This article describes a new qualification concept for dimensional measurements on optical measuring systems, using the example of a prototypical multi-scale multi-sensor fringe projection system for production-related inspections of sheet-bulk metal-formed parts. A new concept is developed for determining the orientations and positions of the sensors' measuring ranges in a common coordinate system. The principle element of the concept is a newly developed flexible reference artefact.

Infrared cameras based on microbolometer focal plane arrays (FPAs) are the most widely used cameras in thermography. For acceptable measurement uncertainty values, the disturbing influences of changing ambient temperature have to be considered. We propose a TEC-less and shutter-less correction approach based on additional temperature measurements inside the IR camera. The effects on the pixel responsivity and offset voltage are considered separately.

The aim of this paper is to discuss different models that describe atmospheric transmission in the infrared. They were compared in order to choose the most appropriate one for certain atmospheric conditions. Universal models and different inaccuracies connected with them were analysed in this paper. There have been models analysed from the literature, and these are used in infrared cameras.

A manufacturing process for a planar binary lambda sensor is shown. By joining the heating and the sensing components via glass soldering with a joining temperature of 850 °C, a laboratory platform has been established that allows the manufacturing of two independent parts in HTCC technology with electrodes that are post-processed at lower temperatures, as is required for mixed-potential sensors. The concept has been proved by comparing the device with a commercial sensor.

Tracer gas experiments demonstrate possible pathways of toxic gas propagation, especially in subsurface infrastructures like subway stations. Precise gas sensors are needed to record the concentration levels over time; thereby, a better understanding of how smoke or toxic gas affected evacuation routes can be achieved. The acquired knowledge can be used to optimize evacuation and reaction plans and might reduce the casualties in catastrophic circumstances.

Hydrogels are swellable polymers, which exhibit superior sensor properties. However, the exploitation of these properties for innovative measurement technology has been prevented by the lack of a manufacturing technique for thin hydogel films that suits industrial needs. We suggest a paradigm change from the current recipe-driven sensor manufacturing to a specification-driven one. Our contributions are optimized processes for a controllable film formation and thermal curing of the hydrogels.

The article reports about the development of novel microfluidic sensors that are directly attachable on 3-D polymers. An ability to integrate electrical and fluidic parts into the 3-D platform brings the sensors to a new level of miniaturization. The sensor system is made of a flexible polymer featuring a system of metal electrodes and a rigid polymer carrier with all external macroconnections. To the concentration of ethanol in DI water the sensor system showed the desired sensitivity.

Many different techniques have been introduced in an effort to maximize heterogeneous wireless sensor lifespan, but these techniques have focused on having the nodes in a cluster send their data to a selected cluster head node that, in turn, reports the data to the base station. Therefore, the choice of the number of clusters and the way the cluster head node is selected are the main focuses of this research paper.

In this work, a ceramic housing was designed using the versatile low-temperature cofired ceramics (LTCC) to test this technology at temperatures above 400°C. Inside the housing, a prototype sensor chip was mounted to monitor the signal quality during an applied heat treatment up to 600 °C. All devices failed at around 450–500 °C due to material migration from the glass seal of the housing to the sensing structures of the mounted chip. Elemental analysis identified bismuth as a contaminant.

This work presents a novel design of a low power high-temperature MEMS elliptical capacitive pressure sensor that can be utilized within wireless sensor systems, e.g. TPMS. Throughout numerical and analytical analysis, it was found that sensor sensitivity and temperature resistance could be increased if the diaphragm area has two symmetrical segments of chords parallel to the major axis removed, and if diaphragm deformation increases the separation distance between the sensing capacitor plates.

This paper investigates the effect of high-temperature and low-temperature (< 150 °C) processing conditions on the surface composition of the substrate. Furthermore, the resultant transducers from high- and low-temperature fabrication processes are compared to determine if a low-temperature processing method is feasible. For these studies a sol-gel spray-on process is employed to deposit piezoelectric ceramics onto a stainless-steel 316L substrate.

The interaction of sound and flow enables an efficient noise damping. Understanding this aeroacoustic damping phenomenon requires simultaneous measurement of flow and sound fields. Using a high-speed CMOS camera, two-component flow velocity measurements are performed in a three-dimensional region of interest. The sensor system can simultaneously capture sound and turbulent flow velocity oscillations. The presented measurements reveal that the sound energy is transferred into flow energy.

