A novel design method for the micro-thrust measurement system

Abstract

A novel method is developed to determine the key parameters of a micro-thrust measurement system. Firstly, the measurement range, resolution and error of the system to be designed are regarded as the design objectives. Then, the performance parameters of the displacement sensor and the basic properties of the oscillating arm are defined as the initial design conditions. Further, according to the principle of the micro-thrust measurement, the relationships between the main design variables and the initial conditions and the design objectives are established. A criterion of maximizing the system frequency is proposed based on the invariance of generalized stiffness coefficient, and then each design variable is determined based on the above criterion Finally, a sub-micronewton thrust stand is developed using the proposed method, whose system parameters are obtained by the calibration method. The results show that the system parameters meet the design requirements, and the thrust noises corresponding to the underdamped and overdamped conditions are better than 1μN/Hz in 0.35 mHz ∼ 1 Hz band and 0.1μN/Hz in 9 mHz ∼ 1 Hz band, respectively.