A long time ago, in a university far, far away (23 years and 2500 miles counts, right?) I learned that when you exert a side force on a pneumatic tire as it's rolling along, it slips sideways a bit, without actually skidding (it has something to do with flexible sidewalls and where the tread goes with relation to the rim and other stuff that I can't visualize without moving my hands and staring into space and mumbling and generally alarming bystanders).
I learned this from a really neat book for automotive/mechanical engineer types, published in the 1950s -- one of those where the pages with pictures were really thin and shiny and the contrast of the black and white photos was almost surreal. It was old enough that it was mostly about bias-ply tires, but it did mention those newfangled "radial" things as an aside. Great book, but it's a long drive to Worcester MA from Oregon City.
Now I'm working for a customer who wants me to assume that the direction that a car is pointing is the direction that it's actually moving, even when it's going around a corner at a safe but still pretty good clip. I just know that the assumption isn't true, and I'm pretty sure that with normal passenger tires you're not going to make yourself into a cop attractant until the sideslip angle is a good portion of ten degrees -- but I don't know.
Anyone with direct experience? Numbers?
Anyone know any web references? Any titles that I might look under? Library of congress numbers, as a starting place for my search? I'm thinking of traipsing off to Portland State University to dig through their library, but cruddy old automobile tires aren't Green or Digital or Silicon or .com or any of the other technology fads that have swept through Oregon without leaving many jobs behind*. So I'm not sure if there'll be much there.
Thanks in advance.
- The jury is still out on Green, but color me dubious.