PIDWithLag:

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   Creates a PID controller with lag compensation.
   
   Creates a PID controller when there is a lag that you wish to
   approximately compensate. You enter the ideal integrator time constant,
   the damping ratio and undamped natural frequency of the complex pole 
   pair. You then select a range of frequencies about you which to 
   compensate for the lag.

   Type PIDWithLag for a demo.
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   Form:
   y = PIDWithLag( d )
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   Inputs
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   d         (1,1)   Data structure
                     .a    Integrator time constant
                     .zeta Damping ratio
                     .wN   Undamped natural frequency
                     .tau  lag
                     .w    Range of frequencies to minimize lag effect
                     .k    Forward gain (e.g 1/mass or 1/inertia)

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   Outputs
   -------
   y         (:)     .kI   Integral gain
                     .kP   Proportional gain
                     .kD   Derivative gain
                     .mI   Ideal Integral gain
                     .mP   Ideal Proportional gain
                     .mD   Ideal Derivative gain

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Children:

Common: Graphics/NewFig
Common: Graphics/XLabelS
Common: Graphics/YLabelS