Path Scripting documentation.

[onekk]

Hello to All

I'm experimenting with path scripting, but I can't find how to initialize a proper Path job.

I've searched in the forum for discussion, but non is showing how to proper initialize a job.

I've put together some code, but it won't compile without errors.

Edit some working code is done see later on this thread

The work is intended as a test for the path creation in a more articulated project that create some shapes in a parametric way using only scripting and produce some gcode as output.

TIA and Regards

Carlo D.

PS: Happy new year 2021

[spanner888]

There are several links to useful Path scripting in this post https://forum.freecadweb.org/viewtopic.php?f=15&t=51033

[onekk]

Thanks, but None of the links is showing a proper workflow.

Some of the code I've put together are from the hints in that post.

But the documentation is referring to the old way of setting many things, like Tools data.

Plus many of the documentation are referring to the old way of defining things, like pockets and Jobs,

https://wiki.freecadweb.org/Path_scripting

And from the little code I've seen around there is some differences in the workflow.

My main problem is the creation of the Job itself.

As I've wrote in the first post, I was expecting to be able to create an empty job and then populate it with the proper
Tooltable and Operations, eventually defining a Stock and some other things.

But even this "relatively" simple task is not documented in any place, searching in the forum post for pathjob is returning nothing focused.

Regards

Carlo D.

[onekk]

Ok some result achieved, put toghether some code lying around, I have to decompress the Mod directory of my AppImage and analyze sources with grep, to find out some working code that "compiile" without error, not too far from the code posted.

See later on this thread

Regards

Carlo D.

OS: Artix Linux (openbox)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.23578 (Git) AppImage
Build type: Release
Branch: master
Hash: 50c3cbf00579dc4941ca743c25720d016b0453ce
Python version: 3.8.6
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: Italian/Italy (it_IT)

[onekk]

Continuing the search, sadly no developer seem interested in this thread.

I would be able to achieve some simple operations, at least.

Some pocket, some profiles, with Tags (Holding Tab are called in other CAMS).

As the only viable free offline CAM for Linux seems to be FreeCAD, there are other paid software, but they are not actively developed at least for Linux.


Hope someone will step in and gave me some hints.

Thew documentation on site is not useful as it refer to many deprecated part of code.

Regards

Carlo D.

[sliptonic]

Continuing the search, sadly no developer seem interested in this thread.

Not true. I'm following your progress closely. Scripting of Path is something that I want to be easier but I just haven't had much time to dig into it.

Hope someone will step in and gave me some hints.
...
Thew documentation on site is not useful as it refer to many deprecated part of code.

I will try to help if you'll try to help update the documentation as we go.
You might also try to connect with me on the gitter channel. Sometimes real-time chat is more productive.

[onekk]

Somemore progress, many thanks to sliptonic

Code: Select all

import FreeCAD
from FreeCAD import Base, Rotation, Vector
import Part
import Path
import Draft

from PathScripts import PathJob
from PathScripts import PathJobGui

from PathScripts import PathProfile

import PathScripts.PathDressupDogbone as PathDressupDogbone

import PathScripts.PathDressupHoldingTags as PathDressupHoldingTags

from PathScripts import PathGeom
from PathScripts import PathPostProcessor
from PathScripts import PathUtil

import numpy as np

DOC_NAME = "Pippo"
gcodePath = '/tmp/engrave.ngc'

DOC = FreeCAD.activeDocument()

def clear_doc():
    """
    Clear the active document deleting all the objects
    """
    for obj in DOC.Objects:
        DOC.removeObject(obj.Name)

if DOC is None:
    FreeCAD.newDocument(DOC_NAME)
    FreeCAD.setActiveDocument(DOC_NAME)
    DOC = FreeCAD.activeDocument()
    VIEW = FreeCAD.Gui.ActiveDocument.ActiveView
else:
    clear_doc()
    VIEW = FreeCAD.Gui.ActiveDocument.ActiveView

def setview():
    """Rearrange View"""
    DOC.recompute()
    VIEW.viewAxometric()
    VIEW.setAxisCross(True)
    VIEW.fitAll()

EPS = 0.10
EPS_C = EPS * -0.5

VZOR = Vector(0,0,0)
RZO = Rotation(0, 0, 0)

box0 = DOC.addObject('Part::Box', 'Box')
box0.Width = 100
box0.Length = 100
box0.Height = 10

box1 = DOC.addObject('Part::Box', 'Box')
box1.Width = 50
box1.Length = 50
box1.Height = 20
box1.Placement = FreeCAD.Placement(FreeCAD.Vector(25,25,-5), FreeCAD.Rotation(FreeCAD.Vector(0,0,1), 0))

