Roman Czyba

Control Structure Impact on the Flying Performance of the Multi-Rotor VTOL Platform - Design, Analysis and Experimental Validation:

The aim of this research is to examine the different control strategies for the unmanned aerial vehicles (UAV). The control task is formulated as an angular stabilization of the four rotor platform, and also as a tracking problem of chosen state variables. The PID algorithm has been considered in three structures in respect of the optimal control signal applied to the actuators. For better performance of the quadrotor in hover mode the cascade control system has been proposed. The simulation results of attitude control with different PID controller architectures are presented, and confirm the effectiveness of the proposed control structure and theoretical expectations. Moreover, the design and the practical realization of the control architecture on the experimental aerial vehicle are described. The fast prototyping method together with Matlab/Simulink software and DAQ hardware are used for both evolution and validation of control algorithms. The capacity of the attitude stabilization system is important in the development process of more advanced functionality of autonomous flying vehicles; therefore it needs to be highlighted and taken into careful consideration.

Design of attitude control system for an UAV type-quadrotor based on dynamic contraction method

The problem of attitude stabilization and robust regulation of an indoor unmanned aerial vehicle, known as a quadrotor, is considered. This paper presents the design of continuous-time controller based on Dynamic Contraction Method. The control task is formulated as a tracking problem of Euler angles, where desired output transients are accomplished in spite of incomplete information about varying parameters of the system and external disturbances. The resulting controller is a combination of a low-order linear dynamical system and a subsystem which accomplishes an algorithm of quadrotor control. The experiment results for tracking a reference signal are presented, and confirm the effectiveness of the proposed method and theoretical expectations.

Data Fusion Algorithm for the Altitude and Vertical Speed Estimation of the VTOL Platform

An approach to the autonomous of the realization VTOL platform take-off and landing significantly simplifies the operator labor to control such device. At the same time, implementation of these control scenarios allows to perform these tasks under failure conditions (for example communication breakdowns). One condition of proper operation of the vertical movement control system is the ability to provide reliable information about the altitude of the controlled platform. In this paper one of the solutions for obtaining estimate of the altitude based on sensor data fusion is presented. Proposed scheme uses information obtained from pressure sensor, inertial measurement unit, ultrasonic sensor and GPS, all of these instruments are nowadays very often mounted on VTOL platforms.

Modeling and identification of electric propulsion system for multirotor unmanned aerial vehicle design

The propulsion system plays a key role in each unmanned aerial vehicle. Considering different multirotor platforms we may observe that mostly the dynamics and performance of the particular vehicle is strictly depended on the drive unit. In this paper we focus on the problem of modeling and identification of the propulsion system consisting of an electronic speed controller, electric brushless direct current motor and propeller. We propose a multiple-input and multiple-output nonlinear model of the propulsion unit based on the block oriented modeling with the static nonlinearities at the input and linear dynamical part at the output. Such model enhanced with the aerodynamics theory of a propeller should be suitable and detailed enough to provide the simulation, control algorithms prototyping and solution verification under the circumstances of designing the vertical take-off and landing unmanned platform.

Altitude estimation for the UAV's applications based on sensors fusion algorithm

Altitude measurement with a high reliability is a very difficult issue not because of the sensors complexity and requirements but due to the quality of the signals and fast changing environment conditions. In this paper we focus on the problem of the vertical movement measurements of the unmanned aerial vehicles and approach to the future control algorithms implementation. Two-sensors algorithm has been proposed on the basis of the data fusion from the pressure sensor and ultrasonic range finder.

DYNAMIC CONTRACTION METHOD APPROACH TO ROBUST LONGITUDINAL FLIGHT CONTROL UNDER AIRCRAFT PARAMETERS VARIATIONS

In the paper the design of an aircraft flight controller based on the Dynamic Contraction Method is presented. The control task is formulated as a tracking problem of aerodynamic state variables: velocity of flight and flight path angle, which are responsible for aircraft flight conditions in the longitudinal movement. The desired decoupled output transients are accomplished under aircraft parameters variations. The applied DCM method allows to create the expected outputs for non-linear and non- stationary objects in spite of incomplete information about varying parameters of the system and external disturbances. Simulations of selected maneuvers of F-16 fighter aircraft model confirm effectiveness of the design and theoretical expectations.

Development of co-axial Y6-Rotor UAV - design, mathematical modeling, rapid prototyping and experimental validation

This paper outlines development process of Y6-Rotor Micro UAV, which consists of concept of motion, modeling of the vehicle dynamics, rapid prototyping of the mechanics and finally practical realization of the VTOL. This paper presents a micro air vehicle designed to participate in the 2014 International Micro Air Vehicle Conference and Flight Competition (IMAV). Designed mechanical structure may also be referred to as a co-axial tri-rotor UAV, because has two rotors installed on each rotor axis. In order to improve the vehicle development it requires to derive accurate dynamics model enriched by empirical measurements of co-axial rotor performed on the test bench. Based on the theoretical considerations and previous stages of the development, the frame and mechanics of the vehicle has been designed and manufactured on the principle of rapid prototyping. Finally, flight tests performed on the real Y6-Rotor UAV show that the concept of flight mechanics and proposed control strategies are satisfactory at this early concept level.

Attitude and heading reference system based on 3D complementary filter

The paper presents the idea, design and performance evaluation of a low-cost Attitude and Heading Reference System (AHRS). It is based on an Inertial Measurement Unit (IMU), being a single sensor pack that provides all the raw data required to feed the designed filter. An extension of a complementary filter in form of feedback control system with PI controller, called 3D complementary filter provides attitude estimates in Euler angles representation. A developed algorithm of filtering and data fusion poses small computational requirements for the designed low-power embedded hardware. Test were performed based on the sensor model and next using a real IMU. Experimental results obtained by means of rapid prototyping of designed filtering algorithm in different operating states are presented and discussed.

Concept and realization of unmanned aerial system with different modes of operation

In this paper we describe the development process of unmanned aerial system, its mechanical components, electronics and software solutions. During the stage of design, we have formulated some necessary requirements for the multirotor vehicle and ground control station in order to build an optimal system which can be used for the reconnaissance missions. Platform is controlled by use of the ground control station (GCS) and has possibility of accomplishing video based observation tasks. In order to fulfill this requirement the on-board payload consists of mechanically stabilized camera augmented with machine vision algorithms to enable object tracking tasks. Novelty of the system are four modes of flight, which give full functionality of the developed UAV system. Designed ground control station is consisted not only of the application itself, but also a built-in dedicated components located inside the chassis, which together creates an advanced UAV system supporting the control and management of the flight. Mechanical part of quadrotor is designed to ensure its robustness while meeting objectives of minimizing weight of the platform. Finally the designed electronics allows for implementation of control and estimation algorithms without the needs for their excessive computational optimization.

Design and Control of a Single Tilt Tri-Rotor Aerial Vehicle

The aim of this paper is to outline a design process of an attitude control system for unmanned rotorcraft. This small-scale unmanned aerial robot’s concept is based on three rotors and one single tilt mechanism. Final design is consisted of mechanical construction, measurement system including navigation algorithm, as well as control structure and algorithm implementation at the last stage. It is important to underline that high attention was focused on the measurements filtering, estimation of the angular position, and in particular the practical aspects of the control implementation. Furthermore, a PID algorithm including various modified loop structures was studied. On the whole, it is worth to mention that the design, analysis and the validation tests were undertaken on the experimental aerial platform.