Numerical Implementation of Drop Spin and Tilt Method For Five-Axis Tool Positioning For Tensor Product Surfaces

This paper presents an extension of multi point machining technique, called the Drop Spin and Tilt (DST) method, that spins the tool on two axes, allowing for the generation of multiple contact points at varying distances around the first point of contact. The multiple DST second points of contact were used to manually generate a toolpath with uniform spacing between the two points of contact. The original DST method used a symbolic algebra package to position the tool on a bi-quadratic surface; our extension is a numer- ical solution that allows positioning a toroidal tool on a tensor product Bezier surface. Further, we investigate the spread of possible second points of contact as the tool is spun around these two axes, demonstrating the feasability of using the method to control the machining strip width.

Effective Determination of Feed Direction and Tool Orientation in Five-Axis Flat-End Milling

This paper addresses the challenging problem of determining feed direction and tool orientation at a given cutter contact (CC) point in five-axis free-form surface machining with flat-end mills. The objective is to efficiently determine a feed direction and tool orientation that will avoid both local and global tool gouging and yield a near maximum machining strip width at the CC point. Concurrent determination of the optimal feed direction and tool orientation is a very computationally intensive task and searching for the correct solution would involve exhaustive evaluations of the machining strip width at many feed directions and tool orientations. In this paper, the optimal feed directions and analytical solutions for the optimal tool orientations in five-axis flat-end milling of spherical, cylindrical, and toroidal surfaces are identified first. A toroidal surface inscription method is devised to approximate the local surface geometry at a CC point on a free-form surface by an inscribed toroidal surface. Analytical solutions for toroidal surface machining are then employed to position the flat-end mill at the CC point with the tool feeding in the best toroidal surface inscribing direction. Case studies have demonstrated that the proposed method can efficiently determine a feed direction and tool orientation, corresponding to a near maximum machining strip width.

Flank Milling for Blisk with a Barrel Ball Milling Cutter

To satisfy the requirement in blisk machining, a barrel-ball milling (BBM) cutter suitable for machining both blade and hub is presented in this paper. The selection of cutter parameter and calculation of cutter location were put forward. The new efficient machining cutter location via the advanced optimization on cutter machining strip width was gained. By the numerical simulation of blisk blade machining, the feasibility of the BBM cutter and cutter location strategy were verified. The result showed that the efficiency of this method was increased to more than three times compared to the machining with a ball cutter.