Method and system for highly precisely positioning at least one object in an end position in space

A system for highly precisely positioning at least one object in an end position in space by means of an industrial robot, comprising:

• a first industrial robot, which is adjustable into predeterminable positions;
• an optical 3D image recording device, which is calibrated in a three-dimensional spatial coordinate system and is positioned in a known position with a known alignment, is designed for electronically recording three-dimensional images within a specific field of view, wherein the three-dimensional images are in each case composed of a multiplicity of pixels which are each assigned an item of depth information, has a drive unit for the alignment, which brings about adjustment of the field of view—of the 3D image recording device, and has an angle measuring unit calibrated in the spatial coordinate system and serving for highly precisely detecting the angular alignment of the 3D image recording device, such that it is possible to determine the field of view in the spatial coordinate system;
• and
• a control apparatus, which has a data processing device designed for image processing, wherein the control apparatus has a data connection to the first industrial robot and the optical 3D image recording device in such a way that:
• the three-dimensional images recorded by the optical 3D image recording device are fed to the control apparatus;
• the angular alignment of the 3D image recording device, said angular alignment being detected by the angle measuring unit, is fed to the control apparatus;
• the drive unit is driven for aligning the 3D image recording device by means of the control apparatus;
• and
• the first industrial robot is adjusted in positions that are predetermined by the control apparatus,
• wherein the control apparatus and the data processing device thereof are designed in such a way that:
• a first object, which has optically detectable first features known to the control apparatus, is gripped and held by the first industrial robot within a gripping tolerance;
• a first compensation variable, correcting the gripping tolerance, for the first industrial robot is determined by the control apparatus such that the first object is adjustable in a compensated fashion in the spatial coordinate system by predetermining a position of the first industrial robot, wherein the first compensation variable is determined by means of the control apparatus by the steps of:
• aligning the field of view of the 3D image recording device by means of the drive unit with at least one portion of the first features of the first object held in a first compensation position of the first industrial robot;
• recording at least one first three-dimensional image;
• determining the position of the first object in the spatial coordinate system in the first compensation position of the first industrial robot from the position of the 3D image recording device, the angular alignment of the 3D image recording device, said angular alignment being detected by the angle measuring unit, the first three-dimensional image, and the knowledge of the first features on the first object;
• and
• determining the first compensation variable by utilizing the first compensation position of the first industrial robot, and at least the determined position of the first object in the first compensation position of the first industrial robot, and
• the first object is highly precisely adjusted by the control apparatus to a first end position by the following steps, which are repeated until the first end position is reached in a predetermined tolerance:
• recording at least one further first three-dimensional image;
• determining the present position of the first object in the spatial coordinate system from:
• the position of the 3D image recording device;
• the angular alignment of the 3D image recording device, said angular alignment being detected by the angle measuring unit;
• the further first three-dimensional image;
• and
• the knowledge of the first features on the first object;
• calculating the position difference between the present position of the first object and the first end position;
• calculating a new desired position of the first industrial robot taking account of the first compensation variable from the present position of the first industrial robot, and a variable which is linked to the position difference and is formed, in particular, by the position difference multiplied by a factor of less than or equal to 1;
• and
• adjusting the first industrial robot to the new desired position.