Research On Laser Theodolite Measurement Technique Based On The Guidance Of Optical Axis Of The Camera

The long-term stable development of global economy relies on the design and manufacture of large equipment, which are increasingly high-precision and highly automated with the development of science and technology. Because the manufacture of large equipment is more difficult than conventional equipment, the equipment is usually manufactured in segments and then assembled together. However, the errors induced in each manufacture step will inevitably accumulate, leading to the reduction of large-scale manufacture precision and the failure to meet the practical requirement. Therefore, a high-precision and high-efficiency measurement method will largely improve the precision and efficiency of large equipment manufacture.Theodolite measurement system has high measurement precision and can be set up on-site, enabling its wide application in large-size measurement. However, the traditional theodolite measurement system often requires manual aiming, which causes the poor efficiency and the introduction of artificial aiming errors. It is expected to achieve the automation of theodolite measurement system and eliminate errors due to human factors by the combination of a new kind of theodolite with a servo drive and visual guidance technology. Our group has conducted some research on visual guidance theodolite automatic measurement system. But the existing precise guiding method requires double theodolites move tinily and repeatedly, which reduces the efficiency. In order to solve this problem, we report a novel precise guiding method based on the optical axis of camera. By establishing the relationship between the camera optical axis and theodolite measurement system, we can achieve fast and precise guidance of the theodolite measurement system. This method improves the automatic measurement efficiency at no cost of measurement precision.This paper includes the following aspects:1. The analysis of the background and current situation of large equipment manufacturing and large-size precision measurement technology and the application of large-size coordinate measuring system in manufacturing industry. After that, the research background, significance and main contents are described.2. The measuring principle, directional methods and theoretical optimum measurement area of electronic theodolite system are studied. And the measuring point error is analyzed.3. The visual guidance system theodolite is briefly introduced. And the existing problems are pointed out. Aiming at the problems, we report a novel precise guiding method based on the optical axis of camera. Based on the study of the coordinate transformation theory, the relationship between the camera optical axis and theodolite measurement system is established.4. The principles and methods of the relevant automatic focusing are studied. After that, we design a circuit to archive the automatic focusing function.5. An experimental system is built up, and experiments about the methods reported above are made. At last, a thorough analysis of the errors of the measurement system is carried out.