An Improved Tolerance Modeling Method Based on Bézier Parametric Space Envelope

doi:10.3901/JME.2021.09.183

Abstract

Abstract: Geometric tolerance is modeled indirectly through Bézier curve constructed space envelope. Under the new approach, tolerance zone is transformed and converted into control points’ influence zone. For worst case tolerance modelling, this paper applies the concept of hyper-ellipsoid to solve control points’ influence zone. This compares favorably with tangent hypersphere method measured by increased control point influence zone for a given geometric tolerance. This is achieved by better capturing the feasible region of the system of nonlinear equations. Similarly, the proposed method also improves the statistical tolerance modelling. The advantage of the proposed method is verified through an industrial case study. As geometric tolerance is closely linked to manufacturing costs, the improvement offered by this paper will have significance in industries in terms of reducing manufacturing costs in real production.

Key words: geometric tolerance, parametric space envelope, free-form deformation

CLC Number:

TH124

LUO Chen, NIE Jiaqi, ZHOU Yijun. An Improved Tolerance Modeling Method Based on Bézier Parametric Space Envelope[J]. Journal of Mechanical Engineering, 2021, 57(9): 183-190.

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