With the recent proposals by NASA to conduct crewed missions beyond low earth orbit (LEO), there is a need to better understand and exploit the governing orbital dynamics in cislunar space and other…

This is a $643,213.06 cooperative agreement awarded by NASA to the University of Texas at Austin (UT Austin) to develop new techniques and apply innovative methods for modeling and designing trajectories for crewed spacecraft exploration beyond low Earth orbit. The objective is to rapidly and robustly model, design, and control complicated trajectories and mission scenarios in the challenging, perturbed dynamical environment of cislunar space and beyond. UT Austin, with extensive expertise in computational space flight mechanics and trajectory optimization, will advance the state-of-the-art in crewed spacecraft trajectory design, including developing fast design methods to generate families of solutions rather than point designs. This effort supports NASA's push to send astronauts to the Moon and beyond. The contract does not have a set-aside designation.

With the recent proposals by NASA to conduct crewed missions beyond low earth orbit (LEO), there is a need to better understand and exploit the governing orbital dynamics in cislunar space and other heavily perturbed space environments. The objective of the proposed work is to innovate new techniques and apply recent innovative techniques in state of the art modeling and trajectory design for crewed vehicle exploration. The challenge is to rapidly and robustly model, design and control complicated trajectories and mission scenarios in the context of human exploration of the moon and beyond. The human crewed aspect of the problem and the highly perturbed dynamical environment make for a challenging, unsolved, and customized problem. Specifically the perturbations of the moon, sun and non-spherical gravity make trajectories much more complicated than the near keplerian orbits found in LEO. The chaotic nature of multibody gravity environments and the large computational burden associated with high fidelity models and continuous thrusting (low-thrust) presents a huge design space. The solution methods will take a variety of parallel paths, including aspects of multiple disciplines such as orbital mechanics, dynamical systems, nonlinear optimization, optimal control, perturbation analysis, and high fidelity modeling and simulation. Specific problems to be considered include but are not limited to potential transfers from launch vehicles departing earth, transfers in and around earth-moon space, transfers aiding lunar surface access, abort trajectory calculation, and other related tasks. Approaches to solve the problem will include three-body periodic orbits, fast numerical methods, analytic methods, precomputed databases, initial guess generators, continuation methods, on-board implementation, parallel computing, impulsive, low-thrust and finite thrust trajectory optimization. Resulting algorithms and tools will act as both stand-alone solutions as well as add-on capability to support the existing NASA/JSC tool set. An emphasis will be placed on fast design methods that enable the generation of families of solutions rather than point designs, and rapid generation of complex solutions that traditionally can take hours or days to design and compute. The research will advance state of the practice at NASA/JSC and state of the art for crewed trajectory design and computation, including new methods from the literature, custom adapted to the problems specific to crewed vehicles and associated constraints and objectives. With two decades of experience in computational space flight mechanics and trajectory optimization, the PI from the university of texas at austin s center for space research is uniquely qualified to execute the proposed work. Given NASA s recent push to send astronauts to the moon and beyond, the time is ripe to leverage recent advances and innovate new advances in associated trajectory design and software capabilities.