LAC-1 single axis controller manual

SMAC
LAC-1 Technical Reference Manual
4.3 Motion Commands
Motion Commands are those commands that involve or cause the actual movement of a
servo. Any position mode (PM) based motion will be carried out using a trapezoidal velocity profile
with the maximum velocity determined by the Set Velocity (SV) command. The acceleration and
deceleration are the same and both are determined by the Set Acceleration (SA) command.
During the execution of a Position Mode based motion, the target position (MA or MR) and
the maximum velocity (SV) may be changed at any time, however, changes to the acceleration
(SA) will be ignored. If a velocity mode (VM) based motion is under way, the maximum velocity
(SV) and the acceleration (SA) may be changed at any time. During this type of motion, the target
position will continuously be set equal to the current optimal position. If a torque mode (QM) based
motion is under way, the torque setting (SQ) may be changed at any time. During this type of
motion, the target and optimal positions will continuously be set equal to the current real position.
In either PM, VM or QM, a Stop (ST) or Abort (AB) command will cause motion for the specified
servo axis to cease. If a servo axis is in Position Mode (PM) and is commanded into Velocity Mode
(VM), the motion will continue (only with no target destination) at the current maximum velocity set
by the Set Velocity (SV) command. If a servo axis is in PM or VM and commanded into Torque
Mode (QM), the servo output will be reduced to zero, and the unit will be placed in QM. If a servo
axis is in VM and commanded into PM, the servo will be stopped at the current acceleration rate
and placed into the PM mode. If a servo axis is in QM and commanded into VM, it will attempt to
instantly assume the last known maximum velocity and remain in VM. If a servo axis is in QM and
commanded into PM, the output will be reduced to zero, and the servo will begin station keeping
in PM.
Command: AB -- Abort Motion --
This command causes an emergency stop. The servo stops abruptly but leaves the servo
control loop enabled. The target position is changed to be equal to the present position. The
command is used for stopping an undesired motion.
Related Commands: ST
Command: CI -- Capture on Index --
This command causes the position counter for the servo to be stored in the internal variable
HREG upon receipt of an index pulse. For more information on HREG, see the Register Commands
and the listing of the internal variables.
Related Commands: FI, WI
Command: DHn -- Define Home --
Argument: -2,147,483,647