3 research outputs found
Global stabilisation of the PVTOL aircraft with lateral force coupling and bounded inputs
"This work is devoted to prove that the nonlinear control scheme previously proposed by Zavala-Río, Fantoni and Lozano for the global stabilisation of the planar vertical take-off and landing (PVTOL) aircraft with bounded inputs neglecting the lateral force coupling is robust with respect to the parameter characterising such a lateral force coupling, ϵ, as long as such a parameter takes small enough values. In other words, global stabilisation is achieved even if ϵ > 0, provided that such a parameter be sufficiently small. As far as the authors are aware, such a property has not been proved in other existing control schemes when the value of ϵ is not known. The presented methodology is based on the use of embedded saturation functions. Furthermore, experimental results of the control algorithm implemented on a real prototype are presented.
Predictor-Feedback Stabilization of Multi-Input Nonlinear Systems
We develop a predictor-feedback control design for multi-input nonlinear
systems with distinct input delays, of arbitrary length, in each individual
input channel. Due to the fact that different input signals reach the plant at
different time instants, the key design challenge, which we resolve, is the
construction of the predictors of the plant's state over distinct prediction
horizons such that the corresponding input delays are compensated. Global
asymptotic stability of the closed-loop system is established by utilizing
arguments based on Lyapunov functionals or estimates on solutions. We
specialize our methodology to linear systems for which the predictor-feedback
control laws are available explicitly and for which global exponential
stability is achievable. A detailed example is provided dealing with the
stabilization of the nonholonomic unicycle, subject to two different input
delays affecting the speed and turning rate, for the illustration of our
methodology.Comment: Submitted to IEEE Transactions on Automatic Control on May 19 201