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Moog Animatics SmartMotor™ Developer's Guide, Rev. L
Page 582 of 909
MP
Mode Position
APPLICATION:
Motion control
DESCRIPTION:
Request position mode
EXECUTION:
Buffered until a G command is issued
CONDITIONAL TO:
N/A
LIMITATIONS:
N/A
READ/REPORT:
N/A
WRITE:
N/A
LANGUAGE ACCESS:
N/A
UNITS:
N/A
RANGE OF VALUES:
N/A
TYPICAL VALUES:
N/A
DEFAULT VALUE:
This is the default motion mode at power up
FIRMWARE VERSION:
5.x and later
COMBITRONIC:
MP:3 or MP(0):3
where ":3" is the motor address — use the actual address or a
variable
DETAILED DESCRIPTION:
Mode Position (MP), or position mode, is the default mode of the motor. If you ever change
modes, you can return to position mode by issuing the MP command. The mode request is
buffered until a G command is issued.
NOTE:
For a standard position-mode move, the SmartMotor™ requires, at a
minimum, a position target (PT), nonzero trajectory velocity (VT) and a nonzero
positive acceleration/deceleration (ADT).
MP calculates the trajectory to the target position when the G command is issued. The
preceding PT=formula or PRT=formula determines if the move is to be absolute (destination
target set equal to buffered PT value) or relative (destination target set equal to current
trajectory position plus the buffered PRT offset value).
The PID (servo) will be active. The MP mode calculates a trapezoidal velocity profile as a
function of time. This profile is calculated to accelerate, reach a slew speed, and decelerate in
a way so the speed is exactly 0 at the target position. The PID uses this calculated ideal
position (PC) and compares it to the actual position (PA). The PID will apply torque to the
motor to follow this profile with as little error (EA) as possible. Position error is due to basic
physics of friction, inertia, gravity or any other force on the motor.
The G command may be issued at any time, and it may be repeated (particularly in the case
of relative modes with PRT=offset). When repeating the G command in the middle of a move,
the result will depend on the absolute versus relative mode:
Part 2: Commands: MP
