Broadband dielectric spectroscopy measurements of biological materials within RF/microwave range can reveal cellular information, which is of important value in biological and medical researches. Here, we present a platform that combines a miniaturized coplanar waveguide (CPW) transmission line (TL) sensor and a special CPW-fed interdigitated capacitor (IDC), which allows us to measure the complex permittivity of cell cultures from 300 kHz to 50 GHz. The CPW-TL and CPW-IDC sensors are integrated with an SU-8 microfluidic channel, enabling measurements of microliter or even nanoliter volumes of liquids and suspensions. Due to the accurate alignment of the SU-8 polymer and the reliable liftoff fabrication procedure, we are able to minimize the measurement errors caused by the sensors' dimension tolerance. To ensure accurate complex permittivity extraction of the tested material, related calibrations and deembedding processes are explained. With the measurement of deionized water as a validation, the platform is used to measure the complex permittivity of both a yeast cell culture and a mammalian cell culture. We elaborate on the interesting findings and discuss future possibilities.

Sensors are integrated into collaborative robot systems to ensure the safety of human workers by allowing them to perceive their environments, detect human presence, and adjust their actions accordingly. This PRISMA scoping review focuses on current sensor-enabled safety systems for human-robot collaboration in the manufacturing industry based on both scientific papers and patents. From the initial search of 6669 references, 281 underwent full-text review and segmentation based on sensor technology, installation location, and safety operating mode according to the ISO/TS 15066 standard. In the last decade, there has been a clear trend of increasing sensor-enabled safety systems. The dominant sensors used are infrared-structured light, capacitive, LiDAR, resistive, stereo/depth camera, RaDAR, and laser scanners. The primary safety operating mode identified was Speed and Separation Monitoring (SSM). Some systems integrate multiple sensor types, with the most common combinations being LiDAR with stereo cameras or LiDAR with capacitive sensors, and laser scanners with RaDAR. We suggest multi-sensor integration and standardized benchmarks for future development. This review is among the few that employ the PRISMA protocol to study sensor technologies and contribute to a more systematic understanding of the current state of the art in this area.

Due to its noninvasive property, the interdigital capacitor (IDC) has been applied in dielectric liquid detection and characterization. In order to integrate the IDC sensor on a lab-on-chip, it is often required to minimize and optimize the sensor for sensitive and efficient performance. However, the conventional numerical simulation approach is quite time-consuming. Therefore, an efficient analytical method is proposed herein, leading to accurate capacitance and conductance expressions of an arbitrary multilayer-structured IDC. The model is validated with practical measurements of a series of coplanar waveguide (CPW) structure-based IDCs. In addition, an accurate characterization function, which relates the IDC capacitance and conductance to the complex permittivity of a material loaded on the top of the IDC sensing area, is obtained. The characterization function shows good agreement with the finite-element method (FEM) simulation results, which demonstrates the capability of the IDC sensor in dielectric spectroscopy measurements of μL and even nL liquids.

A wideband microstrip comb-line antenna array is developed for 79 GHz MIMO radar applications. This array is composed of 4 radiating sub-arrays, with 180 degrees phase shift. This topology leads to a more stable radiation pattern behavior and broadside gain flatness along the frequency bandwidth. The antenna is taped out with a new high resolution multi-layer PCB technology, called "Any-Layer PCB". This technology provides the possibility to stack small micro-vias, instead of using thick machine drilled vias. A measured impedance and gain bandwidth of 12.5% is achieved. The side lobe suppression is higher than 15 dB, and the array gain is 12.36 dBi at 79 GHz.

This work proposes a first-of-its-kind SLAM architecture fusing an event-based camera and a Frequency Modulated Continuous Wave (FMCW) radar for drone navigation. Each sensor is processed by a bio-inspired Spiking Neural Network (SNN) with continual Spike-Timing-Dependent Plasticity (STDP) learning, as observed in the brain. In contrast to most learning-based SLAM systems, our method does not require any offline training phase, but rather the SNN continuously learns features from the input data on the fly via STDP. At the same time, the SNN outputs are used as feature descriptors for loop closure detection and map correction. We conduct numerous experiments to benchmark our system against state-of-the-art RGB methods and we demonstrate the robustness of our DVS-Radar SLAM approach under strong lighting variations.

Open-ended coaxial probes are widely used to gather dielectric properties of biological tissues. Due to the lack of an agreed data acquisition protocol, several environmental conditions can cause inaccuracies when comparing dielectric data. In this work, the effect of a different measurement probe-to-tissue contact pressure was monitored in the frequency range from 0.5 to 20 GHz. Therefore, we constructed a controlled lifting platform with an integrated pressure sensor to exert a constant pressure on the tissue sample during the dielectric measurement. In the pressure range from 7.74 kPa to 77.4 kPa, we observed a linear correlation of $-0.31\pm 0.09$ % and $-0.32\pm 0.14$ % per kPa for, respectively, the relative real and imaginary complex permittivity. These values are statistically significant compared with the reported measurement uncertainty. Following the literature in different biology-related disciplines regarding pressure-induced variability in measurements, we hypothesize that these changes originate from squeezing out the interstitial and extracellular fluid. This process locally increases the concentration of membranes, cellular organelles, and proteins in the sensed volume. Finally, we suggest moving towards a standardized probe-to-tissue contact pressure, since the literature has already demonstrated that reprobing at the same pressure can produce repeatable data within a 1% uncertainty interval.