This is a server script which controls the Raspberry pi rover. For an implementation overview refer to the video below.

The rover is controlled by Raspberry Pi Zero W, with Raspbian-jesse distribution installed. The rover actions are controlled by rover.py script. The script is ran as an unprivileged user rover who is a member of dialout and shutdown groups. The dialout group membership is needed for serial port operations, the shutdown groups was added to manage permissions for the shutdown command, which were granted by adding the following line in the sudoers file via visudo command:

%shutdown ALL = NOPASSWD: /sbin/shutdown

###Bluetooth Gotchas The rover implementation uses Bluetooth Serial Profile, which is NOT enabled by default. In order to fix it there are a few modifications required for the systemd bluetooth service:

1. add compatibility option -C to the bluetoothd
2. add serial profile using sdptool command

The above requirements are reflected in the following 2 lines of your systemd bluetooh.service script:

ExecStart=/usr/lib/bluetooth/bluetoothd -C and ExecStartPost=/usr/bin/sdptool add SP

In Pi Zero W the Bluetooth is ran on the serial inteface /dev/ttyAMA0. However, you will not be able to connect to it directly. The tricky part is the way RFCOMM sockets are implemented on Linux. By default the Bluetooth device (ran on the /dev/ttyAMA0) will be listening for a connection, using rfcomm listen hcXX, or rfcomm watch hcXX commands, where hcXX is your Bluetooth interface. Once connection is acceptied the Bluetooth stack will create another serial inteface, usually /dev/rfcomm0, and hand over the connection to it. The /dev/rfcomm0 inteface is owned by the dialout group, hence the required group membership mentioned above.

The systemd rover-setup.service takes care of setting up a connection listener by running rfcomm watch hci0. The rover.service launches the rover.py script, which communicates via /dev/rfcomm0.

Please refer to the rover-setup.service and rover.service files