I'm not able to figure out what is going on with this system. My other systems are getting solved but not this one. Can anyone help me figure this one out?
rho = 0.289018; % [lb/in^3]; density of material
Sy = 30000; % [psi]; yield strength of material
E = 27992280; % [psi]; Youngs modulus of material
V = 2158.689078; % [in^3]; volume of ENTIRE structure with solid legs, from SolidWorks
L = 118.25; % [in]; length of box structure, perpendicular to truck pulling force
w = 26; % [in]; width of box structure
l = 36; % [in]; height of legs
h = 9.1; % [in]; height of box structure only
Dl = 4; % [in]; outer diameter of legs
W = rho*V; % [lbf]; weight load of structure (conservative, treats legs as solid)
P = 16*20*2 + W; % [lbf]; centroidal load due to weight and PTDs w/ safety factor
Ry = 1250; % [lbf]; rxn in dir of pulling
Mx1 = (2500*2)*(l+h)/4 - P*w/8;My1 = P*L/8;MR1 = sqrt(Mx1^2 + My1^2); %total moment
syms I A t1x tau sigz R1 R3 %Leg 1, x-max
%Leg 1, x-maxeqns = [I == (pi/64)*(Dl^4 - (Dl-2*t1x)^4), A == (pi/4)*(Dl^2 - (Dl-2*t1x)^2), ... tau == (3/2)*Ry/A, sigz == R1/A + My1*(Dl/2)/I, R1 == (P/2)-R3, ... R3 == P/2 - (P*(w/2) + 5000*(l+h))/(2*w), Sy == sqrt(sigz^2 + 3*tau^2)];S1 = vpasolve(eqns, [I,A,t1x,tau,sigz,R1,R3]);
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