Device, method and update server for automatically updating navigation system

1. An automatic navigation-system update device, comprising:

a storage unit including a first storage module and a second storage module each of which stores map data and map version information, wherein the map data of the first storage module and the map data of the second storage module are initially identical to each other;

a communication unit configured to transmit the map version information extracted from the storage unit to an update server and to receive, from the update server, differential data of map data based on a difference between the map version information and latest map version information; and

a control unit configured to guide a route on the basis of the map data stored in the first storage module and to update the map data stored in the second storage module by reflecting the differential data, and the control unit further configured to copy all the updated map data of the second storage module into the first storage module to synchronize the map data of the first storage module or copy the differential data stored in the second storage module into the first storage module to update and synchronize the map data of the first storage module,

wherein the control unit guides the route only based on the map data stored in the second storage module when an operation of the first storage module is stopped.

2. The device of claim 1 , further comprising:

a power delivery unit configured to deliver electric power received from a power source of a motor vehicle, and

wherein the storage unit, the communication unit and the control unit are configured to receive the electric power from the power source through the power delivery unit when an engine of the motor vehicle is turned off.

3. The device of claim 2 , wherein the control unit is configured to update the map data of the first storage module based on the updated map data of the second storage module when the engine of the motor vehicle is turned off.

4. The device of claim 1 , wherein when guiding the route based on the map data stored in the second storage module, the control unit is configured to guide the route using the map data of the same version as a map version of the map data stored in the first storage module.

5. The device of claim 1 , wherein if it is determined through analysis of log data that a motor vehicle travels on a road along which a driver has driven a predetermined number of times or more, or it is determined through analysis of log data that the number of new guidance messages to be outputted is smaller than a predetermined number, the control unit updates the map data of the first storage module based on the updated map data of the second storage module immediately after updating the map data stored in the second storage module.

6. An automatic navigation-system update method, comprising:

a first step in which a control unit guides a route based on map data stored in a first storage module, extracts map data and map version information stored in a second storage module and transmits the map data and the map version information to an update server, wherein the map data of the first storage module and the map data of the second storage module are initially identical to each other;

a second step of receiving differential data based on a difference between the map version information and latest map version information from the update server via a communication unit;

a third step of updating the map data stored in the second storage module by reflecting the differential data;

a fourth step of copying all the updated map data of the second storage module into the first storage module to synchronize the map data of the first storage module or copying the differential data stored in the second storage module into the first storage module to update and synchronize the map data of the first storage module,

wherein the control unit guides the route only based on the map data stored in the second storage module when an operation of the first storage module is stopped.

7. The method of claim 6 ,

wherein, in the fourth step of, when an engine of a motor vehicle is turned off after the third step, electric power is received from a power source of the motor vehicle to update the map data of the first storage module based on the updated map data of the second storage module.

8. The method of claim 7 , wherein if the engine of the motor vehicle is turned on before the first storage module is completely updated in the fourth step, the control unit guides the route based on the map data stored in the second storage module and updates the map data stored in the first storage module.

9. The method of claim 6 , further comprising:

a step of receiving electric power from a power source of a motor vehicle if an engine of the motor vehicle is turned off in any of the first step, the second step and the third step.

10. The method of claim 6 , wherein the third step includes, immediately after updating the map data stored in the second storage module, allowing the control unit to update the map data of the first storage module based on the updated map data of the second storage module

if it is determined through analysis of log data that a motor vehicle travels on a road along which a driver has driven a predetermined number of times or more, or it is determined through analysis of log data that the number of new guidance messages to be outputted is smaller than a predetermined number.