Linear Covariance Analysis for Powered Lunar Descent and Landing

A baseline sensor suite consisting of a star camera, an altimeter, gyros, accelerometers, and a velocimeter is examined for the powered lunar descent landing problem using linear covariance techniques. The inertial navigation error during lunar powered descent and landing is determined, and the sensitivities to initial navigation errors, gravity model errors, and individual instrument errors are evaluated. Terrain-relative navigation sensors are introduced into the analysis, and a novel application of linear covariance analysis is used to iteratively determine the sensor specifications needed to meet a 100 m 3-s3-σ landing-error requirement. The sensitivities of landing navigation error to sensor errors, environment modeling errors, and terrain map errors are determined. [PUBLISHER ABSTRACT]