Applied Mechanics and Materials Vols. 475-476

Abstract: Underwater gliders carried acoustic velocity meters can realize ocean profile observations of the acoustic velocity for long duration and large scale. This paper mainly studies the kinematics and hydrodynamics of the Slocum underwater glider carrying a acoustic velocity meter MINOSX with length 565mm and diameter 76mm. Thus, theory reference for optimal design parameters of the underwater glider is proposed. By establishing the kinematic equations and giving some related parameters, variations with time of the steady-state gliding velocity, pitch angle, gliding path and attack angle are simulated by using Matlab software; The simulation calculations of the hydro-drag and lift are completed by using Fluent software. Finally, this paper summarizes the dynamic characteristics in steady state of the underwater glider in longitudinal plane.

Abstract: It is rich in electric field energy in high voltage substations while it is hardly collected and utilized. A novel energy harvesting device based on spatial electric field is presented in this paper, which is composed of capacitive energy collector and conditioning circuit. A simulation model of the energy collector is established to study the relationship between output voltage and its structural parameters and is verified by no-load tests. There are some restraining factors such as output voltage unstable in the traditional conditioning circuit. A new conditioning circuit is designed to overcome the problems and this new circuit is more effectively. This paper designs a new device to harvest the electric field energy within substations and it can provide broad potential use in the future.

Abstract: Motor-driven on-load tap changers (OLTC) operational within power transformers are extensively used for voltage regulation in power systems, whose principal malfunctions or failures are of mechanical type. Hence, monitoring of the mechanical characteristics of OLTC is of utmost significance. Based on a rotating angular transducer as well as digital signal processing techniques, an on-line monitoring methodology is established to measure, analyze and evaluate the dynamic or transient changes of the rotating angle of the drive motor operational in an OLTC, which can effectively indicate the underlying deficiency or even potential fault of the mechanical drive system connected to the motor. Computer simulations and experiments are carried out respectively, both showing the proposed on-line monitoring scheme is feasible and applicable.

Abstract: This paper proposed a calibration method of sheet-of-light vision measurement sensor based on light plane constraint. Through capturing 12 images of different direction from homemade circular calibration target, the center of the circle and the light stripe is extracted based on Halcon platform of Germany. The experimental results obtained the intrinsic parameters, extrinsic parameters and radial distortion coefficient of the nonlinear model. At the same time the light plane constraint equation is got based on PCA plane fitting method. The results show that the calibration method is simple and reliable, and the method does not need any auxiliary adjustment. The work laid the better foundation for hard disk planeness vision measurement.

Abstract: It analyzes measuring method of working fluid conductivity on the MSWEDM through the study of the working groove equivalent circuit model and the main factors affecting the conductivity measurement. It adopts ± 18V, 50Hz AC voltage to driving the measuring electrode in order to reduce the error caused by the electric spark machining the leakage current and polarization effect; the measurement system adopts with waterproof DJS-1CF (platinum black) conductance electrode in order to reduce the error caused by the capacitance effect. It study on the working fluid conductivity measuring technology that may help lay a foundation for it can real-time, on-line control research about the working fluid conductivity.

Abstract: With the development of modern warfare, put forward higher requirements on the accuracy of the ammunition. Whether the precisely guided amunitions or ballistic correction ammunition, its working principle is derived from the accurate identification of the ballistic information. According to the research status of the present stage, the ballistic identification technology in the future is prospected, the development direction of this technology were discussed.

Abstract: Pumping station engineering field test is the main basis of pumps technical renovation and the assessment of technical and economic indicators. Flow measurement is a key content of pumping station in the engineering field test. How to choose a reliable and applicable, economic and effective measurement method and measuring instruments is the key factor of success for flow measurement. In this paper, starting from the characteristics of pumping station engineering field test technology, to research it in three aspects .They are the method of flow measurement classification, working principle and characteristics of common measuring instruments, measurement methods and the selection of instruments and equipment. It also analyzes the different types of pumping station flow measurement technologies in engineering field test, and makes some explanation combined with typical examples pumping station project flow measurement.

Abstract: TPMS hand-held diagnostic instrument to achieve the state of reading and configuration of the emitter via a wireless command, without removing the emitter from the automobile tires can complete the function of diagnostic and configuration. This paper firstly introduces the working principle of the system, and then the design of the hand-held diagnostic instrument hardware structure and software workflow is given.

Abstract: in order to understand the situation of design flood level, a water level monitoring system based on ARM7. The ARM7 high performance microprocessor LPC2132 as the core, uses the high precision AD converter TLC2543 data collection, combined with the system software and hardware design of GPRS transmission network, including the water level sensor data acquisition, remote transmission of GPRS messages, human-computer interaction module C/OS-II operating system with multiple components, the system design, to achieve the level of information the remote communication by using short message. The experimental results show that: the system to collect data of high precision, stable and reliable transmission, effectively realizes the real-time monitoring of water level data.

Abstract: Sensor networks enable remote monitoring of natural environments. For the purpose of environmentalprotection, we present a practical application of wireless networks: a remote water monitoring system based on ZigBeeand GPRS. The contents of several chemicals in the water are sensed. The sensor data are collected and transmitted viaZigBee and GPRS. Instead of focusing on theoretic issues such as routing algorithms, network lifetime and so on, weinvestigated special techniques involved in the implementation of the system while employing TinyOS, LabVIEW andMySQL.