Alexander Sutor

Wireless light emitters (WLEs) powered by an alternating magnetic field can be used to illuminate photoreactors internally. State-of-the-art WLEs have a diameter of 10 mm and consist of an iron-core receiver coil, a capacitor and a light-emitting diode (LED). Since the iron-core inductor restricts the available design space, particularly for the integration of a second LED, it shall be replaced by a PCB coil. This work proposes a multilayer PCB coil design that satisfies the size constraint while achieving comparable performance. The design features an area-efficient trace layout that maximizes the effective conductor length and inductive coupling. A generalized design methodology is introduced, allowing the concept to be adapted to different coil diameters, layer counts, and manufacturing constraints. Evaluation by FEM simulations and measurements of fabricated PCB coils shows that the proposed multilayer PCB approach is a promising alternative to conventional iron-core receiver coils for compact WLEs.

Mitigating climate change and preserving biodiversity are both crucial to maintain Earth’s habitability for future generations. While wind energy turbines are urgently needed for sustainable power generation, the threat they pose to their surrounding ecosystems must be closely investigated. Especially birds and bats are highly prone to die by colliding with wind turbines or due to barotrauma caused by flying in the direct proximity of the rotor blades. Therefore, to develop a measurement setup which reliably counts impacts on rotor blades is indispensable to establish effective preventive measures. In this work we developed a test setup designed to resemble the conditions of a bat or bird strike to perform preliminary experimentes. Furthermore, we investigated four different sensors, comprising a piezoelectric microphone, as well as a piezoelectric and two capacitive accelerometers, in regard of their feasibility for the intended use case by comparing signal-to-noise ratios and cross-correlations. Material- and structure-related parameters such as wave propagation velocities and damping factors have also been evaluated to obtain initial insights into their behavior. Since the impact onset detection algorithm is of high importance when investigating impact locations, we compared three different approaches in regard of their reproducibility and precision. The results indicate that the piezoelectric acceleration sensor and the more sensitive capacitive sensor are well suited for further development and that the proposed setup provides a reliable basis for detailed analysis of the distinct signal characteristics. Additionally, the onset detection method based on calculating an energy signal and extracting the maximum amplitude of the impact appears to be the most precise method for the application described.

This study presents a comprehensive analysis of Speed Climbing athletes by examining motion parameters critical to elite performance. As such, several key values are extracted from about 900 competition recordings in order to generate a dataset for the identification of patterns in athletes’ technique and efficiency. A CNN-based framework is used to automate the detection of human keypoints and features, enabling a large-scale evaluation of climbing dynamics. The results revealed significant variations in performance for single sections of the wall, particularly in relation to start reaction times (with differences of up to 0.27 s) and increased split times the closer the athletes are to the end of the Speed Climbing wall (from 0.39 s to 0.45 s). In addition, a more detailed examination of the movement sequences was carried out by analyzing the velocity trajectories of hands and feet. The results showed that coordinated and harmonic movements, especially of the lower limbs, correlate strongly with the performance outcome. To ensure an individualized view of the data points, a comparison was made between multiple athletes, revealing insights into the influence of individual biomechanics on the efficiency of movements. The findings provide both trainers and athletes with interesting insights in relation to tailoring training methods by including split time benchmarks and limb coordination.

This study presents a comprehensive analysis of Speed Climbing athletes by examining motion parameters critical to elite performance. Thereby, several key values are extracted from about 900 competition recordings to generate a dataset for the identification of patterns in athletes’ technique and efficiency. A CNN-based framework is used to automate detection of human keypoints and feature, enabling large-scale evaluation of climbing dynamics. The results revealed significant variations of performance in single sections of the wall, particularly in start reaction times (up-to 0.27 s differences) and increased split times the closer the athletes get to the end of the Speed Climbing wall (from 0.39 s to 0.45 s). In addition, a more detailed examination of the movement sequences was carried out by analyzing the velocity trajectories of hands and feet. The results showed that coordinated and harmonic movements, especially of the lower limbs, correlate strongly with the performance outcome. To ensure an individualized view of the data points, a comparison was made between multiple athletes, revealing insights into the influence of individual biomechanics on the efficiency of movements. The findings provide trainers as well as athletes with interesting insights for tailoring training methods by including split time benchmarks and limb coordination.

Delocalized internal irradiation is a promising technique to intensify and scale up photochemical processes, as it prevents the otherwise unavoidable concentration of light energy. In particular, wireless light emitters (WLEs) powered by resonant inductive coupling showed promise in previous studies. However, the achieved photon flux was still relatively low. Herein, we show that through systematic optimization, the WLE technique can reach extremely high photon flux densities and energy efficiency, surpassing conventional photochemical reaction systems. Moreover, the intensification potential is demonstrated on the basis of a case study: the photocatalytic reduction of nitrobenzene in isopropanol using a TiO₂ photocatalyst. The results also reveal a significant advantage of the WLE system. Due to the decentralized light emitters, the local accumulation of photon energy is minimized, preventing efficiency losses due to kinetic limitations at high light intensity.

Article XXXVIII. Messtechnisches Symposium des AHMT in Hall in Tirol was published on April 16, 2025 in the journal tm - Technisches Messen (volume 0, issue 0).

Delocalized internal irradiation is a promising technique for intensification and scale-up of photochemical processes as it avoids the otherwise inevitable light concentration. In particular, wireless light emitters (WLEs) powered by resonant inductive coupling showed promise in previous studies. However, the achieved photon flux was still relatively. Herein, we show that through systematic optimization, the WLE technique can reach extremely high photon flux densities and energy efficiency, surpassing conventional photochemical reaction systems. Moreover, the intensification potential is demonstrated on the basis of a case study: the photocatalytic reduction of nitrobenzene in isopropanol using a TiO2 photocatalyst. The results also reveal a significant advantage of the WLE system. Due to the decentralized light emitters, light concentration is minimized which prevents or reduces efficiency losses due to kinetic limitations at high light intensity.

The calibration of 3D cameras is one of the key challenges to successfully measure the nightly 3D flight tracks of bats with thermal cameras. This is relevant around wind turbines to investigate the impact wind farms have on their species. Existing 3D-calibration methods solve the problem of unknown camera position and orientation by using a reference object of known coordinates. While these methods work well for small monitoring volumes, the size of the reference objects (e.g., checkerboard patterns) limits the distance between the two cameras and therefore leads to increased calibration errors when used in large outdoor environments. To address this limitation, we propose a calibration method for tracking flying animals with thermal cameras based on UAV GPS tracks. The tracks can be scaled to the required monitoring volume and accommodate large distances between cameras, which is essential for low-resolution thermal camera setups. We tested our method at two wind farms, conducting 19 manual calibration flights with a consumer UAV, distributing GPS points from 30 to 260 m from the camera system. Using two thermal cameras with a resolution of 640 × 480 pixels and an inter-axial distance of 15 m, we achieved median 3D errors between 0.9 and 3.8 m across different flights. Our method offers the advantage of directly providing GPS coordinates and requires only two UAV flights for cross-validation of the 3D errors.

Article Editorial. XXXVIII. Messtechnisches Symposium was published on September 1, 2024 in the journal tm - Technisches Messen (volume 91, issue s1).