In order to save time and avoid overheating of food during unfreezing, the study of ice content can be very useful. The aim of the research is to design an ultrasound-based sensor system that is able to comment on the content of ice in the sample food product. Some sample food products are tested, and the observations and challenges concerning the same are mentioned in the research paper.

Mathematical models are often required to process sensor data in a digital twin platform. The translation of models to an updateable format enables predicting hidden states of the physical object, which are not directly measurable. The linking of different models is demonstrated by data from field tests on fruit transportation in refrigerated containers. We programmed a streaming platform that enables easy integration of such updatable models with only a few milliseconds of processing overhead.

The development of optical design is characterized by the desire for more applications and better performance. The latest result of this development is freeform optics offering almost unlimited possibilities for the designers. However, an optical component has also to be manufactured and tested by metrology. We propose a measurement technique for the surface characterization of freeform optical components and highlight the possible error sources and their influence on the measurement result.

We combine two modern trends in component fabrication, namely, the integration of sensors into machine parts and the 3-D-printing technology, which is rapidly emerging in the fabrication of standardized and customized components and prototypes. We present a 3-D-printed ‘smart’ screw with an integrated strain gauge. The signal of the sensor can be used to monitor the fastening process of the screw as well as the reduction in strength of the screw joint over time.

A new packaging method to mount a membrane-based thermal flow sensor, flush with the surface, is presented. Therefore, a specific design for the housing is shown that is also adaptable to other conditions. It has been experimentally shown that it is important to mount the sensor flush with the surface. If not, vortices can occur (depending on velocity and the fluid properties) or the reduction of the channel cross section plus a decrease in sensitivity have to be taken into account.