Autodesk Inventor Users

Hi

For the patch i would first create a ellipse surface with a simple extrude or loft command. Then i would crate a spiral surface with a coil command. And for the 3d path use 3d sketch intersection curve command.

This took about 10 minutes. First thing I did was draw a 2D sketch of an ellipse (I dont know what your dimensions are but the principle is still the same) and I put points on the top, bottom, left and right of the ellipse. I also added a horizontal line and a vertical line to use later.

The next thing I did was create a 3D sketch where I included all the points and the horizontal line and the vertical line from the 2D sketch I did earlier. I used this reference geometry to create my frame work for building my helix. (I dont know what your dimensions are but so for instruction purposes I stepped it down in 10" intervals) You can make your lines go the direction you want by using you parallel and perpendicular constraints along with the reference geometry you included earlier.

The third thing I did was create a series of splines with multiple vertices (I used 5 each) to go from the starting point to each of the 4 points I created in the previous step. I used the short construction lines shown in the previous drawing to get the beginning and ending pitch correct by making the spline ends tangent to those lines.

Next I made sure my splines matched the ellipse all the way through by looking at the top view and placing each vertex on the reference ellipse I drew in step 1.

Lastly I looked at the front view and lined all of my vertices up with the tangent lines corresponding to the vertical pitch of my helix.

Just to give a more clear picture of the finished product I swept a square along the elliptical helix I just created. I just did one 360 degree revolution of the helix but if your helix has more than one coil just repeat this as many times as you need.

Thanks very much

you're welcome