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3.4. DIRECTIONAL CONTROL
CHAPTER 3. CONTROL SYSTEMS
Figure 3.5: Diagram of the bicycle model representation of the vehicle.
cle CG location of a=1.12m and b=1.494m, and a typical cornering coefficient obtained
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from Milliken of 10000N/rad [23]. The resulting value, K=0.001 rad∗s
indicates underm2
steer behavior, implying that the vehicle will tend to increase its path curvature as speed
increases. This effect would be expected for a passenger vehicle such as an Escape. From
the curvature response equations, it can be seen that the two primary variables affecting
path curvature are steer angle, δ , and forward velocity, V, and that the steer angle is the
primary contributor.
To obtain the curvature rate response, it is necessary to take the derivative of the curvature response equation with respect to time. Performing this differentiation symbolically
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