JP2010208392A - Parking support device and parking support method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking support device and a parking support method capable of properly parking a vehicle at a right posture at a driver's intended position without depending on the initial position or vehicle posture when starting a parking support. <P>SOLUTION: A reference point O of an initial position and an initial posture Vo, and a reference point P of a target position and a parking posture Vp are found. When a turning posture Vr is decided, a crossing pint between a straight line OQ having an inclination of θn/2 relative to the initial posture Vo through the reference point O of the initial position, and a straight line PS having an inclination of θm/2 relative to the parking posture Vp through the reference point P of the target position are found from a posture angle θn of the turning posture Vr relative to the initial posture Vo, and a posture angle θm of the turning posture Vr relative to a parking posture Vp, so as to calculate a position, at which the crossing point is a reference point R, as a turning position. Then, a path connecting an arc C1' passing through the reference point O of the initial position and the reference point R of the turning position with an arc C2' passing through the reference point P of the target position and the reference point R of the turning position is calculated as a guide path. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a parking assistance device and a parking assistance method for calculating a guidance route including a turnback for parking a vehicle and assisting the vehicle to reach a target position along the guidance route.

  Conventionally, as a technique for assisting the parking operation of the vehicle, a technique for performing steering support and automatic steering control so that the vehicle travels forward and backward along a guidance route including turning back and reaches a target position is known. As a parking assistance apparatus employing this technology, a parking assistance system described in Non-Patent Document 1 below has been put into practical use.

  In the parking support system described in Non-Patent Document 1, the vehicle is stopped at a position that has a predetermined positional relationship with respect to a target position where the vehicle driver wants to park the vehicle, and the parking mode is selected and parked. When assistance is started, first, automatic steering control is performed so that the vehicle moves forward from the current position (initial position where parking assistance is started) along the predetermined guidance route and moves to the turning position. Then, after announcing that the shift gear is switched to reverse, automatic steering control is performed so that the vehicle moves from the turn-back position to the target position along a predetermined guidance route.

“Life Honda Smart Parking Assist System Owner's Manual”, [online], October 9, 2008, Honda Motor Co., Ltd., [March 9, 2009 search], Internet <URL: http: // www. honda.co.jp/manual/life/2009/pdf/2009-life-pa-all.pdf>

  However, the parking support system described in Non-Patent Document 1 is based on the premise that parking support is started at a position that has a predetermined positional relationship with respect to the target position, and the initial position and target position at which parking support is started. Since the guide route for guiding the vehicle to the target position is determined on the assumption that the relative positional relationship and the vehicle posture relationship are constant, the state deviated from the position and vehicle posture assumed by the system When parking assistance is started, there is a problem that the position and posture at the time of completion of parking differ from those intended.

  The present invention was devised to solve the above-described problems of the prior art, and is intended to guide a vehicle to a target position without depending on an initial position or a vehicle posture at which parking assistance is started. It is an object of the present invention to provide a parking assistance device and a parking assistance method that can appropriately calculate a guidance route including turnback and appropriately park a vehicle in a correct posture at a position intended by a driver.

  The present invention detects a reference point of an initial position at which parking assistance is started and a vehicle posture at the initial position, specifies a reference point of a target position for parking the vehicle and a vehicle posture at the target position, and the vehicle is moved to an initial position. When the vehicle posture at the turning position, which is the position where turning is performed in the process of moving from the target position to the target position, is determined, the angle between the vehicle posture at the initial position and the vehicle posture at the turning position is θn, and the vehicle posture at the target position A straight line having an inclination of θn / 2 with respect to the vehicle posture at the initial position through the reference point of the initial position and the reference point of the target position Then, an intersection point with a straight line having an inclination of θm / 2 with respect to the vehicle posture at the target position is obtained, and a position with this intersection point as a reference point is calculated as a turning position. Then, a route connecting the arc passing through the reference point of the initial position and the reference point of the turn-back position and the arc passing through the reference point of the target position and the reference point of the turn-back position via the return position from the initial position. It is calculated as a guide route for guiding to the target position.

