Shock Absorber Design Through Matlab Iteration

[violentj]

Calculating area under graph from results of a for loop

Im currently designing a shock absorber for an aircraft undercarriage, i have input all the relevant information and formulas into Matlab and created an M file with a functioning for loop giving a graph. The problem I'm having now is that in order to work out the area under the graph that i get from the file i need a line of best fit, which cannot be plotted in MATLAB on a for loop with the use of hold on and hold off. The code i wrote is at the bottom of this postIs it possible to either put the results of the for loop into a vector to plot or failing that another way to get MATLAB to calculate the area under each graph.
The code i have created is below:

%Given Values

force=50620;
stat2ext=4/1;
comp2stat=3/1;
loadfactor=2.5;
staticP=7000000;

%Loads

load4ext=(1/(stat2ext))*(force*loadfactor)
load4stat=(force*loadfactor);
load4comp=comp2stat*(force*loadfactor);

%Pressures

p1=(1/(stat2ext))*staticP;
p2=staticP;
p3=comp2stat*staticP;

%Piston Area

areaP=load4stat/p2;
radiusP=sqrt(areaP/pi);

strokemax=0.5;

n1=1.1;
n2=1.35;

for stroke=0.1:0.01:0.5;
    
    %Displacement

    displacement=strokemax*areaP;

    v1=(displacement*p3)/(p3-p1);
    v3=v1-displacement;
    
   

    volumedown=stroke*areaP; 
    vn=v1-volumedown;
    pn= (p1*v1)/vn;
    pn1= (p1*v1^1.1)/vn;
    pn2= (p1*v1^1.35)/vn;
    
    load=areaP*pn;
    load1=areaP*pn1;
    load2=areaP*pn2;
    
    hold on
    
    plot(stroke,load)
    plot(stroke,load1)
    plot(stroke,load2)
    hold off

Thanks any suggestions or pointers would be greatly appreciated

 

[KataKoniK]

.
Thank you for sharing your code and the problem you are facing. It seems like you are trying to calculate the area under the graph generated by your for loop. There are a few ways to approach this problem, and I will provide two potential solutions for you.

One way to calculate the area under the graph is to use the trapezoidal rule. This involves dividing the graph into small trapezoids and calculating the area of each trapezoid. The sum of these areas will give you an estimate of the total area under the graph. To implement this in your code, you can create a vector to store the values of the load at each stroke, and then use the trapz() function in MATLAB to calculate the area under the graph. Here is an example of how you can modify your code to do this:

%Given Values

force=50620;
stat2ext=4/1;
comp2stat=3/1;
loadfactor=2.5;
staticP=7000000;

%Loads

load4ext=(1/(stat2ext))*(force*loadfactor)
load4stat=(force*loadfactor);
load4comp=comp2stat*(force*loadfactor);

%Pressures

p1=(1/(stat2ext))*staticP;
p2=staticP;
p3=comp2stat*staticP;

%Piston Area

areaP=load4stat/p2;
radiusP=sqrt(areaP/pi);

strokemax=0.5;

n1=1.1;
n2=1.35;

%Create a vector to store the values of load at each stroke
loads = [];

for stroke=0.1:0.01:0.5;

%Displacement

displacement=strokemax*areaP;

v1=(displacement*p3)/(p3-p1);
v3=v1-displacement;



volumedown=stroke*areaP;
vn=v1-volumedown;
pn= (p1*v1)/vn;
pn1= (p1*v1^1.1)/vn;
pn2= (p1*v1^1.35)/vn;

load=areaP*pn;
load1=areaP*pn1;
load2=areaP*pn2;

%Add the value of load at