Communication failure with multiple crazyflies

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davids
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Joined: Thu Mar 09, 2017 2:32 am

Communication failure with multiple crazyflies

Post by davids » Wed Jun 28, 2017 2:22 am

Hi all,

I am using 5 crazyflies with 3 crazyradios in ROS. Following the instructions, I am using the latest firmware (for the cf, the radio, and the crazyradio), one channel for each crazyradio and different addresses.

My main problem is that when I send a thrust command to all robots, all of them receive the packages (the communication LED blinks for all of them), but only a few (lets say three) takeoff. The others just keep communicating but do not move the motors.
If I just restart my ROS script, but not the robots, they take off. Then, sometimes they work and sometimes they do not.

I really would appreciate your help and suggestions.

David

arnaud
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Re: Communication failure with multiple crazyflies

Post by arnaud » Wed Jun 28, 2017 9:00 am

Hi David,

What kind of positioning system (if any) and what instruction are you following?

The problem sounds very strange so it would be useful to get a bit more info on what you are running on the ROS side.

davids
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Joined: Thu Mar 09, 2017 2:32 am

Re: Communication failure with multiple crazyflies

Post by davids » Wed Jun 28, 2017 9:12 am

Hi Arnaud,

Thank you for you rapid response. I'm using Vicon. On the ROS side, I checked the bag files and I'm sending the thrust command using the cmd_vel topic.

There is a difference with the crazyflie_driver takeoff. Instead of sending a progressively increasing thrust to take off, I send the thrust that I need to takeoff directly (let's say 45000). Should this affect?

arnaud
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Re: Communication failure with multiple crazyflies

Post by arnaud » Fri Jun 30, 2017 8:26 am

No there should not be any effect with that, if you send the thrust to the Crazyflie they should fly as long as the sensor are calibrated (this can be verified by looking at the blinking rate of the red LED: it starts blinking slowly and when the sensors are calibrated it blinks faster).

Sending a high thrust directly might just result in a bit less controlled take-off but it should take-off.

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