node-multidrone

Node.JS program to configure AR Parrot drones to share a Wifi network

Based on instructions from http://drones.johnback.us/blog/2013/02/03/programming-multiple-parrot-a-dot-r-drones-on-one-network-with-node-dot-js/

How Drone Control Works

Parrot AR drones each form their own wifi network, and by default use the static IP 192.168.1.1. To control a drone, your client device connects to the same wifi SSID as the drone, and sends commands to the static IP.

Drones run Linux and have an open telnet server running on port 23 with a BusyBox shell. Any telnet client can connect without any authentication to get a root shell on the drone.

Drone network config is spread across two files:

• SSID setting is in /data/config.ini as the ssid_single_player key
• Wifi mode (1=adhoc, 0=infrastructure) setting is in /data/config.ini as the wifi_mode key
• IP address is in /bin/wifi_setup.sh as the PROBE variable. This is the IP under the 192.168.1.X network to take. This defaults to 1.

To apply changes to the drone network config, execute /bin/wifi_setup.sh. The drone will restart the network and come up with the new SSID and IP address.

Example

Imagine your drone is currently set to SSID roboenemy and it has static IP 192.168.1.1.

Let's say we want to change a drone's SSID to robofriend and set it to use the static IP 192.168.1.200, you could do the following:

• Connect computer to wifi network roboenemy
• Telnet to 192.168.1.1 (telnet 192.168.1.1 in UNIX shell)
• Edit /data/config.ini changing ssid_single_player value to robofriend
• Edit /data/config.ini changing wifi_mode value to 1
• Edit /bin/wifi_setup.sh changing PROBE=1 to PROBE=200
• Run /bin/wifi_setup.sh to restart drone networking

Drone should now kick you off and restart its wifi network.

In a few seconds, you should be able to connect to wifi network robofriend and telnet to 192.168.1.200.

Success!

Multiple Drones

To control multiple drones, you need to establish the following conditions:

• Each drone must be on the same SSID
• Each drone must be set to adhoc Wifi mode
• Each drone must have a separate static IP on the same network
• Client machine must be on same wifi network as drones
• Client machine should send control commands to the different IPs of drones.

Mac OS X Note:

Macs seem to be finnicky with ad-hoc wifi networks. If you get an error connecting to the ad-hoc network after configuring your drones, try rebooting your Mac.

Scripts

Script to change IP and SSIDs on the Drone:

IP=200
SSID="my ssid"

WIFI_SETUP=/bin/wifi_setup.sh
DATA_CONFIG=/data/config.ini
    
# copy current wifi_setup.sh to backup
cp -p $WIFI_SETUP $WIFI_SETUP.old
sed -e "s/PROBE=.*/PROBE=$IP/g" $WIFI_SETUP.old > $WIFI_SETUP

# copy current config.ini to backup
cp $DATA_CONFIG $DATA_CONFIG.old
sed -e "s/\(^ssid_single_player.*=\).*/\1 $SSID/g" $DATA_CONFIG.old > $DATA_CONFIG
# set wifi_mode to 1 for adhoc network
cp $DATA_CONFIG $DATA_CONFIG.tmp
sed -e "s/\(^wifi_mode.*=\).*/\1 1/g" $DATA_CONFIG.tmp > $DATA_CONFIG
rm -f $DATA_CONFIG.tmp

# apply the new network config
echo !!!! Reconfiguring drone.
echo !!!! You will be disconnected.
echo !!!! Reconnect to wifi network.

$WIFI_SETUP