Generates the mass properties for the ComStar demo satellite.
The Comstar is a hypothetical geosynchronous communications satellite used to demostrate control system design for satellites. You should run this script first before running any of the other Comstar scripts. Saves data to the mat-file ComStarI.
Since version 2. ------------------------------------------------------------------------- See also Inertias, MassProp, BDDesign, DupVect, DVAKM -------------------------------------------------------------------------
Contents
%-------------------------------------------------------------------------- % Copyright 1996 Princeton Satellite Systems, Inc. All Rights Reserved %--------------------------------------------------------------------------
Constants
%----------
g = 9.806;
rhoAL6061T6 = 2.7651e+03;
First guess
%------------
mSC = 2000;
Spacecraft properties
%---------------------- widthCore = 1.6; widthAntenna = 1.6; mAntenna = 2*0.008*0.2*rhoAL6061T6*pi*(widthAntenna/2)^2; % 20 percent mesh, 8 mm thick lengthSAPanel = 1.6; antennaBoom = 1.6; thicknessSAPanel = 0.02; sAArea = lengthSAPanel*widthCore; sABoom = widthCore/2; nPanelsPerArray = 3; rhoSolarPanel = 64.1/(6*3.2); mSA = 2*nPanelsPerArray*sAArea*rhoSolarPanel; power = 0.142*nPanelsPerArray*sAArea*1358; mEL = 0.001*power*63; mPayload = 300; iSPSolid = 285; rhoSolid = 1.7574e+03; rhoFuel = 1000; iSPACS = 220; uSolid = g*iSPSolid*0.001; % km/sec uACS = g*iSPACS*0.001; % km/sec years = 10; dVAKM = 1.514; dVSK = 1.05*years*0.0107*(365.25/86.14); nFuelTanks = 2; pFuelBOL = 350*6895; pFuelEOL = 100*6895; for k = 1:10 % Solid rocket fuel %------------------ mPSolid = mSC*(1 - exp(-dVAKM/uSolid)); mFuel = (mSC - mPSolid)*(1 - exp(-dVSK/uACS)); % Reaction control subsystem dry mass %------------------------------------ mRC = (0.01 + 0.0115*sqrt(years))*mSC; % Solid motor dry mass %--------------------- mSolid = 0.07*mPSolid; % Structural mass %---------------- mST = 0.087*mSC; % Thermal control %---------------- mT = 0.032*mSC; % Attitude control %----------------- mAC = 65 + 0.022*(mSC - 700); mSC = mSA + mEL + mPayload + mPSolid + mSolid + mRC + mFuel + mST + mT + mAC + mAntenna; end fprintf(1,'\n---------------------- \n ComStar Spacecraft\n----------------------\n\n'); fprintf(1,'Separation mass = %12.2f kg\n',mSC); fprintf(1,'REA Fuel = %12.2f kg\n',mFuel); fprintf(1,'Payload = %12.2f kg\n',mPayload); fprintf(1,'Reaction Control = %12.2f kg\n',mRC); fprintf(1,'Antenna = %12.2f kg\n',mAntenna); fprintf(1,'Attitude Control = %12.2f kg\n',mAC); fprintf(1,'Solid Structure = %12.2f kg\n',mSolid); fprintf(1,'Solid Fuel = %12.2f kg\n',mPSolid); fprintf(1,'BOL Mass = %12.2f kg\n',mSC - mPSolid); % Volume calculations %-------------------- vFuel = mFuel/rhoFuel; solidLength = 0.6*widthCore; solidRadius = sqrt( ((mPSolid/rhoSolid)/solidLength)/pi ); fuelTankRadius = (3*(vFuel/nFuelTanks)/(4*pi))^(1/3); rFuelTank = fuelTankRadius + solidRadius; fprintf(1,'Solid Rocket Radius = %12.2f m\n',solidRadius); fprintf(1,'Fuel Tank Diameter = %12.2f m\n',2*fuelTankRadius); fprintf(1,'Fuel Tank Location = %12.2f m\n',rFuelTank); % Assume that the satellite has the following components %------------------------------------------------------- % 1 Solar arrays box % 2 North/south equipment bays box % 3 Fuel tanks sphere % 4 Solid rocket cylinder % 5 Structure hollow box % 6 Antennas disk % 7 Solid structure hollow cylinder % 1 2 2 4 7 2 3 5 2 2 6 % mSC = mSA + mEL + mPayload + mPSolid + mSolid + mRC + mFuel + mST + mT + mAC + mAntenna; mNSEquipment = mEL + mPayload + mRC + mT + mAC; % Get all of the inertias about their own centers of mass % z is the axis of symmetry for cylinders % Box inputs are x, y, z %-------------------------------------------------------- % Model as a 6 boxes with the length along y %------------------------------------------- iSA = Inertias( mSA/6,[widthCore lengthSAPanel thicknessSAPanel],'box' ); % 1 % Model as a 4 boxes %------------------- depthNSEq = widthCore/2 - sqrt(solidRadius^2-(widthCore/4)^2); iNSEq = Inertias( mNSEquipment/4,[0.4 0.4 1.6],'box' ); % 2 % Model as 2 spheres %------------------- iFuel = Inertias( mFuel/2, fuelTankRadius, 'sphere' ) ; % 3 % Model as a cylinder %------------------- iPSolid = Inertias( mPSolid, [solidRadius, solidLength,], 'cylinder' ); % 4 % Model as a hollow box (Aluminum 6061-T6) %----------------------------------------- thickness = mST/(6*widthCore^2)/rhoAL6061T6; iST = Inertias( mST, [widthCore widthCore widthCore, thickness], 'hollow box' ); % 5 % Model as 2 cylinders %--------------------- iAntenna = Inertias( mAntenna/2, [widthAntenna/2, widthAntenna/10], 'cylinder' ); % 6 % Model as a hollow cylinder %--------------------------- thickness = mSolid/(2*pi*solidRadius*solidLength*rhoAL6061T6); iSolid = Inertias( mSolid, [solidRadius, solidLength, thickness], 'hollow cylinder' ); % 7 fprintf(1,'Solar Panel Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iSA(1:3)); fprintf(1,'Equipment Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iNSEq(1:3)); fprintf(1,'Fuel Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iFuel(1:3)); fprintf(1,'Solid Fuel Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iPSolid(1:3)); fprintf(1,'Structure Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iST(1:3)); fprintf(1,'Antenna Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iAntenna(1:3)); fprintf(1,'Solid Structure Inertia = %12.2f %12.2f %12.2f kg-m^2\n',iSolid(1:3));
---------------------- ComStar Spacecraft ---------------------- Separation mass = 2046.53 kg REA Fuel = 235.79 kg Payload = 300.00 kg Reaction Control = 94.85 kg Antenna = 17.79 kg Attitude Control = 94.60 kg Solid Structure = 59.89 kg Solid Fuel = 855.60 kg BOL Mass = 1190.93 kg Solid Rocket Radius = 0.40 m Fuel Tank Diameter = 0.61 m Fuel Tank Location = 0.71 m Solar Panel Inertia = 1.82 1.82 3.65 kg-m^2 Equipment Inertia = 36.73 36.73 4.32 kg-m^2 Fuel Inertia = 4.36 4.36 4.36 kg-m^2 Solid Fuel Inertia = 100.24 100.24 69.06 kg-m^2 Structure Inertia = 126.22 126.22 126.22 kg-m^2 Antenna Inertia = 1.44 1.44 2.85 kg-m^2 Solid Structure Inertia = 9.33 9.33 9.46 kg-m^2
Locations with respect to the box center
