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FreeCAD on Raspberry Pi 4
Hey! This is really old! FreeCAD 0.19 is in the Raspberry Pi OS Bullseye repo now:
sudo apt install freecad
FreeCAD 0.18.4 running on a Raspberry Pi 4 FreeCAD and the Raspberry Pi haven’t always got on too well. For complex technical reasons the standard package would load and immediately crash on a Raspbian system. For user reasons, this was just another annoyance.
Recent releases seem to run fairly well on a Raspberry Pi 4, though, but only after building them from source. Here’s a method that got FreeCAD 0.18.4 running for me. It’s lightly modified from FreeCAD forum MartijnD‘s post:
sudo apt install cmake build-essential libtool lsb-release swig libboost-dev libboost-date-time-dev libboost-filesystem-dev libboost-graph-dev libboost-iostreams-dev libboost-program-options-dev libboost-python-dev libboost-regex-dev libboost-serialization-dev libboost-signals-dev libboost-thread-dev libcoin-dev libeigen3-dev libgts-bin libgts-dev libkdtree++-dev libmedc-dev libopencv-dev libproj-dev libvtk6-dev libx11-dev libxerces-c-dev libzipios++-dev qt4-dev-tools libqt4-dev libqt4-opengl-dev libqtwebkit-dev libshiboken-dev libpyside-dev pyside-tools python-dev python-matplotlib python-pivy python-ply python-pyside libocct*-dev occt-draw libsimage-dev doxygen libcoin-doc dh-exec libspnav-dev wget https://github.com/FreeCAD/FreeCAD/archive/0.18.4.zip unzip 0.18.4.zip rm 0.18.4.zip mkdir freecad-build cd freecad-build cmake -DPYTHON_EXECUTABLE=/usr/bin/python2.7 -DPYTHON_INCLUDE_DIR=/usr/include/python2.7 -DPYTHON_LIBRARY=/usr/lib/arm-linux-gnueabihf/libpython2.7.so -DPYTHON_PACKAGES_PATH=/usr/local/lib/python2.7/dist-packages/ ../FreeCAD-0.18.4/ make -j4Notes:
- The only modifications I made to Martijn’s method were in the Python paths in the cmake command. Some of the paths given aren’t valid any more on an up-to-date Buster system
- I built this on a Raspberry Pi 4 with 4 GB of RAM. It takes quite a bit of free storage: I wouldn’t attempt to build this with less than 4 GB free
- make -j4 took 95 minutes, and even with a fan my Raspberry Pi 4 was at 70°C
- Yes, it’s using Python 2.7, but it works
- I’ve got no idea how to make it install properly, but it runs from the freecad-build/bin directory.
If you want to learn how to use it, look at the tutorials: even the Raspberry Pi Foundation have written some. The UK Traffic Cone model you can have: it’s what I made to learn a bit more about FreeCAD. Don’t worry, I’m still on Team OpenSCAD …
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a bad scene, a worse infographic
CBC says that Alberta’s looming multibillion-dollar orphan wells problem prompts auditor general probe. I mean, I’d say it does: estimated costs to clean up abandoned petrochemical wells outstrip the industry cleanup fund by over 132×, so it’s gone way past looming and is well into omnishambles country. But I’m not here to talk about the environmental mismanagement (well, not much: lolRedwater …), but more to talk about CBC’s terrible infographic:
Total estimated liabilities: $30.1 billion; Total security held: $227 million. It doesn’t take Wilkins Micawber to tell you that the result is misery The image is accurate, technically. The estimated liabilities ($30100000000) are 132.6× the total security held ($227000000), and the red square’s length is 11½× (= √132.6) the blue one’s. But people are generally terrible at comparing areas.
Here are the same numbers, but in bar chart form:
They’re not even on the same page, are they?
(Graph badly put together by me in netpbm. Yes, netpbm …)And there’s the problem: it’s too big to comprehend. CBC’s comfortable little chart fits on a page; you can tweet it, even. But reality is a whole lot of scrolling down the page.
Even the manky old pie chart would be better than CBC’s squares-by area:
Securities are a 2.69° wedge. Liabilities, the rest At least pie charts used linear measure as a proportion of the full 360° pie. But comparing areas is hard; in the diagram below, the teal-coloured part is twice the area of the gold part.
Confusing, isn’t it? -
goodbye X10, hello TRÅDFRI …
The old X10 devices were getting really unreliable: seldom firing at all, getting far too hot, bringing a whole lot of not working to my life. So while it was kind of cool to have my lights controlled by an original 256 MB Raspberry Pi Model B from 2012, it was maybe working one schedule out of ten.
So it had to go: replaced by a Raspberry Pi Zero W and a whole lot of IKEA TRÅDFRI kit. I was deeply unimpressed with the IKEA Home smart app, though: you couldn’t use even basic schedules with more than one light cycle per day. So while I know there are lots of clever home automation systems, I wanted to replace my old cron scripts and set about writing some simple command tools. The result is ihsctrl: very limited, but good enough for me. It’s been working exactly as expected for the last week, so I’ll finally get to wade through 8 years of cobwebs and dismantle the old X10 setup. I already miss the 06:30 clonk of the X10 controller turning the front light on — that was my alarm clock (or alarm clonk) every morning.
(old local copy: ihsctrl.zip)
more up-to-date local copy:
2025 update: this still works, if extremely slowly. It takes maybe 15–20 seconds for a command to get through. Sometimes it doesn’t. Retrying is good.
