A rapid uncertainty propagation method for pre-parachute phase of Mars entry

Abstract

In this paper, a novel approach is proposed for analyzing evolution of uncertainty in state trajectories of a Mars entry vehicle due to uncertainties in initial conditions and other system parameters. By introducing uncertainty factors, the stochastic dynamical systems are converted into equivalent deterministic dynamical systems in higher dimensional space. And then based on the local linearization and linear system theory, a rapid uncertainty propagation method can be get. Applying the method to a representative entry scenario taken from the NASA MSL-class mission, Simulation results indicate that the proposed method is able to predict evolution of uncertainty, compared with Monte Carlo method, with little degraded accuracy, but with much more computational efficiency.