Reduced Dual-Target Interceptor (dim=28)

ADVANTAGES2 · dim 28

SolvSRK wins. At the comparison noise level, SolvSRK beats the best baseline by at least 10 percentage points of survival, or by at least 0.05 balanced score when survival is tied. Use SolvSRK for this class of problem. All verdicts →

Dual-target proportional navigation engagement with time-sharing radar. States: [radar_state(6), ekf_target1(6), ekf_target2(6), pn_guidance(4), actuator(4), kinematics(2)]. Radar alternates target tracking at 10 Hz between targets. PN gain N=4, closing velocity model from CLRI-3D-S2. Actuator dynamics: 2nd-order with rate limits. Reduced from dim=40 CLRI-MULTI by using sequential time-sharing instead of simultaneous tracking.

Defense autonomy

Problem definition

Zarchan Ch. 4, 8; Bar-Shalom et al. (2001) Ch. 6, 11; Blackman & Popoli (1999) Ch. 7

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 _clri_multi_reduced_rhs(t: float, y: np.ndarray) -> np.ndarray:
    dy = np.zeros(28)

    radar = y[0:6]
    ekf1 = y[6:12]
    ekf2 = y[12:18]
    pn = y[18:22]
    act = y[22:26]
    kin = y[26:28]

    rng = max(radar[0], 1.0)
    rng_rate = radar[1]
    az_r = radar[2]
    el_r = radar[3]
    rcs = max(radar[4], 0.1)
    snr = radar[5]

    dy[0] = rng_rate
    dy[1] = -_CLOSING_VEL * 0.01 * np.sin(0.1 * t)
    dy[2] = (_TARGET_VEL * np.cos(0.3 * t)) / max(rng, 100.0)
    dy[3] = (_TARGET_VEL * 0.5 * np.sin(0.2 * t)) / max(rng, 100.0)
    dy[4] = -0.01 * (rcs - 1.0)
    dy[5] = -0.5 * (snr - rcs / (rng * rng * 1e-6 + 1.0))

    active_target = int(t * _RADAR_SWITCH_HZ) % 2

    meas_phase = np.sin(2.0 * np.pi * _MEAS_UPDATE_HZ * t)
    meas_gain = 0.5 * (1.0 + np.tanh(10.0 * meas_phase))

    tgt1_true_x = 5000.0 - _CLOSING_VEL * t + 100.0 * np.sin(0.3 * t)
    tgt1_true_y = 1000.0 + _TARGET_VEL * t * 0.1
    tgt1_true_z = 500.0 + 50.0 * np.cos(0.2 * t)
    tgt1_true_vx = -_CLOSING_VEL + 30.0 * np.cos(0.3 * t)
    tgt1_true_vy = _TARGET_VEL * 0.1
    tgt1_true_vz = -10.0 * np.sin(0.2 * t)

    gain1 = meas_gain if active_target == 0 else 0.0
    ekf_bw1 = 5.0 * gain1
    dy[6] = ekf1[3] + ekf_bw1 * (tgt1_true_x - ekf1[0])
    dy[7] = ekf1[4] + ekf_bw1 * (tgt1_true_y - ekf1[1])
    dy[8] = ekf1[5] + ekf_bw1 * (tgt1_true_z - ekf1[2])
    dy[9] = ekf_bw1 * (tgt1_true_vx - ekf1[3])
    dy[10] = ekf_bw1 * (tgt1_true_vy - ekf1[4])
    dy[11] = ekf_bw1 * (tgt1_true_vz - ekf1[5])

    tgt2_true_x = 4000.0 - _CLOSING_VEL * 0.8 * t + 80.0 * np.cos(0.4 * t)
    tgt2_true_y = -800.0 + _TARGET_VEL * t * 0.15
    tgt2_true_z = 700.0 - 30.0 * np.sin(0.15 * t)
    tgt2_true_vx = -_CLOSING_VEL * 0.8 - 32.0 * np.sin(0.4 * t)
    tgt2_true_vy = _TARGET_VEL * 0.15
    tgt2_true_vz = -4.5 * np.cos(0.15 * t)

    gain2 = meas_gain if active_target == 1 else 0.0
    ekf_bw2 = 5.0 * gain2
    dy[12] = ekf2[3] + ekf_bw2 * (tgt2_true_x - ekf2[0])
    dy[13] = ekf2[4] + ekf_bw2 * (tgt2_true_y - ekf2[1])
    dy[14] = ekf2[5] + ekf_bw2 * (tgt2_true_z - ekf2[2])
    dy[15] = ekf_bw2 * (tgt2_true_vx - ekf2[3])
    dy[16] = ekf_bw2 * (tgt2_true_vy - ekf2[4])
    dy[17] = ekf_bw2 * (tgt2_true_vz - ekf2[5])

