Usage

The crazyflies package provides a convenient launch file (framework.launch.py) which allows you to launch with hardware, webots or mixed crazyflies.

1. Sourcing (needs to be done in every new terminal):

   source install/setup.bash
   export WEBOTS_HOME=/usr/local/webots
   

2. Launch the framework with:

   ros2 launch crazyflies framework.launch.py backend:=webots
   

   Select hardware, webots, or both as your backend.

3. When starting with webots or both. Only the backend for the simulation is started. You need to open Webots seperately and select the provided world (see Installation). (The Framework will then connect as extern controller to the Webots simulation).

4. Now it is time to connect your first crazyflie:

   ros2 service call /crazyflie_hardware_gateway/add_crazyflie crazyflie_hardware_gateway/srv/AddCrazyflie "id: 0
       channel: 100
       initial_position: [0.0, 0.0, 0.0]
       type: 'default'"
   

   The result should include a success: true.

   Note

   For webots the command looks slightly different. The service is then called crazyflie_webots_gateway/add_crazyflie. Use TAB-autocompletion to autofill the type and fields.

5. When the crazyflie is connected, you can use the high level commander to control the crazyflie:

   • Takeoff

     ros2 topic pub /cf0/takeoff crazyflie_interfaces/msg/Takeoff "group_mask: 0
         height: 0.5
         yaw: 0.0
         use_current_yaw: false
         duration: 2.0" --once
     

   • goTo

     ros2 topic pub /cf0/go_to crazyflie_interfaces/msg/GoTo "group_mask: 0
         relative: true
         linear: false
         goal: [1.0, 0.0, 0.5] # TODO
         yaw: 0.0
         duration: 2.0" --once
     

   • Land

     ros2 topic pub /cf0/land crazyflie_interfaces/msg/Land "group_mask: 0
         height: 0.0
         yaw: 0.0
         use_current_yaw: false
         duration: 2.0" --once
     

Crazyflie / Safeflie

If you want to start scripting your own application logic, you can use the crazyflies package to create a Crazyflie or Safeflie. Familiarise yourself with the Crazyflie and Safeflie classes (the crazyflies package).

You can start your first Safeflie with:

ros2 launch crazyflies safeflie.launch.py id:=0 channel:=100 initial_position:=[0.0,0.0,0.0] type:=2

• id: The id of the crazyflie.

• channel: The channel of the crazyflie, if a real crazyflie is used.

• initial_position: The crazyflies initial position, if a real crazyflie is used.

• type: 1 if you want to connect a hardware crazyflie. 2 if you want to connect a webots crazyflie.

The safeflie will automatically use the hardware or webots gateway to add the crazyflie. (no service call add required).

Note

Creating a Crazyflie/Safeflie will automatically set it up to be tracked by a motion capture system, but this is subject to change. If you instantiate a Crazyflie using the gateway (see Usage /Architecture), then you may provide a type field.