The advent of smart materials, structures and systems on the one hand and the fear of burgeoning terrorism across the globe on the other hand have led to an extensive demand of sensors and actuators having tailor-made properties. Amongst different sensors, gas and vapour sensors are increasingly needed for safety, environmental monitoring and process control and find applications in diverse areas, e.g. monitoring of toxic gases like carbon monoxide, sulfur dioxide, chlorine, combustible gases like methane, LPG, CNG, hydrogen, automobile exhaust pollutants like SOx, NOx, hydrocarbons and measuring and controlling humidity for industrial, nuclear and domestic sectors. Also gas sensors in the form of array or e-nose are of paramount importance for detection of explosives, nerve gas, freshness of fruits and fish, monitoring tea aroma and in medical diagnostics like breath alcohol analyzer, diabetes detection etc. Presently our activity includes development of solid state sensors for detection of methane, LPG, CNG, carbon monoxide, sulfur dioxide, trace moisture, alcohol (breathalyzer) and acetone(biomarker of diabetes in breath).
Basically, a smart structure consists of sensors, actuators and control circuit. An actuator is a transducer capable of transducing an input energy into mechanical energy (displacement/force). Piezoelectric materials are currently used in a variety of applications as sensors and actuators and they play a pivotal role in the arena of smart materials and structures. Ultrasonic structural health monitoring (SHM) is an area where piezoelectric materials in the form of wafers/patches can act as both actuators and sensors. Our present activities include development of multilayer piezoelectric actuators, piezoelectric wafers, and lead-free piezoelectric materials. We have also initiated work on energy harvesting devices using piezoelectric materials.
Recently, to boost collaboration so as to get a tangible outcome, "Sensor Hub" has been formed at CGCRI under the patronage of DST and CSIR. Presently, in the Hub, along with CGCRI, other Institutes in and around kolkata, who have been involved in sensor and related activities for a long time, viz., Jadavpur University, Calcutta University, Bengal Engg. & Science University and Centre for Development of Advanced Computing (C-DAC), Kolkata have joined hands to develop, fabricate and test electronic nose for tea aroma, MEMS-based battery operated methane and carbon monoxide sensors and arsenic detection kits. The Hub will provide pilot production and testing facilities of sensor and sensor array modules for food, agriculture and environmental applications so that the developed technologies can be transferred directly to the interested parties.