TVMD Model Preview and Flight Review

This project establishes basic simulation environment for TVMD in GZ-Sim.

Features

• Generation of TVMD sdf model (for GZ-Sim)
• Preview of TVMD model in Rviz
• Convert the ulog file to rosbag file, which can be used to replay the flight in Rviz

Quick Start

To build this project:

catkin_make
. ./devel/setup.bash

Note that if the topics in src/px4_msgs/msg are modified, you need to make a clean build.

Model Preview

Use Rviz to inspect the model:

roslaunch tvmd display.launch

• This will launch Rviz with TVMD model and start the republisher.

Flight Review

This feature works for SITL and real flight logs.

1. Convert the ulog file to rosbag file using the provided script:

   ./ulog2bag.sh -f <ulog_filename>.ulg

   This will create a rosbag file in the same directory as the ulog file.
2. Launch rviz with TVMD model and start the republisher:

   roslaunch tvmd display.launch

   The rosbag file can be published using PlotJuggler, and display.launch will start the republisher node to initialize Rviz and subscribe topics in rosbag i.e.,px4/actuator_motors and px4/actuator_servos.
   • Note: launch display.launch first to start a ROS master for PlotJuggler.
3. Open PlorJuggler, go to the Publisher tab, click the ROS Topic Re-Publisher button, and select the topics to republish.
   • The two topics are republished to /joint_states, which is the control input of the model in Rviz.

If the firmware is compiled in control allocation debug mode, the ControlAllocationMetaData topic will be available in the rosbag file. This topic contains the control allocation pseudo-forces and the calculation intermediate variables, which are helpful in debugging. The republisher node will publish this topic and convert them to /visualization_msgs, such that this data can be displayed in Rviz.

Additional Tools

SDF File Generation

To generate the SDF file for GZ-Sim:

sh ./tools/gen_sdf.sh

ULog File Conversion

The conversion is done by tools/pyulog/pyulog/ulog2rosbag.py. Please follow the instruction in tools/pyulog to install the tool. A script is provided to facilitate the conversion:

./ulog2bag.sh -f <ulog_filename>.ulg

Args:

• -f: specify the ulog file to convert
• -a: specify the topic to convert (default: control_allocation_meta_data,actuator_motors,actuator_servos, etc.)

Note that this feature requires a ROS environment with px4_msgs built and sourced. And the px4_msgs package should have ControlAllocationMetaData.msg in px4_msgs/msg, which can be obtained in TVMD-UAV/TVMD-PX4.

Visualization of Flight Logs

python3 draw_attitude_error.py <path_to_ulog>