万向支架微小螺纹副自动装配系统

针对万向支架微小螺纹副装配自动化程度低、一致性差的问题,研制了一套自动装配系统,并对装配过程中的微小螺纹零件中心位置提取方法和多个微小螺纹副之间的装调策略进行了研究.首先,提出了一种改进的清晰度评价函数,并基于该函数实现了机器视觉装置的自动聚焦.然后,针对螺轴以及内环螺纹孔的端面特征不对称问题,提出了变聚焦位置分区域图...

Miniature Thread Pairs Automatic Assembly System for Gimbals

An automatic assembly system was developed aiming at solving the problems of weak automation and poor assembly consistency of miniature thread pairs during gimbal assembly. The extraction method of the central positions for the threaded parts and the tightening strategy of multiple miniature thread pairs were studied. Firstly， an improved clarity evaluating function was proposed， and the auto focus of machine vision device was realized based on the evaluating function. Then， aiming at the asymmetry of the end surface features of the threaded shafts and the threaded holes of the inner frame， the variable focused and regional image acquisition method was proposed for extracting the center of the inner and outer threaded parts. Finally， combining the relationship between the input rotation angle and the axial displacement of the inner and outer frames in the loading and unloading processes， the tightening strategy called cross unloading-loading in group was proposed for multiple threaded joints. The system prototype for assembly experiments was built， and the experiments were carried out. The results show that the coaxiality between outer frame and base frame is less than 5 μm， the axial displacements of the inner frame and the outer frame are less than 3 μm， which may meet the coaxiality requirements of the gimbal.