COMMENT ⊗   VALID 00002 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002		The preparation  of drawings to  control the  construction of
C00009 ENDMK
C⊗;
	The preparation  of drawings to  control the  construction of
buildings  and  the production  of  smaller objects  is  an important
source of delay and expense.   Besides drawings themselves, bills  of
material, instructions  for numerically controlled machine  tools and
automatic  wiring  machines  are becoming  of  increasing importance.
All these  normally  involve a  different group  of  people from  the
engineers  and architects  who design  the products.  Modification of
drawings once produced  is also very  expensive especially since  the
modifications have  to be  made by  different people than  originally
made  them.  Anything that  can reduce the cost  and delay of drawing
will increase the  promptness with which society  can respond to  its
technological problems.   The  current energy crisis  illustrates the
fact  that we often don't recognize problems  until they are so acute
that fast action is required.

	Many computer aids  to design have  been developed since  the
late 1950s and  have met with a mixed reception.   Some have met with
complete acceptance  and are  the  standard way  of doing  things  in
particular  industries.     For   example,  computer   aids  to   the
preparation  of integrated  circuit  masks are  in wide  use.   Other
proposals have not proved  cost-effective, because the equipment  was
too expensive  or because  the system  was too  inflexible.   Our own
experience  with computer aids to the  production of drawings has ben
good.   The system  developed here  by Richard  Helliwell for  making
logic  diagrams,  printed  circuit  board layouts,  instructions  for
automatic  wiring  machines  and   board  drilling  machines  is   in
continuous use here and parts  of it have been adopted by  MIT and by
Digital Equipment Corporation.   Part of the success of the system is
based on  the fact  that  it operates  in the  context of  a  general
time-sharing system with all of  its facilities and doesn't represent
an independent investment in hardware.

	Our  proposed research will advance the  art in the following
respects:

	1. The direct  description of three-dimensional objects  will
be  more  easier and  more  flexible than  the  present technique  of
making two  dimensional drawings.    Such descriptions  will  require
less change  when design is  changed and  can produce whatever  views
are required when requirements change.

	2.   The   three-dimensional   descriptions   will  be   more
convenient for generating information  for controlling machine  tools
and automatic assembly systems.

	3. The resulting  system will run on  a standard time-sharing
system  for the  PDP-10 (certainly on  TENEX and  probably on TOPS-10
also).  An inducstrial user of the system will  require only suitable
display  terminals  which  can   be  connected  to  the  computer  by
telephone.  This  will reduce by  an order of  magnitude the  capital
cost of computer aided design, since most  of the present systems run
on dedicated computers.

	We are not  yet in communication with potential users of this
system, but we anticipate  interest comparable to that already  shown
in our logic and circuit design system.

	This  work is  related to  other activities  of the  Stanford
Artificial   Intelligence  Laboratory,  especially  to  the  work  in
automated assembly  which needs  to  start from  descriptions of  the
objects  being  assembled. The  ability  of  the  proposed system  to
handle motions of  the objects  as well as  static descriptions  will
aid in the development of the "automation  assembly language".  It is
also  related to  a proposed  project aimed  at an  automated machine
shop.

	The  Stanford  Artificial   Intelligence  Laboratory  has   a
management  structure suited  to  this  kind of  project.   Both  the
Director,  John McCarthy, and the  Executive Officer, Lester Earnest,
have experience in managing  such projects and a special  interest in
this one.

	Successful  completion of  the research  will  make available
programs that will make design faster and cheaper.