Project Helga's flight computer runs a purpose-built real-time operating system written entirely in C++ from the avionics bus up — no third-party flight stack, no licensed black-box firmware. Every embedded system on the vehicle is documented, versioned, and published as part of Overby's open-source engineering commitment.
Three independent flight computers run the same real-time control loop in lockstep, each reading the same sensor bus and voting on actuator commands before any command reaches a control surface, thruster, or propulsion subsystem. A disagreement between any one computer and the other two is resolved by majority vote and logged for post-flight review — the outvoted unit is isolated but never physically shut down mid-flight.
The control loop itself runs at a fixed 1kHz cycle rate across every flight phase — atmospheric cruise, orbital insertion, reentry, and runway approach — with no mode switch that could introduce a timing discontinuity at the worst possible moment.
Overby Industries publishes avionics architecture, sensor fusion algorithms, and control loop design through accessible public repositories — treating flight software transparency as foundational to long-term institutional trust, not a competitive liability.
Inertial, GPS/GNSS, air data, and star-tracker inputs are fused in a custom Kalman filter implementation tuned specifically for the transition between atmospheric and orbital flight regimes.
Trajectory planning and guidance run as a deterministic C++ module with no dynamic memory allocation in the hot path — every timing behaviour is provable ahead of flight, not just tested.
The flight computer detects sensor and actuator faults in real time and reconfigures control authority around the failure without ground intervention, critical for phases where light-lag or signal blackout rules out real-time human input.
Full state telemetry is logged onboard and streamed to ground whenever link is available, giving engineers complete post-flight visibility into every control decision the vehicle made.