Page 511 - Automotive Engineering Powertrain Chassis System and Vehicle Body

Modelling and assembly of the full vehicle C HAPTER 15.1

ROLL STIFFNESS MODEL – 100 km/h LANE CHANGE
40.0
30.0 Track test __ __ __ __
___________
ADAMS
20.0
Yaw rate (deg/s) 10.0
10.0
0.0

20.0
30.0

40.0
1.0 3.0 5.0
0.0 2.0 4.0
Time (s)

Fig. 15.1-55 Yaw rate comparison – roll stiffness model and test. (This material has been reproduced from the Proceedings of the
Institution of Mechanical Engineers, K2 Vol. 214 ‘The modelling and simulation of vehicle handling. Part 4: handling simulation’, M.V.
Blundell, page 81, by permission of the Council of the Institution of Mechanical Engineers.)

longitudinal direction x, the lateral direction y and the yaw a ij ¼ wheel slip angles (rad)
_
around the vertical axis z. w ¼ yaw rate (rad/s)
The vehicle parameters used in the following model F zij ¼ vertical forces on each wheel (N)
include: ij ¼ position: i ¼ front( f )/rear(r), j ¼ left(l )/
v x ¼ longitudinal velocity (m/s) right(r)
v y ¼ lateral velocity (m/s)
v cog ¼ centre of gravity velocity (m/s) Note that steer angle d and the velocity of the vehicle’s
2
a x ¼ longitudinal acceleration (m/s ) centre of gravity v cog are specified as model inputs.
2
a y ¼ lateral acceleration (m/s ) The relationship between the dynamic vehicle pa-
G ¼ torque around z-axis (Nm) rameters can be formulated as differential equations.
d ¼ steer angle (rad) Most of these can be found in the standard literature.
b ¼ side slip angle (rad) Using formulas by Wong and Will and Z.ak the following

LINKAGE MODEL – 100 km/h LANE CHANGE
40.0
__ __ __ __
Track test

30.0 ___________
ADAMS
20.0
Yaw rate (deg/s) 10.0
10.0
0.0

20.0
30.0

40.0
1.0 3.0 5.0
0.0 2.0 4.0
Time (s)

Fig. 15.1-56 Yaw rate comparison – linkage model and test. (This material has been reproduced from the Proceedings of the Institution of
Mechanical Engineers, K2 Vol. 214 ‘The modelling and simulation of vehicle handling. Part 4: handling simulation’, M.V. Blundell, page 81,
by permission of the Council of the Institution of Mechanical Engineers.)

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