Your E-mail and Presentation "Machining features and Machinin g Process Features"

[Martin Hardwick]

Jesse,

AP-238 is used to exchange data between process planning (aka CAM systems)
and CNC systems. For a CNC system AP-238 is the new input replacing the
very old RS274D (G code) standard. 

Advantages of AP-238 as an input to the CNC include:
* 3D geometry
* Features (as defined in AP-224)
* Sequencing language for operations that allows nested, conditional and
  concurrent operations
* Geometric (AIC 519) and parametric tolerances
* Tool requirements (so the CNC can pick best available tool)

There has been a tremendous effort in SC1 over the last 5 years to get
International Consensus on the information requirements for AP-238.
They are defined in ISO 14649 which is now at FDIS.

In my view AP-213 has been sitting on the shelf for 5+ years because
very few systems want to write AP-213 data and no systems want to read
this data.

I am very scared that the new AP-213 will try to become relevant by
being an alternative method for exchanging data between CAM and CNC
systems. Someone is already calling the new AP-213 STEP-NC.
The Army has been told it is STEP-NC and so has Focus Hope.

This will hurt the International consensus painfully built
by SC1, and open Pandora's box because if one team is allowed to
define a redundant manufacturing AP for CAM to CNC exchange then
any group should be allowed to do so.

Martin Hardwick


At 08:06 AM 1/11/2002 -0500, Jesse L. Crusey wrote:
>Martin,
>
>I thought AP213 was the output of process planning and AP213 is setting on
>the shelf at FDIS.  What are the major functionalities that AP238 brings to
>manufacturing that AP213 doesn't?  We have to remember there is a lot of
>legacy data in shops that are still valid and considered to be in
>production mode when parts are ordered and will remain so for year to come. 
>
>Jesse Crusey
>
>At 10:28 AM 1/10/02 -0500, Martin Hardwick wrote:
>>
>>Dear All,
>>
>>My own opinion is that AP-224 is the input to process planning and
>>AP-238 is the output.
>>
>>If AP-238 is NOT the output of Process Planning then what is, and
>>what is the name and functionality of the system that reads in the
>>new output and writes out AP-238?
>>
>>Potentially there are lots of applications that want to use the output of
>>process planning but do these applications have information requirements
>>that are not satisfied by AP-238 or could not be satisfied by making a
>>minor enhancement to AP-238?
>>
>>In PDM STEP did itself a lot of harm by continually inventing new Application
>>Protocols for trivial reasons- first AP-203 then AP-232 then AP-214 then
>>PDM Schema then PDM Modules and now PLCS. As an expert it is very unclear
>>to me why this was necessary. I really hope we can avoid making the same
>>mistake in manufacturing. Manufacturing is divided into CAD, CAM
>>and CNC systems how many AP's do we need? My answer is 2.
>>
>>Martin Hardwick
>>
>>
>>
>>At 02:48 PM 1/10/2002 +0000, Alan Crawford wrote:
>>
>>>Dear Chiaki Sakamoto 
>>>
>>>Thank you for distributing your set of slides on the machining process
>feature.  The diagrams, in particular Fig. 1 will be a significant help in
>identifying the migration of design data in a form ready for machining
>processes. 
>>>
>>>For AP224 the features are design representations prepared in a way
>useful for manufacture but that the features are independent of the method
>or processes used to manufacture.  In AP238, the features in a part file
>need to represent a component in the complete form for that operation, on
>that workcentre.  An updated approach is required for process planning in
>STEP,  to establish the machining sequence.  Evidently one new task for
>process planning is to prepare the feature information in a form required
>for each workstation, it will also be important to exclude some features
>not required until later in the manufacturing sequence.
>>>
>>>As the scope of STEPNC is extended to consider that more than one machine
>for the manufacture of a component [the general case], the requirement for
>in-process features to describe part-machined features is evident.
>>>
>>>Best regards 
>>>
>>>Alan Crawford 
>>>
>>>LSC Group Ltd, Concept House, Victoria Road, Tamworth, Staffordshire, B79
>7HL, United Kingdom 
>>>
>>>email:  alc at lsc.co.uk 
>>>Tel:    + 44 (0) 182 770 8582 
>>>Fax:    + 44 (0) 709 236 3698 
>>>mobile:         + 44 (0) 797 456 4773 
>>>
>>>-----Original Message----- 
>>>From: chiaki sakamoto
>[<mailto:chiaki_sakamoto at keg.komatsu.co.jp>mailto:chiaki_sakamoto at keg.komats
>u.co.jp] 
>>>Sent: 07 January 2002 08:37 
>>>To: Friedrich Glantschnig 
>>>Cc: Alan Crawford; David Loffredo; Frederick Proctor; Len
>Slovensky(AP224); Suk-Hwan SUH; Jochen Wolf; Peter Mueller; Yong Tak Hyun;
>Martin Hardwick; Stefan Heusinger; kisinami at coin.eng.hokudai.ac.jp
>>>
>>>Subject: Re: Your E-mail and Presentation "Machining features and
>Machining Process Features" 
>>>
>>>
>>>
>>>
>>>Dear Mr.Glantschnig, 
>>>
>>> Thank you for your comments on my proposal. 
>>>
>
>>> My explanation was not enough. 
>>>So I added Fig.2 and its explanation in the attached file. 
>>>
>>> I think we have common understanding about Process Data Model. 
>>>
>>>Chiaki Sakamoto 
>>>Komatsu Engineering 
>>>
>>>(See attached file: Machining Process Feature.ppt) 
>>>
>>>
>>>
>>>
>>>
>>>"Friedrich Glantschnig" <fglantschnig at swissonline.ch> $BF|;~(J: 2002/01/03 
>>>20:07:39 
>>>
>>>"Friedrich Glantschnig"
><fglantschnig at swissonline.ch>$B$5$s$KJV?.$7$F$/$@$5$$(J 
>>>
>>>$B08 at h(J  :   $B:dK\(J $B at i=)(J 
>>>cc  : "Alan Crawford" <ALC at lsc.co.uk>, "David Loffredo" 
>>>      <loffredo at steptools.com>, "Frederick Proctor" 
>>>      <frederick.proctor at nist.gov>, "Len Slovensky\(AP224\)" 
>>>      <slovensky at scra.org>, "Suk-Hwan SUH" <shs at postech.ac.kr>, "Jochen 
>>>      Wolf" <j.wolf at wzl.rwth-aachen.de>, "Peter Mueller" 
>>>      <peter.mueller at erlf.siemens.de>, "Yong Tak Hyun" 
>>>      <hyt at wzl.rwth-aachen.de>, "Martin Hardwick" <hardwick at steptools.com>, 
>>>      "Stefan Heusinger" <stefan.heusinger at isw.uni-stuttgart.de> 
>>>$B7oL>(J  :   Your E-mail and Presentation "Machining features and
>Machining 
>>>      Process Features" 
>>>
>>> << File: ATT29790.txt >>  << File: Internet HTML >>  << File: Machining
>Process Feature.ppt >> 
>>>
>>>
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>>