Qvar Problem

[cncdrive]

Gerry, OK, if we take it into account that 3600 is larger than 360 then yes, to positive direction, but there is no position 3600 when there is a rollover, so it will basically never reach coordinate 3600.
Theoritically it could, but what if the user stops the motion then what will be the coordinate, then how would the control remember, that hey, I'm at coordinate 1800, because there was a movement from 360 to 3600, but wait I'm not there because there is no 1800 coordinate in a 0-360 range coordinate system.
So, this example code and condition would not move the axis also in mach3 for these reasons and I think this is how it should and has to work.

[Vmax549]

Balazs With G1 what ever direction you defined as positive it will move in that direction. With G0 it will move in the direction that offers the shortest path to the destination.

(;-) TP

[ger21]

So you are saying that with 360° rollover, you can't make any moves greater than 360°? And depending on current position, you'd potentially be even more restricted.

I always assumed that 360° rollover was just to simplify writing code. I wouldn't think that it should restrict movement.
But I've never used it, so I could be wrong.

Techincally, there is no 360° position either, as 360° = 0°. So stopping at 1800° would = 0°
I would expect that with moves greater than 360°, the DRO would reset at the end of the move. Although it really wouldn't be any difference it it just counted up and went to 0° each time around.
357°-358°-359°-0°-1°-.....

[Vmax549]

Sure you can move more than 360 deg. Teh machine will follow the Gcode exactly in G1 mode. The roll over is just a trick with teh DRO display. I have already done a 360 rollover with a macro loop LONG before 360 rollover was implemented.

Shortest rotation is a different dog and NOT to be confused with 360 rollover. UCCNC just does both as one function. Mach3 did it as 2 seperate functions.

(;-) TP

[cncdrive]

No, mach3 do it the same way.
Try it yourself and you will see.
Open Mach3, set it up for rotary A axis and set the rollover on 360°.
In MDI type G1 A0, then type G1 A3600.
No movement will happen, because coordinate 0 equals 3600 for Mach3 just like how it is for the UCCNC.

[dezsoe]

What happens (and what should happen) if I need two helicis in the opposite direction and write this code:

G0 X0 A0
G1 X100 A720
G1 X200 A360

[cncdrive]

Also it would make no sense that you program G1 A3600 in a g-code program and other out of range coordinates, because if you then stop the program then the controller would not know the "hidden" coordinate, because it has to be in the range of 0-360. Or even if the controller would remember that the user would not know, because the DRO shows 0-360 range only. So then again this makes no sense at all.

[Vmax549]

Dezoes it would move exactly like it is programed.
G0 X0 A0
G1 X100 A720
G1 X200 A360

First it would move as a coordinated move to X100 with teh A making 2 revolutions in teh positve direction then Make a move to X200 and A making a full turn back in teh negative direction.

Remember that 360 rollover is just a trick with teh DROs display it has NOTHING to do with how teh Gcode is inturpeted or implemented.

To add to the discussion teh Shortest Rotation function NEEDS to be able to be controlled as a Gcode to turn it ON /OFF because there ARE times you want it on and Times you want it off.

(;-) TP

[Vmax549]

Balazs what you are seeing in teh DRO has nothing to do with how that machine tracks where it is in 3d space or how it interputs teh Gcode. You can do a simple MacroLoop and have 360 rollover.

A dro value / 360 and teh Remainder will be the Curent A position in 360 degs display. It is just a trick with teh dro display. This has been around for a very long time now. It was created to help teh operator know where in a 360 deg circle teh tool was in relation to teh point of origin (A0) of teh rotary axis. It is just a visual trick nothing more.

AND as I said earlier this has nothing to do with the Shortest Rotation function. Completely different DOG.

(;-) TP

[Vmax549]

I would never base any function on how Mach3 did it. There are MANY things still broken in MACH3 or that were never created properly that will never be fixed.

Look at Fanuc or Haas or Fadal or Hurco or Mazak ISO, etc,etc as a reference.

(;-) TP