FlatPlateDragModel.h

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/*
Flat plate drag model header file

Author: Alex Reynolds
*/
/*
Metadata for MS GUI:
imdata = {"displayname" : "Flat Plate Aero. Drag",
          "exclude" : False,
          "category" : "Dynamics"
}
aliases = {"cd" : "Drag Coefficient",
           "area" : "S.C. Frontal Area",
           "density" : "Atmos. Density",
           "wind_velo__f" : "Velo. WRT Wind",
           "body_mass" : "Spacecraft Mass",
           "drag_force__f" : "Drag Force"
}
*/

#ifndef MODELS_ACTUATORS_FLAT_PLATE_DRAG_MODEL_H
#define MODELS_ACTUATORS_FLAT_PLATE_DRAG_MODEL_H

#include "simulation/Model.h" 
#include "frames/Frame.h"
#include "frames/Node.h"
#include "frames/frameutils.h"

namespace warptwin {

    /**
     * @brief   Simplified atmospheric drag model which produces a drag force opposite the wind relative velocity 
    */
    MODEL(FlatPlateDragModel)
    public:
        // Model params
        //         NAME                     TYPE                    DEFAULT VALUE
        START_PARAMS
            /** The coefficient of drag for the object. Default value is 1.0 */
            SIGNAL(cd,                      double,                 1.0)
        END_PARAMS

        // Model inputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_INPUTS
            /** The current frontal area of the object (normal to oncoming wind).
                Default is 1.0 m^2 */
            SIGNAL(area,                    double,                 1.0)
            /** The current atmospheric density, in default units kg/m^3 */
            SIGNAL(density,                 double,                 0.0)
            /** The velocity of the object in the wind frame. NOTE: This is not the 
             * relative wind. It is the velocity of the spacecraft in the wind frame */
            SIGNAL(wind_velo__f,            CartesianVector3,      CartesianVector3({0.0, 0.0, 0.0}))
        END_INPUTS

        // Model outputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_OUTPUTS
            /** The drag force on the object. Output is in the same frame as the wind velocity vector.
                Default units are N. */
            SIGNAL(drag_force__f,           CartesianVector3,      CartesianVector3({0.0, 0.0, 0.0}))
        END_OUTPUTS

    protected:
        int16 execute() override; 
    };

}

#endif