Navisworks - Distant Origin Point

3D models should always be located as close as possible to the model's origin point, also known as the 0,0,0 point.

The farther away the model is from the origin point, the less geometric accuracy it has. This can result in a lot of weird mathematical bugs: broken geometry, disappearing objects, zoom errors, and objects that move around on their own. When viewing with InsiteVR, having a model very far away from the origin can cause graphic issues and performance issues.

By the time models have been aggregated in Navisworks, it's usually too late to tell subcontractors to move their models closer to the 0,0,0 point. We will look at two solution to solve this problem.

Temporary Solution

The temporary solution is to find the 0,0,0 point of the Navisworks environment and to move all models there manually. This is harder than it sounds because Navisworks does not seem to have an option to display the 0,0,0 point. To get around this, we can import a simple CAD drawing that has a large circle around the 0,0,0 point.

Append the attached file "Origin.dwg" to find the origin point in Naviswork. It will show up as a large circle. Save a backup copy of your Navisworks file. Press "Page Up" on the keyboard to "Zoom All". This should display your mode and the new circle that represents your Origin Point.

For each other model in the Selection Tree menu, right-click and use the "Units and Transform" dialog box. Through trial and error, manipulate the origins of the model to move them closer to the 0,0,0 point of the "Origin.dwg" file. Use the same transformation of origins on all other models.

Long Term Solution

The long term solution is to get everyone on the team to use industry best-practices and to locate their model close to the 0,0,0 point. Oftentimes, architects will use the intersection of the lower left (South West) structural grid line as the location for the project origin point. We do not recommend changing the location of the origin point after the project has started, it is very important to set this data at the very beginning of the project and to make it part of the firm's workflows and standard BIM procedures.

AutoCAD Origin

Finding the origin point in AutoCAD is fairly easy. When you do a ZOOM ALL command (press Z <spacebar> and A, you should see the UCS icon. The UCS stands for User Coordinate System and represents the 0,0,0 point.

If the UCS does not show up, type UCSICON, <spacebar> and ON.

If you still don't see the origin, draw a line starting from the 0,0,0 point by typing L, <spacebar>, 0,0 and then clicking around the location of your current drawing. If you do a Zoom All again ( Z <spacebar> and A) , it will show your model and the origin point.

Once you've found the origin point, you can unlock and unfreeze all the drawing layers and drag them towards the origin point.

Alternatively, newer AutoCAD versions will allow you to drag the UCS instead of dragging the lines around. This method can prevent errors caused by invisible annotative objects and other advanced AutoCAD functions.

If you are annoyed by the sight of the UCS icon, type UCSICON, <spacebar> and OFF.

Revit Origin

Surprisingly, Revit origins are based on the Survey Point rather than the Project Base Point. Origins in Revit can get complicated so we don't suggest moving the origin unless you have in-depth experience with Revit reference points. Usually, a clear Base and Survey point are defined at the beginning of the project. Therefore, your Model and Survey point best practices procedure should be to place these reference points near the model at the beginning of the project and never move them again.

If you need to change the location of a Survey point midway through a project, the following describes how. First, make sure to communicate with your team to make sure nobody is relying on the Survey point for their data, this will be especially relevant for geoengineers or surveyors on the project. When this is done, go into the base file and reveal the Survey Point through the Visibility/Graphics Override window. To do this, press "VV" and check "Site>Survey Point". Select the revealed Survey Point, make sure the Clip icon does not have a red line through it and move the Survey Point by inserting new X,Y,Z values or dragging it with the arrows. Once again, this is not recommended as it may disrupt the location of linked files, Spot Elevations and Shared Coordinates.

Please keep in mind that is it usually not viable to move the geometry closer to the Survey point since none of the text or line annotations will move the with physical model. This is why we move the Reference Points rather than the geometry.

If you are starting a project in Revit, we recommend identifying the location of the Origin and Survey Point and starting your model near it. To do this, simply use the "Reveal Hidden Objects" button or use the Visibility/Graphics Override window.

A good way to deal with this problem is to have a text annotation pointing to the Origin and Survey point in your office Revit template. This helps employees start the project in the right location from the start of the project.

Problematic Models, Drawings and Blocks

Sometimes a drawing, model or AutoCAD block has a small piece of geometry or a line that is floating many miles away from the drawing origin. This can be hard to track down and fix, especially in embedded autoCAD blocks. There is no simple solution to this issue, but it should not be ignored. If your imported models have a small line or a floating object far away from the rest of the model, it should be hunted down and dealt with in the original drawing or model. Ignoring the problem will cause issue when using "Zoom All" and can cause geometry, scheduling or stability issues.

Conclusion

Placing elements far away from the Origin point can be problematic. If you clarify where the origin point is with your team, you will avoid needless issues before they arise.

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