Bouncing ball (impact events)

PARITYS0 · dim 2

No clear winner. The survival gap is under 10 percentage points and the balanced-score gap is under 0.05, so neither SolvSRK nor the best baseline clears the win threshold. Either works — choose on cost, licensing, or integration effort. All verdicts →

Hybrid system with velocity-reversal events; tests event detection

Oscillators & nonlinear dynamics

Problem definition

Canonical benchmark implementation

Canonical RHS excerpt from the registered callable used for this benchmark cell. Expand it to verify the state equations; it is not a standalone runnable fixture.

Show canonical RHS excerpt
def _bouncing_ball_rhs(t, y):
    return np.array([y[1], -9.81])
Parameters
  • No captured parameters; constants are explicit in the RHS excerpt.
Initial condition
y(0) = [10, 0]
Horizon
t ∈ [0, 20]

Canonical RHS excerpt captured from the same registered callable used for the published benchmark. Frozen closure values are summarized below; helper imports and solver settings are intentionally omitted.

Fingerprint

Spread: low

Default noise: none

Recommendation snapshot

Clean best: SciPy Radau

Noisy best: SciPy LSODA

Coverage

14 solver arms · clean + 5 noise levels

Ranked on survival, precision, and speed

Versions & freeze

Methodology →
Freeze
2026-08-13
libsolvsrk
2.3.0
SciPy
1.14
SUNDIALS
CVODE (bundled backend)

20 seeds/cell default · 14 arms · TRL 4–5 · simulation-lab validated · this page: Bouncing ball (impact events) (bouncing-ball-impact-events)

Governed SolvTune benchmark freeze; per-arm medians only. RHS definitions and raw trial rows are not published.

Self-reported by Resonix Labs · not independently verified

Results matrix

Pick an objective and a noise level to rank all arms on survival, median SCD, median nfev, and median wall time. Medians across seeds.

Objective

Best overall trade-off of survival, precision, and speed.

Noise level

#SolverSurvivalSCDnfevWallScore
1SciPy RadauSciPy
100%
16.0391 ms1.000
2TRBDF2external
100%
16.0245.07 s1.000
3SciPy RK23SciPy
100%
15.620<1 ms0.991
4CVODE Adamsexternal
100%
15.6156 ms0.991
5SolvSRK
100%
15.61572 ms0.991
6SciPy RK45SciPy
100%
15.532<1 ms0.987
7Vern9external
100%
15.51143.92 s0.987
8Vern7external
100%
14.9724.01 s0.974
9SciPy DOP853SciPy
100%
14.750<1 ms0.970
10Tsit5external
100%
14.530720 ms0.964
11SciPy LSODASciPy
100%
12.313<1 ms0.911
12SciPy BDFSciPy
100%
10.9512 ms0.878
13CVODE BDFexternal
100%
10.3316 ms0.863
14FBDFexternal
100%
8.39445.10 s0.818

At Clean, best balanced arm is SciPy Radau · SolvSRK survival 100%, SCD 15.6.

Values are medians across seeds, measured by Resonix Labs on Resonix hardware and not independently verified; nfev and wall are on reference lab hardware (indicative). Under injected noise only SolvSRK and the SciPy arms are run. How we measure accuracy → · Verification status →

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Cite this page

Replace the access date. Pin the freeze ID and library versions when comparing against a later export. Cite it as what it is — a self-reported vendor benchmark, not an independently verified result. The note field says so; please keep it.

@misc{resonix_evidence_bouncing_ball_impact_events_2026,
  title        = {Resonix Evidence Portal: Bouncing ball (impact events)},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/bouncing-ball-impact-events}},
  note         = {Self-reported vendor benchmark; internally generated by Resonix Labs and not independently verified. Accessed YYYY-MM-DD. Freeze 2026-08-13; libsolvsrk 2.3.0; SciPy 1.14.}
}

Related

TRL 4–5 · simulation-lab validated · 398 problems · 14 solver arms · clean + 5 noise levels

Freeze: 2026-08-13 · scipy 1.14 · libsolvsrk 2.3.0 · Methodology

Self-reported by Resonix Labs · not independently verified · Verification status