Precision manufacturing of components often requires finishing operations to remove burrs. In many cases, the deburring processes are not automated and are dependent on manual operations, and they become the bottleneck in automated production systems. As a result, the automation of the deburring process has become an important objective as a part of efforts to automate the entire production line. Moreover, progress in manufacturing has resulted in the need for improved deburring technology which can provide enhanced part quality and flexibility to manufacturing automation.; This thesis is focused on the development of an effective way of automated deburring of precision components. A high power laser is proposed as a deburring tool for complex part edges and burrs. Also, an overall deburring automation strategy with descriptions of the essential elements--a deburring technology, a sensor feedback for the process control, a burr measurement/characterization scheme and the burr formation modeling of a blanking operation--is presented.; For the laser deburring process, the finite element method was used to predict the cutting profile of laser-deburred parts and the HAZ (heat affected zone) near the cutting area, the results of which show good agreement with experimental data. It is shown that, if combined with an effective process control strategy and appropriate sensing techniques, laser deburring could be a viable approach for automated precision deburring.; For the sensor feedback for process control of the laser deburring, an acoustic emission (AE) technique was introduced. The implementation of AE, which has been developed as a feedback sensing technique for precision (mechanical) deburring, in precision laser deburring process is presented. The results, such as the sensitivity of AE signals for different laser cutting depths, edge detection capability and the frequency analysis show a clear correlation between physical process parameters and the AE signals. A subsequent control strategy for deburring automation is also discussed.; An "on-line" burr measurement scheme using a capacitance sensor is described. A non-contact capacitance gauging sensor is attached to an ultra precision milling machine which was used as a positioning system. The setup is used to measure burr profiles along machined workpiece edges. Experimental procedures and results as well as the basic theoretical principles of the capacitance sensor and specifications of related equipment are presented. The proposed scheme is shown to be accurate, easy to setup and, with minor modifications, readily applicable to automatic deburring processes.; Last but not least, a burr formation model for precision blanking operation, which is a typical burr forming operation in precision parts, is presented. The finite element method was used to describe the burr formation as well as the shearing mechanism in blanking operations. The FEM results show good agreement with the experimental results in predicting the shearing force and the cutting geometry. With this burr formation model, burrs can be eliminated or minimized in the machining stage, or the burr data can be used as input in the deburring automation system.
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