Geometry

While the time these days is spent refining the design given physical realities,  much attention must be paid to the basic design.

In that vein, I am overdue in presenting the basic geometry and the thought process behind it.

Let us start with a basic representation of the trailer:

The horizontal line is 15" above the top edge of the trailer, while the vertical line is approximately 1/3 of the way back from the front (right.)

Next we need to spring two ellipses that share the axes shown above.  The first one uses the horizontal axis as its major axis, and the vertical as its minor.

The second ellipse uses the same major/minor axes, but the length of the major axis is much shorter while the minor is the same as the first ellipse.

Now the excess gets trimmed, and we see the basic profile of the trailer with the aft portion tracing the large ellipse, and the forward portion tracing the smaller.

The result is one continuous curve created from the combination of the two ellipses.  Cleaning up the drawing and adding a couple details results in this view:

Note that the window and door are balanced on either side of the vertical axis, and the horizontal axis will become a "waist line" in the aluminum cladding.