Summary: | 碩士 === 國立成功大學 === 機械工程學系碩博士班 === 91 === Choosing machine configuration and tool geometry are frequently encountered problems during multi-axis surface machining. Traditional solutions to these problems depend on the expertise and experience of engineers, which are error prone on selecting machine configuration and tool geometry. If a preliminary analysis system is available before manufacturing process is committed, the errors caused by lack of experience can be avoided in advance.
In this research, visibility cone theory and feasible tool orientation are combined to perform the configuration analysis. Feasible tool orientations for each configuration are obtained by coordinate code of the machine tool and coordinate transform matrix. The feasible orientations are then compared with the surface geometry to obtain feasible setup orientation. For three-axis and four-axis machining, the first priority of setup orientation is to finish the machining without secondary setup orientation. When secondary setup orientation is inevitable, a proper indexing angle is automatically generated by the system for 3.5-axis and 4.5-axis machining. For five-axis machining, visibility cones of the workpiece are combined to find the minimal necessary angle for the rotary axis of the specific machine tool.
In conventional visibility and visibility cone analysis the tool geometry and its effect on the manufacturability are often ignored and only a vector with infinite length is considered. In this research, geometric parameters of ball end mill and flat end mill cutters are considered in the visibility cone analysis. The maximum interference free tool geometry is provided for the upper bound when selecting tool geometry.
In this research, a manufacturability preliminary analysis system based on machine tool configuration and constrained tool geometry is proposed to avoid collision and interference problems during the process planning of surface machining. The proposed system can be used for machine tool selection and tool size selection for surface machining and is capable of reducing machining cost and time-to-market.
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