Optimal Sensing Precision for Celestial Navigation Systems in Cislunar Space using LPV Framework
Eliot Nychka, Raktim Bhattacharya
TL;DR
This work tackles robust onboard celestial navigation in cislunar space by casting the nonlinear CR3BP dynamics as a linear parameter-varying (LPV) system and designing observers with guaranteed estimation error bounds. It introduces two convex optimization formulations to jointly optimize the LPV observer gain and the per-sensor precision, ensuring a user-specified bound on the estimation error in either the $\mathcal{H}_2$ or $\mathcal{H}_\infty$ sense. The approach yields a sensor-precision vector $\beta$ (with $\kappa_i = \sqrt{\beta_i}$ or $\sqrt{\beta_i/\gamma}$) and an observer gain $L = X^{-1}Y$ from LMIs that enforce $\|G_{\bar w \rightarrow \epsilon}(s,\rho)\|_p < \gamma$ for all admissible $\rho$ in a convex polytope. Simulation on the CR3BP-based cislunar model demonstrates that the observers can achieve accurate positioning with minimal sensing, providing theoretical guarantees and practical guidance for hardware design in deep-space navigation.
Abstract
This paper introduces two innovative convex optimization formulations to simultaneously optimize the H2/Hinf observer gain and sensing precision, and guarantee a specified estimation error bound for nonlinear systems in LPV form. Applied to the design of an onboard celestial navigation system for cislunar operations, these formulations demonstrate the ability to maintain accurate spacecraft positioning with minimal measurements and theoretical performance guarantees by design.
