A welding electrode is mounted in a tool holder that is part of a handle apparatus. When the element is a straight line element, whether or not the distance D between the start point and the end point of the element in a direction orthogonal to the axis of rotation of the workpiece is equal to or greater than a preset value Ds is determined. The hydrogen gas fuels a hydrogen engine, and the steam produced in the engine is used to drive an electricity generator and subsequently a turbine, whereby the electricity is stored in a leadacid cell used together with the fuel cell. As will be seen, the degree of interrelatedness of these components can vary, but the result is a uniformity of high quality product which enables a wider range of food stuffing. This arrangement enables the top transport foot to be displaced upwards into the rest position, so that accessories can be fixed to the presser bar. The combined STAP-MUD methods and systems increase the probability of successful user detection by taking advantage of the benefits of each reception method.