SkyEye: AI Powered GCI Bot for DCS

SkyEye is a Ground Controlled Intercept (GCI) bot for the flight simulator Digital Combat Simulator (DCS). A GCI bot allows players to request information about the airspace in English using either voice commands or text entry, and to receive answers via verbal speech and text messages.

SkyEye uses Speech-To-Text and Text-To-Speech technology which runs locally on the same computer as SkyEye. No cloud APIs are required. It works with any DCS mission, singleplayer or multiplayer. No special scripting or mission editor setup is required. You can run it for less than a nickel per hour on a cloud server, or run it on a PC in your home.

SkyEye is production-ready software! I am currently working on documentation and finalizing the developer API in preparation for the 1.0 release.

Getting Started

• Players: See the user guide for instructions on using the bot.
• Server admins: See the admin guide for a technical guide on deploying the bot.
• Developers: See the contributing guide for instructions on building, running and modifying the bot.
• Please also see the privacy statement to understand how SkyEye uses your voice and gameplay data to function.

Technology

SkyEye would not be possible without these people and projects, for whom I am deeply appreciative:

• DCS-SRS by @ciribob. Ciribob also patiently answered many of my questions on SRS internals and provided helpful debugging tips whenever I ran into a block in the SRS integration.
• Tacview - specifically, ACMI real time telemetry - provides the data feed from DCS World.
• @rurounijones's OverlordBot was a useful reference against SkyEye during early development, and Jones himself was also patient with my questions on Discord.
• @ggerganov's whisper.cpp models provides speech-to-text.
• @rodaine's numwords module is invaluable for parsing numeric quantities from voice input.
• Piper by the Rhasspy voice assistant project is used for speech-to-text.
• The Jenny dataset by Dioco provides the feminine voice for SkyEye.
• @popey's dataset provides the masculine voice for SkyEye.
• @amitybell's embedded Piper module makes distribution and implementation of Piper a breeze. @nabbl improved this module by adding support for macOS and variable speeds.
• The Opus codec and the hraban/opus module provides audio compression for the SRS protocol.
• @hbollon's go-edlib module provides algorithms to help SkyEye understand when it slightly mishears/the user slightly misspeaks a callsign or command over the radio.
• @lithammer's shortuuid module provides a GUID implementation compatible with the SRS protocols.
• @zaf's resample module helps with audio format conversion between Piper and SRS.
• @martinlindhe's unit module provides easy angular, length, speed and frequency unit conversion.
• @paulmach's orb module provides a simple, flexible GIS library for analyzing the geometric relationships between aircraft.
• @proway's go-igrf module implements the International Geomagnetic Reference Field used to correct for magnetic declination.
• Cobra is used for the CLI frontend, including configuration flags, help and examples. Viper is used to load configuration from a file/environment variables.
• MSYS2 provides a Windows build environment.
• @bwmarrin's discordgo module provides the Discord tracing integration.
• @pasztorpisti's go-crc module provides algorithms for negotiating handshakes with TacView telemetry sources.
• Oto was helpful for debugging audio format conversion problems.
• zerolog is helpful for general logging and printf debugging.
• testify is used in unit tests.
• Multiple DCS communities provide invaluable feedback and morale-booster energy:
  • Team Lima Kilo and the Flashpoint Levant community
  • The Hoggit Discord server
  • Digital Controllers
  • 1VSC
  • CVW8
  • @Frosty-nee
• The Ace Combat series by PROJECT ACES/Bandai Namco and Project Wingman by Sector D2 are massive influences on my interest in GCI/AWACS, and aviation in general. This project would not exist without the impact of Ace Combat 04: Shattered Skies.
• And of course, DCS World is produced by Eagle Dynamics.

FAQ

Is this ready?

SkyEye is production ready software. It is used by the Flashpoint Levant public server and multiple private squadrons. A v1.0 release is being prepared for the end of 2024.

What kind of hardware does it require?

See the Hardware section of the admin guide.

Can I train the speech recognition on my voice/accent?

Since the software runs 100% locally, the speech recognition model is a local file. Server operators can provide a trained model as an alternative to the off-the-shelf model. See this blog post for an example.

I don't plan to provide a mechanism for players to submit their voice recordings to the main repository due to data privacy concerns.

Does this use Line-Of-Sight restrictions?

Not at this time. I am working on a solution for this, but it will take me a while.

If this is a critical feature for you, consider using MOOSE's AWACS module instead. It supports Line-Of-Sight and datalink simulation, at the tradeoff of requiring some special setup in the Mission Editor.

OverlordBot also optionally supports this feature, although less than 1% of users used it.

Will this work with DCS' built-in VoIP?

Hopefully in the future Eagle Dynamics will add support for external GCI bots. If anyone at ED is reading this, access to any relevant preview builds would be really helpful!

Could this use a Large Language Model? (llama, mistral, etc.)

This deserves a longer answer, for now see this issue

TL;DR most of the controller logic is simple geometry that completes in about a millisecond. An LLM is several orders of magnitude slower, less accurate and a more difficult user experience.

We use AI for the "squishy" problems - understanding human speech, and synthesizing human-like speech. We use traditional code for the algorithmic problems.

Could this provide ATC services?

This deserves a longer answer, for now see this issue

TL;DR I have no plans to attempt an ATC bot.

Can you add an option to do insert feature here?

I'm happy to hear your ideas, but I am very selective about what I choose to implement.

I develop SkyEye at no monetary cost to the user; therefore, one of my priorities is to keep the complexity of the software close to the minimum necessary level to ease the maintenance burden. I'm focusing only on features that are useful to most players. I avoid adding features that are gated by configuration options, because each one multiplies the permutations that need to be tested and debugged. See this video.

When is SkyEye's birthday?

October 12th. At some point I'll put an Ace Combat 04 easter egg in there.