...
These steps were written for ANSYS 17.1 - the process should remain similar in more recent version of ANSYS.
Reference Geometry
In solidworks, create a 3D sketch of the chassis, with only line elements. Save the solidworks as an IGES file. When saving an IGES file, open up "OPTIONS" and make sure that "Export Sketch Entities" is selected, other wise you will be unable to save the 3D sketch as an IGES file.
...
Now you should have the 3D sketch imported and showing in the Design Modeler.
Creating Tube Profiles
Under "CONCEPT" in the menu, mouse over to "CROSS SECTION" and select the type of element you would like to create. For our purposes we are using "circular tube" and "rectangular tube".
After you have added the cross sections, under "CROSS SECTIONS" in the design tree, click on the tube profiles to define the tube sizes.
Assigning Tube Profiles to Bodies
in the design tree, select an individual element. In the details, under the cross section field, select the cross section profile you would like to set the element to.
Creating a Multi-Body Part
To create a multi-body part, highlight all the line bodies in the design tree, right click, and select "Form New Part".
...