Elmo HARmonica, HARSFEN0602 12.1.6.3 Motion Management

HARSFEN0602
The speeds in the table are limited to +/- 23
2
counts/second.
The times in the table are in the range [1,255] msec.
If the position feedback sensor counts modulo, the PVT data must be so that the range of the interpolated
data is [-XM...XM-1] (Set YM instead of XM here and in the next sentences if UM=4). Interpolated results
in the ranges [-XM...-XM/2-1] or [XM/2...XM-1] will be folded modulo XM to the sensor range of [-
XM/2...XM/2-1]. Interpolated points out of the range [-XM...XM-1] will be clipped by the Stop-Manager,
refer the section on the "Stop management".
12.1.6.3 Motion Management
In the PVT mode, the Amplifier manages a “read pointer” for the PVT table.
When the read pointer is N, the present motion segment starts at the coordinates written at the Nth row of the
table, and ends at the coordinates of the (N+1) row4.
When the time period specified by QT[N] elapses, the N segment is done, the Amplifier increments the read
pointer to N+1, and reads the N+2 PVT table row to calculate the parameters of the next motion segment.
The user does not have to use the entire PVT table for a given motion.
The use of the PVT table is defined by the following parameters:
Parameter Use
MP[1] The lowest valid row of the PVT table
MP[2] The highest valid row of the PVT table
MP[3] A bit field.
Bit 0 is:
0: Motion is to stop if the read pointer reaches MP[2]
1: Motion is to continue when the read pointer reaches MP[2]. The next
row of the table is MP[1].
Bit 1 is:
0: PVT motion not expected to terminate. Issue an exception if PVT
motion terminates.
1: PVT motion expected to terminate. When all the data in the PVT table
has been used, exit the PVT mode to the Idle mode without issuing an
Emergency object.
Table 12-7 – PVT Motion Parameters
The flow chart of the basic PVT mode is depicted below. The flow chart assumes that the commands
PV=N;BG; were entered, with 64N1 .
4 The PVT mode may be cyclical, according to MP[3] – please refer the explanations below. In that case N+1 must be
interpreted in the modulo sense.