Showing papers by "Isabela Roxana Birs published in 2017"

Discrete-time implementation and experimental validation of a fractional order PD controller for vibration suppression in airplane wings

Abstract: Vibrations in airplane wings have a negative impact on the quality and safety of a flight. For this reason, active vibration suppression techniques are of extreme importance. In this paper, a smart beam is used as a simulator for the airplane wings and a fractional order PD controller is designed for active vibration mitigation. To implement the ideal fractional order controller on the smart beam unit, its digital approximation is required. In this paper, a new continuous-to-discrete-time operator is used to obtain the discrete-time approximation of the ideal fractional order PD controller. The efficiency and flexibility, as well as some guidelines for using this new operator, are given. The numerical examples show that high accuracy of approximation is obtained and that the proposed method can be considered as a suitable solution for obtaining the digital approximation of fractional order controllers. The experimental results demonstrate that the designed controller can significantly improve the vibration suppression in smart beams.

An experimental nanomedical platform for controller validation on targeted drug delivery

Abstract: Targeted drug delivery is a focus point in recent advances in the nanomedical field due to its many advantages such as decreased side effects, faster action and better drug absorption with less substance used. The paper presents an experimental platform that simulates the circulatory system: the passing of blood from arteries to smaller blood vessels, while also capturing the non-Newtonian characteristic of the blood. The targeted drug delivery is ensured by a scalable submersible equipped with various sensors and actuators such that the real-time position of the submersible can be determined and controlled in the circulatory system. The purpose of the presented work is to provide a solid foundation for experimental modeling of the interaction between the submersible and non-Newtonian fluids and for validating different control strategies suitable for velocity control. The experimental setup takes into account the real life difficulties of targeted drug delivery.

Comparative analysis and exprimental results of advanced control strategies for vibration suppression in aircraft wings

Abstract: The smart beam is widely used as a means of studying the dynamics and active vibration suppression possibilities in aircraft wings. The advantages obtained through this approach are numerous, among them being aircraft stability and manoeuvrability, turbulence immunity, passenger safety and reduced fatigue damage. The paper presents the tuning of two controllers: Linear Quadratic Regulator and Fractional Order Proportional Derivative controller. The active vibration control methods were tested on a smart beam, vibrations being mitigated through piezoelectric patches. The obtained experimental results are compared in terms of settling time and control effort, experimentally proving that both types of controllers can be successfully used to reduce oscillations. The analysis in this paper provides for a necessary premise regarding the tuning of a fractional order enhanced Linear Quadratic Regulator, by combining the advantages of both control strategies.

An optimal fractional order controller for vibration attenuation

Abstract: Unwanted vibrations may cause severe damage and may endanger the lives of passengers on board of an airplane. In the last years, there has been an increased focus on the study of active vibration techniques. A viable possibility to actively control the vibration of an airplane wing is by using piezoelectric actuators. The paper presents a novel tuning procedure of a fractional order Proportional Derivative controller based on three points of the magnitude Bode diagram. The eloquence of the controller is experimentally validated on an experimental setup consisting of an aluminum beam that replicates an airplane wing.

Fractional order modeling and control of a smart beam

Abstract: Smart beams are one of the most frequently used means of studying vibrations in airplane wings. Their mathematical models have been so far solely based on classical approaches that ultimately involve integer order transfer functions. In this paper, a different approach towards modeling such smart beams is considered, an approach that is based on fractional calculus. In this way, a fractional order model of the smart beam is obtained, which is able to better capture the dynamics of the system. Based on this novel fractional order model, a fractional order PDμ controller is then tuned according to a set of three design constraints. This design leads to a closed loop system that exhibits a much smaller resonant peak compared to the uncompensated smart beam system. Experimental results are provided, considering both passive and active control responses of the smart beam, showing that a significant improvement of the closed loop behavior is obtained using the designed controller.