1 reply to this topic

[Sisyphus]

For the past few years, the upper front suspension arms in head-on photos of F1 cars have looked peculiar to me. 

 

Traditionally, the inboard top front suspension arm pivot would be closer to the ground than the outboard top pivot.  This causes camber to go more negative on the loaded outboard side as the chassis rolls and thus give the tires more grip.

 

But the photos I've seen the last few years, particularly with Mercedes and Red Bull (but I think probably with all of them) that the inboard pivot seems to be higher than the outboard pivot which will cause the camber to become more positive.

 

Can someone explain what is going on?  Is this an optical illusion--I think flexures are now used instead of rod ends but I don't see why that would change what the tire wants?

 

Thanks.

[gruntguru]

An image illustrating your point would help.

 

Angle of the top arm in front view is only half the picture. It is actually the angle between top and bottom arms that determines camber change at a given "instant". Extend the line passing through the top arm spherical joint centres until it meets the equivalent line for the lower arm. If the intersection lies outside the track, the camber is increasing (towards positive) in bump. If inside the track camber will go negative.

 

Obviously the intersection point may move when the suspension travels more than an infinitesimal amount.