Bluetooth is the medium of the first Arobot interface.

The controller (Android device) transfers in regular time slices the movement command.

Transfer command consists of 6 Bytes:

Byte[0]  MagicValue = 0xA5

Byte[1] reserve = 0x00

Byte[2..3] velocity command Left (16 bits signed short )

Byte[4..5] velocity command Right (16 bits signed short )

WLAN connects the Android controller with Raspberry-Pi based robot.

From Controller will be transferred commands, 12 Bytes long, robot sends reply, 12 Bytes long too.

Command:

Byte[1..0] MagicValue = 0xAA55

Byte[2..3] command (16 bits short unsigned)

Byte[4..7] value-1 for command

Byte[8..11] value-2 for command

ROS topics are used as interface between Controller and Raspberry-Pi based robot