[step-manufacturing] Minutes of Renton Meeting

[Martin Hardwick]

My apologies. I sent this message to the wrong exploder and did not know 
that T24 did not get a copy.

Martin
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Attendees
Martin Hardwick, STEP Tools, USA
Rich Morihara, Boeing, USA
David Odendahl, Boeing, USA
Fred Proctor, NIST, USA
Sid Venkatesh, Boeing, USA
Fiona Zhao, NIST/New Zealand
Shinya Uesaka, Sumitomo Hardmetal Corp, Japan
David Blair, FARO Technologies, USA
Fred Richter, Boeing USA

ftp://www.steptools.com/private/Renton/2010_T24_group_photo.JPG

The ISO T24 STEP-Manufacturing team met at the Boeing Renton plant on 
October 12 and 13, 2010. The meeting featured a demonstration of closed 
loop machining using a FARO arm and the Okuma machine tool. The part 
machined was the Boxy part machined at previous meetings but in this 
demonstration the orientation of the part in X, Y and Z was deliberately 
offset using shims. In the demonstration the orientation of the part was 
determined by using the FARO arm to measure three faces. The geometry of 
the three faces was then delivered to the STEP-NC environment as a STEP 
file. In the STEP-NC file, two workingsteps were used to process these 
measurements. The first workingstep registered the coordinates of the 
fixture using the geometry defined by machining the first setup. The 
second workingstep computed the coordinates of each setup by measuring 
the coordinates of the part as setup against the coordinates as defined 
in CAD and determining the difference using the coordinates of the fixture.

ftp://www.steptools.com/private/Renton/Setup_7_completed_small.jpg

The demonstration was a success. We showed that the orientation of the 
part can change in three dimensions and three directions and that minor 
issues such as changes to the size of the fixture spacer will be 
non-issues in STEP-NC. The next priority is to extend the compensation 
to the measurement of hole sizes so that the system can compensate for 
changes to the diameter of a drill during machining and STEP-NC can be 
applied to the problem of drilling holes in hard flexible materials. 
Other issues that can be explored include restricting compensations to 
one or two dimensions when variations in the other dimensions cannot be 
allowed (for example when machining in three axes), and error control so 
that machining is stopped when the error in one of the fixed or unfixed 
dimensions exceeds predefined limits.

After the demonstration, the meeting discussed how to develop a second 
edition of the standard so that the CAD, CAM and CNC vendors can be 
required to support the interfaces necessary for machining compensation 
in five axes, and how to implement a next generation machining 
simulation service for STEP-NC. The latter is being funded by a DARPA 
SBIR program and the proposal is to build a simulation service that can 
be used to link manufacturing operations across the country and across 
the globe.