lateral load transfer

[abhidr312nav]

hey guys...
actually i am stuck in a conceptual problem regarding lateral load transfer.
when we have no springs then i assume the tire will completly leave ground as body tries to roll but since no spring this should happen.
1. what we call it load transfer effect due to sprung mass inertia force.

now, when spring is there what i imagine, its spring that not let case I take place....now body wants to roll and it does. but the effect of case I is still there and cant be seen....

now if conceptually we think we should nott add load transfer due to roll moment ( caused by springs) and spring mass inertia force and unsprung mass inertia force...to calculate total load transfer.....while books are doing it...( even millikan).....
please explain this thing where i thinking wrong.....
please also suggest explanation of millikans method ( chapter - ride and roll analysis, simplified second case example, roll analysis)......

[abhidr312nav]

hey guys...
actually i am stuck in a conceptual problem regarding lateral load transfer.
when we have no springs then i assume the tire will completly leave ground as body tries to roll but since no spring this should happen.
1. what we call it load transfer effect due to sprung mass inertia force.

now, when spring is there what i imagine, its spring that not let case I take place....now body wants to roll and it does. but the effect of case I is still there and cant be seen....

now if conceptually we think we should nott add load transfer due to roll moment ( caused by springs) and spring mass inertia force and unsprung mass inertia force...to calculate total load transfer.....while books are doing it...( even millikan).....
please explain this thing where i thinking wrong.....
please also suggest explanation of millikans method ( chapter - ride and roll analysis, simplified second case example, roll analysis)......

[Edward M. Kasprzak]

I think you are having a "cause and effect" kind of conceptual issue. Note that lateral load transfer does not require body roll. Body roll is a common consequence of lateral acceleration, depending on the relative locations of the center of gravity and the roll axis, along with the roll stiffness. The first step is to convince yourself that the total amount of lateral load transferred is independent of body roll.

Suppose you replace your springs with solid links which, for all intents and purposes, we can consider "rigid". The same amount of lateral load transfer will occur (ignorning the lack of lateral CG motion), and any body roll will now be solely due to tire deflection (or chassis flex). If you replaced the tires by steel railroad wheels you'd still get the same lateral load transfer for a given lateral acceleration, just without the body rolling on the tires.

Whatever the design, some of the lateral load transfer is taken by the springs (roll stiffness) and some directly through the suspension (roll center effect). The total is always the same, though, for a given lateral acceleration--see section 18.4 of RCVD.