Parking assist apparatus

A parking assist apparatus sets a target position on a traffic lane, based on vehicle surrounding information, calculates a moving route, and executes a parking assist control of moving an own vehicle along the moving route. The parking assist control includes a steering angle control, a driving force control, and a braking force control. The parking assist apparatus changes the stopping number of stopping the own vehicle, based on the vehicle surrounding information while moving the own vehicle along the moving route.

BACKGROUND

Field

The invention relates to a parking assist apparatus which executes a parking assist control of moving a parked vehicle to a traffic lane.

Description of the Related Art

There has been proposed a parking assist apparatus which detects surrounding situation around a vehicle with surrounding sensors such as cameras and sensors mounted on the vehicle and executes a parking assist control of moving the vehicle to a target position set, depending on the detected surrounding situation (for example, see JP 2015-174586 A). The parking assist control includes a steering angle control of controlling a steering angle of the vehicle, a driving force control of controlling driving force applied to the vehicle, and a braking force control of controlling braking force applied to the vehicle.

When an own vehicle is moved or pulled out to a traffic lane by the parking assist control, objects such as pedestrians and other vehicles may approach the own vehicle from the left side and/or the right side of the own vehicle. Therefore, the own vehicle may be stopped several times while the parking assist control is being executed. Thereby, a driver of the own vehicle may have chances to confirm a situation of the traffic lane. In this regard, the own vehicle may be stopped even when the driver has already confirmed the situation of the traffic lane. In this case, the driver may feel bothersome.

SUMMARY

The invention has been made for solving the aforementioned problems. An object of the invention is to provide a parking assist apparatus which can change the stopping number of stopping the own vehicle, depending on the surrounding situation around the own vehicle while the parking assist control is being executed.

A parking assist apparatus according to the invention comprises an information acquiring apparatus and an electronic control unit. The information acquiring apparatus acquires vehicle surrounding information including information on objects around an own vehicle which is parked. The electronic control unit is configured to, in response to an assistance request being generated, set a target position on a traffic lane to which the electronic control unit moves the own vehicle, based on the vehicle surrounding information. Further, the electronic control unit is configured to calculate a moving route along which the electronic control unit moves the own vehicle from a current position of the own vehicle to the target position. Furthermore, the electronic control unit is configured to execute a parking assist control of moving the own vehicle along the moving route.

According to the invention, the parking assist control includes (i) a steering angle control of changing a steering angle of the own vehicle, (ii) a driving force control of controlling driving force of the own vehicle, and (iii) a braking force control of controlling braking force of the own vehicle.

Further, the electronic control unit is configured to change the stopping number of stopping the own vehicle, based on the vehicle surrounding information while the electronic control unit moves the own vehicle along the moving route.

With the invention, the parking assist apparatus can prevent the driver from feeling bothersome and provide the driver with changes to confirm the situation of the traffic lane.

According an aspect of the invention, the electronic control unit may be configured to detect a first object to a first side of the own vehicle, based on the vehicle surrounding information, the first side being one of the right side and the left side of the own vehicle and detect a second object to a second side of the own vehicle, based on the vehicle surrounding information, the second side being the other of the right side and the left side of the own vehicle. In this aspect, the electronic control unit may be configured to change the stopping number, based on a positional relationship between (i) a vehicle end portion which is an end portion of the own vehicle at the side of the traffic lane, (ii) a first end portion which is an end portion of the first object at the side of the traffic lane, and (iii) a second end portion which is an end portion of the second object at the side of the traffic lane.

According to another aspect of the invention, the electronic control unit may be configured to set the stopping number to two when the electronic control unit determines, based on the positional relationship, that a current situation is a first situation. In this case, the first situation may include a situation that (i) the first object and the second object interrupt a field of view from the own vehicle, and (ii) a distance in a longitudinal direction of the own vehicle between the first end portion and the second end portion is longer than a predetermined threshold. Further, in this case, the electronic control unit may be configured to stop the own vehicle when the vehicle end portion reaches a position forward by a predetermined distance from the first end portion while the electronic control unit moves the own vehicle along the moving route, and stop the own vehicle when the vehicle end portion reaches a position forward by the predetermined distance from the second end portion while the electronic control unit moves the own vehicle along the moving route.

The field of view from the own vehicle corresponds to a scope on the traffic lane which can be confirmed from the own vehicle. In particular, the field of view from the own vehicle corresponds to a scope on the traffic lane which a driver of the own vehicle can see or the information acquiring apparatus such as a camera can detect.

With this aspect of the invention, the parking assist apparatus stops the own vehicle twice in the first situation. In particular, the parking assist apparatus stops the own vehicle at a position at which the field of view from the own vehicle is not interrupted by the first object and stops the own vehicle at a position at which the field of view from the own vehicle is not interrupted by the second object. Thus, the driver can surely confirm the situation of the traffic lane.

According to further another aspect of the invention, the electronic control unit may be configured to set the stopping number to one when the electronic control unit determines, based on the positional relationship, that a current situation is a second situation. In this case, the second situation may include (i) a situation that the first object and the second object interrupt a field of view from the own vehicle, and a distance in a longitudinal direction of the own vehicle between the first end portion and the second end portion is equal to or smaller than a predetermined threshold, and (i) a situation that only the first object interrupts the field of view from the own vehicle. Further, in this case, the electronic control unit may be configured to stop the own vehicle when the vehicle end portion reaches a position forward by a predetermined distance from the first end portion while the electronic control unit moves the own vehicle along the moving route.

With this aspect of the invention, the parking assist apparatus stops the own vehicle once at a position at which the driver can confirm the objects which approach the own vehicle from the right side and the left side of the own vehicle. Thus, even when the own vehicle is stopped only once, the driver can sufficiently confirm the situation of the traffic lane. Thus, the parking assist apparatus can prevent the driver from feeling bothersome and provide the driver with changes to confirm the situation of the traffic lane.

According to further another aspect of the invention, the electronic control unit may be configured to set the stopping number to zero when the electronic control unit determines, based on the positional relationship, that a current situation is a third situation. In this case, the third situation may include a situation that the first object and the second object do not interrupt a field of view from the own vehicle.

With this aspect of the invention, the parking assist apparatus does not stop the own vehicle in the third situation. Thus, the parking assist apparatus can prevent the driver from feeling bothersome.

According to further another aspect of the invention, the electronic control unit may be configured to calculate, as the positional relationship, (i) a first distance in a longitudinal direction of the own vehicle between the vehicle end portion and the first end portion, (ii) a second distance in the longitudinal direction of the own vehicle between the vehicle end portion and the second end portion, and (iii) a third distance in the longitudinal direction of the own vehicle between the first end portion and the second end portion.

According to one or more of embodiments, the electronic control unit may be realized by a micro-processor which is programmed so as to execute one or more functions described in the specification. Further, according to one or more of the embodiments, the electronic control unit may be entirely or partially realized by a hardware configured by an integrated circuit such as ASIC detected to one or more applications.

Elements of the invention are not limited to elements of embodiments and modified examples of the invention described with reference to the drawings. The other objects, features and accompanied advantages of the invention can be easily understood from the embodiments and the modified examples of the invention.

