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Modelling transition bends [message #1232] Mon, 01 September 2014 11:46 Go to next message
Christian Rahmig is currently offline  Christian Rahmig
Messages: 151
Registered: January 2011
Senior Member
Dear railML users,

with the ticket #251 (cf. [1]) we re-opened the topic of modelling
transition bends, which was already "discussed" here in the forum some
years ago (cp. [2]).

Within railML 3 we want to define a solid solution for this problem
since transition bends cannot be modelled with the existing
infrastructure schema 2.2.

Therefore: If you have any comments on the usage of transitions bends in
your applications and data models, feel free to post them here in order
not to forget about them and add them to the ticket.

[1] http://trac.railml.org/ticket/251
[2] http://www.railml.org/forum/ro/index.php?group=1&id=37

Best regards

--
Christian Rahmig
railML.infrastructure coordinator
Re: Modelling transition bends [message #1234 is a reply to message #1232] Mon, 01 December 2014 22:11 Go to previous messageGo to next message
Christian Rahmig is currently offline  Christian Rahmig
Messages: 151
Registered: January 2011
Senior Member
Dear everyone,

Am 01.09.2014 11:46, schrieb Christian Rahmig:
> Dear railML users,
>
> with the ticket #251 (cf. [1]) we re-opened the topic of modelling
> transition bends, which was already "discussed" here in the forum some
> years ago (cp. [2]).
>
> [...]

at the last railML.org conference in Paris on 07.10.2014, I presented a
solution for the transition curve problem, which is applicable to railML
2.2 (see [1]).

In particular, there are two possible approaches based on <radiusChange>
element (see [2]):

(1) add further description of the radiusChange using the description
attribute. Thus, the type of the curve can be described. If not empty,
possible values can be:

* UA_cubicParabola
* UA_parabola4
* UA_clothoide
* UA_WienerBogen
* UA_BlossBogen
* UA_Sinusoide
* UA_Cosinusoide
* UA_other
* UE, which marks the end of the transition curve.

(2) model the length of a transition curve between two other elements
using a new optional parameter named transitionLength:

* transitionLength = 0 is a direct connection between straight lines
and circular arcs
* transitionLength > 0 is a connection with a transition bend of a
certain length

Alternatively to (1), it could be also possible to put the name of the
transition curve element in a new optional parameter
geometryElementName, which would specify the linear track geometry
element starting at the marked point (radiusChange).

Any comments appreciated...

[1]
http://documents.railml.org/events/slides/2014-10-08_rahmig- railmltransitionbends.pdf
[2] https://trac.railml.org/ticket/251

--
Christian Rahmig
railML.infrastructure coordinator
Re: Modelling transition bends [message #1235 is a reply to message #1234] Wed, 03 December 2014 08:59 Go to previous messageGo to next message
Christian Rahmig is currently offline  Christian Rahmig
Messages: 151
Registered: January 2011
Senior Member
Dear everyone,

Am 01.12.2014 22:11, schrieb Christian Rahmig:
> [...]
>
> at the last railML.org conference in Paris on 07.10.2014, I presented a
> solution for the transition curve problem, which is applicable to railML
> 2.2 (see [1]).
>
> In particular, there are two possible approaches based on <radiusChange>
> element (see [2]):
>
> (1) add further description of the radiusChange using the description
> attribute. Thus, the type of the curve can be described. If not empty,
> possible values can be:
>
> * UA_cubicParabola
> * UA_parabola4
> * UA_clothoide
> * UA_WienerBogen
> * UA_BlossBogen
> * UA_Sinusoide
> * UA_Cosinusoide
> * UA_other
> * UE, which marks the end of the transition curve.
>
> [...]

> [1]
> http://documents.railml.org/events/slides/2014-10-08_rahmig- railmltransitionbends.pdf
>
> [2] https://trac.railml.org/ticket/251

Instead of the abbreviations 'UA' and 'UE' that are derived from the
German terms "Übergangsbogenanfang" and "Übergangasbogenende", it is
suggested to use the English driven abbreviations 'TS' (Tangent -
Spiral) and 'SC' (Spiral - Curve).

See ​
http://docs.autodesk.com/CIVIL/2010/ENU/AutoCAD%20Civil%2020 10%20User%20Documentation/index.html?url=WSfacf1429558a55de6 812d1041fa83470-7288.htm,topicNumber=d0e117613

Best regards

--
Christian Rahmig
railML.infrastructure coordinator
Re: Modelling transition bends [message #1236 is a reply to message #1235] Mon, 08 December 2014 11:00 Go to previous message
Christian Rahmig is currently offline  Christian Rahmig
Messages: 151
Registered: January 2011
Senior Member
Dear railML IS users,

Am 03.12.2014 08:59, schrieb Christian Rahmig:
> [...]
>>
>> (1) add further description of the radiusChange using the description
>> attribute. Thus, the type of the curve can be described. If not empty,
>> possible values can be:
>>
>> * UA_cubicParabola
>> * UA_parabola4
>> * UA_clothoide
>> * UA_WienerBogen
>> * UA_BlossBogen
>> * UA_Sinusoide
>> * UA_Cosinusoide
>> * UA_other
>> * UE, which marks the end of the transition curve.
>>
>> [...]
>
> Instead of the abbreviations 'UA' and 'UE' that are derived from the
> German terms "Übergangsbogenanfang" and "Übergangasbogenende", it is
> suggested to use the English driven abbreviations 'TS' (Tangent -
> Spiral) and 'SC' (Spiral - Curve).
>
> [...]

here comes the proposed solution for the transition curve problem:

A new attribute named "geometryElementDescription" has been added to the
element <radiusChange>. It is an enumeration parameter, which provides
the following entries that enable a more detailed description of
transition curves:

* TS_cubicParabola
* TS_parabola4
* TS_clothoide
* TS_WienerBogen
* TS_BlossBogen
* TS_Sinusoide
* TS_Cosinusoide
* SC
* (any other)

As already mentioned, the abbreviations TS (Tangent - Spiral) and SC
(Spiral - Curve) describe the points at the beginning and at the end of
the transition curve.

The modifications have been implemented for railML 2.3 with SVN revision
616. For more details, see the Trac ticket [1].

[1] http://trac.railml.org/ticket/251

Best regards

--
Christian Rahmig
railML.infrastructure coordinator
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