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Remote control excavator solves the personal safety problem of operators in dangerous conditions, but the video surveillance of remote control excavators can't sense the stereo distance of the target. To solve the problem, the binocular vision method is used to reconstruct the 3D operating scene of the excavator, and help the drivers to effectively sense the spatial position of the target and bucket to improve the efficiency of remote control operation. Firstly, the noise generated by binocular camera during data collection was removed by guided filtering. And then, left and right images were matched by features based on Sum of Absolute Differences (SAD). Then, the generated disparity value was optimized according to the Winner Takes All(WTA) strategy. Finally, the disparity map of the working scene was obtained and the 3D reconstruction of the scene was completed. The experimental results show that the binocular 3D reconstruction system used in this paper can realize the 3D reconstruction of different scenes indoors and outdoors through the cooperation of software and hardware.

For the problem that the contact sensors measure position is not reliable, a method of identifying pose information of excavator working device by non-contact visual camera is studied. First, the camera takes a two-dimensional map of the excavator's working device, which is subjected to image processing to obtain a binarized image. Then, the image is extracted and the pixel coordinates of the joint of the working device are obtained, and the accuracy of the different algorithms is compared. Finally, the transformation matrix between coordinate systems is deduced by theoretical calculation, and the coordinates of the pixel are converted into world coordinates with OpenCV software, and the correctness is verified by experiments. Experimental results show that: the error between measurement results obtained with this method and Total Station is within 30mm and the two are in good agreement. They can be applied to the actual measurement of excavator's position and orientation.

During the service, cracks may occur in the steel structures of the crane. The capacity and service life of the cracked structures can be improved by bonding composite patches to the cracked areas. In order to better formulate the adhesive repairing scheme of cracked structures, the finite element models of the cracked steel plates bonded with composite patches were established with ABAQUS. The effects of patch length, stiffness, steel plate thickness and adhesive layer shear stiffness on the stress intensity factor (SIF) at the crack tip and the adhesive layer stress of the repaired structure were analyzed. The results show that selecting reasonable patch parameters and adhesive layer shear stiffness can not only effectively reduce the stress intensity factor (SIF) at the crack tip, but also improve the stress state of the adhesive layer. The bonding technique has a poor repairing effect on cracked steel plates with a large thickness. The conclusions can provide references for the development of repairing scheme for cracked steel structures.

This report describes the preparation of undoped, polyethylene glycol (PEG-400)-added, Fe-doped, Pd-doped and Fe-, Pd-doped, PEG-400-added SnO2 thin films using sol–gel technology. The gas-sensing properties of the five abovementioned structures were investigated over a range of 50–2000 ppm H2. The linear response magnitude (S) response profile of Fe-, Pd-doped, PEG-400-added SnO2 thin film toward H2 concentration (C) was observed, and a concise formula without any transformation was expressed as S = 1.724 + 0.046 C (correlation coefficient (R) = 0.99803, probability (P)