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Re: Constant velocity
« Reply #10 on: September 04, 2007, 08:09:25 PM »
Brian,

Was the CV problem fixed in ver. 2.45 released today or will it be fixed in the next version?
Also some sort of tutorial or manual on what all the CV settings do and a how to go about setting them would be great.

Thanks
George
Re: Constant velocity
« Reply #11 on: September 05, 2007, 07:26:29 PM »
The update is on the web now :)

This setting will tell Mach3 to come to a full stop if the angle from one intersection to the other is less then X amount. For example if you have a move that makes a 120 move you will not stop and the CV will fly right through it.. this will round the corner but you will not care because you don't need to have a sharp corner...

Now in the next example the intersection is 10 Deg (Looks like a sharp point). To make this a sharp point we need to come to a full stop at the intersection...
Hope that helps
Brian
Fixing problems one post at a time ;)

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Re: Constant velocity
« Reply #12 on: September 05, 2007, 08:12:34 PM »
What is the CV feedrate setting for?

Thanks
George
Re: Constant velocity
« Reply #13 on: September 11, 2007, 09:53:31 PM »
This will make the Blending of the moves happen at Blend feedrate... But the problem is that on some tables this will make the movements seem jerky when this is added... But it will make it so that you have smaller rounding in the corners.

Thanks
Brian
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Offline stirling

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Re: Constant velocity
« Reply #14 on: September 27, 2007, 05:44:20 AM »
I upgraded R2.45 post sep 5th but have not had chance to really try it out until today and I'm sorry guys but I still can't make any sense of the CV tuning settings. If anything they just seem to have gotten worse and more confusing.

This setting will tell Mach3 to come to a full stop if the angle from one intersection to the other is less then X amount.

The only settings now appear to be CVDistance and CVFeedrate - I can find no setting relating to any angle.

What is the CV feedrate setting for?

This will make the Blending of the moves happen at Blend feedrate...

This doesn't seem to be the case (on my system at least)

I've tried to figure out the logic of CVDistance and CVFeedrate for myself but thus far I can't make any sense of either of them.

CVDistance seems to tighten the blend arc the smaller you set it but it doesn't appear to have any correlation to any real distance. This is on every intersection regardless of angle.

CVFeedrate seems to be a + or - to the current feedrate but the only effect it seems to have is either no effect or it effectively turns CV off completely. Again I can't see any correlation between different values and any effect. Certainly whatever it's set to the actual feedrate doesn't seem to change.

Has anyone - particularly those who've contributed to this thread had any better success? or is it just me?
Re: Constant velocity
« Reply #15 on: September 27, 2007, 08:22:24 AM »
Go to Config/ General Config and there are CV settings there...
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Offline stirling

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Re: Constant velocity
« Reply #16 on: September 27, 2007, 09:49:28 AM »
Thanks Brian

I'm afraid I'm still having trouble getting things to work as I'd like - would you walk me through a couple of things please?

As I understand it there are the following settings with regard to CV tuning (ignoring things like plasma cutting etc.)

On the Config/General config dialog: two items:

 a)  CV Dist Tolerance (units)
 b)  Stop CV on angles > (degrees)

On the Settings screen: two items:

  c) CV Distance
  d) CV Feedrate

a) and c) seem to be the same thing i.e. when you change one it automatically reflects this in the other.

Concentrating for the moment just on "Stop CV on angles >". Let's set it to 90°.

Please see the attached two short gcode files. Both describe 5 pairs of lines describing different angles - approx 10°, 45°, 90° 135° and approx 170°.
 
The only difference between the two files is that cvtest1 starts at bottom left and cvtest2 starts at bottom right.

For the sake of discussion, if we now call the 90° quadrant between 12 oclock and 9 oclock quadrant 1, and the 90° quadrant between 12 oclock and 3 oclock quadrant two - we'll see that all blending for BOTH files ONLY occurs in quadrant 1. i.e. it seems that the "Stop CV on angles >" refers to the "global" 360° and takes no account of the angle at the actual line intersection. Surely this is wrong?

Offline Chaoticone

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Re: Constant velocity
« Reply #17 on: September 27, 2007, 10:10:10 AM »
Look at this thread, it tells you how to test different settings, the idea behind them, etc. etc.

http://www.artsoftcontrols.com/forum/index.php?topic=1724.msg10363#msg10363

I haven't messed with the CV settings much because my machine does fine with the defaults. If this doesn't clear things up for you, let me know. I will do some test and explain my findings the best I can.

I hope this helps,
Brett
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Re: Constant velocity
« Reply #18 on: September 27, 2007, 11:10:55 AM »
I will try to test... Could you make the file into 2 line moves and I can use that to test with... I can't have more then that to test with :(

Thanks
Brian
Fixing problems one post at a time ;)

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Offline stirling

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Re: Constant velocity
« Reply #19 on: September 27, 2007, 12:14:01 PM »
Hi Brian

Sorry - had a customer taking up my time all afternoon... ;D
Now back to the REAL work. I'm not sure what you mean by make the file into two line moves.

Hi Brett

Thanks - I've read Arts post but I think my question with Brian at the moment is that CV may be meant to work like that, but I don't think it actually does. I'm sure Brian will correct me though if I'm wrong ;)

Ian