What the model can talk about
Every safety-relevant thing is a typed part with regulator-relevant attributes: IntendedUse, Hazard, Harm, RiskControl, Requirement, Architecture, Behavior, VerificationCase, and Evidence.
Layer 01 · Ontology + Methodology
The missing semantic layer for medical devices.
A domain ontology for safety-critical medical devices: purpose-built for regulated systems where architecture, risk, verification, and evidence must stay connected. SysML v2 provides the language. meMO provides the medical-device vocabulary and method.
What the links mean
Every relation is a native SysML v2 connection def —
its name is the verb, its typed ends carry the roles. DerivesFrom,
SatisfiedBy, MitigatesHazard, VerifiedBy, ProducesEvidence.
What must be complete
Rules walk required semantic links and flag missing paths. Every hazard needs a control. Every control needs verification. Every verification needs evidence. Gaps surface before design review.
Package structure
Seven working surfaces under memo::
memo::core
Shared foundationIdentity, traceability, documented/evidence elements, controlled values, and typed semantic relationships.
memo::architecture
What the device is18 Arcadia-inspired layers for context, requirements, behavior, interfaces, hardware, software, risk, cyber, assurance, and decisions.
memo::methodology
How to apply the ontologyProfiles, patterns, rules, workflow steps, quality gates, viewpoints, and project bindings.
memo::viewpoints · views
Who sees whatStakeholder-oriented concerns and concrete projections — diagram and document-backed views from the same model source.
memo::compliance
Regulated outputsControlled artifacts, change management, postmarket traceability, and ISO 14971 risk-management-file views.
memo::examples::gpca
Reference product modelA worked infusion-pump example used to validate and teach the modeling style — from clinical need to evidence view.
Semantic links
Typed connections, not free-form arrows
Requirement
DerivesFrom · SatisfiedBy · DerivesInto
Function
AllocatedTo
Interface
RealizesInterface · CrossesTrustBoundary · BindsToInterface
Verification
VerifiedBy · ProducesEvidence · Validates · IncludedIn
Risk
MitigatesHazard · TracesRisk · AssessedAgainst
Cybersecurity
ThreatenedBy · Exploits · MitigatesVulnerability · ImpactsSafety
Methodology
A starting structure, not an empty model
Risk-proportionate scope
ResolvedMethodology keys scope to SafetyClassKind (A/B/C) and lifecycle stage — not a rigor dial.
Viewpoints (ISO 42010)
Viewpoints per audience and workflow stage; a View binds that intent to content.
Rules & gates
ElementUsageRule and RelationUsageRule carry a RuleStrengthKind; WorkflowSteps and QualityGate exit criteria.
Project binding
ProjectMethodBinding pins a resolved method, with reusable ModelingPatterns and archetypes.