Full requirement coverage

The SimReady Foundation specification is a numbered registry of requirements grouped by area (naming, geometry, materials, physics, articulation, robot core, etc.). Rigyd’s validator implements the entire registry — every code below is touched on every conversion. For each requirement, the table records:

• Code — the SimReady Foundation requirement code.
• Requirement — what the spec actually asks for.
• Coverage — what Rigyd does with it today, in one of four states:

State	Meaning
Enforced	Actively checked on every conversion. A failure here fails the job.
Runtime / advisory	Inherently a runtime concern (PhysX/Isaac evaluates it at simulation time) or an advisory that requires runtime geometry analysis. Reported as N/A so downstream consumers can see the check was considered, not skipped.
Roadmap — pipeline	Spec area we haven’t shipped yet (semantic labels, non-visual materials, MDL materials, grasp simulation properties). Tracked, not enforced.
Roadmap — articulated / robot	Structurally inapplicable to single rigid-body props. Activates when Rigyd’s articulated-asset and robot generation lands and we move from the Prop-Robotics-Neutral profile to the Robot-Body-* profile family.

Naming & paths (NP)

Code	Requirement	Coverage
NP.001	Prim naming convention	Enforced
NP.002	File naming convention	Enforced
NP.003	Directory structure	Enforced
NP.004	Path length limits	Enforced
NP.005	Asset folder structure	Enforced
NP.006	Metadata location	Enforced
NP.007	Relative paths (no absolute paths in references)	Enforced
NP.008	All referenced asset paths resolve to existing files	Enforced

Atomic asset (AA)

Code	Requirement	Coverage
AA.001	Asset references use anchored paths	Enforced
AA.002	Asset uses only supported file types	Enforced
AA.OV.001	UDIM textures unsupported in Omniverse	Runtime / advisory — UDIM resolution is an Omniverse runtime concern

SimReady metadata (SR)

Code	Requirement	Coverage
SR.001	SimReady metadata in customLayerData	Enforced

Units (UN)

Code	Requirement	Coverage
UN.001	Stage specifies upAxis	Enforced
UN.002	Stage specifies metersPerUnit	Enforced
UN.003	Stage specifies kilogramsPerUnit (if physics present)	Enforced
UN.004	Corrective transforms applied for unit mismatches	Enforced
UN.005	Stage specifies timeCodesPerSecond (if timesamples present)	Runtime / advisory — no timesampled data in static props
UN.006	Stage upAxis = 'Z'	Enforced
UN.007	Stage metersPerUnit = 1.0	Enforced

Hierarchy (HI)

Code	Requirement	Coverage
HI.001	Single root prim hierarchy	Enforced
HI.002	Every UsdGeomPrim has exclusive Xform parent	Enforced
HI.003	Root prim is UsdGeomXformable	Enforced
HI.004	Stage has defaultPrim	Enforced
HI.005	Transforms conform to UsdGeomXformCommonAPI	Enforced
HI.006	Placeable/posable prims are Xformable	Enforced
HI.007	(Reserved by the spec)	Reserved
HI.008	Geometry grouped logically per object structure	Enforced
HI.009	Hierarchy reflects kinematic chain (articulated assets)	Roadmap — articulated / robot
HI.010	No undefined prims (overs)	Enforced

Visual geometry (VG)

