CNC Brain is ready! 6-axis Double Closed Loop Controller

[Dougal]

Hi Dougal.

I´m using G202 Gecko drivers with C1 Parallel Port Interface Card from cnc4pc.com. - Windows XP SP3 - Pentium IV 2,6Gh 1GB RAM - and it´s configured like mach3 recommend on his web. This configuration it´s working well with mach3 and smoothstepper.

BR
Antonio

Thank you.
Are you using mach3 as a sort of post-processor to generate code or are you inputting manually?
I'm still trying to decide which route to go software wise. I use solidworks and my mill is not yet operational.

[brccrb]

There are three problems fixed with the V1.6.4 software/firmware release:

1) In some systems, the autotuner doesn't detect the "wobble" correctly and as such doesn't tune the algorithm to compensate.
2) There was a combination in the configuration that could cause the machine to slow down unexpectedly. This was fixed on most systems with V1.6.3.
3) Interpolations on linked axis (where two axis act as one) would unlink the axis on circular interpolations.

**As for when V1.6.4 is released, I don't want to put a date on it, but it is very close. We are running very behind and playing catchup (No denying that fact)

V1.6.4 got caught between major enhancements, bug fixes, and bad timing. Made the update WAY too big.

Don't plan on making that mistake again (hindsight being what it is ). We prefer small, quick changes.


s/Bruce

[Switcher]

I did a little testing, for a custom cncbrain screen.

I replaced the "Run" & "E-Stop" buttons.

I used Inkscape 0.46 to create the .png images, & tweaked the button settings in VB.net 2005.


.

[dirtdiggler]

Cool switcher!

Off the subject, does anyone know if a VFD needs to have any type of extra protection like opto isolation, or can I run the Brain direct to the VFD to control it?

[granado]

Thank you.
Are you using mach3 as a sort of post-processor to generate code or are you inputting manually?
I'm still trying to decide which route to go software wise. I use solidworks and my mill is not yet operational.

Hi Dougal.

I don´t know if I can help you because I only use my plotter for raster images and the typical polygonal 3d files.

To generate the gcode I prefer to use software, by hand only very simple works but it´s very tedious.

For raster images (relieves) I can tell you that you can get the same result with mach3 as in an expensive program. For poligonal 3d files if you don´t want to spend money I suggest this Gmax+CNCtoolkit.

But usually I don´t work with solid models like generates solidworks. I suggest you to get the one that you understand how it works easily .You will get the same results with a lot of programs. Only big companies needs the latest strategies for milling. For my work it´s the same that my machine spent 4:30 hour or 4 hour . But if you have money my favorites are Delcam products but a lot of people prefer 1ºMastercam, 2º BobCad-cam , 3ºOnecnc...


BR.
Antonio

pd:sorry for my english

[LUCKY13]

Cool switcher!

Off the subject, does anyone know if a VFD needs to have any type of extra protection like opto isolation, or can I run the Brain direct to the VFD to control it?

There doesn't appear to be enough info around to really anwser that question. The Brain manual has a Spindle section in it but the section thats listed are not in print (the listing is there but the info is not).


A lot might come down to what type setup you would be running. I have never used a VFD to know what you have ot have to run it. If there is relays involved I would look into using opto,s if the Brain is used to trigger them. There is no info that I have seen that says you need to do this but I would if I was using relays. If there is a sensor involved it depends on what voltage it uses IMHO. If its a 5v sensor I think it would be OK to use without opto's, all though the manual shows to use opto's with a sensor. Anything above a 5v sensor I would use a opto with it. NOw the power suply that feeds this sensor might have something to do with it. If the sensor (for RPM or possition) that connects to the Brain has a power supply that could short out and feed it more voltage then a opto would be a good safty to have. But if you used the same power supply that feeds the Brain it should be OK. In fact that is the way I would use a sensor in this system, feed it with the same 5v that feeds the Brain that way you want have any high voltage problems and you would not have to have a opto that may effect the sensor signal ability to send signals at high speeds.


To use a VFD I think you need a 0v to 10v signal if I understand right. You might need a DAC board to do this because I believe the brain can send a PWM signal, or a step & dirrection signal, but not a 0v to 10v signal. WIth the DAC card it can do 0v to 10v (plus a few other combonations). So in that case you would not need optos because you really cant hook straight up to the Brain on that part anyway.



