+ // Inertias
+ double get_Mass() const { return mass; }
+ double get_I_xx() const { return i_xx; }
+ double get_I_yy() const { return i_yy; }
+ double get_I_zz() const { return i_zz; }
+ double get_I_xz() const { return i_xz; }
+
+ void _set_Inertias( double m, double xx, double yy, double zz, double xz)
+ {
+ mass = m;
+ i_xx = xx;
+ i_yy = yy;
+ i_zz = zz;
+ i_xz = xz;
+ }