Flying the Virtual Drone with Code

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This page assumes you’ve followed the steps in Environment Setup (Windows) or Environment Setup (Linux).

Table of Contents

During Development (Unreal Editor and running code manually)

Configuring the Environment

Ensure that your AirSim settings are up to date using the ./update_airsim_settings.ps1 command located in the root of the SUAS repository. The essence of this script is copying a file to where AirSim expects a settings.json file. We have a few pre-made templates available, but you can refer to the Project AirSim Settings Documenation or AirSim Settings Documentation for more details.

Single-Drone

Flying a single drone is easiest. For a quick start, you can run the following command from the SUAS repository root to set up your settings:

.\update_airsim_settings.ps1 .\templates\airsim-settigns-ardupilot.json

If you have a custom settings file:

.\update_airsim_settings.ps1 .\path\to\your\settings.json

Multi-Drone Settings

If you wish to fly multiple drones, that must be reflected in your settings. Manually doing this is tedious, so our script provides functionality to automate this. For a quick start with 4 drones, you can use the following:

.\update_airsim_settings.ps1 .\templates\airsim-settings-multidrone.json -NumDrones 2,2

The number of drones is given as a grid (rows,columns), so the total number of drones is rows * columns.

It is important to note that the file provided to the script is used as a reference by which a new settigns file is generated. The global settings of the reference is copied as is; the vehicle provided in the reference’s "Vehicles" section is used as a base for the generated vehicle entries. All settings within the reference vehicle are copied verbatim except for the ports and X, Y, and Z offsets. The port are incremented by 10 from the reference droens for each drone, and the X, Y, and Z are set based on command arguments (which default to 3-meter separation).

For instance, given this reference vehicle:

{
    "VehicleType": "ArduCopter",
    "UseSerial": false,
    "LocalHostIp": "127.0.0.1",
    "UdpIp": "127.0.0.1",
    "UdpPort": 9003,
    "ControlPort": 9002
}

The following drones will be generated:

{
    "VehicleType": "ArduCopter",
    "UseSerial": false,
    "LocalHostIp": "127.0.0.1",
    "UdpIp": "127.0.0.1",
    "UdpPort": 9003,
    "ControlPort": 9002,
    "X": 0, "Y": 0, "Z": -1
},
{
    "VehicleType": "ArduCopter",
    "UseSerial": false,
    "LocalHostIp": "127.0.0.1",
    "UdpIp": "127.0.0.1",
    "UdpPort": 9013,
    "ControlPort": 9012,
    "X": 3, "Y": 0, "Z": -1
},
{
    "VehicleType": "ArduCopter",
    "UseSerial": false,
    "LocalHostIp": "127.0.0.1",
    "UdpIp": "127.0.0.1",
    "UdpPort": 9023,
    "ControlPort": 9022,
    "X": 0, "Y": 3, "Z": -1
},
{
    "VehicleType": "ArduCopter",
    "UseSerial": false,
    "LocalHostIp": "127.0.0.1",
    "UdpIp": "127.0.0.1",
    "UdpPort": 9033,
    "ControlPort": 9032,
    "X": 3, "Y": 3, "Z": -1
}

Any camera settings and such will be carried over for all drones.

More on .\update_airsim_settings.ps1

Parameters:

Flying

  1. Open your AirSim Unreal Engine project
    • you can run AirSim’s default project, called Blocks, located in your AirSim folder at \AirSim\Unreal\Environments\Blocks\Blocks.uproject
      • open the uproject directly in Unreal; trying to run blocks from the Visual Studio Solution probably won’t work
      • if it says that the project was built with a different Unreal version, click “Yes” to rebuild with the version you have
  2. Open a terminal and navigate to the root of the SUAS repository
    • start WSL using the wsl command as well
  3. Start the Unreal Engine simulation using the editor’s Play button
    • located above the viewport to the far right
    • if not immediately visible, press the double-arrow ($>!!>$) button, then Play
    • the Unreal Editor should freeze (this is normal)
  4. Start the sim and env containers using ./run_container.sh
    • for multi-drone, you must specify the number of drones using the NUM_DRONES environment variable: NUM_DRONES=4 ./run_container.sh
      • you only need to provide the environment variable when running a command that starts the sim container
  5. run your code:
    • if using the env container, attach to the env container: ./run_container.sh attach env
    • run your code now

Whenever you want to rerun code, you must

Production

The final rendition of the simulation is a work in progress! Use the developer stuff for now.