HallEffectSensor

Mefitis

The sensor data gathering and presenting software suite for NDSU's Bison Pullers. Named after the roman goddess of poisonous gasses, this platform allows us to measure sensors all over the tractor. We use this data to improve many aspects of the tractor, including emissions and noise.

Database Design

Database name: data
Each row represents one seconds worth of data. The columns are for each different sensor.

The current sensors are as follows:
Sound_Engine, Sound_Operator, Emissions_Engine, Emissions_Operator, Temp_Engine, Temp_Exhaust, RPM

Arduino Uno 3

Installing

Pre-req: arduino-cli

You can either install the software from the pi or from any other computer. Start by going into the arduino directory.

Next, compile and upload the code:

sudo arduino-cli compile --fqbn arduino:avr:uno arduino.ino
sudo arduino-cli upload -p /dev/ttyACM0 --fqbn arduino:avr:uno arduino.ino

Now simply plug in the arduino to the pi, start the webserver, and everything should be working.

Raspberry Pi

Installation

To install of a raspberry pi, first, install Raspbian Minimal 64-bit OS onto the SD card. Make sure that the username is pullers.

Next, make sure to update the system and then install git and postgresql.

sudo apt update
sudo apt upgrade
sudo apt install -y git postgresql libpg-dev
sudo apt autoremove

Next, configure postgresql by running sudo -u postgres psql. This should take you to a SQL shell. To configure from there, first create a new database called data.

CREATE TABLE IF NOT EXISTS data (id SERIAL PRIMARY KEY, Sound_Engine REAL, Sound_Operator REAL, Emissions_Engine REAL, Emissions_Operator REAL, Temp_Engine REAL, Temp_Exhaust REAL, RPM INTEGER);

Then set the postgres user password.

ALTER USER postgres with encrypted password 'postgres';

You should now be able to exit the SQL shell. Next, setup configure git with whatever username and email you want. Now, you will have to install nix. To do this, simply run sh <(curl -L https://nixos.org/nix/install) --daemon. You should be able to just follow the prompts and it should install nicely.

After installing nix, restart the system.

Now, download the git repo into the home folder using git clone https://github.com/MrGeoTech/mefitis.git.

Finally, setup a python venv at ~/venv. Make sure to add the following python packages: w1thermsensor[async] pyserial psycopg2 gpiozero RPi.GPIO

Running

To run the program on the pi, first go into the pi directory and run nix-shell. This should setup the environment to run the server in. Next, just run sh ./run.sh and everything should start.