Aerospace Vehicle Trajectory Design and Optimization Within a Multi-Disciplinary Environment

A trajectory design and optimization tool named Mission is developed to operate within a multi-disciplinary analysis tool environment for conceptual design of aerospace vehicles. Mission possesses several features designed to facilitate its set-up and operation within the environment. It receives input via an Extensible Markup Language tagged data file. The tree structure of the tags reflects that of a branched and multi-segmented trajectory, aiding parsing and editing for set-up of data exchange within the environment. Mission uses Xerces, a public domain library, for parsing data files. In addition, it is linked to both gradient-based andgeneticalgorithm-basedoptimizers,allowingachoicedependingontheamountofapriori informationavailable.Whenlittleisknownaboutthecontrolvariables,aninitialguessoftheir histories may be forgone by initializing the optimization process with the genetic algorithm. Once a solution is approached, the gradient-based method is used. This strategy increases the robustness and autonomy of the trajectory tool operation within the multi-disciplinary environment. Finally, Mission’s trajectory integration process is coded for parallel execution via the Message Passing Interface standard. The resultant execution speed increase reduces the relative expense of operating Mission within the multi-disciplinary environment. The resultsofaCrewTransferVehicle“abortfromascent”problemarepresentedtodemonstrate and quantify Mission’s features.