I want to plot the position of Spherical pendulum.
First I tried to plot the simple pendulum:
DSolve[{y''[t] == -y[t], y[0] == Pi/2, y'[0] == 0}, y[t], t] (* {{y[t] -> 1/2 Pi Cos[t]}} *) then manipulate $t$
Manipulate[ ParametricPlot[{Sin[ 1/2 Pi Cos[t]], -Cos[1/2 Pi Cos[t]]}, {t, 0, n}, PlotRange -> 1,PlotStyle -> Red], {n, 0.1, 2Pi, 0.01}] I want to do same thing for spherical pendulum.
thereThese are differentialdifferential equations of the spherical pendulum page,3
sys := {\[Theta]''[t]θ''[t] == \[Phi]'[t]^2ϕ'[t]^2 Cos[\[Theta][t]]Cos[θ[t]] - g/l Sin[\[Theta][t]]Sin[θ[t]], \[Phi]''[t] ϕ''[t] == (-2 \[Phi]'[t]ϕ'[t] \[Theta]'[t]θ'[t] Cos[\[Theta][t]]Cos[θ[t]])/Sin[\[Theta][t]]Sin[θ[t]]} with initial condition
ic := {\[Theta][0]θ[0] == \[Pi]π/2, \[Theta]'[0]θ'[0] == 0, \[Phi][0]ϕ[0] == \[Pi]π/ 2, \[Phi]'[0]==1ϕ'[0] == 1} I tried:
sol = NDSolve[{\[Theta]''[t]θ''[t] == \[Phi]'[t]^2ϕ'[t]^2 Cos[\[Theta][t]]Cos[θ[t]] - g/l Sin[\[Theta][t]]Sin[θ[t]], \[Phi]''[ t] ϕ''[t] == (-2 \[Phi]'[t]ϕ'[t] \[Theta]'[t]θ'[t] Cos[\[Theta][t]]Cos[θ[t]])/ Sin[\[Theta][t]]Sin[θ[t]], \[Theta][0]θ[0] == \[Pi]π/2, \[Theta]'[0] == θ'[0] == 0, \[Phi][0]ϕ[0] == \[Pi]π/2, \[Phi]'[0]ϕ'[0] == 1} /. {g -> 9.81, l -> 1}, {\[Theta]θ, \[Phi]ϕ}, {t, 0, 10}] x[t_] := Evaluate[(Sin[\[Theta][t]]Sin[θ[t]] Cos[\[Phi][t]]Cos[ϕ[t]]) /. sol] y[t_] := Evaluate[(Sin[\[Theta][t]]Sin[θ[t]] Sin[\[Phi][t]]Sin[ϕ[t]]) /. sol] z[t_] := Evaluate[Cos[\[Theta]]Evaluate[Cos[θ] /. sol] ParametricPlot3D[{x[t], y[t], z[t]}, {\[Theta]θ, 0, 2 \[Pi]π}, {\[Phi]ϕ, -\[Pi]π, \[Pi]π}] but it doesn't work
