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My layout (no cabinet yet) is very messy, but here's an old photo of it:
www.delorie.com/photos/cnc2/PXL_20240324_210728573.html
I went with DIN rails for mine, one for mains power control (top) and one for low voltage (middle).  The mains rail has circuit breakers and contactors, and the contactors are wired into the estop chain.  The main logic power's contactor is wired into the on/off buttons so it defaults to off after a power failure.
You can mount power supplies on their sides if you need to save space.
Don't forget to leave space inside the box for vents and fans top and bottom.
Your estop should be more conveniently located.  Or buy more than one of them

Thank you Andy.
I did get the .tcl version running, but it is tied to Axis so the Reload button doesn't appear for PathPilot.
I will give the python one a try, at least there is then a hope of tying it PathPilot somehow.

Hi Juergen,

Thank you for your purchase and the kind word.

Step, STL and DXF work. DXF will be prompted for an extrusion thickness.

Hope you like the experience.

I treated myself to these
Very easy installation super....
A basic question which drawing expot should I take from Freecad ???

King regarde
Juergen

Got it, moving eventually to uspace is the right move...

I'm still here, but not quite as often as I used to be, I had to switch jobs and no longer have as much time at a computer and don't work with CNC routers daily any more. I can and will offer what advice I have for free here. So ask questions.

I live in NE Ohio. So unless you are local to me I will not be able to offer on site consulting/work. I simply do not have the free time between family and work commitments to do a lot of travel.

I apologize I didn’t get to this last evening, I’m off the next few days after today and I’ll have a gander.

What version did you roll back to?

I should have asked before, can you share your cut file as well?

i just thought about this, a interface without the load of the display manager, searched i came to your project. I have a rpi4, a 7i90 and a 7i84, a 26pin conector and a sort 50pin cable. 7i90 flashed to spi. every thing to test it. i reply with my feedback, great project.

Hallo,

the linuxcnc-ethercat version is : linuxcnc-ethercat (1.42.2-1)

Gruß
Rüdiger

Depends how you define "basic". My paid-for Fusion costs me something like $400 a year and that includes indexed / wrapped 4th axis which allows me to do things like splines and gears. True simultaneous 4th axis requires the ruinously expensive manufacturing extension. That's always been a disappointment that rather limits the use of my 4th axis.

Exactly our point. For the same cost as a one year Fusion subscription of their basic CAD and CAM, you get Takshak for life which has an even larger rotary operations library than Fusion. If you buy it before 30th September, you get it at half that cost.

Anyone saying 200 USD is too expensive for that capability sounds rich enough to pay 1500 USD per year to Fusion and I have no beef with them. 

No you got us wrong. The license has a launch offer of 199 USD. That offer is for 30 days from launch and ends on 30th September.

Post that the launch offer ceases and anyone buying from 1st October onwards pays 399 USD.

If you bought it before 30th September, its your forever at 199.

Irrespective of whether you bought it for 199 before the offer expires or 399 after it expires, you still get 30 days of usage to decide if you want to keep it. If you dont like it, you can ask for a refund.

You can add multiple rules, use the right click rules dialog and add as you need, you can also add multiple channels to use in the expression. The expression can have multiple else continuation for each test to display.  There are examples in the ui, take a look at some of the labels and there rules.

Lcvette wrote:

Then you should not need any python code use just rules
 

This is what you meant when you mentioned the if/then/else rule statement earlier, right?  That gets me the three color states for the stopped/running/paused indicator.

To get the three text values, I'd need a second if/then/else rule for the widget... or the same status channel rule can do both appearance and text displayed?

A follow-up on **FabScan**, the LinuxCNC camera tracing/digitizing project I posted about earlier.

FabScan has now reached:

**v0.6.0-alpha.1**

Project:
github.com/FabLabRacing/FabScan

I am definitely not calling it finished, but I think it has crossed an important enough milestone to call it an alpha and, more importantly, to start asking the open-source community for help improving it.

## What Changed

The biggest change since my original post is the tracing architecture.

The earlier versions were basically:

detect local line
→ calculate correction
→ move
→ repeat

That worked surprisingly well on simple geometry, but corners eventually exposed the limits of that approach. I spent quite a while developing various versions of "Corner Assist", but eventually concluded that I was trying to solve an architectural problem with more special-case logic.

