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This button will turn off Lock and open the Motion Settings window:
Figure 16. Motion Settings Window available through the GuideStar II Tab.
o
Set Target Position
This button will reset the target centers to the current
beam locations. This can be executed without the need to re-acquire the
Motion Matrix.
o
Target Width
is the size of the Outer Target.
o
Inner Target Fraction
Target Width multiplied by the Inner Target
Fraction gives the Inner Target size.
o
Loop Gain
When position Lock is on, and the beam moves outside the
outer target, the motors are commanded to move the beam back to the
Inner Target. The distance to the center of the Inner Target, scaled by the
Loop Gain, is the size of the step taken. This parameter will influence the
dynamic response of the control loop. It is recommended that one start
with the default value and adjust it to achieve a well-behaved (no ringing,
relatively fast) return of the beam to the Inner Target. A higher value will
increase the speed of the loop response but may lead to ringing or erratic
behavior. A lower value will give a well-behaved response but may make
the response to slow. Typically, Loop Gain is set such that the beams are
brought back to their Inner Targets within 2-5 seconds.
o
Inner Gain Fraction
This value will scale the loop gain once the beam is
within the Outer Target.
