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In this study, design and analysis of a robotic mechanism, able to traverse low diameter pipes for inspection, maintenance or doing special tasks, has been addressed. Using a mechanism able to move properly along pipes with different diameter while having appropriate adaptability when passing complex routes or bends is so important. So, in this study, considering a simple mechanism based on utilizing shape memory alloy actuator, a micro-robot is designed for inspection of narrow pipes or channels. The robot has a suitable flexibility in addition to an appropriate adaptability for passing complex routes. The robot kinematics and dynamics is analyzed and dynamic equations of the robot are extracted and solved. The robot functionality in the simulation is verified through Adams and Matlab software. Finally, using a suitable controller the amount of robot traction force in addition to normal force between robot wheels and the inner surface of pipe has been measured and controlled. The simulation results predict the appropriate functionality and success of the robot in the inspection of pipes with varying diameter in horizontal, vertical or any other inclination state.

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The electrical properties of nanostructured piezoelectric materials have attracted the attention of many researchers in the last decade. These features are used in piezoelectric micro-sensors. Mechanical propulsion is usually the result of contact between a piezoelectric surface and a foreign object. In this paper, the effect of mechanical propulsion using an air wave (sound) or vacuum on a silicon diaphragm is investigated. The local stresses created on the diaphragm due to the impact of an air wave have a significant effect on the peak-to-peak voltage of the piezoelectric sensor, which can be measured by measuring changes in this parameter. To investigate this, a micromachined diaphragm of silicon was examined and it was found that fabricating a piezoelectric sensor on a thin and patterned diaphragm could increase the peak-to-peak voltage by about 1.3 times. Detection of these stresses using piezoelectric material layered on the thin and formable diaphragm can act as a piezoelectric microphone or a barometer that the presence of microstructures on the diaphragm will increase their sensitivity.