Scope
The Mission Designer module simulates the orbit of your spacecraft, position dynamics of any other objects that may drive the behavior of your spacecraft (called "targets"), and definition of pointing and operational modes of your spacecraft.
Modeling & Ontology#
The Mission Designer module owns the modeling and simulation of the following elements of the spacecraft digital twin:
Mission Time#
This is the start and end epoch of your spacecraft simulation.
Mission Orbit#
The mission orbit is the orbit of your spacecraft. This orbit is captured in the digitial twin model (static data) using the position and velocity at the initial epoch in the simulation. In Mission Designer, orbit propagation uses J2-only force modeling in a variation of parameters (VOP) algorithm to deliver idealized J2 orbit evolution. This relatively simple method is intentional. While orbit designers use J2 to synchronize orbital motion in useful ways, other perturbations are life limiting and compensated for using propulsion systems. When propulsion system modeling is incorporated into Sedaro Satellite, subsatantial perturbations will be incorporated into orbit propagation along with modeling of guidance, navigation, and control algorithms and any thrust used to maintain desired orbital parameters.
Targets#
Targets (ground, space, or celestial) are any other objects whose position dynamics may drive the behavior (active operational mode or pointing) of your spacecraft. Targets can be grouped to efficiently define spacecraft behavior that is consistent with respect to a set of discrete targets.
Pointing Modes#
Pointing modes define the commanded pointing of your spacecraft, either with respect to standard orbit-referenced directions or targets.
Conditions#
Conditions can be used to drive the active operational mode of the spacecraft at each moment in time, and are meant to represent rules that are established in flight software for autonomy or in operations commanding/scheduling to control the active operational mode of your spacecraft.
Operational Modes#
Operational modes of your spacecraft are defined to drive the selection of the active pointing mode at each time step in mission designer and will drive module-specific mode transitions in component electronic loading, dissipation, thermal control, data rates, control modes, and other important dynamics as you build up your digital twin beyond this module. Conditions and timing constraints are applied to these modes, and they are prioritized to enable the solution of the "active operational mode" state of your spacecraft at each time step in a Mission Designer simulation.
Quickstart#
Check out the following walkthroughs to see how Mission Designer can be used to model two notional satellite missions - each with a different and complex mission architecture.