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Catadioptric panoramic vision system has been widely used in many fields, and also plays a very important role in environment perception of unmanned platform especially. However, the resolution of system is not very high, usually less than 5 million pixels at present. Even if the resolution is high, but the unwrapping and rectification of panoramic video is carried out off-line. Further, the system is also applied in stationary state or low stationary moving. This paper proposes an unwrapping and rectification method based on high-resolution catadioptric panoramic vision system used during non-stationary moving. It can segment dynamic circular mark region accurately and get the coordinates of center of circular image real-timely, shorten the time of image processing, meanwhile the coordinates of center and radius of the circular mark region would be obtained, so the image distortion caused by inaccurate center coordinates can be reduced. During image rectification, after achieving radial distortions parameters (K1, K2, K3), decentering distortions parameters (P1, P2), and the correction factor that has no physical meanings, we can used those for fitting the rectification polynomial, so the panoramic video can be rectified without distortion.

Autonomous off-road navigation is a highly complicated task for a robot or unmanned ground vehicle (UGV) owing to the different kinds of obstacles it could encounter. In-particular, water hazards such as puddles and ponds are very common in outdoor environments and are hard to detect even with ranging devices due to the specular nature of reflection at the air water interface. In recent years, many researches to detect the water bodies have been done. But there still has been very little work on detecting bodies of water that could be navigation hazards, especially at night. In this paper, we used Velodyne HDL-64ES2 3D LIDAR to detect water hazard. The approach first analyzes the data format and transformation of 3D LIDAR, and then writes the data acquisition and visualizations algorithm, integrated data based on ICP algorithm. Finally according the intensity distribution identifies the water hazard. Experiments are carried out on the experimental car in campus, and results show the promising performance.

Structured light extraction is an important problem in 3-D measurement of structured light. Due to traditional structured light extraction methods are mostly applied in small visual field and simple environment. Therefore, a novel method is proposed based on the feature of structured light aiming at the large field and complex surroundings. Firstly, a region of interest (ROI) is obtained through a third sensor in order to reduce calculations and process conveniently. And then, structured light is extracted according to its feature of brightness distribution module and geometrical morphology trait. Experiment shows that this new method not only extracts structured light in such large field with strong background noise well but also reduces the computation to meet real-time requirement.

Optical flow method is an important and valid method in the field of detection and tracking of moving objects for robot inspection system. Due to the traditional Horn-Schunck optical flow method and Lucas-Kanade optical flow method cannot meet the demands of real-time and accuracy simultaneously, an improved optical flow method based on Gaussian image pyramid is proposed. The layered structure of the images can be obtained by desampling of the original sequential images so that the motion with the high speed can be changed into continuous motion with lower speed. Then the optical flows of corner points of the lowest layer will be calculated by the LK method and be delivered to the upper layer and so on. Thus the estimated optical flow vectors of the original sequential images will be obtained. In this way, the requirement of accuracy and real time could be met for robotic moving obstacle recognition.

Effect of welding heat input on the microstructure of the automatic ultra-narrow gap welded NK-HITEN610U2 steel heat affected zone (HAZ) was studied. Five heat input combinations (6kj/cm, 10kj/cm, 14kj/cm, 18kj/cm, 22kj/cm) were designated for the research. The weld joints made using these five combinations were subjected to micro-structural evaluations and hardness test for analyze the effect of the heat input on the microstructure. The results indicated that the width of heat affected zone increased with increase in the heat input.

Strain measurement in electromagnetic rail launching processes is of significant importance to studies on rail life, wrap material selection, and initial armature disturbance. Based on a discussion about the principle of fiber-optic differential strain measurement, the constitution of a rail strain measurement device based on fiber-optic differential interference was introduced, and its data processing method and system calibration method were discussed. With this measurement method, electromagnetic rail strain measurement was completed, and experimental results indicate that the differential strain measurement device is able to operate reliably and stably under an intense electromagnetic interference environment in an electromagnetic railgun launching process and can be applied to strain measurement and in-bore projectile motion velocity measurement of gun barrel weapons.

With the mining depth increasing, the effect of temperature on coal mine is outstanding with each passing day. In order to enhance the tunnel insulating layer heat insulation effect, thermal insulation glazed hollow bead concrete will be used in tunnel wall thermal insulation layer, the characteristics of thermal insulation glazed hollow bead concrete will be discussed and the appropriate mixture ratio and coefficient of heat conductivity will also be determined, as well as in the basis of reasonable theoretical analysis and derivation, prediction of the thermal insulation material of surrounding rock after exhaust heat will drop significantly, and it is proved that the thermal insulation glazed hollow bead concrete used in deep mine roadway can produce the benefit and have broad prospects.

Based on the designed, packaged high-g acceleration sensor in measuring demonstrated sensor performance between individuals have big difference, Researched this problem, through the analysis that the main reason of this problem appeared in the sensor package process of Die process. Through ANSYS simulation and experimental test on two aspects of the analysis the die adhesive’s amount of Die process is the high-g acceleration sensor in testing large performance differences were the main factors. Packaged high-g acceleration sensors with die process of quantitative die adhesive were designed and tested their performance. The result showed that, the simulation results were consistent with experimental results.

The Mg-12Gd-2Y-0.5Sm-0.5Sb-0.5Zr (wt.%) alloy was prepared by casting technology. The microstructure of alloy was then investigated after T6 heat treatment. The results show that at 523K, the alloy has shown the superior tensile strength (i.e. 345.5 MPa). When experimental alloy was stretched with temperature increasing from 293K to 523K, the increases of deformation strengthening and critical crack propagation stress caused the anomalous temperature dependence of tensile strength.

The emergency of wireless sensor network provides a distributed, low cost and flexible solution for acoustic localization system. Location precision is a critical parameter for this system. In this paper, we use True Time, which is a Matlab/Simulink co-simulation block library to establish a simulation environment and establish a relationship between localization precision and PRR (Package Reception Rate). With the PRR decreasing, the AOA precision is get lager. Hence, in a given spatially deployed sensor network location system, the location precision will get larger. Therefore, the PRR should be controlled in a rational level, which is depended on the trade-off between performance and efficiency.