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Re: THC antidive output turned off on 50 msec early before M

PostPosted: Tue Jun 20, 2017 3:53 pm
by shad
Yes Rob, you right.
Just I try to make life easier for my customers. Almost everyone is embarrassed that Sheetcam rules should be used :shock: . They want to put a plate and cut it :)
Also any time Sheetcam rules are not work correctly. It's sad.

Re: THC antidive output turned off on 50 msec early before M

PostPosted: Thu Jun 29, 2017 8:52 am
by shad
Hello Balazs!
Do you have any results?
Also I am notice if arc or circle consist from small parts (usually if dxf file generated in the CorelDraw) antidive future always activated, because UCCNC constantly accelerate/decelerate on every small part. If I am decrease Threshold value antidive not activated on this parts, but not activated on the corners and end of cut. I think we can not do anything.
It's sad :(

Re: THC antidive output turned off on 50 msec early before M

PostPosted: Thu Jun 29, 2017 9:08 am
by cncdrive
Hi Andrew,

We have no results yet unfortunately.
We started working on it already, figured out a way to overcome the issue but did not finish yet.
You know it is the middle of the summer and the collegues going to summer holidays, so somebody is always missing and so the others have to pick up more tasks, so now the development goes slower than it does usually. Anyways I will update you with news in this thread as soon as we will have results.

Re: THC antidive output turned off on 50 msec early before M

PostPosted: Thu Jun 29, 2017 9:18 am
by cncdrive
Also I am notice if arc or circle consist from small parts (usually if dxf file generated in the CorelDraw) antidive future always activated, because UCCNC constantly accelerate/decelerate on every small part. If I am decrease Threshold value antidive not activated on this parts, but not activated on the corners and end of cut. I think we can not do anything.
It's sad :(


Well, if the decceleration is because of the setup rules, defined by the acceleration parameter of the axes and the CV parameters then we can't do much about that, because it will be the physical limit of how the path can be followed, how the machine can accelerate and follow the different paths. And the anti dive function is a simple rule, it will always trigger when the feedrate drops below the set threshold level.
Unfortunately the limitation will be always the Physics on Earth, we can't override that. yet :D
Just a simple example is X=0 and G1 X10, G1 X0, with this code the axis simply changing direction, so it has to deccelerate and accelerate up again and so the anti dive function will trigger when the feedrate drops.
The only way to avoid this situation would be to have an infinate acceleration, and basicly that would be only possible if your motors have zero inertia and your machine axis has a zero mass. :)
Making the acceleration higher can help, but ofcourse you can't make it infinate high in reality.

Re: THC antidive output turned off on 50 msec early before M

PostPosted: Thu Jun 29, 2017 9:50 am
by shad
Yes, I am understand.
Now we start to develop our own rules handler.
Operator will open program file without any cutting rules via plugin, then the analysis of the trajectories will be done and the rules inserted in the right places.. Then this file will be load in the UCCNC.