11. Frequently Asked Questions - larry-athey/rpi-smart-still GitHub Wiki
Q: Is it possible to buy this system as a kit or pre-assembled turn-key solution?
A: Not at this time, but anybody is more than welcome to provide them and I will publish their contact information here. I'm 50% blind and nearing retirement age, so I don't have it in me to start up this kind of business. The only things that I will be selling are prepped and tested RPi Smart Still Hats, LIDAR Hydrometer Readers, and 3D printed parts from the /3D-Models/ directory at https://panhandleponics.com/technology-assisted-distillation/
Q: What do you recommend for Raspberry Pi support since their official forums are pretty much useless?
A: I recommend watching YouTube videos and using an AI chatbot if you have a question that you want a fast answer to. My AI preference is Elon Musk's Grok because it actually provides you with extensive detailed answers. That feature alone makes the yearly X Premium subscription worth the money. The Arduino forums are just as bad, both of them are over-run with soy bitches who have been there since the beginning and all they're good at is belittling people and answering questions with "Google is your friend". Don't waste your time with forums, Reddit, etc. YouTube and an AI chatbot are all you need. AI has already read and indexed pretty much every web forum by now anyway.
Q: Out of all the Raspberry Pi clones out there, which one would be your recommendation?
A: I don't know about all of them out there, I can only speak on the ones that I own. Out of the box, I can say that the Banana Pi M4 Berry is my preference for this project. Mine has 2GB of RAM and built-in 8GB eMMC storage. I installed the desktop version of Armbian Bookworm on it, cleaned out all of the unnecessary apps (Chromium, LibreOffice, Visual Studio Code, etc) then installed the code for this system. After that, I used the feature in armbian-config to boot from the eMMC and it still had 1.5GB free after copying the SD card to it. Everything runs way faster than it does from the SD card, which can then be removed. It actually way out-performs an original Raspberry Pi Model 4.
Q: Does this system have an automatic updates feature?
A: Yes, if you look in the rpi-smart-still/Undercarriage directory after you run the git clone command, you will see an auto-update script. Copy the file to /home/pi/auto-update on your system and create a CRON job to run it. The example CRON job in the comments at the top of the script run it at 3am every day. Adjust that time as necessary if you want it to run at the different time.
Q: If you can't do automatic cuts based on flavor compounds, can you make cuts by volume?
A: That would be a separate project and not something that the RPi Smart Still system would control. A person could very easily create a turntable or conveyor to move collection jars, but determining how full they are is tricky because distillate is colorless and nonconductive. Water level sensors rely on minerals in the water to make it conductive, this is why they monitor electrical conductivity in hydroponics. When you distill water, the minerals are left behind in the still. The only option I can think of here would be to monitor a float in the collection jar, which would involve some basic robotics to lift and lower it every time there's a jar change.
Q: I have a brand new Orange Pi with a fresh OS installation and it keeps going into suspend mode, how do I fix it?
A: Yep, that has to be the most stupid feature ever thought of. These little computers only pull 5 watts at the most under extreme load, what the hell were they thinking? An LED porch light pulls more power! Disabling the power management feature in desktop versions also doesn't fix this, but it can be fixed at the command line. If you leave a terminal idle, you will still see the warning about it being about to suspend, but it never happens. I'm not sure where that warning is coming from.
sudo nano /etc/systemd/sleep.conf
Add the following two lines to it.
Suspend=0
Hibernate=0
Then run the following command.
sudo systemctl daemon-reload
Q: I bought a stepper motor with a gear box for my propane burner, how do you turn one of those by hand?
A: You won't be able to unless the back of the motor has the shaft exposed. Otherwise, you'll need command line access to your Raspberry Pi and manually run the heating stepper executable to turn it. Just execute the following command in a terminal with no parameters and it will display its required parameters on the screen. Make a note of your use of the CW and CCW parameter, if you have to use CCW to turn your heat up, you need to invert the stepper rotation in the heating configuration section in the user interface.
/usr/share/rpi-smart-still/heating
Q: I'm building a new system, how do I make sure that my cooling valves are in the fully closed position?
A: SSH into your device or open a terminal at its desktop if you are working with a full OS installation. You can run your valves from the command line. Just execute the following command with no parameters and it will display its required parameters on the screen. Run your valves closed until the limit switch stops each one. Blow air through the valve to make sure that it's closed. If it isn't, you need reverse the polarity of the wires connected to the L298N motor driver terminals.
/usr/share/rpi-smart-still/valve
Q: Why does the percentage of the valve positions fall back 39.8% or so when I open them to 40%?
A: This is because the last time that you ran the valve calibration, the number of pulses per 0.1% of movement didn't calculate out to an even number. This doesn't affect the operation or reliability of anything. All valves are different, even if they're the same brand and model. It's possible that the next time you calibrate them, they will calculate differently.
Q: /dev/ttyAMA0 disappeared in Raspbian 12, how do I change the hydrometer to the new /dev/serial0 device?
A: You need to edit the file /usr/share/rpi-smart-still/config.ini on your Raspberry Pi and change the serial device in there. The configuration variable named HYDRO_PORT needs to be changed to point to the correct serial device. Also keep in mind that this will only work on a model 5 or later or a USB serial port adapter on older units. Raspbian 12 broke onboard serial UART support on GPIO 14/15 for any "Legacy" boards, as they now refer to them (Jackasses).
Q: What's the best material to use for the reflector with the LIDAR Hydrometer Reader?
A: In all honesty, black heavy construction paper. You want something that you can easily keep flat, with no glossy finish, and as dark as possible. Another alternative is a standard stock business card that you spray paint flat black.
Q: Do you have a link for a hydrometer with a 112mm scale?
A: Yes, https://www.amazon.com/dp/B013S1VAM4 is my goto hydrometer. The LIDAR sensor has a 25 degree cone shaped field of view, the further you get away from it, the larger its pickup pattern. Shorter scale hydrometers such as this reduce the possibility of the glass stem from being picked up by the sensor and causing erroneous readings.
Q: Why does my LIDAR Hydrometer Reader start showing erratic readings at 40% and below?
A: You could be picking up reflections from the stem of your hydrometer. You can solve this by flipping the 3D printed sensor mount over and mounting the sensor to the flat side. You might also need to use a slightly larger reflector after this, but probably only 1mm or 2mm larger in diameter. Also, make sure that your parrot is level so the hydrometer stem doesn't lean toward the sensor. Lastly, keep in mind that the LIDAR sensor only measures in 1mm increments. The lower you go in ABV, the closer the 1% lines are together and they're less than 1mm apart, so an estimate needs to be performed based on the hydrometer's current position between the two 10% divisions.
Q: Why doesn't my flow sensor ever register a value?
A: The flow sensor will show 100% at 1/2 liter or 16oz per hour. If your still is only putting out a mild trickle, then you won't have enough flow to turn the impeller. If you know of another flow sensor that works at lower volumes, please provide me a link to it. With distillate being clear and non-conductive, I can't optically or electronically count drops. I'm still trying to think of a way to measure this without the use of moving parts.
Q: Is there a mobile app for this?
A: Just the web browser on your mobile device which needs to be on a WiFi connection to the same network that your RPi Smart Still controller is connected to. This isn't something that you'd want to have public internet access into, so there will never be any mobile app or cloud connectivity built in.