]> 2026-07-03T19:51:18+00:00 Configuration Flatness of Lagrangian Systems Underactuated by One Control 0 en Lagrangian control systems that are differentially flat with flat outputs that only depend on configuration variables are said to be configuration flat. We provide a complete characterisation of configuration flatness for systems with $n$ degrees of freedom and $n-1$ controls whose range of control forces only depends on configuration but not on velocity and whose Lagrangian has the form of kinetic energy minus potential. The method presented allows us to determine if such a system is configuration flat and, if so provides a constructive method for finding all possible configuration flat outputs. Our characterisation relates configuration flatness to Riemannian geometry. We illustrate the method by two examples. Muruhan Rathinam and Richard M. Murray 1996g <em>SIAM J. Control and Optimization</em>, 36(1):164-179 rm96-cdc Conference paper 2016-05-15T06:20:17Z 2457523.7640857 Configuration Flatness of Lagrangian Systems Underactuated by One Control Title 102 en Title