Body-in-white measuring and positioning device, measuring system and measuring method

The invention relates to a body-in-white measuring and positioning device, a measuring system and a measuring method. The body-in-white measuring and positioning device comprises a main fixing table provided with a plurality of first leapfrog points, a positioning assembly comprising a positioning piece and a driving piece and a control system, and the positioning piece is arranged on the main fixing table and can stretch out and draw back in the first direction. The positioning part comprises a fixed column and a plurality of movable columns capable of moving relative to the fixed column in the second direction and/or the third direction, the fixed column and the movable columns are used for positioning the datum holes of the body in white, and the driving part is used for driving the fixed column and the movable columns to move. The control system is configured to be capable of generating coordinate data of the first leapfrog point according to the three-dimensional coordinates of the datum hole, and the co