公开(公告)号：US11845466B2

公开(公告)日：2023-12-19

申请号：US17802148

申请日：2021-09-22

Applicant: SHANGHAITECH UNIVERSITY

Inventor： Qi Deng ,  Hao Sun ,  Yajun Ha ,  Hui Wang

IPC: B60W60/00

CPC classification number: B60W60/001 ,  B60W2420/52 ,  B60W2554/4049

Abstract: A normal distributions transform (NDT) method for LiDAR point cloud localization in unmanned driving is provided. The method proposes a non-recursive, memory-efficient data structure occupation-aware-voxel-structure (OAVS), which speeds up each search operation. Compared with a tree-based structure, the proposed data structure OAVS is easy to parallelize and consumes only about 1/10 of memory. Based on the data structure OAVS, the method proposes a semantic-assisted OAVS-based (SEO)-NDT algorithm, which significantly reduces the number of search operations, redefines a parameter affecting the number of search operations, and removes a redundant search operation. In addition, the method proposes a streaming field-programmable gate array (FPGA) accelerator architecture, which further improves the real-time and energy-saving performance of the SEO-NDT algorithm. The method meets the real-time and high-precision requirements of smart vehicles for three-dimensional (3D) lidar localization.

公开(公告)号：US11430200B2

公开(公告)日：2022-08-30

申请号：US17593852

申请日：2021-06-09

Applicant: SHANGHAITECH UNIVERSITY

Inventor： Hao Sun ,  Yajun Ha

IPC: G06V10/22 ,  G06V20/50 ,  G06T7/10

Abstract: An efficient K-nearest neighbor search algorithm for three-dimensional (3D) lidar point cloud in unmanned driving and a use of the foregoing K-nearest neighbor search algorithm in a point cloud map matching process in the unmanned driving are provided. A novel data structure for fast K-nearest neighbor search is used, such that each voxel or sub-voxel includes a proper quantity of points to reduce redundant search. The novel K-nearest neighbor search algorithm is based on a double segmentation voxel structure (DSVS) and a field programmable gate array (FPGA). By means of the novel K-nearest neighbor search algorithm, nearest neighbors are searched for only in a neighboring expected area near a search point, thereby reducing search of redundant points. In addition, an optimized data transmission and access policy is used, which makes the algorithm more fit the characteristic of the FPGA.