| With constant human intervention posing a growing threat for natural ecosystem, there is a current need to develop a sensor system for continuous environmental monitoring to help humans restore ecological balance. Applications of such systems can be waste water control, air pollution control, human health monitoring, to mention a few.;In this work, we present a prototype, modular, autonomous multifunctional sensor system that will be useful for long-term in-situ applications. Multifunctionality stems from various sensing mechanisms to determine the concentration of pollutants. The sensor system is a combination of a custom CMOS-based integrated circuit (IC) that contains a photodiode and charge sense amplifier, a microcontroller for autonomous operation and a fluid handler. The detector can respond to color change in a liquid under test as well as intensity change from a luminescent chemical sensor. Autonomous and 'plug-and-play' nature of our system will make it suitable for various in-the-field uses; e.g. real time monitoring of potential source run-off sites of the pollutants responsible for water pollution. Test results indicate this as a successful design, but at the same time, provides ample encouragement to develop a robust, low-cost and low-power environmental sensor system. |
