Accuracy you can check
Every FERS result is produced by a finite-element solver and validated against the closed-form (analytical) solution — the textbook formula. For the standard beam and frame cases below, FERS matches the exact solution to within solver tolerance. That is what makes FERS safe for an AI agent to call and for an engineer to trust.
| Case | Closed-form | Analytical | FERS | Error |
|---|---|---|---|---|
Simply supported beam, uniform load — mid-span deflection L = 6 m, w = 10 kN/m, 200×100 mm steel (E = 210 GPa) | δ = 5wL⁴ / 384EI | 12.05 mm | 12.05 mm | 0.0% |
Simply supported beam, uniform load — maximum moment L = 6 m, w = 10 kN/m | M = wL² / 8 | 45.00 kN·m | 45.00 kN·m | 0.0% |
Cantilever, end point load — free-end deflection L = 5 m, P = 1 kN, IPE180 | δ = PL³ / 3EI | closed form | matches | < 0.1% |
Cantilever, end point load — fixed-end moment L = 5 m, P = 1 kN | M = PL | closed form | matches | < 0.1% |
Simply supported beam, central point load — mid-span deflection closed form | δ = PL³ / 48EI | closed form | matches | < 0.1% |
Cantilever, uniform load — free-end deflection closed form | δ = wL⁴ / 8EI | closed form | matches | < 0.1% |
These closed-form checks are asserted in the open-source FERS test suite and re-run on every release. Beyond hand solutions, FERS also handles second-order (P-Δ) effects, buckling, load combinations, and Eurocode unity checks — each solve returning a transparent hand-calc trace.
Reproduce it yourself
Any agent or script can run these solves. Create an API key at Profile → API Keys, then:
curl -s https://ferscloud.com/api/sdk/solve \
-H "X-API-Key: keyId.secret" \
-H "Content-Type: application/json" \
-d '{ "model": { /* FERS model JSON */ } }'Or connect FERS to Claude, ChatGPT, or Cursor via MCP — see the getting-started guide. First 100 solves each week are free.