Abstract: The interior of a first measurement surface and the interior of a second measurement surface traveling together with a measuring vehicle are scanned to acquire first measurement coordinate points and second measurement coordinate points, respectively. A first comparison point cloud representing a comparison part on a surface of a structure is extracted from the first measurement coordinate points. A second comparison point cloud representing a comparison part on the surface of the structure is extracted from the second measurement coordinate points. A difference between the first comparison point cloud and the second comparison point cloud corresponding to measurement of a common comparison part on the surface of the structure is calculated. Error having time dependence included in the first measurement coordinate points and the second measurement coordinate points is calculated on the basis of the calculated difference. The measurement coordinate points are corrected on the basis of the calculated error.

Abstract: A slope sample value at a sample point on a target route and a distance sample value from a reference point on the target route to the sample point are calculated based on three-dimensional position data of the target route. Undetermined elements contained in a model formula for the approximation formula representing relation between the slope sample value and the distance sample value are determined using an error evaluation formula for the model formula. The error evaluation formula contains a slope error evaluation component for evaluating a slope error between the slope sample value and a slope model value that is calculated using the model formula, and an altitude error evaluation component for evaluating an altitude error between an altitude model value that is obtained through integration of the slope model value and an altitude value that is obtained from the three-dimensional position data.

Abstract: A map generation device is configured to determine evaluation value of each of a plurality of evaluation items that serve as indices for evaluation the reliability of the positional information of the planimetric feature. The plurality of evaluation items include any of an error amount when arrangement of composing points of the planimetric feature is approximated, a parallelism between an arrangement direction of composing points of the planimetric feature and a movement trajectory of the measuring vehicle, a distance between a position indicated by the position information of the planimetric feature and a position of the measuring vehicle when the position of the planimetric feature is measured, an absolute value of reflection intensity of a position of the planimetric feature obtained from the measurement information or a difference between a position of the planimetric feature and surrounding reflection intensity of the planimetric feature, and so on.

Abstract: The interior of a first measurement surface and the interior of a second measurement surface traveling together with a measuring vehicle are scanned to acquire first measurement coordinate points and second measurement coordinate points, respectively. A first comparison point cloud representing a comparison part on a surface of a structure is extracted from the first measurement coordinate points. A second comparison point cloud representing a comparison part on the surface of the structure is extracted from the second measurement coordinate points. A difference between the first comparison point cloud and the second comparison point cloud corresponding to measurement of a common comparison part on the surface of the structure is calculated. Error having time dependence included in the first measurement coordinate points and the second measurement coordinate points is calculated on the basis of the calculated difference. The measurement coordinate points are corrected on the basis of the calculated error.

Abstract: A slope sample value at a sample point on a target route and a distance sample value from a reference point on the target route to the sample point are calculated based on three-dimensional position data of the target route. Undetermined elements contained in a model formula for the approximation formula representing relation between the slope sample value and the distance sample value are determined using an error evaluation formula for the model formula. The error evaluation formula contains a slope error evaluation component for evaluating a slope error between the slope sample value and a slope model value that is calculated using the model formula, and an altitude error evaluation component for evaluating an altitude error between an altitude model value that is obtained through integration of the slope model value and an altitude value that is obtained from the three-dimensional position data.