forked from 1b-agent/fieldcraft-upstream
jyvikoandClaude Opus 5.5
581646bdac
file.sample drop-test: an L-bracket standing on its foot (a SolidCraft script in sample.rs) swept into hex8, falling 2 m onto a rigid floor tilted 15 deg; explicit dynamics for 1 ms with gravity and plasticity. Its test checks the mass against rho V, the impact speed sqrt(2 g h) and kinetic energy, the energy balance and the momentum the floor takes. docs/examples.md starts with it, and its picture is docs/media/examples/drop-test.png. Closes #162 Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo
29 lines
1.8 KiB
Markdown
29 lines
1.8 KiB
Markdown
# Examples
|
||
|
||
Every example is a built-in sample: open it from **File ▸ Samples** (or the start screen), with
|
||
`fieldcraft --sample NAME`, or with the `file.sample` command (`{"name": "drop-test"}`), then
|
||
press **Solve** (`solve.run`). Each opens fully defined — geometry, mesh, materials, boundary
|
||
conditions, loads and steps — in mm, t, s, N and MPa, and opens and solves within half a minute. The geometry is our
|
||
own: SolidCraft scripts run when the sample opens (a recipe from [`tests/corpus`](../tests/corpus)
|
||
or one written in `crates/engine/src/sample.rs`). Each sample has a test in
|
||
`crates/engine/src/sample.rs` that opens it, checks it clean, solves it and holds its result to
|
||
the check given below.
|
||
|
||
## Drop test (`drop-test`)
|
||
|
||
|
||
|
||
An aluminium L-bracket (60 × 40 mm foot, 50 mm upright, 8 mm thick, R6 fillet) falls 2 m onto a
|
||
rigid floor tilted 15°, so the end of its foot strikes first. Explicit dynamics for 1 ms with
|
||
gravity: 1 911 swept hex8 elements (one-point, stiffness hourglass control), bilinear plasticity
|
||
(yield 240 MPa), the floor a rigid wall. About 8 400 increments, a few seconds.
|
||
|
||
**Look at:** the frames from the strike (Results ▸ Frame): the compression wave leaves the
|
||
struck corner and the upright's inertia bends the fillet, where von Mises peaks near 120 MPa —
|
||
below yield, so the drop leaves no permanent set. The energies plot shows the kinetic energy
|
||
turning into vibration with a balance under 0.01 %.
|
||
|
||
**Check:** the mass equals ρ V of the bracket (0.5 %); it meets the floor at √(2 g h) =
|
||
6.26 m/s, with ½ m v² = 1 748 mJ of kinetic energy (1 %); energy is conserved (balance < 1 %);
|
||
by 1 ms the floor has taken about half its downward momentum.
|