Slip and slide angle, contact patch rotation speed

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pajkul
pajkul
0
Joined: 08 Jun 2011, 20:45

Slip and slide angle, contact patch rotation speed

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Hi!
I thought it it the proper place to ask such questions, so look at this website: http://www.mgf.ultimatemg.com/group2/su ... _angle.htm

It says: What changes a slip angle into a slide angle? Excessive slip angles!!! That is, a slip angle is so called because the part of the contact patch that is to the outside of your turn is moving faster than the wheel itself is in the direction it (the contact patch) is pointing while the part on the inside is moving more slowly. (Exactly like camber thrust.) Since the outside part is moving faster than the tyre it must be slipping. The inside part is gripping better than it would if moving in a straight line. For this reason the contact patch 'walks' itself into the turn.

I thought otherwise, as when taking a turn, the tyre gets deformed in such a way that the vertical weight transfer of the car to the ground is limited if there's nothing over it; the normal force should be higher over the yellow area http://imageshack.us/photo/my-images/822/kbz12.jpg

pajkul
pajkul
0
Joined: 08 Jun 2011, 20:45

Re: Slip and slide angle, contact patch rotation speed

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See page 8. The tyres, in my opinion, are rotating toward us and turning to our right hand side. http://www.engr.colostate.edu/pts/Job/U ... deling.pdf

It shows that the grip on the outer side of the contact patch is higher. So the slipping part is the inner one (of the contact patch).

munks
munks
2
Joined: 20 May 2011, 20:54

Re: Slip and slide angle, contact patch rotation speed

Post

pajkul wrote:What changes a slip angle into a slide angle? Excessive slip angles!!! That is, a slip angle is so called because the part of the contact patch that is to the outside of your turn is moving faster than the wheel itself is in the direction it (the contact patch) is pointing while the part on the inside is moving more slowly. (Exactly like camber thrust.) Since the outside part is moving faster than the tyre it must be slipping. The inside part is gripping better than it would if moving in a straight line. For this reason the contact patch 'walks' itself into the turn.
This is quite possibly the worst description of slip angle I've ever seen.