differential equations - Animation of double pendulum

Sadly, I am a completely newbie. I am studying Physics and in our theoretical physics class we got the task to solve the double pendulum using Mathematica. We just got the program, but no introduction how to use it. So I am trying to animate the parametric plot. Any ideas?

sol = NDSolve[{
  2*phi1''[t] + phi2''[t]*Cos[phi1[t] - phi2[t]] + 
    phi2'[t]^(2)*Sin[phi1[t] - phi2[t]] + 2*9.81*Sin[phi1[t]] == 
  phi2''[t] + phi1''[t]*Cos[phi1[t] - phi2[t]] - 

    phi1'[t]^(2)*Sin[phi1[t] - phi2[t]] + 9.81*Sin[phi2[t]] == 0, 
  phi1[0] == Pi/2, phi2[0] == Pi, phi1'[0] == 0, phi2'[0] == 0}, 
  {phi1[t], phi2[t], t}, {t, 0, 10}] 

Plot[{phi1[t], phi2[t]} /. sol, {t, 0, 10}]

x1[t] := Evaluate[Sin[phi1[t]] /. sol]
y1[t] := Evaluate[-Cos[phi1[t]] /. sol]
x2[t] := Evaluate[Sin[phi1[t]] + Sin[phi2[t]] /. sol]
y2[t] := Evaluate[-(Cos[phi1[t]] + Cos[phi2[t]]) /. sol]


ParametricPlot[Evaluate[{{x1[t], y1[t]}, {x2[t], y2[t]}} /. sol], {t, 0, 10}]

Comments

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