syntheticminds / raspberrysky

A Python script for steering a Meade LX200 telescope with a Raspberry Pi and PS3 controller.

Raspberry Sky

This is a personal project I've started to improve my knowledge of Python while making something interesting.

The aim is to make the telescope I have inherited steerable via a PS3 controller. The original Autostar II handset it came with packed up and sadly the telescope has been gathering dust ever since. Now, with the help of a Raspberry Pi and a serial connection, the telescope has been revived.

Requirements

• A Raspberry Pi
• A Meade LX200 telescope
• A USB to RS232 cable

A PS3 Sixaxis controller and bluetooth are required for manual control.

Basic installation

$ cd ~
$ sudo apt-get install git -y
$ git clone http://www.github.com/syntheticminds/raspberrysky
$ cd raspberrysky
$ sudo bash install.sh

Controller support

$ sudo apt-get install pi-bluetooth libusb-dev -y

Next, we need a utility that will allow us to pair a PS3 controller with the Pi. At this stage, be sure the controller is plugged into the Pi via USB.

$ wget http://www.pabr.org/sixlinux/sixpair.c
$ gcc -o sixpair sixpair.c -lusb
$ sudo ~/sixpair

With the controller disconnected and powered off, run the following commands.

$ sudo bluetoothctl
discoverable on
agent on

Power-on the controller and it should start talking to the Pi. Copy the MAC address; we'll need it. Enter:

connect [MAC address]

Try the above command again and again if it says not available. If it says Failed to connect then it has worked. Now we make our changes permanent.

trust [MAC address]
quit

TODO: Controller configuration in settings.yaml

Configuration

We use a settings file to tell the script where to look for devices.

$ cd raspberrysky
$ cp settings.yaml.example settings.yaml

$ python3 RaspberrySky.py

Manual controls

The left thumbstick slews the telescope. How far you push the stick determins how fast it slews. The right thumbstick makes small adjustments - ideal for finding and positioning objects in the eyepiece. The left and right triggers focus out and in respectively.

TODO: Camera configuration in settings.yaml