Dating from the early 1980s, Knowledge-Based Engineering technology (KBE) has been used to capture and automate design and engineering, in particular in the automobile and aircraft industries.
A viable KBE system in the 21st century must provide users with a dynamic modeling feedback loop in an environment favorable to both exploration and experimentation, supplying various approaches for engineering a given set of artifacts. The fundamental properties of a KBE system must include automatic caching and dependency tracking for the scalable runtime performance of large models, minimal source code volume, and efficient and rapid tools for model development and debugging. And, not least, it must complement existing CAD systems.
A crucial aspect of a bonafide KBE system is its language-based core, embedded in a standardized, full-featured programming language, i.e., as a superset. The GDL (General-purpose Declarative Language) platform from Genworks achieves this by providing a domain-specific language (DSL) for KBE purposes, embedded in ANSI Common Lisp (often characterized as the “programmable programming language”). ANSI CL facilitates sophisticated code generation, written in a highly compact manner, which is then automatically expanded into the low-level CL, and finally machine code for execution.
This paper will consider the theoretical and practical issues associated with using such a language-centric approach for design and engineering automation. It also will address a number of the commonly heard objections from engineers and others to the use of a Lisp-based language, and respond to these largely unfounded objections.
The specific GDL platform by Genworks represents a contemporary and cost-effective KBE toolkit, affording all the significant benefits from the legacy, and very expensive, KBE systems, while incorporating a host of modern features, including: (1) portable web-based development and runtime environments, (2) compatibility of function with contemporary CAD and other data exchange formats, while (3) remaining free-standing from the proprietary CAD systems, with (4) robust underlying commercial components built into the package, to wit: (a) Allegro CL or Lispworks, and (b) SMLib surface/solid modeling. The paper will cover the specific features and benefits of Genworks GDL, as well as contrasting GDL to a number of alternative systems currently on the market.
Finally, this paper will explore a number of actual GDL applications, including a conceptual aircraft assembly, an aircraft wiring harness configurator, and an educational tool for modeling aerodynamic dragster models which provides a good example of KBE deployed using “web 2.0” AJAX techniques. The paper will also cover an AJAX-enabled browser-based graphical development environment for Genworks GDL called ta2.