This problem can be found here.
using NLOptControl
nothing # hide
n=define(numStates=2,numControls=1,X0=[0.,1],XF=[0.,-1.],XL=[0.,NaN],XU=[1/9,NaN]);
nothing # hide
dx=[:(x2[j]),:(u1[j])]
dynamics!(n,dx)
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configure!(n;(:Nck=>[100]),(:finalTimeDV=>true));
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obj=integrate!(n,:(0.5*u1[j]^2));
@NLobjective(n.ocp.mdl,Min,obj);
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optimize!(n);
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allPlots(n)