Title of Presentation: A Probabilistic Approach to Trajectory Generation in the Presence of Uncertainty

Primary (Corresponding) Author: Jeffrey B Jewell

Organization of Primary Author: NASA Jet Propulsion Laboratory


Abstract: I will discuss development of the software “EPISODE” (Evaluation of the Posterior for the Inference of Solutions of Ordinary Differential Equations) for an implementation of a probabilistic (Bayesian) approach for reasoning about dynamical systems in the presence of uncertainty with application to intelligent mission simulation, trajectory generation, and nonlinear continuous trajectory control, in order to increase life cycle effectiveness and efficiency of the Science Mission Directorate research endeavors, in particular: 1) to reduce mission development time, risk, and cost through advanced simulation and design capabilities, and 2) to increase mission duration and reliability through autonomous operations and control.  The work proposed here provides algorithmic advances for the use of dynamical systems theory and optimal control, an approach to trajectory design that has already achieved a dramatic reduction in mission planning time for the Genesis mission, in solving for the trajectory design in less than ONE day as opposed to 8-12 weeks!! The work proposed here will further the automation and accuracy with which these trajectories can be discovered and optimal control laws synthesized for more complex missions for longer duration, with multiple objectives, over the full spectrum of fuel expense penalty (from longer time low thrust to large control inputs). Although this proposal specifically targets the mission design problem, we note that the EPISODE framework is completely general and may be applied to any engineering problem described by differential equations.  The proposed work directly addresses several of NASA’s strategic objectives including 1) Undertake robotic and human lunar exploration to further science and to develop and test new approaches, technologies, and systems to enable and support sustained human and robotic exploration of Mars and more distant destinations, 2) Conduct robotic exploration across the Solar System for scientific purposes and to support human exploration in particular, explore Jupiter’s moons, asteroids, and other bodies to search for evidence of life, to understand the history of the Solar System, and to search for resources, 3) Develop and demonstrate power generation, propulsion, life support, and other key capabilities required to support more distant, more capable, and/or longer duration human and robotic exploration of Mars and other destinations.