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We pursue a promising novel self-adaptive spiking neural analog-to-digital data conversion (SN-ADC) design that uses spike time to carry information. Thus, SN-ADC can be effectively translated to aggressive new technologies to implement reliable advanced sensory electronic systems. The SN-ADC supports self-x (self-calibration, self-optimization, and self-healing) and machine learning required for the internet of things and Industry 4.0 and is based on a self-adaptive CMOS memristor.

The method of non-contact temperature measurement in conjunction with a 3D sensor described in this paper can be used to determine the heat loss of technical devices and industrial plants. This measurement tool thus helps to optimize the energy efficiency of these devices and plants.

An adjustment concept for high-precision weighing cells has been developed and experimentally investigated. It allows for minimization of uncertainty contributions due to tilt while maximizing sensitivity to mass. By applying the adjustment capabilities to new weighing cells, the devices can simultaneously become more accurate, more adaptable and more robust.

The Physikalisch-Technische Bundesanstalt calibrated pyroelectric detectors at two independent primary radiometric standards regarding their spectral responsivity. The SI traceable measurements in the spectral range between 1.5 and 14 µm are consistent within the measurement uncertainty in the range of 1 % and 14 %. The importance of the correct read-out of lock-in amplifiers and the accurate consideration of the temporal shape of the chopped radiant flux behind the chopper wheel are shown.

This work shows a possibility of assembly and connection technology for use under high temperatures up to 1000 °C. A packaging concept was developed, and all the necessary material and joining technologies have been verified to be suitable for use at 1000 °C. A working sensor was built and measured in comparison to the resonator alone. All packaging materials and structures were measured electrically and dielectrically. Equivalent circuits for the packages up to 2 MHz and 1000 °C are available.

Digitalization is gaining momentum. Therefore sensory functions have to be integrated into rotating systems and harsh environments, requiring a reliable energy supply. To support product designers an estimation model for an autonomous sensor node is derived from basic electrical relations and simplified to make it usable for designers. Subsequently the model is used to define operation strategies influencing the energy consumption, which are tested in different ambient conditions.

The paper proposes a structure for the creation of new simulation software for uncertainty estimation. The structure was derived from the well-established VCMM. To make it easy to apply the software structure to specific projects, a supporting software library (written in C++) was created. The library provides all the components necessary to create software for uncertainty estimation. The software structure and library proposed can be used in different domains of metrology.

A newly developed experimental setup to characterize thin polymeric films during dehydration and hydration is presented. The great advantage of this measurement device and technique is that it monitors the mass change and conductivity of the films in situ and simultaneously at virtually identical conditions. The feasibility of the technique is demonstrated by characterizing ionomer thin films. A mass resolution of ±7.9 ng is achieved. The precision of relative humidity (RH) control is ±0.15 %.

We develop sensor material to effectively transform mechanical force or torque into an electrical resistance. A new type of thin films containing nickel and carbon has a significantly higher output and is thus very advantageous. But so far, the electrical resistance lacks stability. We therefore investigate how to stabilize the material and show that the partial replacement of nickel by the element chromium solves the problem. The optimized sensor films are now suitable for widespread use.

Tracking individual parts in manufacturing processes helps to lower production cost by assigning a full record of production steps to each part, and therefore enabling targeted quality control. A novel approach is presented, which shows that the printing quality can be monitored using images of the printed result only. Analysing data from long-term tests shows which characteristics of the part marking are suitable to be used as indicators for maintenance needs.

We motivate how integrated waveguides (WGs) can be part of an on-chip non-dispersive infrared sensor system for environmental sensing. We report the hurdles in maintaining WG quality when integrating emitter and detector structures on the same chip. Thus, we introduce the concept of how to determine the intrinsic loss and a process scheme to protect WG structures from damage caused during fabrication. This could pave the way to systems for environmental sensing with a minimal footprint.

We describe the development and characterization of a three-dimensional (3D) magnetic coil system that is able to produce magnetic flux densities of up to 2 mT in an arbitrary field direction. The coil system can be used to calibrate 3D magnetometers efficiently, and the measurements are traceable to national SI units.

This work deals with process monitoring. In particular, the process of used-sand regeneration is monitored with the aid of impedance spectroscopy and can be controlled in the future with the measurement data obtained in this way. This results in the following aspects: a consistently high quality of the process material is realized by a controlled process. At the same time, energy consumption is minimized. The result is a process that is both more resource-efficient and more economical.

High-temperature stable piezoelectric resonators are coated with oxide electrodes. The impact of the oxide electrode conductivity on the mass sensitivity and on the resonance frequency of the device is described by electrical and mechanical models, which are used to analyse the experimental data. Furthermore, the impact of an increasing oxide electrode conductivity is discussed with respect to the application of oxide electrodes and for gas sensing.

