以圖像為基礎的程序控制系統快速雛型發展環境

Abstract

目前建立程序控制軟體雛形的方法均缺乏描述控制環境設備之能力，因此 在程序規格軟體雛形執行時，無法模擬周邊設備之運轉情況而得不到控制 變數變化的訊息，此外在雛形執行時只能顯示規格執行的過程，無法讓程 序工程師清楚地看到整個系統中各程序的運轉情況，使其不易確認程序控 制軟體規格功能的正確性。本研究主要提出一套程序控制軟體快速雛形環 境，提供系統分析師： (1) 以正規語言描述程序控制軟體規格之功能。 (2) 以正規語言描述各控制環境設備之運轉狀況。 (3) 以圖像及符號代 表控制設備，使規格軟體執行時，可由圖像變化看出整個程序控制系統之 運轉狀況。本環境主要特色如下： (1) 提供環境模式之描述，可定義系 統裝置及生產人員之正常及不正常的運作。 (2) 雛形執行時，直接以圖 像顯示各生產程序之運作，使程序工程師更易驗證規格程式之正確性。 (3) 以物件表示環境模式之程序控制變數及裝置控制訊號，適於作再利用 。此程序控制軟體快速雛形環境已在IBM個人電腦之視窗環境上使用 Visual Basic語言製作完成。 Current methods to construct the prototype of a process control software are lack of the capability to specify the operation of controlled devices. When the prototype is executed, it cannot show the change of the controlled process, and the execution of the prototype can only display the execution of the control software. Therefore, the process engineers cannot certify the correctness of the specification of process control software because they can not clearly know the operations of the control processes in the system. To solve the above problem, this thesis proposes a new rapid prototyping environment for process control systems, so the system analyst can: (1) use formal specification language PML to define the specification of process control software. (2) use formal language to define the operations of the controlled devices. (3) use the icons and the symbols to denote the control devices. Since all control processes are represented by icon, when the specification of a control software is executed, the process engineer can easily understand the behavior of the control process. The major contribution of this new system are: (1) it provides a formal description of environment model to specify the normal or abnormal operations of the devices and the on-line workers. (2) it use icons to display the operations of control processes so that the process engineers can verify the correctness of specification easily. (3) it use object/class to represent the control process. This rapid prototyping environment for process control systems has been implemented on the IBM PC Window environment using by Visual Basic language.