Symbolic system of odes
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Hey! So, I've been working on this physics problem where I face a system of four coupled differential equations which I can't seem to find the answer to
TT0 = 0; %initial release angle Theta
l0 = 1; %initial left line length (in meters)
m = 1;
M = 3;
R = 0.3;
g = 9.8;
mu = 0.5;
syms t Ti(t) Tx(t) TT(t) l(t);
ode1 = (M*g) - Tx == -M*(diff(l,t,2)+R*diff(TT,t,2));
ode2 = m*g*sin(TT) - Ti == m*(R*diff(TT,t,2)-l*(diff(TT,t))^2 + diff(l,t,2));
ode3 = m*g*cos(TT) == m*(R*(diff(TT,t))^2 + 2*diff(l,t)*diff(TT,t) + l*diff(TT,t,2));
ode4 = Tx == Ti*exp(mu*(pi/2 + TT));
odes = [ode1; ode2; ode3; ode4];
conds = [TT(0) == TT0; l(0) == l0;Ti(0) == 0; Tx(0) == M*g];
D = dsolve(odes,conds);
Here's the code I've written. There are four equations and four indeterminates but I get this error when I run the code:
"
Error using mupadengine/feval (line 163)
Cannot reduce to the square system because the number of equations differs from the number of indeterminates.
Error in dsolve>mupadDsolve (line 332)
T = feval(symengine,'symobj::dsolve',sys,x,options);
Error in dsolve (line 193)
sol = mupadDsolve(args, options);
Error in Untitled (line 16)
D = dsolve(odes,conds)
"
I've searched the internet and altered my code several times but it didn't seem to work. I'll highly appreciate any kind of help. Thanks.
5 Comments
darova
on 21 Apr 2019
Can you please show your equations in LaTeX or picture? Can't understand what is written there
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