Interplanetary Missions

This MATLAB function was created to simulate Hooman transfer in the solar system.

function LunaOcampo_Pedro_Interplanetary(n,z) 

% This function provides the following data for interplanetary missions:

% 1. Total ?v for the Hohmann transfer to and back from the planet

% 2. Total Travel Time

% 3. Synodic Time Period

% 4. Wait time

% 5. Departure characteristics

%    a. Angular momentum, eccentricity of departure hyperbola from a ?z? km altitude circular 

%       parking orbit around earth

%    b. ?v from parking orbit to departure hyperbola

% 6. Arrival characteristics

%    a. Angular momentum, eccentricity of arrival hyperbola to get into an optimal circular 

%       orbit around the planet. If an optimal circular orbit does not exist, use a capture orbit 

%       with altitude ?z?.

%    b. ?v to get into the circular orbit and radius, time period of the capture orbit

%

% The labeling of the planets (n) is as follow:

% 1 Mercury

% 2 Venus

% 3 Earth

% 4 Mars

% 5 Jupiter

% 6 Saturn

% 7 Uranus

% 8 Neptune

%

% z is the altitude of the parking orbit around Earth

clc

n=4;z=650;

if n == 3 

    display(' ')

    error('Earth is not a valid destination!')

end

if n > 3

    n = n-1;

end

rade =  6378; %km

re = 149.6e6 ; %km

r = [57.91e6 108.2e6 227.9e6 778.6e6 1.433e9 2.872e9 4.495e9]; %km

rap = [2440 6052 3396 71490 60270 25560 24760]; %km

SR = 23.9345; %hrs

T1 = 365.256 * SR; %hrs

T2 = [87.97*SR 224.7*SR 1.881*T1 11.86*T1 29.46*T1 84.01*T1 164.8*T1]; %hrs

mu = 132712000000; %km^3/s^2

mup = [22030 324900 42828 126686000 37931000 5794000 6835100]; %km^3/s^2

mue = 398600; %km^3/s^2

dVa = abs(sqrt(2 * (mu / re - mu / (re + r(n)))) - sqrt(mu / re)); %kms/s

dVb = abs(sqrt(2 * (mu / r(n) - mu / (re + r(n)))) - sqrt(mu / r(n))); %kms/s

tdV = 2*(dVa + dVb); %kms/s

Tsyn = T1 * T2(n) / abs(T1 - T2(n)); %hrs

Tsynd = Tsyn / 24 ; %days

n1 = 2 * pi / T1; %rev/hr

n2 = 2 * pi / T2(n);  %rev/hr

a = (re + r(n)) / 2;

t12 = (pi * a^1.5) / sqrt(mu);%sec 

t12 = t12/3600;

t12d = t12/24; %days

phi_f = pi - n1 * t12;

N = 1;

if n1 > n2

    twait = (-2*phi_f - 2 * pi * N) / (n2 - n1);

    while twait <= 0

    twait = (-2*phi_f - 2 * pi * N) / (n2 - n1);

    N = N + 1;

    end

else

    twait = (-2*phi_f + 2 * pi * N) / (n2 - n1);

    while twait <= 0

    twait = -2*phi_f + 2 * pi * N / (n2 - n1);

    N = N + 1;

    end

end

twait = twait/24;

disp(' ')

disp('Interplanetary Trajectory from Earth to Planet')

disp('----------------------------------------------')

disp(' ')

fprintf('Total Delta V for the Hohmann transfer = %4.2f km/s ',tdV)

disp(' ')

fprintf('Total travel time = %4.2f days',t12d)

disp(' ')

fprintf('Synodic Period = %4.2f days',Tsynd)

disp(' ')

fprintf('Wait time = %4.2f days',twait)

disp(' ')

%%% Departure %%%

rc = rade + z;

Vinfd = dVa;

ed = 1 + (rc * Vinfd ^ 2) / mue;

hd = mue * sqrt(ed ^ 2 - 1) / Vinfd;

Vp = hd / rc;