The current v0.6 approach is closer to:

Camera / perception
        ↓
Persistent world-space path belief
        ↓
Connected-path prediction / look-ahead
        ↓
Planner
        ↓
Controller / safety
        ↓
LinuxCNC motion

The design principle that came out of that work is:

**Detectors observe. The model remembers. The planner decides. Motion executes.**

FabScan now tries to understand and follow the connected continuation of the profile rather than simply reacting to the latest local line fit.

## Record/Replay and Simulator

A fairly substantial development framework grew out of trying to debug the follower.

FabScan can now record complete physical tracing runs, including camera frames, calibration, planner state, motion, and diagnostics, then replay those runs deterministically.

Replay was extremely useful, but it has one unavoidable limitation: once a new planner chooses a different path than the old one, there are no recorded camera frames from that new location.

That led to an SVG ground-truth simulator using the exact A-G test geometry.

The simulator runs the real FabScan perception, estimator, and planner against a virtual camera that can move wherever the planner chooses. It also includes measured camera appearance, observation delay, and the actual configured motion limits from my LinuxCNC table.

That has become one of the most useful development tools in the project.

## Latest Real-Machine Result

The current hardest test geometry is shape **G**, which contains straight sections, tabs, a 45-degree corner, a radius, and several sharp direction changes.

The latest physical run completed:

**800 / 800 planner steps with no HOLD**

It stopped only because Count was set to 800, about **0.738" short of completing the loop**.

Some comparison numbers:

M5.6 simulator full path:    21.5182"
M6.2 physical implied path:  21.5091"

Physical RMS error vs SVG:   ~0.00446"
87.6% of path within:        0.005"
96.4% of path within:        0.010"

LinuxCNC itself followed the requested coordinated XY endpoints very closely, with an average endpoint miss of about **0.00045"**.

The remaining larger errors are concentrated around a few sharp vertices where the planner begins turning slightly early.

That is encouraging because the problem is becoming very specific rather than looking like general path instability.

## Where Help Would Be Useful

The biggest current planner question is how best to distinguish:

**continuous curvature / a radius**

from:

**a true sharp connected-path vertex**

For a radius, normal look-ahead following should continue.

For a true corner, I think the planner needs to recognize it, commit to the actual vertex, finish the incoming leg, then latch onto the outgoing leg.

Other areas where ideas or contributions would be welcome include:

* state estimation / Kalman-style approaches
* connected-path association and branch scoring
* confidence models
* machine vision
* diagnostics
* eventual continuous/velocity-based following
* LinuxCNC integration

## HISTORY.md

I added a `HISTORY.md` file to the repository specifically for anyone interested in the development side of the project.

It is a bit longer than the normal documentation, but I think it is worthwhile reading before digging into the planner because it explains **why the current architecture exists**.

It covers:

* the original local follower
* the Corner Assist experiments and why that approach was abandoned
* the move to persistent path state
* why record/replay was added
* why replay eventually led to the simulator
* what the simulator is intended to prove
* what the first physical tests exposed
* the A-G test geometry
* simulation vs real-machine results
* the major open design questions

There is also a condensed decision tree showing how one development problem led to the next.

I am hoping that gives potential contributors enough context to avoid having to reverse-engineer months of experiments from the commit history.

## Alpha Status

The safety philosophy has not changed.

FabScan only commands controlled X/Y tracing motion. It does not control Z, the torch, spindle, THC, Cycle Start, or any cutting process.

The real-machine follower is still deliberately conservative and uses bounded coordinated moves with independent safety checks and HOLD behavior when it cannot identify a continuation it trusts.

I am calling this **alpha** because I think the basic architecture has now been validated well enough in simulation and on the real machine that outside review would be genuinely useful.

If anyone has experience with LinuxCNC, machine vision, robotics, controls, state estimation, path planning, OpenCV, or simply sees a better way to approach part of the problem, I would appreciate comments, criticism, testing, ideas, or pull requests.

The goal is still pretty simple:

**A practical open-source LinuxCNC camera tracing tool that can capture real shop-floor geometry and produce useful DXF without trying to become a CAD system or machine controller.**

It is not finished yet, but I think it is getting close enough to be interesting.

Then you should not need any python code use just rules