Tool path optimization in layered manufacturing

Abstract

There are several manufacturing applications in which a tool needs to move along a prescribed path performing machining operations. The path is typically described by a sequence of curves. For the entire process, the tool must move along each curve exactly once. For typical paths, significant time may be wasted in the movement between the end point of one curve to the start vertex of the next one along which the tool must operate. Normally, this non-machining motion is a straight-line motion. A good process plan would minimize the time wasted on such motion. An excellent application of this problem is found in the increasingly popular Layered Manufacturing (LM) methods. We first introduce a Genetic Algorithm (GA)-based approach to solve this problem. Next, we present a new strategy using a combination of the Asymmetric Traveling Salesman Problem and Integer Programming (TSP-IP) to solve it. Based on the pros and cons of these approaches, two enhanced GA formulations are developed. We compare the performance of the different techniques, with a view to their application to real-time path planning in LM applications.