I started to look at this in more detail, but I'm a little puzzled (not unusual!). Does a straight section meet a curved section at a tangent to the curved section or not? I assumed it would, but then the heights don't seem to match your picture (I could have calculated them incorrectly of course!). Also, is the vehicle really 12 ft long? This seems very long in comparison to some of the section lengths. Does it have wheels front and back, or is it a flat surface in contact with the surface?
Alan