A method for calibrating a first coordinate system R f of a robot unit with a second coordinate system C f of an object identification unit, wherein the robot unit comprises a robot arm with an end effector and the object identification unit comprises a camera unit, the end effector further comprises a calibration marker, the method comprises - moving the end effector to a plurality of first target points wherein the first target points are chosen to include movement of the end effector in all three axes of the first coordinate system R f of the robot unit and wherein the end effector maintains a same orientation, while generating position measurements in the first coordinate system R f and position measurements in an image plane coordinate system IP f for the calibration marker with the object identification unit for each first target points; - calculating intrinsic parameters C int of the camera unit and a rotational part of the second coordinate system C f of the object identification unit based on the measurements in R f and IP f; - moving the end effector to a plurality of first orientations and for each of these orientations moving the end effector in a translation pattern while maintaining the same first orientation of the end effector and while generating position measurements in R f and IP f identifying the translation pattern; - calculating a depth value Z from the camera unit to the calibration marker for each second target point based on said position measurements identifying the movement along the translation pattern; - transforming position measurements in pixels in IP f to position values in the second coordinate system C f based on the depth value Z and C int; - calculating a translational part of the second coordinate system C f of the object identification unit based on the translation and reorientation between the first orientations; and - using the rotational and the translational parts to store a relation between R f and C f to enable collaboration between the robot unit and the object identification unit. - moving the end effector to a plurality of first target points wherein the first target points are chosen to include movement of the end effector in all three axes of the first coordinate system R f of the robot unit and wherein the end effector maintains a same orientation, while generating position measurements in the first coordinate system R f and position measurements in an image plane coordinate system IP f for the calibration marker with the object identification unit for each first target points; - calculating intrinsic parameters C int of the camera unit and a rotational part of the second coordinate system C f of the object identification unit based on the measurements in R f and IP f; - moving the end effector to a plurality of first orientations and for each of these orientations moving the end effector in a translation pattern while maintaining the same first orientation of the end effector and while generating position measurements in R f and IP f identifying the translation pattern; - calculating a depth value Z from the camera unit to the calibration marker for each second target point based on said position measurements identifying the movement along the translation pattern; - transforming position measurements in pixels in IP f to position values in the second coordinate system C f based on the depth value Z and C int; - calculating a translational part of the second coordinate system C f of the object identification unit based on the translation and reorientation between the first orientations; and - using the rotational and the translational parts to store a relation between R f and C f to enable collaboration between the robot unit and the object identification unit.