DESCRIPTION OF THE EMBODIMENTS

Below, one or more embodiments of the invention will be described with reference to the drawings. A parking assist apparatus is applied to an own vehicle SV (seeFIG.2).

As shown inFIG.1, the parking assist apparatus includes a parking assist ECU10. The parking assist ECU10includes a micro-computer which includes a CPU10a, a RAM10b, a ROM10c, and an interface (I/F)10d. In this specification, ECU stands for electronic control unit. The ECU includes a micro-computer which includes a CPU, a RAM, a ROM, and an interface. The CPU realizes various functions by executing instructions stored in the ROM.

The parking assist ECU10is electrically connected to an engine ECU20, a brake ECU30, an SBW (Shift-by-Wire) ECU40, an electric power steering ECU (hereinafter, will be referred to as “EPS ECU”)50, and a navigation ECU60via a CAN (Controller Area Network)90. The ECUs10,20,30,40,50, and60are electrically connected so as to send and receive information to and from each other via the CAN90. Thus, detection values of sensors electrically connected to one of the ECUs10,20,30,40,50, and60can be sent to the remaining of the ECUs10,20,30,40,50, and60.

The engine ECU20is electrically connected to (i) engine state amount sensors (not shown) which include an accelerator pedal operation amount sensor21and (ii) engine actuators22. The accelerator pedal operation amount sensor21detects an operation amount or an accelerator opening degree of an accelerator pedal21aand generates a signal which represents an accelerator pedal operation amount AP.

The engine ECU20drives the engine actuators22, based on the accelerator pedal operation amount AP and driving state amounts such as an engine speed detected by the engine state amount sensor other than the accelerator pedal operation amount sensor21. Thereby, the engine ECU20can change an engine-generated torque which an internal combustion engine23generates. The engine-generated torque is transmitted to driven wheels of the own vehicle via a transmission24. Thus, the engine ECU20can control driving force applied to the own vehicle SV by controlling the engine actuators22.

When the own vehicle SV is a hybrid vehicle, the engine ECU20can control the driving force generated by one or both of the internal combustion engine and at least one electric motor as vehicle driving sources. When the own vehicle SV is an electric vehicle, the engine ECU20can control the driving force generated by at least one electric motor as the vehicle driving source.

The brake ECU30is electrically connected to (i) a brake pedal operation amount sensor31and (ii) brake actuators32. The brake pedal operation amount sensor31detects an operation amount of a brake pedal31aand outputs a signal which represents a brake pedal operation amount BP.

Braking force or braking torque applied to wheels of the own vehicle SV is controlled by the brake actuators32. The brake actuators32adjust hydraulic pressure applied to wheel cylinders (not shown) of friction brake mechanisms33in response to commands from the brake ECU30and control braking pressure of the wheel cylinders by the hydraulic pressure. Thereby, the wheel cylinders generate friction braking force applied to the wheels of the own vehicle SV. Thus, the brake ECU30can control the braking force applied to the own vehicle SV by controlling the brake actuators32.

The SBW ECU40is electrically connected to a shift lever sensor41and an SBW actuator42. The shift lever sensor41detects a position of a shift lever. The SBW ECU40receives the position of the shift lever from the shift lever sensor41and controls the SBW actuator42, based on the position of the shift lever. The SBW actuator42controls a shift changing mechanism in response to commands from the SBW ECU40to change a shift position of the transmission24to one of shift positions.

In this embodiment, the shift positions include (i) a parking position in which the driving force is not transmitted to the driven wheels, and the own vehicle SV is mechanically locked at a stopped position, (ii) a neutral position in which the driving force is not transmitted to the driven wheels, and the own vehicle SV is not mechanically locked at the stopped position, (iii) a forward moving position in which the driving force to drive the own vehicle SV forward is transmitted to the driven wheels, and (iv) a rearward moving position in which the driving force to drive the own vehicle SV rearward is transmitted to the driven wheels.

In particular, when a position of the shift lever is “P”, the SBW ECU40drives the SBW actuator42to control the shift changing mechanism43to set the shift position of the transmission24to the parking position. When the position of the shift lever is “N”, the SBW ECU40drives the SBW actuator42to control the shift changing mechanism43to set the shift position of the transmission24to the neutral position. When the position of the shift lever is “D”, the SBW ECU40drives the SBW actuator42to control the shift changing mechanism43to set the shift position of the transmission24to the forward moving position. When the position of the shift lever is “R”, the SBW ECU40drives the SBW actuator42to control the shift changing mechanism43to set the shift position of the transmission24to the rearward moving position.

The EPS ECU50is electrically connected to an assist motor (M)51. The assist motor51is installed in a steering mechanism52. The steering mechanism52is a mechanism which steers steered wheels of the own vehicle SV in response to a rotation operation applied to a steering wheel SW. The steering mechanism52includes the steering wheel SW, a steering shaft US connected to the steering wheel SW, and a steering gear mechanism (not shown). The EPS ECU50detects steering torque which the driver of the own vehicle inputs to the steering wheel SW by a steering torque sensor53provided on the steering shaft US and drives the assist motor51, based on the steering torque. The EPS ECU50applies steering torque or steering assist torque to the steering mechanism52by driving the assist motor51and thereby assists the steering operation of the driver.

In addition, when the EPS ECU50receives steering commands from the parking assist ECU10via the CAN90while a parking assist control (described later) is being executed, the EPS ECU50drives the assist motor51, based on the steering torque specified by the steering commands. This steering torque is different from the steering assist torque. This steering torque is torque applied to the steering mechanism52in response to the steering commands from the parking assist ECU10without the steering operation performed by the driver. This torque changes steered angles of the steered wheels (i.e., a steering angle) of the own vehicle SV.

The navigation ECU60includes a GPS receiver61, a map database62, and a touch panel63. The GPS receiver61receives GPS signals used to detect a latitude and a longitude of a position of the own vehicle SV. The map database62stores map information. The navigation ECU60executes various calculation processes, based on (i) the latitude and the longitude of the position of the own vehicle SV and (ii) the map information. Then, the navigation ECU60displays the position of the own vehicle SV on a map on the touch panel63. Hereinafter, a displaying mode of displaying the position of the own vehicle SV on the map on the touch panel63will be referred to as “first mode” or “navigation mode”. The touch panel63is a touch panel type of a display which can display a map and images.

The displaying mode of the touch panel63includes a second mode or a parking assist mode in addition to the first mode. The second mode is the displaying mode which is used when the parking assist control is executed and displays various images which display surrounding situation around the own vehicle SV as described later. When an assistance request is generated as described later, the displaying mode is changed from the first mode to the second mode.

