Abstract: A measurement system using heat compensation profiles for compensating inaccuracies caused by heat distortion is disclosed. Measurement of objects with different heat distribution involves use of heat compensation profiles with corresponding heat distribution. The heat compensation profile comprises a set of compensation coefficients that represent the deviation of the object having a heat distribution according to the heat compensation profile and the cooled down object. When the compensation coefficients are applied to the measured object the resulting measures correspond with the measurement results of the object after the object has been cooled.

Abstract: A machine vision system using a computer generated virtual reference object is disclosed. When the exact measures of the virtual reference object are known the machine vision system is capable of measuring differences on an absolute scale. In the machine vision system, a virtual reference object is produced based on computer drawings. The computer generated virtual reference object is further processed in order to achieve high photorealistic accuracy. The processing may involve combining portions from image of a manufactured object or computationally producing an image that looks like measured object. When the computer generated virtual reference object is based on the model drawing it does not include inaccuracies caused by manufacturing tolerances.

Abstract: A machine vision system capable of measuring differences on an absolute scale is disclosed. In the machine vision system, a reference object is accurately measured using a reference measurement arrangement, such as a coordinate measurement machine. In the measurement, a set of determined virtual points are measured. The reference measurement is used for computing a deviation matrix between a determined coordinate matrix and the reference measurement results that is later used for computing absolute scale values from machine vision measurements.

Abstract: A machine vision system using a computer generated virtual reference object is disclosed. When the exact measures of the virtual reference object are known the machine vision system is capable of measuring differences on an absolute scale. In the machine vision system, a virtual reference object is produced based on computer drawings. The computer generated virtual reference object is further processed in order to achieve high photorealistic accuracy. The processing may involve combining portions from image of a manufactured object or computationally producing an image that looks like measured object. When the computer generated virtual reference object is based on the model drawing it does not include inaccuracies caused by manufacturing tolerances.

Abstract: A method and a system for the quality control of objects after they have been supplied. After manufacturing, the object is checked by means of a measuring machine vision system. The measurement results of the machine vision system are recorded in a data system together with the corresponding calibration data. When the calibration data is known, new measurements can be conducted later from the recorded images at a time when the actual object has already been supplied and possibly placed in an end product.

Abstract: The present invention relates to a method and system for measuring articles made of a material that is difficult to measure, such as glass. In the system, an elastic film (19) is arranged on top of an article (110). A number of measurement points have been arranged on the film that are imaged using a machine vision system. The location of the measurement points imaged are calculated with respect to one another, and based on this, the shape of the article can be measured.

Abstract: The invention relates to a method and system for determining the direction and location of the symmetry axis of a revolution-shaped article. Furthermore, the invention enables one to determine the radius of the article as well as the pitch of a possible thread. In the arrangement of the invention, the article being measured is illuminated using light sources arranged in direct vicinity of the cameras. Each camera is measuring the reflection plane formed from the article being measured based on the light reflected backward from the article. The symmetry axis is determined by calculating the transversal of the reflection planes. The system of the invention uses at least two cameras, but the measurement accuracy can be improved by calculating the symmetry axis from the transversals of the reflection planes of a bigger set of cameras. Furthermore, at least a third camera is required to calculate the pitch of thread.

Abstract: The present invention relates to a method and system for measuring articles made of a material that is difficult to measure, such as glass. In the system, an elastic film (19) is arranged on top of an article (110). A number of measurement points that are imaged using a machine vision system. The location of the measurement points imaged are calculated with respect to one another, and based on this, the shape of the article can be measured.