An evaluation for tube assembly performance based on virtual fixtures

There are a lot of complex tubing in aviation, aerospace, automobile, and other industrial machinery and equipment. The reliable assembly of these tubing directly affects the quality of the products. Tube has two targets in assembly including assembly performance and avoiding obstacles. Thus, the assembly results is an overall merit based on the geometry error. It is easy to get geometry error of a tube, but the problem is how to evaluate the assembly result according to the geometric errors. The current approaches have a good performance in analysis of idealized assembly. However bend tubes have complex topology and shape, current solvers cannot account for the natural manufacturing and assembly variability that occurs in assembly of bend tubes. In order to make accurate predictions about assembly performance and product quality, the variability of the assembled tubes must be evaluated in the assembly model. This article outlines two key targets in tube assembly based on the function of bend tube. To achieve the assembly targets, a method based on virtual fixture is proposed to evaluate the bend tube assembly performance. The evaluated bend tubes are adapted by the virtual fixtures and reach to an exact position to evaluate the assembly performance. Numerical experiments with Monte Carlo method are designed to simulate the method, analyze the results, and prove its feasibility. Designers and manufacturing engineers can efficiently evaluate the assembly performance or judge the assembly ability of a produced tube from its geometric errors.