Bitcraze Forums

Hello all,
Long time lurker here.

Finally decided to work on a small project using a modified crazyflie, odroidXU4 and AR tags. So I'm trying to implement online autonomous control on the crazyflie using AR Tags and an odroid as my computer. I am using the AR track alvar package in ROS along with a webcam to get the relative pose of my camera.

Having done that I don't know the next step I need to take to achieve autonomous flight. Here are some of the questions I have:
1. How do I implement the control for the system ? Do I have to edit the kalman_estimator.c file for this? Can I implement a python script and implement a high level control and feed that directly to the system?
2. How do I send commands from odroid to the imu of the crazyflie? For eg: the pose estimate I'm getting from the marker detection?

Any pointers would be highly appreciated.

Thanks.

Cheers!

Since you are already using ROS, you can use crazyflie_ros (https://github.com/whoenig/crazyflie_ros). The requestBatching branch also supports communication via USB, so you can connect the Crazyflie to the ODROID just via USB for data and power.

The package does not use the kalman filter yet. As part of the crazyswarm project, there is an experimental version using a much better position controller and sensor fusion, but it lacks documentation and requires custom firmwares as of now.

On the firmware side, a port has been added to inject position information in the kalman filter, it is intended to be used with mocap systems (https://github.com/bitcraze/crazyflie-f ... position.c). You might be able to easily modify the ROS crazyflie driver to send this packet to the Crazyflie.

This area is still in heavy development and I guess we will have more change coming from Crazyswarm and the LPS work in the future. But in the mean time the kalman filter and the external position port have been tested successfully.

Quick update, Mike from ETH has made a pull request for the external position port: https://github.com/whoenig/crazyflie_ros/pull/47/files