2 Commits

Author SHA1 Message Date
Dane Sabo
bc3a6028a9 docs: flag soundness, alpha-drift, saturation-hybrid in file headers
Three caveats surfaced during walkthrough lived only in the
conversation transcript before this commit.  Now they live where
future agents and future-me will actually see them:

- reach_operation.m and reachability/README.md state prominently that
  the current reach tube is an over-approximation of the LINEAR
  model, not a sound tube for the nonlinear plant.  Thesis-blocking
  for a real safety claim.  Upgrade paths documented.

- ctrl_heatup.m header and plant-model/CLAUDE.md note that the
  feedback-linearization u_ff assumes exact alpha_f, alpha_c.  Real
  plants drift (burnup ~20%, boron ~10x, xenon).  Robust treatment =
  parametric reach with alpha as an interval.

- ctrl_heatup.m header and plant-model/CLAUDE.md note that sat() is
  formally a 3-mode piecewise-affine sub-system.  Operation-mode LQR
  is dormant (trivially); heatup will need either a dormancy proof
  or explicit hybrid modeling.

README.md top-level now has a run-commands table for the reach
artifacts and a pointer to the soundness status.

Hacker-Split: raise caveats from transcript to artifact so the work
is actually reviewable by people who weren't in the room.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-17 16:15:39 -04:00
Dane Sabo
d2997c2861 plant-model: add shutdown/heatup/scram controllers and LQR, linearize
Fill out the DRC mode set with ctrl_shutdown (u = -5*beta), ctrl_scram
(u = -8*beta), and ctrl_heatup (feedback-linearizing P on ramped T_avg
reference, saturated u, no integrator). Add ctrl_operation_lqr as a
full-state-feedback counterpart to ctrl_operation — K cached, closed-loop
essentially perfect under the 100%->80% Q_sg step where plain P has ~5F
overshoot.

Add pke_linearize for numerical (A, B, B_w) Jacobians at any operating
point; test_linearize confirms ~4e-4 rel err vs nonlinear sim for a
5% Q_sg step. Extend pke_solver with an optional x0 argument so each
mode can start from a plausible IC.

main_mode_sweep.m exercises all five modes back-to-back and saves the
4-panel plots. CLAUDE.md updated with model-validity-range note (trust
region is ~+/-50C around operating point; true cold shutdown is out of
scope for the linear feedback coefficients).

Hacker-Split: build out control layer end-to-end for reachability.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-17 12:52:03 -04:00