[Discuss] open hardware documentation survey

Bryan Bishop kanzure at gmail.com
Wed Mar 27 02:40:46 UTC 2013


Maybe I see where our misunderstanding happened.

What I wrote to Matt was a direct response to his
"design-by-committee" suggestion. When I read your first message in
reply to me, I was still thinking "holy crap how am I going to help
these guys avoid a design-by-committee disaster".. in that context,
your message (including "We need you to instruct us in this") gets
interpreted to mean that you would only consider-for-consideration the
topics I mentioned if I prepare a presentation to inform you about
their nature, existence, function or meaning. As you can imagine, that
was very startling for me to read because of how important they are to
creating any sort of informed decision about agreeing to a common file
format for packages, which informs a lot of other downstream decisions
about which tools to make and which tools to give GUIs to, or which
things might not conceptually work out from the various decisions on
file formats to keep our 'things' etc.

But now I think maybe you were not asking in that context of that
email you were replying to, and just asking out of general
curiosity... in which case I am sorry about the misunderstanding.
However, my original offer for talking whenever to elaborate on the
whatever open source hardware projects still applies.

Anyway, here is some basic ISO information as you requested. I brought
it up in the earlier emails because if Matt wants something designed
by committee, this is a big committee (tc184-sc4) with lots of
hardware companies backing it.


ISO 10303 is an ISO standard for the computer-interpretable
representation and exchange of product manufacturing information. Its
official title is: Automation systems and integration — Product data
representation and exchange. It is known informally as "STEP", which
stands for "Standard for the Exchange of Product model data". ISO
10303 can represent 3D objects in Computer-aided design (CAD) and
related information.

The international standard's objective is to provide a mechanism that
is capable of describing product data throughout the life cycle of a
product, independent from any particular system. The nature of this
description makes it suitable not only for neutral file exchange, but
also as a basis for implementing and sharing product databases and

Typically STEP can be used to exchange data between CAD,
computer-aided manufacturing, computer-aided engineering, product data
management/enterprise data modeling and other CAx systems. STEP is
addressing product data from mechanical and electrical design,
geometric dimensioning and tolerancing, analysis and manufacturing,
with additional information specific to various industries such as
automotive, aerospace, building construction, ship, oil and gas,
process plants and others.

STEP is developed and maintained by the ISO technical committee TC
184, Automation systems and integration, sub-committee SC 4,
Industrial data. Like other ISO and IEC standards STEP is copyright by
ISO and is not freely available. However, the 10303 EXPRESS schemas
are freely available, as are the recommended practices for

Other standards developed and maintained by ISO TC 184/SC 4 are:
ISO 13584 PLIB - Parts Library
ISO 15531 MANDATE - Industrial manufacturing management data
ISO 15926 Process Plants including Oil and Gas facilities Life-Cycle data
ISO 18629 PSL- Process specification language
ISO 18876 IIDEAS - Integration of industrial data for exchange,
access, and sharing
ISO 22745 Open technical dictionaries and their application to master data
ISO 8000 Data quality
STEP is closely related with PLIB (ISO 13584, IEC 61360).

The evolution of STEP can be divided into four release phases. The
development of STEP started in 1984 as a successor of IGES, SET and
VDA-FS.[1] The initial plan was that "STEP shall be based on one
single, complete, implementation-independent Product Information
Model, which shall be the Master Record of the integrated topical and
application information models".[2] But because of the complexity, the
standard had to be broken up into smaller parts that can be developed,
balloted and approved separately.[3] In 1994/95 ISO published the
initial release of STEP as international standards (IS) with the parts
1, 11, 21, 31, 41, 42, 43, 44, 46, 101, AP 201 and AP 203.[4] Today AP
203 Configuration controlled 3D design is still one of the most
important parts of STEP and supported by many CAD systems for import
and export.

