More issues with hello_world.py

[GideonLombardo]

Hello,

This question is related to discussion #603 . When I run hello_world.py, the Crazyflie will either randomly fly away from its starting point or flip over. I have read the discussion in #603. I have updated by Cazyradio firmware according the instructions on the configuration page. I get a success message when I run the scan:

Found Crazyradio with version 99.55.

I have also made sure to update the Crazyflie firmware.

For reference, I use Vicon Tracker as my motion capture system with unique marker configurations. Currently, I am testing my setup with only one Crazyflie.

I start the crazyswarm server, and I am able to see the CF pose in RVIZ. I get no error messages, and everything appears to work cleanly. I run python3 hello_world.py, and the CF flips over or flies far away. I get a message in the terminal:

YAMLLoadWarning: calling yaml.load() without Loader=... is deprecated, as the default Loader is unsafe. Please read https://msg.pyyaml.org/load for full details.

cfg = yaml.load(crazyflies_yaml)

Warning: No joystick found!

Traceback (most recent call last):

File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_base.py", line 567, in connect

self.socket.connect((dest_addr, dest_port))

ConnectionRefusedError: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_service.py", line 509, in call

transport.connect(dest_addr, dest_port, service_uri)

File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_base.py", line 596, in connect

raise TransportInitError(str(e)) #re-raise i/o error

rospy.exceptions.TransportInitError: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

File "hello_world.py", line 22, in

main()

File "hello_world.py", line 17, in main

cf.land(targetHeight=0.04, duration=2.5)

File "/home/workstation3/crazyswarm/ros_ws/src/crazyswarm/scripts/pycrazyswarm/crazyflie.py", line 209, in land

self.landService(groupMask, targetHeight, rospy.Duration.from_sec(duration))

File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_service.py", line 442, in call

return self.call(*args, **kwds)

File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_service.py", line 512, in call

raise ServiceException("unable to connect to service: %s"%e)

rospy.service.ServiceException: unable to connect to service: [Errno 111] Connection refused

I do not know what is going wrong. If there is another file that needs to be adjusted, or if there is more firmware to be updated, please let me know.

Thank you,
Gideon

[knmcguire]

Hi! I suggested to #603 to share the changed hover_swarm.launch file, so perhaps you could do the same as well?

There is also this mocap_helper.launch file that only outputs the mocap values, to make sure that you get the right values for that too.

[GideonLombardo]

Here is my mocap_helper.launch file:

<?xml version="1.0"?>
<launch>

  <node pkg="crazyswarm" type="mocap_helper" name="mocap_helper" output="screen" >
    <rosparam>
      # tracking
      motion_capture_type: "vicon" # one of vicon,optitrack,optitrack_closed_source,qualisys,vrpn
      motion_capture_host_name: "#######"
      # motion_capture_interface_ip: "######" # optional for optitrack with multiple interfaces
    </rosparam>
  </node>
</launch>

Is there a way that I can see motion capture values after trying the hello_world.py script?

My plan is to redefine my Crazyflies in Vicon and hope that helps with the tracking. As far as the axes go, I am still unsure if my coordinate system matches like it is supposed to.

Another issue I have noticed is that my chooser.py script always says that I have 0.00V, but it is able to do send commands to the crazyflie. Is it possible that the crazyflie is unable to send data back to the Crazyradio?

[GideonLombardo]

I have been able to run the hello_world.py script successfully. However, I do have some questions. The script does not work every time. For example, when the crazyflie coordinate axes do not align with the world axes, the script will sometimes fail. The crazyflie axes defined in RVIZ will sometimes shake and flicker. I have a feeling the inconsistency in stable flight is arising from the "shaky" axes. Is there a known reason why these things are happening? Please let me know.

[aarsht7]

I am facing the similar issues as you are. I am using vrpn with unique markers and it works some times it doesn't most of the time. When it doesn't work, it will just flip over. I tried with send_position_only = True. One strange thing happens when I run the hover_swarm.launch is, it is logging warning no updated pose found for the cf#. But the pose do shown up in rviz. It doesn't flicker much or at least it is not noticeable. I do not know what the problem can be. I have one more thing to ask, if we are using send_position_only = True then the flickering of the axis (angular deviation) should not affect the actual behavior of the flight, right?

[knmcguire]

@GideonLombardo sorry for the delayed answer, but I'm not sure what is going wrong on your end...

This seems like you probably facing a different issue with this. I would advise you start a new discussion per topic, so that it is easier for others to help you with this.

[aarsht7]

I am not sure but it can be the issue of balancing. I found this and this on their official website. I will try it out before my next testing session and update the flipping issue of the CF.