Solutions Manual Orbital Mechanics for Engineering Students Third Edition Chapter 12
ˆ
r=r
r
ˆ
w=r´v
r´v
ˆ
s=ˆ
w´ˆ
r
ˆ
w´ˆ
r
Compute the position of the moon relative to the satellite:
.
Compute the perturbing acceleration of the moon:
pmoon
m
r
m s
rm s
3r
m
rm
3
(Equation 12.117).
Compute the sun’s geocentric equatorial position vector
by means of Algorithm 12.2, and the
earth-to-sun unit vector
.
Calculate the value of the shadow function
from
and
using Algorithm 12.3
Compute the solar radiation perturbation
psun
S c
CRAsm
ˆ
uS
(Equations 12.97 and 12.98).
Calculate the total perturbing acceleration,
.
Compute the components of the perturbing acceleration along the rsw axes:
Use Equations 12.84 to calculate the components of
in Equation j.
The procedure is implemented in the following MATLAB code, after which the plots of the variations are
shown.
% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
function problem_12_47
% This function solves Problem 12.47 by using MATLAB‘s ode45 to integrate
% Equations 12.84, the Gauss variational equations, for lunar
% gravitational and solar radiation pressure perturbation.
%
% User M–functions required: sv_from_coe, lunar_position, solar_position,
% los
% User subfunctions required: rates
%
% The M-function rsmooth may be found in
% Garcia, D., 2010, “Robust smoothing of gridded data in one and higher
% dimensions with missing values.” Computer. Stat. Data Anal. 54,
% 1167–1178.
%
% The M-function toptitle may be found in
% Marchand, P. and O. T. Holland, 2003, Graphics and GUIs with MATLAB,
% 3rd Edition. Chapman & Hall/CRC.
% –———––—––—–––——––––—–————–––——––––————–—–––——–––—–
global JD %Julian day
%...Preliminaries:
close all