ElmoMC SimplIQ Software Manual - Manual (Page 143)

SimplIQ Software Manual The Position Reference Generator
MAN-SIMSW (Ver. 1.4)
11-2
Command Mode
ST
Idle: ST stops any motion.
PA PTP: PA=n specifies a PTP motion, to absolute position n counts.
JV Jog: JV=n specifies a jog motion, at speed n counts/second.
PT PT: PT=n specifies a PT motion, beginning from the nth item in the PT
data table.
PV PVT: PV=n specifies a PVT motion, beginning from the nth item in the
PVT data table.
Table 11-1: Software Motion Mode Commands
11.1.1 Switching Between Motion Modes
The ST command can be used for stopping at any time. The drive will decelerate the
position or velocity reference until it reaches a full stop.
PTP and jog motion commands can be sent anywhere, at any time. The drive will
calculate the path to be followed so that the desired speed or position is reached, subject
to the acceleration limits. PTP and jog motions can even be initiated during PVT or PT
motion. Care must be taken, however, if the smooth factor (SF) is nonzero. Upon
switching from interpolated motion to PTP or jogging, the PTP or jogging will start
unsmoothed, with smoothing gradually building up, until after SF milliseconds, the
motion is fully smoothed.
Care is also required when switching to tabulated (PT and PVT) motion modes. These
modes should be started only when the motor is at a complete stop (MS=0 or MS=1), at
the exact position specified as the first point for the PT or PVT. If the motor is not totally
stopped at the correct start position, the software reference will jump. The command to
the position controller will attempt to catch up with the PT or PVT motion, using the SD
acceleration (refer to
section 11.3 ).
11.1.2 Comparing PT and PVT Interpolated Modes
The following tables compare PT and PVT motion modes.
Feature PT PVT
Motion buffer length 1024 64
Position points in one CAN
message 2 1
Speed command calculation Automatic, by third-order
interpolation Specified by user
Acceleration command Automatic, by third-order
interpolation Automatic, by third-order
interpolation
Time between user data
points Fixed multiple of the
1 - 255 controller sampling
times. Cannot be changed
on-the-fly. Specified by user
independently for each
motion interval, in msec.
Range: [1…255] msec.