These types of equations of motion are based on so-called redundant coordinates, because the equations use more coordinates than degrees of freedom of the underlying system. The generalized coordinates are denoted by q , the mass matrix is represented by M ( q ) which may depend on the generalized coordinates. C represents the constraint conditions and the matrix C q (sometimes termed the Jacobian) is the derivative of the constraint conditions with respect to the coordinates. This matrix is used to apply constraint forces λ λ to the according equations of the bodies. The components of the vector λ λ are also denoted as Lagrange multipliers. In a rigid body, possible coordinates could be split into two parts,