Olasov@MIT-MULTICS.ARPA.UUCP (03/14/87)
I'm doing research on applications of various expert system
techniques in architectural design <and, secondarily,
engineering design>, with emphasis on interfacing knowledge
based systems with CAD systems.
In my research, I've developed a number of shells external
to the CAD system, that are written in LISP, and that use
different entry points to the CAD system. I've used rule
based pattern matching shells and binary discrimination networks.
I've also tried writing shells for an IBM-PC CAD package
called AutoCAD, which has an internal LISP interpreter, with
interesting results. I expected that an interpreter resident
within the CAD system should be a superior strategy to that
of having an interface of an external shell to the CAD
package. I found that in the case of AutoLISP however, the
internal LISP interpreter in AutoCAD, memory requirements for
even trivial pattern matching algorhythms usually proved to
be too great (yes, even in the latest versions of AutoCAD).
Also, AutoLISP functions represent a very small subset of a
full Common LISP, which makes ES applications exceedingly
difficult to write, as functions which would otherwise be
primitively defined must be defined at the interpreter level,
thus using much of the precious memory it has to allocate to
function definitions. Generally, small applications were
successful.
I would be very interested to learn about the research and
experiences of others who are using, or attempting to use,
expert system applications in CAD, particularly for
architectural design purposes.
Cheers,
Ben Olasov <Olasov@MIT-MULTICS.ARPA>