This study presents an algorithm for starry sky image synthesis intended for debugging and calibrating star detectors. The proposed algorithm generates images of the starry sky as they would be observed by a star detector mounted on an aircraft or a maritime vessel, taking into account the platform’s geographic coordinates, attitude, and velocity. The simulation incorporates the detector’s spatial resolution and spectral sensitivity, with particular emphasis on infrared (IR) radiation in J, H, and K photometric bands. An algorithm implemented in MATLAB was used to produce synthetic starry sky images, which were subsequently processed using star identification and attitude determination methods in order to ensure that simulated images can be used in practice. Next, a comparative analysis of attitude estimation errors was conducted for several commonly employed attitude determination algorithms, providing quantitative insights into their performance under simulated observational conditions.

This paper presents a prototype of an autonomous hydrochemical monitoring system developed for large freshwater aquaculture facilities, directly addressing the need for smart monitoring in Agriculture 4.0. The proposed solution employs low-power sensor nodes based on commercially available components and long-range LoRaWAN communication to achieve continuous, scalable, and energy-efficient water quality monitoring. Each sensor module performs on-board signal preprocessing, including anomaly detection and short-term forecasting of key hydrochemical parameters. An ecological pond dynamics model incorporating an Extended Kalman Filter is used to fuse heterogeneous sensor data with predictive estimates, thus increasing measurement reliability. High-level data analysis, long-term storage, and cross-site comparison are performed on the server side. This integration enables adaptive tracking of environmental variations, supports early detection of hazardous trends associated with fish mortality risks, and allows one to explain and justify the reasoning behind every recommended corrective action. The performance of the forecasting and filtering algorithms is evaluated, and key system characteristics—including measurement accuracy, power consumption, and scalability—are discussed. Preliminary tests of the system prototype have shown that it can predict the dissolved oxygen level with $RMSE$ = 0.104 mg/L even with a minimum set of sensors. The results demonstrate that the proposed conceptual design of the system can be used as a base for real-time monitoring and predictive assessment of hydrochemical conditions in aquaculture environments.

Background. When monitoring vibration of rotating machines, especially heavy ones, problems with cables of transducers often emerge. Those cables are usually long, heavy and prone to damage. Objective. The purpose of the paper is to develop a wireless vibration transducer, which is free of those problems, on the base of MEMS accelerometer. Sensor developed should provide low power consumption, linear frequency response at least in 10…1000 Hz range, calculate vibration RMS and detect machine condition based on it. Methods. Develop wireless sensor design based on 8-bit MCU. Develop method of MEMS frequency response correction, based on spectral analysis. Compare sensor developed with industrial piezoelectric ones. Results. Transducer developed can be used instead of the industrial piezoelectric vibration transducers. Moreover, MEMS-based transducer allows one to move basic machine condition detection process from the high–level system to transducer level. That, in turn, allows one to reduce network traffic and simplify condition monitoring system as a whole. Conclusions. MEMS-based wireless vibration transducer for condition monitoring is developed. Tests conducted showed that the transducer developed is well–behaved and its precision is comparable to one of industrial piezoelectric transducers.

Development of wireless vibration transducer based on MEMS accelerometer

One of key errors of the classic interference-type fiber-optic goniometer is the thermo-optical zero shift. Its caused by the non-uniform change of temperature of different fiber sections in the loop under the influence of temperature; as a result of that, counter-rotating waves get different phase incursions during stretching of fiber in the loop, thus creating thermo-optical zero shift (Shupe effect). Difference of the phase incursions of counter-rotating waves is the bigger the higher speed of fiber length change is, and the higher difference of delay time of those waves. The current study is focused on the modeling of influence of the Shupe effect on on the precision of the fiber optic goniometer. The key features of the goniometer mentioned are use of the copper coil carcass and compound with high thermal conductivity (use of nanotubes is desired). Different coil winding types (simple, dipole quadrupole, modified quadrupole, bifilar, octupole) are considered from the point of view of minimizing the thermo-optical zero shift under self-heating and influence of the ambient temperature changes. Analysis is based on the transient thermal analysis of finite element model of the goniometer performed in ANSYS environment with subsequent data import and integration of phase incursion, calculated based on temperature data, along the fiber length. Study results show that best results during self-heating gives the use of quadrupole winding, at that goniometer's zero shift changes insignificantly (about 0.08°, compared to 1,35° for the simple winding). Change of ambient temperature for a given design has almost no influence on the zero shift, as device is heated uniformly. One should note that as during modeling not all factors could be taken into account, the result obtained should be checked and qualified during FOG tests.

Three-dimensional scanning is a relatively new technology that allows one to obtain a digital three-dimensional model of an object with the help of an electronic device and computer technology. Three-dimensional scanning is used in many fields: architecture, mechanical engineering, aviation, medicine, culture and art, education. The use of three-dimensional scanning for part quality control allows one to significantly reduce the required volume of measurements, since main geometric parameters of the part (linear and angular dimensions) and even deviations of the shape and location can be determined from the data of three-dimensional modeling without the use of complex and time-consuming measurement methods. This article is devoted to the evaluation of the quality of 3D scanning of machine parts and the possibility of using of their models, created by 3D scanning, in the quality control of parts. The conducted analysis shows that the deviation of the grid points of the scanned part from the approximating primitives significantly depends on the shape of the part. Details of a simple form are scanned with the best results (with minimal deviations); scanning holes, gear teeth, threads and similar features requires the skills of the personnel involved and additional processing. The quality of scanning also depends significantly on the type of scanner used. However, the given results confirm that, provided a high-quality and accurate scanner is used, practical use of 3D scanning for the quality control of parts is possible.