The parking assist ECU10is electrically connected to surrounding sensors70. The surrounding sensors70acquire vehicle surrounding information. The vehicle surrounding information includes information on standing objects around the own vehicle SV and information on line markings or parking bay markings on road surface or ground surface around the own vehicle SV. The standing objects are, for example, moving objects such as vehicles, pedestrians, and bicycles, and fixed objects such as guard rails and fences. Hereinafter, the standing objects will be simply referred to as “objects”. The surrounding sensors70include ultrasonic wave sensors71ato71hand cameras72ato72d. The ultrasonic wave sensors71ato71hwill be collectively referred to as “ultrasonic wave sensors71”. The cameras72ato72dwill be collectively referred to as “cameras72”. The surrounding sensors70will be also referred to as “information acquiring apparatus which acquires the vehicle surrounding information”.

The ultrasonic wave sensors71transmit ultrasonic waves to a predetermined scope around the own vehicle SV in a pulsed manner and receive reflected waves which are reflected by the objects. The ultrasonic wave sensors71acquire information on (i) reflection points which are points on the object by which the transmitted ultrasonic waves are reflected and (ii) a distance between the ultrasonic wave sensor71and the reflection point, based on time taken from transmitting the ultrasonic wave to receive the reflected wave. The ultrasonic wave sensors71output the acquired information to the parking assist ECU10.

As shown inFIG.2, four ultrasonic wave sensors71ato71dare provided on a front bumper201of the own vehicle SV, spaced from each other in a width direction of the own vehicle SV. In addition, four ultrasonic wave sensors71eto71hare provided on a rear bumper202of the own vehicle SV, spaced from each other in the width direction of the own vehicle SV.

The cameras72are digital cameras which include imaging elements such as CCD (charge coupled device) or CIS (CMOS image sensor). The cameras72output image data on a surrounding area around the own vehicle SV with a predetermined frame rate. The cameras72take images of the surrounding situation (including positions and shapes of the objects, and positions and shapes of the line markings) around the own vehicle SV. Then, the cameras72output the image data to the parking assist ECU10.

As shown inFIG.2, the camera72ais mounted on a generally center portion of the front bumper201in the width direction of the own vehicle SV. The camera72atakes images of a forward area ahead of the own vehicle SV. The camera72bis mounted on a wall portion of a rear trunk203or a rear boot of a rear portion of a vehicle body200. The camera72btakes images of a rear area behind the own vehicle SV. The camera72cis mounted on a right door mirror204. The camera72ctakes images of a right area rightward from the own vehicle SV. The camera72dis mounted on a left door mirror205. The camera72dtakes images of a left area leftward from the own vehicle SV. Below, the image data acquired by the cameras72a,72b,72c, and72dwill be also referred to as “forward image data”, “rear image data”, “right image data” and “left image data”, respectively.

The parking assist ECU10receives the information from the ultrasonic wave sensors71each time a predetermined time (for the convenience, this predetermined time will be also referred to as “first time”) elapses. The parking assist ECU10plots the information (i.e., positions of the reflection points at which the ultrasonic waves are reflected) on a two-dimension map. The two-dimension map is a plan view which includes (i) an origin which corresponds to the position of the own vehicle SV, (ii) an X axis which corresponds to a moving direction of the own vehicle SV, and (iii) a Y axis which corresponds to a leftward direction of the own vehicle SV. The position of the own vehicle SV is a predetermined geometric center position on a planar view of the own vehicle SV. The parking assist ECU10detects the objects around the own vehicle SV, based on shapes defined by a group of the reflection points on the two-dimension map. Then, the parking assist ECU10determines positions (distances and orientations) and shapes of the objects with respect to the own vehicle SV.

The position of the own vehicle SV may be another particular position on the own vehicle SV, for example, a center position between a left front wheel and a right front wheel of the own vehicle SV or a center position between a left rear wheel and a right rear wheel of the own vehicle SV.

In addition, the parking assist ECU10acquires the image data from the cameras72each time the first time elapses. The parking assist ECU10detects the objects around the own vehicle SV by analyzing the image data from the cameras72. Then, the parking assist ECU10determines the positions (the distances and the orientations) and the shapes of the objects with respect to the own vehicle SV. The parking assist ECU10draws, on the two-dimension map, the objects determined or detected, based on the image data. Thus, the parking assist ECU10can detect the objects around the own vehicle SV in a predetermined distance area from the position of the own vehicle SV, based on the information on the two-dimension map.

The parking assist ECU10detects an area where no objects exist around the own vehicle SV, based on the information on the two-dimension map. When the area where no objects exist has a size and a shape to which the own vehicle SV is allowed to move, the parking assist ECU10determines the area where no objects exist as a pulling-out-permitted area or a parking-permitted area.

Further, the parking assist ECU10is electrically connected to a vehicle moving speed sensor81, a parking assist switch82, and a speaker83.

The vehicle moving speed sensor81detects a moving speed of the own vehicle SV and outputs a signal which represents the moving speed.

The parking assist switch82is a switch which is pressed by the driver when the driver requests the parking assist ECU10to execute the parking assist control, i.e., when the driver generates the assistance request described later.

The speaker83generates voice when the speaker83receives an announcement command from the parking assist ECU10.

Next, screens images (hereinafter, will be referred to as “assist mode screen images”) which are displayed on the touch panel63when the displaying mode is the second mode, will be described. As shown inFIG.3, the assist mode screen image has a first displaying area301, a second displaying area302, and a third displaying area303.

When the displaying mode is the second mode, the parking assist ECU10displays a point-of-view image and a moving direction image (described later) in the assist mode screen image. Below, methods of producing the point-of-view image and the moving direction image will be briefly described.

The parking assist ECU10produces the point-of-view image, based on the image data (i.e., the forward image data, the rear image data, the right image data, and the left image data) acquired by the cameras72. The point-of-view image corresponds to an image of the own vehicle SV and an area surrounding the own vehicle SV from a set virtual point of view. The method of producing the point-of-view image is known (for example, see JP 2012-217000 A and JP 2013-021468 A). For example, the point-of-view image is an image taken by viewing the own vehicle SV from directly above. The point-of-view image is also referred to as “perspective image”.

The parking assist ECU10produces the moving direction image, based on the forward image data and the rear image data. The moving direction image is an image which displays an area in the moving direction of the own vehicle SV. When the parking assist ECU10moves the own vehicle SV forward, the parking assist ECU10produces the moving direction image which displays a forward area ahead of the own vehicle SV, based on the forward image data. On the other hand, when the parking assist ECU10moves the own vehicle SV rearward, the parking assist ECU10produces the moving direction image which displays a rear area behind the own vehicle SV, based on the rear image data.

As shown inFIG.3, the parking assist ECU10displays a perspective image401in the first displaying area301and displays a moving direction image402in the second displaying area302.

<Processes of Parking Assist Control>

The parking assist ECU10monitors the position of the shift lever and an operation applied to the parking assist switch82and selects an assist mode from a pulling-out mode, a double-parking mode, and a parallel-parking mode.

The pulling-out mode is a mode which carries out an assistance to move or pull out the parked own vehicle SV to a traffic lane. The double-parking mode is a mode which carries out an assistance to double park the own vehicle SV. The double-parking is a parking of parking the own vehicle SV perpendicular to the traveling direction of the traffic lane. The parallel-parking mode is a mode which carries out the assistance to parallel park the own vehicle SV. The parallel-parking is a parking of parking the own vehicle SV parallel to the traveling direction of the traffic lane. The double-parking mode and the parallel-parking mode do not directly relate to features of this embodiment. Thus, descriptions of the double-parking mode and the parallel-parking mode will be omitted.

