Axial deviation estimating device

An axial misalignment estimation apparatus that is mounted in a moving body, the axial misalignment estimation apparatus comprising:

• a processor;
• a non-transitory computer-readable storage medium;
• and
• a set of computer-executable instructions stored on the computer-readable storage medium that when read and executed by the processor, that cause the processor to implement:
• acquiring, for each of a plurality of reflection points that are detected by a radar apparatus, reflection point information that includes at least a horizontal angle and a vertical angle that are an orientation angle of the reflection point and determined with reference to a beam direction that is a direction along a center axis of a radar beam, and a distance between the radar apparatus and the reflection point;
• extracting, from the plurality of reflection points, a plurality of road-surface reflection points that are detected by reflection on a road surface based on at least the reflection point information;
• calculating a road-surface flatness level that is a numeric value that indicates a degree of flatness of the road surface;
• determining whether the road surface is flat based on the road-surface flatness level;
• identifying, for each road-surface reflection point, apparatus system coordinates that are three-dimensional coordinates that are based on coordinate axes of the radar apparatus based on the reflection point information;
• and
• estimating an axial misalignment angle of the radar apparatus and a height of the radar apparatus using a relational expression that is established between at least two unknown parameters and at least two elements,
• the at least two unknown parameters including the axial misalignment angle that is a misalignment angle of a coordinate axis of the radar apparatus around a target axis that is one of a horizontal axis and a moving-direction axis that are coordinate axes of the moving body, and a mounting height of the radar apparatus, and
• the at least two elements being included in the apparatus system coordinates of the road-surface reflection point, wherein:
• estimating the axial misalignment angle and the height of the radar apparatus includes
• performing weighting based on the road-surface flatness level using the relational expression and estimating the axial misalignment angle of the radar apparatus and the mounting height of the radar apparatus, in response to determining that the road surface is not flat, and
• adjusting, by an adjustment apparatus mounted to the radar apparatus, a mounting angle of the radar apparatus of the radar apparatus and the mounting height of the radar apparatus, based on the estimated axial misalignment angle of the radar apparatus and the estimated height of the radar apparatus.

An axial misalignment estimation method for a moving body, the axial misalignment estimation method comprising:

• acquiring, for each of a plurality of reflection points that are detected by a radar apparatus, reflection point information that includes at least a horizontal angle and a vertical angle that are an orientation angle of the reflection point and determined with reference to a beam direction that is a direction along a center axis of a radar beam, and a distance between the radar apparatus and the reflection point;
• extracting, from the plurality of reflection points, a plurality of road-surface reflection points that are detected by reflection on a road surface based on at least the reflection point information;
• calculating a road-surface flatness level that is a numeric value that indicates a degree of flatness of the road surface;
• determining whether the road surface is flat based on the road-surface flatness level;
• identifying, for each road-surface reflection point, apparatus system coordinates that are three-dimensional coordinates that are based on coordinate axes of the radar apparatus based on the reflection point information;
• and
• estimating an axial misalignment angle of the radar apparatus and a height of the radar apparatus using a relational expression that is established between at least two unknown parameters and at least two elements,
• the at least two unknown parameters including the axial misalignment angle that is a misalignment angle of a coordinate axis of the radar apparatus around a target axis that is one of a horizontal axis and a moving-direction axis that are coordinate axes of the moving body, and a mounting height of the radar apparatus, and
• the at least two elements being included in the apparatus system coordinates of the road-surface reflection point, wherein:
• estimating the axial misalignment angle and the height of the radar apparatus includes
• performing weighting based on the road-surface flatness level using the relational expression and estimating the axial misalignment angle of the radar apparatus and the mounting height of the radar apparatus, in response to determining that the road surface is not flat, and
• adjusting, by an adjustment apparatus mounted to the radar apparatus, a mounting angle of the radar apparatus and the mounting height of the radar apparatus, based on the estimated axial misalignment angle of the radar apparatus and the estimated height of the radar apparatus.