A Low-Cost 3-D Imaging Device Using 2-D LiDAR and Reflectors

Laser techniques are widely used to perform topographic scenario surveys. However, in the absence of calibration in the Two-Dimensional (2-D)-based low-cost Three-Dimensional (3-D) scanning devices, a nonnegligible distortion between the ground truth and the reconstructed point cloud exists because of the imperfect structure of the 3-D scanning devices. Meanwhile, the real-time imaging performance is poor and insufficient to capture the shape of moving targets. Therefore, a simple but efficient 3-D scanning structure is developed to decrease the distortion. For real-time processing, the backward emitted laser beams are reflected by the reflectors and the then the reflected beams are available to detect the objects in front of the LiDAR. In the direction where objects of interest exist, the scanning frequency can be multiplied. Through a careful theoretical analysis, the spatial relationship between the points of the 2-D LiDAR, the placement of reflectors, and the 3-D objects is deduced. A solid experiment is performed in which several 3-D scanning devices are compared. It verifies the superiority of the proposed device in reducing the distortion and feasibility to alleviate the real-time processing problem.