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Guidance Control in Detail
English, Revision 07, Date: 07.03.2018
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and the feed forward control. If the steering controller is correctly set, 80% of the cal-
culated steering angle results from the feed forward control (dependent on the driving
conditions). Only the remaining percentage of 20% are provided by the feed back
control / regulator.
2.1.4.1
Feed Forward Control
Figure 11
Feed forward control
The feed forward control calculates a steering angle that keeps the vehicle on the
track. If the three-wheeler described is e.g. driven on a circle, the feed forward control
calculates a steering angle, that adjusts the steered wheel tangentially towards the
track. In an ideal situation the vehicle would exactly drive around this circle.
2.1.4.2
Feed Back Control
The feed back control steers the vehicle back to the intended course. At first the error
in the vehicle position will be determined.
Figure 12
Feed back control
This error consists of two parts: The error of the angle and the lateral deviation.
The steering angle is calculated in such a way that the steering wheel points towards
a point within the intended course in front of the vehicle. The distance between this
point and the center of the rear axis consists of one fix and one variable (velocity de-
pendent) component.