 ddy PSI dPSI ddPSI

% Alternative velocity related variables: Side slip angle and speed
% Alternative variables (symfun)
syms ALPHAT_t(t) VT_t(t)
% Alternative variables and time derivatives (sym)
syms VT ALPHAT dVT dALPHAT

% Inputs 
syms deltaf deltar FxF FxR
% Tire lateral forces
syms FyF FyR
% Vehicle parameters 
syms a b mT IT

%% Generalized coordinates and time derivatives
% <html>
% <p>The generalized coordinates are</p>
% <p>
% \begin{eqnarray}
% \nonumber q_1 &=& x     \\
% \nonumber q_2 &=& y   