safety commit

scripts/step_response.py

@@ -0,0 +1,169 @@
+#!/usr/bin/env python3
+"""Run fan step-response test and capture sr,... serial log lines to CSV.
+
+The firmware holds heater duty fixed, steps fan PWM, and logs temperature
+every second. Use the output to see how chamber temp responds to fan changes.
+
+Example:
+  ./step_response.py
+  ./step_response.py --temp 45 --heater 35 -o logs/stepresp.csv
+"""
+
+from __future__ import annotations
+
+import argparse
+import re
+import sys
+import time
+from datetime import datetime, timezone
+from pathlib import Path
+
+from capture_csv import decode_line, open_serial, resolve_port
+
+SR_RE = re.compile(
+    r"^sr,(?P<ms>\d+),(?P<phase>\w+),(?P<step>\d+/\d+),"
+    r"(?P<heater>\d+),(?P<fan>\d+),"
+    r"(?P<avg>[\d.]+),(?P<min>[\d.]+),(?P<max>[\d.]+),(?P<spread>[\d.]+)"
+    r"(?:,(?P<temps>.*))?$"
+)
+DONE_RE = re.compile(r"^stepresp: done")
+FAIL_RE = re.compile(r"^stepresp: abort")
+
+HEADER = (
+    "wall_time,ms,phase,step,heater_pct,fan_pwm,fan_pct,avg_c,min_c,max_c,spread_c,"
+    "ch2_t,ch3_t,ch4_t,ch5_t"
+)
+
+
+def fan_pct(pwm: int) -> int:
+    return (pwm * 100) // 255
+
+
+def send_command(ser, command: str, timeout: float = 3.0) -> list[str]:
+    ser.write((command.strip() + "\n").encode("utf-8"))
+    ser.flush()
+    lines: list[str] = []
+    deadline = time.monotonic() + timeout
+    while time.monotonic() < deadline:
+        raw = ser.readline()
+        if not raw:
+            continue
+        line = decode_line(raw)
+        if not line:
+            continue
+        lines.append(line)
+        if line.startswith("OK ") or line.startswith("ERR "):
+            break
+    return lines
+
+
+def parse_sr_line(line: str) -> dict | None:
+    match = SR_RE.match(line)
+    if not match:
+        return None
+    data = match.groupdict()
+    temps = data.pop("temps") or ""
+    channels = (temps.split(",") + ["", "", "", ""])[:4]
+    data["ch2_t"], data["ch3_t"], data["ch4_t"], data["ch5_t"] = channels
+    data["fan_pwm"] = data.pop("fan")
+    data["heater_pct"] = data.pop("heater")
+    return data
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Capture fan step-response data")
+    parser.add_argument("-p", "--port", help="Serial port (default: auto-detect)")
+    parser.add_argument("-b", "--baud", type=int, default=115200)
+    parser.add_argument("--temp", type=float, default=45.0, help="Target temperature (C)")
+    parser.add_argument("--heater", type=float, default=35.0, help="Fixed heater duty (%%)")
+    parser.add_argument(
+        "-o",
+        "--output",
+        type=Path,
+        help="Output CSV (default: logs/stepresp_YYYYMMDD_HHMMSS.csv)",
+    )
+    args = parser.parse_args()
+
+    port = resolve_port(args.port)
+    out = args.output
+    if out is None:
+        out = Path("logs") / f"stepresp_{datetime.now():%Y%m%d_%H%M%S}.csv"
+
+    print(f"Port: {port}", file=sys.stderr)
+    print(f"Output: {out}", file=sys.stderr)
+    print(f"Command: stepresp {args.temp:g} {args.heater:g}", file=sys.stderr)
+    print("Ctrl+C to stop\n", file=sys.stderr)
+
+    out.parent.mkdir(parents=True, exist_ok=True)
+    row_count = 0
+
+    with open_serial(port, args.baud) as ser, out.open("w", encoding="utf-8") as fh:
+        fh.write(HEADER + "\n")
+        ser.reset_input_buffer()
+
+        lines = send_command(ser, f"stepresp {args.temp:g} {args.heater:g}")
+        for line in lines:
+            print(line, flush=True)
+        if any(line.startswith("ERR ") for line in lines):
+            return 1
+
+        try:
+            while True:
+                raw = ser.readline()
+                if not raw:
+                    continue
+                line = decode_line(raw)
+                if not line:
+                    continue
+
+                if line.startswith("sr,"):
+                    data = parse_sr_line(line)
+                    if data is None:
+                        print(f"WARN: bad sr line: {line}", file=sys.stderr)
+                        continue
+                    pwm = int(data["fan_pwm"])
+                    wall = datetime.now(timezone.utc).isoformat(timespec="seconds")
+                    row = [
+                        wall,
+                        data["ms"],
+                        data["phase"],
+                        data["step"],
+                        data["heater_pct"],
+                        str(pwm),
+                        str(fan_pct(pwm)),
+                        data["avg"],
+                        data["min"],
+                        data["max"],
+                        data["spread"],
+                        data["ch2_t"],
+                        data["ch3_t"],
+                        data["ch4_t"],
+                        data["ch5_t"],
+                    ]
+                    fh.write(",".join(row) + "\n")
+                    fh.flush()
+                    row_count += 1
+                    if row_count % 30 == 0:
+                        print(
+                            f"  {data['phase']} step {data['step']} "
+                            f"fan={pwm} avg={data['avg']}C spread={data['spread']}C",
+                            flush=True,
+                        )
+                    continue
+
+                if DONE_RE.match(line) or FAIL_RE.match(line):
+                    print(line, flush=True)
+                    break
+
+                if line.startswith("stepresp:"):
+                    print(line, flush=True)
+        except KeyboardInterrupt:
+            print("\nStopping…", file=sys.stderr)
+            send_command(ser, "stepresp stop")
+
+    print(f"Wrote {row_count} rows to {out}", file=sys.stderr)
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())