<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> I've about finished reading "Numerical Control" by J. Francis Reintjes, which details the early days of CNC and the development of APT, and recommend it. For those of you that may have read "Forces of Production" by David Noble,  the Reintjes/MIT version of CNC history is quite different. It is much more credible to me as numerous references are supplied and the content is the history of technology development rather than (IMHO) politically biased sociology.  Noble's assertion that MIT "stole" Parson's invention is demolished.  However, in the second half of the Reintjes book, he drifts much into computer systems development history rather than staying focused on CAD/CAM/CNC developments. As one current web CNC tutorial notes, "APT methods did not adapt well to a graphics world and most people consider it obsolete, but APT remains a very powerful, and in some cases the best, tool for repetitive programming tasks."   What Ross/MIT set out to do was machine very complex, smooth and precise 3D surfaces, usually requiring 5 axis CNC tools.   Early work was  focused on BIG machine tools, e.g 6' x 12' x 6' and larger work tables and essentially entirely driven by military applications.  Today, this is a small part of the CNC machine tool industry.  Part design today is rapidly moving to 3D solids modeling CAD, followed by automatic CAM and post processing to generate G codes that directly drive the CNC machine controller.  Usually, there is some hand editing of G-codes.  An analogy to software writing might be "design/code at the flowchart level and then manually edit the automatically generated assembly code".  Mighty strange, but then so is the continued use of Fortran. Certainly, many of the second half 20th century "gee-whiz" weapons of  war couldn't have been built without APT.  How useful to the free world such technology will be in the 21st century seems to be an open question at this time. I found one company making a PC version of APT, see  <a class="moz-txt-link-freetext" href="http://www.pcapt.com/pcapt.htm">http://www.pcapt.com/pcapt.htm</a> Grant Al Kossow wrote: <blockquote cite="mid45CE7C80.6090809@bitsavers.org" type="cite"><a class="moz-txt-link-abbreviated" href="mailto:skyvis@skyvis.best.vwh.net">skyvis@skyvis.best.vwh.net</a> wrote: <blockquote type="cite"> <blockquote type="cite"> DOUG ROSS     DOUG ROSS     By Bryan Marquard, Globe Staff  |  February 10, 2007 While still in high school, Doug Ross performed a full assembly program of music he had composed. By his late 20s, he had developed a key computer language and coined the term computer-assisted design. A decade later, he taught MIT's first graduate course in software engineering. Perhaps not surprisingly, he occasionally thought daily tasks lacked sufficient challenge. Mr. Ross, who created APT, the automatically programmed tool computer language, died Jan. 31 at his home in the Brookhaven at Lexington care </blockquote>    For those who are interested I have a copy of APT for the 7090. It will compile under IBSYS under simulator. But I have no idea how to use it. Rich </blockquote> There is a scan of two MIT Tech reports that Mr. Ross wrote on APT here: <a class="moz-txt-link-freetext" href="http://bitsavers.org/pdf/mit/whirlwind/apt">http://bitsavers.org/pdf/mit/whirlwind/apt</a> _______________________________________________ SCC_active mailing list <a class="moz-txt-link-abbreviated" href="mailto:SCC_active@computerhistory.org">SCC_active@computerhistory.org</a> <a class="moz-txt-link-freetext" href="http://mail.computerhistory.org/mailman/listinfo/scc_active">http://mail.computerhistory.org/mailman/listinfo/scc_active</a> </blockquote> </body> </html>