In the second phase the capabilities of STEP got widely extended,
primarily for the design of products in the aerospace, automotive,
electrical, electronic, and other industries. This phase ended in the
year 2002 with the second major release, including the STEP parts AP
202, 209, AP 210, AP 212, AP 214, AP 224, AP 225, AP 227, AP 232.[5]
Basic harmonization between the APs especially in the geometric areas
was achieved by introducing the Application Interpreted Constructs
(AIC, 500 series).

A major problem with the monolithic APs of the first and second
release is that they are too big, have too much overlap with each
other and are not sufficiently harmonized. These deficits lead to the
development of the STEP modular architecture (400 and 1000 series).[6]
This activity was primarily driven by new AP covering additional
life-cycle phases such as early requirement analysis (AP 233) and
maintenance and repair (AP 239), and also new industrial areas (AP
221, 236). New editions of the previous monolithic APs on a modular
basis have been developed (AP 203, 209, 210). The publication of these
new editions coincide with the release of the new ISO product SMRL,
the STEP Module and Resource Library, in 2010 that contains all STEP
resource parts and application modules on a single CD. The SMRL will
be revised frequently and is available at a much lower cost than
buying all the parts separately. At the end of 2010 the seventh Change
Request (CR) of the SMRL has been worked out.

In mid 2010 the development of the new major AP 242 Managed model
based 3d engineering was initiated. The first edition of AP242 is
expected to be technically complete in 2011 and is dedicated to
replace the most successful STEP APs 203, 214 and other APs in the
mechanical design area in an upward compatible way. In particular it
will contain major updates in the area of Geometric dimensioning and
tolerancing, Kinematics, and Tessellation. Future editions of AP242
will extend the scope further into areas such as electrical harnesses.


Design APs:
AP 201, Explicit draughting. Simple 2D drawing geometry related to a
product. No association, no assembly hierarchy.
AP 202, Associative draughting. 2D/3D drawing with association, but no
product structure.
AP 203, Configuration controlled 3D designs of mechanical parts and assemblies.
AP 204, Mechanical design using boundary representation
AP 207, Sheet metal die planning and design
AP 209, Composite and metallic structural analysis and related design
AP 214, Core data for automotive mechanical design processes
AP 235, Materials information for the design and verification of products
AP 236, Furniture product data and project data
AP 242, Managed model based 3d engineering (under development)
Connectivity oriented electric, electronic and piping/ventilation:
AP 210, Electronic assembly, interconnect and packaging design. The
most complex and sophisticated STEP AP.
AP 212, Electrotechnical design and installation.
AP 227, Plant spatial configuration
AP 215, Ship arrangement
AP 216, Ship moulded forms
AP 218, Ship structures
AP 225, Building elements using explicit shape representation
AP 232, Technical data packaging core information and exchange
AP 233, Systems engineering data representation
AP 237, Fluid dynamics has been cancelled and the functionality
included in AP 209
Manufacturing APs:
AP 219, Dimensional inspection information exchange
AP 223, Exchange of design and manufacturing product information for cast parts
AP 224, Mechanical product definition for process plans using machining features
AP 238 - Application interpreted model for computer numeric controllers
AP 240, Process plans for machined products
Life cycle support APs:
AP 239, Product life cycle support
AP 221, Functional data and schematic representation of process plants
AP 241, Generic Model for Life Cycle Support of AEC Facilities (planned)

Actually, ISO 10303 is nothing I would wish upon anyone because of how
convoluted (and expensive) it is; but it's an excellent example of a
standard in wide adoption that solves a lot of the core problems in
CAD. The other end of the spectrum are smaller tools like thingdoc
that solve precisely one problem well (generating documentation from
source code comments, much like doxygen or mocco or docco, or sphinx
or whatever the flavor-of-the-week documentation generator is), just
based on plaintext in a git repo (folder) that others are free to
automatically download through whatever other open source hardware
tools they so choose.

- Bryan
1 512 203 0507

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