Papers by Author: Ting You

Abstract: With the rapid development of marine transportation industry, biological fouling not only affects the speed of navigation but also highly increases fuel consumption. In the paper, a novel hydrogel-based fouling release coating is developed to address the issue by a combination of non-stick property with a low surface tension of the coating. A hydrogel-based silicone fouling release coating was synthesized and two kinds of different intermediate coatings were studied to give a proper match as the tie layer between the substrate coated with primer and the hydrogel silicone on the surface. The adhesion strength, surface tension as well as surface topography of the fouling release coating were studied. The corrosion resistance and anti-fouling performance of the substrates sprayed with the coating were characterized by salt spray test and immersion test in a simulated marine system. The results show that the adhesion between the substrate and the fouling release coating is grade two measured by grid test. The water contact angle of the coating is 104.8o and Rz of the coating is 10.71μm. The specimen is intact after 1000 hours under salt spray test. No diatom was found settled on the specimens in a simulated static marine system while a little diatom was observed on the specimens in a simulated dynamic marine system. It has been found that the intermediate coating comprising of epoxy resin gives proper match between the primer and the fouling release coating consisting of PDMS resin. The coating exhibits superior anti-fouling performance under stationary state.

Abstract: Acoustic emission is generally high-frequency signal with the characteristics of broadband and burstiness, so it is very difficult to acquire acoustic emission signal in real time as well as rapidly, In this paper, an USB based acquisition system for acoustic emission signal is designed, which adopts CPLD as controller and uses two high-speed A/D converters to achieve synchronous acquisition of two-channel acoustic emission signals, The system first puts collected data into a FIFO and then transfers data to host through USB using CY7C68013, The sampling frequency of the system is up to 10MHz and the transmission rate of USB is 40M/S, Hard body impact test and lead-breaking test indicate that the system can achieve real-time acquisition of acoustic emission signal well,

Abstract: This article raises an improved program of adding Pseudo-Satellite’s pseudo-range measurement and setting best configuration for Pseudo-Satellite in mentioned program on the basis of existing Binary System [1]. Through comparison and analysis of improved Tri-satellite System and existing Binary System, this article proves that it shortens location time and location precision by adding Pseudo-Satellite to Binary Navigation Location System. Finally this conclusion is approved by simulating Mathematical model using software.

Abstract: For optimal control of synchronous machine, chattering phenomenon will appear if traditional slider control is adopted because permanent magnet synchronous machine is a complex nonlinear time-dependent system with strong coupling of current and rotational speed to cause the deterioration of system control performance with load or load disturbance. In this article, based on the mathematical model of permanent magnet synchronous machine, a control system for it, which combines sliding mode control and active disturbance rejection control, is proposed to improve the dynamic performance and robustness of control system. In the control system, sliding mode control is adopted to control the inner current of machine and active disturbance rejection control is adopted to control the outer speed. The load disturbance of system is also estimated and offset. The results of matlab simulation show that the control system can eliminate serious chattering phenomenon existing in sliding mode control, improves the robustness of system for load and system parameter disturbance as well as has great dynamic and static performance.

Abstract: The grinding wheel wear status is an important guarantee for the processing efficiency and processing quality of precision and super precision grinding. In this paper, a USB acoustic emission signal acquisition system is designed for online monitoring of grinding wheel status. In the system, CPLD is used as the controller, and a high-speed A/D converter is used to implement the synchronous acquisition of acoustic emission array signals. The collected data are sent into FIFO, and CY7C68013A is used for USB data transmission with upper computer. The sampling frequency of the system can be 10 MHz, and USB transmission speed can reach 40M/S. It is proved that it can meet the monitoring requirements of grinding wheel wear status well by the grinding processing.