US 12,474,180 B2
Method and device for correcting errors in map data
Evan Hossain, Singapore (SG); Hao Wu, Singapore (SG); Xiaocheng Huang, Singapore (SG); Padarn George Wilson, Singapore (SG); and Guanfeng Wang, Singapore (SG)
Assigned to GRABTAXI HOLDINGS PTE. LTD., Singapore (SG)
Filed by GRABTAXI HOLDINGS PTE. LTD., Singapore (SG)
Filed on Oct. 10, 2023, as Appl. No. 18/484,069.
Application 18/484,069 is a continuation of application No. 17/636,854, granted, now 11,808,602, previously published as PCT/SG2020/050348, filed on Jun. 22, 2020.
Prior Publication US 2024/0035844 A1, Feb. 1, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. G01C 21/00 (2006.01); G06F 16/215 (2019.01); G06F 16/29 (2019.01); G08G 1/00 (2006.01); G08G 1/0968 (2006.01)
CPC G01C 21/3815 (2020.08) [G01C 21/3859 (2020.08); G01C 21/3867 (2020.08); G06F 16/215 (2019.01); G06F 16/29 (2019.01); G08G 1/096827 (2013.01); G08G 1/09685 (2013.01); G08G 1/202 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for operating a server to correct errors in map data, comprising:
downloading, to the server, map data specifying travel possibilities between locations;
generating a routing graph from the map data by assigning a vertex to each location and an edge from one vertex to another vertex if the map data specifies that it is possible to travel from the location to which the first vertex is assigned to the location to which the second vertex is assigned;
identifying the largest strongly connected component of the routing graph by identifying the largest component of the routing graph in which there is a path between all pairs of vertices of the component, and wherein the component is a subgraph of the routing graph;
identifying one or more additional strongly connected components of the routing graph;
detecting errors in the map data by identifying missing travel possibilities that are not in the map data which lead to missing connections between the one or more additional strongly connected components of the routing graph and the largest strongly connected component of the routing graph;
amending the map data by adding the identified missing travel possibilities;
transmitting the amended map data to a vehicle to control the navigation of the vehicle;
determining a quality indicator of the routing graph, the quality indicator based at least in part on the ratio of strongly connected components to the number of vertices in the routing graph;
storing the quality indicator as time series data associated with the map data;
monitoring the quality of the map data by tracking the quality indicator over time; and
generating an alarm signal when the quality indicator falls below a predetermined threshold.