In recent years, the research of micro-assembly technology and system have been widespread concerned, because of being able to achieve high precision assembly operations. Micro-assembly robot in the guided of microscope vision provides an effective solution for the three-demensional space assembly of small parts. This topic is dedicated to study the micron grade precision automatic micro-assembly system. On the platform consisting of three vision systems and six manipulators, we study on the micro-vision image processing and feature extraction and recognition methods, and the image Jacobian matrix calibration method between the nonorthogonal visual system and multiple robot manipulators. We have designed the hybrid control strategy of micro-viosn and micro- tactile. Finally multiple micro-assembly operations reach high precision. The main work is described as follows. (1) For the edge characteristics of cylindrical micro-parts, we have compared the focusing evaluation function of time-domain and airspace and statistic methods. In this paper, a coarse-fine autofocus algorithm for tracking micro-parts features has been proposed. Improve focus searching algorithm, employ mean filtering for the focusing evaluation function, and eliminate local extremum points can effectively prevent the focus getting into local maximum value which leads to focusing failure. (2) For the circular feature detection, we have compared the classical least squares fitting circle method and the circle Hough transform detection method. Finally we proposed a highly real-time and strong anti-jamming and highly accurate method using the circular string midperpendicular to fitting the cicle. (3) The image Jacobian matrix calibration method for multiple micro-vison system has been proposed. The image jacobian matrix can be obtained by active movements and the least square method. This calibration method can solve the mapping problem between nonorthogonal visual systems and multiple manipulators in any position. We have designed the PI controller to achieve the visual servoing control of micron grade accuracy for multiple micro-parts three dimension posion and posture alignment. (4) In order to realize the long distance and undamaged interference fit inserting of two micro components, we have proposed hybrid control method based on microscopic visual systems and micro force sensors. Visual servo control is adopted to accomplish posion and posture alignment between the micro-parts, force fe...
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