Path: SC/Disturbances
% Generates solar pressure torques with shadowing.
Models a spacecraft as a collection of areas. Shadowing is done by a zbuffer
algorithm. Each component is modeled as a circular area with a normal and
surface properties. All units are metric.
All outward normals must be expressed in the same coordinate frame.
The shadowing works by comparing the location of the center-of-pressure
of each area with respect to the radius of each area that is closer to
the source. If it is within that area it is eliminated from the calculation.
This will work well if the areas are small or if the largest area is
closest to the source.
Only one source is allowed.
--------------------------------------------------------------------------
Form:
[torque, force, x] = TSolarP( x, uSource, sunIntensity, shadowing )
--------------------------------------------------------------------------
------
Inputs
------
x (:) Element data structure array
.area (1,1) Surface area
.name (1,:) Surface name
.cP (3,1) Center-of-pressure
.normal (3,1) Outward normal
.rhoAbsp (1,1) Absorption coefficient
.rhoSpec (1,1) Specular reflection coefficient
.rhoDiff (1,1) Diffuse reflection coefficient
.rhoTrns (1,1) Transmissivity coefficient
.torque (3,1) Elemental torque
.force (3,1) Elemental force
.shadowed (1,1) 0 = shadowed 1 = unshadowed
uSource (3,1) Source unit vector
sourceIntensity (1,1) Intensity (watts/m^2) default is 1353 watts/m^2
doShadowing (1,1) Any input will cause shadowing to be computed
-------
Outputs
-------
torque (3,1) Total solar pressure torque
force (3,1) Total solar pressure force
x (:,:) Updated data structure (with individual forces
and torques)
--------------------------------------------------------------------------
Math: Linear/Cross Math: Linear/Unit
Back to the SC Module page