Files
forgefirm/scripts/bench/flow_warm_validate.py
T
ScottW514 ff117c4f6b bench: reach the board through a configurable ssh client; document every tool
The host-side coolant and fan tools call the ssh on PATH, or the client
named by GF_SSH (a wrapper such as a WSL distro's ssh), instead of a
fixed wrapper. The bench README lists every committed tool and data
file, and explains how the coolant-flow fire-gate threshold was
derived from the committed flow-matrix data and how to re-run that
derivation on another machine.
2026-08-15 06:12:39 -04:00

211 lines
7.5 KiB
Python

#!/usr/bin/env python3
"""Validate the flow check at a WARM loop baseline - the condition a
real job actually presents.
Every design-matrix run started near ambient (21-23 C). During a cut the
loop sits warmer, where heat loss to ambient is larger, which shrinks
the measured rise in BOTH the flow and no-flow cases and could compress
the margin the threshold depends on. This warms the loop with its own
heater (which plateaus near 28-29 C - the most it can reach unaided),
then runs the real check at 40% / 50 s with the cut-profile fans, and
alternates flow / no-flow so both cases see the same conditions.
Usage: flow_warm_validate.py [cycles_per_case] (default 3)
"""
import json
import math
import os
import shlex
import statistics
import subprocess
import sys
import time
HOST = os.environ.get('GF_HOST')
if not HOST:
raise SystemExit('set GF_HOST to the machine IP address')
# ssh client used to reach the board; override for a wrapper, e.g.
# GF_SSH='wsl -d <distro> -- ssh'.
SSH = shlex.split(os.environ.get('GF_SSH', 'ssh'))
HERE = os.path.dirname(os.path.abspath(__file__))
RESULTS = os.path.join(HERE, 'flow_warm_results.json')
F = 1024.0 * 1.3
RD, BETA = 10000.0, 3380.0
RINF = 10000.0 * math.exp(-3380.0 / 298.15)
DUTY = 40
CHECK_S = 50
THRESHOLD = 13.7
WARM_TARGET_C = 25.5 # what a ~19-20 C room permits at 50% duty
WARM_MAX_S = 780
ABORT_C = 48.0
FANS_RUN = ('echo 65535 > /sys/glowforge/thermal/exhaust_pwm; '
'echo 43278 > /sys/glowforge/thermal/intake_pwm')
FANS_OFF = ('echo 0 > /sys/glowforge/thermal/exhaust_pwm; '
'echo 0 > /sys/glowforge/thermal/intake_pwm')
def degc(raw):
raw = float(raw)
if raw <= 1.0 or raw >= F:
return float('nan')
r = RD / (F / raw - 1.0)
return BETA / math.log(r / RINF) - 273.15
def board(cmd, timeout=120):
r = subprocess.run(SSH + ['-o', 'PreferredAuthentications=none',
'root@' + HOST, cmd],
capture_output=True, text=True, timeout=timeout)
return r.stdout
_last_good = (22.0, 22.0)
def temps():
"""Sanity-guarded read. A single glitched sysfs value used to map to
~109 C and trip the safety abort, silently ending the warm phase
after one iteration - which wasted two whole validation runs."""
global _last_good
o = board('cat /sys/glowforge/pic/water_temp_1 /sys/glowforge/pic/water_temp_2').split()
if len(o) != 2:
return _last_good
d, u = degc(o[0]), degc(o[1])
if any(x != x or x < 5.0 or x > 60.0 for x in (d, u)):
return _last_good
_last_good = (d, u)
return d, u
def heater(pct):
board('echo %d > /sys/glowforge/thermal/heater_pwm' % int(65535 * pct / 100))
def pump(on):
board('echo %d > /sys/glowforge/thermal/water_pump_on' % (1 if on else 0))
def warm_to(target, log):
"""Warm with the loop heater, pump circulating, fans off."""