  According to the present invention, the guide route including the turnback is calculated based on the positional relationship between the initial position where parking assistance is started and the target position of parking and the relationship of the vehicle posture. Even if parking support is started at this position and vehicle posture, it is possible to appropriately calculate a guidance route including a turnback for guiding the vehicle to the target position. Therefore, it is not necessary for the vehicle driver to accurately move the vehicle to a specific position in order to start parking assistance, and the vehicle is placed in a correct posture at the position intended by the driver with an extremely simple operation. It can be parked properly.

It is a block diagram which shows the basic composition of the parking assistance apparatus which concerns on this invention. It is a block diagram which shows the structure which added the route display part and the operation input part with respect to the basic composition of FIG. It is a block diagram which shows the structure which added the obstruction detection part with respect to the basic composition of FIG. It is a block diagram which shows the structure which added the angle range display part and the operation input part with respect to the basic composition of FIG. It is a block diagram which shows the structure which added the support information display part with respect to the basic structure of FIG. It is a block diagram which shows the structure which added the steering control part with respect to the basic composition of FIG. It is a block diagram which shows the structure which added the braking / driving control part to the structure of FIG. It is a figure explaining the calculation principle of the return position and guidance route by the parking assistance device concerning the present invention, and is a figure which illustrates the example of the relative relation between the initial position and initial posture, the target position, and the parking posture. It is a figure which divides and shows the range which a turning position can take by the combination of the steering direction of the vehicle before and after turning. It is a figure explaining the geometrical law regarding the attitude | position angle when a vehicle drive | works along a circular arc track. It is a figure explaining the calculation method of the turning position when a guidance path | route is considered as a combination of two circular arc tracks. It is a figure explaining the specific calculation method of a return position and a guidance route. It is a block diagram which shows the structure of the parking assistance system which is one Example of this invention. It is a flowchart which shows the operation | movement of the parking assistance by the parking assistance system which is one Example of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[Outline of the present invention]
First, an outline of the present invention will be described. The parking assistance device of the present invention calculates a route having only one turning point in the middle of the route as a guidance route for guiding the vehicle from the initial position where parking assistance is started to a target position which is a parking target. Thus, as shown in FIG. 1, as the functional configuration for calculating the guidance route, the initial position detection unit 1, the target position, and the target position are provided so that the vehicle moves along the calculated guidance route. It is basically provided with a specifying unit 2, a turning posture determining unit 3, a turning position calculating unit 4, and a guidance route calculating unit 5.

  The initial position detection unit 1 detects a reference point of an initial position (current position) at which parking assistance is started and a vehicle posture at the initial position (hereinafter referred to as an initial posture). The reference point for the initial position may be, for example, an intermediate point between two rear wheels at the current position of the vehicle at the time of starting parking assistance. Moreover, what is necessary is just to use the direction of the vehicle at the time of starting parking assistance as an initial posture as it is as an initial posture.

  The target position specifying unit 2 specifies a reference point of a target position that is a parking target and a vehicle posture at the target position (hereinafter referred to as a parking posture). The reference point of the target position and the parking posture are specified as relative positions and postures with respect to the initial position of the reference point and the initial posture. For example, detection of a white line indicating a parking frame using various sensor information such as an in-vehicle camera and a sonar Space that can be parked is detected by integration such as detection of a vehicle or a parked vehicle or a wall, and the reference point and vehicle posture when the vehicle is parked in the space may be specified in relation to the reference point and initial posture of the initial position. . In addition, information from an infrastructure facility that provides information on a vacant parking space may be acquired, and a reference point of a target position and a parking posture may be specified, or an image captured by an in-vehicle camera may be displayed. The reference position and the parking posture of the target position may be specified based on the position and direction designated by the vehicle driver in this image.

