Each feature in the production build of GMAT has an engineering specification that defines the working requirements, the user interfaces, and how the feature works. GMAT's features are broken down into several categories to help organize and track related features. Functional specifications are maintained in Google docs primarily because Google docs supports comments and markup during the review phases better than the wiki. Features in GMAT are tracked by requirement Id. For example, the Spacecraft Orbit State feature is governed by the requirement FRR-1.
Links to GMAT's feature specifications are below.
Basic Dynamics and Models Specifications
The basic dynamics model feature area contains features like orbital dynamics models, coordinate systems, attitude models, and solar system models such as planets, Libration points, and barycenter.
Powered Flight Specifications
The powered flight feature area covers features that model impulsive and finite maneuvers.
Solver Infrastructure Specifications
The solver infrastructure feature area covers features related to targeting and optimization.
Programming Infrastructure Specifications
The programming infrastructure feature area covers features like control flow, variables, arrays and interfaces such as the MATLAB interface.
Output and Utility Specifications
The programming infrastructure feature area covers features like reports, plots, and ephemeris files.
Application Control Specifications
The programming infrastructure feature area covers features high level GMAT user interfaces such as the script language and the GUI.