Code	Requirement	Coverage
VG.001	At least one imageable geometry	Enforced
VG.002	Boundable prims have valid extent values	Enforced
VG.003	No internal-only geometry	Runtime / advisory — requires runtime visibility analysis
VG.004	Efficient mesh boundaries	Runtime / advisory — requires runtime mesh analysis
VG.005	Meshes maintain appropriate scale	Runtime / advisory — requires scene-context analysis
VG.006	No unnecessary mesh overlap	Runtime / advisory — requires runtime overlap analysis
VG.007	Mesh geometry is manifold	Runtime / advisory — handled during Blender preprocessing
VG.008	No coincident meshes	Runtime / advisory — requires runtime analysis
VG.009	Indexed primvars when values repeat	Enforced
VG.010	No subdivision on meshes with normals	Enforced
VG.011	Only actively used primvars included	Enforced
VG.012	Small meshes combined where appropriate	Runtime / advisory — pipeline preserves input mesh structure
VG.013	Appropriate tessellation density	Runtime / advisory — input tessellation preserved
VG.014	Mesh topology is valid	Enforced
VG.015	Time samples only when values change	Runtime / advisory — no timesampled data in static props
VG.016	No colocated (duplicate) vertex positions	Runtime / advisory — requires runtime point analysis
VG.017	Avoid tessellating primitive shapes	Enforced
VG.018	No unused vertices, edges, or faces in mesh topology	Runtime / advisory — requires runtime topology analysis
VG.019	Faces have non-zero area	Runtime / advisory — requires runtime geometry analysis
VG.020	Points attribute fits 32-bit float precision	Enforced
VG.021	Mesh is triangulated	Enforced
VG.022	Transparent bodies are watertight	Runtime / advisory — requires runtime watertightness analysis
VG.023	Positioning via xform ops, not baked into points	Enforced
VG.024	Identical meshes have consistent connectivity	Runtime / advisory — single-asset pipeline, no repeated meshes
VG.025	Asset positioned at origin (0,0,0)	Enforced
VG.026	Pivot point placed logically	Runtime / advisory — requires domain-specific inspection
VG.027	Non-subdivided meshes have normals	Enforced
VG.028	Mesh normals are valid	Enforced
VG.029	Correct face winding order	Runtime / advisory — requires runtime geometry analysis
VG.034	Avoid invisible prims; use deactivation instead	Enforced
VG.MESH.001	All geometry represented as UsdGeomMesh	Enforced
VG.RTX.001	World-space bounds within RTX limit	Enforced

Visual materials (VM)

Code	Requirement	Coverage
VM.MAT.001	Material bound to all renderable geometry	Enforced
VM.BIND.001	Material bindings use appropriate scope	Enforced
VM.BIND.002	Shader inputs match specification types	Enforced
VM.MDL.001	MDL source assets properly referenced	Roadmap — pipeline (pipeline uses UsdPreviewSurface, not MDL)
VM.MDL.002	MDL shaders use standard OpenUSD attributes	Roadmap — pipeline (pipeline uses UsdPreviewSurface, not MDL)
VM.PS.001	UsdPreviewSurface attributes comply with spec	Enforced
VM.TEX.001	Texture dimensions ≤ 16384 px	Enforced (when textures present)
VM.TEX.002	Correct color space per texture channel	Enforced (when textures present)
VM.D.001	Fewer materials improve performance	Enforced

Non-visual materials (NVM)

Code	Requirement	Coverage
NVM.001	Materials specify non-visual attributes	Roadmap — pipeline
NVM.002	Materials specify base material type	Roadmap — pipeline
NVM.003	Materials specify surface coating	Roadmap — pipeline
NVM.004	Non-visual attributes on bound materials	Roadmap — pipeline
NVM.005	Non-visual properties consistent with visual materials	Roadmap — pipeline
NVM.006	Non-visual properties not time-varying	Roadmap — pipeline

Semantic labels (SL)

Code	Requirement	Coverage
SL.001	All geometry prims semantically labeled	Roadmap — pipeline
SL.003	Semantic labels use SemanticsLabelsAPI schema	Roadmap — pipeline
SL.NV.002	Semantic label attributes have no time samples	Roadmap — pipeline
SL.QCODE.001	Wikidata Q-codes valid and retrievable	Roadmap — pipeline

Physics — rigid bodies (RB)

Code	Requirement	Coverage
RB.001	Asset contains at least one rigid body	Enforced
RB.003	Rigid bodies are UsdGeomXformable prims	Enforced
RB.005	Rigid bodies not part of scene graph instances	Enforced
RB.006	No nested rigid bodies without xformOp stack reset	Enforced
RB.007	Rigid body or collision children have mass specified	Enforced
RB.008	Detailed mass properties (CoM, inertia tensor)	Enforced
RB.009	Rigid body transform has no skew matrix	Enforced
RB.010	Invisible collision meshes have purpose = 'guide'	Enforced
RB.011	Nested rigid bodies have explicit mass or non-zero collision volume	Roadmap — articulated / robot (no nested bodies in single-body props)
RB.012	No nested rigid bodies without connecting joint	Roadmap — articulated / robot (no nested bodies in single-body props)
RB.COL.001	CollisionAPI applied to geometry prims	Enforced
RB.COL.002	MeshCollisionAPI on Mesh prims with CollisionAPI	Enforced
RB.COL.003	MeshCollisionAPI only on UsdGeomMesh prims	Enforced
RB.COL.004	Uniform collision scale for Sphere/Capsule/Cylinder/Cone	Enforced
RB.MB.001	Asset contains at least two rigid bodies (multi-body)	Roadmap — articulated / robot