The present research work investigated the acoustic manipulation of bioparticles and cells in closed and liquid-filled vessels using a special method for focusing acoustic fields. Based on simulation studies, the feasibility of particle manipulation with this method was successfully demonstrated. Successful final testing using a demonstrator and thus the transfer and prospective application in biotechnology are part of further research work.

Gas analysis by absorption spectroscopy helps to optimize combustion processes in engines. Optical distance sensors are non-contact and offer high accuracy and precision. Both sensor applications benefit from light sources with a rapidly swept wavelength to monitor dynamic processes. In our paper, we precisely characterize the dynamic wavelength sweep of a rapidly pulsed VCSEL (vertical cavity surface emitting laser), a tiny semiconductor laser well suited for optical sensing.

In this paper, a near-infrared LED system is proposed for autonomous vehicles to distinguish between weather-induced road surface conditions (dry, wet, snow, ice, water). For the LED spectra, the influence of the LED bandwidth is investigated. To assess the performance of the system for a long detection range, experiments with large incident angles are conducted. The feasibility of this system is proved via a laboratory experiment with three near-infrared LEDs and a camera.

Modern production concepts generate a demand for reliable, energy-efficient, fast, and secure wireless communication solutions. Therefore, the current consumption should not increase substantially due to additional security operations. This paper shows a principle current measurement method that is exemplary of a transceiver for IO-Link Wireless protocol. The results show that the current consumption only increases slightly with acceptable measurement uncertainty.

In this contribution the frequency domain fluorescence lifetime imaging microscopy (FD-FLIM) technique is evaluated for post-consumer wood sorting. The measured data were processed using algorithmic decision trees to identify the wood species and post-consumer wood category. The experimental results revealed the high potential of the FD-FLIM technique for automated post-consumer wood sorting.

It is a great challenge to apply a diagnostic system to engine test beds. The main problem is that such test beds involve frequent configuration changes. Therefore, the diagnostic system must be highly adaptable. A modular toolbox-based approach combines physics-based and data-driven modeling concepts and, thus, enables highly flexible application. Adaptability and detection quality are validated using measurement data from a single-cylinder engine and a multicylinder engine.

Acceptance and reverification testing for industrial CT systems is described in different standards. The characterisation and testing of CT system performance are often achieved with test artefacts containing spheres. This simulative study characterises the influence of different geometrical error sources – or geometrical misalignments – on these sphere measurements.

The measurement principle shows how to measure calibration torque moment shunts in a 5 MN m torque standard machine using an interferometer and hinge flexure stiffness. The analysis of the measurement uncertainty influences shows that the measurement uncertainty of transversal force measurement ranges from 0.61 % to 3.04 % and stays constant at 1.7 % for torque measurement. A FE validation was performed. The measurement uncertainty of the calibration torque moment sank from 0.106 % to 0.100 %.

Industrial X-ray computed tomography is a holistic measurement technique for dimensional metrology. However, the relatively long measurement time is a hindrance to its application. A possibility to reduce measurement times, the continuous scan mode, is characterized in this work. The question is how much the time reduction impacts the accuracy of the dimensional measurements. The core result of the paper is an estimate of the effect along with experimental proof that this estimate is reasonable.

The paper presents a specimen and evaluation method for interface structural resolution testing of X-ray computed tomography systems based on CT simulations. The geometry is oriented to the norms of image quality investigation. The evaluation is based on profile lines of the cross-sectional images that pass through the boreholes. All statements on resolution refer to the entire measurement chain and, thus, in addition to the reconstruction algorithm also to the surface determination method used.

We present a photoacoustic sensor enabling fast, inexpensive, and highly sensitive methane detection in environmental monitoring applications. Six different T-cell designs were both theoretically and experimentally investigated. The aim was to understand the photoacoustic signal generation and resonances in relation to the different cell geometries, and determine the long-term stability and the detection limits for methane. These were below the methane background concentration in air of 1.8 ppm.

A fundamental problem of machine learning (ML) is measurement uncertainty and the influence on ML results. Measurement uncertainty, which is critical in hazardous gas detection, is directly addressed in this paper. A previously published toolbox is extended for regression. One of the benefits of this approach is obtaining a better understanding of where the overall system should be improved. This can be achieved by either improving the trained ML model or using a sensor with higher precision.

Differential scanning calorimetry (DSC) is a widely used tool to analyze thermal material properties. This study focuses on the advancement of a miniaturized DSC chip as an alternative to conventional devices. The first development steps for the integration of a weighing system are shown, starting with model considerations and simulation-based optimization to initial measurements. Three different measurement methods are investigated and show promising results.

Diabetes Mellitus (DM) is one of the very common diseases with no viable cure. However, it can be controlled by regulating the daily sugar intake. Diabetic patients need to prick their fingers a few times a day for monitoring sugar levels. To find an alternative, researchers have been working for decades on the development of a true non-invasive technique. In this effort, we developed a cost-effective non-invasive technique for measuring blood sugar levels using capacitance spectroscopy.