Smart Flat Ride Tuning

Abstract

Flat ride is the condition that the unpleasant pitch oscillation of the vehicle body turns into more tolerable bounce oscillation, when a car hits a bump in forward motion. Based on experimental results, Maurice Olley discovered and introduced two conditions for flat ride:

• 1. The radius of gyration in pitch should be equal to the multiplication of the distance from the mass centers $a_{1},a_{2}$ of the front and rear wheels of the car (${r}^{2} = a_{1}a_{2}$).

• 2. The rear suspension should have around 20% higher rate than the front. The equation ${r}^{2} = a_{1}a_{2}$ makes the car to be considered as two separated uncoupled mass-spring systems of front and rear suspensions.

In this chapter, we will analytically review the flat ride conditions and provide design charts to satisfy the required conditions. The nonlinear practical model of shock absorbers modifies the conditions which were based on linear models.