For example, when the position of the shift lever is “P”, and the parking assist switch82is pressed once, the parking assist ECU10selects the pulling-out mode as the assist mode.

When the parking assist ECU10selects the pulling-out mode, the parking assist ECU10sets a target area in the pulling-out-permitted area. The target area is an area which the vehicle body200occupies when the own vehicle SV has been pulled out. Further, the parking assist ECU10sets, as a target position, the position of the own vehicle which is moved to the target area. The target position is a position where the center position of the own vehicle SV in the planar view is to reach. In this specification and the claims, moving the center position of the own vehicle SV to the target position or a predetermined position will be also referred to as “moving the own vehicle SV to the target position or the predetermined position”.

Then, the parking assist ECU10calculates a moving route for moving the own vehicle SV from its current position to the target position. The moving route is a route which can maintain the own vehicle SV spaced by a predetermined interval distance with respect to the objects such as other vehicles, curbstone, and guard rails while the center position of the own vehicle SV is moved from its current position to the target position. The moving route may be calculated by one of various known techniques (for example, a technique disclosed in JP 2015-3565 A).

Once the parking assist ECU10determines the moving route, the parking assist ECU10determines moving assist information used to move the own vehicle SV along the moving route. The moving assist information includes a moving direction of the own vehicle SV (in particular, the shift position of the transmission24), a steering angle pattern (steering angle information), and a moving speed pattern (moving speed information).

The parking assist ECU10sends shift control commands to the SBW ECU40via the CAN90, depending on the determined shift position. When the SBW ECU40receives the shift control commands from the parking assist ECU10, the SBW ECU40drives the SBW actuator42to change the shift position of the transmission24to a position commanded by the shift control commands. That is, the SBW ECU40executes a shift control.

The steering angle pattern is data on the steering angles associated with the center position of the own vehicle SV on the moving route. The steering angle pattern represents change of the steering angle or a target steering angle while the center position of the own vehicle SV is moved along the moving route. The parking assist ECU10sends steering commands (including the target steering angle) to the EPS ECU50via the CAN90in accordance with the determined steering angle pattern. When the EPS ECU50receives the steering commands from the parking assist ECU10, the EPS ECU50drives the assist motor51, based on the steering torque commanded by the steering commands to control the actual steering angle to the target steering angle. That is, the EPS ECU50executes a steering angle control.

The moving speed pattern is data on the moving speed associated with the center position of the own vehicle SV on the moving route. The moving speed pattern represents change of the moving speed or a target value of the moving speed while the center position of the own vehicle SV is moved along the moving route. The parking assist ECU10sends driving force control commands to the engine ECU20via the CAN90in accordance with the determined moving speed pattern. When the engine ECU20receives the driving force control commands from the parking assist ECU10, the engine ECU20controls the engine actuators22in response to the driving force control commands. That is, the engine ECU20executes a driving force control. Further, the parking assist ECU10sends braking force control commands to the brake ECU30via the CAN90in accordance with the determined moving speed pattern. When the brake ECU30receives the braking force control commands from the parking assist ECU10, the brake ECU30controls the brake actuators32in response to the braking force control commands. That is, the brake ECU30executes a braking force control.

As described below, the parking assist ECU10monitors the operation applied to the parking assist switch82, the shift position, and the surrounding situation around the own vehicle SV and determines whether a pulling-out assistance request is generated. Hereinafter, the pulling-out assistance request will be simply referred to as “assistance request”.

When conditions A1 to A4 below are all satisfied, the parking assist ECU10determines that the assistance request is generated.

Condition A1: The assistance request has not been generated.

Condition A2: The pulling-out mode is selected. That is, the shift position is the parking position “P”, and the parking assist switch82is pressed once.

Condition A3: The vehicle moving speed at a point of time when the condition A2 becomes satisfied, is a predetermined stop determination vehicle moving speed (for example, zero [km/h]).

Condition 4: An area (i.e., the pulling-out-permitted area) on the traffic lane next to an area where the own vehicle SV has been parked and which has a size and a shape which permit the own vehicle SV to exist, is detected.

When the assistance request is generated, the parking assist ECU10executes the parking assist control in the pulling-out mode.

In this embodiment, the parking assist ECU10changes the stopping number of stopping the own vehicle SV, depending on the surrounding situation around the own vehicle SV while the parking assist ECU10moves the own vehicle SV along the moving route. Below, a flow of specific processes will be described.

In an example shown inFIG.4, the own vehicle SV has been parked and thus the vehicle moving speed of the own vehicle SV is zero, and the shift position is the parking position “P”. There is a vehicle OB1to the left side of the own vehicle SV. Further, there is another vehicle OB2to the right side of the own vehicle SV.

The driver of the own vehicle SV presses the parking assist switch82once to move the own vehicle SV to the traffic lane RD. The parking assist ECU10detects the pulling-out-permitted area on the traffic lane RD. Since the conditions A1 to A4 are satisfied, the parking assist ECU10determines that the assistance request is generated.

The parking assist ECU10sets the target area Atgt in the pulling-out-permitted area. Then, the parking assist ECU10sets, as the target position Ptgt, the position of the own vehicle SV which is moved to the target area Atgt. Then, the parking assist ECU10calculates the moving route MP to move the own vehicle SV from its current position Po to the target position Ptgt.

Then, the parking assist ECU10determines whether there are the objects in a predetermined first area Rd1to the left side of the own vehicle SV on the two-dimension map. A length of the predetermined first area Rd1along the X axis and a length of the predetermined first area Rd1along the Y axis are sets such that the predetermined first area Rd1can accommodate a vehicle having an ordinary size. In this example, the parking assist ECU10detects the vehicle OB1in the predetermined first area Rd1. Hereinafter, the detected object (other vehicle) OB1in the predetermined first area Rd1will be referred to as “first object OB1”.

Further, the parking assist ECU10determines whether there are the objects in a predetermined second area Rd2to the right side of the own vehicle SV on the two-dimension map. A Length of the predetermined second area Rd2along the X axis and a length of the predetermined second area Rd2along the Y axis are sets similar to the predetermined first area Rd1. In this example, the parking assist ECU10detects a wall OB2in the predetermined second area Rd2. Hereinafter, the detected object (wall) OB2in the predetermined second area Rd2will be referred to as “second object OB2”.

Hereinafter, an end portion SVa of the own vehicle SV at the side of the traffic lane RD will be referred to as “vehicle end portion SVa”. Further, an end portion OB1aof the first object OB1at the side of the traffic lane RD will be referred to as “first end portion OB1a”. Furthermore, an end portion OB2aof the second object OB2at the side of the traffic lane RD will be referred to as “second end portion OB2a”.

Then, the parking assist ECU10calculates information on a positional relationship between the vehicle end portion SVa, the first end portion OB1a, and the second end portion OB2a. The parking assist ECU10changes or sets the stopping number, based on the calculated positional relationship.

