Nonlinear tracking controller design for steer-by-wire automotive systems

In this paper, a continuous time-varying tracking controller is designed for a steer-by-wire system in a automotive vehicle to ensure that the vehicles position/orientation follow that of a reference generator. The tracking error is globally and exponentially forced to a neighborhood about zero that can be made arbitrarily small (i.e., globally, uniformly and ultimately boundedness). The result is facilitated by transforming the system into a flat input-state system and then fusing a filtered tracking error transformation with the dynamic oscillator design. We also illustrate that the proposed tracking controller yields a globally, uniformly and ultimately bounded result for the regulation problem.