= subs(VTdiff_t,symfunVariables,symVariables);

% Velocity - Alternative definition
dx_Alt_t    = VT_t*cos(PSI_t + ALPHAT_t);
dy_Alt_t    = VT_t*sin(PSI_t + ALPHAT_t);
dx_Alt      = subs(dx_Alt_t,symfunVariables,symVariables);
dy_Alt      = subs(dy_Alt_t,symfunVariables,symVariables);

% Acceleration - Alternative definition
ddx_Alt_t   = simplify(diff(dx_Alt_t,t));
ddy_Alt_t   = simplify(diff(dy_Alt_t,t));
ddx_Alt     = subs(ddx_Alt_t,symfunVariables,symVariables);
ddy_Alt     = subs(ddy_Alt_t,symfunVariab