Patent ID: 11906326
Assignee: DENSO CORPORATION
Field: Control (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A map update method comprising:
transmitting, by an onboard terminal, a confirmation request as to whether updated data that is map data for updating is available;
in response to the confirmation request being received from the onboard terminal, transmitting, by a map update server, a confirmation result to enable the onboard terminal to update map data in the onboard terminal;
in response to the confirmation request being received from the onboard terminal in a state in which the updated data after start of a temporary road change is available, distributing, by the map update server, the updated data and transmitting, by the map update server, the confirmation result to instruct the onboard terminal to temporarily use the updated data;
in response to the confirmation request being received from the onboard terminal in a state in which the updated data after end of a temporary road change is available, transmitting, by the map update server, the confirmation result to instruct the onboard terminal to use the updated data from before the start of the temporary road change;
in response to the confirmation result from the map update server to instruct the onboard terminal to temporarily use the updated data, using, by the onboard terminal, the updated data that has already been distributed;
in response to the confirmation result from the map update server to instruct the onboard terminal to use the updated data from before the start of the temporary road change, using, by the onboard terminal, map data from before the start of the temporary road change instead of the updated data;
acquiring, by the map update server, work information;
setting, by the map update server, a state in which the map update server acquires the work information to be a state in which the temporary road change is started;
setting a status of management information to an invalid state, by the map update server, in response to the management information being in an initial state;
setting the status of management information to a prepared state, by the map update server, in response to the work information being acquired when the status of management information indicates the invalid state;
in response to a road change occurring when the status of management information indicates the prepared state, updating the map data to the updated data and setting the status of management information to a saved state, by the map update server;
in response to a road change occurring in the saved state, updating the map data to the updated data, by the map update server,
when the updated data matches the map data from before the temporary road change, setting the status of management information to a reusable state, by the map update server, and
when the updated data does not match the map data from before the temporary road change, discarding the map data that is saved and setting the status of management information to the invalid state, by the map update server;

in response to a road change occurring when the status of management information indicates the reusable state, updating the map data to the updated data, discarding the saved map data, and setting the status of management information to the invalid state, by the map update server;
when a newest map is requested by the onboard terminal,
distributing the updated data to which a map version is added and instructing the onboard terminal to update the map data, by the map update server, when the status of management information indicates the invalid state,
instructing the onboard terminal not to update the map data, by the map update server, when the status of management information indicates the prepared state,
distributing the updated data to which a map version is added and instructing the onboard terminal to save the map data, by the map update server, when the status of management information indicates the saved state, and
instructing the onboard terminal to reuse the map data and distributing the map version, by the map update server, when the status of management information indicates the reusable state; and

when the updated data is requested to the map update server,
performing no operation, by the onboard terminal, in response to being instructed not to update the map data,
updating the map data to the updated data distributed by the map update server, by the onboard terminal, in response to being instructed to update the map data,
saving the map data and updating to the updated data, by the onboard terminal, in response to being instructed to save the map data, and
restoring the saved map data and updating an own map version, by the onboard terminal, in response to being instructed to reuse the map data.