Dynamic weight measurement.

[TomC]

You getting complicated for a very simple solution. Electronic on board scales are made for trucks. The most accurate are the ones that work with a complete air suspension truck (including the front axle). Since most buses (except Eagles) have front and rear air suspension, setting up the scale won't be much of a problem. But-I don't know why you think you need that.
Loading the bus up with water, fuel, people and all the stuff you need then weighing at the truck stop will get you the axle weights for proper tire inflation. As to being over weight, I know on my bus, I weigh in at 31,000lbs (10,500lb front, 20,500lb rear). Considering the bus has a 36,000lb gvw (13,000lb front, 23,000lb rear) I'm 5,000lb away from full capacity. I wouldn't stress too much on overloading the bus. Good Luck, TomC