[step-manufacturing] Minutes of May 30 Conference Call

[Martin Hardwick]

Attendees
--------------
Martin Hardwick, STEP Tools, USA
David Loffredo, STEP Tools, USA
Mikael Hedlind, KTH, Sweden
Magnus Lundgren, KTH, Sweden
Bengt Olsson, Sandvik, Sweden
Leon Xu, Boeing, USA
Ronnie Fesperman, NIST, USA
Fred Proctor, NIST, USA
Vincent Marchini, Ameritech, USA
Alain Brail, Airbus (retired), France
Doron Cohen, ISCAR, Israel
Bob Erickson, Pratt & Whitney, USA

We reviewed the documentation for the cutting tool assembly model made 
by KTH and edited by Sandvik. The documentation shows how the various 
attributes defined by ISO 13399 are used to describe on of the cutting 
tool assemblies that will be used in the demonstration. As far as 
possible each quantity is only described once. There are some new 
notations being used to describe the connections codes the string $$$$ 
at the end of the code means that a value has not been specified. The 
string **** means any value is allowed.

ftp://ftp.steptools.com/private/Stockholm2/May30/Cutting%20tool%20modeling%20practice%20v0_2.docx

We had a discussion on the difference between mass and weight. Mass is 
an intrinsic value but weight depends on the local gravity value. It can 
vary slightly even on the same planet. Kilograms are a measure of mass 
and pounds are a measure of weight. The imperial unit for mass is slugs. 
For the cutting tool models we should document the mass in kilograms or 
subunits thereof.

The new documentation is very good and there was an immediate request to 
see similar types of documentation for other types of tools and tool 
assemblies where the functional tool length can be reset We used such 
assemblies for the CCAT demonstration but did not document to the new 
level of detail.

We discussed the machining process and the machining accuracy 
demonstration. NIST has begun testing the accuracy data and KTH will 
begin the first machining testing this weekend. The new model for the 
Mazak has a more elaborate tool changer and  STEP Tools is adding the 
new types of kinematics necessary to support this changer to the STEP-NC 
Explorer.

We discussed the external PMI modeling. The CAX-IF forum has determined 
that an NAUO identifier may not be sufficient to determine a unique 
instance of a product when there are multiple versions of a product in a 
file. Unfortunately, while it seems possible in principle, nobody in 
STEP manufacturing has access to such a data set so it is difficult to 
determine how the different versions might make the usage of a 
particular instance ambiguous.

We decided to continue with our plan and make the distributed PMI 
assembly data for the cutting tools using the data model published last 
week.

ftp://ftp.steptools.com/private/Stockholm2/External_geometric_representation_items.txt

A recording of this conference call is available at the following ftp. 
The next conference call will be at the regular time of 10:30AM Eastern 
on Wednesday June 6th.

ftp://ftp.steptools.com/private/Stockholm2/stepmanuf_telecon_20120530.wmv

Action Items
1. Ronnie to complete testing of the KTH  ASME B59.2 data
2. Martin to check with Doron on delivery date cutting tool item
3. STEP Tools to process kinematics for tool changer and fixture
4. KTH to add fixtures to STEP-NC data
5. KTH to complete tool assembly data
6. KTH to add additional properties to machine tool for acceleration 
etc. to the machine tool model
7. KTH to document machine tool properties
8. Magnus to make force measurements for Leon's tool force/deflection 
and direction prediction
9. Bengt to make further clarifications to cutting tool documentation 
example