Feature-based robot machining for rapid prototyping

Abstract

This paper presents the development of a robot machining centre for rapid prototyping (RP) applications. Given a three-dimensional model of an object, surface features of the model were extracted and analysed. Cutter paths for both rough and finish cutting were then generated on the basis of the extracted surface features. In order to detect collision between the robot arm and its environment, an accurate model was built using a computer aided design (CAD) system and the Denavit-Hartenberg (D-H) notation was used to represent the robot arm transformation matrix. When collision was detected for a given contact point, both cutter location and robot arm positions were modified. A simple ship model was machined to demonstrate the effectiveness of the robot machining centre. Finally machining errors were quantified with the use of a coordinate measuring machine (CMM).