Configuration of IN_POSITION and DONE Events

Configuration of IN_POSITION and DONE Events
after STOP or E-STOP Events

Two fields, settleOnStop and settleOnEstop are incorporated into the MPIAxisInPosition{} structure. These fields control the generation and use of IN_FINE_POSITION, and DONE status bits and events. A value of FALSE in these fields causes the IN_FINE_POSITION to be held false after STOP (or E-STOP) events and DONE to be based solely on command velocity (i.e. DONE is true as soon as the command velocity reaches 0). A value of TRUE in these fields causes IN_FINE_POSITION and DONE to be calculated in the same manner as that for normal motion, except that the position where the command velocity reaches zero is used for a target rather than the original Target Position.

The following table shows the generation of these status bits with settleOnStop (settleOnEstop) = FALSE (the default value):

Motion Status	After S-Curve or Trapezoidal Move	During Velocity Move	After STOP (E-STOP)	After ABORT)
IN_FINE_POSITION	Based on target distance (see note 3)	FALSE	FALSE	FALSE
IN_COURSE_POSITION	Based on target distance	FALSE	FALSE	FALSE
AT_TARGET	TRUE when command = target	FALSE	FALSE	FALSE
DONE	TRUE if both TC and IN_FINE_POSITION are true	FALSE	TRUE when command velocity = 0	TRUE

The following table shows the generation of these status bits with settleOnStop (settleOnEstop) = TRUE:

Motion Status	After S-Curve or Trapezoidal Move	During Velocity Move	After STOP (E-STOP)	After ABORT)
IN_FINE_POSITION	Based on target distance (see note 3)	FALSE	Based on position error (see note 1)	FALSE
IN_COURSE_POSITION	Based on target distance	FALSE	FALSE	FALSE
AT_TARGET	TRUE when command = target	FALSE	FALSE	FALSE
DONE	TRUE if both TC and IN_FINE_POSITION are true	FALSE	Same as IN_FINE_ POSITION	TRUE

NOTE 1: IN_FINE_POSITION is based on four criteria:

The trajectory has completed (see note 2).
command position - actual position < fine position tolerance.
Target velocity - actual velocity < velocity tolerance (the default setting for velocity tolerance so large that this criteria is ignored).
The above three criteria have been satisfied for the duration specified by the settling time parameter.

NOTE 2: The reference to "TC" above refers to TRAJECTORY_COMPLETE, an internal status that is set when all of the current motion segments (frames) have completed.

NOTE 3: The criteria used for calculation of IN_FINE_POSITION after s-curve or trapezoidal motion has changed to the following: (This is the same as the MPI-1 criteria.)

The trajectory has completed (see note 2).
target position - actual position< fine position tolerance.
command velocity - actual velocity < velocity tolerance (the default setting for velocity tolerance so large that this criteria is ignored).
The above 3 criteria have been satisfied for a duration specified by the settling time parameter.

Return to MPIAxisInPosition.