Yiyong Huang

Contact analysis of flexible beam during space docking process

This paper mainly focuses on the impact contact problem during docking process of flexible probe. The docking dynamic model based on flexible probe is developed with the help of Lagrange analytical method. The modal equation of flexible rod is derived with the effect of the rigid counterweight considered. The contact models of docking impact in both normal and tangential directions are presented in detail. The time history of impact contact force, the shape and size of contact area, the distribution of contact stress and local deformation, and the effect of structural flexibility to the contact surface are discussed based on the theoretical model. Moreover, the ground-based docking impact experiment is conducted to verify the theoretical results.

Analysis and design of parameters in soft docking of micro/small satellites

Although substantial research has been conducted on the soft docking problem, the design of the docking mechanism is always conducted using experience. The challenge for conducting factor analysis and design lies in an accurate theoretical model, and the evaluation criteria of a successful docking. In this paper, the soft docking model of micro/small satellites is proposed using an analytical method and validated using a commercial FE package. The evaluation criterion of a successful docking is defined by considering the operational principle of the capturing mechanism used in micro (or small) paired satellites. The effect of the parameters on the soft docking result is discussed and their value domains are designed based on our proposed criteria of a successful docking.

The Measurement of Dynamic Pressure in Tank During the Compression Process

The measurement of dynamic pressure is quiet different from that of static pressure. It depends on the frequency resonance characters which are first discussed in this paper. It is obvious that the output of the measured dynamic pressure is no long proportional linearly to the input with the static sensitivity. The amplitude and the phase of the output both vary with the frequency of the pressure and the natural frequency of transducer. The analysis gives some guidance to us how to select proper sensor for practical need and how to improve the performance of the sensor under the given amplitude error. Besides, when the transducer is not flush with the tank wall but connected to the storage tank by a long narrow lead-in tube, a correcting model is presented which shows that the transducer measured pressure differs from the pressure in the tank. The transducer acts as a spring and the liquid in the tube as a mass. Further, this work is compared to the experiential computing equation and the difference is illustrated.

Notice of Retraction Simulation of heat transfer and mass transfer in cryogenic propellant tank slight volume compression

A cryogenic liquid quantity gauge for low-g application is described, named the Compression Mass Gauge (CMG), operates on the principle of slightly changing the volume of the tank by an oscillating bellows. The resulting pressure change is measured and related by thermodynamics to the volume of vapor in the tank, from which the volume of liquid is computed. The mathematical model of propellant tank with slight volume compression process is built. The mass transfer and heat transfer models among gaseous proportion and cryogenic propellant are projected in order to obtain the variation laws about the parameters, such as pressure and temperature in the gaseous proportion, propellant flux of volatilization, tank wall temperature and so on. Differential equation group is comprised of actual gas state equation, conversation of energy equation, mass and heat transfer equations. The differential equation group is calculated by the means of four steps Runge-Kutta Method. The effect of the compression volume and propellant flux of volatilization to the parameters in gaseous proportion is discussed.