  The turn-back posture determination unit 3 determines a vehicle posture (hereinafter referred to as a turn-back posture) at a turn-back position, which is a position where turning is performed in the process in which the vehicle moves from the initial position to the target position. This turning posture is determined, for example, by specifying a posture angle θn relative to the initial posture. The determination of the turning posture may be a configuration in which the posture angle θn is automatically calculated internally, or an angle range in which the turning posture can be selected is presented to the vehicle driver, and the posture angle θn is determined from the angle selected within the range. May be calculated.

  The turn-back position calculation unit 4 uses an angle θn formed between the initial posture and the turn-back posture and an angle θm formed between the parking posture and the turn-back posture, and passes through the reference point of the initial position to θn / 2 with respect to the initial posture. An intersection point between a straight line having an inclination and a straight line having an inclination of θm / 2 with respect to the parking posture through a reference point of the target position is obtained, and a position with the intersection point as a reference point is calculated as a turning position. The specific method for calculating the cut-back position will be described later in detail.

  The guide route calculation unit 5 calculates, as a guide route, a route that connects an arc passing through the reference point of the initial position and the reference point of the return position and an arc passing through the reference point of the target position and the reference point of the return position. The specific method of calculating the guidance route will be described later in detail along with the method of calculating the return position.

  In the parking support device of the present invention, the turning position is specified by specifying the turning position, and the guidance route passing through the turning position is calculated. A route can be calculated. Therefore, as shown in FIG. 2, with respect to the basic configuration described above, a route display unit 6 that displays the guidance route calculated by the guidance route calculation unit 5, and an operation input unit 7 for the vehicle driver to perform an operation input. In this configuration, a plurality of guidance routes are displayed on this route display unit 6, and the guidance route selected by the vehicle driver using the operation input unit 7 is determined as the final guidance route. Is also possible. As the guidance route display unit 6, a monitor such as a liquid crystal display for navigation generally provided in a vehicle can be used. As the operation input unit 7, various operation input devices existing in the vehicle such as a joystick, an operation switch, and a touch panel can be used. In addition, voice guidance that prompts the vehicle driver to perform various operation inputs may be performed using an existing speaker in the vehicle.

  As shown in FIG. 3, if the obstacle detection unit 8 for detecting obstacles around the vehicle is added to the basic configuration described above, the guidance route calculated by the guidance route calculation unit 5 is When the vehicle driver interferes with an obstacle, the vehicle driver is informed of that fact, and the guidance route is repeatedly calculated while changing the turning posture until the guidance route for avoiding the obstacle is calculated. When the route to reach the target position cannot be calculated by turning back and forth, it is possible to notify the vehicle driver to that effect. The obstacle detection unit 8 may be configured to detect an object by performing image processing on an image captured by an in-vehicle camera, or to detect an object around the vehicle using a sonar sensor or the like. .

  In addition, as shown in FIG. 4, an angle range display unit 9 that displays an angle range in which a turning posture can be selected and an operation input unit 7 for a vehicle driver to perform an operation input with respect to the basic configuration described above. With the added configuration, the vehicle driver calculates the posture angle θn based on the angle selected using the operation input unit 7 within the angle range displayed on the angle range display unit 9, and determines the turning posture. Forms are also possible. As the angle range display unit 9, a monitor such as a liquid crystal display for navigation generally provided in a vehicle can be used as in the route display unit 6 shown in FIG.

  The parking assistance apparatus of the present invention performs parking assistance so that the vehicle reaches the target position along the guidance route calculated by the guidance route calculation unit 5. For example, as shown in FIG. 5, for the basic configuration described above, a figure that clearly indicates the current position of the vehicle, a frame figure that represents the target position and the turning position, information that indicates the handle angle at the initial position and the turning position, etc. As described above, the driving operation by the driver can be supported if the support information display unit 10 for displaying various types of support information useful for the vehicle driver performing the driving operation at the time of parking is added. As the support information display unit 10, a navigation liquid crystal display or the like generally provided in a vehicle is used, like the route display unit 6 shown in FIG. 2 or the angle range display unit 9 shown in FIG. A monitor can be used. Further, at this time, if voice guidance for guiding the steering direction or the like is performed by using the speaker already installed in the vehicle so that the vehicle moves along the guidance route, finer parking assistance can be performed.

