A Laser Based Building Subsidence Image Monitoring System

In the design,construction,acceptance and use of constructional projects,it is necessary to monitor the various state of the project for a long time,in which the monitoring of building subsidence is very important.Regular monitoring of the settlement of engineering buildings,understanding of their deformation,detection of anomalies and timely remedial measures are important to building structural safety and life safety of people's property.With the continuous improvement of the requirements for the settlement of construction projects in the country,the present conventional methods of settlement measurement are complicated,time-consuming and laborious,expensive and low in measurement precision,so it is urgent to research and develop high precision and high-efficiency real-time monitoring equipment for automatic building subsidence,and it has great application value.In this paper,firstly,based on the survey principle,technical specification of building subsidence engineering and the research on the current situation and development trend of building subsidence monitoring in China and abroad,combining photoelectric detection technology with digital image processing technology,a building subsidence monitoring model is presented,According to the structure of the construction subsidence monitoring system,the imaging system based on two-line CCD optical stitching is designed,the stitching error and stitching image processing method are analyzed,and the multi-point settlement monitoring network scheme is studied theoretically,and the error compensation method is put forward for the problem of multiple monitoring points error accumulation,Furthermore,a real-time prediction method of building subsidence and construction risk assessment mechanism for multiple monitoring points are proposed.Secondly,the hardware scheme of the settlement monitoring system based on CPLD+DSP is designed for the data acquisition and image processing technology,the driving logic control of the system is realized by CPLD,the image processing and data are solved by DSP,and the hardware feasibility is verified by software simulation and waveform analysis.Then,the algorithm of spot image processing on the dualline array CCD is studied,the model and algorithm that can detect spot image in real time and accurately are studied,and an algorithm of uneven distribution of light energy of CCD splicing based on the improvement of spot center location error is proposed to ensure the high precision measurement of spot subdivision in the system.Finally,the simulation experiment platform of building settlement monitoring system and the upper machine interface are designed,the rationality and validity are verified by building settlement simulation experiment.Eventually,the main error causes and elimination methods of the system are analyzed by combining the experimental results with the actual situation.The purpose of this research is to develop a building subsidence monitoring system which can monitor multiple monitoring points,a large number of process and high precision monitoring in complex environment.The experiment shows that this system can realize the high precision real-time monitoring of building subsidence,and the measurement precision is high,which can meet the requirement of practical engineering application.