Patent attributes
A test device includes a base plate configured to move on a slipping floor in X-Y directions by an air bearing, and rotate around a Z axis, a platform connected on the base plate by a movement connecting mechanism, and a magnetizing device disposed on a lower surface of the base plate to face the slipping floor and configured to change a magnetizing force to the slipping floor. The X-Y directions are substantially parallel to the slipping floor, and the Z axis is substantially perpendicular to the slipping floor. The base plate is disposed between the slipping floor and the platform. A magnetizing force of the magnetizing device to the slipping floor when the air bearing operates is stronger than magnetizing force of the magnetizing device to the slipping floor when the air bearing does not operate.