Wing rock phenomenon is an undesired motion appears in high angles of attack where a rolling in the aircraft in positive and negative roll angles with specified amplitude and frequency is occurred. In this paper two adaptive controllers suggested to control the rolling dynamics under wing rock phenomenon for a delta wing aircraft with presence of disturbance. Disturbance was considered as unmat...

Wing rock is a highly nonlinear phenomenon in which the aircraft undergoes limit cycle roll oscillations at high angles of attack. A single neuron control scheme for suppression of wing rock of slender delta wings is presented. The effectiveness of the control scheme is demonstrated through software simulation and real-time control experiments in a wind tunnel on a 80 swept back wing. The suppr...

The wing rock phenomenon is a high angle of attack aerodynamic motion manifested by limit cycle roll oscillations. Experimental studies reveal that direct control and manipulation of leading edge vortices, through the use of ‘blowing’ techniques is effective in the suppression of wing rock. This paper presents the design of a robust controller for the experimental implementation of one such ‘bl...

Wing rock is a highly nonlinear phenomenon when the aircraft suffers undesired roll-dominated oscillatory at high angle of attack (AOA). Considering the strong nonlinear and unsteady aerodynamic characteristics, an uncertain multi-input and multi-output (MIMO) nonlinear wing rock model is studied, and system uncertainties, unsteady aerodynamic disturbances and external disturbances are consider...

LE leading edge Transonic free-to-roll and static wind tunnel tests for four military aircraft – the AV-8B, the F/A-18C, the pre-production F/A-18E, and the F-16C – have been analyzed. These tests were conducted in the NASA Langley 16-Foot Transonic Tunnel as a part of the NASA/Navy/Air Force Abrupt Wing Stall Program. The objectives were to evaluate the utility of the freeto-roll test techniqu...

W ing rock is an oscillatory ro lling motion which arises at high angles of attack in aircraft with highly-swept wings. In the present paper, a method to suppress wing rock through sliding mode control is proposed. Sliding mode control is designed to min imize together roll angle error and command input through a cost function. The procedure is performed on a wing-only analytical model, the con...

In this paper, robust UDE-based linear control strategy is developed for a class of second-order nonlinear uncertain systems with disturbances. After revealing the control structure and performing stability analysis, the robust control strategy is used to suppress wing rock motion. The approach is based on the uncertainty and disturbance estimator,which calculates and robustly cancels system un...

The wing rock motion is mathematically described by a nonlinear differential equation with coefficients varying with angle of attack. In this paper, a neural-network-based adaptive control system is developed for the wing rock motion control. The adaptive controller comprises a neural network controller and a compensation controller. The neural network controller using a recurrent neural networ...

In 3-D analyses of rock slopes there’re can be numerous sliding paths a long a coplanar nonpersistent discontinuity with a known strike. This paper describes an approach for the determination of a most probable sliding path. For this particular study, several blocks of gypsum with the dimensions of 15×15×15 cm containing coplanar non-persistent open joints were fabricated. The models have vario...

Transmission to new hosts is a fundamental challenge for parasites. Some species meet this challenge by hitchhiking on other, more mobile parasite species, a behaviour known as phoresis. For example, feather-feeding lice that parasitise birds disperse to new hosts by hitchhiking on parasitic louse flies, which fly between individual birds. Oddly, however, some species of feather lice do not eng...