BS ISO 8855:2011 pdf free download.Road vehicles — Vehicle dynamics and road-holding ability — Vocabulary.
7.1.3 mean steer angle
δ m mean road wheel steer angle average of the left and right hand steer angles (7.1.1) on the same axle
7.1.4 mean kinematic steer angle
δ m , kin mean steer angle (7.1.3), corresponding to a given steering-wheel angle (7.1.8), defined by the kinematics of the steering system in the absence of tyre forces and moments, and vertical wheel-to-body travel, but including static tyre vertical load
NOTE The mean kinematic steer angle may be defined for any steerable axle. It is intended that the position of the axle
be specified.
7.1.5 included kinematic steer angle
δ inc , kin mean kinematic steer angle (7.1.4) of the front axle minus the mean kinematic steer angle of the rear axle
7.1.6 static toe angle
angle between the X V axis and the wheel plane (4.1), about the Z V axis, with the vehicle at rest and the steering in the straight ahead position, where the wheel is “toed-in” if the forward portion of the wheel is closer to the vehicle centreline than the wheel centre (4.1.2) and “toed-out” if it is farther away
NOTE By convention, toe-in is considered a positive angle, and toe-out is a negative angle.
7.1.7 total static toe angle
sum of the static toe angles (7.1.6) on the same axle
7.1.8 steering-wheel angle
hand-wheel angle δ H angular displacement of the steering-wheel measured from the straight ahead position, which is positive for a left turn of the vehicle
NOTE The straight ahead position may be determined dynamically, as the steering-wheel angle which produces zero yaw velocity (5.2.19) under a given set of initial conditions or statically, as the steering-wheel angle corresponding to zero mean steer angle (7.1.3) ( δ m = 0).
7.1.9 Ackermann geometry
steering system kinematics where the Y W axes of the steerable wheels intersect the centre of rotation, for non-zero steering-wheel angles (7.1.8) at negligible lateral accelerations (5.1.12).BS ISO 8855 pdf download.