The sensor system can save a life from landslides at a mere Rs. 700
Mandi, Himachal Pradesh (ISJ): A research by University of Sheffield, London revealed, India accounted for 20 percent of fatal landslides across the world during the period 2004-2016, causing over 10,000 deaths.
"The most tragic event identified by the researchers was the Kedarnath landslide in June 2013 in India, which resulted in over 5,000 deaths," said the researchers. "It was due to extreme weather conditions that caused flash floods and massive mudflows, which affected thousands of religious pilgrims trapped in the mountain area."
The latest disaster in Kerala in August 2019, killed 121 people in floods and landslides in the state's Waynad district in the absence of any system to warn them of the impending disaster.
Indian technologists have now developed a sensor that could alert landslides, thus saving precious lives.
The sensor technology made of a micro-electromechanical system contains a small machine consisting of mechanical and electronic components at the micrometre level.
"The accelerometer, which is one of the sensors, senses two kinds of motion (angular acceleration and linear acceleration). These values are converted into a z-score. If the z-score is above 80th or 90th percentile, then the sensor triggers an alert on the phone (via a SMS) or via locally installed blinkers or hooters," Dr. Varun Dutt, the leader researcher and Associate Professor at Indian Institute of Technology, Mandi, Himachal Pradesh told Indian Science Journal.
The portable sensor can detect a change in linear displace of 0.3 mm with a 5 percent or less false-alarm rate and close to 99.99 percent hit rate, Dr. Dutt said.
How does it work?
Dr. Dutt said, if there is an angular movement of 0.2 degree or more, then the local alert via hooters and blinkers would be instantaneous. However, if there is a linear (slipping) movement of 0.3 mm, then the local alert will get fired at a maximum of 8 seconds of the movement. The global alert (via SMS) would also go with the triggering of the local alert.
The system could monitor prevailing weather parameters (temperature, pressure, relative humidity, barometric pressures, light intensity, wind speed and wind direction) as well as prevailing soil parameters (soil movement, soil moisture, and soil stress). Thus, the system could be used as a weather station as well as for monitoring of movement in built structures as well.
Dr. Dutt said, they have evaluated the system first in lab settings and then in field settings to study its efficacy. The system has already been deployed at several locations in Mandi district of Himachal Pradesh and Nainital district of Uttarakhand, while deployment in more locations is in the pipeline. They have launched a start-up company for commercialising the system, which is being incubated by IIT Mandi.
he system developed by Dr. Dutt and his team costs a fraction of the cost of available system internationally. A conventional landslide monitoring system installed by Amrita University, Coimbatore (Tamil Nadu) in Munnar, Kerala costs a whopping Rs. 5 crores (approximately $7.0 million), whereas the one developed IIT Mandi costs just Rs. 35,000 ($ 488) for weather and soil parameters.
"If we assume that 50 lives are saved by the system, then the cost-effectiveness of our system is Rs. 700 (less than $10) per life saved (this calculation assumes that a single system deployed at a landslide location saved 50 lives)," said Dr. Dutt.
Each unit is independent and connects to the Internet using an existing GSM (mobile) network. Once a unit is connected to the Internet via mobile network, it can send its data to a remote computer in the cloud.
From a single unit, one can have multiple sensors deployed in soil where these sensors are deployed in a circular area of around 10 meter to 15 meter radius. In addition, the local warning pole on the road is indeed linked to all deployed systems via radio frequency – so any deployed system can trigger a local warning on the road due to movement. Also, each system on its own has the ability to send a SMS to mobile numbers when significant movement occurs.
The researchers said, though the sensor was developed specifically to alert soil movements/landslides, its technology could be developed to other applications like monitoring built structures and prevailing weather.
Image courtesy: Dr. Varun Dutt