Research Of Line-structure Light In The Experimental Landform Survey

The measurement of the topography parameters is important in the physical model experiments. The high-performance techniques can improve the accuracy of the simulation results a lot. Firstly, this paper reviewed the results of previous researchers at topographic survey technical, proposed a method of line-structure light in experimental landform survey and designed the landform survey instrument based on the technology principle. Secondly, the article analyzed the measurement system error and discussed the process of the image dates. Finally, the landform survey technology based on line-structure light was used to measure the physical river model, and then analyzed the performance of the landform survey instrument by compared with traditional methods. The main research results are as fallows:(1) Work has been done to design the W and G Landform survey instrument based on the linear structured light vision measuring technology. The former is suitable for physical river model measurements with high precision and fine surface modeling. And the precision of the new technology is remarkable in static target terrain measurement and high observation efficiency. The G topographic meter is particularly suitable for observing the slope-gully erosion topography in real time, and can be easily calculate the erosion volume. Both of them can acquire the data quickly and accurately, and then be used to form the terrain isoline value maps, establish 3D surface model, and terrain 3D calculation.(2) The method of multi-line structured light is a non-contact survey method with high precision and efficiency, and has a good practicability on the survey in the 3D physical river model. Compared to the method of survey probe, the method of multi-line structured light would perform better on surveying and simulating the landform. From the analysis of linear regression and statistics, the measurement error of W topography meter was evaluated based on the section point value of the elevation and plane on the 3D physical river model, which were surveyed by W topography meter and the method of traditional survey probe. The studies have uncovered that the measurement accuracy of the W topographic meter is better than the method of traditional survey probe.(3) The accuracy of the multi-line structured light can be satisfied the requirements of general measurement in the small scope terrain. The topography survey is affected by the topography image distortion. However, the distortion error of the topography image can be effectively controlled if the calibration point density was reasonably arranged and adjusted. Taking the W topographic meter for example, it can be uncovered that the full scale of the of the multi-light structured planes is less than 5‰, and the absolute error is less than 1 mm. The error can be reduced evidently after the distortion adjusting.