A restraint apparatus for protecting a vehicle occupant in a side impact or rollover event. A vibratory section composed of a part of the base film and a part of the piezoelectric stacked structure. The display controller performs display control to visualize, together with the diagram generated by the generating unit, at least one of information showing the status of the arm when the arm is at an angle illustrated in the diagram and information showing the status of a subject to be imaged when the arm is at the angle illustrated in the diagram. Each sub-aperture has its own receiver. A driven roller in continuous contact with one of the web ribbons draws it toward a cross cutter.