Cooperative Agent (Cooperative Agent, CA)

Definition

A Cooperative Agent (CA) is a concept introduced by Klonowski (2025) in cislunar space situational awareness architecture design, referring to spacecraft in cislunar space that depend on the SSA architecture for mission support. CAs work in coordination with the SSA architecture: CAs utilize the architecture's detection capabilities to complete their own missions, while their mission trajectories also serve as inputs for architecture coverage optimization.

CA Model

In cislunar SSA architecture design, CAs are modeled as transfer spacecraft departing from GEO to L1 or L2:

Transfer Trajectory Generation

CAs generate transfer trajectories through multi-objective optimization, simultaneously optimizing:

  1. Photometric detection threshold maximization: Utilizing the architecture's optical detection capability
  2. Control cost minimization: Minimizing Δv\Delta v consumption

Trajectory Equation

CA transfer trajectories satisfy Circular Restricted Three-Body Problem (CR3BP) dynamics:

x¨=f(x)\ddot{\mathbf{x}} = \mathbf{f}(\mathbf{x})

Boundary Conditions

DestinationInitial OrbitTarget Orbit
L1GEOL1 halo orbit
L2GEOL2 halo orbit

Architecture-Agent Interaction

The interaction between CAs and the SSA architecture manifests as a cost allocation problem:

  • Architecture design must consider coverage of CA transfer trajectories
  • CAs can adjust trajectories to adapt to the architecture's existing detection capabilities
  • The Pareto optimal frontier describes the trade-off between architecture cost and CA cost

Core Elements

Mathematical Definition

A CA is a transfer trajectory τ(t)\tau(t) satisfying CR3BP dynamics, minimizing a multi-objective functional under given boundary conditions:

min⁡J(τ)=[−photometric detection,Δv]\min J(\tau) = [-\text{photometric detection}, \Delta v]

Key Properties

CA trajectory generation involves multi-objective optimization, requiring trade-offs between detection capability utilization and fuel consumption. The CA-architecture interaction forms a bi-level optimization problem.

Application Scenarios

The CA concept applies to high-value asset mission planning in cislunar space crewed missions, commercial lunar missions, and other missions dependent on SSA support.

References

  • Klonowski M, Owens-Fahrner N, Heidrich C, et al. Cislunar space domain awareness architecture design and analysis for cooperative agents[J]. The Journal of the Astronautical Sciences, 2024.
  • Klonowski M. Cislunar Space Situational Awareness Architecture Design and Analysis[D]. University of Colorado Boulder, 2025.