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Author Topic: Mach3 Problems - Rant!!  (Read 37014 times)

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Offline Pinky

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Re: Mach3 Problems - Rant!!
« Reply #120 on: June 23, 2011, 03:05:28 PM »
Care to elaborate a bit more on that previous statement jrobson?

I assume it would give better feedback, but smooth stepper already fulfill that role?

But then again the Galil does have feedforward as well as a trajectory planner, so motion should be smoother and less jerky.

Heck I don't know anymore as who knows what Mach3 decides to do with all of the information at the end of the day.

Offline Hood

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Re: Mach3 Problems - Rant!!
« Reply #121 on: June 23, 2011, 03:09:35 PM »
I think he was meaning your max G's but could be wrong.
Hood
Re: Mach3 Problems - Rant!!
« Reply #122 on: June 23, 2011, 03:54:47 PM »
Yes it sounds pretty low, but I don't know Mach in a practical sense.

I had a quick look and this looks faster than 0.15G to me, running smoothsteppers and mach3... http://www.youtube.com/watch?v=uaG3pd8xuWw

Galil is quite pricey though isn't it?
Re: Mach3 Problems - Rant!!
« Reply #123 on: June 23, 2011, 04:01:58 PM »
Try this program see how fast you go before it starts to shake... put your machine in inch mode first.

Offline Pinky

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Re: Mach3 Problems - Rant!!
« Reply #124 on: June 24, 2011, 02:01:22 AM »
Logical thinking tells me the following :

G-code gets sent from Mach3 to the Servo's by means of pulses, the servo's then sends these pulses to the motors..... since the servo's currently have no S Curve or anything else fancy, the motors move according to the pulses received by the servo's which was sent by Mach3.

So in essence when you add a Motion Controller like Galil/Kflop , the g-code (pulses) gets sent from Mach3 to the Servo's, the servo's pass the information on to Galil/Kflop, which then adds in their "special magic" and pulses through the commands to the motors.

Since this is all a open loop system Mach3 doesn't really match up what it had sent originally and just excepts the fact that everything is 100% (which it is if everything is setup properly,or within your "tolerance" set in Galil/KFlop)

That all being said, this still doesn't add S Curve functionality anywhere as Galil/Kflop doesn't have that feature. I know Galil can handle the info for S Curve, but that needs to come from the Servo's.

AFAIK in order to get S Curve to work on my Servo's I need to make use of a PLC unit....... this is where it gets confusing for me hehe.

I'll do some more testing this weekend jrobson as I haven't had time for it just yet..... will keep you posted :)

This is just all theory, but sounds logical to me.

Offline Pinky

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Re: Mach3 Problems - Rant!!
« Reply #125 on: June 24, 2011, 02:22:19 AM »
Here's a nice little image from the KFlop website.

Offline Hood

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Re: Mach3 Problems - Rant!!
« Reply #126 on: June 24, 2011, 06:25:07 AM »
My understanding is not great but, as far as I know, with external controllers (well most) the planned trajectory is sent via a plugin rather than pulses being sent, so doing S-Curve would not be an easy task. What it would require, if that is the case, is the external device would receive the info of the planned trajectory, it would then need to break it down re-plan the trajectory then output the re-planned trajectory to the drives (step/dir or analogue).
Hood
« Last Edit: June 24, 2011, 06:28:25 AM by Hood »

Offline Pinky

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Re: Mach3 Problems - Rant!!
« Reply #127 on: June 24, 2011, 07:28:34 AM »
Yes it would appear I completely forgot about the "plugin" aspect of this scenario :(

So you basically end up with an "expensive motion control card" that's been stripped of most of it's functionality when run under Mach3.

Pretty much the same case w.r.t my Servo's drives.....they got excellent functionality, but useless under Mach3.

Back to the drawing board I guess.

Offline Hood

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Re: Mach3 Problems - Rant!!
« Reply #128 on: June 24, 2011, 07:38:16 AM »
Wouldnt say useless, would just say for the accelerations you are wanting with the hardware you have they are not ideal. Looks like you will need to get a controller that has S-Curve to fit to your router, not sure whats available but likely only the stuff from the normal people  or maybe some of the Chinese controllers that are on the market, certainly not talking $170 though, even the Chinese controllers are 10x that and I dont know what they are like or even if they can do S-Curve.
Hood