Calibration of a camera provided for monitoring an additive manufacturing process

Abstract

The invention relates to a method for the calibration of a camera (20), wherein the camera (20) is provided for monitoring additive manufacturing of an object in which material (12) is applied in a plurality of layers. The method comprises the following steps: a) providing the camera (20) and providing means for additive manufacturing of the object, b) capturing an image (21) of the object being manufactured or already manufactured by means of the camera (20), c) comparing the image (21) captured with a model (40) of the object, d) determining a calibration function on the basis of the comparison from step c), which is intended to transform the image (21) captured into a corrected image, wherein the corrected image of the object substantially corresponds to the model (40) of the object, and e) calibrating the camera (20) by means of the calibration function. The invention further relates to a computer program comprising commands which, when the program is executed by a computer, cause the computer to execute the steps of the said method. Finally, the invention relates to an apparatus comprising means for performing additive manufacturing of an object, a camera (20) provided for monitoring the additive manufacturing process and a calibration unit (30) for calibrating the camera (20).

Description

technical field [0001] The invention relates to a method for calibrating a camera provided for monitoring an additive manufacturing process. The invention also relates to a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the steps of the proposed method. Finally, the invention relates to a device comprising a mechanism for performing additive manufacturing of objects, a camera arranged for monitoring the additive manufacturing process and a calibration unit for calibrating the camera. Background technique [0002] Monitoring of additive manufacturing methods is important so that any deviations in the process are identified early and the quality of the manufactured objects can be guaranteed. To monitor additive manufacturing methods, cameras that record and store images during the manufacturing process are typically used. [0003] When recording images, perspective distortion and geometric imaging e...

AI Technical Summary

Problems solved by technology

[0008] The disadvantage of the calibration method described is that it is relatively complex to carry out

Calibration takes time and can usually only be performed by trained personnel as the calibration plate must be positioned very carefully at the preset location

Furthermore, the production run had to be interrupted for this; therefore, the 3D printer was not available during the time the calibration method was performed

[0009] Another disadvantage of the calibration method based on the calibration plate is that the user must have the calibration plate

[0011] The disadvantage of this calibration method is that not every 3D printed device has this easily reidentifiable and immovable facility-specific point

During the application of the powdered material, any reference markings that may be present are usually covered up, so that a reliable and precise identification of the reference markings cannot be guaranteed.

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