Constellation Optimization

Multi-objective evolutionary algorithms for deployer satellite constellation design

Summary

  • Multi-objective design of debris remediation constellations.
  • Forward-only V3 pipeline with interpolated event catalogues.
  • Explores trade-offs among delta-v, dust mass, and success rate.

Overview

Designing an effective debris remediation constellation requires balancing competing objectives: maximize coverage of potential conjunctions while minimizing satellite count, delta-v budgets, and required dust mass. This is a challenging multi-objective optimization problem with a complex, nonlinear objective landscape shaped by orbital mechanics and stochastic debris encounters.

I developed a V3 optimization pipeline that uses forward-only propagation and pre-computed event catalogues to enable efficient exploration of the design space. The system supports multiple constellation topologies and uses adaptive evaluation policies to balance accuracy against computational cost.

Design Space

The optimizer works with convenient parameterizations that avoid singularities in orbital elements:

Walker Constellation

Parameters: altitude (km), inclination (°)

Classic Walker-delta/star pattern with configurable satellites per plane. Randomized anomalies avoid singular gradients.

Flower Constellation

Parameters: scale, eccentricity, inclination, ω, Ω, M

6D harmonic flower patterns with altitude derived as a = s·RE + RE + 160 km. Perigee guard ensures a(1−e) ≥ RE + 200 km.

Dual Walker

Parameters: alt₁, alt₂, inc₁, inc₂

Two Walker-like shells at different altitudes and inclinations for improved coverage diversity.

Evaluation Pipeline

The V3 pipeline achieves fast evaluation through several key optimizations that enable evolutionary algorithms to explore thousands of candidate designs:

  • Interpolated Event Catalogues: Target states are pre-sampled into state tables and interpolated at runtime, eliminating expensive repeated propagation
  • Forward-Only Propagation: Constellation satellites are propagated once per event to an intercept epoch (default: 2 hours before conjunction)
  • Rust Batch Evaluator: Native backend supports fast batch evaluation with vectorized processing
  • Adaptive Policies: BetaPolicy uses credible interval convergence to stop evaluation early when success rate is confidently estimated

Objectives & Constraints

Minimize

Total Delta-V

Sum of deployment and phasing maneuver costs

Minimize

Dust Mass

Required mass for momentum transfer

Maximize

Success Rate

Fraction of events with feasible remediation

Subject to: max deployment Δv ≤ 0.5 km/s, max phasing Δv ≤ 0.1 km/s, minimum lead time ≥ 20 hours, perigee radius ≥ RE + 300 km

Key Results

Rust-backed Batch evaluation workflow for optimization studies
1,000 Events in reproducible conjunction bank

The optimizer generates Pareto-optimal constellation designs that reveal fundamental trade-offs in the design space. Lower-altitude constellations require less delta-v but achieve lower coverage, while higher-altitude designs improve coverage at the cost of increased fuel requirements.