Now I am still learning about the Brain and all this electrical stuff so it would be best to get anwsers from others and verify this info. Don't take my word for it in other words. But as I understand it this would make sense to me. Any relays used no matter what voltages are involved I would use optos because there is to much chance of crazy voltages reaching the Brain.


Jess

[dirtdiggler]

Thanks for the info Jess.

My system is fairly straight forward. I have the VFD connected directly to my spindle and can control it manually on the VFD if needed. My hi lo shives are controlled separately with solenoid. My VFD takes digital and analog inputs but I'm not sure if it can take PWM or not. I know the CNC Brain has connections to control a VFD so it seems strange that I would have to get an additional DAC board to control it. I know Mach 3 can control a VFD with a simple breakout board.

Anyone else out there have their VFD setup with a Brain???

[Switcher]

Just thought I would let everyone know, that Paul (CncAdmin) made a new forum for CncBrain.

This single thread is getting very long.

Here is the link to start new CncBrain threads.

http://www.cnczone.com/forums/cncbrain/


.

[Larken]

Does the brain buffer commands ? Does it have ram to store the Gcode as it runs it?

How big is the buffer, or does it just run 1 line at a time from the PC.

[turmite]

Hi Larken,

If you mean can you load a program and unhook the computer the answer is no. I don't know if it is drip feed or block, but I do know the pc has to remain attached. One thing that is different though, is you can run as many brains and programs as your pc has capacity to handle, all doing different jobs on different machines and or different kinds of machines.

Bruce is supposed to have the latest upgrade to the software this weekend, but will just have to wait and see. I have decided to wait no longer to get the low cost linear scales that are coming, but to begin to collect and assemble some of the timing belt tractor encoders in addition to motor mounted encoders. As soon as I get the parts together....that equals $$$, I will start the process, and keep a diary as well as photos and maybe a little video.

Mike

[dirtdiggler]

Turmite,

Where did you get the low cost scales and tractor belt encoders? I'm curious to know what your setup is going to be like.

I'm still on the fence about purchasing a CNC Brain for my big old Series II Boss9. The thing I do like about the Brain is that it has all the I/O's built in for a simplified setup. I also like the included software interface.

I would have to purchase a breakout board, I/O board and smooth stepper to get similar fexibility, and also purchase Mach3. On the other hand there is so much support for Mach3 right now.

If someone gets it to work successfully on their mill then it would be an easy decision but so far I haven't heard from anyone who's got one moving without some buggers. Hopefully the next update will fix the problems and we can see some examples.

[turmite]

Turmite,

Where did you get the low cost scales and tractor belt encoders? I'm curious to know what your setup is going to be like.

I'm still on the fence about purchasing a CNC Brain for my big old Series II Boss9. The thing I do like about the Brain is that it has all the I/O's built in for a simplified setup. I also like the included software interface.

I would have to purchase a breakout board, I/O board and smooth stepper to get similar fexibility, and also purchase Mach3. On the other hand there is so much support for Mach3 right now.

If someone gets it to work successfully on their mill then it would be an easy decision but so far I haven't heard from anyone who's got one moving without some buggers. Hopefully the next update will fix the problems and we can see some examples.

Let's start with the easiest first. I don't have scales yet. The low cost string scale is something Bruce is working on and I can't give too much info, but proposed price would be around $70 for a long axis like my machine has, approximately 10ft to be close. The other long axis is 8 ft but would not require an encoder that long.

Second, the tractor encoder as I call it is posted further back in this thread somewhere.....I just can remember. It is made using a long length of timing belt glued to a flat surface with another timing belt making contact from the top using a series of pulleys to remove backlash. The center pulley has a shaft with an encoder (rotary) mounted to it. The accuracy of the belts being engaged with no stress on them is used to allow the rotary encoder's signal to be compared to the rotary encoder's signal on the motor. These two, allow you to have dual loop feed back.

Third, you do not have to have Mach 3! The software interface you said you like is all you need. Don't get me wrong, I like Mach, and it made a huge difference for me when I needed help or go out of business, but the time has come to make some changes again, and these changes dictate that I be able to use my cnc to it's fullest potential, and I can't do that with open loop! I will try to find the tractor pick and edit this post with a link!

Mike