2 "description": "The bell cymbal (cymbal-bell-v1 geometry, material and listener) hit once with the challenge's stick pulse (1000 N peak, 1 ms) at t = 0.1 s but at the foot of the bell: the footprint (radius 5 mm) starts 2 mm outside the bell's edge at r = 55 mm, at x = 62.0 mm on the x axis. Same solver and grid as the top of the bell chain (4 mm, 300 symmetric shell modes, two steps per sample), on the GPU; the strike normalization is recomputed for the local surface. Peak 43.5 Pa at the listener; rms 7.37 Pa over 0.1 to 0.6 s and 0.40 Pa over 1 to 2 s; spectral centroid 6058 Hz early and 783 Hz later. Scale 160 Pa.",
3 "challenge_geometry": "cymbal-bell-v1",
4 "strikes": [
5 {
6 "t": 0.1,
7 "force": 1000.0,
8 "duration": 0.001,
9 "x": 0.062,
10 "y": 0.0
11 }
12 ],
13 "parameters": {
14 "grid_spacing_m": 0.004,
15 "cells": 8112,
16 "n_dof": 33268,
17 "transverse_modes": 300,
18 "basis_even_in_y": true,
19 "airy_modes": 300,
20 "oversampling": 2,
21 "dt_s": 1.0416666666666666e-05,
22 "highest_transverse_mode_hz": 14038.5
23 },
24 "signal_scale_pa": 160.0,
25 "peak_pa": 43.55,
26 "rms_pa": {
27 "0.1-0.6 s": 7.37,
28 "1-2 s": 0.405
29 },
30 "spectral_centroid_hz": {
31 "0.1-0.6 s": 6058,
32 "1-2 s": 783
33 },
34 "timing_seconds": 655.792,
35 "hardware": "Intel(R) Xeon(R) w5-3435X (32 threads), numpy/scipy for the setup; coupling tensor and time stepping on NVIDIA RTX 6000 Ada Generation (PyTorch 2.14.0+cu130)",
36 "note": "Experiment with a strike position; not a solution of any challenge."
37}