GDA - Gensym Diagnostic Assistant
Gensym needed a product to simplify advanced monitoring and control systems based on generating events from statistical analysis of historical and current data, boolean and fuzzy logic, and to automate corrective actions.
Customers needed a tool that would shorten project implementation times and reduce implementation schedule risk. They also wanted a tool that could be used by domain experts, not just programmers. The initial beta customer, a Japanese government/nuclear industry consortium, wanted to directly enter logic diagrams rather than represent logic in text form, to make it easier to reliably translate existing fault tree diagrams into executable code.
Greg Stanley conceived of the idea of the Graphical Diagnostic Language (GDL), and developed it along with co-workers Eric Finch and Steve Fraleigh and others. We productized the result as the Gensym Diagnostic Assistant (GDA). GDL allowed domain experts to focus on the application logic (for filtering, calculations, statistics, recognizing events and recurring problems, diagnosing problems, managing displays, and taking corrective actions), rather than on programming in some text-based language. This was one of the first true graphical languages, along with LabView and GRAFCET that appeared around the same time. GDA was the first to combine both information flow diagrams and sequential control (workflow) diagrams into one language. Please see the GDA white papers)
GDA became Gensym’s most successful product after G2, selling about 1500 copies and generating 15% of company revenue. Due to its popularity, later on it was bundled with each G2 sale.
The picture below shows an example screen shot. The graphical blocks are the “source code” for the logic and actions. Text fields are only comments. This view happens to show an operator message display as well, although the operator interface did not require looking at the logic diagrams.