Summary: | 碩士 === 國立成功大學 === 太空與電漿科學研究所 === 106 === The single-axis velocity analyzer, SAIV, a simplified IDM, is capable of simultaneously measuring the ion density and 1-D ion drift velocity, as one of the sensors in the space plasma instrument package Mesosphere and Ionosphere Plasma Exploration complex (MIPEX) is going to be installed onboard a university-based hybrid sounding rocket, to investigate the electrodynamic processes in the D, E layers of the ionosphere above Taiwan will be reported.
The original design of the IDM is modified by reducing the number of collector segments from four to two, to reduce the data rate and to increase the SNR, the single-axis ion drift velocity is derived. With information about the attitude and velocity provided by other rocket sensors such as inertial measurement unit (IMU), magnetometer and GPS receiver. 2-D Ion velocities can be furtherly constructed from one full spin of the rocket. In this work, the design concept, performance analysis by simulation, hardware development and in-lab experiment of the SAIV is presented.
In a practical measurement, the trajectories of the incident ions are easily affected by the potential supplied by the grids in the sensor. To investigate this effect and to estimate the error, the trajectories of the ions are comprehensively simulated by the SIMION software with different incident angles and ion energies. The results show that the ions with lower energy are easier to be bended and have more contribution in the measurement error. The functionality and performance tests of SAIV are verified by experiments in the space plasma operation chamber, and the results agree with the simulation and it indicates that this sensor SAIV satisfies the requirements of the sounding rocket mission which is scheduled to be launched in 2020.
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