We present a new output control approach for a linear plant with input delay and an unknown multiharmonic disturbance acting on the input and the output. To solve this problem, we combine the well-known predictor feedback approach with the state observer and adaptive scheme that identifies the frequency of the disturbance. Compared to the existing approaches, the structure of our adaptive schem...

1 *Assistant Professor, Electrical and Computer Engineering Department, Kharazmi University, Tehran, Iran,: [email protected], 2 .Associated Professor, Faculty of Electrical Engineering, Tarbiat Modares University, Tehran, Iran. 3 .Assistant Professor, Faculty of Electrical Engineering, Tarbiat Modares University, Tehran, Iran Abstract Non-fragile H ∞ observer design is the main problem of th...

In this paper, an adaptive sliding mode disturbance observer is designed to counteract the actively. By designing laws, assumptions on are relaxed in proposed observer, its first derivative upper bound considered be unknown. Based output feedback controller constructed for continuous-time linear systems with unknown external disturbance. The incorporates only system information and has less cha...

The Robust control problem for time varying uncertain linear systems with non-commensurate time varying state and control delays is studied. By solving LMIs we design robust controller, via an observer-based output feedback, which stabilizes the system and reduces the effect of the disturbance input on the controlled output for all admissible uncertainties. The results depend on the time deriva...

One of the major challenges in robotic arms is to diagnosis sensor fault. To address this challenge, this paper presents an LPV approach. Initially, the dynamics of a two-link manipulator is modelled with a polytopic linear parameter varying structure and then by using a descriptor system approach and a robust design of a suitable unknown input observer by means of pole placement method along w...

The dynamic properties and non-linear control of the pneumatic muscle actuator (PMA) were investigated in this study for use in a specially designed hand rehabilitation device. The phenomenological model of PMA was established in the lower pressure range applicable for hand rehabilitation. The experimental results show that PMA’s characteristics can be approximated by piecewise functions. In or...

Robust control of nonlinear systems with disturbances and uncertainties is addressed in this paper using disturbance observer based control technique. In this framework, the “disturbance” is a generalized concept, which may include external disturbances, unmodeled dynamics, and system parameter perturbations. The existing disturbance observer based control (DOBC) methods were only applicable fo...

Naphthalene dioxygenase (NDO) from Ralstonia sp. strain U2 has not been reported to oxidize nitroaromatic compounds. Here, saturation mutagenesis of NDO at position F350 of the alpha-subunit (NagAc) created variant F350T that produced 3-methyl-4-nitrocatechol from 2,6-dinitrotoluene (26DNT), that released nitrite from 23DNT sixfold faster than wild-type NDO, and that produced 3-amino-4-methyl-5...