Atlas Scientific makes an amazing suite of scientific grade environmental monitoring sensors that have a perfect synergy with the Plotly data visualization platform.
This Instructable will show you how to hook up an Atlas Dissolved Oxygen sensor and a Raspberry Pi to Plotly’s real-time graphing platform. You will view your data in real-time in your web-browser! Here is our final product: A graph of our dissolved oxygen sensor in our Montréal office: http://plot.ly/~streaming-demos/52/!
You can also use Atlas’s pH, ORP, and EC sensors simply by swapping out the appropriate circuit and probe. Calibration functions will vary for each sensor. This will work with the Arduino Yun, Beaglebone Black, or any other embedded linux platform.
Step 1: Hardware You Will Need
- Raspberry Pi
- Raspberry Pi Budget Pack
- SD Card
- Micro USB Power Adapter
- Pi Cobbler
- Raspberry Pi Case
- Atlas Dissolved Oxygen Kit
- Dissolved Oxygen Circuit
- Dissolved Oxygen Sensor
- BNC Connector
- Ethernet Cord
Step 2: Setup Raspberry Pi
- Load Raspbian onto your SD card. There are plenty of tutorials out there on this. Here’s a good one: http://elinux.org/RPi_Easy_SD_Card_Setup
- Insert SD card into the Pi, plug in the micro USB power adapter, and connect the Ethernet cord to the Pi and your local router.
- SSH into your Raspberry Pi. (To quickly find the IP address assigned to the Pi, I like using the Fing app on my iPhone.)
- Setup the serial port and download appropriate libraries:
Open the /etc/inittab file:
Add a ‘#’ at the beginning of the following line so that it looks like this:
#T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt10
Run the following commands in your Pi’s terminal:
sudo apt-get install python-serial
sudo apt-get install git-core
sudo apt-get install python-pip
sudo pip install rpi.gpio
sudo pip install plotly
Reboot the Pi:
Step 3: Sign Up With Plotly
- Go to https://plot.ly and sign up for an account!
- Once you sign up and sign in, go to your settings: https://plot.ly/settings or in the drop-down on the top right in https://plot.ly
- Take note of your API Key
- Click the Stream Tokens tab, then click Generate token
- Take note of your Token
Step 4: Clone the Atlas-Scientific Repository
Clone the Repository from Github:
git clone https://github.com/plotly/atlas-scientific.git
Open the Directory:
Or just copy the code from the files here: https://github.com/plotly/atlas-scientific
Step 5: Add Username, API Key, and Streaming Token
Fill in your Username, API Key, and Streaming Token.
Here is an example of what it should look like in the file:
token = '5jpi07w226' username = 'arkeon' api_key = 'u6jlwbypiq'