vulcan::environment::eclipse Namespace Reference

Namespaces
namespace	constants

Functions
template<typename Scalar>
Scalar	shadow_cylindrical (const Vec3< Scalar > &r_sat, const Vec3< Scalar > &r_sun, double R_body=vulcan::constants::earth::R_eq)
	Cylindrical shadow function.
template<typename Scalar>
Scalar	shadow_conical (const Vec3< Scalar > &r_sat, const Vec3< Scalar > &r_sun, double R_body=vulcan::constants::earth::R_eq, double R_sun=constants::R_sun)
	Conical shadow function with penumbra.
template<typename Scalar>
Scalar	is_in_shadow (const Vec3< Scalar > &r_sat, const Vec3< Scalar > &r_sun, double R_body=vulcan::constants::earth::R_eq)
	Simple binary eclipse check using cylindrical model.
template<typename Scalar>
Scalar	is_sunlit (const Vec3< Scalar > &r_sat, const Vec3< Scalar > &r_sun, double R_body=vulcan::constants::earth::R_eq)
	Check if satellite is in sunlight.

Function Documentation

is_in_shadow()

template<typename Scalar>

Scalar vulcan::environment::eclipse::is_in_shadow	(	const Vec3< Scalar > &	r_sat,
		const Vec3< Scalar > &	r_sun,
		double	R_body = vulcan::constants::earth::R_eq )

Simple binary eclipse check using cylindrical model.

Returns

1.0 if satellite is in Earth's shadow, 0.0 otherwise

is_sunlit()

template<typename Scalar>

Scalar vulcan::environment::eclipse::is_sunlit	(	const Vec3< Scalar > &	r_sat,
		const Vec3< Scalar > &	r_sun,
		double	R_body = vulcan::constants::earth::R_eq )

Check if satellite is in sunlight.

Returns

1.0 if sunlit, 0.0 if in shadow

shadow_conical()

template<typename Scalar>

Scalar vulcan::environment::eclipse::shadow_conical	(	const Vec3< Scalar > &	r_sat,
		const Vec3< Scalar > &	r_sun,
		double	R_body = vulcan::constants::earth::R_eq,
		double	R_sun = constants::R_sun )

Conical shadow function with penumbra.

More accurate model accounting for the finite size of the Sun. Returns smooth transition through penumbra.

Based on Montenbruck & Gill "Satellite Orbits" Section 3.4

Parameters

r_sat	Satellite position in ECI [m]
r_sun	Sun position in ECI [m]
R_body	Shadowing body radius [m]
R_sun	Sun radius [m]

Returns

Illumination factor ν ∈ [0,1]

shadow_cylindrical()

template<typename Scalar>

Scalar vulcan::environment::eclipse::shadow_cylindrical	(	const Vec3< Scalar > &	r_sat,
		const Vec3< Scalar > &	r_sun,
		double	R_body = vulcan::constants::earth::R_eq )

Cylindrical shadow function.

Returns 0 when in complete shadow (umbra), 1 when fully sunlit. Uses cylindrical approximation (Earth's shadow is a cylinder).

Template Parameters

Scalar

double or casadi::MX

Parameters

r_sat	Satellite position in ECI [m]
r_sun	Sun position in ECI [m]
R_body	Radius of shadowing body [m] (default: Earth equatorial)

Returns

Shadow function ν ∈ [0,1]