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 shadowing (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
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