Low oxygen availability in soil can impair root function, thereby decreasing agronomic productivity. Without oxygen to support mitochondrial respiration, energy levels in roots may limit mineral nutrient (N, P, K) transport. Traditional methods for measuring soil oxygenation include the use of redox electrodes and polarographic oxygen sensors. These approaches are limited to measuring oxygen co...

We report a new type of optical biosensor capable of differentiating between bulk and surface perturbations of the ambient refractive index as well as between specific and nonspecific binding of molecules on the sensor surface. The proposed detection scheme is based on tracking the shifts of hybridized bonding and antibonding optical modes in coupled optical microcavities (photonic molecules). ...

Crickets use a pair of hairy appendages on their abdomen called cerci, each of which contains numerous mechano-receptive filiform hairs (Fig. 1). These sensitive hairs can respond even to the slightest air movements, down to 0.03 mm/s, generated by the approaching predators and initiating an escape mechanism in the crickets [1]. Bio-mimicking the cricket cerci, arrays of artificial hair sensors...

I. OVERVIEW Field estimation is an important application of wireless sensor networks. This type of application deploys sensor nodes in a specific region to remotely sense space-temporally variable processes. The spatial and temporal frequencies of sampling directly impact the quality of the estimation. Therefore, there is a tradeoff between the frequency and the number of samples transmitted, w...

A bio-inspired absolute pressure sensor network has been developed. Absolute pressure sensors, distributed on multiple silicon islands, are connected as a network by stretchable polyimide wires. This sensor network, made on a 4'' wafer, has 77 nodes and can be mounted on various curved surfaces to cover an area up to 0.64 m × 0.64 m, which is 100 times larger than its original size. Due to Micr...