Hardware Reference

In-Depth Information

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Frequency (rad/s)

Figure 3.2: Open loop Bode plot with controller given by equation 3.14 with

crossover frequency chosen f
v
= 500 Hz = 3142 rad/s. Solid line: Rigid body

plant of equation 3.12, and Dashed-line: Plant with resonant mode as modeled

by equation 3.13.

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Frequency (rad/s)

Figure 3.3: The Bode plot of the controller G
c
(s) corresponding to Figure 3.2.

andevenpoweramplifier bandwidth which are ignored in equation 3.9 become

prominent when servo bandwidth is increased.

The crossover frequency and thus the servo bandwidth can not be increased

arbitrarily in presence of actuator resonances. The resonance modes of the

actuator add phase lag and limit the achievable servo bandwidth. Methods