    int_x = 0.0
    int_y = 0.0
    int_z = 0.0

    los1_x = ekf1[0] - int_x
    los1_y = ekf1[1] - int_y
    los1_z = ekf1[2] - int_z
    r1 = np.sqrt(los1_x**2 + los1_y**2 + los1_z**2 + 1.0)
    los1_rate_az = (ekf1[4] * los1_x - ekf1[3] * los1_y) / (r1 * r1)
    los1_rate_el = ekf1[5] / r1

    pn_cmd1_az = np.clip(_PN_GAIN * _CLOSING_VEL * los1_rate_az, -_ACCEL_LIMIT, _ACCEL_LIMIT)
    pn_cmd1_el = np.clip(_PN_GAIN * _CLOSING_VEL * los1_rate_el, -_ACCEL_LIMIT, _ACCEL_LIMIT)

    los2_x = ekf2[0] - int_x
    los2_y = ekf2[1] - int_y
    los2_z = ekf2[2] - int_z
    r2 = np.sqrt(los2_x**2 + los2_y**2 + los2_z**2 + 1.0)
    los2_rate_az = (ekf2[4] * los2_x - ekf2[3] * los2_y) / (r2 * r2)
    los2_rate_el = ekf2[5] / r2

    pn_cmd2_az = np.clip(_PN_GAIN * _CLOSING_VEL * los2_rate_az, -_ACCEL_LIMIT, _ACCEL_LIMIT)
    pn_cmd2_el = np.clip(_PN_GAIN * _CLOSING_VEL * los2_rate_el, -_ACCEL_LIMIT, _ACCEL_LIMIT)

    tau_pn = 0.05
    dy[18] = (pn_cmd1_az - pn[0]) / tau_pn
    dy[19] = (pn_cmd1_el - pn[1]) / tau_pn
    dy[20] = (pn_cmd2_az - pn[2]) / tau_pn
    dy[21] = (pn_cmd2_el - pn[3]) / tau_pn

    w2 = _OMEGA_ACT * _OMEGA_ACT
    two_zw = 2.0 * _ZETA_ACT * _OMEGA_ACT
    blend = 0.5 + 0.5 * np.tanh(5.0 * (0.5 - (active_target % 2)))
    cmd_az = blend * pn[0] + (1.0 - blend) * pn[2]
    cmd_el = blend * pn[1] + (1.0 - blend) * pn[3]

    dy[22] = act[1]
    dy[23] = w2 * (cmd_az - act[0]) - two_zw * act[1]
    dy[24] = act[3]
    dy[25] = w2 * (cmd_el - act[2]) - two_zw * act[3]

    heading_rate = 0.02
    dy[26] = heading_rate * act[0]
    dy[27] = heading_rate * act[2]

    return dy
Parameters
  • _ACCEL_LIMIT = 200
  • _CLOSING_VEL = 300
  • _MEAS_UPDATE_HZ = 100
  • _OMEGA_ACT = 50
  • _PN_GAIN = 4
  • _RADAR_SWITCH_HZ = 10
  • _TARGET_VEL = 50
  • _ZETA_ACT = 0.7
Initial condition
y(0) = [5000, -300, 0.1, 0.05, 1, 20, …] [shape=(28,), min=-800, max=5000]
Horizon
t ∈ [0, 60]

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: high

Default noise: low

Recommendation snapshot

Clean best: SolvSRK

Noisy best: SolvSRK

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: Reduced Dual-Target Interceptor (dim=28) (reduced-dual-target-interceptor-dim-28)

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
1SolvSRK
100%
1,007,47325.33 s0.809
SciPy BDFSciPy
0%
SciPy RadauSciPy
0%
SciPy RK45SciPy
0%
SciPy LSODASciPy
0%
SciPy DOP853SciPy
0%
SciPy RK23SciPy
0%
CVODE BDFexternal
0%
CVODE Adamsexternal
0%
Tsit5external
0%

At Clean, best balanced arm is SolvSRK.

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_reduced_dual_target_interceptor_dim_28_2026,
  title        = {Resonix Evidence Portal: Reduced Dual-Target Interceptor (dim=28)},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/reduced-dual-target-interceptor-dim-28}},
  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