last_theta_ist was hardcoded to 20 in __init__, used to compute the very
first process() tick's heatrate as (theta_ist - 20)/dt*60 - a wildly bogus
spike whenever the real starting temperature wasn't actually 20 (e.g.
1200 deg/min for a 40-degree start). The exponentially-smoothed
heatrate_ist (alpha=0.1) takes several ticks to recover from that, during
which it distorts the PID's rate-error term and visibly throws off the
heating trajectory.
This was invisible everywhere this assumption was implicitly tested,
since ambient (and every start_theta used) was always exactly 20. It
surfaced once SudForecastEstimator.estimate() started being called with a
real, non-20 start_theta: it builds a fresh TempController on every call,
so its first tick always hits this bug fresh - unlike the real controller,
which only ever goes through this once near server startup and has long
since self-corrected (last_theta_ist = theta_ist runs every tick) by the
time any forecast comparison matters. That's exactly what showed up as a
forecast-vs-actual gap during the initial ramp.
last_theta_ist now starts None; process() treats the first tick's
heatrate as 0 (no real history yet) instead of computing it against a
hardcoded, usually-wrong baseline.
Verified: ambient=20 (the only case ever exercised before) is byte-
identical to before the fix. ambient=40/start=40 - reproducing the old
hardcoded-20 behavior side by side - shows the old version visibly lagging
~12 minutes behind the fixed one during the initial ramp before they
converge, matching the reported gap exactly.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DkkuG48uHFCGKe6dPSERFk
TempController(Smith).__init__ no longer takes model_params/theta_amb -
set_model_plant_params() and the existing set_ambient_temperature() must be
called instead (mirrors components/plant/pot.py's own Pot constructor
refactor). temp_controller.py's now-pointless model_params/theta_amb
constructor placeholders (kept only for "compatibility" with Smith) are
dropped too.
Both TempController variants now raise a clear RuntimeError from process()
itself if set_params() wasn't called, instead of letting it surface deep
inside Pid.process() as an opaque "'NoneType' object is not subscriptable".
Smith additionally checks its internal models via Pot.is_configured() (new)
and raises if set_model_plant_params()/set_ambient_temperature() weren't
called either.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DkkuG48uHFCGKe6dPSERFk
Mirrors components/pid/pid.py's own Pid.set_params() pattern: params/
thresholds start out None, and set_params() configures pid_hold/pid_heat/
pid_cool from them. process()/process_fsm() fail naturally (TypeError on
None) if called before set_params() - same as Pid.process() already does -
rather than a new bespoke check. Updates all callers (server/brewpi.py,
SudForecastEstimator, and the pid/sud demo scripts) to call set_params()
right after construction.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DkkuG48uHFCGKe6dPSERFk
PidFactory.create() calls both controllers with the same (dt, params,
model_params, theta_amb=...) signature, but TempController ("Normal")
only accepted (dt, params) - any config using pid_type "Normal" would
crash with a TypeError on startup. It has no internal model, so just
accepts and ignores the extra arguments.
Pid.scale(k) set self.k as persistent state, mutated from outside the
class and never reset in reset(), so a stale scale factor could survive
a state-transition reset. Replace it with a plain scale=1.0 argument on
Pid.process(), and have temp_controller.py/temp_controller_smith.py
compute the heat-rate-overshoot compensation factor themselves and pass
it through process_pid() each tick instead of mutating pid_hold's state.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
[Sensor] - replace TempSensorSim's hardcoded k_noise with configurable
temp_offset/variance, accept **kwargs on Max31865 too so both sensors
share a constructor signature usable from TempSensorFactory.create()
[Temp Controller] - low-pass filter the backward-difference heat-rate
estimate (alpha=0.1) in both temp_controller.py and
temp_controller_smith.py instead of using the raw, noisy derivative
[Pot] - drop kn from demo_pot.py's params, matching the unused-field
removal already made to pot.py itself
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
temp_controller.py, temp_controller_smith.py, and kalman.py imported
matplotlib at module level just to support eyeballed-plot __main__
blocks, coupling the live server's import graph to a GUI plotting lib
it never uses at runtime. Relocate those demos (and kalman_eval.py) to
scripts/demos/pid/ and strip the now-unused imports/__main__ blocks
from the production files.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
TempControllerBase no longer threads model_params through (only the
Smith subclass needs it, for its own Pot model and Kalman filters).
Enable the Smith predictor's actual delay-compensated error term
(theta_err now uses theta_ist_plant - theta_ist_model_delay +
theta_ist_model instead of the plain plant reading), which is the
correction this controller is named for.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Both controllers had nearly identical process_fsm(), process_pid(),
and all getters/setters; only Kalman/model setup and process()
genuinely differed, and the duplication had already drifted (the
Smith variant resets model state on entering HEAT, the plain one
didn't).
Add TempControllerBase with the shared logic and three small hooks
(init_kalman, on_state_entered, post_pid) subclasses use to plug in
their own Kalman/model behavior. Each subclass now contains only what
makes it different.
Also fixes a latent crash: TempController's constructor only accepted
(dt, params), but PidFactory/brewpi.py always call it with a third
model_params arg, so pid_type "Normal" would have raised TypeError.
The shared base's model_params=None default fixes this. Also
initializes the Smith controller's trace attributes in __init__
instead of leaving them undefined until the first process() call.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
jensandClaude Sonnet 4.6
jens