The principle of 3D laser scanning measurement is the optical triangle method: using a laser source with regular geometry to project onto the surface to be measured, the formed diffuse reflection image is imaged on an image sensor placed at a certain position in space, according to the triangle principle, Measure the spatial coordinates of the measured point

Once you are ready to work, you can perform the scan. First set up and start the instrument, you need to set the system parameters before scanning. System parameters include framing options (ball diameter, fast scan target mode, auto-photographing), units (including angle units and length units), video mode (scene is real-time or photo mode), system language (no Chinese). Then, the station is built, and the station is divided into three steps: leveling, station building, and rear view. When the station is completed, scanning measurements can be started, and point data and image data are collected.

You can choose to scan the instrument to set a 360° scan scene (the full range that the station can scan), or scan a portion of the 360° scan scene. The next step is to set or edit the scan parameters. When a scan target is selected, the scan parameter setting toolbar appears in the work area. The toolbar includes three parts: “Setting Method”, “Grid Value” and “Ranging Times”. After clicking the scan, the target scan is performed. After the target scan is completed, the check is completed, and the scan parameter settings are correct. After the error is saved, the scan result is saved. After the scan is completed, the above steps are repeated to perform the next station scan work.

Before the implementation of the scanning work, it is necessary to go to the site for exploration. During the survey, pay attention to the location of the existing control points, the preservation situation and the possibility of use, and the approximate scheme of the joint control of the control points. The location of the scanning site is determined based on the spatial distribution, shape, and accuracy and resolution required of the scanned object. According to the existing geodetic conditions and the position of the scanning site, the splicing method of the scanning model is considered, and the scene sketch is drawn, and the main scanning object is photographed.

The process of 3D scanning field operation is: surveying the scene → preparing the scanning implementation plan → scanning preparation (equipment, power supply, splicing standard) → placing the scanner → selecting the scanning area → setting the scanning parameters → model splicing.

The scanning implementation should include a plan for geodetic joint testing, the location of the scanning site and the orientation and positioning of the scanning, the target scanned at each scanning station, and the scanning resolution of each target. The workflow also includes scanning workflows, supply plans, staffing, and scanning construction organizations.