Automobile handling no relation Yaw and pitch angular inertia (polar moment)
Factors that affect a car's handling
Weight distribution
Centre of mass height
The centre of mass height, also known as the centre of gravity height, or CGZ, relative to the track, determines load transfer (related to, but not exactly weight transfer) from side to side and causes body lean. When tires of a vehicle provide a centripetal force to pull it around a turn, the momentum of the vehicle actuates load transfer in a direction going from the vehicle's current position to a point on a path tangent to the vehicle's path. This load transfer presents itself in the form of body lean. In extreme circumstances, the vehicle may roll over.
Height of the centre of mass relative to the wheelbase determines load transfer between front and rear. The car's momentum acts at its centre of mass to tilt the car forward or backward, respectively during braking and acceleration. Since it is only the downward force that changes and not the location of the centre of mass, the effect on over/under steer is opposite to that of an actual change in the centre of mass. When a car is braking, the downward load on the front tires increases and that on the rear decreases, with corresponding change in their ability to take sideways load.
A lower centre of mass is a principal performance advantage of sports cars, compared to sedans and (especially) SUVs. Some cars have body panels made of lightweight materials partly for this reason.
Body lean can also be controlled by the springs, anti-roll bars or the roll center heights.Yaw and pitch angular inertia (polar moment)
Unless the vehicle is very short, compared to its height or width, these are about equal. Angular inertia determines the rotational inertia of an object for a given rate of rotation. The yaw angular inertia tends to keep the direction the car is pointing changing at a constant rate. This makes it slower to swerve or go into a tight curve, and it also makes it slower to turn straight again. The pitch angular inertia detracts from the ability of the suspension to keep front and back tire loadings constant on uneven surfaces and therefore contributes to bump steer. Angular inertia is an integral over the square of the distance from the center of gravity, so it favors small cars even though the lever arms (wheelbase and track) also increase with scale. (Since cars have reasonable symmetrical shapes, the off-diagonal terms of the angular inertia tensor can usually be ignored.) Mass near the ends of a car can be avoided, without re-designing it to be shorter, by the use of light materials for bumpers and fenders or by deleting them entirely. If most of the weight is in the middle of the car then the vehicle will be easier to spin, and therefore will react quicker to a turn.
no relation