• Configuration controllability of simple mechanical control systems 

      Lewis, Andrew D.; Murray, Richard M. (Society for Industrial and Applied Mathematics, 1995)
      In this paper we present a definition of "configuration controllability" for mechanical systems whose Lagrangian is kinetic energy with respect to a Riemannian metric minus potential energy. A computable test for this ...
    • Decompositions of control systems on manifolds with an affine connection 

      Lewis, Andrew D.; Murray, Richard M. (North-Holland, 1997)
      In this letter we present a decomposition for control systems whose drift vector field is the geodesic spray associated with an affine connection. With the geometric insight gained with this decomposition, we are able to ...
    • Nonholonomic mechanics and locomotion: the snakeboard example 

      Lewis, Andrew D.; Ostrowski, James P.; Burdick, Joel W.; Murray, Richard M. (IEEE, 1994)
      Analysis and simulations are performed for a simplified model of a commercially available variant on the skateboard, known as the Snakeboard.1 Although the model exhibits basic gait patterns seen in a large number of ...
    • Variational principles for constrained systems: theory and experiment 

      Lewis, Andrew D.; Murray, Richard M. (1994)
      In this paper we present two methods, the nonholonomic method and the vakonomic method, for deriving equations of motion for a mechanical system with constraints. The resulting equations are compared. Results are also ...