In particular, as shown inFIG.5, the parking assist ECU10calculates a first distance d1, a second distance d2, and a third distance d3as the information on the positional relationship.

The first distance d1is a distance between the vehicle end portion SVa and the first end portion OB1ain a longitudinal direction of the own vehicle SV. As shown inFIG.5, when the first end portion OB1ais located at the side of the traffic lane RD with respect to the vehicle end portion SVa, the first distance d1calculated by the parking assist ECU10is a negative value. On the other hand, when the vehicle end portion SVa is located at the side of the traffic lane RD with respect to the first end portion OB1a, the first distance d1calculated by the parking assist ECU10is a positive value.

The second distance d2is a distance between the vehicle end portion SVa and the second end portion OB2ain the longitudinal direction of the own vehicle SV. As shown inFIG.5, when the second end portion OB2ais located at the side of the traffic lane RD with respect to the vehicle end portion SVa, the second distance d2calculated by the parking assist ECU10is a negative value. On the other hand, when the vehicle end portion SVa is located at the side of the traffic lane RD with respect to the second end portion OB2a, the second distance d2calculated by the parking assist ECU10is a positive value.

The third distance d3is a distance (≥0) between the first end portion OB1aand the second end portion OB2ain the longitudinal direction of the own vehicle SV.

Then, the parking assist ECU10determines whether the current situation (i.e., the situation at a point of time when an execution of the parking assist control is started) is a first situation or a second situation or a third situation. Hereinafter, this process will be also referred to as “situation determination process”. The first situation, the second situation, and the third situation will be described later in detail.

When the parking assist ECU10determines that the current situation is the first situation, the parking assist ECU10sets the stopping number to two. When the parking assist ECU10determines that the current situation is the second situation, the parking assist ECU10sets the stopping number to one. When the parking assist ECU10determines that the current situation is the third situation, the parking assist ECU10sets the stopping number to zero. That is, the parking assist ECU10does not stop the own vehicle SV.

Below, conditions of determining the first situation, the second situation, and the third situation will be described in detail.

As shown inFIG.6, when the own vehicle SV is at a position Po (the current position Po), the first object OB1interrupts a field of view from the own vehicle SV. The field of view from the own vehicle SV is a scope on the traffic lane RD which can be confirmed from the own vehicle SV. In this example, the field of view from the own vehicle SV is a scope on the traffic lane RD which the driver can see. As described later, the field of view from the own vehicle SV may be a scope on the traffic lane RD which the cameras72can take images.

When the field of view of the driver is interrupted by the first object OB1, the driver cannot confirm or see an object (a pedestrian) OB3which moves on the traffic lane RD and approaches the own vehicle SV from the left side of the own vehicle SV. Hereinafter, the object OB3will be referred to as “third object OB3”.

In addition, the second object OB2interrupts the field of view of the driver. Thus, the driver cannot confirm or see an object (a pedestrian) OB4which moves on the traffic lane RD and approaches the own vehicle SV from the right side of the own vehicle SV. Hereinafter, the object OB4will be referred to as “fourth object OB4”.

As shown inFIG.6, the own vehicle SV is moved along the moving route MP, and the first distance d1becomes equal to a predetermined positive distance ds (see a chain line SV′). The predetermined positive distance ds is set to a value that the field of view of the driver is not interrupted by the first object OB1. In this case, the driver can confirm the third object OB3.

In this example, there is a large difference between a position of the first end portion OB1ain the longitudinal direction of the own vehicle SV and a position of the second end portion OB2ain the longitudinal direction of the own vehicle SV. That is, the third distance d3is long. Thus, when the own vehicle SV is stopped at a point of time when the first distance d1becomes equal to the predetermined positive distance ds, the second object OB2still interrupts the field of view of the driver (i.e., the right field of view of the driver). Thus, at this time, it is difficult for the driver to confirm the fourth object OB4.

As shown inFIG.7, the own vehicle SV is further moved along the moving route MP, and the second distance d2becomes equal to the predetermined positive distance ds (see a chain line SV”). In this case, the driver can confirm the fourth object OB4. As described above, in the example shown inFIG.5, the driver can confirm the situation of the traffic lane RD with the own vehicle SV being stopped twice.

In consideration of the above, when conditions B1 to B3 are all satisfied, the parking assist ECU10determines that the current situation is the first condition.

Condition B1: The parking assist ECU10detects the first object OB1in the predetermined first area Rd1and detects the second object OB2in the predetermined second area Rd2.

Condition B2: The first distance d1is shorter than a predetermined first threshold dth1, and the second distance d2is shorter than the predetermined first threshold dth1. The condition B2 is a condition used to determine whether the first object OB1and the second object OB2both interrupt the field of view from the own vehicle SV (the field of view of the driver). The predetermined first threshold dth1is set, for example, to a value equal to or smaller than zero. The predetermined first threshold dth1may be changed, depending on types of vehicles. For example, when a length between a driver's seat and the vehicle end portion SVa is long, the predetermined first threshold dth1may be set to a positive value.

Condition B3: The third distance d3is longer than a predetermined positive second threshold dth2.

As understood from the above, the first situation includes a situation that the first object OB1and the second object OB2both interrupt the field of view of the driver, and the third distance d3is longer than the predetermined positive second threshold dth2.

When the parking assist ECU10determines that the current situation is the first situation, as shown inFIG.8, the parking assist ECU10sets a first stopping position Ps1and a second stopping position Ps2on the moving route MP. The first stopping position Ps1is a position at which the first distance d1becomes equal to the predetermined positive distance ds (seeFIG.6). The second stopping position Ps2is a position at which the second distance d2becomes equal to the predetermined positive distance ds (seeFIG.7). Then, the parking assist ECU10calculates the moving speed pattern which stops the own vehicle SV at the first stopping position Ps1and stops the own vehicle SV at the second stopping position Ps2.

FIG.9shows an example of the second situation. Also, in this example, there is the first object OB1to the left side of the own vehicle SV, and there is the second object OB2to the right side of the own vehicle SV. However, a distance between the first end portion OB1aand the traffic lane RD is slightly shorter than a distance between the second end portion OB2aand the traffic lane RD.

As shown, there is a small difference between the position of the first end portion OB1ain the longitudinal direction of the own vehicle SV and the position of the second end portion OB2ain the longitudinal direction of the own vehicle SV. That is, the third distance d3(not shown) is equal to or shorter than the predetermined positive second threshold dth2. In this situation, as shown inFIG.10, the own vehicle SV is moved along the moving route MP, and the first distance d1becomes equal to the predetermined positive distance ds. At this time, the field of view of the driver is not interrupted by the first object OB1and the second object OB2. Thus, the driver can confirm the third object OB3and the fourth object OB4. As described above, in an example shown inFIG.9, when the own vehicle SV is stopped once, the driver can confirm the situation of the traffic lane RD.

In consideration of the above, when conditions C1 to C3 are all satisfied, the parking assist ECU10determines that the current situation is the second situation.

Condition C1: The parking assist ECU10detects the first object OB1in the predetermined first area Rd1and detects the second object OB2in the predetermined second area Rd2.

