Electronic Sensor Nodes Powered over Fibre Optimized for Ultra-Precise Temperature Measurements in Magneticresonance Imaging Machines

Summary: Sensorial materials are fundamental for new intelligent products. Implementing sensorial functions and local data processing capabilities into the materials will lead to intelligent products that can “feel” and “judge” and therefore interact with other systems, human users and the environment, contributing to our efforts towards energy savings, safety and security, mobility, and health. To realize this vision, the DFKI, with other national industrial and scientific, is developing intelligent sensor nodes connected by optical fibres in a largescale sensor network. In contrast to other wired or wireless sensor networks, both a high-speed data link and power supply are realized via an optical fibre. This makes batteries or other local energy sources for the sensor nodes superfluous and the network immune against strong electro-magnetic influences, which are typical for harsh industrial environments or some medical applications like magnetic resonance imaging. In addition, the lack of a local energy source reduces significantly the sensor node’s size and makes it completely maintenance-free which is a key aspect for the integration into new materials. The paper briefly describes the general idea of ultra-low power electronic sensor nodes and the joint transmission of data and power over optical fibres as well as its realization. As an example, a first industrial application is presented, making use of the system’s electro-magnetic immunity for highly precise multichannel temperature and acceleration measurements in magnetic resonance imaging machines. In addition, the key factors for achieving a greater flexibility compared to classical fibre optic sensor networks are pointed out.