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@Arciera,

Thanks for responce.

3. I think that's the same behavior as the current planner
Yes, looks like so.

@Julian,

Also thanks for responce.

I like the idea also. So you want to go nearer to the points before doing a spline.
The idea is polyline simplyfication. Then i thought maybe use :

Douglas-Peucker

 

Visvalingam-Whyatt

 

However both algo's don't satisfy cnc path smoothing.

Then i tried something on a paper with a pen myself. And came up with the triangles
centroid idea.

In Cgal they use the idea off convex hull for triangles.

 

However,
this idea is not really using a convex hull method, it's more like a forward sweep convex hull or
triangle-fan.

When the resulting line strip looks ok. Then doing a splinify is problably most succesfully.
However, if you use the "filter algo from previous post" then used as the planners back-end,
the result is maybe good enhough, you don't need the splinify.

Splitting in half between edgepoint and last point if next angle is the ame direction. And going one step back if the direction will change (not perfectly described of course).
I don't get it. .  But does'nt matter. Thanks for your help yesterday !


From DeepSeek:
Possible Names or Related Algorithms:

Laplacian Smoothing:
A common technique in mesh and curve smoothing that averages points with their neighbors. Your method is somewhat similar but uses centroids and halfway points instead of direct averaging.
 

Centroidal Voronoi Tessellation (CVT)
While not a direct match, CVT involves optimizing point positions (like centroids) to achieve smoothness in a geometric structure.


It looks like the algo is similar to Laplacian smoothing for the first stage. liqimai.github.io/blog/AAAI-18/
However the Laplacian is not using centrold's. And here it show's only the 2d solution. And algo is
working different as we use it.
Then it has no second stage.

 

That is quite normal, Linuxcnc implements it's own kernel driver to talk to the parallel port.
It doesn't matter what you believe, what matters is what the chip data sheets say. This is where you will get your proper knowledge. If this feature has not been implemented in the silicon die no amount of wishing nor debating will change that. As the docs say not all parallel ports implement the open collector feature.
What you need to do is determined the actual chip used on the parallel port card, find the chip's data sheet and carefully read through the document. If there is no mention of open collector outputs, that feature does that exist.
If it is mentioned you will have to determine if it is turned on via writing to any documented registers or whether there is a pin or pins on the chip that turns that feature by tieing high or low. If that is the case you will need to look at the board and see if the manufacturer has bought these pins out to a pad or not.
YOU NEEED TO READ THE DATA SHEET OF THE CHIP. This the only way to know for sure.


And hopefully the chip is the genuine item and not a clone.

testing servo motor... with 30000 is good acceleration
but i feel that can go 3 times faster mechanically (has low inertia).
I have got a 7i48 if drive it with analog -10+10V can go faster ?
How much FF2 & I needs for 60000 ?

What is better in general for driving servo that supports step-dir analog speed and analog torque ?

Hi,

Today i thought maybe add a path filter to the planner. This is also just an idea that came up.

It uses no G64 P[x] value.
It uses no path blending and or fillets etc.
It works as backend filter for any path using G64 P[x] values.

It uses a hal_path_filter input parameter between 0 and 3000. Imagine 0 up to 3000 servo-cycles.

This is a simple algoritme that calculates the avarage of toolpath points [bufsize] in real time.

The runtime property is that how lower the speed, how closer it gets to the path. Deviation is small.
How faster the speed, deviation becomes bigger.
If normally the motion stops every gcode line because no G64 P[x] value is given, this algo keeps
up velocity's. In fact it automaticly generates endvelocity's for the trajectory.

In halscope the joint.x velocity and acceleration values, are nice.

hal_path_filter = 500
   

hal_path_filter = 1000
 

hal_path_filter = 2000
 

hal_path_filter = 3000


Show multiple filter values, 500, 750, 1000.
 

Let me know what you think?

 

self.execute("M64 P0")  ?

    Have a look here. With lspci -v i see no kernel drivers.
i beleive this could be the problem.
how to install the drivers? Since the parallel port supports different modes according to the manufacturer, im quite sure it is possible to acheive 9 inputs with proper knowledge

Nice job guys....
 

rodw wrote:

Try a Meanwelll MDR-10-5 (2 amp)
 
 

Hi Rod,

Thank you for the suggestion. I like to use the Meanwell MDR-10-5: au.rs-online.com/web/p/din-rail-power-supplies/7127402

It does not include the DIN Rail, which RS Online Supports say is: DIN Rail: au.rs-online.com/web/p/din-rails/6485722?gb=s

I would like to use the terminal blocks as per your spaceship video:





I sent them these two images stating that I would like to use them with the above power supply and DIN Rail.

But supports said not enough info, and suggested this: au.rs-online.com/web/c/connectors/termin...ds=Phoenix%20Contact

I also inquired about the earth one ( yellow and green ), but supports did not give a link for that.

Would you happen to have any suggestion on this terminal blocks, please?

I will use this power supply only for the Mesa 7i96s, so many of this terminal blocks I should need, please?

( For the stepper motors, I understand that I will have to have a separate power supply. )

How to build a spaceship with a Mesa 7i76e ethernet card - a tutorial for new Linuxcnc users

https://www.youtube.com/watch?v=75tAJ4tdBgs

Than you Rod.

I'm trying to add spindle enable and spindle out to my configuration (7i95T + 7i78), but heaving some difficulties to set it up in mesa CT as it is all greyed out under spindle tab and also under 7i78 outputs. Only under 7i95T outputs are 6 of them available.
I would like to use spindle outputs from 7i78.

Hi guys,
I've been lucky enough to find a used EL4031 used at an affordable price. I have set it up on LCNC and I can enable it. I can't keep going one with the setup because I'm a bit lost on what I should do next. I have found this example:



I'm not asking to do it for me, I want to learn so a practical example should be enough, I know the basics of C+ and did many arduino projects but I'm a bit lost on how to write code for LCNC.

Those pins need to be open collector pins according to the docs.
As you have followed the correct procedure to test if the pins are open collector and you saw no change that indicates that those pins are not open collector and can not be used as inputs.
As far as I know, I haven't looked at any data sheets, there is no way this can be changed.
I'm guessing this is the way the hardware is implemented on the chip itself, IE at the silicon die level.
The only way to find if this can be changed is to read the data sheets of the chip used on the board. Even if it may be possible it may require some mods at the PCB level.
Bear in mind that as I have not read the data sheets most of the above is speculation.

Hello all,

i have the following PCIe Parallel port card from StarTech , with Asix - AX99100 chipset which offers me 5 input and 12 output pins on default settings.
i tried to configure it on x mode with loadrt hal_parport cfg="d010 x" in my hal file. But i do not get the pins 1,14,16,17 to work as inputs. (they remain high and do not change states. I tried using a 470 ohm resistor between the pins and ground but the state does not change.

The manufacturer states that the port can be configured as SPP,ECP and EPP and is based on IEEE 1284 standard. 

Please help me to change the parallel port data transfer mode to the one which supports 9 inputs.

i have tried dmesg | grep parport in the terminal but there is no information relating to parport. and there is no way to change the mode of my parport from bios because its a pcie plug and play card.

there should be a way to change modes but i do not know where and how.

any help is much appreciated!