To stop a moving device by moving by a desired quantity in the desired direction with high accuracy by providing a driving means for driving them in the mutually crossing X, Y axis direction when a support plate and a base member float and driving itself in the X, Y axis direction when they do not float, on the under surface of the support plate.

An X, Y axis driving device 30 is arranged on the inside of a base member 10 and on the under side of a support plate. Here, the whole weight of the base member 10, the support plate and a gear measuring device being a loading object is set to almost 500 kg, and weight of only the X, Y axis driving device 30 is set to about 20 kg. Then, when actuating stepping motors 36, 44 without floating the base member 10, since the weight of the X, Y axis driving device 30 is fairly smaller than the total weight, the X, Y axis driving device 30 itself moves. Thus, after moving the X, Y axis driving device 30, the base member 10 is floated, and the X, Y axis driving device 30 is driven so that a moving device can be stopped by moving by a desired quantity in the desired direction with high accuracy.