kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Reccomendations

Tue Jun 11, 2013 1:35 am

I think with that torque you'll need nema 23's.

The pololus are good for nema 17's and below. It can drive nema 23's but at lower torque, see here.

The driver I'm using is similar to this http://www.pololu.com/catalog/product/1182.
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

How much torque for cnc router about 2 ft by 2 ft

Tue Jun 11, 2013 2:19 am

How much torque and holding torque would I need just for. Milling wood PCB and plexiglass

Wire
Posts: 78
Joined: Tue Sep 11, 2012 6:46 pm

Re: LinuxCNC

Tue Jun 11, 2013 2:24 am

I think your expectations are a little high (well low) for 100 oz-in stepper motors. First the NEMA-14 frame size maxes out around ~40 oz-in just not enough space to get any more power than that out of it. Try looking for motors in the NEMA-23 frame size and bigger. If your looking for new off brand expect to pay $15-$20 each just for the motor. Sometimes you can find motors in that torque range cheaper on the used/surplus sites but they tend to disappear fast.

A better place to ask for recommendations / vendors of stepper motors would be over on CNCzone.
http://www.cnczone.com/

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

USB glitches

Tue Jun 11, 2013 7:12 am

There seems to be a problem with the usb system when running under xenomai. It seems that RPi drops some usb frames, I've initially noticed this issue when using the attached usb keyboard whenever linuxcnc is running. I thought the problem is with my keyboard, but the problem also happens when using a usb joypad as a simple pendant.

http://www.youtube.com/watch?v=BSF1F2dOui4

I have no idea how to address this issue; it's not a big problem but just a minor annoyance especially when you are trying to home the machine (before I've added the home switches). It doesn't affect the mdi and auto mode, unless if you use one of the buttons/keys as part of safety loop such as e-stop or run stop buttons.

Cheers!
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Removing excess

Wed Jun 12, 2013 12:20 am

Hi I am finishing up board probably be done by tomorrow night I am going to leave everything but inputs. Just to check myself I would just not connect those pins to that. Also would I just pull off U3 in order to remove outputs as I don't need them either.

Thanks and about how many holding oz-in are your steppers I think I will get the weak ones because I am only trying to mill small wood projects and pcb so I dont think I would need strong steppers.

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Removing excess

Wed Jun 12, 2013 1:01 am

Beutrocks wrote:Hi I am finishing up board probably be done by tomorrow night I am going to leave everything but inputs. Just to check myself I would just not connect those pins to that. Also would I just pull off U3 in order to remove outputs as I don't need them either.

Thanks and about how many holding oz-in are your steppers I think I will get the weak ones because I am only trying to mill small wood projects and pcb so I dont think I would need strong steppers.
Are you removing U2 as well? If you do, you'll need to power the pololus with 3.3v instead of 5v for the control side.

I have no idea how much torque my motors produce as I just picked them up from a local surplus store. I'm not really experienced on the hardware side of things, I'm more into software and electronics stuff.
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Circut boards done

Wed Jun 12, 2013 4:11 pm

Hello I finished I left out U3 inputs outputs and one decoupling capacitor. I am using a pi cobbler to split the pins up. I am ready to start programming but I still don't know what torque I need should be able to use nema 17 cheapies from that website and I will use polulus. What code would I need and how would I go about coding it.
Thanks
Attachments
breadboard.jpg
bad quality sorry
breadboard.jpg (53.98 KiB) Viewed 4524 times

Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Broken Link

Wed Jun 12, 2013 4:45 pm

Hey Kinsa I saw you uploaded something new to the pic programming page on picnc google. Well it says You are not authorized to access the webpage at https... and then try signing in. please reupload as I am getting close.

Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

More Broken Links

Wed Jun 12, 2013 9:24 pm

On the linux creation page for xenomai the downloadable minimal config dropbox link is down.

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Broken Link

Wed Jun 12, 2013 10:49 pm

Beutrocks wrote:Hey Kinsa I saw you uploaded something new to the pic programming page on picnc google. Well it says You are not authorized to access the webpage at https... and then try signing in. please reupload as I am getting close.
I don't know why that link failed.

