Monday, January 6, 2014

Remote observatory using Raspberry PI

One the great strengths of the INDI protocol is that it is based on a Server/Client architecture where commands are sent back and forth in XML over TCP/IP. Therefore, network transparency is built right at the protocol level and it makes distributed data acquisition and control quite trivial.

For the last few months, I have been running all my astrophotography gear (HEQ Mount, QSI CCD, Lodestar Guider, MoonLite focuser) on my HP laptop using INDI & KStars/Ekos. As it was getting quite cold recently (even in Kuwait it gets quite cold!), I found myself using VNC to access the laptop which sits with all my equipment on the roof. While the performance was OK since it is a local network, I was curious to try to use Raspberry PI (RPi) to run the INDI server and drivers, and connect to them remotely from Ekos.

Building and installing the drivers on RPi was straightforward. Due to power limitations of the RPi, I used a powered USB hub to connect all my equipment. That worked pretty well, and to my surprise, everything worked without a hitch from the first time! I used a USB WiFi dongle on the RPi and gave it a static IP address as well.

Connecting to the RPi from Ekos was straight forward, and I was able to carry on 6+ hours of continious image aquisition, guiding, and focusing without any issues! While all my equipment only sit less than 20 meters away, the same principle is applicable to 2000 km away as long as you have a reliable network connection.

For those curious about using RPi with their astro gear, I wrote a tutorial on getting started with INDI & Raspberry PI.


Campbell Muir said...

Just come across this blog you've posted and it's something i've been looking ito for some time and Raspberry Pi has seemed that it might work.
I aslo keep the laptop outside and acess it via Teamviewer but what I wanted to know is, does the RPi just act as a server between your PC and the imaging rig where the actual software is still on the PC or have you looaded the imaging software onto the Pi?
What I would like to do is continue to use Backyard Eyos, PHD and nebulosity and just use the Pi as the inbetween for transfering the signal to the indoors PC.

Jasem Mutlaq said...

The RPi runs the INDI server which performs all the control and acquisition. The data is then transfer to the client (such as Ekos). Therefore, you need a client on your main PC, and a server on the RPi connected to your gear.