Mechanical feedback linearization of single-input mechanical control systems
Marcin Nowicki, Witold Respondek
TL;DR
This paper develops mechanical feedback linearization (MF-linearization) for single-input mechanical control systems, aiming to preserve the mechanical structure (configurations and velocities) during linearization. It establishes geometric necessary-and-sufficient conditions, expressed via the nested distributions $\mathcal{E}^i$ and compatibility constraints on covariant derivatives and Christoffel symbols, that determine when an MS can be MF-linearized to a controllable linear mechanical system. The main results prove MF-equivalence for $n\ge3$ (with MF1–MF4) and a specialized $n=2$ case (MF1'–MF5'), and are illustrated through three examples, including an inertia wheel pendulum and the TORA3 system, highlighting that MF-linearizable systems form a proper subset of F-linearizable ones. The work emphasizes preserving physical interpretation and sensor requirements, and sets the stage for future comparisons between MF- and classical F-linearization and for broader mechanical control design techniques.
Abstract
We present a new type of feedback linearization that is tailored for mechanical control systems. We call it a mechanical feedback linearization. Its basic feature is preservation of the mechanical structure of the system. For mechanical systems with a scalar control, we formulate necessary and sufficient conditions that are verifiable using differentiations and algebraic operations only. We illustrate our results with several examples.