Vc = sqrt(mue/rc);

dVd = abs(Vc - Vp);

disp(' ')

disp('Departure Characteristics')

disp('-------------------------')

disp(' ')

fprintf('Angular momentum of departure hyperbola = %4.2f km2/s2 ',hd)

disp(' ')

fprintf('Eccentricity of departure hyperbola = %4.2f ',ed)

disp(' ')

fprintf('Delta V = %4.2f km/s',dVd)

disp(' ')

%%% Arrival %%%

Vinfa = dVb;

ra = 2 * mup(n) / Vinfa^2; 

if ra < rap(n)

    ra = rap(n) + z;

end

ea = 1 + ra * Vinfa^2 / mup(n);

ha = mup(n) * sqrt(ea^2 - 1) / Vinfa;

Tpc = 2 * pi * ra ^ (1.5) / sqrt(mup(n));

dVaR = abs(sqrt(Vinfa^2 + 2 * mup(n) / ra) - sqrt(mup(n) / ra));

disp(' ')

disp('Arrival Characteristics')

disp('-------------------------')

disp(' ')

fprintf('Angular momentum of arrival hyperbola = %4.2f km2/s2 ',ha)

disp(' ')

fprintf('Eccentricity of arrival hyperbola = %4.2f ',ea)

disp(' ')

fprintf('Radius of optimal capture orbit = %4.2f km ',ra)

disp(' ')

fprintf('Time period of capture orbit = %4.2f km ',Tpc)

disp(' ')

fprintf('Delta V = %4.2f km/s',dVaR)

disp(' ')

end

The Sierpinski triangle implemented in MATLAB

Here is the code used to generate the triangle above:

n = 1000 %input('number of iterations? ')

m=2; xi=zeros(n);yi=zeros(n);

for m = 2:n

    r = randi([1 3]);

    

    switch r

        case 1

            xi(m)=.5*xi(m-1);

            yi(m)=.5*yi(m-1);

        case 2

            xi(m)=.5*xi(m-1)+.25;

            yi(m)=.5*yi(m-1)+sqrt(3)/4;

        case 3

            xi(m)=.5*xi(m-1)+.5;

            yi(m)=.5*yi(m-1);

    end

end

plot(xi,yi,'^')

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This method used tetrahedral meshing with global size of 1.34 in per element and absolute sag of 0.622 in.

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This is and electrical harness created in CATIA. It was made by using the Electrical Harness Assembly and Flattening workbenches.
The harness is composed of:
-GPS unit (top)
-PS-5a Connectors (bottom left and middle)
-Processing unit/fuse/diode (center)
-Switch (right)

The harness was then converted into a 2D drawing for easy assembly. 

E-mail me if you would like instructions on how to make these.

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Characteristic lines were found and plotted in Matlab for both a 15° conical and minimum length nozzles.

Temperature and pressure were also plotted

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This capsule is currently on a commercial resupply mission to the ISS

The dragon space capsule is designed to meet the Commercial Orbital Transport Services (COTS) requirements for transport to the International Space Station. The capsule’s main mission is to resupply the International Space Station (ISS).  Specific mission requirements were taken from NASA’s SSP 50700 document.  These requirements include handling capabilities, abort provisions, carrying capacities, and communication standards. The Dragon capsule has successfully flown two flights with a third planned. For the resupply mission, the dragon capsule is launched on a Falcon Nine launch vehicle designed and built by SpaceX. From launch to its 370km low earth orbit rendezvous with the international space station the mission is monitored at SpaceX’s mission center in Hawthorne, CA. The capsule’s payload includes: crew supplies, vehicle hardware, computer resources, spacewalk hardware, and Russian cargo. The dragon capsule consist of two articulated solar panels, four lithium polymer batteries, eighteen Draco thrusters, two compartment (one pressurized and one unpressurized) for cargo transport,  and onboard encryption/decryption systems. The capsule has a total volume of 25 m³, including the unpressurized trunk. It has two solar arrays that can generate up to 2000 W of power. With the stored propellant it can achieve 700 ,𝑚-𝑠. of Δv for its on orbit maneuvers.

External Flow on Aircraft

Drag force around the aircraft is depicted in the image below:

A cross sectional plane showing drag forces is also shown for the aircraft's mid plane:

 Flow vectors across the mid plane is shown below:

Solidworks

Solidworks Final Assembly of Welding Machine