[step-manufacturing] Minutes of telecon on March7

[Martin Hardwick]

Attendees
--------------
Martin Hardwick, STEP Tools, USA
David Loffredo, STEP Tools, USA
Mikael Hedlind, KTH, Sweden
Yujiang Li, KTH Sweden
Bengt Olsson, Sandvik, Sweden
Ian Stroud, EPFL, Switzerland
Leon Xu, Boeing, USA
Fred Proctor, NIST, USA
Bob Erickson, Pratt & Whitney, USA
Sid Venkatesh, Boeing USA
Jean Brange, Bosot-Conseil, France
Alain Brail, Airbus (retired), France
David Madeley, Siemens, UK

Apologies for Absence
-------------------------------
David Odendahl, Boeing, USA

1. Programming Issues and  Interest in Modelica for modeling the 
function in "form, fit and function".

There is interest in combining Modelica with CAD models including STEP 
models. Dassault Systemes has a project that is investigating the matter 
and a talk on the OPENPROD initiative of the University of Lingkoping 
University in Sweden will be making a presentation at the SC4 Industry 
day on June 13 in Sweden.

http://www.ida.liu.se/~pelab/OpenProd/

The WebGL STEP and STEP-NC models on the STEP Tools web pages have been 
updated to include color and will soon included text as well.

http://www.steptools.com/demos/

These demos are highly threaded code written in JavaScript and driven by 
XML information derived from the STEP data for AP-242 and AP-238. The 
threads respond to different events of which there can be many in a 
typical JavaScript/HTML5 application.

For STEP applications we would like to be able to generate events when 
significant things happen (such as the tool moves or a workingstep 
starts) and we would like to be able to access relevant information in 
the functions that service the events. The traditional SDAI model does 
not meet either of these requirements because there is no concept of a 
trigger and because having to navigate to the data you need from the 
SDAI root in each service function would be tedious to code and slow to 
execute.

Therefore, we are working on a concept of a Simulation SDAI. The 
Simulation SDAI will be for highly threaded, event driven applications 
like iPhone's, iPad's and machine tool controls. There will be at least 
two constructs: Triggers and Wrappers.

A Trigger will signal an event when a monitored quantity changes. 
Examples might include:
1. The tool tip moves.
2. A user selected workingstep starts executing.
3. The doors of the machine are closed.

A Wrapper will wrap STEP information that the user (JavaScript or 
similar programmer) wants to access in the function that services an 
event. Examples might include:
1. The new position of the tool tip in machine space coordinates and 
part space coordinates.
2. The definition of a plane on the workpiece that must be measured to 
set a  compensation value before the workingstep executes.
3. The state of the project which must be set from machinable to 
unmachinable or vice versa when the doors open and close.

The wrappers will give an API interface into the relevant data which 
will have been selected from the STEP-NC model via some click and pick 
interface. The data will be wrapped so that a system can decide to store 
it locally, on a cloud server or somewhere else and so that the 
representation of the data can be optimized for different kinds of 
applications.

The wrapper API will be derived from the Normative STEP information. In 
many cases it will be ARM level information but there is also 
significant AIM level data in the geometery and tolerances that the end 
users will want wrapped as well. The mechanism for defining the data 
that needs to be wrapped has not yet been decided. One of the issues 
with STEP is the overwhelming volumes of information that must be 
understood to process its data so it would be nice if the new SDAI can 
be configured to include just the information that the programmer needs 
to know.

2. CAM to CAM Data Exchange

We talked briefly about an upcoming project that will be funded to help 
the CAM vendors read STEP-NC data. The goal is to make it possible for 
the supply chain of an OEM to read STEP-NC data into their preferred CAM 
systems. This will allow the OEM to send a working process to its 
suppliers who will then be able to choose to run that process as-is or 
make optimizations. The project will be run in four six month cycles 
with the first cycle (Cycle 0) constructing a set of reference test 
parts and the subsequent cycles guiding the CAD vendors through the 
information resources necessary to read and process hole drilling (Cycle 
1), pocket milling (Cycle 2) and contour cutting (Cycle 3) operations. 
The project has an aggressive schedule and if funded it will want to 
have CAM vendors committing to participate by July 2nd.

During the discussion we realized that many of the OEM's would very much 
like such a project to take place and that they would be willing to 
write letters of support to get participation by the CAM vendors. 
Therefore, we decided that we should work to identify the names of the 
key decision makers so that we can prepare the letters.

3. June Demonstration

ftp://ftp.steptools.com/private/Stockholm2/STEP_manufacturing_demo_scenario_14_June_2012.pdf

A gear part is being considered for the June demonstration. The social 
event at the STEP meeting will feature a chance to drive large Scania 
trucks proving once again that techies never learn from "real world" 
experience only from synthetic gaming and programming ones. (One of our 
older members did think to ask for a joy stick). Casual observers are 
advised to avoid Sweden on June 12.

We discussed how to determine a kinematics algorithm in more detail. KTH 
has produced the algorithm shown below and STEP Tools will try to verify 
that it by using the described procedure to determine how to animate the 
axes of its current suite of machine tools.

ftp://ftp.steptools.com/private/Stockholm2/Conditions_for_different_kinematic_configurations.docx

The next telecon will be held on Wednesday March 28th - one week later 
than normal. A recording of this meeting is at the following ftp site

ftp://ftp.steptools.com/private/Stockholm2/stepmanuf_telecon_20120307.wmv

Martin Hardwick
Team Leader STEP-Manufacturing