Different properties from same IFC model

Question

I uploaded an IFC model to a BIM360 project and then I used the model derivative API to extract properties.

I uploaded the same model to a Forge bucket (connected to a Forge trial account), then I traslated the model to SVF2. The properties extracted using the same API are different from the ones extracted from the BIM360 model.

Example:

From BIM360

{
            "externalId": "a",
            "name": "LaS_Progetto ANCHOR_DETACHED_VARCO PONTE DEI MILLE_send.ifc",
            "objectid": 1,
            "properties": {
                "IFC Properties": {
                    "IFC Application Name": "Autodesk Revit 2021 (ENG)",
                    "IFC Application Version": "2021",
                    "IFC Schema": "IFC2X3",
                    "IFC Time Stamp": "2022-06-10 15:31:22 +00:00",
                    "Name": "IFC Properties"
                },
                "Item": {
                    "Hidden": "No",
                    "Icon": "File",
                    "Material": "",
                    "Name": "LaS_Progetto ANCHOR_DETACHED_VARCO PONTE DEI MILLE_send.ifc",
                    "Required": "No",
                    "Type": "File",
                    "Unit": "Meters"
                },
                "Location": {
                    "Elevation": "0.000 m",
                    "Latitude": "44.414",
                    "Longitude": "8.919",
                    "Name": "Location Data",
                    "ProjectLocation": "Default Site",
                    "Timezone": "1.000"
                },
                "Project": {
                    "IfcApplicationName": "Autodesk Revit 2021 (ENG)",
                    "IfcApplicationVersion": "2021"
                }
            }
        }

From Forge Autodesk

{
            "externalId": "a",
            "name": "LaS_Progetto ANCHOR_DETACHED_VARCO PONTE DEI MILLE_send.ifc",
            "objectid": 1,
            "properties": {
                "Item": {
                    "GUID": "0b0f2a01-1175-5780-810f-23d90f79b96a",
                    "Hidden": "No",
                    "Icon": "File",
                    "Material": "",
                    "Name": "LaS_Progetto ANCHOR_DETACHED_VARCO PONTE DEI MILLE_send.ifc",
                    "Required": "No",
                    "Type": "File",
                    "Unit": "Meters"
                }
            }
        }

Maybe could be related to SVF2 format retrieves missing or incorrect data from Model Derivative on IFC and RVT

Thanks

Edit:
the problem is related to the options passed to the translate API of Model Derivative. We miss the conversionMethod option. If we set this field to "v3" the properties are the same.

Hi, yes, BIM360 uses v3 conversion method by default for new files uploaded to Docs. For existing IFC files, will keep using the modern one. — Eason Kang, Aug 03 '22 at 08:39

score 0 · Answer 1 · answered Aug 03 '22 at 08:44

BIM360 uses v3 conversion method by default for new files uploaded to Docs. For existing IFC files, will keep using the modern one.

But if you didn't specify any conversion method while calling POST job, model derivative API will use the legacy one by default.

Different properties from same IFC model

1 Answers1