Unable to communicate with Crazyflie using Chooser.py

[imrd1123]

Environment
OS=Ubuntu 20.04 (BitcrazeVM)
ROS=Noetic
Python=3.8.10

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Hi. I'm in trouble with installing crazyswarm.
I'm glad if you help to solve my problem.

This may be a rudimentary question.
I'm trying to connect to crazyflie using chooser.py.
When I turn on the power of one Crazyflie and run chooser.py with roscore running, there is no communication.
("Err" message appears when I click on "battery" etc.)

The settings in allCrazyflies.yaml are as follows.
I am planning to run it on channel 100.

Also, Crazyflie is set to "Ch.100" in cfclient.

The message when chooser.py is invoked is as follows.

I would appreciate it if you could tell me what I am doing wrong.

[jpreiss]

The id field in allCrazyflies.yaml must be the last byte of the radio address in decimal. So if your CF has address 0xE7E7E7E7, then its id should be 231.

Also keep in mind you do not need to have roscore running to use chooser.py, and you cannot use chooser.py if you are already running crazyswarm_server.

[imrd1123]

Hi James

I understand about the id setting and roscore.
I tried it by entering 231 as the id, and was able to communicate successfully.
Thank you very much.

However, I have a question about server.
How do I start crazyswarm_server?
Is it enough to execute the following code?
source ros_ws/devel/setup.bash
roslaunch crazyswarm hover_swarm.launch

When I run the code, the rviz screen comes up,
but it does not seem to be connected to Crazyflie and does not appear in the 3D map.

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↑Sorry I understand why

[whoenig]

• The launch-file starts the crazyswarm_server node
• If nothing shows up in rviz, there might be a connection problem with your external tracking. Are you using motion capture or something else?

[imrd1123]

Hi Wolfgang

Thank you for teach me.
I understand that the following code will bring up the crazyswarm_server node.
source ros_ws/devel/setup.bash
roslaunch crazyswarm hover_swarm.launch

You are right.
I am using Vicon, and was trying to communicate with it unconnected.
After connecting with the communication cable, I filled in the motion_capture_host_name with the correct IP address, and changed the marker name to cf231.
By doing so, I was able to make the cf231 marker appear in rviz.
Thank you very much for your help in solving this problem.

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However, I have another problem, I want to run multiple Crazyflie from one radio at the same time.
I have configured the settings in allCrazyflies.yaml as follows, but I can't get them to communicate properly.
What am I doing wrong?

# ros_ws/src/crazyswarm/launch/allCrazyflies.yaml
crazyflies:
  - id: 231
    channel: 1
    initialPosition: [1.5, 1.5, 0.0]
    type: default
  - id: 231
    channel: 2
    initialPosition: [1.5, 1.0, 0.0]
    type: default

I'm sorry to bother you, but I would appreciate it if you could tell me. Thank you very much.

[whoenig]

Every robot needs to have a unique address. To use a single radio, the channel needs to be identical. If you use multiple channels, they need to be spaced by at least 2 apart. In most scenarios, channels 60-100 are good.

[imrd1123]

Thank you for your answer.
I understand a little about communication rules.
I'll try to set channels spaced 10 (Ch100, Ch110).

[imrd1123]

I'm sorry, I don't know much about communication yet.
I am trying to run two Crazyflie units on a single CrazyradioPA.
I am thinking of using Single marker as the operation method. The devices are set up as follows
by cfclient
　CF_1: Address[0xE7E7E710], Ch.110
　CF_2: Address[0xE7E7E720], Ch.120
allcrazyflie.yaml
　- id:10
　 channel:110
　 initialPosition:[0.0, 0.2, 0.0].
　 type:default
　- id:20
　 channel:120
　 initialPosition:[0.0, -0.2, 0.0].
　 type:default

I started chooser.py in this state, but it could not communicate.
I have set the Address and the id to be the same, but what am I doing wrong?
Please let me know.

[whoenig]

The address is hexadecimal; 10 = "0x0A" and 20 = "0x14", i.e., the first address should be 0xE7E7E7E70A, second should be 0xE7E7E7E714.

[imrd1123]

I did not notice the fundamental mistake. I apologize for this.
I solved the problem successfully and was able to fly the two Crazyflies at the same time.
Thank you very much for answering so many questions.