Lambert.h

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/*
Lambert Solver header file
---------------------------
This file contains the ATTX Lambert Solver utility and associated
functions which build upon it.
 
Author: Alex Reynolds
*/
#ifndef GNC_GUIDANCE_LAMBERT_H
#define GNC_GUIDANCE_LAMBERT_H
 
#include "core/CartesianVector.hpp"
#include "core/macros.h"
 
namespace clockwerk {
    /// @brief Function to implement Battin's solution to solve Lambert's problem
    /// @param x1 The initial position vector in Lambert's problem
    /// @param x2 The final position vector in Lambert's problem
    /// @param tof The time of flight, in seconds
    /// @param mu The grativational parameter
    /// @param cfl The number of "continued fraction levels". A higher number generates a more accurate solution. 10 is a good default.
    /// @param tol The solution tolerance -- once met, solution is considered "converged" and returns
    /// @param max_iter The maximum allowable iterations
    /// @param a The semimajor axis of the defined orbit
    /// @param p The semi-latus rectum of the defined orbit
    /// @param v1 The velocity vector at x1 to meet the x2 and TOF constraints
    /// @param v2 The velocity vector at x2
    /// @return Error code corresponding to success/failure
    /// @note Function is implemented from MATLAB code provided by Dr. Pernicka of Missouri S&T
    int lambertSolver(const CartesianVector3D &x1, const CartesianVector3D &x2, double tof,
                      double mu, int cfl, double tol, int max_iter, double &a, double &p,
                      CartesianVector3D &v1, CartesianVector3D &v2);
}
 
#endif