We present a 3D gas schlieren imaging sensor (3D-GSIS) for reconstructing vehicle exhaust plume density fields. It estimates plume size, laser absorption path lengths, intersection points of lasers, and local densities. Combined with advanced remote emission sensing, it enables direct measurement of pollutant concentrations in exhaust plumes.

A non-contact, optical methodology suitable for high temperatures based on laser-Doppler vibrometry is presented to directly determine piezoelectric constants. LiTaO₃ is chosen as a model material as it is a representative piezoelectric material with applications in sensors and surface acoustic wave devices. The values determined range from 12 pm V^-1 at 21 °C to about 15 pm V^-1 at 400 °C, being in good agreement with the literature. Thus, the proof of concept for this approach has been obtained.

We present an eight-channel evaluation board for ultrasound sonography and photoacoustic imaging. High frame rates enable averaging, improving signal-to-noise ratio. The board integrates a programmable preamplifier and an analog front-end with 12-bit analog-to-digital conversion, with data transmitted via Ethernet for PC evaluation. Gain distribution and its effect on signal-to-noise ratio in a multichannel photoacoustic receive chain are quantitatively characterized at 540 frames per second.

Automation in measurement tracking improves quality management by reducing human interaction and manual data risks. To enable this, all metrological and administrative data in quality certificates must be machine-readable. Digital calibration certificates (DCCs) meet this need and enable fully automated compliance checks. A temperature-monitoring demonstrator illustrates their automation potential. Its code is published for reuse.

We developed a simple and versatile sensor that can detect harmful substances more effectively. By improving how the sensor's key component, the membrane, is made, we matched it better with the materials used to capture target chemicals. This makes the sensor easier to build and more reliable. Our work shows how choosing the right membrane material can greatly improve performance, opening the way for broader applications in detecting pollutants.

Scanning electron microscopy (SEM) and atomic force microscopy (AFM) enable sub-nanometer surface imaging and complement each other's limitations. Integrating AFM into a SEM vacuum chamber combines their strengths. However, vacuum increases the cantilever's Q factor and reduces scan speed. We develop a feedback circuit and a piezoelectric MEMS cantilever to tune the Q factor, enabling vacuum AFM at air-like speeds.