Man-machine interfaces, trends and needs

Abstract

Today's sophisticated digital drives provide an abundance of control and diagnostic data for which a man-machine interface is required in order for the operator to interact with the machine. This paper describes the application of off-the-shelf graphical user interface development software and personal computers to provide the man-machine interface for a Paper Machine Winder and Paper Machine drive system. INIROUCCTIONIn the not so distant past, the primary means with which to interface with a drive system was via an operator's benchboard(s) crammed with a multitude of industrial-sized pushbuttons, switches, potentiometers and gauges. These devices were then hardwired to drive system panels, relay panels or PLC's (programmable logic controllers) containing an assortment of analog and digital inputloutput modules.With the introduction of the digital drive came the high speed data highways of today's control systems. These data highways provided a means with which to transmit digital data, using a single communications module. at a speed which a1 lowcd for distributed control.It seemed the next logical step would be to incorporate the operator control or MMI (man-machine interface) as part of the distributed control architecture by having it communicate over the same data highways. In order to accomplish this the MMK must be transformed into the digital world using personal computers (PC's) running graphical user interface (GUI) software.Once transformed, a far greater amount of information is available to the operator in a more functional and digestible mannei This empowers the operator to make decisions at a much higher lekel than in the past and consequently. ha5 more control over the process and oftcn develops a new sense orpride and res~onsibility concerning his roll in the production of a qualit\ product ' ' MMI DESIGN CON\,ENTIONS lJsirc A GUIWhen designing if GlJI it is first necessary to define a set of conventions regarding presentation of data and use of color. The intmtion is to aid the operator in interpreting, quickly and easily, the information displayed on the screen. Often, conventions of this kind alrcady exist for traditional benchboard controls and need only be adapted slightly to suit the GIJI. The following are examples of conventions developed for the Paper Machine Winder and Paper Machine MMI's:A . Referenca'Setpoint data vs. ActuaUFeedbuck dafu numeric data used to indicate a reference or setpoint value is displayed as black numerals on a grey background, i.e. Winder speed setpoint. numeric data used to indicate an actual or feedback value is displayed as yellow numerals on a black background, i.e. Winder speed feedback numeric data used to indicate the magnitude of a parameter being trended IS displayed as black numerals on a background color that matches the color of the line the parameter is being trended in. R Sturt/Stop vs OtdOf pushhutton controlWhen graphical representations of pushbuttons are used for stadstop type control of a functionwhen the function is offor stopped (Fig.2): the...