Galil DMC-4040, User Manual

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Using the KS Command (Step Motor Smoothing):
When operating with step motors, motion smoothing can be accomplished with the command, KS.
The KS command smoothes the frequency of step motor pulses. Similar to the command IT, this
produces a smooth velocity profile.
The step motor smoothing is specified by the following command
:
KS x,y,z,w where x,y,z,w is an integer from 0.25 to 64 and represents the amount of
smoothing
The smoothing parameters, x,y,z,w and n are numbers between 0.25 and 64 and determine the degree of filtering.
The minimum value of 0.25 implies no filtering, resulting in trapezoidal velocity profiles. Larger values of the
smoothing parameters imply heavier filtering and smoother moves.
Note that KS is valid only for step motors.
Homing
The Find Edge (FE) and Home (HM) instructions may be used to home the motor to a mechanical reference. This
reference is connected to the Home input line. The HM command initializes the motor to the encoder index pulse in
addition to the Home input. The configure command (CN) is used to define the polarity of the home input.
The Find Edge (FE) instruction is useful for initializing the motor to a home switch. The home switch is connected
to the Homing Input. When the Find Edge command and Begin is used, the motor will accelerate up to the slew
speed and slew until a transition is detected on the Homing line. The motor will then decelerate to a stop. A high
deceleration value must be input before the find edge command is issued for the motor to decelerate rapidly after
sensing the home switch. The Home (HM) command can be used to position the motor on the index pulse after the
home switch is detected. This allows for finer positioning on initialization. The HM command and BG command
causes the following sequence of events to occur.
Stage 1:
Upon begin, the motor accelerates to the slew speed specified by the JG or SP commands. The direction of its
motion is determined by the state of the homing input. If _HMX reads 1 initially, the motor will go in the reverse
direction first (direction of decreasing encoder counts). If _HMX reads 0 initially, the motor will go in the forward
direction first. CN is the command used to define the polarity of the home input. With CN,-1 (the default value) a
normally open switch will make _HMX read 1 initially, and a normally closed switch will make _HMX read zero.
Furthermore, with CN,1 a normally open switch will make _HMX read 0 initially, and a normally closed switch will
make _HMX read 1. Therefore, the CN command will need to be configured properly to ensure the correct direction
of motion in the home sequence.
Upon detecting the home switch changing state, the motor begins decelerating to a stop.
Note: The direction of motion for the FE command also follows these rules for the state of the home input.
Stage 2:
The motor then traverses at HV counts/sec in the opposite direction of Stage 1 until the home switch toggles again.
If Stage 3 is in the opposite direction of Stage 2, the motor will stop immediately at this point and change direction.
If Stage 2 is in the same direction as Stage 3, the motor will never stop, but will smoothly continue into Stage 3.
Stage 3:
The motor traverses forward at HV counts/sec until the encoder index pulse is detected. The motor then decelerates
to a stop and goes back to the index.
DMC-40x0 User Manual Chapter 6 Programming Motion
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