Passivity-based nonlinear control strategies for strict feedback form systems

This paper presents a tracking algorithm for the control of nonlinear dynamic systems represented in Strict Feedback Form. The construction of the stabilizing algorithm is given using Passivity-based arguments which result in a Passivity-Based Controller (PBC). Also shown are simulations demonstrating the performance of the suggested approach. This paper also shows a direct comparison with the most popular control strategy for Strict Feedback Form Systems: Integrator Backstepping. It is shown that although Integrator Backstepping has several advantages, most notably flexibility in designing output feedback and adaptive approaches, there do exist important situations that favor the PBC. When the model structure is poorly known, the PBC contains diagnostic effects allowing it to systematically pinpoint parts of the model containing inaccuracies. Moreover, the PBC can be simpler to implement than the Backstepping algorithms in the non-adaptive, state feedback case.