| As the counterpart mechanism of serial robot, parallel robot has merits such as high mechanical stiffness, high precision and no accumulation of position errors etc, and has become a hot research topic in domain of robot. At present, parallel robot has found its wide and important applications in such areas as aviation, astronautics, submarine engineering, manufacturing, computer aided medical equipment and mirco eletro-mechanical system(MEMS) etc. Nevertheless, there still exist some challenging problems in mechanics, kinematics, dynamics, motion control, path planning and practical applications of parallel robot in spite that a large amount of achievements have been obtained in theory investigation and practical application. Supported by natural science fund of Hebei province, parallel robot will be applied into area of engraving Chinese characters in this dissertation to fully exert its merits and extend its application area. To make parallel robot engrave Chinese characters successfully, the author implements deep research on related theory and technology such as image processing of Chinese characters, planning and generating of tool path for engraving, analysis of kinematics and dynamics, calculation and control of engraving force etc. A general method for transforming image information of Chinese characters into engraving tool path information of parallel robot is studied. It mainly includes the following contents:algorithms for image preprocessing of Chinese characters such as normalization and contour extraction etc; an improved thinning algorithm of Chinese characters' image based on template matching and a novel stroke extraction algorithm based on distance; protruding and concave tool path generating algorithm for engraving on plane; tool path mapping algorithm from plane to sphere and other complicated curved surface; real-time planning method of cutting tool's guise etc. Chinese characters engraving system based on parallel robot, including both hardware and software, is organized and developed also. Kinematics and dynamics of parallel engraving robot are studied. The first and the second order influence coefficient matrices are computed, and mechanical performances for kinematics and dynamics such as angular velocity, linear velocity, angular acceleration, linear acceleration, force and moment, inert force are analysed based on its influence coefficient matrices. So the mechanism size with better performance for every index can be selected according to the performance atlas. A general forward displacement solution for parallel robot based on self-configuration quick BP neural network is presented, and analysis result for the engraving robot is given. The rigid body dynamics model of engraving robot is established based on Newton-Euler method, and dynamics experiment is also analysed with this model. Engraving force and its control technology is studied, the factors influence on engraving force are analysed, and calculating method of engraving force is given. Especially, the influence of different fonts such as Song, Hei, Lishu and Kai on engraving force is studied. The control method of engraving force based on fuzzy neural network is proposed, and its difference between traditional impedance is also discussed, experiment results verify the validity and feasibility of proposed method. The overall system scheme of remote Chinese characters' engraving for parallel robot based on B/S mode is designed. The several technologies such as video information real-time transmission, submission and analysis of remote engraving information and task control etc are deeply studied and realized.
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