3.4.9

Hi guys!

I have gere a puma 200 robot arm from unimation.

All joints working
All brakes working
All encoders working
All ratios of the gears fit to encoder and measured angles anglea digital angle measurement tool.

After all this i change my kinematic to GENSERKINS

In joint mode all works.
In world mode i have issues.

There is one thing what make me headache... the TCP is upside down.

If i look to the puma560 vismach genserkins simulation.. its the same.

I set up the DH parameters.. i look to the puma 560 dh parameters in the simulation config and adapt them to my puma 200 parameters i get from the drawings.


In world mode Z looks ok... x y small radius?
But if i start the linux example i get errors of limits and kinematic errors.


Has someone the knowledge to look to it?

Thanks
Could someone help me please?

 

The is a minor thing that I hope is a simple fix.

The graphical display that follows the tool path is spot on with what the tool is doing. That's not a problem. What I noticed is the highlighted gcode shown isn't following the same position.
So if I tap a tool path line to highlight it in the grid of the graphic window it doesn't highlight that tool path in the gcode.
As you can see in the image I have the angled tool path highlighted which is supposed to be line 33, but in the gcode it's highlighting 29 which is the change in speed 5 lines prior.



A cursory search of the internet didn't reveal much other than recommendations to change g61,g64, but don't believe that has anything to do with this.

How do I correct this?

Thanks in advance.

I agree - for someone getting started, pay the $10 and get started.  I did that.  Just understand that you may outgrow the $10 option and need to get the $150 option (or in my case, the $220 option, and I'm looking at adding two more Mesa cards in the future).  The Mesa cards are in a completely different category of "cnc boards" and - if you need them - they're worth every penny, and cheap compared to the rest of the stuff you'll get.  But you don't need them to get started.
I think my only point is, if you already have a PC with a parallel port (rare these days), the $10 breakout is a better option than anything RPI-based, because it lets you get started with LinuxCNC, which has a better growth path than GRBL.  Assuming growth is a goal, of course

As for assembly challenges...  www.delorie.com/photos/cnc2/PXL_20231229_210308596.html (and it's gotten worse since then)

I will add one caution about putting a big capacitor on the output of a switching power supply - this may cause the supply to become unstable (depends on the supply) and may cause an overcurrent trip at startup (depending on the supply).  Most power supplies themselves have to solve this problem in their input stages, using current limiting devices.
 

Exactly! The PC (raspberry Pi or similar), power supplies and stepper (or servo drivers) can be basically the same. What I think is that the mesa card is not worth it, when you stay with open loop stepper motors and the mechanical system is not made for high speeds. But once you start using the I/O and Encoder inputs it is a real help to have a system that is easy to use, supported and works (happy customer of Mesa Plug n go kit).
For the picoCNC I paid roughly (guessing) 130-140€. Some things come with minimum quantities, others are discounted. It ends up at approx. 30€ a piece +-. I would have just bought the successor of it for 50$, but shipping would have doubled the price. To me it was more about the assembly challenge than the actual need for it. But there are "ready to go" options. 

 


One aspect is that a 10 mm carbide endmill will cost roughly the same. 



 

So for metal working the tooling and material quickly gets in regions where a Mesa card is really my least problem and I bought a 2nd Mesa card after the first one.

#no advertisement just random pictures. 
 

The OP implied he already had a PC to use, which you'd need for GRBL anyway (unless you added an LCD, buttons, and an sdcard), so adding a parallel breakout board is about $10, compared to the $4 for the pico and whatever the picocnc costs (assuming you can buy it, I couldn't find one for sale, but web site says "retired", but historically $29 assembled). You need the same stepper drivers either way.

A Mesa board is way more expensive, yes, but you get a lot more for your money.

there is an example:

./bin/rio-flow riocore/configs/TangNano9K/config.json

I'm using a Tang Nano 9k FPGA. How do I configure it to output a PWM signal to the spindle?

I am not sure if Linux CNC is really cheaper than GRBL. 
 

www.grbl.org/single-post/a-peek-at-the-picocnc  This is an example based on the Raspberry Pi Pico, all documented and possible to recreate "in the flesh". I bought the Pico boards for like 3€ a piece. The base board was more expensive, but not too crazy. 

• slow simple 3 axis machine without linear scales or rotary encoders probably works just fine with the GRBL
  • When I think of adding things "slaved axis", "linear scales", "automatic tool changer" I would go for LinuxCNC