Parking assistance device and parking assistance method

1. A parking assistance device configured to assist a parking operation in which a vehicle is perpendicularly parked in a parkable area, comprising a controller configured to:

generate a route along which the vehicle is to travel forward from a parking start position to a reversing position and then travel from the reversing position to the parkable area;

obtain a width of a vehicle passage which the parkable area faces;

look up attitude angles of the vehicle at the reversing position to enable generation of the route in which a front portion of the vehicle will not interfere at the reversing position with an obstacle adjacent to the vehicle passage in a width direction of the vehicle passage, wherein the attitude angles are based on the width of the vehicle passage; and

automatically control a steering operation of the vehicle to guide the vehicle into the parkable area along the route that is generated using the attitude angles, wherein the route is generated prior to the vehicle traveling the route.

2. The parking assistance device according to claim 1 , wherein the attitude angles are any of angles relative to a travel direction of the vehicle at parking start, angles relative to the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage, and angles relative to an obstacle adjacent to the parkable area in a width direction of the parkable area.

3. The parking assistance device according to claim 1 , wherein the controller is further configured to:

look up the attitude angles at the reversing position in a descending order starting from the attitude angle at completion of parking; and

select the largest attitude angle from the attitude angles of the vehicle which enable generation of the route in which the front portion of the vehicle at the reversing position will not interfere at the reversing position with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage.

4. The parking assistance device according to claim 1 , wherein the controller is further configured to:

look up the attitude angles at the reversing position in a descending order starting from a start attitude angle; and

set the start attitude angle such that the smaller the width of the vehicle passage is, the smaller the start attitude angle is.

5. The parking assistance device according to claim 1 , wherein the controller is further configured to:

obtain a depth of the vehicle passage; and

look up the attitude angles of the vehicle at the reversing position based on the width of the vehicle passage and the depth of the vehicle passage to enable generation of the route in which the front portion of the vehicle will not interfere at the reversing position with obstacles adjacent to the vehicle passage in the width direction and a depth direction of the vehicle passage.

6. The parking assistance device according to claim 5 , wherein the controller is configured to select the attitude angle such that the smaller the depth of the vehicle passage is, the larger the selected attitude angle is.

7. The parking assistance device according to claim 5 , wherein

when the depth of the vehicle passage is larger than the width of the vehicle passage, the controller is configured to look up the attitude angles at the reversing position in an ascending order starting from zero, and

when the depth of the vehicle passage is equal to or smaller than the width of the vehicle passage, the controller is configured to look up the attitude angles at the reversing position in a descending order starting from the attitude angle at completion of parking.

8. The parking assistance device according to claim 1 , wherein when the route in which the front portion of the vehicle will not interfere at the reversing position with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage is impossible to generate by looking up the attitude angles of the vehicle at the reversing position, the controller is configured to:

move a target parking position in an entering direction of the vehicle, from an end of the parkable area on a side from which the vehicle enters; and

look up the attitude angles of the vehicle at the reversing position, based on the moved target parking position.

9. The parking assistance device according to claim 8 , wherein the controller is further configured to:

obtain a width of the parkable area; and

select the target parking position to which a movement amount is the smallest in the entering direction of the vehicle, from the target parking positions which enable generation of the routes in which the vehicle will not interfere with the obstacle adjacent to the parkable area in the width direction of the parkable area.

10. The parking assistance device according to claim 8 , wherein when the route in which the front portion of the vehicle will not interfere at the reversing position with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage is impossible to generate by moving the target parking position in the entering direction of the vehicle from the end of the parkable area on the side from which the vehicle enters and by looking up the attitude angles of the vehicle at the reversing position, the controller is configured to determine that the route along which the vehicle is to travel to the parkable area via the reversing position is impossible to generate.

11. The parking assistance device according to claim 1 , wherein the controller is further configured to:

set the attitude angle of the vehicle at the reversing position,

determine whether the front portion of the vehicle will interfere with the obstacle adjacent to the vehicle passage, at the reversing position in the route generated based on the set attitude angle, and when determining that the front portion will interfere,

change the attitude angle of the vehicle at the reversing position; and

determine whether the front portion of the vehicle will interfere with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage, at the reversing position in the route generated based on the changed attitude angle.

12. The parking assistance device according to claim 1 , wherein the controller is further configured to look up target parking positions in the parkable area based on the width of the vehicle passage to enable generation of the route in which the front portion of the vehicle will not interfere at the reversing position with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage.

13. A parking assistance method of assisting a parking operation in which a vehicle is perpendicularly parked in a parkable area, comprising:

generating a route along which the vehicle is to travel forward from a parking start position to a reversing position and then travel from the reversing position to the parkable area;

obtaining a width of a vehicle passage which the parkable area faces;

looking up attitude angles of the vehicle at the reversing position to enable generation of the route in which a front portion of the vehicle will not interfere at the reversing position with an obstacle adjacent to the vehicle passage in a width direction of the vehicle passage, wherein the attitude angles are based on the width of the vehicle passage; and

automatically controlling a steering operation of the vehicle to guide the vehicle into the parkable area along the route that is generated using the attitude angles, wherein the route is generated prior to the vehicle traveling the route.

14. The parking assistance device of claim 1 , wherein the route comprises travelling in a first direction from the parking start position to the reversing position and travelling in a second direction from the reversing position to the parkable area.

15. The parking assistance device of claim 1 , wherein the attitude angles comprise angles relative to obstacles adjacent to the vehicle passage in the width direction.

16. The parking assistance device of claim 15 , wherein the attitude angles further comprise angles relative to obstacles adjacent to the parkable area in the width direction.

17. The parking assistance device of claim 1 , wherein the attitude angles comprise angles relative to obstacles adjacent to the parkable area in the width direction.

18. A parking assistance device configured to assist a parking operation in which a vehicle is perpendicularly parked in a parkable area, comprising a controller configured to:

generate a route along which the vehicle is to travel to the parkable area via a reversing position;

obtain a width of a vehicle passage that the parkable area faces;

look up attitude angles of the vehicle at the reversing position based on the width of the vehicle passage to enable generation of the route in which a front portion of the vehicle will not interfere at the reversing position with an obstacle adjacent to the vehicle passage in a width direction of the vehicle passage, wherein the attitude angles are looked up in a descending order starting from at least one of the attitude angle at completion of parking or a start attitude angle;

if the attitude angles are looked up in a descending order starting from the attitude angle at the completion of parking, select the largest attitude angle from the attitude angles of the vehicle that enable generation of the route in which the front portion of the vehicle at the reversing position will not interfere with the obstacle adjacent to the vehicle passage in the width direction of the vehicle passage; and

if the attitude angles are looked up in a descending order starting from a start attitude angle, set the start attitude angle such that the smaller the width of the vehicle passage, the smaller the start attitude angle is.