Summary

Extended the scaffold flow with operating environment analysis, external constraint identification, external interface specification, and UHT classification of stakeholders and environmental factors. These changes address the root cause of the surgical robot EMC gap (session 377) — environmental constraints were only discovered at validation because the scaffold phase didn’t capture them.

Changes

Stakeholder classification

Each identified stakeholder is now classified as a UHT entity during scaffold step 10a. Cross-domain analog search runs per stakeholder — a “surgical robot operator” sharing traits with a “nuclear plant operator” can surface cognitive load or training requirements. Stakeholder relationships stored as HAS_STAKEHOLDER facts in Substrate.

Operating environment and external constraints (step 10d)

New scaffold step between stakeholder cross-check and system requirements. Seven constraint categories:

• Physical — temperature, humidity, vibration, shock, IP rating, seismic zone, radiation
• Electromagnetic — EMC/EMI sources, susceptibility, emissions limits (IEC 61000, CISPR 11, MIL-STD-461)
• Power infrastructure — mains voltage/frequency, power quality, backup availability, grounding
• Network/communications — connectivity type, bandwidth, latency, cybersecurity threat model
• Physical space — footprint, weight limits, access constraints, co-located equipment
• Regulatory — standards beyond stakeholder-cited ones, environmental regs, export controls
• Operational tempo — duty cycle, continuous/intermittent, peak load, emergency/surge capacity

Each constraint classified as a UHT entity with cross-domain analog search. Generates STK requirements tagged stk-environment. Stored as HAS_CONSTRAINT facts.

External interface identification (step 10e)

New scaffold step identifying all boundary-crossing interfaces to external systems before decomposition begins. For each external interface: what’s on the other side, what protocol, who owns it, availability/latency assumptions. Each external system classified as a UHT entity. Generates IFC requirements tagged external. Stored as INTERFACES_WITH facts.

Impact

The surgical robot’s EMC requirement (IEC 60601-1-2) was only discovered at validation session 377, 25 sessions after scaffold. Under the new scaffold flow, the OR electromagnetic environment (300kHz–3MHz RF generators adjacent to the surgical system) would be captured at step 10d and generate an EMC stakeholder requirement before any subsystem work begins.

Scaffold phase summary

Step	Phase	UHT classified	Analog search	Output
10a	Identify stakeholders	Yes	Yes	HAS_STAKEHOLDER facts
10b	Roleplay stakeholders	—	—	≥2 STK per stakeholder
10c	Cross-check coverage	—	—	Conflict resolution
10d	Environment & constraints	Yes	Yes	STK (environmental), HAS_CONSTRAINT facts
10e	External interfaces	Yes	—	IFC (external), INTERFACES_WITH facts
11	System requirements	—	—	SYS derived from STK