Condition C2: The first distance d1is shorter than the predetermined first threshold dth1, and the second distance d2is shorter than the predetermined first threshold dth1.

Condition C3: The third distance d3is equal to or shorter than the predetermined positive second threshold dth2.

When the parking assist ECU10determines that the current situation is the second situation, the parking assist ECU10selects, as a target object, the object which has a shorter distance to the traffic lane RD, from the first object OB1and the second object OB2. In this example, the target object is the first object OB1. Then, the parking assist ECU10sets the first stopping position Ps1on the moving route MP. As shown inFIG.10, the first stopping position Ps1is a position at which the first distance d1between an end portion of the target object (i.e., the first end portion OB1a) and the vehicle end portion SVa becomes equal to the predetermined positive distance ds. Then, the parking assist ECU10calculates the moving speed pattern which stops the own vehicle SV at the first stopping position Ps1.

In another example shown inFIG.11, when the own vehicle SV is at a position Po (the current position Po), the second object OB2does not interrupt the field of view of the driver. Thus, the driver can confirm the fourth object OB4. Only the first object OB1interrupts the field of view of the driver. Also, in this situation, the driver can confirm the situation of the traffic lane RD with the own vehicle SV being stopped once.

In consideration of the above, when conditions D1 and D2 are both satisfied, the parking assist ECU10determines that the current situation is the second situation.

Condition D1: The parking assist ECU10detects the first object OB1in the predetermined first area Rd1and detects the second object OB2in the predetermined second area Rd2.

Condition D2: One of the first distance d1and the second distance d2is shorter than the predetermined first threshold dth1, and the remaining of the first distance d1and the second distance d2is equal to or longer than the predetermined first threshold dth1. The condition D2 is a condition used to determine whether only one of the first object OB1and the second object OB2interrupts the field of view of the driver.

Then, the parking assist ECU10sets the first stopping position Ps1on the moving route MP similar to the above. The first stopping position Ps1is a position at which the first distance d1becomes equal to the predetermined positive distance ds. Then, the parking assist ECU10calculates the moving speed pattern which stops the own vehicle SV at the first stopping position Ps1.

In further another example shown inFIG.12, there is only the first object OB1, and the first object OB1interrupts the field of view of the driver. Also, in this situation, the driver can confirm the situation of the traffic lane RD with the own vehicle SV being stopped once.

In consideration of the above, when conditions E1 and E2 are both satisfied, the parking assist ECU10determines that the current situation is the second situation. Then, the parking assist ECU10sets the first stopping position Ps1on the moving route MP. The first stopping position Ps1is a position at which the first distance d1becomes equal to the predetermined positive distance ds.

Condition E1: The parking assist ECU10detects the first object OB1in the predetermined first area Rd1but does not detect any objects in the predetermined second area Rd2.

Condition E2: The first distance d1is shorter than the predetermined first threshold dth1.

Further, when conditions F1 and F2 are both satisfied, the parking assist ECU10determines that the current situation is the second situation. Then, the parking assist ECU10sets the second stopping position Ps2on the moving route MP. The second stopping position Ps2is a position at which the second distance d2becomes equal to the predetermined positive distance ds.

Condition F1: The parking assist ECU10does not detect any objects in the predetermined first area Rd1but detects the second object OB2in the predetermined second area Rd2.

Condition F2: The second distance d2is shorter than the predetermined first threshold dth1.

As understood from the above, the second situation includes (i) a situation that the first object OB1and the second object OB2both interrupt the field of view of the driver, and the third distance d3is equal to or shorter than the predetermined positive second threshold dth2and (ii) only one of the first object OB1and the second object OB2interrupts the field of view of the driver.

When the current situation is not the first situation nor the second situation, the parking assist ECU10determines that the current situation is the third situation.

FIG.13shows an example of the third situation. In this example, there are the first object OB1and the second object OB2. However, the first distance d1and the second distance d2are both relatively large positive values. The first object OB1and the second object OB2do not interrupt the field of view of the driver. Thus, the driver can confirm the third object OB3and the fourth object OB4. In this situation, it is not necessary to provide the driver with chances to confirm the situation of the traffic lane RD. As understood from the above, the third situation includes a situation that the first object OB1and the second object OB2do not interrupt the field of view of the driver.

In the situation shown inFIG.13, the parking assist ECU10determines that the current situation is the third situation. Then, the parking assist ECU10calculates the moving speed pattern which does not stop the own vehicle SV.

FIG.14shows another example of the third situation. In this example, there are no objects in the predetermined first area Rd1and the predetermined second area Rd2. Thus, the driver can confirm the third object OB3and the fourth object OB4. Also, in the situation shown inFIG.14, the parking assist ECU10determines that the current situation is the third situation. Then, the parking assist ECU10calculates the moving speed pattern which does not stop the own vehicle SV.

When the parking assist ECU10stops the own vehicle SV at the first stopping position Ps1or the second stopping position Ps2, the parking assist ECU10suspends or temporarily stops the execution of the parking assist control. After the parking assist ECU10suspends the execution of the parking assist control, the parking assist ECU10executes an autonomous stopping process of maintaining the own vehicle SV stopped. The parking assist ECU10sends the braking force control command to the brake ECU30to generate the braking force to maintain the own vehicle SV stopped.

After the parking assist ECU10suspends the execution of the parking assist control and starts an execution of autonomous stopping process, the parking assist ECU10requests the driver to carry out a predetermined resuming operation. The resuming operation is an operation for resuming the execution of the parking assist control. In this embodiment, the resuming operation is an operation applied to the brake pedal31a.

In particular, as shown inFIG.15, the parking assist ECU10displays, in the third displaying area303of the assist mode screen image, a message1501which requests the driver to press the brake pedal31a. In addition, the parking assist ECU10outputs the message1501from the speaker83.

Then, the parking assist ECU10determines whether the brake pedal31ais pressed, based on the brake pedal operation amount BP. When the brake pedal31ais pressed, the parking assist ECU10requests the driver to release the brake pedal31a. In particular, as shown inFIG.16, the parking assist ECU10displays, in the third displaying area303of the assist mode screen image, a message1601which requests the driver to release the brake pedal31a. In addition, the parking assist ECU10outputs the message1601from the speaker83.

Then, the parking assist ECU10determines whether the brake pedal31ais released, based on the brake pedal operation amount BP. When the brake pedal31ais released, the parking assist ECU10stops the execution of the autonomous stopping process and resumes the execution of the parking assist control.

Next, a flow of the parking assist control in the pulling-out mode (hereinafter, will be also referred to as “pulling-out assistance”) will be described. The CPU10a(hereinafter, will be simply referred to as “CPU”) of the parking assist ECU10is configured or programmed to execute routines shown inFIGS.17to20, respectively each time a predetermined time (i.e., the first time) elapses.

In addition, the CPU is configured or programmed to execute routines not shown each time the first time elapses to acquire the vehicle surrounding information from the surrounding sensors70and update the two-dimension map, based on the vehicle surrounding information.

