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Some pictures of your machine would help. tommylight and I have both built hot wire foam machines.
Personally I would use ladder logic for the pause control. I am confused however as
to why your wire breaks often enough that you need a system to pause the program when it happens.
Some questions.-
What type of wire are you using Titanium? NiChrome?
How much tension is the wire kept under?
What gauge is the wire?
How hot are you running the wire?
What voltage is the wire powered with?
What frequency is your PWM signal?

 And in other dumification news we have this . I am sure a Nigerian prince is ready to export all over the world
for a small transaction fee that will be reimbursed once you receive the vehicle.
enjoy
 

Should I just download the bim from pyodc and put it in stlink v2 and after that I will be able to record remora on nven? Could you detail me step by step?

I guess we could simply calculate the length of our 3D residual vector and pass that back as the error value to be minimized.

Very nice this will be perfect for base thread.
The pin header that has the board can drive 4 close-loop steppers ?


(i have a rockpro64 any hope for this for an image with preempt-rt kernel?)

yes, eq 14 :
 

because we set s1=s2=s3=s4 we need to integrate from 0 to 4*s1.

It's still unclear to me how dogleg optimizes a system of 3 equations as it would not get back a single residual value but rather a vector with 3 residual elements.
 

@Arciera,

Thanks for your responce.

Indeed, the error is likely the endpos. I was thinking the same yesterday night.

error = distance "requested endpos" - "guess endpos"

When playing with different Y11, 21 gues values using the same length s1:
Changing the guess values Y11, Y21 will influence the rigid of the clothoid compound.

Picture values from left to right :      
Y11=1 Y21=1
Y11=0.5 Y21=0.5
Y11=0.1 Y21=0.1
 

Now i will try to setup the dogleg method. Using our new criteria.

The Jacobian usage seems to be more effiecient in finding the solution. But without is also no problem and
will result in more iterations to find the fit solution.

Your point at eq44 if solved here as a example : eq14
This eq14 is not a optimized function yet.  And for calculating the clothoid endpoint, i want to make a
few one liners today.

Plan :
1. Create a function to calculate the spline endpoint efficient, using y11, y21, s1.  Eq14 current code is not effiecient for this.
2. Create a Dogleg fit function to optimize y11, y21, s1 values that the spline compound fit's the given endpoint. (Magic function).

For info, to be aware off:
In linuxcnc we use G2,G3 as helix. This abstact isn't taking account of helixes. Only flat arc's for input,
We will create a solution that uses a end vector of any type of curve.

For info:
Deepseek is better in reading pdf files than Chatgpt.
Also the code example from Deepseek are better.
So i often just upload the clothoid_3d.pdf to deekseek and start asking questions.
This really helps the process. Deepseek just throw's out a full dogleg c implementation. It's amazing.

Let's hope the Magic Function will find the solution for endpos.

Using any Mesa hardware means you don't need a base thread, you only need a servo thread. The latency/jitter figures are far more relaxed with Mesa hardware.
Just some examples of what kind of hardware is ok with Mesa.

If you are happy with the 2 Port system and don't want to rewire everything, a 7i92T with the right firmware is just a matter of unplugging the cables from the breakout board from the LPT ports and plugging the cables into the 7i92T. 7i92T is some what cheaper and can be later upgraded with a 7i76 card.

J3355B-ITX (replaced by the H2 Plus due to space constraints)
Dual-Core Processor J3355 (up to 2.5 GHz)

Odroid H2 Plus (my current choice)
Intel Quad-core processor J4115 (14nm) with 4MiB Cache, up to 2.5Ghz(Single Thread) or 2.3Ghz(Multi Thread)

Lenovo M72E (found this one on the side of the road on a council cleanup)
With i5 3470
Quad core

All work fine with Mesa Etherent cards.

RPi5 works fine with Mesa Ethernet cards and SPI cards. 7c80, 7c81

The above Lenovo and J3355B work fine with Mesa cards that work with EPP interface. 7i90

Honestly I haven't heard of any issues with Debian Bookworm and Mesa cards, where the issue can raise it's head is with some realtek cards, but this is far easier to fix that any latency issues.

Samba is quite easy to setup, these is a plugin that MX Linux has that allows right clicking on a folder and sharing it via samba. No messing around with editing files. The only thing that is required is create a samba user that you then use to connect the share with on the windows Box.

To show the difference that not having a base script.You'll see quite a difference in the figures.

could you post the exact error message?

scotta wrote:

Thanks for sharing. I did investigate reading the device tree when working on the RP1 driver but took the easy path so as to focus on the DesignWare SPI side of things. Looks like I'll need to rework the board detection. At least the Mesa code will be a great starting point.
 

You actually did an amazing job on the DesignWare SPI and I can't thank you enough for it!

Looking at the readme in the dogleg library:
github.com/dkogan/libdogleg?tab=readme-ov-file

It seems that we might want to start with 'dogleg_optimize_dense' or 'dogleg_optimize_dense2' as these calls don't expect a Jacobian.

 

'p' would be a vector with 3 elements [gamma_1,1, gamma_2,1, s_1] containing our initial guesses when calling and the optimized results in the end.

'Nstate' = 3

'f' would be the system of 3 equations in the last post. This is where I'm stuck at the moment.