calibration methods for applications in the field of robotics. These include: ▪ Calibration plate ▪ Point pair list ▪ Hand-Eye Calibration ▪ Base-Eye Calibration The robot calibrations first convert pixels into metric or imperial units and correct distortions and tilted...

Goals of calibration - why is calibration important? ▪ etermining the reference system: Calibration is used to determine the reference between the camera coordinate system and D the robot base (position and orientation). ▪ ixel measurement unit conversion: Calibration enables the conversion of pixels into a measurement unit, which is needed to P determine the exact position of objects in the field of view of the vision sensor. ▪ istortion correction: The calibration also enables the correction of distortions caused by the optics of the vision sensor. D ▪ ilt correction: Calibration also...

Calibration plate Camera mounted on arm or stationary The Method: With this calibration method, the absolute positions in the robot coordinate system are determined by means of a "calibration plate". The user can determine the position of the plate in space via applied reference marks with the help of a measuring tip. To do this, one or more images of the calibration plate are taken and four reference marks are taught in. The coordinate values determined in this way are then entered into the VISOR® configuration software. This teach-in process transforms the image coordinates of the sensor...

Point pair list Camera mounted stationary The Method: The calibration method "point pair list" is a calibration on the work object and thus does not require a calibration plate. Real components are placed in the field of view of the VISOR® and the component coordinates in the image (px) are determined and linked to a corresponding position in the robot coordinate system ("world"). The calibration can be calculated using several of these point pairs. After the calibration of the sensor, the position of the part to be gripped by the robot is directly available in the absolute coordinate...

Hand-eye calibration Camera mounted on arm The Method: Hand-eye calibration" is an effective method to calibrate sensors mounted on the robot arm, such as in automated gripping or screwing of objects. A major advantage of this method is that in applications with a camera mounted on the robot arm, this flexibility can be used to move the workspace in the robot workspace. This results in a high degree of flexibility. To make the most of this advantage, special functions such as "Trigger Robotic" are available to inform the VISOR® of the changed position. All calculations are then carried out...

Base-Eye calibration Camera mounted stationary The Method: SensoPart's base-eye calibration is a calibration method that is particularly suitable for applications in which the vision sensor is mounted in a stationary position - for example, when fine positioning components in the gripper. In contrast to classical calibration methods, it is no longer necessary to manually approach real points or to grip components. To map the complete coordinate system, it is sufficient to take at least ten images of the calibration plate in different positions. If required, an additional "result offset" is...

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