#!/usr/bin/env python3 """Back-schedule the five APQP phases from start of production (SOP) and track deliverables. Phases (AIAG APQP): 1 Plan and define, 2 Product design and development, 3 Process design and development, 4 Product and process validation, 5 Launch, feedback, assessment and corrective action. Phase 4 ends --ppap-lead weeks before SOP (PPAP approval); phase 3 overlaps the second half of phase 2; phase 5 starts at SOP with a --safe-launch period of early-production containment. Durations (weeks: P1, P2, P3, P4) by complexity: low 4/8/8/6, medium 6/16/14/10, high 8/26/20/14. Build-to-print suppliers (--no-design) shorten phase 2 to design-input review and feasibility (1/3 of the time). Usage: python apqp_plan.py --sop 2027-09-06 --complexity medium --today 2026-10-26 python apqp_plan.py --sop 2027-09-06 --complexity high --no-design --status deliverables.csv --today 2027-03-01 Status CSV columns: deliverable, phase (1-5), status (done/in-progress/not-started) Exit codes: 0 schedule feasible and nothing late, 1 compressed schedule or late deliverables, 2 usage error. """ import argparse import csv import datetime as dt import sys DUR = {"low": (4, 8, 8, 6), "medium": (6, 16, 14, 10), "high": (8, 26, 20, 14)} NAMES = ["Plan and define", "Product design and development", "Process design and development", "Product and process validation", "Launch, feedback and corrective action"] DELIVERABLES = { 1: ["Design goals", "Reliability and quality goals", "Preliminary bill of materials", "Preliminary process flow chart", "Preliminary special characteristics", "Product assurance plan", "Management support (gate 1)"], 2: ["DFMEA", "Design for manufacturing and assembly", "Design verification plan and report (DVP&R)", "Design reviews", "Prototype control plan", "Engineering drawings and specifications", "Material specifications", "Team feasibility commitment", "Equipment, tooling and gauge requirements", "Special characteristics list"], 3: ["Packaging standards", "Process flow chart", "Floor plan layout", "Characteristics matrix", "PFMEA", "Pre-launch control plan", "Process instructions", "MSA plan", "Preliminary process capability plan"], 4: ["Significant production run", "MSA evaluation", "Preliminary process capability (Ppk)", "PPAP submission and approval", "Production validation testing", "Packaging evaluation", "Production control plan", "Quality planning sign-off"], 5: ["Safe-launch containment and exit", "Reduced variation (Cpk tracking)", "Customer satisfaction and delivery review", "Lessons learned"], } def wk(d, n): return d + dt.timedelta(weeks=n) def schedule(sop, comp, design, ppap_lead, safe): d1, d2, d3, d4 = DUR[comp] if not design: d2 = max(2, round(d2 / 3)) p4e = wk(sop, -ppap_lead) p4s = wk(p4e, -d4) p3e, p3s = p4s, wk(p4s, -d3) p2s = wk(p3s, -d2 / 2) # phase 3 starts halfway through phase 2 p2e = wk(p2s, d2) p1e, p1s = p2s, wk(p2s, -d1) return [(1, p1s, p1e), (2, p2s, p2e), (3, p3s, p3e), (4, p4s, p4e), (5, sop, wk(sop, safe))] def main(): ap = argparse.ArgumentParser(description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter) ap.add_argument("--sop", type=dt.date.fromisoformat, required=True, help="start of production YYYY-MM-DD") ap.add_argument("--complexity", choices=DUR, default="medium") ap.add_argument("--no-design", action="store_true", help="build-to-print: no product design responsibility") ap.add_argument("--ppap-lead", type=int, default=4, help="weeks between PPAP approval and SOP (default 4)") ap.add_argument("--safe-launch", type=int, default=13, help="weeks of early-production containment (default 13)") ap.add_argument("--today", type=dt.date.fromisoformat, default=dt.date.today()) ap.add_argument("--status", help="deliverable status CSV") a = ap.parse_args() plan = schedule(a.sop, a.complexity, not a.no_design, a.ppap_lead, a.safe_launch) rc = 0 print(f"APQP plan: SOP {a.sop}, {a.complexity} complexity" + (", build-to-print" if a.no_design else "") + "\n") print(f"{'Phase':<44}{'Start':<12}{'End':<12}Gate") for n, s, e in plan: gate = {1: "Program approval", 2: "Design freeze", 3: "Process sign-off", 4: "PPAP approved", 5: "Safe-launch exit"}[n] print(f"{n} {NAMES[n - 1]:<42}{s!s:<12}{e!s:<12}{gate}") start = plan[0][1] if start < a.today and not a.status: # planning a new program: is there still time? short = (a.today - start).days / 7 print(f"\nCOMPRESSED: phase 1 should have started {start}, {short:.0f} weeks ago. Options: run phases in " "parallel with extra resources, reuse carry-over designs/processes, negotiate SOP or a staged PPAP.") rc = 1 if a.status: try: with open(a.status, newline="", encoding="utf-8-sig") as fh: rows = list(csv.DictReader(fh)) except (OSError, csv.Error) as e: print(f"error: {e}", file=sys.stderr) return 2 ends = {n: e for n, _, e in plan} late, done, total = [], 0, 0 listed = set() for r in rows: ph = int(r.get("phase") or 0) st = (r.get("status") or "").strip().lower() listed.add((r.get("deliverable") or "").strip().lower()) total += 1 done += st == "done" if ph in ends and st != "done" and ends[ph] < a.today: late.append(f"phase {ph} '{r['deliverable']}' is {st or 'not started'}; phase ended {ends[ph]}") print(f"\nDeliverables: {done}/{total} done") for msg in late: print(f"LATE {msg}") current = [n for n, s, e in plan if s <= a.today <= e] for n in current: missing = [d for d in DELIVERABLES[n] if d.lower() not in listed] if missing: print(f"Phase {n} deliverables not tracked: {', '.join(missing)}") rc = 1 if late or rc else 0 else: print("\nDeliverables by phase:") for n in range(1, 6): print(f" {n}: " + "; ".join(DELIVERABLES[n])) return rc if __name__ == "__main__": sys.exit(main())