SolarRadiationPressureModel.h

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/*
Solar Radiation Pressure model header file
 
Author: Sam Matez
*/
 
#ifndef MODELS_SOLAR_RADIATION_PRESSURE_MODEL_H
#define MODELS_SOLAR_RADIATION_PRESSURE_MODEL_H
 
// #include "six_dof_dynamics/Body.hpp"
#include "core/macros.h"
#include "architecture/Tasks.h"
#include "utils/frameutils.hpp"
#include "simulation/Model.h"
#include "utils/unitutils.h"
 
namespace modelspace {
 
    /**
     * @brief   Solar Radiation Pressure Model
     * 
     * This model calculates the solar radiation pressure 
     * perturbation that acts on a body in orbit.
     * The methods and calculations in this model come from 
     * https://freeflyer.com/_help_Files/spherical_srp.htm 
     * 
     * Author: Sam Matez
     * Email: sam.matez@attx.tech
     * 
    */
    class SolarRadiationPressureModel : public Model {
    public:
        // Model params
        //         NAME                     TYPE                    DEFAULT VALUE
        START_PARAMS
            /** The solar flux , defaults to the mean solar flux at one astronomical unit (W/m^2) */
            SIGNAL(S,                       double,                 1358.0)
        END_PARAMS
 
        // Model inputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_INPUTS
            /** The body coefficient of reflectivity () */
            SIGNAL(C_r,                      double,                 1.0)
            /** The area of the body subject to solar radiation (the mean area that faces the sun) (m^2) */
            SIGNAL(A_srp,                   double,                 1.0)
            /** The body position wrt the Sun in any generic frame (m) */
            SIGNAL(position_body_sun_f,   CartesianVector3D,      CartesianVector3D({clockwerk::AU_TO_METERS, 0.0, 0.0}))
            /** The solar eclipse factor - ranges from 0 (lowest) to 1 (highest) Depending on magnitude of Earth's shadow */
            SIGNAL(v,                       double,                 1.0)
        END_INPUTS
 
        // Model Outputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_OUTPUTS
            /** The force acting on the body due to solar radiation pressure (N) in the smae generic frame as the input */
            SIGNAL(srp_force_body_f,      CartesianVector3D,      CartesianVector3D({0.0, 0.0, 0.0}))
        END_OUTPUTS
 
        // Model-specific implementations of startup and derivative
        SolarRadiationPressureModel();
        SolarRadiationPressureModel(Model &pnt, const std::string &m_name="SRP");
        SolarRadiationPressureModel(SimulationExecutive &e, const std::string &m_name="SRP");
        SolarRadiationPressureModel(Model &pnt, int schedule_slot, const std::string &m_name="SRP");
        SolarRadiationPressureModel(SimulationExecutive &e, int schedule_slot, const std::string &m_name="SRP");
        virtual ~SolarRadiationPressureModel() {}
 
    protected:
        // Execute in protected
        int execute();
 
        // Temporary vectors and variables to carry out our calculations
        double _r;
        double _multiplier;
        CartesianVector3D _unitpos_body_sun_f;
    };
 
}
 
#endif