Racecar Kinematics and Compliance
Kinematics
By definition, kinematics is the branch of mechanics concerned with the movement of objects without reference to the forces which cause motion.
In the context of wheel kinematics, this refers to camber and toe, which are our two key vehicle dynamics parameters. In operation, these can vary as the wheel moves through its operating ranges of motion (compression/rebound travel and steering).
Camber and Toe are an ally for a vehicle dynamicist.
There is a range of tools available to us to define the kinematic behaviour of suspension. The below table shows the primary methods we consider for a double-wishbone system.
Each of these affects the tyre through the methods explained in the previous Wheels & Suspension section. By dynamically altering toe and camber angles, they either work to generate a more optimal slip angle, which enables more lateral force or maximise contact area through camber angle variation.
Designing a geometry that enables precise control over these variables allows the dynamic control needed to maximise the performance of a suspension configuration.
Ackermann geometry is a tool used to place inside and outside steered wheels at optimal slip angles. [Tim Carey]
Camber gain
Camber gain counteracts the effects of rotation at the tyre contact patch as lateral acceleration builds and the outside wheel moves into compression during body roll.
With this additional negative camber, tyre contact area is maximised at all stage...
Source:
racecar-engineering
URL:
http://www.racecar-engineering.com/
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