maihudson:

Mathematica code:

A[N_, t_] :=
 Graphics[
   Table[
    Rotate[
     Table[
     {GrayLevel[Abs[j - 1]], EdgeForm[GrayLevel[1]], 
      Disk[{0, 0}, N - n + j, {Pi, 0}]},
     {j, 1, 0, -1}],
    Pi*(N - n + 1) (1 + Sin[t*Pi - Pi/2]), {0, 0}],
   {n, 0, N, 1}],
 PlotRange -> N + 1.5, ImageSize -> 500]

Manipulate[G[15,t],{t,0,1}]