In addition, when a position of an ignition key switch or a start switch (not shown) of the own vehicle SV is changed from an OFF position to an ON position, the CPU executes an initializing routine (not shown) to set values of various flags (X1and X2) described below to zero, respectively.

At a predetermined timing, the CPU starts a process from a step1700of the routine shown inFIG.17and proceeds with the process to a step1701to determine whether a value of a first flag X1is “0”. When the value of the first flag X1is “0”, the first flag X1represents that the assistance request (i.e., the pulling-out assistance request) is not generated. On the other hand, when the value of the first flag X1is “1”, the first flag X1represents that the assistance request is generated. In other words, the CPU determines at the step1701whether the condition A1 is satisfied. When the value of the first flag X1is not “0”, the CPU determines “No” at the step1701and proceeds with the process directly to a step1795to terminate executing this routine once.

On the other hand, when the value of the first flag X1is “0”, the CPU determines “Yes” at the step1701and proceeds with the process to a step1702to determine whether the conditions A2 to A4 are satisfied. When at least one of the conditions A2 to A4 is not satisfied, the CPU determines “No” at the step1702and proceeds with the process directly to the step1795to terminate executing this routine once.

On the other hand, when the conditions A2 to A4 are satisfied, the CPU determines “Yes” at the step1702and proceeds with the process to a step1703to determine whether a predetermined start operation is carried out. The CPU displays, on the touch panel63, a first button used to select the moving direction of the own vehicle SV (i.e., a rightward direction or a leftward direction) and a second button used to start the pulling-out assistance. The predetermined start operation includes operations applied to the first button and the second button. When the predetermined start operation is not carried out, the CPU determines “No” at the step1703and proceeds with the process directly to the step1795to terminate executing this routine once.

On the other hand, when the predetermined start operation is carried out, the CPU determines “Yes” at the step1703and sequentially executes processes of steps1704to1708described below. Then, the CPU proceeds with the process to a step1709.

Step1704: The CPU changes the displaying mode of the screen image displayed on the touch panel63from the first mode to the second mode. Thereby, the assist mode screen image is displayed on the touch panel63.

Step1705: The CPU sets the target area Atgt in the pulling-out-permitted area. Then, the CPU sets, as the target position Ptgt, the center position of the own vehicle SV which is moved to the target area Atgt. Then, the CPU calculates the moving route MP along which the CPU moves the position of the own vehicle SV from its current position Po (a start position) to the target position Ptgt.

Step1706: The CPU determines the moving direction of the own vehicle SV (in particular, the shift position).

Step1707: The CPU calculates the steering angle pattern which moves the own vehicle SV along the moving route MP.

Step1708: The CPU executes the situation determination process as described above. The CPU determines which of the first situation, the second situation, and the third situation the current situation is, based on the vehicle surrounding information (in particular, the two-dimension map).

When the CPU proceeds with the process to the step1709, the CPU determines whether the current situation determined at the step1708is the first situation or the second situation. When the current situation is the first situation or the second situation, the CPU determines “Yes” at the step1709and sequentially executes processes of steps1710to1712described below. Then, the CPU proceeds with the process to the step1795to terminate executing this routine once.

Step1710: The CPU sets one or two stopping positions on the moving route MP, depending on the situation determined at the step1708. When the current situation is the first situation, the CPU sets the first stopping position Ps1and the second stopping position Ps2on the moving route MP as described above. When the current situation is the second situation, the CPU sets the first stopping position Ps1on the moving route MP as described above.

Step1711: The CPU calculates the moving speed pattern as described above.

Step1712: The CPU sets the value of the first flag X1to “1”.

Further, at a predetermined timing, the CPU starts a process from a step1800of the routine shown inFIG.18and proceeds with the process to a step1801to determine whether the value of the first flag X1is “1”, and a value of a second flag X2is “0”. When the value of the second flag X2is “0”, the second flag X2represents that the execution of the parking assist control is not suspended or not temporarily stopped. On the other hand, when the value of the second flag X2is “1”, the second flag X2represents that the execution of the parking assist control is suspended. When the value of the first flag X1is “0”, or the value of the second flag X2is “1”, the CPU determines “No” at the step1801and proceeds with the process directly to a step1895to terminate executing this routine once.

On the other hand, when the value of the first flag X1is “1”, and the value of the second flag X2is “0”, the CPU determines “Yes” at the step1801and proceeds with the process to a step1802to determine whether the situation determined at the step1708of the routine shown inFIG.17is the first situation or the second situation. When the situation determined at the step1708is the third situation, the CPU determines “No” at the step1802and proceeds with the process directly to a step1804to execute the parking assist control. In particular, the CPU sends the shift control commands to the SBW ECU40in accordance with the determined shift position to execute the shift control. Further, the CPU sends the steering commands including the target steering angle to the EPS ECU50in accordance with the determined steering angle pattern to execute the steering angle control. Furthermore, the CPU sends the driving force control commands to the engine ECU20in accordance with the moving speed pattern to execute the driving force control. Furthermore, the CPU sends the braking force control commands to the brake ECU30in accordance with the moving speed pattern to execute the braking force control. Thereby, the driver can move the center position of the own vehicle SV to the target position Ptgt on the traffic lane RD without carrying out driving operations to the shift lever, the steering wheel SW, the accelerator pedal21a, and the brake pedal31a. Then, the CPU proceeds with the process to the step1895to terminate executing this routine once.

It should be noted that when the driver requests the large braking force by operating the brake pedal31a, the CPU may control the brake actuators32to generate the braking force, depending on the driver's request. In this case, the CPU may set the driving force to zero by controlling the engine actuators22.

On the other hand, when the situation determined at the step1708is the first situation or the second situation, the CPU determines “Yes” at the step1802and proceeds with the process to a step1803to determine whether the own vehicle SV reaches the stopping position (the first stopping position Ps1or the second stopping position Ps2). When the own vehicle SV does not reach the stopping position, the CPU determines “No” at the step1803and proceeds with the process to the step1804to execute the parking assist control.

When the CPU repeatedly executes the routine shown inFIG.18, that is the CPU repeatedly executes the process of the step1804and the own vehicle SV reaches the stopping position, the CPU proceeds with the process to the step1803and determines “Yes” at the step1803and sequentially executes processes of steps1805and1806described below. Then, the CPU proceeds with the process to the step1895to terminate executing this routine once.

Step1805: The CPU executes the autonomous stopping process as described above.

Step1806: The CPU sets the value of the second flag X2to “1”. Thereby, the CPU determines “No” at the step1801and thus the execution of the parking assist control is suspended.

Further, at a predetermined timing, the CPU starts a process from a step1900of the routine shown inFIG.19and proceeds with the process to a step1901to determine whether the value of the second flag X2is “1”. When the value of the second flag X2is not “1”, the CPU determines “No” at the step1901and proceeds with the process directly to a step1995to terminate executing this routine once.

On the other hand, when the value of the second flag X2is set to “1” in the routine shown inFIG.18, and the execution of the parking assist control is suspended, the CPU determines “Yes” at the step1901and proceeds with the process to a step1902to request the resuming operation (i.e. the operation applied to the brake pedal31a). As shown inFIG.15, the CPU displays the message1501in the third displaying area303of the assist mode screen image and outputs the message1501from the speaker83.

