Path: Interplanetary/Optimization
% Compute optimal trajectory
The cost function is the total mass of the vehicle. This version allows the
"switch" time to be a variable, with one time step before the switch and
another after.
Specific combinations of parameters may not provide a solution. fmincon will
fail to converge in that case. The power is calculated from the thrust,
exhaust velocity, and thrust efficiency. The engine mass is calculated from
the specific power.
P = 0.5 T*uE/eta
mE = P/sigma
The total mass is
m0 = mP + (1 + f)*mF + mE
where mP is the mass of the payload, f is the fuel structural fraction, and mE
is the mass of the engine.
Type PlanarHelioOptimalSlidingTime for a demo to Mars
--------------------------------------------------------------------------
Form:
d0 = PlanarHelioOptimalSlidingTime
[phi, thrust, t, data] = PlanarHelioOptimalSlidingTime( d, maxIter, iterDisp )
--------------------------------------------------------------------------
------
Inputs
------
d (.) Data structure
.uE Exhaust velocity
.r0 Initial radius
.rF Final radius
.mu Gravitational parameter of the sun
.f Fuel structural fraction
.tF Final time (s)
.eta Thrust efficiency
.sigma Specific power (W/kg)
.maxThrust Maximum allowable thrust (N)
maxIter (1,1) Maximum number of iterations
-------
Outputs
-------
phi (1,n) Thrust angle (rad)
t (1,n) Times (s)
thrust (1,1) Thrust (N)
data (.) Results data structure
.p (1,1) Power (W)
.mD (1,1) Dry mass (kg)
.mF (1,1) Fuel mass (kg)
.dV (1,1) Delta-V (km/s)
.dF (1,1) Final distance achieved (km)
.vF (1,1) Final velocity achieved (km/s)
--------------------------------------------------------------------------
See also SimulatePlanarHelioTrajectory
--------------------------------------------------------------------------
Interplanetary: Optimization/RHS2DCylindricalOrbit Interplanetary: Optimization/SimulatePlanarHelioTrajectory StraightLine: ConstantAccel/ThrustElectric StraightLine: ConstantThrust/DVConstantThrust Common: Database/Constant Math: Integration/RK4 Math: Linear/Mag
Back to the Interplanetary Module page