ADCS.CONOPS.goals.vector_goals.sun_goal module

class ADCS.CONOPS.goals.vector_goals.sun_goal.Sun_Goal(boresight_name=None)

Bases: Vector_Goal

Sun-pointing vector goal.

This goal commands alignment with the spacecraft-to-Sun inertial direction \(\mathbf{s}_{ECI}\):

\[\hat{\mathbf{s}} = \frac{\mathbf{s}_{ECI}}{\|\mathbf{s}_{ECI}\|}, \qquad \mathbf{r}_{goal} = \hat{\mathbf{s}}.\]

Over typical ADCS control horizons (seconds to hours), the Sun direction is treated as inertially fixed, so the feed-forward reference angular velocity is set to zero:

\[\boldsymbol{\omega}_{ref} = \mathbf{0}.\]

Parameters:

boresight_name (str | None)

to_ref(os0)

Generate a reference inertial direction and angular velocity.

Subclasses must implement this method to compute a desired inertial reference vector

\[\mathbf{v}_{\mathrm{ref}} \in \mathbb{R}^3\]

based on the current orbital state. The returned vector is expected to be nonzero and will typically be normalized by the downstream error computation.

Parameters:

os0 (Orbital_State) – Current orbital state.

Returns:

Reference inertial direction and reference angular velocity.

Return type:

Tuple[numpy.ndarray, numpy.ndarray]