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The dome-shaped membrane was designed for the fluidic based flow sensor for the underwater sensing. It has the diameter of 5mm and thickness within 0.2mm. The simple fabrication process for the dome shaped structure was demonstrated using casting and molding processes. The effect of the fabrication process was investigated by measuring the thickness of the dome-shaped membrane for different sample. For the performance analysis, the actual shape which was the same with the fabricated shaped was simulated and compared with the ideal shape using finite element analysis for the same input flow rate. The membrane sensitivity of the actual shape decreased from 163.4 μm/ms-1 to 133.33 μm/ms-1 compared to the ideal shape based on the displacement of the membrane over input fluid velocity.

The dome-shaped membrane is very important part of the micro/nano devices. The dome-shaped with the thickness of 150 μm and a radius of 3.2 mm was fabricated using the soft lithography process. The Polydimethylsiloxane (PDMS) was selected as a material because it deformable and suitable to implement as a membrane. Soft lithography is based on pattern transfer using a mold that is patterning the substrate material. In this paper, two techniques were suggested to fabricate the dome-shaped membrane which are reflow technique and stamping technique. The comparison was made for both techniques using a Scanning Electron Microscope (SEM) and it seems the stamping technique has an advantage where the uniform thickness of the dome-shaped membrane can be achieved. The discussion on the temperature effect of a stamping technique shows that the suitable temperature to harden the PDMS is in temperature room where the bubbles can be eliminated under this temperature.

The performance of a thermoelectric power generator for powering wireless sensor node has been studied and evaluated. This study covers the results obtained from two configurations of thermoelectric cell with heat source temperatures range from 40 to 230 °C. It was found that the highest output voltage is 9.08 V belong to configuration B with two parallel thermoelectric cells. This configuration was capable to power up sensor node compared to configuration A with the lowest heat source temperature at about 200 °C. To enhance the capability of the configurations, DC boost converter circuit has been developed and tested. By connecting to the DC boost converter, configuration A can power up the wireless sensor node with heat source temperature at about 220 °C while the minimum heat source temperature for configuration B was reduced from 200 to 170 °C. This study identified the optimum operation condition to power up wireless sensor node by thermoelectric power generator for remote application and make conclusion as to how to increase the performance of thermoelectric power generator by introducing DC boost converter.

Multi-sensor data fusion provides significant advantages over single source data to achieve an improved accuracy and better precision. Decentralized data fusion approach is one in which features are extracted and processed individually and finally fused to obtain global estimates. The paper presents decentralized data fusion algorithm using factor analysis model. Factor analysis is a statistical method used to study the effect and interdependence of various factors within a system. The proposed algorithm fuses accelerometer and gyroscope data in an inertial measurement unit (IMU). Simulations are carried out on Matlab platform to illustrate the algorithm.