3D True PN Engagement
PARITYS0 · dim 6No 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 →
3D engagement with azimuth and elevation LOS rates. True PN (N=3) in both planes against straight-line target.
Problem definition
Zarchan Ch. 3 (3D engagement geometry)
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 rhs(t, y):
rx, ry, rz = y[0], y[1], y[2]
vx_i, vy_i, vz_i = y[3], y[4], y[5]
d = np.empty(6)
R = np.sqrt(rx * rx + ry * ry + rz * rz)
if R < _RANGE_GUARD:
d[:] = 0.0
return d
vx_rel = vx_i - vtx
vy_rel = vy_i - vty
vz_rel = vz_i - vtz
R_dot = (rx * vx_rel + ry * vy_rel + rz * vz_rel) / R
V_c = -R_dot
R2 = R * R
omega_x = (ry * vz_rel - rz * vy_rel) / R2
omega_y = (rz * vx_rel - rx * vz_rel) / R2
omega_z = (rx * vy_rel - ry * vx_rel) / R2
omega_mag = np.sqrt(omega_x**2 + omega_y**2 + omega_z**2)
if omega_mag > _LOS_RATE_CLAMP:
scale = _LOS_RATE_CLAMP / omega_mag
omega_x *= scale
omega_y *= scale
omega_z *= scale
a_x = N * V_c * omega_x
a_y = N * V_c * omega_y
a_z = N * V_c * omega_z
d[0] = vx_rel
d[1] = vy_rel
d[2] = vz_rel
d[3] = a_x
d[4] = a_y
d[5] = a_z
return d- Parameters
- N = 3
- _LOS_RATE_CLAMP = 0.5
- _RANGE_GUARD = 0.1
- vtx = 200
- vty = 30
- vtz = -10
- Initial condition
- y(0) = [5000, 2000, 1000, -250, 0, 0]
- Horizon
- t ∈ [0, 25]
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: extreme
Default noise: low
Recommendation snapshot
Clean best: Vern9
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: 3D True PN Engagement (3d-true-pn-engagement)
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
| # | Solver | Survival | SCD | nfev | Wall | Score |
|---|---|---|---|---|---|---|
| 1 | Vern9external | 100% | 10.4 | 418 | 2.81 s | 0.866 |
| 2 | SolvSRK | 100% | 10.3 | 1,612 | 25 ms | 0.865 |
| 3 | SciPy RadauSciPy | 100% | 10.3 | 2,708 | 35 ms | 0.865 |
| 4 | Vern7external | 100% | 10.0 | 512 | 2.80 s | 0.858 |
| 5 | Tsit5external | 100% | 8.7 | 618 | 708 ms | 0.826 |
| 6 | SciPy DOP853SciPy | 100% | 8.5 | 314 | 2 ms | 0.821 |
| 7 | SciPy RK45SciPy | 100% | 8.1 | 638 | 4 ms | 0.811 |
| 8 | SciPy LSODASciPy | 100% | 7.7 | 407 | 2 ms | 0.803 |
| 9 | SciPy RK23SciPy | 100% | 7.3 | 4,475 | 37 ms | 0.793 |
| 10 | FBDFexternal | 100% | 7.2 | 721 | 3.79 s | 0.790 |
| 11 | CVODE Adamsexternal | 100% | 7.0 | 279 | 8 ms | 0.785 |
| 12 | SciPy BDFSciPy | 100% | 6.7 | 800 | 16 ms | 0.778 |
| 13 | CVODE BDFexternal | 100% | 6.2 | 368 | 9 ms | 0.766 |
| 14 | TRBDF2external | 100% | 4.4 | 4,974 | 3.62 s | 0.723 |
At Clean, best balanced arm is Vern9 · SolvSRK survival 100%, SCD 10.3.
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 →
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_3d_true_pn_engagement_2026,
title = {Resonix Evidence Portal: 3D True PN Engagement},
author = {{Resonix Labs (Canada) Inc.}},
year = {2026},
howpublished = {\url{https://resonixusa.com/evidence/problems/3d-true-pn-engagement}},
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