Abstract: Laser SLAM digital simulation provides an efficient, controllable, and reproducible virtual test environment for the development of mobile measurement systems, significantly reducing the reliance on complex field tests. However, existing methods mostly rely on three-dimensional modeling, which face problems such as high modeling costs, geometric distortion, and difficulty in synchronously generating multi-sensor data. Therefore,a method for constructing a digital simulation system for mobile measurement based on laser simultaneous localization and mapping(SLAM) directly driven by real point clouds was proposed in this paper. The original laser point cloud data were directly transformed into a virtual environment with real scene characteristics. The behaviors and state changes of the sensors on the acquisition trajectory were simulated through the inverse digital modeling of the core sensors of laser radar and inertial measurement unit and the adoption of sparse voxel grid index and ray casting algorithm. The system supported the independent planning of B-spline curve trajectories and the flexible configuration of parameters such as scanning resolution and field of view and could synchronously generate spatiotemporally consistent raw laser radar data and inertial measurement unit data. Experimental results show that compared with traditional modeling-based simulation methods, the proposed method significantly reduces the cost and technical threshold of scene construction. Meanwhile, under the same scene and acquisition trajectory conditions, the geometric errors of point clouds, namely root mean square error(RMSE) and mean absolute error(MAE),decrease by approximately 18%～33% and 40%～48%, respectively, compared with the comparison methods. This indicates that the proposed method can effectively solve the high threshold problem of traditional modeling and provides a virtual test means with high geometric fidelity for SLAM algorithm evaluation and equipment development.

Key words: mobile measurement, simultaneous localization and mapping, device simulation, laser point cloud, laser radar, inertial measurement unit