K. A. Unnikrishna Menon

Voltage intensity based non-invasive blood glucose monitoring

Diabetes is one among the supreme health challenges of the current century. Most common method for estimation of blood glucose concentration is using glucose meter. The process involves pricking the finger and extracting the blood along with chemical analysis being done with the help of disposable test strips. Non-invasive method for glucose estimation promotes regular testing, adequate control and reduction in health care cost. The proposed method makes use of a near infrared sensor for determination of blood glucose. Near-infrared (NIR) is sent through the fingertip, before and after blocking the blood flow by making use of a principle called occlusion. By analyzing the variation in voltages received after reflection in both the cases with the dataset, the current diabetic condition as well as the approximate glucose level of the individual is predicted. The results obtained are being validated with glucose meter readings and statistical analysis of the readings where done. Analysis shows that the bias as well as the standard deviation decreases as the glucose concentration increases. The obtained result is then communicated with a smart phone through Bluetooth for further communication with the doctor.

Power optimization strategies for wireless sensor networks in coal mines

Coal continues to be mined in over 50 countries. Coal accounts for approximately 64% of Indias electricity. Spontaneous explosions in the coal mines are one of the most common accidents. The main cause for mine explosions is the presence of toxic methane gas in an environment with insufficient oxygen. Gas detection is crucial for explosion prediction. Currently gas monitoring in coal mines is not so reliable. This paper introduces the use of a wireless sensor network (WSN) with gas sensors to predict methane outbursts in coal mines. This research work has developed an Early Warning System (EWS) deployment in the complicated environment of mines as low cost and power efficient wireless sensor network nodes have been designed to substitute the traditional wired and fixed monitoring equipment. The system can thus reduce the impact of mining explosions by facilitating the timely evacuation the miners from the areas of highest risk by providing an early warning and alarm system. Special attention has been paid to the WSN power optimization design strategies that include: using low power components, only sending the minimum amount of data (with efficient data acquisition protocols and data aggregation protocols), appropriate configuration of nodes (with clustering protocols) and automatic timely variation of power consuming states (with state transitions of listening, sleeping and transmitting modes).

Wireless sensor network for river water quality monitoring in India

Water is an important natural resource which needs constant quality monitoring for ensuring its safe use. This paper introduces a river water quality monitoring system based on wireless sensor network which helps in continuous and remote monitoring of the water quality data in India. The wireless sensor node in the system is designed for monitoring the pH of water, which is one of the main parameters that affect the quality of water. The proposed sensor node design mainly comprises of a signal conditioning module, processing module, wireless communication module and the power module. The sensed pH value will be wirelessly transmitted to the base station using Zigbee communication after the required signal conditioning and processing techniques. The circuit for the sensor node is designed, simulated and the hardware prototype is developed using the appropriate components which minimize the power requirement of the system and provides a cost effective platform for monitoring water quality.

Wireless power transfer to underground sensors using resonant magnetic induction

Wireless communication systems play an increasingly integral role in society. Currently underground sensor networks are used in many applications for security purposes, environmental applications, infrastructure maintenance etc. The major problem, associated with sensor networks, is in providing the power supply to enable the networks to work for long durations. This paper presents a novel technique to wirelessly, supply power to the underground sensor networks using the magnetic induction principle. In addition, using the resonating principle further ensures maximum efficiency of this proposed system. Experimental results to prove the feasibility of this novel technique for supplying wireless power are presented.

Efficient wireless power transfer using underground relay coils

Underground Wireless Sensor Network (UWSN) is a newly emerging technology that is capable of replacing existing traditional wired connections. Research has proved that magnetic induction based communication performs better than electromagnetic wave communication, especially in the dynamic underground environment. Currently, data recorders are being used to collect the data from underground sensors. Data recorders have a few disadvantages such as the inability to produce data on time and the difficulty to deploy them. Many problems related to data recorders can be solved using UWSNs magnetic induction technique. One of the main challenges associated with the UWSN is the lack of efficient power transfer to underground sensors as the distance between the transmitter and the receiver coils increases. This paper introduces a unique technique where relay resonators are used between the transmitter and the receiver coils to increase the efficiency for charging sensors which are present underground. Experimental results that prove the presence of relay coils for efficient power transfer are presented.

