Force and position deviations estimation for ultra-thin tube assembly

Abstract

Purpose Micro ultra-thin tubes have important implications in aerospace, nuclear energy and other fields. In microassembly process, these parts are characterized by following reasons: the small size can easily lead to damage when gripping, even for low intensity and the parts are mainly affected by the instability of light source, for vision-based systems, the visual information about ultra-thin tubes is difficult to gather and the contact state is hard to monitor. Design/methodology/approach The paper presents a new method to adjust the position deviations based on contact forces during microassembly processes. Specific research is such that the assembly model was established based both on mechanic calculation and numerical simulation; the assembly task was carried out on an in-house microassembly system with coaxial alignment function (MSCA), the contact statements were controlled based on force sensor feedback signals and the model of the relationship between contact force and assembly deviations was established. Through a comparative study, the results of experiment and simulation differ by less than 11 per cent, validating the accuracy and feasibility of the method. Findings The model of assembly force and position deviations of micro ultra-thin tubes based on MSCA has been built. Besides, the assembly force threshold, and the assembly process parameters have been obtained. Originality/value The assembly process parameters obtained from experiments can be applied in the precision assembly and provide theoretical guidance and technical support to the precision assembly of the multi-scale parts.