Half spherical orbiting
Process control by PLC
Down channel | Orbit channel | Escape channel | Escape condition |
Vprog | Vprog, start / stop | Vext | Vext < 0 and |
In half spherical orbiting, the down channel moves at a constant velocity. Another difference compared to star orbiting is that the down geometry has both a sector in the positive radius direction and one in the negative radius direction.
The example program uses the same contour in the down channel as for star orbiting erosion. However, a real-time loop is also used instead of a normal loop. This offers flexibility to increase or decrease the number of loops depending on the progress of the process.
Programing Example

Down channel - half spherical orbiting
% Half spherical orbiting
N0270 #RT CYCLE DELETE [ID =4711 ] ; Define the real-time loops
N0280 #RT CYCLE [ID=4711 SCOPE = GLOBAL]
N0290 $IF V.E.RtLoopEnable != 0
N0300 V.RTG.LOOP.ENABLED = TRUE
N0310 $ELSE
N0320 V.RTG.LOOP.ENABLED = FALSE
N0330 $ENDIF
N0340 #RT CYCLE END
N0350 #FLUSH WAIT
N0360 G19
#RT WHILE
N0410 G01 X0 Y0 Z30 F1000 ; down
N0420 G03 Y30 Z60 J0 K30 ; expand radius in positive direction
N0430 G01 Z70
N0440 G01 Z60
N0450 G02 Y0 Z30 J-30 K0 ; move back to centre
N0360 #OPTIONAL EXECUTION ON [SIMULATE] ; optional change to the next disc position
N0370 #SIGNAL SYN [ID "S-PlanetarySectorReq" CH2] ; signal for orbit channel to move to the next position
N0380 #WAIT SYN [ID "S-PlanetarySectorOk" CH2] ; wait until orbit channel is in position
N0390 #OPTIONAL EXECUTION OFF
N0460 G02 Y-30 Z60 J0 K30 ; expand radius in negative direction
N0470 G01 Z70
N0480 G01 Z60
N0490 G03 Y0 Z30 J30 K0 ; move back to centre
N0500 #RT ENDWHILE
N0550 G01 Y0 F100 ; end machining
N0560 M17
Programing Example

Orbit channel - half spherical orbiting
%L channel_sync
N2000 #SIGNAL SYN[ID "S-PlanetarySectorOk" CH1]
N2010 #WAIT SYN[ID "S-PlanetarySectorReq" CH1]
N2020 M17
N2180 $WHILE 1
N2190 #WAIT SYN[ID "S-PlanetarySectorReq" CH1]
N2200 G01 XP1 Y-P2 F2000
N2210 LL channel_sync
N2220 X-P1
(-- divided orbit geometry --)
N0400 ...
N2410 #SIGNAL SYN[ID "S-PlanetarySectorOk" CH1]
N2420 $ENDWHILE