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Note: This tutorial assumes that you have completed the previous tutorials: Network setup for controlling multiple robots from a remote machine.
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Launch and control multiple robots from a remote machine

Description: This tutorial explain how to launch and control multiple robots from a remote computer

Tutorial Level: INTERMEDIATE

Next Tutorial: Network setup for controlling multiple robots from a remote machine

Preliminary Setup

Install the ric meta-package

The base station computer should have the entire ric meta-package built. You should also run and answer 'y' (yes) to all steps of the setup.sh file (follow the Robot installation tutorial).

Network setup

Follow the Network setup for controlling multiple robots from a remote machine tutorial.

Launching the robots

For the following examples we assume we have two komodo robots with id's 1 and 2 with IP addresses 192.168.0.101 and 192.168.0.102 respectively. The base station computer IP address is 192.168.0.100. One can use any other IP addresses.

First, we will edit the ric/ric_base_station/launch/komodo_base_station.launch file to match the above komodo robots addresses:

   1 <machine name="komodo1" address="192.168.0.101" user="komodo" password="a" env-loader="~/catkin_ws/src/ric/ric_robot/config/ric_env.sh" default="true"/>
   2 
   3 <group ns="komodo_1">
   4    <include file="$(find ric_base_station)/launch/remote_komodo.launch">
   5    <arg name="id" value="1" />
   6    </include>
   7 </group>
   8 
   9 
  10 <machine name="komodo2" address="192.168.0.102" user="komodo" password="a" env-loader="~/catkin_ws/src/ric/ric_robot/config/ric_env.sh" default="true"/>
  11 
  12 <group ns="komodo_2">
  13 <include file="$(find ric_base_station)/launch/remote_komodo.launch">
  14 <arg name="id" value="2" />
  15 </include>
  16 </group>

Make sure that the <machine/> parameters are all correct according to your network setup and to the specific robot computer username and password. Note that from the factory the default username is "komodo" and password is "a". .

In order to select exactly what will be launched on the komodo robots, see the ric/ric_base_station/launch/remote_komodo.launch file.

In a terminal window, set the following parameters according to the base station IP address:

$ export ROS_MASTER_URI="http://192.168.0.100:11311"
$ export ROS_IP="192.168.0.100"
$ export ROSLAUNCH_SSH_UNKNOWN=1
$ roscore

You will have to type the first two export commands in each new terminal window.

To watch the start-up messages, run rqt_console in a new terminal:

$ rqt_console

Finally, in a new terminal, launch the base_station launch file:

$ roslaunch ric_base_station komodo_base_station.launch

If you have any problems during the launch, check your network setup.

Now you can control all the komodo robots, try printing the current topics to check that everything is ok:

$ rostopic list

Controlling the robots

One can use the multi_robot_control node to control multiple robots from a single joystick.

The ric/ric_base_station/launch/multi_robot_control.launch is used to launch the required parameters and start the node.

You will have to figure out your joystick port and the id numbers of joystick axes and buttons. To do so, type:

$ ls /dev/input

and find the joystick port name (usually /dev/input/js0).

Now run:

$ sudo jstest /dev/input/js0

Play with joystick sticks and buttons and write down the numbers of the axes which you would like to control the drive and the axes to control the pan-tilt system. You should also choose a button for switching between robots (joy_scroll_btn), a button to switch between slow and normal drive speeds (joy_slow_btn) and a button for centering the pan-titlt system (joy_center_btn).

Edit the multi_robot_control.launch to match the joystick port.

Now, edit the ric/ric_base_station/config/multi_robot_control.yaml file to mach your required axes and buttons.

Launching the multi_robot_control.launch file can be done manually:

$ roslaunch ric_base_station multi_robot_control.launch

or as a part of the komodo_base_station.launch:

<include file="$(find ric_base_station)/launch/multi_robot_control.launch"/> 

Now you can manually drive and operate the pan-tilt system of all the robots.

You can watch the robots cameras and sensors using rqt.

Have fun!


2019-07-20 13:06