Applied Mechanics and Materials Vols. 278-280

Abstract: Rail track surface defects detection is an important part of the monitoring of railroad safety. In this paper, rail track images obtained by detection system of rail track surface image are processed. Firstly, the Hough transform is applied to process the images of the track surface to locate and extract the image of the track surface, which overcomes the influence of incline and unfixed width of track surface images caused by vehicle vibration. Secondly, improved Sobel operator and area filter are used together to extract track surface defects from the original images. Finally, the defects images are classified based on circularity and length-width ratio of minimum enclosing rectangular of defects images.Results of experiments show that the algorithm can identify and classify the defects images of track surface. The minimum detection region in rail track surface is 0.0068 cm2.

Abstract: To the baggage specification automatically detection problem of self-service bag drop system, a baggage size detection algorithm based on stereo vision is proposed. The algorithm is based on binocular stereo vision measurement principle. Firstly, the canny edges of baggage image are extracted as the feature points. With the disparity gradient constraint and epipolar constraint, Stereo matching algorithm based on edge features is proposed, meanwhile, the two images play a symmetric role to ensure the reliability of matching in the matching process. The coordinates of the three dimensional points are derived with approximation of the middle point of the common perpendicular line in different planes. Experimental results show that the proposed algorithm can detect the baggage specification with appropriate accuracy.

Abstract: In view of the drawback of current crane torque monitoring system in real-time performance and anti-jamming performance, a new crane intelligent monitoring device based on ARM and Windows CE operating system is proposed, including its working theory, hardware circuit and software design. Taking the versatility and anti-jamming performance of the system into account, the design and implementation of input signal conditioning modules and output execution modules are elaborated in detail. The application shows that this system is stable and reliable, and can effectively guarantee safe operation of crane, its easy-operation and versatility make it a good application prospect.

Abstract: Abstract. The high-pressure gas test system was developed, which consists of a 0.9 MPa compressor, a nitrogen gas generator, a 15.0MPa compressor, a 35.0MPa gas booster, a gas flowrate device and a sealing pressure test device. “Sensor+PLC+Computer+ Configuration Software” as data acquisition and control model is adopted in the test system. The results prove that the configuration software can combine with PLC (Programmable Logic Controller) to perform many functions such as automatic monitor, respective automatic or manual control, displaying, recording and saving the test data and curves. The monitor and control system is running with perfect stability and reliability.

Abstract: This paper designs a set of electric vehicles online monitoring system with SOA framework, which includes acquisition layer, network layer, support platform, knowledge base layer and presentation layer, and knowledge layer includes a knowledge base management system, reasoning system and man-machine interface system. Also, this paper constructs a knowledge expert system with hybrid rule-based reasoning method of CBR and RBR, finally, electric automobile remote intelligent fault diagnosis is illustrated with the expert systems.

Abstract: In recent years, with the rapid development of electric power, the construction of a large number of substation, electrical measuring instrument and device is also increasing, accordingly, testing and calibration work is growing. The traditional calibration method has been unable to meet the actual needs of work. Combining with the practical work, and put forward a new automatic calibrating method, this paper introduces the electrical measuring instrument verification device of automatic calibration system of the working principle and system structure, and illustrates the system application.

Abstract: Subway fire location has important significance to fire and rescue.This paper analyzes the characteristics of the wireless sensor network positioning technology, using a range-free positioning technology to achieve the positioning of fire, and uses a removable multi-function video platform for the secondary, to achieve the fire video observation and fire location positioning, that makes fire positioning more accurate.

Abstract: Abstract. This paper describes the design of a general purpose multifunction simulator which is used to test radar and its components. The simulator is a hardware system controlled by computer software which generates echoes of targets, clutter and jamming for radar electromagnetic environment scenario simulation. It will responds to the subject radar’s antenna scan by producing composite echoes in real time. Computer programs are used to management the simulation process and allow various combinations of electromagnetic environment. Parallel signal generator is exploited to increase the execution speed and achieve real-time performance. Since the simulator can produce video frequency and intermediate frequency echo separately it can be used for the test of most components of radar. The capability to accommodate dynamic scenarios of long duration in real time for detailed tracking studies distinguishes the simulator from other pulse-by-pulse simulators that have been previously reported.

Abstract: Based on the study of a new method which can calculate the dynamic performance parameters with the dynamic pressure data of the valve in the high-speed on/off process, a test system for the dynamic performance testing of pneumatic solenoid valves is developed in this paper. The dynamic performance of a pneumatic solenoid valve that obtained by test is a key index data for selection and application. To study the dynamic process, a mathematic model of the dynamic pressure in the valve’s control cavity is built up. As analyzing the relationship between the movement of the valve spool and the dynamic pressure during its high-speed on/off process, the method proposed a new criterion that can pick out the key points of the spool’s movement by the data of dynamic pressure which can be obtained by test easily. Then, the dynamic performance parameters of the valve can be determined with those key points. The structure of the test system that formed on this method is presented. Comparing the test results obtained from the new test system build in this paper with the results obtained from the valve spool displacement laser detection system, it is showed that every characteristic parameter is matched well. The comparing error of total opening time delay and total closing time delay are less than 3%. It is verified that the new method can test the dynamic performance of pneumatic high-speed on/off valve accurately.

Abstract: To meet the high real-time performance and high accuracy requirements of signal detection in the rail splicing process, this paper proposes a new type of magnetic grid rail splicing method based on accurately zeroing output signal phase difference of two magnetic grid reading heads, thus establishing two reading heads “shift” rules. The accurate zero setting technology of phase difference is based on Nuttall window algorithm, which doesn’t need to give the exact signal frequency beforehand and sample periodically, and can effectively eliminate phase errors. So this algorithm is suitable for detecting signal phase difference when reading heads go over buff joints with any speed at any initial position. Additionally, simulation test and experimental verification were performed on this detection algorithm and “shift” rules. The results show that, the method mentioned in this paper can real-time detect the phase difference by “shift” rules, when reading heads go over buff joints with any speed or any acceleration.