Grzegorz Kopecki

Algorithms of Measurement System for a Micro UAV

The article presents a measurement system for a micro UAV designed at the Department of Avionics and Control Systems of Rzeszów University of Technology. Since the project is based on earlier projects, e.g.[[[[1[[[1, the introduction begins with their short presentation [they are mentioned in the introduction firs. Then, the current project is discussed. The major objective of the project is to create a miniature autopilot cooperating with navigation units, data transmission units and measurement units. The system is based on Polish technological solutions. The autopilot is designed as a single unit, however the system is open and it allows you to use different elements. The system development is also possible. In-flight testing will be realized with the use of two unmanned flying platforms equipped with an electrical engine and a piston engine. The total mass of the platforms is 5 kg and 25 kg respectively. The article presents the structure of the control and navigation system and then, the structure of the measurement system. The measurement units consist of a GPS receiver, an attitude and heading reference system (AHRS) and an air data computer (ADC). Similar configuration is used in other micro UAV solutions, such as Micropilot or Kestrel. Then, algorithms of the measurement system are described. Navigation is based on GPS data with a DGPS (Differential GPS) advanced module. If the measurement information is complete, GPS data are used to correct measurements from other units. The system estimates wind disturbances and calculates accelerometers errors. In the case of missing GPS signals implementation of low-cost sensors may lead to significant measurement errors, and hence navigation only by means of the INS is impossible. In such a case, navigation is realized with the use of an inertial navigation system (INS), the magnetic heading measurement and ADC. AHRS unit algorithms use quaternion algebra for attitude calculation. For correction, complementary filtering is implemented [, [. The correction signal for the attitude (pitch and roll angles) is calculated with the use of acceleration measurements. Measurements of accelerations and yaw rates are used for the correction switching mechanism, since in dynamic states signals calculated from accelerations cannot be used for correction. Heading is corrected by means of magnetic heading measurement. ADC algorithms are based on typical aerodynamic dependences.

Problems of Monitoring in the Fly-by-Wire System for Small Aircraft

The article presents problems of monitoring a Fly-by-Wire control system mounted on the board of experimental general aviation aircraft. The system is being designed at the Rzeszow University of Technology, Department of Avionics and Control. The idea of the system is to make a pilot-friendly small general aviation aircraft. First flight test results are very promising. The data transmission system is realized with the use of the CAN bus. Every system element has its own microprocessor and sends data to the bus. The data recording was made with the use of movable PC with specialized software. The monitoring system records all data at a hard disc and makes visualization. Parameters of the control system were observed and used by the system operator during flight tests. Two different transmission protocols were tested. The idea of the first protocol, called CANres, is to connect three different data from one module of FBW system equipment. The second tested protocol was CANaerospace. The idea of this protocol is to send one data in one frame. Problems of data acquisition in both protocols, as well as the description of practical problems concerned with software and transmission protocol that appeared during tests are presented in the article.

Integration of optical measurement methods with flight parameter measurement systems

During the AIM (advanced in-flight measurement techniques) and AIM2 projects, innovative modern techniques were developed. The purpose of the AIM project was to develop optical measurement techniques dedicated for flight tests. Such methods give information about aircraft elements deformation, thermal loads or pressure distribution, etc. In AIM2 the development of optical methods for flight testing was continued. In particular, this project aimed at the development of methods that could be easily applied in flight tests in an industrial setting. Another equally important task was to guarantee the synchronization of the classical measuring system with cameras. The PW-6U glider used in flight tests was provided by the Rzeszow University of Technology. The glider had all the equipment necessary for testing the IPCT (image pattern correlation technique) and IRT (infrared thermometry) methods. Additionally, equipment adequate for the measurement of typical flight parameters, registration and analysis has been developed. This article describes the designed system, as well as presenting the systems application during flight tests. Additionally, the results obtained in flight tests show certain limitations of the IRT method as applied.

