No. 2

Improving the accuracy of the ADC using projective transformations

The article is devoted to methods for improving the accuracy of ADCs based on the use of projective measurements. The methods take into account the integral nonlinearity of the transformation. A criterion is used to evaluate the efficiency of the ADC measurement transformation.

Keywords: projective measurement, ADC, accuracy, efficiency criterion.

Measurement system for monitoring the value of small magnetic fields. Part 1. Intelligent sensor

The article discusses the principles of constructing a sensor for measuring small magnetic field values (from 20 ⋅10–9 T to 60⋅10–9 T) that arise as a result of pipeline defects in transport gas networks. The problem of separating the values of the magnetic field of a defect and background magnetic fields (of the Earth, pipeline and other objects that form external effects on measuring transducers) is solved. A method for compensating interfering fields, the structure of an intelligent sensor, its operating algorithm, and a measurement technique are proposed.

Keywords: measuring system, pipeline, defect, magnetic field, magnetic induction, compensation method, intelligent sensor.

Application of vision technology in the task of automatic landing of a quadrocopter on a moving platform

This paper proposes an approach to enable a vision-based multirotor quadrocopter-class unmanned aerial vehicle (UAV) to automatically detect, pursue, and land on an unmanned ground vehicle (UGV). To solve the above problems, ArUco fiducial markers are used to estimate the relative position of the UAV and the UGV by processing RGB images acquired by a monocular camera mounted on board the UAV. The resulting relative position estimate is used in the trajectory planner and flight controller to generate the necessary control actions that modify the UAV's flight speed. Using a cascade loop strategy, these setpoints are then passed to the UAV autopilot for an internal control loop. Algorithms, software and testing have been developed and tested using ROS, Gazebo, Ardupilot and MATLAB simulation environments.

Keywords: UAV, UGV, quadcopter, automatic landing, technical vision, landing platform, artificial landmarks.

Investigation of the features of processing and displaying the results of automated ultrasonic quality control of additive manufacturing products

The paper analyzes the features of the formation and registration of an ultrasonic signal. As a result of the analysis, it was found that for a product with acceptable porosity, ultrasonic testing can be used to determine the presence of large defects, as well as to detect microcracks, inclusions, pores. These types of defects can be detected using the echo method. An algorithm for processing and displaying the results of automated ultrasonic quality control of additive manufacturing products using neural network algorithms has been developed. The developed neural network model allows detecting defects with a probability of at least 0,7.

Keywords: automated non-destructive testing, additive manufacturing, neural network algorithms, defect detection.

Temperature stabilization module of fiber Bragg grating

This paper describes the problem of temperature stabilization of the central wavelength of the peak of a fiber Bragg lattice. To solve this problem, a temperature stabilization module based on the ESP-WROOM-32 DevKit v1 board was developed, which is able to stabilize and maintain the value of the central wavelength. The paper describes an experiment showing the correct operation of the stabilization module. Conclusions were drawn about the application and further modernization.

Keywords: FBG, fiber Bragg grating, temperature, stabilization, ESP 32, central wavelength.

Practical aspects of computer modeling application for determining the nature of physical processes of magnetic fields operation

In this publication the method of analyzing magnetic emitters used in medicine in a computer environment from the point of view of studying magnetic parameters that arise when a signal is applied to them with a certain frequency is considered. After obtaining electromagnetic values, a comparative characterization of three magnetic emitters was made for their further development in medicine. The purpose of this work was to justify the use of three magnetic emitters of different shapes and sizes in analyzing the parameters of the pulsed magnetic field for medical purposes for further procedures. In the course of this work the main parameters of magnetic emitters such as magnetic induction, current density and other parameters were determined. Also considered the very stage of analysis of magnetic emitters in the Comsol Multiphysics environment with the use of some elements of computer modeling. It is established, parameters of magnetic radiators are in various dependencies – linear, exponential and others. The geometry of magnetic emitters used in writing a scientific paper is presented. In conclusion, ideas of further use of the described magnetic emitters in science are offered due to the processing of results to determine new ways of realization and development of magnetic fields.

Keywords: magnetotherapy, computer modeling, Comsol Multiphysics, induction, magnetic emitters.

Development of a low-frequency charge-discharge method for controlling architectural electrochromic windows

This article presents an innovative method of low-frequency charge-discharge control of architectural electrochromic devices. The approach proposed by the authors allows to effectively solve the problem of the edge effect, i.e. uneven distribution of current density over the active surface of large-sized electrochromic products. The new method provides a significant reduction in the electro-optical edge effect: 47 times compared to the galvanostatic control method and 13.7 times compared to the pulse-width modulation mode of the supply voltage.

Keywords: electrochromic devices, edge effect, low-frequency charge-discharge control, control methods.

Investigation of microhybrid composites by a spectrophotometer operating in the field of far ultraviolet

The use of microhybrid composites based on solid-state matrices in the scientific research base is important, therefore, the study of this material at the electronic level in the atom is promising and relevant. The purpose of this work was to identify the spectral characteristics of microhybrid composites in the far ultraviolet region. The paper sets the goal, the task of the study and defines the method and object of the study. The appearance and main technical parameters of the experimental spectrophotometric installation are given. Spectral dependences of the absorption coefficient on the wavelength in the range from 200 nm to 300 nm are obtained. It was revealed that the materials do not differ much in optical parameters, therefore, the latest microhybrid materials of domestic production are not inferior to foreign ones.

Keywords: spectrophotometer, far ultraviolet spectroscopy, measuring channel, light beam, wavelength, absorption coefficient, microgibritic material.