Selected engineering scope
GNC Subsystem Prototyping
Prototype guidance, navigation, and control with explicit autonomy boundaries and HIL hooks - before simulation confidence becomes vehicle risk.
System path
SenseTimed, imperfect measurements entering the control loop.
- Domains
- GNC · Unmanned · Autonomy
- Maturity
- TRL 2-5 prototyping band
01 · Problem
Context & challenge
Prototype GNC behavior while keeping the autonomy boundary, telemetry needs, and HIL validation path explicit from the start.
GNC prototypes often optimize for algorithmic elegance in simulation. The first collision with reality is usually timing jitter, sensor bias, actuator delay, or an unclear decision about what must run onboard.
Without an explicit autonomy boundary, teams discover too late that "the algorithm" depended on offboard compute, perfect state, or telemetry that will not exist in flight.
This selected engineering scope emphasizes prototyping that is honest about interfaces: sense, compute, decide, and validate as a closed loop with HIL hooks from the outset.
02 · Approach
How the work was structured
- 01
Draw the autonomy boundary early
Decide what must run onboard under degraded links, what may stay offboard in prototype phases, and how that boundary will migrate as maturity increases.
- 02
Prototype against interface reality
Prefer early contact with representative sensors, timing, and actuator models over polishing controllers against idealized state.
- 03
Instrument the decision loop
Telemetry should expose enough control state for diagnosis - not only vehicle pose for operators. Debugging GNC without observability is archaeology.
- 04
Make HIL a first-class environment
Design hooks so hardware-in-the-loop can exercise sense/decide/act paths before vehicle-level testing becomes the only option.
03 · System
Layer walkthrough
Sense → Compute → Decide → Validate
Sense
Sensor inputs treated as noisy, timed signals with explicit assumptions - not perfect truth injected into the controller.
Compute
Onboard compute budgets and scheduling constraints shape which algorithms are admissible in the prototype path.
Decide
Control and guidance decisions bounded by the autonomy contract: what the vehicle may do without continuous external authority.
Validate
HIL and controlled environments used to retire interface risk before expanding to full vehicle dynamics.
04 · Tradeoffs
Constraints & tradeoffs
Simulation fidelity vs. schedule
High-fidelity simulation is valuable, but it cannot replace interface validation. Balance model depth with early hardware contact.
Autonomy creep
Prototype features often quietly expand the autonomy boundary. Capture the boundary in writing so expansion is intentional.
Telemetry bandwidth
Control diagnostics compete with payload and ops data. Prioritize what is required to verify the loop.
05 · Outcomes
Validation & result categories
Outcome wording describes engineering progress categories - not quantified performance claims or named deployments.
- Prototype validated in controlled environments
- HIL workflow introduced
- Autonomy boundary definitions captured
- Integration risk reduced before vehicle-level work
- Autonomy boundary documented for onboard vs offboard responsibilities.
- Prototype exercised with interface-aware stimuli rather than idealized state alone.
- HIL hooks established for subsequent control-loop validation.
Technologies
- GNC algorithms
- ROS / ROS2
- HIL
- Telemetry
ConfidentialityIllustrative capability description. No performance claims or program names.
Next step
Facing a related integration or architecture problem?
A focused technical discussion covering mission context, constraints, highest-risk unknowns, and a practical next engineering step.