Development of lightweight, power-efficient, soft electronic sensor systems for next-generation oceanographic measurements

PI: Wang, Xueju (University of Connecticut)
Co-PI(s): Deng, Zhiqun (PNNL) : Rogers, John (NU) : Morozov, Andrey (Teledyne)
Start Year: 2021 | Duration: 2 years
Partners: University of Connecticut, PNNL, NU, Teledyne

Project Abstract:

Research Problem and Objectives
Conventional electronic ocean sensors for monitoring and recording various environmental parameters require high-pressure chambers and seals, which usually entail large powersupply and size ofthe sensorsystem. The emerging softmatter electronics, which are thin, flexible electronic sensors embedded in soft incompressible elastomers, are a promising candidate for underwater sensing because they can withstand large hydrostatic pressure and potentially eliminate the needs for high-pressure chambers. The major challenges in developing soft electronic ocean sensors are: 1) to extend their current data communications, which are usually Bluetooth or near field communication, to underwater applications and maintain a reasonable range and rate, 2) to develop a fully integrated sensor system that can survive the harsh ocean environment, and 3) to increase technology readiness levels (TRL) in system integration and data transmission. To address these challenges, the proposed work will develop a power-efficient, small size, autonomous soft sensor system that can interface well with underwater acoustic communication for nextgeneration in-situ oceanographic measurements, and increase its TRL from 3 to 5 through extensive lab and field testing.

Technical Approach
In this project, we will choose conductivity, resistive temperature and pressure (CTD) sensors as a model sensor system, which will be fabricated by patterning ultrathin metal films and encapsulated with robust soft polymers to perform measurements in harsh ocean environments. An underwater acoustic communication system will be integrated with the soft ocean sensors for underwater data transmission. We will design and fabricate a multilayer flexible printed circuit board (PCB) and integrate all electronic components including soft sensors, microtransducers, and microcontrollers into a soft and flexible sensor system. The integrated sensor system will be calibrated and tested in lab (customized pressure tanks) and ocean environments. We will also perform comparative studies between our developed soft sensor system and conventional ones, and evaluate their performance in terms of measurement range, accuracy, and power consumption.

Anticipated Outcome & Impact
If successful, the proposed work will develop a flexible, soft electronic ocean sensor system that can substantially reduce the power requirement, size, weight, and cost of autonomous ocean sensors for next-generation oceanographic measurements. The direct outcome of this project is a prototype of a soft CTD sensor system that has thin geometry, high flexibility and stretchability and excellent interface with underwater acoustic communication for ocean sensing. It can be integrated with many platforms including animal tags, profilers, and diver equipment. Through iterative lab and field testing, we expect to improve the TRL of soft CTD sensors from 3 to 5. The development of the soft ocean sensor system represents a critical step in the overall technology map of Navy’s growing push for reducing the power requirements and size of in-situ ocean sensors. This breakthrough will create new avenues for next-generation oceanographic measurements and greatly enhance Naval capabilities in underwater sensing.