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Open Source Software

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Evolutionary Mission Trajectory Generator (EMTG)

EMTG is an automated tool for the preliminary design of interplanetary space trajectories. EMTG is designed to generate trajectories with minimal user input, allowing an analyst to accomplish a mission design task in less time and for less cost than traditional methods.

EMTG Goals

EMTG is a fully automated tool for the design of interplanetary missions using either high-thrust chemical or low-thrust electric propulsion as well as planetary flyby manoeuvres. EMTG is capable of determining both the optimal flyby sequence (using an integer genetic algorithm) and also the optimal trajectory (using a nonlinear programming solver and monotonic basin hopping). The outputs of EMTG are medium fidelity - suitable for trade studies and proposals but not for operations. EMTG is composed of two components. The core EMTG program is written in C++ and is driven by a text script interface. The second component is a graphical user interface (GUI) written in Python which is used to process EMTG input and output scripts. The two programs are independent but complimentary.

Project Goals

The purpose of EMTG is to provide a fast and robust mission design environment that allows the user to quickly and inexpensively perform trade studies of various mission configurations and conduct medium-fidelity analysis.

Functional Goals

EMTG can be used to design low-thrust and high-thrust missions in interplanetary space at medium fidelity. It is hoped that the open-source process will give us access to other talented developers who can help improve speed and robustness.

Evolvability Goals

EMTG should evolve the capability to generate high-fidelity trajectories based on its current medium-fidelity capabilities, either by itself or through interactions with the General Mission Analysis Toolkit (GMAT), Goddard’s open-source high-fidelity tool. EMTG should be easy to extend to other models and methods as the need arises.

Usability Goals

EMTG should be usable by any trained astrodynamicist through either a graphical user interface or a script interface. Both interfaces should be simple and self-explanatory. EMTG should require minimal user interaction to perform its functions.

Software Packages

This software is released under the terms and conditions of the NASA Open Source Agreement (NOSA) Version 1.1 or later.

EMTG Software Package

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  • Page Last Updated: October 24, 2019
  • Page Editor: Adil Anis
  • NASA Official: Darryl Mitchell