Use of relative atlas in an autonomous vehicle

Patent metadata

Field	Value
Publication number	US-10503760-B2
Application number	US-201815940525-A
Country	US
Kind code	B2
Filing date	Mar 29, 2018
Priority date	Mar 29, 2018
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

A relative atlas may be used to lay out elements in a digital map used in the control of an autonomous vehicle. A vehicle pose for the autonomous vehicle within a geographical area may be determined, and the relative atlas may be accessed to identify elements in the geographical area and to determine relative poses between those elements. The elements may then be laid out within the digital map using the determined relative poses, e.g., for use in planning vehicle trajectories, for estimating the states of traffic controls, or for tracking and/or identifying dynamic objects, among other purposes.

First claim

What is claimed is:

1. A method of generating a digital map for use by an autonomous vehicle, the method comprising:
determining a vehicle pose for the autonomous vehicle within a geographical area;
accessing a relative atlas to identify a plurality of elements in the geographical area, wherein the relative atlas comprises a relative atlas graph, and wherein the relative atlas graph includes a plurality of element nodes for the plurality of elements and a plurality of edges, each of which connecting a pair of element nodes from among the plurality of element nodes and defining a relative pose between the associated elements for the pair of element nodes;
accessing the relative atlas to determine relative poses between the plurality of elements; and
laying out the plurality of elements within the digital map using the determined relative poses, wherein laying out the plurality of elements within the digital map using the determined relative poses includes:
laying out a first element among the plurality of elements at a first position in the relative map; and
laying out a second element among the plurality of elements at a second position in the relative map, including determining the second position from the first position using a relative pose between the first and second elements and defined in a first edge among the plurality of edges that connects a first element node for the first element with a second element node for the second element.

2. The method of claim 1 , wherein the plurality of element nodes are stored in a node table of a database and the plurality of edges are stored in an edge table of the database.

3. The method of claim 2 , wherein the database comprises a relational database.

4. The method of claim 1 , wherein each of the plurality of element nodes includes an identifier field including an identifier for the associated element thereof, and wherein each of the plurality of edges includes first and second identifier fields including identifiers for the associated elements for the pair of element nodes connected thereby.

5. The method of claim 1 , wherein each of the plurality of element nodes includes a type field specifying a type that characterizes the respective element node and wherein each of the plurality of edges includes a type field specifying a type that characterizes the respective edge.

6. The method of claim 5 , wherein each of the plurality of element nodes includes a payload field including element-specific data, and wherein each of the plurality of edges includes a payload field including edge-specific data.

7. The method of claim 6 , wherein the element-specific data in the payload field for the first element node is structured based upon the type specified in the type field of the first element node, and wherein the edge-specific data in the payload field for the first edge is structured based upon the type specified in the type field of the first edge.

8. The method of claim 1 , wherein the first edge includes a transformation function defining the relative pose between the first and second elements, and wherein determining the second position from the first position includes applying the transformation function.

9. The method of claim 1 , wherein accessing the relative atlas to determine the plurality of elements includes:
identifying a third element node for a third element that is positioned close to the vehicle pose; and
walking from the third element node to other element nodes among the plurality of nodes in the relative atlas graph using the plurality of edges.

10. The method of claim 9 , wherein laying out the plurality of elements within the digital map using the determined relative poses includes laying out the element corresponding to each other element node by applying the relative pose defined by each edge interposed between the third element node and the other element node.

11. The method of claim 1 , wherein the relative atlas graph further includes a plurality of tile nodes for the geographical area, each tile node corresponding to a tile representing a region of the geographical area, and a second plurality of edges, each edge in the second plurality of edges connecting an element node from among the plurality of element nodes to a tile node from among the plurality of tile nodes and defining a relative pose of the associated element for the connected element node within a frame of reference for the connected tile node.

12. The method of claim 11 , wherein determining the vehicle pose includes determining the vehicle pose within the frame of reference in a first tile defined by a first tile node among the plurality of tile nodes.

13. The method of claim 12 , wherein the first tile node includes geometry data defining a surface model for at least a portion of the region of the geographical area represented by the first tile node, and wherein determining the vehicle pose further includes:
assembling received sensor data into a point cloud;
aligning the point cloud with the surface model; and
determining the vehicle pose based on the alignment of the point cloud with the surface model.

14. The method of claim 13 , further comprising nudging an element represented by a third element node among the plurality of element nodes based upon the alignment of the point cloud with the surface model, including updating a relative pose for an edge connected to the first element node.

15. The method of claim 14 , further comprising propagating the updated relative pose for the edge connected to the third element node to a remote computer system and/or another autonomous vehicle.

16. The method of claim 13 , wherein the surface model is a first surface model, and wherein determining the vehicle pose further includes:
aligning the point cloud with a second surface model for a second tile defined by geometry data stored in a second tile node for the second tile; and
selecting between the first tile and the second tile from which to determine the vehicle pose based upon the alignments of the point cloud with the first and second surface models.

17. The method of claim 12 , further comprising determining an active tile for the autonomous vehicle, including:
determining a location of the autonomous vehicle based upon a satellite navigation sensor; and
selecting an active tile node from among the plurality of tiles nodes using the determined location.

18. The method of claim 17 , wherein the relative atlas graph further includes a fixed reference node defining a fixed reference point and a reference frame therefor and a plurality of fixed reference edges connecting the plurality of tile nodes to the fixed reference node and defining relative poses between respective tiles for the plurality of tile nodes and the fixed reference point, wherein selecting the active tile node includes:
determining the location of the autonomous vehicle in the reference frame for the fixed reference point; and
identifying one or more nearby tiles to the determined location using the relative poses defined by the fixed reference edges.

19. The method of claim 11 , wherein the relative atlas graph further includes tile-and-tile edges connecting pairs of tile nodes and defining relative poses between the tiles represented thereby.

20. The method of claim 19 , wherein the relative atlas graph further includes a fixed reference node defining a fixed reference point and a reference frame therefor and a plurality of fixed reference edges connecting the plurality of tile nodes to the fixed reference n

Assignees

• Aurora Innovation Inc

Inventors

• Eade Ethan
• Bode Michael
• Bagnell James Andrew

Classifications

• G06V10/426

  Graphical representations · CPC title

• G06V20/56

  exterior to a vehicle by using sensors mounted on the vehicle · CPC title

• G06T2207/30252

  Vehicle exterior; Vicinity of vehicle · CPC title

• G06F16/29 Primary

  Geographical information databases · CPC title

• G01C21/30

  Map- or contour-matching · CPC title