Abstract: Besides fixed display element information for merely displaying a fixed screen, variable display element information for variably displaying a variable display element whose display content changes, input element information representing the relationship of correspondence between the input means and an operation switch contained in a relevant component, and the operation program information for operating the relevant component as required, which are necessary for the relevant component to completely function as a component, are capable of being set and registered with respect to component data. In addition, the set and registered component is allowed to be handled in a component data unit when user screen data is generated. Accordingly, if the components are registered in a library, the possibility of use by a third party can be drastically increased, and the number of work steps during the screen generation by the user can be drastically decreased.

Abstract: A vehicle is guided along a desired path forwardly and backwardly by electromagnetically detecting deflection and attitude angle of the vehicle with respect to a guidance cable carrying an alternating current and producing a magnetic field.The deflection of the vehicle thus detected is compared with a predetermined deflection value from the guidance cable to produce an attitude angle setting signal, which is subsequently compared with the detected attitude angle to produce a steering control signal according to which the vehicle is controlled to run a desired path.