Papers by Author: Jie Xiong Ding

Abstract: In the complex high speed machining, the small segments approximated the contours curve are made up the machining path in order to satisfy the quality. It will cause break on the machine tool feed-rate, and due to limit of dynamic performance in each axis, the actual velocity will somewhat differ from the desire feed-rate, which will cause additional error on the contour. An actual feed-rate prediction model using the G-code generating from CAM system is presented in this paper, which the limits of velocities, acceleration, jerk and the case of velocity verify between segments are taken into account, the every axis actual speed and tool feed-rate, and points that programming feed-rate is not achieved in the region of its curvature mutations are calculated. The simulation results show the prediction model is efficient and can support the analysis on axis dynamic performance in high-speed machining.

Abstract: A thin sensor based on surface acoustic wave resonator (SAWR) in ZnO/SiO₂/Si structure for wireless contact stress measurement in thin gap is numerically analyzed. Firstly, the scheme of the SAWR stress sensor and surface effective permittivity for analyzing surface acoustic wave (SAW) in ZnO/SiO₂/Si structure are introduced. Then, the phase velocity and electromechanical coupling coefficient of ZnO(1µm)/SiO₂(1.4µm)/Si structure for the fundamental and first Rayleigh mode are obtained. For both Rayleigh modes, the temperature coefficient of frequency (TCF) for the structure at different frequency is calculated. Good temperature stability for the structure is achieved at frequency 1GHz for the first Rayleigh mode with averaged TCF about 0.04ppm/°C and stress sensitivity about 22ppm/MPa.