e69fd0a6f4
predicates.json is the single source of truth for concretizing the
FRET-spec predicates (t_avg_above_min, t_avg_in_range, p_above_crit,
inv1_holds, inv2_holds) as polytopes {x : A x <= b}. Until now these
were abstract booleans in the synthesis spec; reach analysis
re-invented ad-hoc thresholds that weren't tied to the spec. Closes
the Thrust-1-meets-Thrust-3 seam.
T_standby now defined as T_c0 - 60 F = 275 C (from user review).
Replaces the earlier simplification where shutdown IC held all temps
at T_cold0. 275 C is inside the model's +/-50 C trust region around
operating point and above coolant saturation at reduced pressure.
load_predicates.m in MATLAB reads the JSON and resolves rhs_expr
strings (which reference plant-derived constants like T_c0, T_cold0,
T_standby) into numeric bounds. Returns per-predicate (A_poly, b_poly)
plus a constants struct.
main_mode_sweep.m now pulls T_standby from predicates and uses it
for shutdown + heatup ICs. Heatup horizon extended to 90 min to
cover the wider 60 F -> operating range at 28 C/hr tech-spec limit.
reach_operation.m reads delta_safe_Tc from the t_avg_in_range
halfspace instead of hardcoding +/-5 K. Current concretization is
+/-2.78 C (~5 F); LQR reach still shows 28x margin.
inv1_holds and inv2_holds are marked PLACEHOLDER in the JSON —
engineering best guesses, not derived from a specific plant's tech
specs or a DNBR correlation. Revisit before thesis defense.
Hacker-Split: single-source concretization for FRET predicates,
end seam with reach.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
pwr-hybrid-3-demo
Preliminary example for the HAHACS thesis — a verified hybrid controller for a small modular PWR startup. Composes three layers into one demonstrable pipeline:
- Discrete layer (
fret-pipeline/): FRET natural-language requirements → LTL → synthesized AIGER controller → state-machine diagram. - Continuous layer (
plant-model/): 10-state point kinetic equation + thermal-hydraulics PWR model with bounded steam-generator heat removal as the disturbance input. - Research context (
thesis/): the HAHACS PhD proposal that motivates and formalizes the methodology.
Layout
pwr-hybrid-3-demo/
CLAUDE.md AI-facing context and architecture map
docs/
architecture.md How the discrete and continuous layers compose
figures/ Shared figures for thesis + talks
fret-pipeline/ FRET → ltlsynt → AIGER → state machine
plant-model/ PWR point kinetics + thermal-hydraulics
reachability/ Continuous-mode verification (linear-model tube + Lyapunov barrier attempt; see README)
julia-port/ Parallel plant-model port + ReachabilityAnalysis.jl scaffold
hardware/ Ovation HIL artifacts (TBD)
claude_memory/ Session notes by AI agents (distilled up into CLAUDE.md over time)
thesis/ [submodule] PhD proposal
presentations/
2026DICE/ [submodule] DICE 2026 abstract
Quickstart
Clone with submodules:
git clone --recurse-submodules <url>
cd pwr-hybrid-3-demo
Run the controller synthesis pipeline:
cd fret-pipeline
python3 scripts/fret_to_synth.py pwr_hybrid_3.json specs/synthesis_config_v3.json
bash scripts/synthesize.sh specs/synthesis_config_v3.json circuits
python3 scripts/trace_aiger.py circuits/PWR_HYBRID_3_DRC.aag diagrams
dot -Tpng diagrams/PWR_HYBRID_3_DRC_states.dot -o diagrams/PWR_HYBRID_3_DRC_states.png
Run the plant model (MATLAB in plant-model/ — Octave compatibility not tested since the LQR pieces landed):
main % original single-scenario demo (null vs operation)
main_mode_sweep % all five DRC modes back-to-back, writes to ../docs/figures/
test_linearize % Jacobian sanity check, saves linearization for reach
Run the reach artifacts (reachability/):
reach_operation % linear reach tube for operation-mode LQR
barrier_lyapunov % Lyapunov-ellipsoid barrier cert attempt (sweeps weights)
Soundness note: the current reach tube is the LINEAR model's tube;
it is not yet a sound over-approximation of the nonlinear plant. See
reachability/README.md § Soundness status.
Prerequisites
- Python 3.10+
- Spot for
ltlsynt(brew install spot) - Graphviz for
dot(brew install graphviz) - MATLAB or GNU Octave for the plant model
- LaTeX (via
latexmk) for the thesis submodule
Further reading
CLAUDE.md— orientation for AI agents working in this repodocs/architecture.md— how the layers composethesis/CLAUDE.md— the thesis project structurefret-pipeline/README.md— FRET naming conventions and pipeline detailsplant-model/README.md— scenario setup and model equations