MATLAB Question:

You plan to launch a rocket that has the parameters provided below, you are to write a program that will calculate flight trajectory without wind resistance. Your program is to utilize the finite difference approach for calculating trajectory parameters every 0.01 seconds until it hits the ground (negative elevation).

clear all close all

%Initial Conditions t(1)= 0.0; dt= 0.01; h(1)= 1; vel(1)= 0; mcase= 16; mfuel(1)= 134; BR= 4.8; fthrust(1)= 1560; Agravity=-9.81; vel(1)=0; Atotal(1)=0; ke(1)=0; pe(1)=0; te(1)=0;

i=1;

while h(i)>0 t(i+1)=t(i)+dt; mfuel(i+1)=max((mfuel(i)-(BR*dt))); mtotal(i+1)=mcase+mfuel(i+1); fthrust(i+1)=fthrust(i)*(mfuel(i+1)); Athrust(i+1)=((fthrust(i+1))/(mtotal(i+1))); Atotal(i+1)=Athrust(i+1)+Agravity; vel(i+1)=vel(i)+((Atotal(i+1)+Atotal(i))/2)*dt; h(i+1)=h(i)+((vel(i+1)+vel(i))/2); ke(i+1)=1/2*mtotal(i)*vel(i)^2; pe(i+1)=mtotal(i)*(Agravity)*h(i); te(i+1)=pe(i)+ke(i); i=i+1; end

subplot(2,2,1) plot(t,Atotal); grid title('Time vs. Acceleration') xlabel('Time (s)') ylabel('Acceleration (m/s^2)') pause(2)

subplot(2,2,2) plot(t,vel); grid title('Time vs. Velocity') xlabel('Time (s)') ylabel('Velocity (m/s)') pause(2)

subplot(2,2,3) plot(t,h); grid title('Time vs. Altitude') xlabel('Time (s)') ylabel('Altitude (m)') pause(2)

subplot(2,2,4) plot(t,mtotal); grid title('Time vs. Total Mass') xlabel('Time (s)') ylabel('Total Mass (kg)') pause(2)

No matter what I change in the code I keep getting these four graphs, please help.

Also, I do not think this is meant to be done with a for loop.

These are what the graphs are meant to look like:

x 10 Pfme vs. Acceleration x 10303 Time vs. Velocity 2 2 0.5 0.5 1.5 Time (s) Time vs. Total Mass Time (s) 10302 Time vs. Altitude 15 150 E 10 3 100 D 50 0.5 10 20 Time (s) Time (s) Velocity: No Wind Resistance Acceleration: No Wind Resistance 100 6 50 100 150 0 100 150 0 time (seconds) Altitude: No Wind Resistance time (seconds) Total Mass: No Wind Resistance 150 10000 0 50 0 100 time (seconds) 150 0 150 100 time (seconds) 0