Parking assistance system and parking assistance method

1. A parking assistance system of a vehicle, the system comprising:

a processor configured to:

determine whether or not the vehicle is in a stopped state based on information detected by a sensor included in the vehicle,

calculate current inclination information, which is an inclination of a road surface on which the vehicle is located, using an inclination sensor included in the vehicle, and identify the stopped state as a current stopped state, wherein the current inclination information is calculated based on sensor values measured at the current stopped state, wherein a current stopped time is a time duration for which the vehicle in the current stopped state remains stopped;

a memory configured to:

store the current inclination information as current traveling information when the current inclination information is less than predetermined threshold inclination information and previous traveling information is not stored in the memory, and

maintain previous inclination information as the current traveling information or update the previous traveling information by changing the previous inclination information to the current inclination information, depending on whether or not the current stopped time is greater than or equal to a first threshold time, wherein the previous inclination information is calculated based on sensor values measured at a previous stopped state, wherein a previous stopped time is a time duration for which the vehicle in the previous stopped state remains stopped, wherein the vehicle does not remain stopped between the previous and current stopped states; and

a controller configured to control the vehicle to move toward the parking space based on the current traveling information stored in the memory,

herein the controller controls the vehicle to move toward the parking space based on an engine driving torque, the engine driving torque being calculated by adding a compensating driving torque to a basic driving torque corresponding to an even road,

wherein the compensating driving torque is calculated based on the current traveling information, and changes as the current traveling information is updated, and

wherein when the current stopped time is less than the first threshold time, the memory is further configured to:

maintain the previous inclination information included in the previous traveling information when signs of the previous inclination information and the current inclination information are different from each other; and

update the previous traveling information by changing the previous inclination information included in the previous traveling information into the current inclination information when the signs of the previous inclination information and the current inclination information are the same as each other.

2. The parking assistance system of claim 1 , wherein the memory is further configured to

update the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information when the current stopped time is equal to or greater than the first threshold time and the current inclination information is less than the predetermined threshold inclination information.

3. The parking assistance system of claim 2 , wherein the inclination sensor includes an acceleration sensor, and the first threshold time is set based on oscillation information of the acceleration sensor.

4. The parking assistance system of claim 1 , wherein when the current stopped time is less than the first threshold time, the memory is further configured to:

maintain the previous inclination information included in the previous traveling information when a deviation, which is a difference between the previous inclination information and the current inclination information, is equal to or greater than a predetermined threshold deviation; and

update the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information when the deviation, which is the difference between the previous inclination information and the current inclination information, is less than the predetermined threshold deviation.

5. The parking assistance system of claim 1 , wherein the memory is further configured to update the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information only when: the current stopped time is less than the first threshold time; a deviation, which is a difference between the previous inclination information and the current inclination information, is less than a predetermined threshold deviation; and signs of the previous inclination information and the current inclination information are the same as each other.

6. The parking assistance system of claim 1 , further comprising a notification provider configured to indicate that it is impossible to park the vehicle in the parking space when the previous inclination information or the current inclination information calculated by the processor is greater than or equal to the predetermined threshold inclination information.

7. The parking assistance system of claim 1 , wherein the controller is further configured to terminate the parking assistance system when the previous inclination information or the current inclination information calculated by the processor is greater than or equal to the predetermined threshold inclination information.

8. A parking assistance method for searching for a parking space and assisting a driver in parking a vehicle in the parking space, the method comprising:

determining whether or not the vehicle is in a stopped state based on movement information of the vehicle;

calculating current inclination information, which is an inclination of a road surface on which the vehicle is located, using an inclination sensor included in the vehicle, and identifying the stopped state as a current stopped state, wherein the current inclination information is calculated based on sensor values measured at the current stopped state, wherein a current stopped time is a time duration for which the vehicle in the current stopped state remains stopped;

storing the current inclination information as current traveling information when the current inclination information is less than predetermined threshold inclination and previous traveling information is not stored in the memory, and maintaining previous inclination information as the current traveling information or updating the previous traveling information by changing the previous inclination information to the current inclination information, depending on whether or not the current stopped time is greater than or equal to a first threshold time, wherein the previous inclination information is calculated based on sensor values measured at a previous stopped state, wherein a previous stopped time is a time duration for which the vehicle in the previous stopped state remains stopped, wherein the vehicle does not remain stopped between the previous and current stopped states; and

controlling the vehicle to move toward the parking space based on the current traveling information stored in a memory,

wherein the controlling comprises controlling the vehicle to move toward the parking space based on an engine driving torque, the engine driving torque being calculated by adding a compensating driving torque to a basic driving torque corresponding to an even road,

wherein the compensating driving torque is calculated based on the current traveling information, and changes as the current traveling information is updated, and

wherein when the current stopped time is less than the first threshold time, the storing comprises:

maintaining the previous inclination information included in the previous traveling information when signs of the previous inclination information and the current inclination information are different from each other; and

updating the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information when the signs of the first inclination information and the current inclination information are the same as each other.

9. The method of claim 8 , wherein the storing further comprises

updating the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information when the current stopped time is equal to or greater than the first threshold time and the current inclination information is less than the predetermined threshold inclination information.

10. The method of claim 8 , wherein when the current stopped time is less than the first threshold time, the storing further comprises:

maintaining the previous inclination information included in the previous traveling information when a deviation, which is a difference between the previous inclination information and the current inclination information, is equal to or greater than a predetermined threshold deviation; and

updating the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information when the deviation, which is the difference between the previous inclination information and the current inclination information, is less than the predetermined threshold deviation.

11. The method of claim 8 , wherein the storing further comprises updating the previous traveling information by changing the previous inclination information included in the previous traveling information to the current inclination information only when: the current stopped time is less than the first threshold time; a deviation, which is the difference between the previous inclination information and the current inclination information, is less than a predetermined threshold deviation; and signs of the previous inclination information and the current inclination information are the same as each other.

12. The method of claim 8 , further comprising terminating parking assistance when the previous inclination information or the current inclination information calculated by the processor is greater than or equal to the predetermined threshold inclination information.