%----------------------------------------- % Solar array panels [north, south] %---------------------------------- yBase = widthCore/2 + sABoom; ySAD = yBase + [0.5 1.5 2.5]*lengthSAPanel; rSAD = [zeros(1,6);-ySAD ySAD;zeros(1,6)]; ySAD = yBase + [0.5 1.5 2.5]*thicknessSAPanel; rSAU = [zeros(1,6);-ySAD ySAD;zeros(1,6)]; % North/south equipment %---------------------- rNSEq = [-0.8 0.8 -0.8 0.8;... -0.8 -0.8 0.8 0.8;... 0.0 0.0 0.0 0.0]; % Fuel tanks %----------- rFuel = [rFuelTank -rFuelTank;0 0;-.16 -.16]; % Solid Fuel and structure %------------------------- rPSolid = [0;0;(solidLength - widthCore)/2]; rSolid = rPSolid; % Structure %---------- rST = [0;0;0]; % Antennas %--------- rAntennaD = [antennaBoom + widthCore/2 -(antennaBoom + widthCore/2);0 0;0 0]; rAntennaU = [widthCore/2 -widthCore/2;0 0;0 0];
Transfer orbit mass properties
%-------------------------------- two = ones(1,2)/2; four = ones(1,4)/4; six = ones(1,6)/6; inr = [DupVect(iSA',6),iNSEq',iNSEq',iNSEq',iNSEq',iFuel',iFuel',iAntenna',iAntenna',iST',iSolid',iPSolid']; m = [mSA*six,mNSEquipment*four,mFuel*two,mAntenna*two,mST,mSolid,mPSolid]; r = [rSAU,rNSEq,rFuel,rAntennaU,rST,rSolid,rPSolid]; cD = [1;0; 0;0;1; 0;0;0;1]; cS = [1;0; 0;0;0;-1;0;1;0]; cA = [0;0;-1;0;1;0;1;0;0]; cN = [ 'North Inner Panel ';... 'North Middle Panel ';... 'North Outer Panel ';... 'South Inner Panel ';... 'South Middle Panel ';... 'South Outer Panel ';... 'Northwest Equipment';... 'Northeast Equipment';... 'Southwest Equipment';... 'Southeast Equipment';... 'East Fuel Tank ';... 'West Fuel Tanks ';... 'East Antenna ';... 'West Antenna ';... 'Structure ';... 'Solid Motor ';... 'Solid Motor Fuel ']; c = [cS,cS,cS,cS,cS,cS,cD,cD,cD,cD,cD,cD,cA,cA,cD,cD,cD]; fprintf(1,'\n------------------- \n Transfer Orbit\n-------------------\n'); MassProp( inr, m, r, 'mks', cN, c ); [inrTO, mTO, cMTO] = MassProp( inr, m, r, 'mks', cN, c );
------------------- Transfer Orbit ------------------- Inertias are [Ixx Iyy Izz Ixy Ixz Iyz] Component 1 North Inner Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.20 3.87 23.98 -0.00 0.00 2.22 kg-m^2 CM -0.0000 -1.6100 0.1616 m Mass 8.5467 kg Component 2 North Middle Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.75 3.87 24.53 -0.00 0.00 2.25 kg-m^2 CM -0.0000 -1.6300 0.1616 m Mass 8.5467 kg Component 3 North Outer Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 25.32 3.87 25.09 -0.00 0.00 2.28 kg-m^2 CM -0.0000 -1.6500 0.1616 m Mass 8.5467 kg Component 4 South Inner Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.20 3.87 23.98 0.00 0.00 -2.22 kg-m^2 CM -0.0000 1.6100 0.1616 m Mass 8.5467 kg Component 5 South Middle Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.75 3.87 24.53 0.00 0.00 -2.25 kg-m^2 CM -0.0000 1.6300 0.1616 m Mass 8.5467 kg Component 6 South Outer Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 25.32 3.87 25.09 0.00 0.00 -2.28 kg-m^2 CM -0.0000 1.6500 0.1616 m Mass 8.5467 kg Component 7 Northwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 144.68 144.68 211.75 -103.71 20.95 20.95 kg-m^2 CM -0.8000 -0.8000 0.1616 m Mass 162.0529 kg Component 8 Northeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 144.68 144.68 211.75 103.71 -20.95 20.95 kg-m^2 CM 0.8000 -0.8000 0.1616 m Mass 162.0529 kg Component 9 Southwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 144.68 144.68 211.75 103.71 20.95 -20.95 