Problems in indirect measurements are associated with unknown elasticity of the momentum exchange between the exhaust plume particles and the target (Jean-Yves, 2006). If the thruster itself is mounted on the bench, it gives direct measurement of the force, but if the exhaust of the thruster is used to produce deflection, it is an indirect method (Bijster, 2014 Janssens, 2009 Zandbergen, Janssens, Valente, Perez-Grande, & Koopmans, 2010). Direct and indirect measurements are both used today, but direct measurements are given preference because of better precision in the case of micro-satellites. The sensitivity and accuracy of a thrust bench depends on its mode of measurement and the sensor itself. This, in turn, has increased the need for precise thrust and impulse measurement techniques for micro-scale thrusters and considerable effort is being invested to achieve precision (Mueller, Hofer, & Ziemer, 2010 Spence et al., 2013). The requirement for precise positioning and movement of satellites is increasing with the advancement in space technology and the last decade has seen a steady increase in interest in micro-technology. The test bench can be employed for very precise thrust and impulse measurement of micro-scale thrusters of satellites. The dynamic modeling and the design methodology can be used to design any hanging pendulum test bench and has been adopted by the Institute of Space Technology, Pakistan. A micro-scale laser displacement sensor was used to measure response of the system, and the results obtained were validated using Simulink. The theoretical system was designed using inputs from existing models. A vertical pendulum system was modeled with its governing parameters. This methodology was formulated for the design of model and parameter testing of micro-satellites at the Institute of Space Technology, Pakistan. This paper explains the development of a test bench to measure thrust between 0.1 and 1.0mN and impulse bits between 0.01 and 1mNs for micro-electro-mechanical systems (MEMS) based micro-thrusters. Conventional methods cannot be used for this purpose because the extremely low values are significantly affected by background noise. The increased popularity of micro-satellites puts great demand for precise measurement of thrust and impulse bits. Road, Lahore, Punjab 54890, PakistanÄepartment of Electrical Engineering, University of Engineering and Technology, G.T. Institutions: Department of Mechanical Engineering, University of Engineering and Technology, G.T. Authors: Haris Moazam Sheikh, Zeeshan Shabbir, Muhammad Hissaan Ali Chatha, Chaudhary Ahmed Sharif, Muhammad Hamza Waseem, Umar Asif
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