This paper presents the design of digital controller for longitudinal aircraft model based on the Dynamic Contraction Method. The control task is formulated as a tracking problem of velocity and flight path angle, where decoupled output transients are accomplished in spite of incomplete information about varying parameters of the system and external disturbances. The design of digital controller based on the pseudo-continuous approach is presented, where the digital controller is the result of continuous-time controller discretization. A resulting output feedback controller has a simple form of a combination of low-order linear dynamical systems and a matrix whose entries depend nonlinearly on certain known process variables. Simulation results for an aircraft model confirm theoretical expectations.

In the article, a device for measuring the parameters of the rotational movement of the auger for dewatering solid waste is proposed based on the analysis of signal processing methods and measurement of physical quantities. It can be used in the development of high-performance special vehicles for transporting waste as the main link in the structure of machines for the collection and primary processing of solid waste. The structural scheme of the means and block diagram of the microcontroller control program algorithm for implementation of the device for measuring the parameters of the rotational motion are proposed. The main technical characteristics of the proposed means are given. The results of experimental tests for measuring the parameters of rotational motion are shown. The results of experimental studies, which are given in the work, confirmed the reliability of the measured parameters.

In the paper we propose a fractional-piecewise-constant-order PID controller and discuss the stability and robustness of a closed loop system. In stability analysis we use the transform method and include the Nyquist-like criteria. Simulations for designed controllers are performed for the second-order plant with a delay.

Software power protection tester implemented in a real-time operating system (RTOS) might replace the conventional testing setups in IEC 61850 protection systems. This paper describes an open power protection testing platform. Linux RT capabilities related to runtime environment for such a tester are examined and OS latency sources are identified and evaluated. An algorithm for a multithreaded tester operation is proposed, including Sampled Values (SV) publisher, GOOSE input/output and time synchronization. SV and GOOSE services implemented in RT Linux environment are evaluated in accordance with IEC 61850‒5 transfer time requirements. Linux PTP time synchronization service of two similar systems controlling its electrical ports is evaluated in different synchronization scenarios. The developed tester is compared to an equivalent conventional setup during the test of IED over-current function. The conducted tests show that the Linux implementation of power protection tester in the case of scheduler latency, time synchronization accuracy and transfer time all meet the requirements of IEC 61850.