pump(True)
board(FANS_OFF)
# 50% is the practical ceiling: the downstream sensor sits AT the
# heater element, so 100% drives it past 50 C within 30 s while the
# bulk has barely moved. At 50% it plateaus near 41 C, leaving the
# bulk free to climb for as long as we let it.
heater(50)
t0 = time.time()
# Plateau detection compares against the reading two minutes back:
# with the pump circulating, the bulk climbs only ~0.5-0.8 C/min, so
# a per-sample threshold mistakes normal warming for a plateau (it
# did exactly that on the first attempt and the whole run executed
# at ambient).
hist = []
while time.time() - t0 < WARM_MAX_S:
d, u = temps()
el = (time.time() - t0) / 60
if u >= target:
log(' warm target reached: up=%.2f at %.1f min' % (u, el))
break
if d >= ABORT_C:
log(' warm abort: downstream %.2f at %.1f min' % (d, el))
break
hist.append(u)
if len(hist) % 4 == 0:
log(' warming: %.1f min down=%.2f up=%.2f' % (el, d, u))
if len(hist) > 8 and u - hist[-9] < 0.3:
log(' (warming plateaued at %.2f C after %.1f min)' % (u, el))
break
time.sleep(15)
heater(0)
pump(True)
time.sleep(45) # mix so the bulk is uniform before measuring
d, u = temps()
log(' warmed to down=%.2f up=%.2f in %.1f min' % (d, u, (time.time() - t0) / 60))
return u
def check(flow, log):
"""The real check: fans at cut profile, 40% heater, 50 s."""
board(FANS_RUN)
pump(flow)
time.sleep(3)
d0, u0 = temps()
heater(DUTY)
raw = board('python3 /data/flow_sampler.py %d 1.0' % CHECK_S, timeout=CHECK_S + 60)
heater(0)
pump(True)
series = []
for line in raw.strip().splitlines():
try:
el, r1, r2 = line.split(',')
series.append((float(el), degc(r1), degc(r2)))
except ValueError:
continue
if not series:
return None
el, d, u = series[-1]
return {'flow': flow, 'base_up': u0, 'base_down': d0, 'down_rise': d - d0,
'up_rise': u - u0, 'peak_down': max(s[1] for s in series), 't': el}
def main():
cycles = int(sys.argv[1]) if len(sys.argv) > 1 else 3
logf = open(os.path.join(HERE, 'flow_warm_log.txt'), 'a')
def log(msg):
print(msg, flush=True)
logf.write(msg + '\n')
logf.flush()
log('=== warm-baseline validation %s duty=%d%% window=%ds threshold=%.1f'
% (time.strftime('%Y-%m-%d %H:%M:%S'), DUTY, CHECK_S, THRESHOLD))
board('pkill -x grblHAL_glowfor; sleep 1; true')
runs = []
try:
for c in range(cycles):
for flow in (True, False):
log(' cycle %d/%d %s' % (c + 1, cycles, 'FLOW' if flow else 'NO-FLOW'))
warm_to(WARM_TARGET_C, log)
r = check(flow, log)
if r:
r['cycle'] = c
runs.append(r)
verdict = 'FAULT' if r['down_rise'] > THRESHOLD else 'ok'
correct = (verdict == 'FAULT') == (not flow)
log(' base_up=%.2f down_rise=%.2f -> %-5s %s (peak down %.1f C)'
% (r['base_up'], r['down_rise'], verdict,
'CORRECT' if correct else '*** WRONG ***', r['peak_down']))
json.dump(runs, open(RESULTS, 'w'), indent=1)
finally:
heater(0)
pump(True)
board(FANS_OFF)
fv = [r['down_rise'] for r in runs if r['flow']]
nv = [r['down_rise'] for r in runs if not r['flow']]
log('')
log('=== warm-baseline results (baselines %.1f - %.1f C)'
% (min(r['base_up'] for r in runs), max(r['base_up'] for r in runs)))
if len(fv) >= 2 and len(nv) >= 2:
log(' flow n=%d mean %.2f sd %.2f max %.2f' % (len(fv), statistics.mean(fv), statistics.stdev(fv), max(fv)))
log(' no-flow n=%d mean %.2f sd %.2f min %.2f' % (len(nv), statistics.mean(nv), statistics.stdev(nv), min(nv)))
log(' worst-case margin: %+.2f C threshold %.1f sits %+.2f above flow max, %+.2f below no-flow min'
% (min(nv) - max(fv), THRESHOLD, THRESHOLD - max(fv), min(nv) - THRESHOLD))
wrong = [r for r in runs if ((r['down_rise'] > THRESHOLD) != (not r['flow']))]
log(' misclassified: %d of %d' % (len(wrong), len(runs)))
board('cd /data && GFSINK=/dev/glowforge nohup grblHAL_glowforge -p 23 '
'-e /data/EEPROM-glowforge.DAT > /data/glowforge.log 2>&1 & sleep 2; true')
log('controller restarted')
logf.close()
if __name__ == '__main__':
sys.exit(main())