The development of a layer based machining system
Many useful methods have been applied to Rapid Prototyping (RP) technologies in recent years. Applications of such technologies are restricted because of the limited choice of materials, small part size and low part accuracy. To build large part models with more material choices, a robotic machining system with layer based algorithms is developed. A model represented as a StereoLithography (STL) or StereoLithography Contour (SLC) file is machined layer by layer. The adaptive stock layer thickness is determined based on a visibility pyramid concept. Each stock layer is in turn machined by a number of machining layers. The cutting tool, robotic arms and the rotary fixtures are calibrated automatically by a machine vision system. The effectiveness of the proposed system is demonstrated by the machining of a vase model. Errors of the proposed machining system are analyzed by a Coordinate Measuring Machine (CMM) and a surface texture measuring machine.
rapid prototyping visibility pyramid calibration collision detection