Second derivative of function park(theta) with respect to time.
function der2_park extends Modelica.Icons.Function; input SI.Angle theta "transformation angle"; input SI.AngularFrequency omega "d/dt theta"; input SI.AngularAcceleration omega_dot "d/dt omega"; output Real[3, 3] der2_P "d2/dt2 park"; end der2_park;