openrowingmonitor/doc/installation.md

Set up of Open Rowing Monitor

This guide roughly explains how to set up your device. I will probably build an automated installation script from this later.

Requirements

• A Raspberry Pi that supports Bluetooth Low Energy (Pi 3 or Pi 4). Probably this also runs on other devices.
• An SD Card, any size above 4GB should be fine
• A rowing machine (obviously) with some way to measure the rotation of the flywheel
  • the WRX700 has a build in reed sensor that I can directly connect to the GPIO pins of the raspi
  • if your machine doesn't have a sensor, it should be easy to build something similar (magnetically or optical)
• Some dupont wires to connect the GPIO pins to the sensor

Software Installation

Set up the Raspberry Pi

• Install Raspberry Pi OS Lite on the SD Card i.e. with the Raspberry Pi Imager
• Connect the device to your network (headless or via command line)
• Enable SSH

Open a SSH-Connection and set up the dependencies

sudo apt-get update
sudo apt-get dist-upgrade
sudo systemctl disable bluetooth
sudo apt-get install bluetooth bluez libbluetooth-dev libudev-dev

Install Node.js

curl -fsSL https://deb.nodesource.com/setup_14.x | bash -
apt-get install -y nodejs

If you want to run Bluetooth Low Energy and the webserver on port 80 without root

sudo setcap cap_net_bind_service,cap_net_raw=+eip $(eval readlink -f `which node`)

Download Open Rowing Monitor and install dependencies

curl -LJO https://github.com/laberning/openrowingmonitor/archive/main.zip
unzip main.zip -d ~/openrowingmonitor
rm main.zip
cd ~/openrowingmonitor
npm install

Configuration and Startup

You should now be able to start the Rowing Monitor: npm start

You should now adjust the rower specific parameters in app/engine/RowingEngine.js to suit your rowing machine.

Automatically start Open Rowing Monitor while booting

Create file /lib/systemd/system/openrowingmonitor.service with the following content:

[Unit]
Description=Open Rowing Monitor
After=multi-user.target

[Service]
Type=simple
User=pi
# Restart=on-failure
WorkingDirectory=/home/pi/openrowingmonitor
ExecStart=/bin/bash -c 'PATH=/home/pi/.nvm/versions/node/v14.15.5/bin:$PATH exec npm start'

[Install]
WantedBy=multi-user.target

Hardware Installation

Basically all thats left to do is hook up your reed sensor to the GPIO pins of the Raspberry Pi.

todo: add a photo of the wired device

Open Rowing Monitor reads the sensor signal from GPIO port 17 and expects it to pull on GND if the sensor is closed. To get a stable reading you should add a pull-up resistor to that pin. I prefer to use the internal resitor of the raspi to keep the wiring simple but of course you can also go with an external circuit.

The internal pull-up can be enabled as described here. So its as simple as adding the following to /boot/config.txt and then rebooting the device.

# configure GPIO 17 as input and enable the pull-up resistor
gpio=17=pu,ip