Imported scan data sometimes places the world coordinates in seemingly random locations in relation to the part. This can be frustrating when viewing the part and if certain features need to be referenced in relation to something else. This guide will explain how to align the part to the world coordinate system. There is an accompanying video that goes through this process. You can watch it here:
Step 1: Create Planes and Axes
Many times there are specific features that represent the origin. In this demonstration I selected two holes with a center axis and the outside edge of a front fork from a motorcycle as the origin for my coordinate system. I started by creating a new part in Solidworks. Then imported the mesh from my front fork scan data. Then I used the Create Plane tool in the Xtract3D add-on panel.
Users can click several times on a flat area on the scan data to create plane. I decided to create a plane on the flat area where a hole was located at the bottom of the front fork. Then I created a sketch on that plane and used the Perimeter Circle tool to select points around the edge of the hole and the circle will match the size of the one on the scan data.
I saved the sketch then created a plane on the other side and repeated the sketch process. This left me with two sketched circles that I wanted my axis to go through the center of. On the feature tab I clicked Reference Geometry and then Axis on the drop down menu.
From there I clicked on the center points on both circle sketches and it creates an Axis in between them. This Axis will be crucial to creating the other planes necessary for creating a new coordinate origin. I used the Create Plane tool again the create a plane on the back face of the front fork. I want one axis in my coordinate system to be parallel to this face. Then I selected the Reference Geometry button again but this time selected Plane.
Then I clicked the Axis I previously created as the First Reference and I selected the option Coincident.
Then I clicked on the plane I made on the back of the fork and selected Perpendicular.
This created a plane on the axis that is parallel to the ground and perpendicular to the back. It will end up being my X axis. I repeated this process of selecting Reference Geometry then Plane. This time I selected the Axis as the first reference and the plane I just created as the X-axis as the second reference with the option set to perpendicular. I made the plane on the back of the fork invisible since I am no longer using it. I also made one of the planes that I used to draw the circle invisible and leave the other visible. I am now left with three planes that are all perpendicular to each other, these three planes will be the x, y, and z axes of my new coordinate system. In order to anchor the coordinate there needs to be a point. I have decided to use the center of the sketch of a circle that the plane is still visible since it is the point where all three planes intersect. To do this, I selected Reference Geometry and Point. Then I clicked on the center of the circle and it placed the point there.
Step 2: Create a Reference Coordinate System
Next I selected Reference Geometry and Coordinate System.
I clicked on the point at the center of the circle to anchor the coordinates. Then I clicked on the three planes, assigning them to the axes I would like them to be.
If the axis is point in the wrong direction select the arrows in front to flip it to the opposite direction. Checked the green arrow when done and the reference coordinate are complete.
Step 3: Merge the Reference and World Coordinate Systems
I selected the scan data from the part tree so the whole mesh is selected. Then clicked on the Use Coordinate System button.
I selected the reference coordinates I just made and press the check mark. If I zoomed out I will find that the part is now correctly aligned on the world coordinates. You can delete the reference geometry used to get there.