Analytical Lunar Descent Guidance Algorithm

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The desire to return humans to the moon has motivated the evaluation of existing lunar descent guidance algorithms and the development of new ideas. This paper outlines a design for a targeting algorithm that quickly and reliably generates a two-dimensional reference trajectory and a real-time three-dimensional guidance algorithm that can use this or any reference trajectory as its basis. The targeting algorithm is analytical in a nature and allows for updates to the reference in real time. Monte Carlo analysis demonstrates the reliable performance of the algorithms in both a general sense and for retargeting once the lunar descent has been initiated.


Journal of Guidance, Control, and Dynamics, Vol. 32, No. 3 (May 2009): 915-926. DOI.

Robert H. Bishop was affiliated with the University of Texas at Austin at the time of publication.