Diagnostic Maintenance: A Technique Using a Computer

A possible technique and the attending software needs for advanced computer controlled checkout equipment, based on transfer properties, are presented in this paper. By employing the transfer function, single measurements can be used to designate the status of relatively complex entities and equipment descriptive matrices can be readily formed. In many cases, such an analysis allows for deeper piece-part fault localization than would be possible from test terminals alone. Matrix manipulations are used to perform tests, localize faults and predict performance. A hierarchical listing of matrices is used to give the computer a description of the unit under test. In addition, the problem of providing a practical method of solving problems under access points restrictions has also been taken into account. Based on these restrictions and on the proposed mathematical tools, a program flow chart is shown to outline these functions. Table-updating (learning) features are incorporated into the program. Essentially, the program consists of a man-written executive program and subroutines which are employed by a computer to derive the actual checkout program used by the checkout computer. This goal is accomplished by applying, under computer control, specific parameters to general routines. The stimuli selection is accomplished by the computer by cross-referencing given restrictions against circuit type and functional data. In formulating the checkout technique, both man-performed and machine-performed checkout processes were examined in order to combine the desirable features of each into an optimum technique.