Unitweight is not handled as an SI unit

[glenworrall]

Is your feature request related to a problem? Please describe.
This feature is related to imperial units from an Openbuilding Designer workset, I am not sure if this is also manifested on Revit projects.

The workset is for a specific project Workset. etc, but I think will manifest itself for all imperial OBD worksets.

This query
select ecclassid, structuralframingcommon_sectionname, StructuralQuantities_Length, StructuralQuantities_UnitWeight, StructuralQuantities_LengthXUnitWeight, * from WorkSet_<user_hidden>.Steel__x0020__Beam limit 1
returns these values
W18X40, 9.02336808483617, 40, 537.1355529347727
So it would seem that some structural quantities do not register their units correctly

select pd.name, qd.name, qd.PersistenceUnit from meta.ECPropertyDef pd LEFT join meta.KindOfQuantityDef qd on pd.kindofquantity.id = qd.ecinstanceid where pd.name like 'StructuralQuantities%' and class.id = 0x119c

Unit Weight is blank … and in the above is lbs/ft ie W18X40 is 40lbs per linear foot.
Therefore 9.023 = ~ 29’ 7” (29.6) * 40 = 1184lbs … = ~538 kg
Ie
While lengthxunitweight is correct and is in SI, the basis for the calculation unitweight is not handled as an SI unit and is left as an imperial measure.

Can this be handled correctly so the unit weight is handled as kg ?

[glenworrall]

On a related note ... it would be great if Lengthxunitweight was also published to a QTO.weight aspect ... ie a common table to identify the weights of elements.

[hl662]

I was able to get my hands on a QA iModel with the relevant property and schemas. Colin helped me with the query looking into the propertyDef for unit weight, we observed that this property doesn't have a KindOfQuantity assigned to it. Without a KindOfQuantity, this property isn't unitized, and the persisted value isn't mapped to a unit, much less an SI Unit (one relevant unit would be Units.KG as that is SI). With the property not being unitized, I suspect the value being persisted in the iModel is the value coming from the source file and is not transformed into an appropriate value.

@jffmarker I don't know the inner workings of the connector for OBD, are you or someone from connectors able to check how the connector populates the data?

PS: Query i put in imodel console:
SELECT * FROM meta.ECPropertyDef WHERE Name LIKE '%StructuralQuantities_UnitWeight%'

[jffmarker]

Let me start an e-mail thread since I don't know the OBD developers' GH handles.

[jffmarker]

Update from Pradnya in e-mail:

It seems that the Unit Weight definition is not correctly defined in the current OBD connector, but the same has been addressed in the next gen connector.