Physics — joints (JT)

Code	Requirement	Coverage
JT.001	Non-free-floating rigid bodies connected via joints	Roadmap — articulated / robot
JT.002	Joint Body0/Body1 targets exist	Roadmap — articulated / robot
JT.003	Joint Body0/Body1 have at most one target each	Roadmap — articulated / robot
JT.ART.001	Kinematic chains define an articulation	Roadmap — articulated / robot
JT.ART.002	Articulation roots not nested	Roadmap — articulated / robot
JT.ART.003	Articulations not on kinematic bodies	Roadmap — articulated / robot
JT.ART.004	Articulations not on static (disabled) bodies	Roadmap — articulated / robot

Physics — driven joints (DJ)

Code	Requirement	Coverage
DJ.001	Driven joint has correct drive config and joint state	Roadmap — articulated / robot
DJ.002	Driven joints implement joint state API	Roadmap — articulated / robot
DJ.003	Driven joints maintain correct transform and state	Roadmap — articulated / robot
DJ.004	Driven joints implement drive or mimic API	Roadmap — articulated / robot
DJ.005	Driven joints have max velocity limits	Roadmap — articulated / robot
DJ.006	Drive joint parameters within reasonable ranges	Roadmap — articulated / robot
DJ.007	Mimic API config valid for coordinated motion	Roadmap — articulated / robot
DJ.008	Robot schema joints exist and defined	Roadmap — articulated / robot
DJ.009	Robot schema links exist and connected	Roadmap — articulated / robot
DJ.010	Robot joint/link relationships valid	Roadmap — articulated / robot
DJ.011	No articulation loops	Roadmap — articulated / robot

Physics — base articulation (BA)

Code	Requirement	Coverage
BA.001	Articulated assets have exactly one ArticulationRootAPI	Roadmap — articulated / robot
BA.002	Non-adjacent collision meshes don’t clash at default pose	Roadmap — articulated / robot

Physics — colliders & PhysX (COL, PHYSX)

Code	Requirement	Coverage
COL.001	SDF collision approximation	Runtime / advisory — PhysX-specific, validated at runtime in Isaac Sim
PHYSX.COL.001	CollisionAPI on Gprim or Xform with PhysxMeshMergeCollisionAPI	Runtime / advisory — PhysX-specific
PHYSX.COL.002	PhysX collider mesh validation	Runtime / advisory — PhysX-specific

Physics — materials & grasp (PMT, GSP)

Code	Requirement	Coverage
PMT.001	Physics material with friction and restitution	Enforced
GSP.001	Grasp simulation properties	Roadmap — pipeline

Runtime — Isaac Sim (ISA)

Code	Requirement	Coverage
ISA.001	Isaac Sim composition requirements	Runtime / advisory — validated at runtime in Isaac Sim

Robot materials (RM)

Code	Requirement	Coverage
RM.001	No nested materials in robot assets	Roadmap — articulated / robot
RM.002	Materials on top-level only in robot assets	Roadmap — articulated / robot

Robot core (RC)

Code	Requirement	Coverage
RC.001	Robot asset folder contains only referenced files	Roadmap — articulated / robot
RC.002	No local override layers masking upstream schemas	Roadmap — articulated / robot
RC.003	Robot and prim naming conventions	Roadmap — articulated / robot
RC.004	Robot asset has representative thumbnail	Roadmap — articulated / robot
RC.005	Physics attributes authored in physics layer	Roadmap — articulated / robot
RC.006	Robot physics schema correctly authored	Roadmap — articulated / robot
RC.007	Robot USDs declare required schemas	Roadmap — articulated / robot
RC.008	Robot USDs declare robot type	Roadmap — articulated / robot
RC.009	Root joint pinned per robot type	Roadmap — articulated / robot

References

• SimReady Foundation — specification home
• SimReady Foundation — features
• SimReady Foundation — profiles
• The SimReady Specification — Omniverse docs
• OpenUSD
• NVIDIA Isaac Sim · Isaac Lab