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The development of thermoelectric device engineering has begun with the exploration and innovation of the use of new materials, defect engineering, doping engineering, and material mixing experiments. In previous studies, modifications have been made to the GO/rGO thermoelectric by doping with atom S but in previous studies have not conducted research on other atomic doping and the influence of doping concentrations. In this study, graphene oxide-based thermoelectric devices were doped by phosphorus and nitrogen atoms and modifications to the width of rxGO in the xGO /rxGO pair to get different areas. xGO materials were synthesized with added ultrasonic wave technique from graphene oxide material, then deposition to polyimide substrates. The fabrication process was done to form PGO/rPGO line modification of 0.5/0.25, 0.5/0.5, 0.5/0.75 mm and NGO/rNGO line modification of 0.75/0.75, 0.75/1.00 mm for using irradiation laser technique with length wave 405 nm and power 1.5 W. The characterizations used are X-Ray Diffraction, SEM, Temperature sensor and I-V. The voltage comparisons result of modification rPGO width line dT=10K were rPGO line width 0.25 mm>0.5 mm>0.75 mm (0.201, 0.165, and 0.126 Volts) Volt, as well as the seebeck coefficients comparison result were rPGO line width 0.25 mm>0.5 mm >0.75 mm (3.33, 2.95, 2.18) x 10−4 V/K. The voltage comparisons result of modification rPGO width line dT=10K were rNGO line width 0.75 mm>1.0 mm (0.47 and 0.4) Volt, as well as the seebeck coefficients comparison result were rNGO line width 0.75 mm>1.0 mm (2.52, 2.47)×10−2 V/K. [ABSTRACT FROM AUTHOR]

Applications of quadcopter or hexacopter have helped many scientists and engineers find lots of easiness for survey purposes, particularly in terms of accelerating data collection with high accuracy. For the unmanned aerial vehicles (UAV) to be performing that kind of superior characteristic, direct-current brushless motor plays a very crucial role. In commercial UAV, the brushless motor obtains electric current from lithium-polymer batteries after being handled by an electronic speed controller. Despite the fact that the position of the motor is already sensed, the electric current response in the brushless motor due to applied voltage is also important to detect. This very-careful electric current detection will provide flight controller more detail information regarding the brushless motor performance. In this present study, a Hall- effect based non-contact sensor SS49E form measuring the electric current is introduced. Taking into consideration that small fluctuations of the electric signals sometimes cannot be detected by the Hall sensor, we then increased the magnetic flux by means of inserting half-circular toroids. Our experiment revealed that the approach was effective in such a way that almost all electric signals can be then recorded by the sensor. In addition, the phase modulation and speed-controlled data collection and analysis provided fundamental information that can be used by the flight controller for the more complete algorithm to increase the UAV performance. [ABSTRACT FROM AUTHOR]