Apollo教程笔记2 —— HDMap

无人驾驶车需要更详细、精确的地图
Apollo 高精度地图源码

Navigation Map vs. HD Map

A high definition map contains a huge amount of driving assistance information

• the accurate three-dimensional representation of the road network.
  • the layouts of intersections and the locations of signposts.
• a lot of semantic information.
  • The map may report what different colors of traffic lights mean.
  • It might also indicate the speed limit for a road.
  • and where the left turn lane begins.
• precision
  • Navigation Map: meter-level precision.
  • HD Map: centimeter-level precision.

Localization, Perception, Planing

video 1
无人驾驶车辆需要知道它在地图上的确切位置
首先，车辆可能会寻找地标。我们可以使用从各类传感器收集的数据，如摄像机图像数据，以及激光雷达收集的三维点云数据来查找地标。车辆将其收集的数据与其高精度地图上的已知地标进行比较。这一匹配过程是需要预处理、坐标转换和数据融合的复杂过程。

• Preprocessing eliminates inaccurate or poor quality data.
• Coordinate transformation converts the data from different perspectives(不同视角) into a uniform coordinate system(统一的坐标系).
• Data fusion merges data from different vehicle and different types of sensors.
  一旦无人驾驶车高度精确地确定了其位置，定位任务也就完成了。

video 2
perception software relies on the high-definition map.

• HD Map can feed traffic light positions to the rest of the software stack even if the sensors can’t detect the traffic light yet.
• HD Map will help the sensor narrow it’s detection scope. region of interest(ROI) can help us improve both detection accuracy and speed, saving computing resources for other tasks in the vehicle.

video 3
planning software relies on the high-definition map.

Apollo HD Map

Apollo HD Map Construction

HD Maps Service

https://data.apollo.auto/hd_map_intro?locale=en-us