LvlhFrameManagerModel.h

/******************************************************************************
* Copyright (c) ATTX LLC 2024. All Rights Reserved.
*
* This software and associated documentation (the "Software") are the 
* proprietary and confidential information of ATTX, LLC. The Software is 
* furnished under a license agreement between ATTX and the user organization 
* and may be used or copied only in accordance with the terms of the agreement.
* Refer to 'license/attx_license.adoc' for standard license terms.
*
* EXPORT CONTROL NOTICE: THIS SOFTWARE MAY INCLUDE CONTENT CONTROLLED UNDER THE
* INTERNATIONAL TRAFFIC IN ARMS REGULATIONS (ITAR) OR THE EXPORT ADMINISTRATION 
* REGULATIONS (EAR99). No part of the Software may be used, reproduced, or 
* transmitted in any form or by any means, for any purpose, without the express 
* written permission of ATTX, LLC.
******************************************************************************/
/*
Frams state sensor model header file
 
Author: Alex Reynolds
*/
 
#ifndef MODELS_SUPPORT_LVLH_FRAME_MODEL_H
#define MODELS_SUPPORT_LVLH_FRAME_MODEL_H
 
#include "core/macros.h"
#include "simulation/Model.h"
#include "six_dof_dynamics/Frame.hpp"
#include "utils/frameutils.hpp"
 
namespace modelspace {
 
    /**
     * @brief   LVLV Frame Manager Model
     * 
     * This model creates and maintains the LVLH reference frame 
     * according to the NASA definition here:
     * https://ntrs.nasa.gov/api/citations/19780010162/downloads/19780010162.pdf
     * 
     * It creates a frame as a child of the parent frame parameterized by
     * parent. It locks position to the parent frame, leaves attitude free,
     * then updates attitude at every derivative step according to the LVLH 
     * frame definition.
     * 
     * Definition:
     * +Z axis directed toward the center of the Earth
     * +Y axis perpendicular to the orbit plane with direction opposite angular momentum
     * +X axis completes the right hand frame in the direction of orbit travel
     * 
     * Important: This is a position-only frame. Angular velocity is not updated
    */
    class LvlhFrameManagerModel : public Model {
    public:
        // Model params
        //         NAME                     TYPE                    DEFAULT VALUE
        START_PARAMS
            /** The inertial parent frame which the target frame is orbiting */
            SIGNAL(planet_frame_ptr,        FrameD*,                nullptr)
            /** The reference target frame to which the LVLH frame should attach */
            SIGNAL(target_frame_ptr,        FrameD*,                nullptr)
        END_PARAMS
 
        // Model inputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_INPUTS
            /** This is the orbital position of the object for which we're calculating LVLH */
            SIGNAL(pos__inertial,           CartesianVector3D,      CartesianVector3D())
            /** This is the orbital velocity of the object for which we're calculating LVLH */
            SIGNAL(vel__inertial,           CartesianVector3D,      CartesianVector3D())
        END_INPUTS
 
        // Model outputs
        //         NAME                     TYPE                    DEFAULT VALUE
        START_OUTPUTS
            /** The LVLH frame produced by this model */
            SIGNAL(lvlh_frame_ptr,          FrameD*,                nullptr)
        END_OUTPUTS
 
        // Model-specific implementations of startup and derivative
        LvlhFrameManagerModel();
        LvlhFrameManagerModel(Model &pnt, const std::string &m_name="lvlh_frame_manager");
        LvlhFrameManagerModel(SimulationExecutive &e, const std::string &m_name="lvlh_frame_manager");
        LvlhFrameManagerModel(Model &pnt, int schedule_slot, const std::string &m_name="lvlh_frame_manager");
        LvlhFrameManagerModel(SimulationExecutive &e, int schedule_slot, const std::string &m_name="lvlh_frame_manager");
        virtual ~LvlhFrameManagerModel() {}
    protected:
        int start();
        int execute();
 
        /// @brief  This is the actual LVLH frame
        FrameD _lvlh_frame = FrameD("lvlh_frame");
 
        /// @brief Temporary variable to hold lvlh attitude
        DCMD _lvlh_attitude__r;
 
        /// @brief Temporary variable to hold LVLH angular velociyt in lvlh frame
        CartesianVector3D _lvlh_ang_vel__lvlh;
    };
 
}
 
#endif