Method for ascertaining at least one degree of freedom of a camera, computer program, machine-readable storage medium, and electronic control unit or automation assembly

A method for ascertaining at least one degree of freedom of a camera relative to a code arrangement from a camera image of the camera, the code arrangement has a point grid with a plurality of base symbols, wherein a coarse position of the base symbols is encoded in the code arrangement, wherein the base symbols define a first main direction, and a second main direction independent of the first main direction, along the point grid, wherein wherein a reference point is arranged in the camera image, wherein the reference point is formed as an intersection point of an optical axis of the camera with the image sensor and/or the camera image, the method comprising the following steps:

• determining the following values as characteristic values from the camera image at the reference point:
• an angle of rotation of the camera about the optical axis of the camera,
• a first local grid spacing of the point grid in the camera image in the first main direction and/or a second local grid spacing of the point grid in the camera image in the second main direction,
• a first local angular divergence of the point grid in the camera image in the first main direction, wherein the first local angular divergence describes a difference angle between two adjacent straight lines in the first main direction in the point grid, and
• a second local angular divergence of the point grid in the camera image in the second main direction, wherein the second local angular divergence describes the difference angle between two adjacent straight lines in the second main direction in the point grid;
• determining, based on the characteristic values, the following three degrees of freedom of the camera relative to the code arrangement:
• a distance between the code arrangement and the camera, and
• two independent pitch angles of the optical axis to the code arrangement.

An electronic control unit or automation assembly having the electronic control unit, wherein the control unit comprises programming and/or circuitry to carry out a method for ascertaining at least one degree of freedom of a camera relative to a code arrangement from a camera image of the camera, the code arrangement has a point grid with a plurality of base symbols, wherein a coarse position of the base symbols is encoded in the code arrangement, wherein the base symbols define a first main direction, and a second main direction independent of the first main direction, along the point grid, wherein a reference point is arranged in the camera image, wherein the reference point is formed as an intersection point of an optical axis of the camera with the image sensor and/or the camera image, the method including the following steps:

• determining the following values as characteristic values from the camera image at the reference point:
• an angle of rotation of the camera about the optical axis of the camera,
• a first local grid spacing of the point grid in the camera image in the first main direction and/or a second local grid spacing of the point grid in the camera image in the second main direction,
• a first local angular divergence of the point grid in the camera image in the first main direction, wherein the first local angular divergence describes a difference angle between two adjacent straight lines in the first main direction in the point grid, and
• a second local angular divergence of the point grid in the camera image in the second main direction, wherein the second local angular divergence describes the difference angle between two adjacent straight lines in the second main direction in the point grid;
• determining, based on the characteristic values, the following three degrees of freedom of the camera relative to the code arrangement:
• a distance between the code arrangement and the camera, and
• two independent pitch angles of the optical axis to the code arrangement.

A non-transitory machine-readable storage medium on which is stored a computer program for ascertaining at least one degree of freedom of a camera relative to a code arrangement from a camera image of the camera, the code arrangement has a point grid with a plurality of base symbols, wherein a coarse position of the base symbols is encoded in the code arrangement, wherein the base symbols define a first main direction, and a second main direction independent of the first main direction, along the point grid, wherein wherein a reference point is arranged in the camera image, wherein the reference point is formed as an intersection point of an optical axis of the camera with the image sensor and/or the camera image, the computer program, when executed by a computer, causing the computer to perform the following steps:

• determining the following values as characteristic values from the camera image at the reference point:
• an angle of rotation of the camera about the optical axis of the camera,
• a first local grid spacing of the point grid in the camera image in the first main direction and/or a second local grid spacing of the point grid in the camera image in the second main direction,
• a first local angular divergence of the point grid in the camera image in the first main direction, wherein the first local angular divergence describes a difference angle between two adjacent straight lines in the first main direction in the point grid, and
• a second local angular divergence of the point grid in the camera image in the second main direction, wherein the second local angular divergence describes the difference angle between two adjacent straight lines in the second main direction in the point grid;
• determining, based on the characteristic values, the following three degrees of freedom of the camera relative to the code arrangement:
• a distance between the code arrangement and the camera, and
• two independent pitch angles of the optical axis to the code arrangement.