Metrology system
The invention relates generally to a metrology system and coordinate measuring devices to be used within the framework of a smart factory environment, which has a defined arrangement of different metrology devices, configured such that coordinate measuring data generated by different metrology devices are referencable to a common coordinate system.
1 . A metrology system comprising:
a laser tracker having:
an opto-electronic distance meter configured to emit a distance measurement beam towards a cooperative target of a moveable accessory device in the direction of an aiming axis, and to provide distance measurement data based on at least a part of the distance measurement beam returning from the cooperative target, wherein the cooperative target is configured to cooperate with a tracking unit of the laser tracker to generate a tracking signal,
an angle determining unit configured to provide angle determination data for determining the pointing direction of the aiming axis, and
the tracking unit configured
to receive over a tracking channel the tracking signal which is indicative of a change in angular location of the cooperative target,
to determine the change in angular location of the cooperative target based on the tracking signal, and
to generate control data for adjusting an alignment of the aiming axis based on the determined change in angular location,
the movable accessory device, configured for scanning or probing of an object, and
a computing unit configured to generate coordinate measuring data for the object by using the distance measuring data and the angle determination data to determine a position of the movable accessory device, and by using the determined position of the movable accessory device for referencing the scanning and/or probing by means of the movable accessory device to a coordinate system relative to the laser tracker, and
a referencing unit configured to determine a positional change between the referencing unit and a reference point on the object to detect a movement of the object in at least one degree of freedom, wherein:
the referencing unit is provided by the laser tracker or by a separate device which is different from the movable accessory device, wherein the separate device and the laser tracker are configured such that the referencing data are referenceable to the coordinate measuring data,
the positional change is determined by referencing data generated by the referencing unit independently from the opto-electronic distance meter, the reference point is embodied by a cooperative target mounted on the object or defined by a reference surface of the object, and
the computing unit is configured to take into account the referencing data to generate the coordinate measuring data.
2 . The system according to claim 1 , wherein the referencing unit is embodied as a camera unit being configured to generate 3 D data of the object based on imaging data.
3 . The system according to claim 2 , wherein the camera unit comprises
a projector configured to project a pattern of structured radiation onto the object, and
a processor configured to determine a 3D model of the object based on a photogrammetric method and by making use of the pattern of structured radiation.
4 . The system according to claim 1 , wherein the referencing unit is configured to detect a vibration of the object.
5 . The system according to claim 1 , wherein the referencing unit is configured to detect at least one of a change in roll, a change in pitch, and a change in yaw angle of the object.
6 . The system according to claim 1 , wherein the computing unit is configured to generate the coordinate measuring data by at least one of
compensating a movement of the object determined based on the referencing data,
ignoring distance measuring data of the opto-electronic distance meter and/or angle determination data of the angle determining unit in case a relative positional change between the object and the referencing unit exceeds an allowed threshold, and
flagging the coordinate measuring data in case a relative positional change between the object and the referencing unit exceeds a threshold defined for ensuring a desired measurement accuracy of the coordinate measuring data.
7 . The system according to claim 1 , wherein the movable accessory device is at least one of
a probing or scanning device configured to approach the object and to carry out at least one of a tactile, a laser based, and a camera based coordinate measurement, particularly embodied as a range imaging camera, a stereo-imaging camera, an articulated arm robot, or a white light sensor,
a marking device configured to mark the object,
a tool and/or manufacturing instrument, and
another laser tracker.
8 . The system according to claim 1 , wherein the referencing unit configured and arranged that the referencing data are referenceable to the coordinate measuring data.
9 . The system according to claim 1 , wherein the tracking unit comprises a tracking sensor and is configured to generate a tracking beam and to receive the tracking signal based on the tracking beam returning from the cooperative target, by determining a deviation from a zero position on the tracking sensor.