It's updated now.
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Kinsa

Wed Jun 12, 2013 10:52 pm

Hey since your on do I just copy/paste everything from http://dl.dropboxusercontent.com/u/1702 ... xenomai%2B in order to configure.

Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Stuck cant figure out the config on the kernel

Wed Jun 12, 2013 11:07 pm

Can you explain to me what to do on ubuntu or linux to compile the kernel thanks.

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Stuck cant figure out the config on the kernel

Wed Jun 12, 2013 11:14 pm

Beutrocks wrote:Can you explain to me what to do on ubuntu or linux to compile the kernel thanks.
The instructions posted in the wiki should work fine on ubuntu.
Last edited by kinsa on Wed Jun 12, 2013 11:48 pm, edited 1 time in total.
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

The issue is

Wed Jun 12, 2013 11:33 pm

the link doesn't totally work for the premade minimum kernel so I am stuck

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: The issue is

Wed Jun 12, 2013 11:51 pm

Beutrocks wrote:the link doesn't totally work for the premade minimum kernel so I am stuck
Which link?
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

The wget

Thu Jun 13, 2013 12:25 am

wget http://dl.dropbox.com/u/17024524/linuxc ... xenomai%2B -O linux-rpi-3.2.27/build/.config
cd linux-rpi-3.2.27
make mrproper
make ARCH=arm O=build oldconfig

Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Its working

Thu Jun 13, 2013 12:31 am

but now what what do I do with that code I am assuming I just copy/paste it into the terminal but I tried that and it did not work.

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: The wget

Thu Jun 13, 2013 1:06 am

Beutrocks wrote:wget http://dl.dropbox.com/u/17024524/linuxc ... xenomai%2B -O linux-rpi-3.2.27/build/.config
cd linux-rpi-3.2.27
make mrproper
make ARCH=arm O=build oldconfig
Have you created the build directory?

What was the error message?
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Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Still more errors

Thu Jun 13, 2013 1:32 am

Have a look at this

Code: Select all

[email protected]:/home/aj/Desktop# cd rpi
[email protected]:/home/aj/Desktop/rpi# wget http://dl.dropbox.com/u/17024524/linuxcnc/config.rpi-3.2.27-xenomai%2B -O linux-rpi-3.2.27/build/.config
--2013-06-12 20:32:06--  http://dl.dropbox.com/u/17024524/linuxcnc/config.rpi-3.2.27-xenomai%2B
Resolving dl.dropbox.com (dl.dropbox.com)... 23.21.152.35
Connecting to dl.dropbox.com (dl.dropbox.com)|23.21.152.35|:80... connected.
HTTP request sent, awaiting response... 302 FOUND
Location: http://dl.dropboxusercontent.com/u/17024524/linuxcnc/config.rpi-3.2.27-xenomai%2B [following]
--2013-06-12 20:32:06--  http://dl.dropboxusercontent.com/u/17024524/linuxcnc/config.rpi-3.2.27-xenomai%2B
Resolving dl.dropboxusercontent.com (dl.dropboxusercontent.com)... 23.21.122.250
Connecting to dl.dropboxusercontent.com (dl.dropboxusercontent.com)|23.21.122.250|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 41148 (40K) [text/plain]
Saving to: ‘linux-rpi-3.2.27/build/.config’

100%[======================================>] 41,148      --.-K/s   in 0.06s   

2013-06-12 20:32:06 (669 KB/s) - ‘linux-rpi-3.2.27/build/.config’ saved [41148/41148]

[email protected]:/home/aj/Desktop/rpi# cd linux-rpi-3.2.27
[email protected]:/home/aj/Desktop/rpi/linux-rpi-3.2.27# make mrproper

