pi_dash - automotive (rally) dash written in Elixir and React that runs on Raspberry Pi

pi_dash is an application that can replace your cars standard gauges with customizable dashboard where you can choose which reading you would like to see.

The reason this project came to life is that my amateur rally car was lacking a tachometer, coolant temperature etc gauges, which would be quite helpful in extreme rally conditions.

In the beginning I only wanted to make a simple tachometer, but then decided to go full in and came up with this.

Note:

The project is still in development and was tested only on several cars.

Features

• Automatically finds and configures ELM device
• Currently supported OBD PIDs:
  • RPM
  • Vehicle speed
  • Intake temp
  • Throttle position
  • Timing advance
  • Engine load
  • Coolant temp
• Selectable intervals for data collection
• Light and night mode GUI
• Draggable and resizable gauges
• Selections of gauges and layout are not lost upon restart
• User configurable max RPM range

High level overview

You can run the software from you computer first to see how it works with your car.

Installation

Untar the latest release to /home/$USER/. From /home/$USER/pi_dash/bin/, run:

./pi_dash start

or

./pi_dash daemon

for detached mode.

Configuration

Custom configuration parameters are located in

/home/$USER/pi_dash/releases/x.x.x/env.sh

Run on specific serial port

If pi_dash doesn't find a supported ELM device to connect to it will try on specific serial port. If your ELM device is not supported (e.g. does not auto-detect) you can edit the env.sh file and change SERIAL_PORT environment variable to you port, for example:

export SERIAL_PORT="/dev/pts/2"

Max RPM (default 6500)

Since all cars are different it is possible to set your own value for maximum RPM your engine can have. In env.sh change the value to match your car:

export MAX_RPM=6500

Debug logs

For problems reporting and debugging in "production" you can change LOG_LEVEL variable to debug:

export LOG_LEVEL=debug

In order to see extra stuff like how the message is decoded and what are the translated values, change this to true:

export EXTRA_LOGGING=true

Note:

EXTRA_LOGGING=true will only take place if LOG_LEVEL is set to debug

If you change any values in env.sh, you need to restart the application with:

./home/$USER/pi_dash/bin/pi_dash stop
./home/$USER/pi_dash/bin/pi_dash daemon

or reboot your Raspberry Pi.

Raspberry Pi configuration

OS installation

Chromium in kiosk mode and autostart

Autostart application

After following instructions in Chromium in kiosk mode and autostart edit sudo nano /etc/xdg/openbox/autostart and add one line to start pi_dash on boot:

/home/$USER/pi_dash/bin/pi_dash daemon

Hibernate mode (car engine off)

TBD

Development mode

Install ELM327-emulator and run with python3 -m elm, then run command scenario car. Note the serial port and change it in config.exs. Run make test_mode, in browser open localhost:4000.

Building from main

Since the target platform is Raspberry Pi the application has to be built with that architecture in mind. I've tried to use docker buildx, but so far didn't succeed.

You can fork this repo, install GitHub's action-runner and use .github/workflows/build_on_rpi4.yml to build it on your own RPi4.

Before running the workflow, do the following:

1. label your runner as rpi4
2. on RPi you need to install 3 packages. I recommend using asdf. You will need Erlang and Elixir as well as nodejs.

TODO:

• Hibernate RPi when the car engine is off (or by external button flip)
• Handle reconnect when engine is off
• Longer tests with car to test stability of the application, deadlocks etc
• Add support for ELM devices from different manufacturers
• Enhance GUI: support for different gauge types. Make it more flashy? Add theme support?
• Create img file with all above configuration ready to burn on SD card for RPi, guide or can Nerves do the same?