Applied Mechanics and Materials Vols. 397-400

Abstract: In this paper, by researching the wireless sensor network, combination of the zigbee wireless communications protocol features,using the Wireless sensor technology to establish the Tibetan wetland protection program. Combine the characteristics of Tibetan areas about wetlands, finally work out a reasonable set of Tibetan wetland model. The model data is obtained through a variety of sensor nodes, using wireless transmit data to Host computer. Host computer use the Socket communication protocol sent to the server. After Server processing ,displayed by Web form.The model have tested int wetlands, and also got a series of data results,and the resul display a number of environmental problems.

Abstract: In order to meet the testing accuracy of torque in the test of biological bone tissue torsion behavior, a strain gauge torque sensor based on multi-beam structure is designed. The mechanical model of the torque sensor is given and the parameters of the elastic beam structure have been optimized by finite element analysis. Finally the material of the structure and processing technology are determined and static calibration is carried out. Experimental results show that the linearity is 0.9% and the sensitivity is 0.14mV/V in the measurement range from 0 to 0.5Nm with 0.3% resolution.

Abstract: The design of the angular displacement sensor based on magnetoresistive technology uses DSPIC30F3010 digital signal processor for computing. Having been amplified, magnetoresistive element output signal enters into the single-chip microprocessor A/D converter unit to operate together with the Hall components output signal operation processing, and ultimately generates the actual angular displacement values.

Abstract: Design of large-stroke linear displacement sensor with high-precision based on SS495A1 technology uses permanent magnet as the excitation source and a series of linear Hall devices as the sensing element. Having been encoded, linear Hall device output signal enters into DSPIC30F3011 A/D conversion to do conversion, and obtains the absolute displacement value after DSPIC30F3011 calculating, and then transmits to the host computer via RS485 to achieve the non-contact, absolute measurement of the linear displacement. The sensor shell and seal have special materials and special processes so that it can function stably under water, especially in the marine environment.

Abstract: A dual demodulation technique based on tilted grating and InGaAs photodiode array is proposed; using the coupling modes of the cladding, a wavelength demodulation method with the tilted grating as the spectroscopic device is realized. This method can achieve that the demodulation of the channel in which the sensing information changed and the optimization of collection rules of the system. Two tunable F-P filters scan and demodulate the sensing path simultaneously to further improve the system response speed. Simulation analysis and experiments results indicate that the average demodulation time is 40ms and the average signal frequency can reach 15Hz. In addition, the demodulation bandwidth is 40nm, and its wavelength demodulation precision can reach 20pm. The system has advantages of the shorter delay time, and the demodulation time is immune to the number of channels, etc.. Therefore, this system is able to meet the smart requirement of some complex systems and large scale distributed intelligent system.

Abstract: This paper focused on the same bottom set of field devices, and designed two kinds of field-bus control system, one is PROFIBUS, and another is the Interbus. Applied the OPC technology to realize the information exchange between two bus systems, and applied the PC configuration software, to monitor equipments on the spot. The whole monitoring system included the monitoring program and OPC server program. The monitoring program is no longer included with the specific hardware communication part. The communication monitoring program and hardware are realized by OPC server software, when the system needs to be modified, only need to modify the OPC corresponding part. If the system needs to expand and communicate with the outside world, just need to expand the OPC. After many times field operation, proved the monitoring system of two OPC bus technologies was stable, reliable, and timely control reaction.

Abstract: The monitoring and control system based on CAN bus was designed in order to implement the data reliable transmission between all nodes in the control system of the vehicle-mounted rig. Firstly, the hardware structure of the monitoring system was designed in the paper, and two CAN network was built, which one CAN network used CANopen protocol and the other used J1939 protocol and CAN2.0B protocol, that it saved the resource of hardware and software. Secondly, all CAN protocols , program flow chart and software with Labview were designed in detail. The application results of the actual engineering showed that it realized the function of data transmission with each console and real-time monitoring.

Abstract: A novel size-shifting measuring method for multi-diameter shaft grinding is presented. The principle of size-shifting measuring method is to automatically switch the zero positions of multi-diameter shaft in grinding process. Each steps zero position of the sample part and magnification of the gage head are measured before grinding. The measured values of all these steps are controlled within the gage head measuring range by auto-compensation, so that the grinding process of multi-diameter shaft can be accomplished with only one-step installation and non-stop. The size-shifting software of the function is programmed, and the hardware circuit is designed for active measuring instrument. The experimental measurement on the basis of active measuring instrument is carried out to demonstrate the validity of this suggested method. This method has such advantages as operational simplicity, high efficiency and reasonable accuracy. At the same time, the research result is beneficial to further improving the active measuring instrument.

Abstract: Overpass is the major transportation facilities in the city, and occupies a very important position in the urban road network. Rainfall can likely cause surface water under the concave overpass. We establish a concave overpass wanter depth monitoring sandbox based on Internet of Things, and simulate the concave overpass water depth with different rainfall level. Simulation results show that the concave overpass wanter depth monitoring sandbox can control the overpass water depth with controlling drainage opening time by adjusting the threshold value, and simulate the physical environment very well. This can interchange for the city flood control and drainage design, checking provide reference and basis.

Abstract: A real-time die swell data gathering system was developed based on laser diameter gauge in order to measure the die swell of the viscoelastic materials. Software of the system is compiled by C language. Data gathering, date display, data saving and date analysis were realized. Experimental procedures were established, by which the die swell can be acquired. The laser gauge is put 5cm under the die of self-developed multi-function and all-electric rheometer (MAR) to measure the diameter of the extrudate. The rheological behaviors of the PP/PS blends are tested. The change laws of the melt die swell ratio in the condition of different frequency and amplitude were obtained. Compared with the steady-state extrusion, after introducing vibration force field, the melt die swell ratio decreases obviously. The die swell ratio of the blends decrease in fluctuation state with the increase of the frequency; while decreases gradually with the increase of the amplitude. In addition, with the die length-diameter ratio increases, die swell ratio of the blends decreases gradually.