The Aerospace Toolbox interface to the FlightGear flight simulator enables you to visualize flight data in a three-dimensional environment. The third-party FlightGear simulator is an open source software package available through a GNU® General Public License (GPL). This section describes how to obtain and install the third-party FlightGear flight simulator. It also describes how to play back 3-D flight data by using a FlightGear example, provided with your Aerospace Toolbox software.
The FlightGear flight simulator interface included with the Aerospace Toolbox product is a unidirectional transmission link from the MATLAB® software to FlightGear. It uses FlightGear's published
net_fdm
binary data exchange protocol. Data is transmitted via UDP
network packets to a running instance of FlightGear. The toolbox supports multiple standard
binary distributions of FlightGear. For interface details, see Flight Simulator Interface Example
following.
FlightGear is a separate software entity that is not created, owned, or maintained by MathWorks.
To report bugs in or request enhancements to the Aerospace Toolbox FlightGear interface, contact MathWorks technical support at https://www.mathworks.com/support/.
To report bugs or request enhancements to FlightGear itself, go to www.flightgear.org
and use
the contact page.
The Aerospace Toolbox product supports FlightGear versions starting from v2.6.
You can obtain FlightGear software from www.flightgear.org
in the
download area or by ordering CDs from FlightGear. The download area contains extensive
documentation for installation and configuration. Because FlightGear is an open source
project, source downloads are also available for customization and porting to custom
environments.
You must have a high-performance graphics card with stable drivers to use FlightGear.
For more information, see the FlightGear CD distribution or the hardware requirements and
documentation areas of the FlightGear website, www.flightgear.org
.
FlightGear distributions are available for Linux®, Mac OS X, and other UNIX® platforms from the FlightGear website, www.flightgear.org
.
Installation on these platforms, like Windows®, requires careful configuration of graphics cards and drivers. Consult the
documentation and hardware requirements sections at the FlightGear website.
Your computer built-in video card, such as NVIDIA® cards, can have issues working with FlightGear shaders. Consider this workaround:
Disable the FlightGear shaders by specifying the DisableShaders
property of the Aero.FlightGearAnimation
object to the GenerateRunScript (Aero.FlightGearAnimation)
method.
The extensive FlightGear documentation guides you through the installation. For complete
installation instructions, consult the documentation section of the FlightGear website
www.flightgear.org
.
Note:
Generous central processor speed, system and video RAM, and virtual memory are essential for good flight simulator performance.
For more information, see http://wiki.flightgear.org/Hardware_recommendations
.
Have sufficient disk space for the FlightGear download and installation.
Before you install FlightGear, configure your computer graphics card. See the preceding section, Configuring Your Computer for FlightGear.
Before installing FlightGear, shut down all running applications (including the MATLAB software).
Install FlightGear in a folder path name composed of ASCII characters.
The operational stability of FlightGear is especially sensitive during startup. It is best to not move, resize, mouse over, overlap, or cover up the FlightGear window until the initial simulation scene appears after the startup splash screen fades out.
The current releases of FlightGear are optimized for flight visualization at altitudes below 100,000 feet. FlightGear does not work well or at all with very high altitude and orbital views.
The Aerospace Toolbox product supports FlightGear on a number of platforms (System Requirements). The following table lists the properties to be aware of before you start using FlightGear.
FlightGear Property | Folder Description | Platforms | Typical Location |
---|---|---|---|
| FlightGear installation folder. | Windows |
|
Linux | Directory into which you installed FlightGear | ||
Mac |
| ||
| Model geometry folder | Windows |
|
Linux |
| ||
Mac |
|
When you install the FlightGear software, the installation provides a basic level of scenery files. The FlightGear documentation guides you through installing scenery as part the general FlightGear installation.
If you need to install more FlightGear scenery files, see the instructions at
http://www.flightgear.org
. Those instructions describe how to install
the additional scenery in a default location.
If you install additional scenery in a non-standard location, you may need to update the
FG_SCENERY
environment variable in the script output from the GenerateRunScript
function to include the new
path. For a description of the FG_SCENERY
variable, see the documentation
at http://www.flightgear.org
.
