What is the co-ordinate system of the drone?
The simulated drone uses a X-Forward, Y-Left and Z-Up or NWU system of reference.
Is the camera calibration available?
The camera calibration is published under /uav/camera/left/camera_info.
Is there support for 18.04 LTS and ROS Melodic?
Since all of our testing involved Ubuntu 16.04 and ROS Kinetic, we do not officially support using Ubuntu 18.04 and ROS Melodic but users have been able to use FG with ROS Melodic and Ubuntu 18.04
What are the minimum requirements to run FlightGoggles locally?
At the moment, FlightGoggles requires ~2.4GB of VRAM and has the same underlying requirements as the Vulkan rendering API.
I am having trouble receiving images from FG while using AWS.
Your computer is likely assigned a local IP address behind a NAT. Please follow the instructions from here to setup VPN.
Why does the simulator run very slow with use_sim_time parameter set to true?
FlightGoggles is similar to the Gazebo simulator in that it can scale the ROS clock down if the simulation is running slowly. Thus, your autonomous algorithms will see a constant 60Hz camera in sim time and should experience accurate drone dynamics as long as the camera renderer is able to run (see ROS clock documentation).
Does FlightGoggles currently support Stereo?
Yes! Simply pass render_stereo:=true to the FlightGoggles launch file. Note: as of v2.0.2 the combined vertical resolution of the two stereo cameras must not be greater than the vertical resolution of the largest monitor attached to your computer. In other words, you must have a monitor with >=1536 vertical resolution to render stereo at the default camera resolution. A current workaround is to decrease the default camera resolution, attach a high resolution "dummy" monitor, or rotate or attach a vertical display to your rendering computer.
As an explanation for the current restriction, FlightGoggles uses the GPU backbuffer for storing rendered images. However, the size of this buffer is limited by the screen resolution. Thus, concatenated images cannot be larger than the size of the GPU backbuffer. This issue will be patched in a later release.
Is there an easy way to reset the simulation to its intial state without having to restart FlightGoggles?
Yes, you can reset the dynamics by publishing an empty message std_msgs/Empty to the ropic /uav/input/reset, e.g. from a terminal using the command: rostopic pub /uav/input/reset std_msgs/Empty.
Why is the vehicle not moving?
In order to start the dynamics simulation, the vehicle must be armed by publishing an empty message std_msgs/Empty to the ropic /uav/input/arm, e.g. from a terminal using the command: rostopic pub /uav/input/arm std_msgs/Empty.
FlightGoggles crashes on startup or on scene load.
So far, we have seen 2 reasons for crashes on startup:
Insufficient VRAM (< 2.1GB).
Solved by upgrading GPU or switching to AWS rendering.
Vulkan renderer choosing wrong GPU.