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its fixed now, it was some small potentiometer on the drive that was set to set wrong position and after that it runs super smooth

Hi all, 


I apologize for the delay. I have been busy with this and another project. 

So the new rackrobo does have a way of modulating power output.  I was able to get my hands on a power supply at no cost to me. They are having some issues but it seems like the probability of an issue occurring is still pretty small.  If I do have issues I'll look at swapping the power supply. 

Yes I imagine sinker would draw a lot more power then wire and especially hole drilling. 


As far as linuxCNC control of EDM. Does anyone know if the ones like tommy was showing are using reverse feed rate and short detection?  It seems like it wouldn't be too difficult to pause the program when a short is detected, but does anyone know if it is possible to get reverse feed to pull out of the short and then reengage? I know this is how professional machines operate and I would think someone has figured out how to do this with LinuxCNC...  Any LinuxCNC wizards out there know how to do this?


Best,
-Dylan

Hi,

Years ago i had the same problem as you. Was cutting a Thermal Dynamics 200 Amps + compressor + cnc.
I managed to get a diesel power pack on a trailer.

So if you are like a professor you could manage to create a big iron flywheel in your workshop.
Driven direct drive by a electromotor.

Say the flywheel mass is about 2000kg, rotating at 500 rpm. This will solve power dips for the whole street.
It's a silent & cheap solution.







 

Hi,

So far i am happy with the insights tonight.

Source code:
rtapi_function_loader

Above is a repository testing the posix pthread, running different .so libary functions named "test();".
It's more or less how the original rtapi workflow is.

This is tested ok with a base thread nano second : 25.000
And you can set the used cpu's. You can set it by  passing a cpu_list = {0, 1};

If you load 4 instances of the rtapi_function_loader class and assign each
instance to a different CPU (CPU 1, CPU 2, etc.),
each instance will run on its own dedicated CPU core,
ensuring that all 4 threads run in parallel without sharing CPU time.

We have also a priority for the rtapi_function_loader's pthread in the value 0 up to 100.

Ok, now next thing is maybe to look when, where and why we need to allocate shared memory blocks.

wiring for the sanyo drives. i forget now if the toshiba are different.  you really do need it all connected including voltage references, start(enable), etc.
 

alexbrem89 wrote:

Does anyone happen to know how I can connect the spindle orientation?
I have the spindle turning, but not yet the orientation
 

I never got that far with mine. I dont think its covered in this thread, but i think some others did it elsewhere. I think most people switch the spindle to A axis, and then home. 

These are ac servos. noise should not be of any issue as it a differential analogue signal.

I think its just connected wrong.

Does anyone happen to know how I can connect the spindle orientation?
I have the spindle turning, but not yet the orientation

Philip wrote:

i tried with a battery and and variable psu but it makes alot of noise and shuts off because of overheating after maybe a minute of running, i guess the drive is overheating since i dont got the tempreature sensor connected.

Noise and vibrations are from interference with unshielde/ungrounded wires, but since it is an old machine, check if motors have brushes and if they do, yank them out and use compressed air inside the brush orifice to remove the fine dust that gathers there and can cause heating during normal work.
Do keep track at what brush was in what orifice and how it was oriented, that is very important.

That looks much better.

You can monitor the maximum times in when LinuxCNC is running with:

halcmd show param *.tmax

(these times will be in ns on non-x86 platforms like your Orange-Pi)

Thanks PCW for your reply, I remembered that I had compiled the Orange Pi 5 core and checked the network interrupts and they were different from the ones I had isolated before, so I changed the network IRQs to the isolated cores and now I get better results. I have done several tests and it has not failed again.

angel@orangepi5:~$ sudo chrt 99 ping -i .001 -q 10.10.10.10 -c 50000
PING 10.10.10.10 (10.10.10.10) 56(84) bytes of data.

--- 10.10.10.10 ping statistics ---
50000 packets transmitted, 50000 received, 0% packet loss, time 50002ms
rtt min/avg/max/mdev = 0.148/0.156/0.345/0.001 ms
angel@orangepi5:~$ sudo chrt 99 ping -i .001 -q 10.10.10.10 -c 50000
PING 10.10.10.10 (10.10.10.10) 56(84) bytes of data.

--- 10.10.10.10 ping statistics ---
50000 packets transmitted, 50000 received, 0% packet loss, time 50001ms
rtt min/avg/max/mdev = 0.155/0.156/0.186/0.000 ms
angel@orangepi5:~$ sudo chrt 99 ping -i .001 -q 10.10.10.10 -c 50000
PING 10.10.10.10 (10.10.10.10) 56(84) bytes of data.

--- 10.10.10.10 ping statistics ---
50000 packets transmitted, 50000 received, 0% packet loss, time 50001ms
rtt min/avg/max/mdev = 0.155/0.156/0.186/0.000 ms

@Arciera,

Thanks for the links !

As @rene-dev mentioned to me it is currently not possible to run tests in parallel, mainly because there can only be one linuxcnc instance running at a time.
It seems not so easy for me to create hal instances in a short time period. Segment fault.... Huh.
Then i looked more in detail to the rtapi code.

I came to the conclusion that linux cnc hal at runtime is clamped to a single cpu core.
If user installs a preempt rt kernel, we can use posix.

This posix is then is used by rtapi to run's a pthread very fast and quite time stable.

So what looks like a insmod command in rtapi, is not a insmod command at all. Insmod in this case is not a kernel insertion command.
Insmod in rtapi is loading a .so lib.

Rtapi can be seen as a library function loader. And does a little more.

For run(); read rtapi_app_main();

So if you have a lib called test.so. This lib has a function run();
Then the Rtapi opens the "test.so" lib and finds the function "run".
The lib stay's open and rtapi creates a pointer to the function run();.
This pointer is used later on to execute the run(); function.

The rtapi then finally has a list of loaded .so libs  with their names and their run(); functions (or pointers * to the run(); functions).
This final function list is then executed in order.
All the .so libs, have the same function name to execute.

This is basicly what rtapi does.

The hal environement is coded in c. But can eventually be coded in c++. Because rtapi is also written in c++. And there is no
real .ko hocus pocus.

Transforming hal into a multi instance hal environment is quite a lot of work i have seen so far. It also comes with some
difficulties to solve.

In the end of this post :
Will take some time to create a rtapi look alike example.

Creating a test app that load's .so libs with a certain function. Then run the function list.

But then with examples how to choose the cpu's.
How to set priority flags to .so libs wich are time critical.
How to create parallel or detached processing using posix.