PURPOSE: To improve the reliability of measurement and to automate and rationalize operation by stopping an automobile being conveyed on a rack table TB which moves cyclically, and matching the part of the automobile to be measured with a wheel alignment measuring instrument position.

CONSTITUTION: The TB 47 is supported in the center on an intermediate frame FM 38 horizontally rotatably, and plural air bearings 46 seated on the FM 38 normally are mounted below the TB. While a centering spring which controls the front-rear and right-left positions of the TB 47 about the FM 38 at the time of the air floating of the bearing 46 is extended between the TB 47 and FM 38, the FM 38 is provided movably to an under FM 35 below it. Then a lock plate 41 which is projected in the center below the FM 38 normally is restrained at the center position on the FM 35 to center the FM 38 to the FM 35. Consequently, the vehicle 5 which is conveyed by a conveyor for conveyance is passed to the TB 47 moving synchronously right below it, and then rotated together with the TB 47 and moved forth and back, and right and left, so that the front-rear and right-left directions of the vehicle 5 are matched with the base part below the TB 47.