Lateral Friction Coefficient - Nondimensional Force

[Biro]

Good morning.

I'm new here, My name is Jean and I'm from Conservatoire National des arts et métiers - Paris.

I'm studying RCVD to treat our tire data and to understand a little bit more.

In chapter 14 (Equation 14.1), there is an equation that I didn't understand very well

F(bar) = Fy/Mu*Z

Where:

F(bar) = Normalized lateral force
Fy = Lateral force
Mu = Lateral Coefficient friction
Z = Load.

My problem is that I don't have an only C.o.F because its change with the load, so If I do Fy/Fz to obtain the C.o.F and after that
replace this value in my first equation, it will be Always 1.

I can use the normalized force as Fy/Fy1 (peak on that load) but I won't be able to find the Mu to use in another equation lately.

Should I use the C.o.F in the linear range (for small slip angles) ?
Should I use the Peak of C.o.F ??

I know that is a Basic question, but I'm starting now, and I'm a little bit unprepared.


If somebody can help me, I'll be very grateful


Thanks a lot in advance.

PS* = Sorry about my english skills, English is not my mother tongue and I really tried to be very polite in this message.

[Edward M. Kasprzak]

Biro, welcome to the forum!

Mu is Fy1/Fz (using your "Fy1" definition). You are correct that Mu varies with Fz, and that Fy/Fy1 always gives a peak of 1. Please see RCVD Figure 14.1--all the nondimensional forces have peaks at plus or minus 1. You are doing it correctly. As you change the load, just remember to update your Mu value.

[Biro]

Hi, Edward.

Thank you, I hope to learn a lot here.

Thank you for your reply, that's helped me a lot.