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Objectives: To design Micro Electro Mechanical System (MEMS) based sensor with novel design considerations to detect/ identify PhotoPlethysmography(PPG) signals when the person is in dynamic mode. To simulate the above design using COMSOL Multiphysics and evaluate the results with the existing methodologies. Methods/Statistical Analysis: A MEMS based sensor with a four T-shaped cantilever with middle load hanged structure is designed in COMSOL Multiphysics and after attaining the required resonant frequency of PPG, by using capacitive actuation technique the acquired mechanical signals are evaluated and digitised. Findings: PPG sensors optically recognize changes in tidal volume of blood (i.e., changes in the force of light perceived) in the vascular bed of little scale tissue by reflection from or transmission through the tissue. If the person is in static mode it is very easy to detect blood flow rate. If suppose the person is not in rest, i.e., may be dynamic we will observe many variations in blood flow rate. So it is very difficult to estimate the blood flow rate. This Patch type device easily measures the blood flow rate. Application/Improvements: Mainly these type of devices are useful to detect variations in blood flow rate in human whether in static condition or in dynamic condition. In future we are planning to develop implantable sensors with reporting system to doctor in particular intervals of time. This may be helpful to doctors to cater the needs of human society at right time whenever it is needed

In this paper, we have proposed a novel structure in Micro Level to detect Parkinson's Disease at early stage. We have designed the proposed structure using FEM tool i.e Comsol Multi-Physics by utilizing capacitive actuation technique. The Simulations are done on capacitive based micro structure by changing the proof mass of the material. It is observed that PTFE material of the proof mass with silicon legs by giving specific dimensions are showing best optimized results. This results shows high sensitivity, high reliability and cost effectiveness of the proposed PD Sensor.

Colorectal tumor is the third most regularly analysed malignancy and the fourth driving reason for growth demise in both men and ladies in India. The Indian Cancer Society estimates that 3,79,100 individuals will be determined to have colorectal malignancy and 49,190 individuals will die from the disease in 2018. Traditionally, colon tumor is analysed utilizing infinitesimal investigation of histopathological colon tests. We present a method of detecting Human colorectal carcinoma cells in blood. Cells experience duplication and separation inside multi-cell living beings. The portrayal of physical properties of cells, for example, their mass and solidness has been of awesome intrigue and can have significant ramifications in cell science, tissue engineering, and disease research including cancer. The mechanism of duplication will increase the mass of the infected cells in the blood. In our study, we identify the change in mass of the carcinoma cells in the blood by observing the change in Eigen frequency of the cantilever beam.

Background/Objectives: This paper presents the design and simulation of MEMS microcantilever sensor for the identification of Mycobacterium tuberculosis in the given blood sample. Method/Analysis: The surface of the microcantilever is covered with TB antibodies which are specific to TB antigen 85complex. When the blood sample containing tuberculosis bacteria is placed on it, biochemical reactions occur between TB antigens and the antibodies on the surface of the microcantilever. This gives a deflection to the microcantilever from which TB can be detected. COMSOL Multi Physics is used in the design of micro cantilever. Findings: Presently the most general method for diagnosing TB is the sputum smear microscopy in which micro organisms are observed under a microscope. In some of the advanced countries culture methods are used to detect TB. At present TB identification method requires a period of 4 to72 hours and is not so accurate. Hence there is a need of MEMS sensor which offers quick and accurate method to detect Mycobacterium tuberculosis . When the patient’s blood sample is placed on the microcantilever, the antigen-antibody interaction causes it to bend and the adsorb molecules generates a surface stress on the microcantilever. This stress is created due to the interactions between the molecules and the microcantilever surface. It has been observed that the deflection of the micro cantilever is high for a length of 20μm and for a width of 5μmkeeping the other parameters constant Application/Improvements: Using this MEMS bio sensor, tuberculosis disease can be identified very accurately and speedily comparing to existing methods.