kg-m^2 CM -0.8000 0.8000 0.1616 m Mass 162.0529 kg Component 10 Southeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 144.68 144.68 211.75 -103.71 -20.95 -20.95 kg-m^2 CM 0.8000 0.8000 0.1616 m Mass 162.0529 kg Component 11 East Fuel Tank Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 4.36 63.12 63.12 0.00 -0.13 0.00 kg-m^2 CM 0.7060 -0.0000 0.0016 m Mass 117.8944 kg Component 12 West Fuel Tanks Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 4.36 63.12 63.12 -0.00 0.13 0.00 kg-m^2 CM -0.7060 -0.0000 0.0016 m Mass 117.8944 kg Component 13 East Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 3.08 7.37 7.14 0.00 -1.15 0.00 kg-m^2 CM 0.8000 -0.0000 0.1616 m Mass 8.8953 kg Component 14 West Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 3.08 7.37 7.14 -0.00 1.15 0.00 kg-m^2 CM -0.8000 -0.0000 0.1616 m Mass 8.8953 kg Component 15 Structure Inertia 126.22 126.22 126.22 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 130.87 130.87 126.22 -0.00 0.00 0.00 kg-m^2 CM -0.0000 -0.0000 0.1616 m Mass 177.9678 kg Component 16 Solid Motor Inertia 9.33 9.33 9.46 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 10.83 10.83 9.46 -0.00 -0.00 -0.00 kg-m^2 CM -0.0000 -0.0000 -0.1584 m Mass 59.8922 kg Component 17 Solid Motor Fuel Inertia 100.24 100.24 69.06 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 121.71 121.71 69.06 -0.00 -0.00 -0.00 kg-m^2 CM -0.0000 -0.0000 -0.1584 m Mass 855.6027 kg System Inertia 1005.55 -0.00 -0.00 -0.00 1006.32 -0.00 -3.408812e-16 System Inertia -0.00 1339.45 107.00 103.00 45.00 109.00 ^2 System CM 0.0000 0.0000 -0.1616 m System Mass 2046.5335 kg System Inertia in Principal Axes 1005.55 0.00 0.00 kg-m^2
Dual spin turn mass properties
Eliminate the solid motor fuel
%------------------------------- inr = inr(:,1:16); m = m(1:16); r = [rSAU,rNSEq,rFuel,rAntennaD,rST,rSolid]; c = [cS,cS,cS,cS,cS,cS,cD,cD,cD,cD,cD,cD,cA,cA,cD,cD]; cN = cN(1:16,:); fprintf(1,'\n------------------- \n Dual Spin Turn\n-------------------\n'); MassProp( inr, m, r, 'mks', cN, c ); inrDST = MassProp( inr, m, r, 'mks', cN, c );
------------------- Dual Spin Turn ------------------- Inertias are [Ixx Iyy Izz Ixy Ixz Iyz] Component 1 North Inner Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.00 3.67 23.98 -0.00 0.00 0.66 kg-m^2 CM -0.0000 -1.6100 0.0478 m Mass 8.5467 kg Component 2 North Middle Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.55 3.67 24.53 -0.00 0.00 0.67 kg-m^2 CM -0.0000 -1.6300 0.0478 m Mass 8.5467 kg Component 3 North Outer Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 25.11 3.67 25.09 -0.00 0.00 0.67 kg-m^2 CM -0.0000 -1.6500 0.0478 m Mass 8.5467 kg Component 4 South Inner Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.00 3.67 23.98 0.00 0.00 -0.66 kg-m^2 CM -0.0000 1.6100 0.0478 m Mass 8.5467 kg Component 5 South Middle Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 24.55 3.67 24.53 0.00 0.00 -0.67 kg-m^2 CM -0.0000 1.6300 0.0478 m Mass 8.5467 kg Component 6 South Outer Panel Inertia 1.82 3.65 1.82 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 25.11 3.67 25.09 0.00 0.00 -0.67 kg-m^2 CM -0.0000 1.6500 0.0478 m Mass 8.5467 kg Component 7 Northwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 -103.71 6.19 6.19 kg-m^2 CM -0.8000 -0.8000 0.0478 m Mass 162.0529 kg Component 8 Northeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 103.71 -6.19 6.19 kg-m^2 CM 0.8000 -0.8000 0.0478 m Mass 162.0529 kg Component 9 Southwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 103.71 6.19 -6.19 kg-m^2 CM -0.8000 0.8000 0.0478 m Mass 162.0529 kg Component 10 Southeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 -103.71 -6.19 -6.19 kg-m^2 CM 0.8000 0.8000 0.0478 m Mass 162.0529 kg Component 11 East Fuel Tank Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 5.85 64.61 63.12 0.00 9.34 -0.00 kg-m^2 CM 0.7060 -0.0000 -0.1122 m Mass 117.8944 kg Component 12 West Fuel Tanks Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 5.85 64.61 63.12 -0.00 -9.34 -0.00 kg-m^2 CM -0.7060 -0.0000 -0.1122 m Mass 117.8944 kg Component 13 East Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 2.87 52.70 52.68 0.00 -1.02 0.00 kg-m^2 CM 2.4000 -0.0000 0.0478 m Mass 8.8953 kg Component 14 West Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 2.87 52.70 52.68 -0.00 1.02 0.00 kg-m^2 CM -2.4000 -0.0000 0.0478 m Mass 8.8953 kg Component 15 Structure Inertia 126.22 126.22 126.22 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 126.63 126.63 126.22 -0.00 0.00 0.00 kg-m^2 CM -0.0000 -0.0000 0.0478 m Mass 177.9678 kg Component 16 Solid Motor Inertia 9.33 9.33 9.46 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 13.77 13.77 9.46 -0.00 -0.00 -0.00 kg-m^2 CM -0.0000 -0.0000 -0.2722 m Mass 59.8922 kg System Inertia 868.41 -0.00 -0.00 -0.00 960.26 -0.00 -3.515871e-17 System Inertia -0.00 1361.48 107.00 103.00 45.00 109.00 ^2 System CM 0.0000 0.0000 -0.0478 m System Mass 1190.9309 kg System Inertia in Principal Axes 868.41 0.00 0.00 kg-m^2
Mission orbit mass properties
Eliminate the solid motor fuel and rotate the antennas
%------------------------------------------------------- inr = inr(:,1:16); m = m(1:16); r = [rSAD,rNSEq,rFuel,rAntennaD,rST,rSolid]; c = [cD,cD,cD,cD,cD,cD,cD,cD,cD,cD,cD,cD,cA,cA,cD,cD]; cN = cN(1:16,:); fprintf(1,'\n------------------- \n Mission Orbit\n-------------------\n'); MassProp( inr, m, r, 'mks', cN, c ); [inrMO, mMO, cMMO] = MassProp( inr, m, r, 'mks', cN, c );
------------------- Mission Orbit ------------------- Inertias are [Ixx Iyy Izz Ixy Ixz Iyz] Component 1 North Inner Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 51.07 1.84 52.88 -0.00 0.00 0.98 kg-m^2 CM -0.0000 -2.4000 0.0478 m Mass 8.5467 kg Component 2 North Middle Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 138.59 1.84 140.39 -0.00 0.00 1.63 kg-m^2 CM -0.0000 -4.0000 0.0478 m Mass 8.5467 kg Component 3 North Outer Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 269.87 1.84 271.67 -0.00 0.00 2.29 kg-m^2 CM -0.0000 -5.6000 0.0478 m Mass 8.5467 kg Component 4 South Inner Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 51.07 1.84 52.88 0.00 0.00 -0.98 kg-m^2 CM -0.0000 2.4000 0.0478 m Mass 8.5467 kg Component 5 South Middle Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 138.59 1.84 140.39 0.00 0.00 -1.63 kg-m^2 CM -0.0000 4.0000 0.0478 m Mass 8.5467 kg Component 6 South Outer