Magnetic resonance imaging (MRI) is a powerful tool for biological investigations. Nevertheless, the imaging resolution performance results in the combination of the static magnetic field strength and the radio-frequency coil efficiency. In the context of spinal cord lesion studies, a ribbon solenoid coil is used to enhance the imaging quality of the MRI experiment on a tissue allowing one to perform high-resolution imaging with potential benefits for biological studies.

For the application of indoor air quality monitoring, two types of tungsten oxide gas sensor layers were prepared via pulsed laser deposition. Analysis of the structure of the produced layers showed that they consist of nanoparticles and agglomerates of nanoparticles. The sensors showed significant sensitivity and selectivity towards naphthalene in the ppb concentration range. The results were achieved using temperature cycled operation of the sensors and pattern recognition signal treatment.

The continuous monitoring of industrial and environmental processes is becoming an increasingly important aspect with both economic and societal impact. To realize this task, spectral-optical sensors with their outstanding properties in terms of sensitivity and reliability are a potential solution. However, for exploiting these sensors in a cost- and energy-efficient sensing system, a miniaturized readout unit is needed. Here we present a card-size, inexpensive, and robust readout electronics.

Piezoelectric devices are characterized non-destructively to ensure their functionality. The material is heated by laser diodes. The resulting temperature changes lead to a pyroelectric current. Analytical and numerical finite element models describe the temperature distribution and the current in frequency and time domain. Modelling and experimental results are compared for piezoelectric plates and integrated sensors and actuators.

Metamaterials are artificial composite structures with unusual physical properties such as the perfect absorption of light, which can be exploited to improve the spectral sensitivity and selectivity of thermal detectors. The desired detector characteristics are engineered by tuning the absorption properties of metamaterials. The numerical simulations demonstrate polarization-independent absorption of disc-shaped dielectric/metallic absorbers and their integration capability in thermal detectors.

Indium oxide inverse opal is a promising new material for optical gas sensors. The photonic properties caused by the inverse opal structure can be utilized to read out the sensors’ electronical state by optical methods. The maintenance of good thermal stability of transducer material during operation is a minimum requirement. We present results on the synthesis and investigation of the structural stability of the In₂O₃ inverse opal structure up to a temperature of 550 °C (limit of substrate).

We present a non-destructive method to determine the material properties, for example elastic constants, of metal and polymer plates using laser-generated ultrasound. The ultrasonic signals are detected using an ultrasonic transducer that shows high sensitivity over a wide rage of frequencies. A method of signal processing to determine material properties is described and can be expanded upon to characterize more complex samples, such as fibre reinforced composites.

The exploitation of new application fields and the drive to size reduction even in highly stable pressure sensing systems makes the extension of the operating temperature range of the microelectromechanical sensors (MEMS) essential. For this reason, a silicon-based pressure sensor with an application temperature ranging up to 300 °C and the associated manufacturing technology was developed. The evolved sensor has an excellent stability and is uncomplicated to mount due to its stress insensitivity.

Initial steps to apply a new ceramic multi-layer sensor for a Tian–Calvet calorimeter are shown. The FEM-developed sensor consists of stacked ceramic discs and insulation rings. The functionality of the sensor disc was proven up to 600 °C and the entire stack was tested at room temperature. The resolution was 5 µW and the sensitivity was 8.5 µV mW⁻¹. The new sensor shows similar specifications as commercial devices and presents a good starting point for future high temperature applications.

Sensor particles with buoyancy control and position detection are presented, which are used for flow tracking in large vessels, such as biogas digesters and waste water tanks. They were tested in the realistic flows of a biogas digester. The buoyancy control allows taring for good flow tracing by the sensor particles, and it lets them float to the surface after data acquisition for easy recovery. The fluid mixing was estimated from detected passages of sensor particles at a magnetic coil.

A novel cell-cultivation platform with small circulating volume and included oxygen controlling system is presented. This system may be used to investigate the influence of oxygen restriction, called hypoxia, to cultivated human cells and therefore helps to reduce animal testing in this field of research. Furthermore, a mathematic model of the oxygen transport is presented which may be utilized to produce well-defined oxygen microenvironments.