# Open-Pit Map: An HD Map Data Model for Open-Pit Mines
## 1 Introduction  
High-definition maps (HD maps for short), due to the demand for autonomous driving technology, are recognized as an indispensable core technology for autonomous driving [1]. Compared with the electronic navigation maps that are currently in common use, HD maps not only have higher absolute coordinate accuracy, but also have more detailed road traffic elements and higher real-time performance. In autonomous driving systems, HD maps can compensate for the limitations of sensor detection, are not affected by severe weather, and provide centimeter-level precision information, greatly improving the accuracy of perception and positioning. Accurate prior information on the surrounding environment of the road also ensures that a vehicle can drive under fault handling and emergency conditions, and plays an important role in the process of perception, positioning, planning, decision-making, and control [2; 3]. An open-pit mine is a closed scene with simple traffic signs, low route complexity, low requirements for vehicle speed, and fewer pedestrians and other static distractions. The production and transportation operations of open-pit mines are planned and organized, and the value of the mining vehicle is high, meaning that mining enterprises have a high acceptance of high-cost and high-quality hardware. High-quality hardware leads to better implementation conditions for autonomous driving [4]. The realization of autonomous driving in open-pit mining areas can effectively reduce the safety risks caused by harsh environments and alleviate costs caused by labor shortages and labor cost increases, which is in line with the direction of green mines and intelligent mines [5]. HD maps are one of the core technologies that are needed to realize autonomous driving in open-pit mines. The support of HD maps in production operation, real-time path planning, real-time equipment scheduling, real-time safety control, and other businesses activities is crucial [6]. The creation of an HD map can not only meet the needs of autonomous driving, but also meet the needs of mine production management andproduction scheduling, which can effectively improve the effectiveness of comprehensive mining control. At present, the international standard formats for HD maps include the Navigation Data Standard (NDS), Open Street Map (OSM), Geographic Data Files (GDF), OpenDRIVE, Lanelets, etc. These standard formats have rich element layer information and attribute information for highway or urban road scenes. These formats are not suitable for direct application in open-pit mines [7], because the attributes of roads in the open-pit mines scene have a lot of changes due to business management and production needs, so the data model of HD maps for open-pit mines not only includes the road layer, lane layer, map feature layer, but also includes the scene element layer and traffic information layer for the open-pit mines. Some research on autonomous driving in open-pit mines has been conducted. [PERSON] [8] used unmanned aerial vehicles to automatically map indicators of safety, stability, and sustainability of rehabilitation efforts in coalmine sites. [PERSON] and [PERSON] [9] proposed a path planning method based on a high-precision digital map. [PERSON] et al. [10] proposed an HD map construction and update system for autonomous driving in open-pit mines. However, the structures and elements of the HD maps in these studies were neither detailed nor compatible for all of the common open-pit mining scenarios. In this article, common open-pit mining scenarios have been summarized. A universal HD map data model, Open-Pit Map, oriented toward data production and exchange was designed specifically for different scenarios in open-pit mines. Based on the data model, the map visualization tool, MapViewer, was developed, and its practicability and effectiveness were verified in a Chinese mine intelligent loading system project.