Then, the CPU proceeds with the process to a step1903to determine whether the driver presses the brake pedal31a. When the driver presses the brake pedal31a, the CPU determines “Yes” at the step1903and proceeds with the process to a step1904to request the driver to release the brake pedal31a. As shown inFIG.16, the CPU displays the message1601in the third displaying area303of the assist mode screen image and outputs the message1601from the speaker83.

Then, the CPU proceeds with the process to a step1905to determine whether the brake pedal31ais released. When the brake pedal31ais not released, the CPU returns the process to the step1904.

On the other hand, when the brake pedal31ais released, the CPU determines “Yes” at the step1905and sequentially executes processes of steps1906and1907described below. Then, the CPU proceeds with the process to the step1995to terminate executing this routine once.

Step1906: The CPU stops the execution of the autonomous stopping process.

Step1907: The CPU sets the value of the second flag X2to “0”. Thereby, the CPU determines “Yes” at the step1801of the routine shown inFIG.18. Thus, the execution of the parking assist control is resumed.

When the driver does not press the brake pedal31aat a point of time when the CPU proceeds with the process to the step1903, the CPU determines “No” at the step1903and proceeds with the process to a step1908. The CPU determines whether a predetermined stopping condition or a predetermined cancelling condition is satisfied. The predetermined stopping condition becomes satisfied when an elapsing time Etm1since the process of the step1902is first executed, becomes equal to or longer than a predetermined first time threshold Tm1. When the predetermined stopping condition is not satisfied, the CPU determines “No” at the step1908and returns the process to the step1902.

When the predetermined stopping condition is satisfied, the CPU determines “Yes” at the step1908and sequentially executes processes of steps1909to1911described below. Then, the CPU proceeds with the process to the step1995to terminate executing this routine once.

Step1909: The CPU stops the execution of the autonomous stopping process.

Step1910: The CPU executes a predetermined termination process. In particular, the CPU displays, in the third displaying area303of the assist mode screen image, a message that the pulling-out assistance (i.e., the parking assist control in the pulling-out mode) is ended and outputs the message from the speaker83.

Step1911: The CPU sets the value of the first flag X1to “0” and sets the value of the second flag X2to “0”. As understood from the above, when the driver does not carry out the resuming operation, the execution of the parking assist control is terminated.

Further, at a predetermined timing, the CPU starts a process from a step2000of the routine shown inFIG.20and proceeds with the process to a step2001to determine whether the value of the first flag X1is “1”, and the value of the second flag X2is “0”. When the value of the first flag X1is “0”, or the value of the second flag X2is “1”, the CPU determines “No” at the step2001and proceeds with the process directly to a step2095to terminate executing this routine once.

On the other hand, when the value of the first flag X1is “1”, and the value of the second flag X2is “0”, the CPU determines “Yes” at the step2001and proceeds with the process to a step2002to determine whether the center position of the own vehicle SV reaches the target position Ptgt. When the center position of the own vehicle SV does not reach the target position Ptgt, the CPU determines “No” at the step2002and proceeds with the process directly to the step2095to terminate executing this routine once.

When the center position of the own vehicle SV reaches the target position Ptgt, the CPU determines “Yes” at the step2002and sequentially executes processes of steps2003and2004described below. Then, the CPU proceeds with the process to the step2095to terminate executing this routine once.

Step2003: The CPU executes the predetermined termination process. In particular, the CPU displays, in the third displaying area303of the assist mode screen image, a message representing that the pulling-out assistance is ended and outputs the message from the speaker83.

Step2004: The CPU sets the value of the first flag X1to “0”.

According to the configuration described above, the parking assist apparatus changes the stopping number of stopping the own vehicle SV while the parking assist apparatus moves the own vehicle SV along the moving route MP, depending on the surrounding situation around the own vehicle SV within a range of zero to two. Thus, the driver can be prevented from feeling bothersome, and the driver can be provided with chances to confirm the situation of the traffic lane RD.

When the current situation is the first situation, the parking assist apparatus stops the own vehicle SV twice. Further, the parking assist apparatus stops the own vehicle SV when the vehicle end portion SVa reaches a position forward from the first end portion OB1aby the predetermined positive distance ds and stops the own vehicle SV when the vehicle end portion SVa reaches a position forward from the second end portion OB2aby the predetermined positive distance ds. Thus, the driver can surely confirm the situation of the traffic lane RD.

When the current situation is the second situation, the parking assist apparatus stops the own vehicle SV once at a position at which the driver can confirm the objects (OB3and OB4) which approach the own vehicle SV from the left side and the right side of the own vehicle SV. Even when the own vehicle SV is stopped once, the driver can surely confirm the situation of the traffic lane RD. Thus, the driver can be prevented from feeling bothersome, and the driver can be provided with chances to confirm the situation of the traffic lane RD.

When the current situation is the third situation, the driver can surely confirm the situation of the traffic lane RD at a point of time when the execution of the parking assist control is started. Thus, the parking assist apparatus does not stop the own vehicle SV. Thus, the driver can be prevented from feeling bothersome.

It should be noted that the invention is not limited to the aforementioned embodiments, and various modifications can be employed within the scope of the invention.

Modified Example 1

In the embodiment described above, the CPU sets the stopping positions on the moving route MP before the execution of the parking assist control is started (the step1710), but the invention is not limited thereto. The CPU may be configured to set the first stopping position Ps1and the second stopping position Ps2, based on the vehicle surrounding information after the CPU starts the execution of the parking assist control.

Modified Example 2

The parking assist ECU10may be configured to set the stopping number and the stopping positions in consideration of the scope on the traffic lane RD which the cameras72(for example, the camera72a) can take images (hereinafter, will be referred to as “field-of-view scope of the cameras72”). In this case, the parking assist ECU10may be configured to request the driver to confirm the perspective image401and the moving direction image402of the assist mode screen image at a point of time when the parking assist ECU10stops the own vehicle SV at the stopping position (Ps1, Ps2). The predetermined positive distance ds may be set such that the field-of-view scope of the cameras72is not interrupted by the first object OB1or the second object OB2. With this configuration, the predetermined positive distance ds can be set to a smaller value, compared with when the driver confirms the situation of the traffic lane RD. Thus, safety can be improved.

Modified Example 3

The resuming operation is not limited to one described above and may be another operation. The resuming operation may be an operation applied to a switch provided near the steering wheel SW. Alternatively, the resuming operation may be an operation applied to a button displayed on the touch panel63. Alternatively, the resuming operation may be an operation applied to the parking assist switch82.

Modified Example 4

The parking assist control at least includes the steering angle control, the driving force control, and the braking force control. That is, the parking assist control may not include the shift control. When the parking assist control does not include the shift control, the CPU informs the driver of the shift position of the transmission24by the assist mode screen image on the touch panel63and/or the speaker83after the step1711of the routine shown inFIG.17. When the driver operates the shift lever and sets the shift position to the informed shift position, the CPU proceeds with the process to the step1712to set the value of the first flag X1to “1”.