A 3D Curve Offset Approach for Ruled Surface Generation in Engineering Design

TL;DR

This paper introduces a novel 3D curve offsetting algorithm that addresses common issues like breakage and overlap, improving the quality and efficiency of ruled surface generation in engineering design.

Contribution

It presents new methods for curve division, overlap detection, and a spherical rational Bezier curve transition to enhance 3D offsetting accuracy and surface quality.

Findings

Improved offset accuracy with reduced errors.

Effective detection and elimination of overlapping regions.

Enhanced smoothness of generated ruled surfaces.

Abstract

Ruled surface is widely used in engineering design such as parting surface design of injection mold and checking surface design of checking fixture, which are usually generated by offsetting 3D curves. However, in 3D curve offset, there often exist break,interaction and overlapping problems which can't be solved by current CAD software automatically. This paper is targeted at developing a 3D curve offsetting algorithm for ruled surface generation, and three key technologies are introduced in details: An improved curve division method is proposed to reduce the offset accuracy error resulted from different offset distances and curvatures; An offsetting curve overlapping detection and elimination method is proposed; And then, a curve transition method is presented to improve curve offsetting quality for the break and intersection/overlapping regions, where a new algorithm for generating positive weights spherical rational quartic Bezier curve is proposed to bridge the breaks of offset curves to create a smooth ruled surface. Finally, two practical design cases, parting surface and checking surface generation, show that the proposed approach can enhance the efficiency and quality for ruled surface generation in engineering design.