[email protected]:/home/aj/Desktop/rpi/linux-rpi-3.2.27# make ARCH=arm O=build oldconfig
  HOSTCC  scripts/basic/fixdep
  HOSTCC  scripts/kconfig/conf.o
  HOSTCC  scripts/kconfig/zconf.tab.o
  HOSTLD  scripts/kconfig/conf
scripts/kconfig/conf --oldconfig Kconfig
#
# configuration written to .config
#
[email protected]:/home/aj/Desktop/rpi/linux-rpi-3.2.27# make ARCH=arm O=build CROSS_COMPILE=../../tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-
make[1]: ../../tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-gcc: Command not found
scripts/kconfig/conf --silentoldconfig Kconfig
make[1]: ../../tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-gcc: Command not found
  Using /home/aj/Desktop/rpi/linux-rpi-3.2.27 as source for kernel
  WRAP    arch/arm/include/generated/asm/auxvec.h
  WRAP    arch/arm/include/generated/asm/bitsperlong.h
  WRAP    arch/arm/include/generated/asm/cputime.h
  WRAP    arch/arm/include/generated/asm/emergency-restart.h
  WRAP    arch/arm/include/generated/asm/errno.h
  WRAP    arch/arm/include/generated/asm/ioctl.h
  WRAP    arch/arm/include/generated/asm/irq_regs.h
  WRAP    arch/arm/include/generated/asm/kdebug.h
  WRAP    arch/arm/include/generated/asm/local.h
  WRAP    arch/arm/include/generated/asm/local64.h
  WRAP    arch/arm/include/generated/asm/poll.h
  WRAP    arch/arm/include/generated/asm/sections.h
  WRAP    arch/arm/include/generated/asm/siginfo.h
  WRAP    arch/arm/include/generated/asm/sizes.h
  CHK     include/linux/version.h
  UPD     include/linux/version.h
  CHK     include/generated/utsrelease.h
  UPD     include/generated/utsrelease.h
  Generating include/generated/mach-types.h
  CC      kernel/bounds.s
/bin/sh: 1: ../../tools-master/arm-bcm2708/arm-bcm2708hardfp-linux-gnueabi/bin/arm-bcm2708hardfp-linux-gnueabi-gcc: not found
make[2]: *** [kernel/bounds.s] Error 127
make[1]: *** [prepare0] Error 2
make: *** [sub-make] Error 2

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Still more errors

Thu Jun 13, 2013 2:06 am

The error is about the missing cross compiler. Where did you save it?

You can specify the full path on CROSS_COMPILE variable
42

Beutrocks
Posts: 52
Joined: Mon Apr 22, 2013 4:00 am

Cross Compiler

Thu Jun 13, 2013 2:34 am

To my desktop how do I set the path

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: Cross Compiler

Thu Jun 13, 2013 3:14 am

Beutrocks wrote:To my desktop how do I set the path
Find where arm-bcm2708hardfp-linux-gnueabi-gcc is located.

Then set CROSS_COMPILE=<directory>/arm-bcm2708hardfp-linux-gnueabi-
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hybris
Posts: 52
Joined: Mon Jun 03, 2013 8:50 pm
Location: Tyrol / Austria

Re: LinuxCNC

Thu Jun 13, 2013 10:06 pm

hey there

@Beutrocks

maybe my monolog can help you :) http://www.raspberrypi.org/phpBB3/viewtopic.php?t=46039

Greets

hybris
Posts: 52
Joined: Mon Jun 03, 2013 8:50 pm
Location: Tyrol / Austria

Re: LinuxCNC

Sun Jun 30, 2013 6:43 pm

hey kinsa

Sorry for the dumb questions, i just want to know if i got it right:
With your image you send the position commands via the gpio pins to the pic nc (jr).
The pic on it translate the position commands to a digital signal for the pololu driver, which sends
the sequence for the stepper motors. Is that correct?

Thanks a lot! :)
Greets, Thomas

kinsa
Posts: 457
Joined: Sat Dec 01, 2012 10:16 pm

Re: LinuxCNC

Sun Jun 30, 2013 10:14 pm

hybris wrote:hey kinsa

Sorry for the dumb questions, i just want to know if i got it right:
With your image you send the position commands via the gpio pins to the pic nc (jr).
The pic on it translate the position commands to a digital signal for the pololu driver, which sends
the sequence for the stepper motors. Is that correct?

Thanks a lot! :)
Greets, Thomas
Hello Thomas,

Yup, that's how it works.

LCNC converts the gcodes into position commands which are transmitted thru the GPIO pins using SPI. The pic32 then converts these to step/dir signals that the pololus understand.

Cheers!
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