This project implements a simplified but realistic Air Traffic Control (ATC) system built in C++ and designed to run on the QNX real-time operating system.
The system simulates aircraft, radar updates, operator commands, and collision-risk detection using multi-process communication and periodic real-time updates.

The system models the core responsibilities of an ATC center:

• Tracking aircraft positions in real time
• Exchanging messages between multiple processes (radar, aircraft, operator console)
• Predicting potential conflicts based on velocity vectors
• Logging system status and collision warnings
• Responding to operator commands (speed, altitude, position, prediction window)

• Maintains the shared, real-time state of all aircraft
• Receives radar updates and operator commands
• Stores aircraft objects in memory
• Triggers collision detection at regular intervals
• Logs system events and aircraft lists

• Periodically calculates updated aircraft positions
• Sends updates to the ComputerSystem
• Simulates real radar sweeps using timers

• One process per aircraft
• Stores speed, altitude, heading, and position
• Responds to operator commands routed through CommSystem

• Allows the operator to:
  • Select an aircraft
  • Change altitude, speed, or heading
  • Modify the conflict prediction time window
• Sends commands through the CommSystem server

• Central message-routing server
• Receives operator commands
• Delivers them to the target aircraft process
• Isolates communication logic from core ATC logic

• Prints:
  • Aircraft lists
  • System logs
  • Collision warnings (“WARNING”, “IMMINENT”)
• Updated periodically by the ComputerSystem

The system includes a predictive collision-risk algorithm:

• Uses aircraft positions and velocity vectors
• Computes predicted separation over a configurable horizon
• Default window: 180 seconds
• Produces:
  • WARNING alerts
  • IMMINENT alerts
• Logs each detection event with timestamps

• MsgSend() / MsgReceive() for process-to-process commands
• Pulses and timers for periodic updates
• Mutex-protected shared data
• Channel-based message routing

Air-Traffic-Control/
├── src/
├── Aircraft/
└── build/

• QNX SDP
• QCC or GCC toolchain

make

./build/atc

• Stable under increasing aircraft load
• Real-time updates maintained
• Constraints approached at ~60 aircrafts

• Mamadou Kaba
• Maïka Trépanier
• Lifu Zhang