Research On Large Aircraft Component Assembly Based On Laser Ranging Technology And Machine Vision

The measurement aided assembly technology is an important part of the aircraft digital assembly technology.In the measurement aided assembly technology,the high precision measurement auxiliary technology is the guarantee of the high quality of the aircraft docking assembly.Large-scale measuring equipment(such as laser tracker,iGPS,etc.)is susceptible to temperature,airflow and other non-stability factors,and is difficult to apply to large aircraft component assembly in an external field environment.This paper proposes a method of large aircraft component assembly using laser ranging technology and machine vision.The main research contents are as follows:1)This paper proposes a new method of large components assembly based on laser ranging,and the error factors are comprehensively analyzed.a method based on Laser Range Sensing is proposed.Firstly,the basic composition and principle of the system based on ranging are introduced.The current pose of the component is solved via the singular value decomposition(SVD)method,and the model of the large-component docking target pose based on laser ranging is constructed with the geometry analysis method and the small rotation model.Then,according to the kinematics of the attitude platform,the amount of posture adjustment of each positioner is calculated.As the error exists in the adopted method and system,Monte Carlo simulation method is used to analyze the ipmact and law of the main error source on the accuracy of the attitude adjustment.2)The method of measuring the displacement of the intersection hole based on machine vision is studied.The ellipse detection fitting algorithm is summarized.The method of solving the spatial intersection hole pose based on monocular vision is given.The calculation method is used to calculate the size of the connecting pin that can be inserted into the intersection hole in the case of parallel axis,axis intersection and axis misalignment.3)The test platform was built and the corresponding application was developed.The positioning accuracy test based on laser ranging guide docking,the machine vision based intersection point pose measurement accuracy test and connection pin size calculation method verification test were carried out.