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It is proposed a computational model of spatial formation of cracks in reinforced concrete constructions under the action of torsion with bending, based on working assumptions and constructed equations. The physical interpretation of the solution is that it allows to search for generalized minimum load, which corresponds to the formation of the first crack and the spatial coordinates of the point of its formation.

In this paper, the main design parameters of 750 kw horizontal-axis wind turbine wheel are computed based on simplified theoretical design model; The airfoil coordinates of the blade derived from Profili are spatial switched in Excel, then the spatial coordinates of every foline are obtained; In SolidWorks, the curves of foline outlines are drawn on the basis of former coordinates. Eventually, the 3D model of the blade is created by loft surfacing according to the foline outlines. The blade model created in this paper could be used in the coming finite element analysis.

Precise measurement of tooth profile errors is the key technology for realizing close-loop manufacturing of spiral bevel gears. The measuring principle of tooth profile errors and the processing method of measuring datum is the key technology for realizing precise measuring. Based on the generating principle of spiral bevel gears and the model of CNC machine tool, the on-machine measuring principle and the measuring datum processing method were established. In order to verify the correctness of on-machine measuring principle, the on-machine measuring simulation system was established based on AutoCAD development platform. According to the spatial coordinates and normal vector of the discrete points of theoretical tooth profile, the on-machine measurement of tooth profile errors was simulated by intersection Boolean operation and the values of errors were calculated. The correctness of simulation algorithm is validated by comparing simulation result with the practical measuring result.

The research programs and positioning methods of precise positioning technology of the Mine locomotive unmanned systems were discussed in this paper, It implements the positioning of three-dimensional spatial coordinates, and analyses the experiment of positioning calculation and positioning deviation. Experimental results show that the new technique and method can improve precision positioning accuracy above 5%, and provide reliable security protection for the Mine locomotive unmanned systems.

Resolving the contradiction between trees and power transmission lines in time is an important work to ensure the safety of transmission line operation. While it is difficult to decide the trees trimmed time during the transmission line operation and maintenance, the development of the management information system for protecting distance between transmission lines and trees, which is used to auxiliary predict the date of pruning, is a way to solve the problem. Collected attribute data of transmission lines and trees, the corresponding database is established. Therefore, Visual Basic 6.0 is adopted to develop the software system. Based on the spatial coordinates of line towers, conductors, and tree crown, the three-dimensional mathematical model is established to calculate the spatial distance between the conductor and tree crown. According to the mathematical model, the trees growth rate of year, month and day, respectively, and the protecting distance standard between conductor and tree crown, the system could calculate the actual spatial distance between conductor and tree crown, and auxiliary predict the pruning date.

A new calibration method for camera interior orientation parameters is proposed using the known spatial coordinates and the corresponding single photo. Firstly, principle point coordinates, principle distance and exterior orientation parameters are solved by the direct linear method without consideration of distortion parameters. Then, accurate interior and exterior orientation parameters are refined through the process of nonlinear optimization, during which the distance of spatial point to corresponding ray are minimized. Distortion factors of radial distortion, tangential distortion, affine distortion and non-orthogonal distortion are taken into consideration. This paper uses Levenberg-Marquardt optimization method to avoid inaccurate initial parameters influence upon the process of convergence.

Tracking of human body motion is applied in many fields, such as virtual reality, clinical biomechanics, the study of man-machine-environment relationship, the analysis of sports movements, etc. Nowadays, the preferred approach to tracking human body motion is based on the use of appropriate optical or magnetic markers, which are placed on specific landmark points, and real-time estimating of their spatial coordinates. With the improvements introduced in computerized monitoring of human motion kinematics, it is important to emphasize the significance of combining motion capture data with commercial CAD packages. The aim of this research was to develop new interactive methods in creating virtual models within the highly sophisticated CAD computer technologies, as well as computer simulations for analyzing the various forms of human locomotion. Within this research, special attention is focused on the study of locomotion when climbing stairs, as an activity that requires large amount of metabolic energy, and thus represents great difficulty in performing daily activities for people with disorders of the musculoskeletal system, and particularly for people with lower limb amputation.