GantryMechanicalDesign Parameter

The GantryMechanicalDesign parameter defines Decoupling Control behavior of a gantry. It specifies if the gantry is Rigid (value=0) or Flexible (value =1). In a classic H-bridge gantry design, the gantry is Flexible if it has a degree of freedom to allow yaw rotation of the Theta gantry axis. It is Rigid if the mechanical design does not have a degree of freedom for yaw motion. This parameter must be set to the same value on both gantry axes.

The restrictions that follow apply to the Theta axis on Rigid gantries:

• You cannot command motion to Theta.
• You cannot set position offsets on Theta.
• Theta cannot be a spindle.
• Theta cannot be an axis that is synchronized to IFOV with the IfovSetSyncAxes() AeroScript function.
• Theta cannot be a transformation output axis.
• Theta cannot be a gearing or camming follower axis.
• Theta cannot be part of a joystick axis group.
• Theta cannot be used with filters or command shaping.
• Theta cannot be a normalcy axis.

The behavior that follows applies only to Rigid gantries:

• The R and Theta axes are enabled and disabled at the same time.
• The controller automatically does alignment moves on the Theta axis during Enable(). The alignment move commands Theta to a position of 0 if Theta has a nonzero value and the gantry has been previously homed.