Janusz Narkiewicz

Aerodynamic Loads on Airfoil with Trailing-Edge Flap Pitching with Different Frequencies

Unsteady aerodynamic loads on NACA 0012 airfoil with a trailing-edge flap were measured in wind tunnel and calculated from a simple theoretical model. The airfoil model of 0.18 m chord length used in wind-tunnel test was oscillating in pitch about an axis located at 35% chord length from the airfoil leading edge. The length of trailingedge flap was 22.6% of airfoil chord. The flap was also deflecting harmonically, but with frequency different from airfoil pitching motion. The influence of phase delay between airfoil angle of incidence and flap deflection at the beginning of the motion was considered. The theoretical method used for calculation of unsteady airfoil loads is based on two-dimensional, inviscid, incompressible flow model at subsonic Mach numbers. The expressions for unsteady aerodynamic loads calculations on the airfoil and on the flap were obtained in a closed form using distribution of flow velocity potential along the airfoil chord and along the flap length. Lift and aerodynamic moment measured in the wind tunnel were compared with results of calculations. The correlation between experimental and theoretical results is adequate.

Autopilot Supported by Nonlinear Model Following Reconfigurable Flight Control System

The reconfigurable flight control system was developed, applying a nonlinear aircraft model following control algorithm to support the autopilot. The model of a six degrees of freedom airplane with nonlinear aerodynamics and second-order dynamics of control system actuators was supplemented by aircraft autopilot based on classical control laws. The autopilot commands the aircraft in normal operations. In failure cases, the control system reconfiguration is performed using comparison of control external loads on damaged aircraft with loads in undamaged aircraft operation. Fuzzy logic method produces the control signals preventing the consequences of failures. The objective of reconfiguration is to continue the performed flight, including maneuvers, and, if this is not possible, to obtain the steady flight. The aircraft simulation model was tested for consistency with the expected flight performance. The selected autopilot functions were validated and reconfiguration applied in selected cases of failures. T...

Innovative, reconfigurable simulator of mobile robots to support anti-crisis operations

The paper presents innovative, reconfigurable simulator of mobile robots included in anti-crisis operations system. The simulator development is a part of the PROTEUS project. Along the whole anti-crisis system is developed, the simulator of mobile robots is constructed. Majority of the simulators developed worldwide are intended for specific vehicles and used for various applications of particular robots. This approach does not satisfy developers from Poland because the anti-crisis operations system has an open architecture and allows to introduce different mobile robots into action. In the paper the requirements and architecture of the simulator are described. Its integration with training system of all parts of anti-crisis operations is discussed. The paper shows the novelty of the solution (both in hardware and software).

Identification of EMA Dynamic Model

The electromechanical actuator (EMA) model is presented with the methods for identifying its design parameters. The actuator is part of the system for flap deployment on the commercial transport airplane. The differential equations with the feedback control describe behaviour of the actuator deflection. For parameter identification the Maximum Likelihood (ML) method with two minimization algorithms: linearized Gauss-Newton and Levenberg-Marquardt is applied. Both approaches were effective, while tested on hypothetical data.

Quadrotor Dynamics and Control for Precise Handling

The paper contains part of the results of a research done at the Warsaw University of Technology (WUT) devoted to modeling and control system design for a quadrotor UAV. The quadrotor lift, propulsion and control loads are produced by four identical rotors, performance of which strongly depends on flight conditions. The quadrotor angular rates result in not identical flow through each of the rotors due to their not coaxial configuration which may cause disturbances of a flight path. The development of a complex dynamic model and a control law enhancement method for a quadrotor is presented in this paper. The novel approach to control system development led to increase in quadrotor handling precision, due to compensates disturbances of the flight path, which makes a quadrotor more capable to operate in a confined space.

Optimal selection of UAV for ground target tracking

A method for selecting a UAV for the tracking and following of a ground mobile vehicle is considered, which leads to optimizing operation of a UAV fleet. The UAV is selected from an available fleet taking into account fleet distribution in airspace, performance of fleet members, and the prospective motion of a ground object. The UAV fleet members have various flying qualities, so assigning the aircraft for tracking is based on optimization process. The tracking algorithm with embedded target trajectory prediction is presented. Simulation results associated with the proposed algorithm demonstrated improved efficiencies associated with various ground vehicle trajectories.

Aircraft Status Supervision System Concept

AbstractA system for supervision of aircraft status was developed, modeled and simulated. The system assesses overall aircraft status based on data available from external (out-of-aircraft) and int...

Non-GPS Navigation System for Criminalistic Investigation on Mobile Robot

In the paper we describe visual odometry algorithm for monocular camera. It is developed for use on a mobile robot involved in criminal investigation conducted by Polish police forces. FAST keypoints with ORB descriptors are used as input to the motion estimation. Concept of pose graph is implemented in order to improve accuracy of the results obtained. The algorithm was evaluated on a 400 m long outdoor dataset included in KITTI Benchmark (18.41 % position error) as well as on a short dataset collected indoors in one of the offices at our University (5.34 % position error). Detailed discussion of the results is presented together with the guidance for further development of the method.

Application of Genetic Algorithms for Identification of Simulated Systems

A new system identification method (TSGA) based on Genetic Algorithms for system simulation is presented. The method is performed in two steps (S1 and S2). In each step of the method, a new approach to the population definition and identification process are applied for identification of parameters of system model. The simulated model with identified parameters is used for simulations of the system behavior. The method is suitable to linear as well as nonlinear models.

Optimal Object Location by a Fleet of Various UAVs

Locate task optimization methodology and preliminary results for a various UAV fleet are presented in the article. In the main part of the paper, aircraft and sensor models are described with constraints imposed on areas covered by each aircraft. The models and operational area are discretised for implementing a Mixed Integer Linear Programming (MILP) algorithm with the objective to minimize the mission time. A two step optimization processes is described: 1) assign search areas to particular aircraft; 2) calculate trajectories for each vehicle.