If you do not download scenery in advance, you can direct FlightGear to download it
automatically during simulation using the InstallScenery
property of the
Aero.FlightGearAnimation
object for the GenerateRunScript (Aero.FlightGearAnimation)
method.
For Windows systems, you may encounter an error message while launching FlightGear with
the InstallScenery
option enabled:
Error creating directory: No such file or directory
This error likely indicates that your default FlightGear download folder is not
writeable, the path cannot be resolved, or the path contains UNC path names. To work around
the issue, edit the runfg.bat
file to specify a new folder path to store
the scenery data:
Edit runfg.bat
.
To the list of command options, append --download-dir=
and
specify a folder to which to download the scenery data. For example:
--download-dir=C:\Users\user1\Documents\FlightGear
All data downloaded during this FlightGear session is saved to the specified directory. To avoid downloading duplicate scenery data, use the same directory in succeeding FlightGear sessions
To open FlightGear, run runfg.bat
.
Note
Each time that you run the GenerateRunScript
function, it creates a new
script. It overwrites any edits that you have added.
The Aerospace Toolbox product provides an example named Displaying Flight Trajectory Data. This example shows you how you can visualize flight trajectories with FlightGear Animation object. The example is intended to be modified depending on the particulars of your FlightGear installation. Use this example to play back your own 3-D flight data with FlightGear.
Before attempting to simulate this model, you must have FlightGear installed and configured. See About the FlightGear Interface.
To run the example:
Import the aircraft geometry into FlightGear.
Run the example. The example performs the following steps:
Loads recorded trajectory data.
Creates a time series object from trajectory data.
Creates a FlightGearAnimation object.
Modify the animation object properties, if needed.
Create a run script for launching the FlightGear flight simulator.
Start the FlightGear flight simulator.
Play back the flight trajectory.
Before running the example, copy the aircraft geometry model into FlightGear. From the following procedures, choose the one appropriate for your platform. This section assumes that you have read Install and Start FlightGear.
If your platform is Windows:
Go to your installed FlightGear folder. Open the
data
folder, and then the Aircraft
folder:
.FlightGear
\data\Aircraft\
If you have previously run the Aerospace Blockset™ NASA HL-20 with FlightGear Interface example, you might already have an
HL20
subfolder there.
Otherwise, copy the HL20
folder from the
matlabroot
\toolbox\aero\astdemos\
folder to the FlightGear
\data\Aircraft\
folder. This folder contains the preconfigured geometries for the HL-20 simulation and
HL20-set.xml
. The file
matlabroot
\toolbox\aero\aerodemos\HL20\models\HL20.xml
defines the geometry.
If your platform is Linux:
Go to your installed FlightGear folder. Open the
data
folder, then the Aircraft
folder:
.$FlightGearBaseDirectory
/data/Aircraft/
If you have previously run the Aerospace Blockset NASA HL-20 with FlightGear Interface example, you might already have an
HL20
subfolder there. If that is the case, you do not have to do
anything, because you can use the existing geometry model.
Otherwise, copy the HL20
folder from the
matlabroot
/toolbox/aero/aerodemos/
folder to the
$FlightGearBaseDirectory
/data/Aircraft/
folder. This folder contains the preconfigured geometries for the HL-20 simulation and
HL20-set.xml
. The file
matlabroot
/toolbox/aero/aerodemos/HL20/models/HL20.xml
defines the geometry.
If your platform is Mac:
Open a terminal.
List the contents of the Aircraft folder. For example, type:
ls $FlightGearBaseDirectory/data/Aircraft/
If you have previously run the Aerospace Blockset NASA HL-20 with FlightGear Interface example, you might already have
an HL20
subfolder there. In this case, you do not have to do
anything, because you can use the existing geometry model. Continue to Running the Example.
Otherwise, copy the HL20
folder from the
matlabroot/toolbox/aero/aerodemos/
$FlightGearBaseDirectory/FlightGear.app/Contents/Resources/data/Aircraft/
HL20-set.xml
. The file
matlabroot
/toolbox/aero/aerodemos/HL20/models/HL20.xml
defines the geometry.
Start the MATLAB software.
Enter astfganim
in the MATLAB Command Window.
While running, the example performs several steps by issuing a series of commands.