Micro Electro Mechanical System (MEMS) is the promising technology in bio-medical engineering which reduces the cost, sensitivity and accuracy of the devices. A Novel structure is proposed using MEMS technology in this paper. The structure comprises of a proof mass which is movable and four arms or limbs with a torus of 900 revolution angle. The four edges of the torus are fixed. A fixed plate is kept on the top of the proof mass to measure the capacitance and output voltage of the proposed MEMS sensor. The sensor is designed for a value of 0.4g to 0.8g. The simulated values are correlated with the theoretical values. The proposed design accurately measures tremor frequency which is in the range of 4Hz to 7Hz. The proof mass in the structure moves up and down when the device is attached to finger tip of the patient because the resting tremor or pill rolling tremor is the preliminary and basic detection symptom of Parkinson’s disease. When the structure is connected to fingertip, variation in Eigen Frequency, output voltage and capacitance is measured. An amplifier is designed with a gain of 103dB and verified with the voltage so obtained from the output of the proposed sensor is 100 milli volts. There is a variation of 5% change in capacitance from theoretical to simulated values. Similarly, 8% variation in voltage. The displacement sensitivity is increased by 10%. The design is simulated using FEM tool COMSOL Multiphysics.

In this paper, the analysis of narrow wall of standard X-band coplanar waveguide slot arrays has been carried out. Small inclined slots from broadside cannot be accommodated for their resonant length, as the narrow wall dimension is smaller than λ g/2. However, the different slots of arrays of practically possible lengths are considered and obtained the sum and difference patterns. The data is presented in the results of waveguide slot arrays for satellite tracking radar systems.

This paper represents the design and analysis of energy harvester using MEMS based cantilever with PMN-PT single crystal properties which has excellent piezoelectric properties while compared to other piezoelectric materials like PZT thick film. The design is analysed using COMSOL multi physics which is used for many MEMS operations and also problems related to physics with many mathematical calculations with better efficiency and ease to design. We designed a cantilever with PMN-PT properties which has good coupling coefficient and increased perforations in number in form of square and circular. We tested the displacement sensitivity i.e., the variation of displacement at different eigen frequencies with increase in number of perforations. We observe output voltage by designing electromechanical analysis and variation in output capacitance of 2 .41 x 10-22 Farads is observed.

In this paper the design and modeling of capacitive shunt switch for k-ka band applications is presented. The proposed model for this design is the crab leg flexure. In order to reduce the squeeze film air damping, the perforated switch with reduced spring constant is designed. Analysis of designed switch has been carried out on the various parameters of the switch such as damping factor, switching time, quality factor and Eigen frequencies in order to design a reliable switch. The results indicate that the obtained pull in voltage is 3.1V for the dielectric gap of 1mm and spring constant of 2.95N/m2. Switching time is observed as 1.2ms and 2.15ms for the gap of 1mm and 1.5mm respectively. The capacitance ratio i.e. Cdown/Cup is 211.11 for HfO2 and 100.741 for Si3N4. Resonant frequency is obtained as 14.45 KHz. Return loss is calculated as-44.85dB at a frequency of 1GHz and -25.68dB at a frequency of 27.5GHz and insertion loss is obtained as -0.0447db at 1GHz and -1.0379dB at 27.5GHz. The maximum peak isolation is observed as -59.5dB at 1GHz frequency and -71dB at 27.5GHz frequency.

Emerging sciences have brought tremendous changes in the electronic world. One such revolutionary technology is MEMS. MEMS extend their implementation into many sectors like mechanical sensors, micro fluids, medical implants, bio-MEMS. In this paper, we discuss the design of a Micro Bio-sensor which senses the capacitance fluctuations materialized in it by various reactions of antigen and antibody. It is a cantilever based structure which is coated with a drug that is responsive to Carcino Embryonic Antigen (CEA), which is considered to be a first level indicator of colon cancer present in human body. The presence of this disease causing element in the blood initiates the antibody-antigen interactions which induces changes in the electrical parameters of the sensor device. These changes are utilized to determine the severity level of pathogens present in the patient’s blood.