boinor.threebody.cr3bp_lib_calc

@author: Dhruv Jain, Multi-Body Dynaminitial_guesss Research Group, MSAAE Purdue University

Objectve: Calculates the position [nd] of 5 libration points of a CR3BP system

Functions

lib_pt_loc(SysChars[, conv_tol])

Computes libration points position [nd] for a CR3BP system

newton_raphson_lib_calc(initial_guess, func_coeffs, ...)

Uses Newton-Raphson Method to compute a zero of a function

Module Contents

boinor.threebody.cr3bp_lib_calc.lib_pt_loc(SysChars, conv_tol=1e-12)

Computes libration points position [nd] for a CR3BP system

Parameters:
  • SysChars (object) – Object of Class SystemChars

  • conv_tol (float) – convergence tolerance for Newton-Raphson Method

Returns:

lib_loc – 5 Libration Points, [nd]

Return type:

numpy ndarray (5x3)

boinor.threebody.cr3bp_lib_calc.newton_raphson_lib_calc(initial_guess, func_coeffs, dfunc_coeffs, conv_tol)

Uses Newton-Raphson Method to compute a zero of a function

Parameters:
  • initial_guess (float) – Approximate value of a zero of the function ‘func’

  • func_coeffs (numpy ndarray (6x1)) – Coeffecients of a polynomial function whose zero is to be computed [C_n, C_n-1, C_n-2, …., C_0] Setup: C_n * x^n + C_n-1 * x^(n-1) ….. C0 * x^0

  • dfunc_coeffs (numpy ndarray (6x1)) – Coeffecients of the derivative of function ‘func’ w.r.t ‘x’ whose zero is to be computed [C_n, C_n-1, C_n-2, …., C_0] Setup: C_n * x^(n-1) + C_n-1 * x^(n-2) ….. C0 * x^0

  • conv_tol (float) – convergence tolerance for Newton-Raphson Method

Returns:

initial_guess – zero of function ‘func_coeffs’ within conv_tol

Return type:

float