System

Surgical Robot System (se-surgical-robot), QC review session. The project held 402 requirements across six documents (STK: 12, SYS: 18, SUB: 128, IFC: 48, ARC: 15, VER: 181) and 368 trace links. No orphan requirements; all requirements had rationale and verification set. airgen lint returned 135 findings — 4 high, 18 medium, 113 low (mostly undeclared acronyms). The decomposition status fact was in-progress despite the prior session target recording “first-pass complete: 13 subsystems, 78 PART_OF facts, 323 reqs”. Status advanced to qc-reviewed at session close.

Findings

The 4 high-severity findings were ontological mismatches: {{entity:procedure data recorder}} ({{hex:50851208}}), {{entity:power management subsystem}} ({{hex:54F53018}}), {{entity:motion control}} ({{hex:40A53A08}}), and {{entity:time compute node}} ({{hex:50A50208}}) all carry physical environmental constraints in requirements (SUB-MAIN-086, SUB-MAIN-102, VER-MAIN-107) but were classified without the Physical Object trait. The mismatch indicates requirements written against hardware embodiments that the ontology had not captured.

The 18 medium findings split into two patterns. The first: four regulated components — {{entity:motion control system}} ({{hex:51F73A18}}), {{entity:motion scaling module}} ({{hex:50B53B18}}), {{entity:workspace safety enforcer}} ({{hex:51B73818}}), and {{entity:power management subsystem}} — lacked any compliance requirements pointing to IEC 62304, IEC 61508, IEC 60601-1, or FDA QSR. The second: four system-essential components — {{entity:procedure data recorder}}, {{entity:time protocol engine}} ({{hex:50B57B08}}), {{entity:haptic feedback subsystem}} ({{hex:55F57018}}), and {{entity:power management subsystem}} — had no redundancy or failover requirements.

Coverage gaps: the concept surgeon from {{stk:STK-MAIN-012}} had no explicit SUB-level decomposition; {{sys:SYS-MAIN-018}} (cryptographic command authentication) had no corresponding subsystem requirement.

Two spray patterns were identified: {{sys:SYS-MAIN-002}} (single-point failure → safe state) had 39 trace links and {{sys:SYS-MAIN-001}} (motion scaling performance) had 13 links. Link rationale was present on all links, so these were not removed — SYS-MAIN-002 is a safety requirement that legitimately cascades to every subsystem.

Corrections

Physical embodiment (4 high findings → 4 new SUB requirements):

• {{sub:REQ-SESURGICALROBOT-086}}: PDR 1U rack-mount enclosure, IP21, WORM SSD, cart-integrated
• {{sub:REQ-SESURGICALROBOT-087}}: PMS as two LRUs — mains entry module and console power board — galvanically isolated
• {{sub:REQ-SESURGICALROBOT-088}}: MCS as dedicated PCIe motion controller card, 45°C without forced cooling
• {{sub:REQ-SESURGICALROBOT-089}}: TCN as M.2 timing module, IEEE 1588v2 PTP grandmaster, ±500ns accuracy

Compliance requirements (4 regulated components → 4 new SUB requirements):

• {{sub:REQ-SESURGICALROBOT-090}}: MCS — IEC 62304 Class C + IEC 60601-1 PEMS
• {{sub:REQ-SESURGICALROBOT-091}}: WSE — IEC 61508 SIL 3, HFT ≥ 1, <10⁻⁷ PFH
• {{sub:REQ-SESURGICALROBOT-092}}: MSM — 21 CFR Part 820 DHF, MISRA C:2012, IEC 62366-1 human factors
• {{sub:REQ-SESURGICALROBOT-093}}: PMS — IEC 60601-1 isolation, <10µA leakage, IEC 60601-1-2 EMC

Redundancy requirements (4 system-essential components → 4 new SUB requirements):

• {{sub:REQ-SESURGICALROBOT-094}}: PDR → 500ms storage failover, no data loss, surgeon notification within 1s
• {{sub:REQ-SESURGICALROBOT-095}}: TPE → ±2µs holdover for 30 minutes on TCXO secondary oscillator
• {{sub:REQ-SESURGICALROBOT-096}}: HFS → per-axis degraded haptic mode, 200ms warning, full motion retained
• {{sub:REQ-SESURGICALROBOT-097}}: PMS → dual redundant safety-domain rails, 5ms switchover, 60s UPS

Coverage gaps (2 new SUB requirements + 3 trace links):

• {{sub:REQ-SESURGICALROBOT-098}}: CDMS HMAC-SHA-256 command authentication, per-message, ≤1ms — derives from {{sys:SYS-MAIN-018}}
• {{sub:REQ-SESURGICALROBOT-099}}: VIS stereo HD, <50ms latency, ≤1 dropped frame per 10s — derives from {{sys:SYS-MAIN-003}}

Two verification entries added: REQ-SESURGICALROBOT-100 (PDR failover FMEA injection test) and REQ-SESURGICALROBOT-101 (PMS dual-rail switchover bench test).

Power Management Subsystem — Internal

flowchart TB
  n0["Main Power Distribution Unit"]
  n1["UPS Battery Module"]
  n2["Auxiliary Power Supply"]
  n3["Power Sequencing Controller"]
  n1 -->|48VDC bulk| n0
  n0 -->|CAN FD status| n3
  n3 -->|discrete control| n2
  n3 -->|sequencing commands| n0

Residual

The 113 low-severity findings are acronym expansion issues (CBR, WORM, SHA, RAID, etc.). These are editorial quality issues that do not affect verifiability or traceability. A glossary document is the correct fix but exceeds this session’s budget.

The surgeon concept coverage gap in STK-MAIN-012 is now partially addressed by REQ-099 (VIS delivery to surgeon). The broader surgeon workflow decomposition (ergonomics, fatigue, consent) remains to be addressed in a future session.

Spray patterns on SYS-MAIN-002 and SYS-MAIN-001 are accepted as genuinely broad safety requirements; all links have rationale.

Next

Status: qc-reviewed. Ready for validation (Flow D). Next session should: (1) run airgen verify run and address remaining VER coverage below 50% threshold, (2) assess whether the surgical robot system passes validation criteria, and (3) if passing, add to COMPLETED_SYSTEMS and select a new domain for decomposition.