Error Analysis of a Kind of Binocular Visual Alignment Device

Precision assemblies of small interference fitting parts are usually achieved by precision press-fit instrument. As the key module of the precision assembly system, the alignment accuracy of the visual alignment device (VAD) directly affects the assembly quality. In this paper, a precision press-fit instrument was introduced, in which contain a kind of binocular visual alignment device. For this kind of VAD is combined with two cameras and a three-dimensional precision displacement platform, a calibration method was introduced in this paper to measure the tilt angle of the guide rail Z, and the error caused by the tilt of the three guide rails of VAD was analyzed. Finally, the final transfer equation between this two cameras was obtained by taking the error into account. The experimental results show that the analytical method can help the press-fit instrument improve the alignment accuracy effectively, and the alignment accuracy can reach ±10μm, so the instrument can meet the requirement of the assembly work.