A Study Of Precise Inspection Technology For Dynamic Surveying Precision

As a newly emerged technology, dynamic surveying technology is applied to more and more surveying cases, leading to great changes for traditional surveying in terms of both working efficiency and the technology connotation. Dynamic surveying is different from the static surveying in terms of precision evaluation and the methods of data processing. And with the increasingly wide application of dynamic surveying error, it is really necessary to carry out the research into it. The purpose of the essay is to establish an effective inspection plat for dynamic surveying which can be applied in the practice of dynamic precision inspection.The feasibility of inspection platform and the principal are addressed based on the analysis of some optic-mechanical -electric instruments and the appliances, and the optimal proposal is made after the comparison between several potential solutions. Based on the principal of inspection, the 20cm and 60 cm reduce-scale models are designed and the model composition are also depicted, with which some relevant instruments are tested. Then the 100cm model is successfully completed on the basis of the reduce-scale models. In order to achieve precision, the time system, photoelectric sensor, servo motor and mechanical apparatus are tested according to the composition of the inspection system. Different precision for inspection system in different plans are figured out according to the results of all the factors: under low velocity condition(lower than 3cm/s), the precision for total station is from 0.4mm to 0.6mm, while the absolute and relative precisions for GPS dynamic surveying are 3mm -10mm and 0.5mm under low and median velocity condition(lower than 6m/s). the experiments and analysis for the dynamic precision of total station and GPS are carried out based on 100cm model, and the results of preliminary dynamic surveying and real-time dynamic surveying are gained through post-processing. Meanwhile, through the correlation analysis for surveying errors, the surveying delay ranges from 110ms to 124ms under different dynamic conditions. After the correction of surveying time-delay and the cooperated-target 360 degree prism, the errors are dramatically reduced: the vertical error and horizontal error are reduced from 1.02mm and 2.18mm to 0.83mm and 0.51mm respectively under the velocity of 0.9cm/s, which proves the effectiveness of error correction. There is little difference in the static and dynamic errors (lower than 0.314m/s), as for vertical and horizontal results under the condition of GPS dynamic differential surveying, in which the horizontal standard deviation is lower than 5cm while the vertical standard deviation approches 1cm. The experiments of different double-moved GPS dynamic surveying prove a systematic error of 2-3cm and standard deviation of 7-8cm. All the results prove the platform's effectiveness and qualification for inspection.