Consensual and co-ordinated vehicular headlight attenuation using wireless sensor networks

Driving at night causes approximately 50% of traffic fatalities; one of the primary causes being the usage of headlights on high beam. Courteous drivers usually lower their headlights from high to low beam when they see oncoming traffic. However, due to driver inertia, either inherent and/or caused by frequent switching between high and low beams, headlights are eventually left in high beam. This causes temporary blindness in drivers from on-coming traffic, leading to accidents, as well as permanent blindness in frequent nighttime drivers. In this paper, we propose a novel system to automatically attenuate the headlights of oncoming traffic and thereby reduce driver discomfort. We use a consensual and coordinated communication approach in order to request oncoming traffic to lower their headlights to low beam when necessary and lower our own headlights as well. Experiments conducted show that it is possible to automatically attenuate light intensity from on-coming traffic in fractions of a second, at significantly large distances, thereby reducing driver discomfort and mitigating accidents significantly.

Energy efficient clustering protocol for early warning system for miner's safety in coal mines

Early detection of spontaneous explosions in coal mines can be made possible by monitoring the concentration of toxic gases such as Carbon monoxide (CO), Methane (CH4) and Hydrogen sulfide (H2S). Methane gas detection is very important for outburst prediction. In order to protect people and to avoid destructive sequence, it is necessary to design a system that can predict methane outburst in coal mines. In order to improve the reliability of gas monitoring in coal mine, we design a wireless sensor network (WSN) with gas sensors. The wireless sensor network is suitable for toxic gas monitoring in the severe environment of underground coal mines. Semiconductor type methane sensor having low power consumption and high sensitivity is used in the proposed system. The chain type clustering of low power sensor nodes along with data aggregation is devised to optimize the power consumption by the WSN. Additional feature of minimum data transmission and state transitions between listening, sleeping and transmitting modes in sensor nodes also guarantee power optimization.

Underground Tunnel Detection Across Border Areas

Tunnels are considered as the oldest method of passageway. Underground tunnels are popular from olden eras for connecting places, travelling, and aid for various surface threats. They are also used for illegal activities like smuggling of unlicensed drugs, weapons, currency, gold, explosives, and even human trafficking is being done through these tunnels. These immoral activities are concentrated in national border areas in order to escape from the border security measures. Hence the detection processes of such tunnels in the national security border areas are necessary in order to protect our homeland security systems. The geology plays an important role in the detection of the underground tunnel system procedures. There is no perfect system for the tunnel detection and localization and even today the tunnels revealed in coincidence. The basic principle to find the hollow space (tunnel) is, by sending an ultrasonic frequency signal into the ground, and study the reflected beam from the tunnel or the hollow space. By analyzing the reflected signal characteristics, preliminary detection of a tunnel/void is possible. Basic idea of the detection is to perform the range estimation algorithm (REA) by pulse echo method. From these, we can estimate the depth of the tunnel. The characteristics of the signal at the soil-tunnel (air) reflection interface are to be investigated.

Inductively Powered Underground Wireless Communication System

Underground Wireless Sensor Network (UWSN) is a newly emerging technology that is capable of replacing existing traditional wired connections. Research has proved that magnetic induction based communication performs better than electromagnetic wave communication, especially in the dynamic underground environment. Currently, data recorders are being used to collect the data from underground sensors. Data recorders have a few disadvantages such as the inability to produce data on time and the difficulty to deploy them. Many problems related to data recorders can be solved using UWSNs magnetic induction technique. Some of the main challenges are efficient power transfer and communication to underground sensors when distance between transmitter and receiver coils increases. This paper introduces a unique technique where both wireless power transfer and communication are achieved simultaneously for sensors which are present underground. A high frequency square pulse is used for inductive power transfer between transmitter and receiver coils. The same square pulse is pulse code modulated and is used for wireless communication between the transmitter and the receiver coils with a suitable data rate. Experimental results to prove the feasibility of this novel technique for concurrent wireless power transfer and communication make the paper different from its counter parts.

Simulation framework for modeling magnetic induction based wireless underground channel

Wireless underground communication is a challenging task when electromagnetic (EM) waves are used. The communication has to face many limitations like spreading loss, fading, and attenuation. The existing solution for this problem is magnetic induction (MI) based communication. The performance of this method depends on many factors like the distance between the transmitter and receiver, placement of relay coils, moisture content, permeability, seasonal changes, and the depth at which the system is deployed. There are no proper MI channel model which incorporates all these soil parameters and geometrical parameters for predicting the signal quality at the receiver. We propose a simulation model using MATLAB to predict the signal quality at the receiver by optimizing the placement of relay coils, taking into consideration the soil parameters, geometrical parameters of coils, and geological parameters.