SBIR-STTR Award

Monitors that are currently used to periodically record bottom water temperatures cannot be read by the lobstermen who use them. In addition, current monitors make no provision for recording changes in depth if they are redeployed in a different location. The specific aim of this proposal is to develop a sensor that will measure water temperature and pressure hourly and will be readable by a radio frequency (RF) signal from a standard hand-held computer. Data will be immediately available for graphical display by the user. The sensor will be designed for minimal power consumption, to provide extended batter life, and will be recharged by RF induction, allowing the unit to be completely and permanently sealed.

Potential Commercial Applications:
Temperature/pressure sensor with real-time readout for use in the lobster industry and in other areas of the fishing industry. Diverse uses generally in environmental monitoring of aquatic conditions in oceans, lakes, reservoirs, rivers and streams. Other potential commercial uses include temperature/pressure monitor for liquids during manufacturing (e.g., during fermentation) and as a swimming pool temperature monitor

In Phase I a sensor package was developed that takes hourly measurements of temperature and pressure for use in the eMOLT program. Since these data are collected by working lobstermen, ease-of-use is critically important for maintaining their participation. The sensor package monitors pressure to determine whether the lobster trap to which it is attached has been hauled on deck. When this occurs data is automatically transferred via Bluetooth communication protocol to a palm-top computer. Current or historical data can be displayed on the palm-top at any time. In Phase II, a salinity sensor, based on a new class of MEMS devices developed by ADC, will be added to the package. These sensors use the swelling response of hydrogels to pH to change their capacitance. Since this is not a conductivity measurement it should be highly immune to fouling. Research will focus on sensor optimization and functionalizing new hydrogels to respond to salinity. In addition, the system will be further automated to use a satellite uplink to transfer data to NOAA. Position will be determined using GPS and automatically transmitted with environmental data.

Potential Commercial Applications:
Given recent findings of source waters entering the New England fishery from the North there is an obvious need to assess the influx of the fresher (low salinity) water mass as it is transported into and around the Gulf of Maine. Is there a detectable increase in the Canadian ice melt waters? Will climate change have a significant effect on the conditions of our coastal waters? For purposes of monitoring the influences of advective water masses, salinity is an effective tracer. The addition of a salinity sensor to the package developed in Phase I will make it a more useful tool for long term studies such as eMOLT. Incorporating a hydrogelMEMS sensor will make possible the monitoring of many other seawater parameters. Hydrogels can be tailored to respond to specific chemical compounds. Toxins from algae blooms or concentration of pollutants such as nitrates from the influx of fresh water could be sensed. The salinity sensor will be an ideal feasibility demonstration