Method for measuring gap and flush of vehicle parts and measuring tunnel
AssigneeEines Systems, S.L.U.
InventorsJesús Belda Pla, Jorge Broto Ruiz, José Arribas Lozano, María José Esteve Cubel
Life of this patent
Estimating the term…
Abstract
A method that is able to measure the gap and flush of vehicle parts by means of a measuring tunnel. The method is able to determine the coordinates in 3D of the edges or ends of two adjacent parts of a vehicle. The measuring tunnel includes several video cameras, LED lights, a conveyor, a position encoder that measures the movement of the vehicle; a total station that measures fixed points of the measuring tunnel structure; a calibration chessboard and a calibration pattern; processing and storage means to store images taken by the video cameras, Computer-Aided-Design files of the vehicles and an edge recognition algorithm.
Claims10
A method for measuring the gap and flush of vehicle parts by means of a measuring tunnel, the method comprising the following steps:
- calibrating video cameras comprised in the measuring tunnel by calculating intrinsic parameters and extrinsic parameters of the video cameras;
- building a common reference system -SCE- for the measuring tunnel and linking the video cameras to the common reference system -SCE-;
- calculating 3D coordinates by stereo vision of at least four reference points of a vehicle based on the common reference system -SCE- obtaining the X,Y,Z coordinates of each reference point;
- calculating the X,Y,Z coordinates of each reference point based on a vehicle reference system -SCV- from a Computer-Aided-Design file -CAD- with the three-dimensional vehicle measures;
- shooting light beams synchronized with the video cameras from at least two lights that reflect light off parts of the vehicle and fail to reflect light in a gap between the vehicle parts, such that the lack of light reflection is confined between edges that do reflect light;
- taking at least two synchronized 2D images of the vehicle parts lacking a reflection by means of the video cameras, wherein an identifier -ID- of each synchronized 2D image is associated with the spatial position of the vehicle with respect to the measuring tunnel, and applying an edge recognition algorithm that calculates the X,Y coordinates of each edge as well as of the identifier -ID- based on the common reference system -SCE-;
- combining the synchronized 2D images into 3D images wherein the edges in the 3D images have X,Y,Z coordinates linked to the common reference system -SCE-;
- calculating the X,Y,Z coordinates of the edges of the 3D images linked to the vehicle reference system -SCV- using the equation:
- SCV=Inverse(MR)×SCE
- wherein SCV is a matrix that defines the X,Y,Z coordinates linked to the vehicle reference system -SCV-;
- MR is the relationship matrix and SCE is a matrix that defines the X,Y,Z coordinates linked to the common reference system -SCE-;
- calculating a flush and a gap of the vehicle parts as the gap distance between the edges on coordinates X,Y,Z linked to the vehicle reference system -SCV-.
Dependencies are inferred from the claim text.