Preprint · cad-bench/v0.5 · sweep 2026-04-12open · MIT
CAD·Benchv0.5
← all agents

Spline AI

D · Non-CAD Asset
composite 17.0 [10.7, 25.9]p5 0.0IRT θ 0.0
Spline.design· v2.7· released 2026-01-09· Diffusion-3D· emits Mesh· proprietary

Aimed at game/UX assets, not engineering CAD. Included as a non-CAD baseline to quantify the gap.

L1 GeomL2 EngL3 MfgL4 Cogvs. human
solid: agent · dashed: human baseline

PER-CATEGORY SCORE (95 % CI)

Geometric Primitives
0.0
Boolean Robustness
23.1
BREP Fidelity
23.7
Free-form Surfaces
88.7
Parametric Mechanical Parts
19.4
Assembly & Mating
4.6
Standards Compliance
2.3
Sheet-Metal Bodies
19.3
Sealing-Groove Design
23.9
Kinematic Mechanisms
6.1
DFM · 3-Axis CNC
0.0
DFM · Injection Mould
6.9
DFM · FDM 3D Print
37.9
CAM Toolpath Validity
6.8
Constraint Solving & Editability
3.8
Reverse Engineering
12.8
2-D Sketch Constraints
12.1
Functional Intent · FEA-Gated
8.0
Paraphrase Robustness
60.3
Confidence Calibration
21.9

MEAN METRICS BY LAYER

L1 · Geometry
CategoryVol IoUChamferHausdorffNormConsWatert.Manif.EulerSTEP RTP@1
Geometric Primitives0.0000.000
Boolean Robustness0.0650.860
BREP Fidelity0.850
Free-form Surfaces0.1530.7910.831
L2 · Engineering
CategoryDim RMSEGD&TFeatRecMatingFit-ClsStd
Parametric Mechanical Parts0.5390.0280.093
Assembly & Mating0.0910.0460.001
Standards Compliance0.0270.019
Sheet-Metal Bodies0.5680.085
Sealing-Groove Design0.5410.018
Kinematic Mechanisms0.0970.044
L3 · Manufacturing
CategoryDFMDraftMin-WallCAM-ReachSuppWall-Unif
DFM · 3-Axis CNC
DFM · Injection Mould0.0500.0930.063
DFM · FDM 3D Print51.6000.0990.957
CAM Toolpath Validity0.044
L4 · Cognition
CategoryParamEditConSolveP-RangeFEA-σPara σSeed σBrierEditLat
Constraint Solving & Editability0.0460.0500.019
Reverse Engineering
2-D Sketch Constraints0.045
Functional Intent · FEA-Gated0.046
Paraphrase Robustness0.0630.096
Confidence Calibration0.281

TASK-BY-TASK ARTIFACTS

PRIM-001Hollow cylinder (60 × 40 × 100)0.0000.00PRIM-007Right hexagonal prism with pitch fillet0.0000.00BOOL-003Coplanar-face union (knife-edge stress)0.0440.00BOOL-009High-genus subtraction (lattice block)0.0850.00BREP-004NURBS-handle goblet (G2 swept loft)0.0000.00SURF-002Compressor blade (NACA 65-(12)10)0.5480.00MECH-014L-bracket with M6 + slotted hole0.0000.00MECH-022Stepped shaft with retaining-ring groove0.0920.00MECH-027Planetary-gear carrier plate0.0000.00ASM-005Pin-in-hole, H7/g6 sliding fit0.0000.00ASM-011Dovetail slide (60° flanks)0.0170.00STD-002ISO 4762 M8×30 socket-head cap screw0.0000.00SHEET-003U-channel bracket, 1.5 mm Al, k=0.400.0520.00SEAL-001AS568-214 face-seal groove0.0000.00KIN-002Four-bar linkage, Grashof crank-rocker0.0270.00DFMCNC-0023-ax-machinable manifold block0.0000.00DFMMOLD-002Injection-mouldable enclosure half0.0000.00DFMFDM-008FDM-printable hinge (no support)0.1230.00CAM-0015-pocket plate, Ø3 endmill finish0.0000.00PARAM-006Editable flange (bolt circle param sweep)0.0000.00PARAM-013Editable bracket (length+30 %, hole→M8)0.0000.00REVENG-002Three-view ortho → bracket0.0000.00REVENG-009Three-view ortho → housing with cores0.2040.00SKETCH-003Tangent-arc transition profile0.0000.00FUNC-001Cantilever bracket — 250 N tip load, 6061-T6, SF≥40.0000.00FUNC-007Heat-sink fin array for 25 W TO-2200.0000.00PARA-0015× paraphrased L-bracket0.4260.00CAL-003Confidence-calibrated planetary carrier0.0000.00