Flight Simulator as a Tool for Flight Control System Synthesis and Handling Qualities Research

At the Department of Avionics and Control Systems problems of aeronautical control systems have been dealt with for years. Several different kinds of aeronautical control systems have been designed, prototyped and tested. These control systems are intended for general aviation aircraft and unmanned aircraft. During all research projects computer simulations and laboratory tests were made. However, since in some cases such tests were insufficient, in-flight tests were conducted leading to a series of reliable results. The in-flight tests were made with the use of M-20 Mewa aircraft (autopilot for a GA aircraft) and PZL-110 Koliber aircraft (control system for UAV and indirect flight control system for a GA aircraft). Nevertheless, in-flight testing is very expensive and problematic. To avoid some problems appearing during in-flight tests and their preparation, a simulator – which is normally used for professional pilot training – can be used. The Aviation Training Center of the Rzeszów University of Technology possesses the ALSIM AL-200 MCC flight simulator. We have started preparing this simulator for the research. It is possible to control the simulated aircraft with the use of an external control system. The solution proposed enables testing the aircraft control algorithms, indirect control laws (e.g. control laws modifying handling qualities), as well as testing and assessment of the students’ pilotage skills. Moreover, the solution makes it possible to conduct tests connected with aircraft control, crew management, crew cooperation and flight safety. The simulator allows us to test dangerous situations, which – because of safety reasons – is impossible during in-flight testing. This paper presents modifications to the simulator’s hardware and additional software, which enable the described research.

The Selected Innovative Solutions in UAV Control Systems Technologies

The paper presents selected original solutions concerning UAV control systems technologies. The paper does not describe general theories and global technical solutions used in UAV’s technologies. It presents some tricks created and developed at Rzeszow University of Technology. Presented solutions have been developed and implemented into real control systems. They main goal is to improve control precision and increase system functionality. Results presented in this paper have been collected during real flight tests of different classes of UAVs.

Data acquisition system for PW-6U in flight boundary layer mapping

Purpose This paper aims to describe an idea for an integration process and tests of flight parameters measurement system, which supports infrared thermography (IRT) boundary layer mapping. Design/methodology/approach The study of flow changes in the boundary layer with the use of IRT requires registration of the thermal images of the selected area of a wing or the fuselage, as well as synchronous recording of flight parameters. These tasks were realized by the supplementary measurement system mounted on the PW-6U glider. Two examples of the determination of the laminar-turbulent transition areas on the left wing of a PW-6U glider are also presented in the paper. Findings Optical methods can be used in several research areas, for example, aerodynamics and strength analysis. For instance, the measurement of the infrared radiation from surfaces with the use of IRT can be used for the measurement, with high accuracy, of surface temperature distribution. Moreover, the thermography is used for the analysis of the boundary layer. Performed in-flight experiments confirm the possibility of practical usage of the IRT method even on the board of a glider. Practical implications The use of optical methods will, in many cases, be less expensive than assembly of an additional measurement and data acquisition systems. Implementation of optical methods for industrial purposes has many advantages, and, hence, they will probably become very common in the future. Originality/value The study introduces advanced measurement and visualization techniques in general aviation.

Control computers diagnostics for UAV flight control system

Purpose The purpose of this paper is to present the topic of control computers diagnostics. They are part of an unmanned aerial vehicle (UAV) control system implemented in a modified version of MP-2 Czajka aircraft. Design/methodology/approach The algorithms were designed as a basic version of the diagnostic system. The system is open and will be developed. Findings First results show that the diagnostic system works properly. The system is easy for implementation and burdens the control computers only insignificantly. Research limitations/implications The system presented can detect only computers out of work. In its present version, it cannot detect such errors as improper calculations of control signals. After first in-flight testing, the system will be further developed. Practical implications The diagnostic system is implemented in an UAV technology demonstrator. Originality/value The designed system is the part of an UAV control system, designed for ground observation. Such technology demonstrator and flying laboratory enable different type of research in the area of aviation.

Review of Chosen Control Algorithms Used for Small UAV Control

In this article review of chosen control algorithms used for small UAV at Department of Control Systems of Rzeszów University of Technology and their properties is presented. At first, control laws based on modified PID algorithms are described. The example of modification is the use of double differentiation in the algorithm. Proposed modifications improve control quality. Next, model following LQR algorithms is introduced. Implementation of that algorithm improves control quality in the flight at trajectory. In the algorithm presented integration between desired trajectory and plant trajectory is introduced as an additional state.Another algorithm which is presented is sliding mode control algorithm as an example of robust control. It allows you to control plane in event of a fault. Appropriate selection of sliding surface ensures the stability of the system and good quality control under normal operating conditions and enables flight in the event of non-critical damage. To improve the quality control in emergency mode, the parameters of the sliding surface during flight can be modified. The last presented algorithm is model reference adaptive controller. The adaptation mechanism is derived from second Lyapunov method. It also enables control in the case of chosen faults. An example presented in the article is realized for roll angle control. In the case of control surface fault (e.g. aileron or rudder), the algorithm enables aircraft control. In that case control surface fault is treated as an uncertainty of model used.