Where Truss teaches with a dimensionless pin-jointed solve, Armature answers like the professional tool it imitates (Karamba3D): pick one of 16 parametric structures — beams, portal/gable/multi-storey/three-hinge frames, Warren/Pratt/Howe/bowstring trusses, timber king-post/Fink/scissor roofs, a Vierendeel, an arch, an underslung trussed beam — or draw your own frame from a blank canvas, or import one (OBJ line models from Rhino, Relax structural-net hand-offs, the tool's own JSON). Give each member group a real material and a real catalog cross-section, load it in kN and kN/m with self-weight computed from the sections, and read utilization coloring, moment/shear/axial diagrams, deflections in true millimetres — then let the optimizer walk each group's catalog to the lightest adequate section, Karamba's signature move. And when a model can't stand, the mechanism advisor draws its zero-energy motion and suggests — with one-click fixes — the member, support, or rigid joint that stands it up.
Runs entirely in your browser — nothing is uploaded. The math it shares with professional FEA: the same first-order matrix method SAP2000/RFEM/Karamba3D run first — exact within that theory. What professional analysis adds that this does not: 3D and lateral-torsional buckling, second-order P-Δ, γ-factored design values and code load combinations, buckling curves beyond bare Euler, connections, dynamics — and a licensed engineer who signs it. Use it for intuition and rough proportions; export forces as CSV, centrelines as OBJ for Rhino, the model as JSON.