DOC.recompute()

cut = DOC.addObject('Part::Cut', 'Cut')
cut.Base = box0
cut.Tool = box1

DOC.recompute()

# get the upper face?
for i in range(11):
    face = "Face%d" % (i+1)
    f = cut.Shape.getElement(face)
    if f.Surface.Axis == FreeCAD.Vector(0,0,1) and f.Orientation == 'Forward':
        break

job = PathJob.Create('Job', [cut], None)
job.ViewObject.Proxy = PathJobGui.ViewProvider(job.ViewObject)

profile = PathProfile.Create('Profile')

profile.Base = (cut, face)
profile.setExpression('StepDown', None)
profile.StepDown = 3.00
profile.setExpression('StartDepth', None)
profile.StartDepth = 10
profile.setExpression('FinalDepth', None)
profile.FinalDepth = 0
profile.processHoles = True
profile.processPerimeter = True

profile.recompute()

DOC.recompute()

job.PostProcessorOutputFile = gcodePath
job.PostProcessor = 'grbl'
job.PostProcessorArgs = '--no-show-editor'

postlist = []
currTool = None

for obj in job.Operations.Group:
    print( obj.Name)
    tc = PathUtil.toolControllerForOp(obj)
    if tc is not None:
        if tc.ToolNumber != currTool:
            postlist.append(tc)
            currTool = tc.ToolNumber
    postlist.append(obj)

post = PathPostProcessor.PostProcessor.load(job.PostProcessor)
gcode = post.export(postlist, gcodePath , job.PostProcessorArgs)

#ops = DOC.getObject("Operations")
#ops.Visibility = True

DOC.recompute()

print("--- done ---")

Some little quirks to fix but at least path are shown and seems that gcode is useable, more to come

Regards

Carlo D.

[onekk]

More fun on scripting

Code: Select all

T1 = PathToolBit.Declaration(toolspath + "tool1.fctb")

This is a pethod to obtain information from a tool file saved on disk, a bit rough, but it works:

you pass simply a filename with the complete path, in my example the toolspath contain the proper path i.e "/home/user/.FreeCAD/Tools/Bit/"

To use it see in this snippet

Code: Select all

# modify some default ToolController data
tc0 = job.ToolController[0]
tc0.Label = "MyTC1"
tc0.setExpression('HorizRapid', None)
tc0.HorizRapid = "15 mm/s"
tc0.setExpression('VertRapid', None)
tc0.VertRapid = "2 mm/s"

tct1 = tc0.Tool
tct1.Label = T1['name']
#tct1.BitShape = shapepath + T1['shape']
tct1.CuttingEdgeHeight = T1['parameter']['CuttingEdgeHeight']
tct1.Diameter = T1['parameter']['Diameter']
tct1.Length = T1['parameter']['Length']
tct1.ShankDiameter = T1['parameter']['ShankDiameter']
tct1.recompute()
#tct1.ViewObject.Visibility = True

tct1.recompute()

tc0.recompute()

The tooldata from the tool file is composed like :

Code: Select all

{'version': 2, 'name': '3mm Endmill', 'shape': 'endmill.fcstd', 'parameter': {'CuttingEdgeHeight': '17,00 mm', 'Diameter': '3,00 mm', 'Length': '50,00 mm', 'ShankDiameter': '3,17 mm'}, 'attribute': {}}

so the tricks in T1[][] to extract the parameters to put into the proper field of the TC.Tool

Another trick, maybe know but not very documented is in this snippet

Code: Select all

tc0.setExpression('HorizRapid', None)
tc0.HorizRapid = "15 mm/s"
tc0.setExpression('VertRapid', None)
tc0.VertRapid = "2 mm/s"

The trick is that prior of assign a value to the field if it is filled with an expression, you have to set this expression to 'None' and then assign values in the proper format Note the speed units.

There are some quirks as the toolshape chisen by default Endmill in this case is not perfect I haven't found yet a manner to change it say to ballnose.

The other doubt is the file property of the ToolController.Tool part.

But for now it seems quite useable to make some scripting.

Main concerns for now are the tool shape and to find a way to apply the Tags dressup to a profile.

At least for the scope of my project, a total way to automate MOP (Machine OPerations as they are called by other CAMs) starting from a parametric object created totally in a script.

More to come

Carlo D.

[spanner888]

More to come

Bump...any more yet? Just starting to look at some path toolbit, feeds and speeds coding, so any help, in addition to above, and that from others I have found in forum is very helpull!

[onekk]

Sorry no progress since then, I'm busy with some other project.

Some work on sources was blocked due to the release of 0.19 so you have to wait some more, to have some news on this arguments.


Regards

Carlo D.