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In the era of rapid advancements in manned and unmanned aviation and robotics, there is a need for high-performance, robust attitude control of highly maneuverable fixed-wing aircraft, both manned and unmanned (UAVs). This paper presents an extension to research on spacecraft attitude control. The article extends existing concepts and applies them to the control problem of aircraft operating in Earth’s atmosphere. First, a general concept of quaternions is presented. Next, the attitude controller’s architecture is discussed. The controller synthesis is described using quaternion algebra. The quaternion-based attitude controller is then compared with a classical Euler-based attitude controller. The methodology for comparison and performance evaluation of both controllers is described. Lastly, the results of the simulations and a comparison of the two controllers are presented and discussed. The presented control scheme outperforms classical methods based on Euler angles, particularly at the aircraft’s high pitch and roll angles.

The article describes the progress of construction and research works on ultrasound tomography. The devices allow for non-invasive measurements of various objects using ultrasonic low and high-frequency transducers. The first constructions were made in a dispersed system with active measurement probes using 40 kHz converters. The next constructions were centralized into one measurement system where the measurement probes were connected separately. As a result, the measuring range of the supported ultrasonic transducers with 300 kHz, 400 kHz and 1 MHz has been extended. Apart from transmission and reflection tomography, the latest designs allow for controlling the ultrasound beam (beamforming) and support transducers up to 5 MHz.