Panel Inertia 1.82 1.82 3.65 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 269.87 1.84 271.67 0.00 0.00 -2.29 kg-m^2 CM -0.0000 5.6000 0.0478 m Mass 8.5467 kg Component 7 Northwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 -103.71 6.19 6.19 kg-m^2 CM -0.8000 -0.8000 0.0478 m Mass 162.0529 kg Component 8 Northeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 103.71 -6.19 6.19 kg-m^2 CM 0.8000 -0.8000 0.0478 m Mass 162.0529 kg Component 9 Southwest Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 103.71 6.19 -6.19 kg-m^2 CM -0.8000 0.8000 0.0478 m Mass 162.0529 kg Component 10 Southeast Equipment Inertia 36.73 36.73 4.32 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 140.82 140.82 211.75 -103.71 -6.19 -6.19 kg-m^2 CM 0.8000 0.8000 0.0478 m Mass 162.0529 kg Component 11 East Fuel Tank Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 5.85 64.61 63.12 -0.00 9.34 0.00 kg-m^2 CM 0.7060 0.0000 -0.1122 m Mass 117.8944 kg Component 12 West Fuel Tanks Inertia 4.36 4.36 4.36 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 5.85 64.61 63.12 0.00 -9.34 0.00 kg-m^2 CM -0.7060 0.0000 -0.1122 m Mass 117.8944 kg Component 13 East Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 2.87 52.70 52.68 -0.00 -1.02 -0.00 kg-m^2 CM 2.4000 0.0000 0.0478 m Mass 8.8953 kg Component 14 West Antenna Inertia 2.85 1.44 1.44 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 2.87 52.70 52.68 0.00 1.02 -0.00 kg-m^2 CM -2.4000 0.0000 0.0478 m Mass 8.8953 kg Component 15 Structure Inertia 126.22 126.22 126.22 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 126.63 126.63 126.22 0.00 0.00 -0.00 kg-m^2 CM -0.0000 0.0000 0.0478 m Mass 177.9678 kg Component 16 Solid Motor Inertia 9.33 9.33 9.46 0.00 0.00 0.00 kg-m^2 Inertia wrt System CM 13.77 13.77 9.46 0.00 -0.00 0.00 kg-m^2 CM -0.0000 0.0000 -0.2722 m Mass 59.8922 kg System Inertia 1640.15 0.00 -0.00 0.00 949.33 0.00 -3.515871e-17 System Inertia 0.00 2144.15 107.00 103.00 45.00 109.00 ^2 System CM 0.0000 -0.0000 -0.0478 m System Mass 1190.9309 kg System Inertia in Principal Axes 1640.15 0.00 0.00 kg-m^2
Build the propulsion system
%---------------------------- [v, mP] = BDDesign( mFuel/nFuelTanks, 1000, 298, pFuelBOL, pFuelEOL ); fprintf(1,'\n------------------- \n Propulsion System\n-------------------\n'); vTank = [v v]; mHe = [mP mP]; mF = (mFuel/nFuelTanks)*ones(1,nFuelTanks); fprintf(1,'Fuel Tank Volume = %12.2f %12.2f m^3\n',vTank); fprintf(1,'Mass Helium = %12.2f %12.2f kg\n',mHe); fprintf(1,'Mass Fuel = %12.2f %12.2f kg\n',mF);
------------------- Propulsion System ------------------- Fuel Tank Volume = 0.17 0.17 m^3 Mass Helium = 0.18 0.18 kg Mass Fuel = 117.89 117.89 kg
Save important data
%-------------------- mDry = mTO - sum(mF) - mPSolid; mTODVFuel = mPSolid; cMAKM = rPSolid; inrAKM = iPSolid; mAKM = mPSolid; c = cd; p = fileparts(which(mfilename)); cd(p); save ComStarI inrTO mTO cMTO inrDST inrMO mMO cMMO mHe vTank mF mDry mTODVFuel mAKM cMAKM inrAKM fprintf(1,'\nData written to matfile ComStarI\n\n'); cd(c); %-------------------------------------- % PSS internal file version information %--------------------------------------
Data written to matfile ComStarI