文档介绍：Available online at hanism
and
Machine Theory
Mechanism and Machine Theory 43 (2008) 57–67
ate/mechmt
Roll steer minimization of McPherson-strut suspension
system using ic algorithm method
Hosein Habibi, Kourosh H. Shirazi *, Mohammad Shishesaz
Mechanical Engineering Department, Chamran University, Ahvaz, Iran
Received 17 January 2006; received in revised form 14 August 2006; accepted 5 January 2007
Available online 13 March 2007
Abstract
In this research the roll steer of a front McPherson suspension system is studied and the design characteristics of mech-
anism are optimized using ic Algorithm method. The roll steer is defined as undesirable and uncontrollable changes
in the steering angle of the steered wheels during the rolling action of the vehicle body due to cornering maneuver or asym-
metric bumps. The roll steer affects handling and dynamic stability of the vehicle due to variation of the angles of the wheel
and the suspension links (. camber, caster and toe). However these changes cause other problems. In this paper, in con-
junction with the study of three-dimensional kinematic model of McPherson mechanism, a set of mathematical equations
are derived to determine the suspension behavior of a typical vehicle through the rolling. The kinematic analysis is followed
by an optimization process using the ic algorithm method to determine the optimum length and orientation of the
mechanism’s members to minimize the variations of the toe, the camber and the caster angles. However the variations can-
not be expressed by closed form functions, thus a performance index is defined in the integral form which expresses the
overall variations of the main parameters in the whole range of rolling of the body. It is shown that the ic algorithm
can be effectively used in optimization of three-dimensional behavior of such spatial linkages in which the performances
indices have no closed form with many variables under the non-smooth constrain