finani/jpl_remote_drone

JPL Remote Drone Setup (using PX4, T265)

• DJI F550
• Nvidia Jetson Xavier NX
• Intel Realsense T265
• OptiTrack (Motion Capture System)
  • Use tf_mocap instead of tf_rs

Topic Flow

1. Change rostopic from /camera/odom/sample to /mavros/vision_pose/pose
   • roslaunch tf_rs tf_rs.launch
2. Estimate precise local position /mavros/local_position/pose in PX4
   • You can also use /mavros/local_position/odom

To Do

1. Set symbolic link (optional)
   • It will link /dev/ttyUSB0 to /dev/ttyPixhawk
   • https://github.com/finani/WeeBee/tree/master/tty_symlink
     • You can check tty using ls /dev/tty*
     • The tty name depends on the connection order. If you connect an Arduino first and then PX4, the Arduino is set as ttyUSB0 and the PX4 is set as ttyUSB1. The tty name changes frequently because you can not connect the devices sequentially each time. So, you need to set up a symbolic link for a stable system. (Many devices use FTDI chip and they use a serial communication.)
2. Set PX4 Telemetry parameters
   • https://dev.px4.io/master/en/companion_computer/pixhawk_companion.html
   • Set MAV_1_CONFIG to Telem2, MAV_1_MODE to Onboard and SER_TEL2_BAUD to 921600
   • Reboot PX4
3. Edit mavros px4 launch
   • sudo gedit /opt/ros/melodic/share/mavros/launch/px4.launch
   • Set fcu_url to /dev/ttyPixhawk:921600
     • <arg name="fcu_url" default="/dev/ttyPixhawk:921600"/>
     • address: /dev/ttyPixhawk (or /dev/ttyUSB0)
     • baudrate: 921600 bps
4. Set PX4 Vision parameters
   • https://docs.px4.io/master/en/computer_vision/visual_inertial_odometry.html
   • Set EKF2_AID_MASK to 24 (vision_position_fusion, vision_yaw_fusion)
   • Set EKF2_HGT_MODE to 3: vision
   • Reboot PX4

How to Run

1. Run mavros
   • It will connect to PX4
   • roslaunch mavros px4.launch
2. Run T265
   • It will start to estimate local position
   • roslaunch realsense2_camera rs_t265.launch
3. Rename rostopic
   • It will link the T265 topic(data) to mavros(PX4)
   • roslaunch tf_rs tf_rs.launch
4. Send a command (optional)
   • It will send a command to move the drone
   • roslaunch offboard_drone offboard.launch
5. Make a command (optional)
   • It is a mission planner
   • It will make a command to control the drone
   • roslaunch ??? ???.launch

Preflight Check

1. T265 odometry (/camera/odom/sample)
   • Check the value and the direction
   • It is required only once at the first time
2. Mavros local position (/mavros/local_position/pose or /mavros/local_position/odom)
   • Check the value and the direction
   • It is required only once at the first time
3. Mavros state from offboard.launch
   • Check the data (connected, armed, guided, flight_mode, cur_position)
   • It is required every time
4. Command output from offboard.launch
   • Check the command (usually velocity) output
   • It is required when running the new algorithm
5. Fly safely~