  Further, as shown in FIG. 6, a steering control unit 11 for automatically controlling the steering of the vehicle so that the vehicle moves along the guidance route calculated by the guidance route calculation unit 5 is added to the basic configuration described above. With this configuration, the driver's operation burden during the parking operation can be further reduced by the automatic steering control by the steering control unit 11. Further, as shown in FIG. 7, if the braking / driving control unit 12 for controlling braking and driving of the vehicle is added to the configuration of FIG. 6, the vehicle is moved automatically along the guidance route. Thus, the vehicle can be parked at the target position, and the operation burden on the driver can be further reduced.

[Principle of calculation of cut-back position and guide route]
Next, a specific method for calculating the turn-back position and the guide route will be described in more detail with reference to an example in which a route drawn as a combination of two arcs in contact with each other at the turn-back position is obtained as a guide route.

  First, information on the position coordinates and initial posture Vo of the reference point O at the initial position, and information on the position coordinates and parking posture Vp of the reference point P at the target position are acquired. Here, it is assumed that the relative relationship between the reference point P of the target position and the parking posture Vp with respect to the reference point O and the initial posture Vo of the initial position is as shown in FIG. In FIG. 8, C1 is the minimum turning circle when the vehicle turns rightward from the initial position, and C2 is the minimum turning circle when the vehicle turns leftward from the target position. Here, it is necessary to calculate a guidance route including a turn using an arc trajectory that the distance between the centers of the minimum turning circle C1 and the minimum turning circle C2 is at least twice the radius of the minimum turning circles C1 and C2. Since it is a condition, if such a condition is not satisfied, the user is prompted to reset the initial position or the target position.

  Next, the turning posture Vr is determined. As described above, the switching posture Vr is determined by designating a relative posture angle θn with respect to the initial posture Vo. Here, since the angle range of the turning posture Vr is a range α (see FIG. 8) between two common tangents that are in contact with both the minimum turning circle C1 and the minimum turning circle C2, the turning posture Vr is within this range α. Θn is specified so that That is, when θn is automatically calculated internally, θn is calculated so that the turning posture Vr falls within the range α in FIG. Further, when the vehicle driver has an interface that allows the vehicle driver to designate the turning posture Vr, the turning posture is set so that the turning position is set in any of the regions A to C shown in FIG. The angle range α of Vr is presented to the driver by display or the like, and the turning posture Vr is selected within the range. FIG. 9A shows a possible range of the turning position when the vector of the initial posture Vo has no intersection with the minimum turning circle C2, and FIG. 9B shows the range of the minimum turning of the vector of the initial posture Vo. The range that the turn-back position can take when it has an intersection with the circle C2 is shown. Regions A to C in the figure are obtained by dividing the range where the turning position can be taken by the combination of the steering directions of the vehicle before and after turning, and when the turning position is set in the region A, After turning forward and reaching the turn-back position, it shows that the vehicle turns backward from the turn-back position and reaches the target position. When the turn-back position is set in the area B in the figure, the initial position After turning forward to the right and turning to the turn-back position from the turn-back position, the vehicle turns backward by turning right and reaches the target position. After reaching the turning position by turning left from the position, the target position is reached by turning left from the turning position.

  As described above, when the turning posture Vr is determined by designating the relative posture angle θn with respect to the initial posture Vo, the basic route calculated using the arc for setting the vehicle to the desired posture angle is enlarged similarly. By doing so, the guide route can be calculated. Hereinafter, the calculation method will be described with reference to FIGS.

FIG. 10 is a diagram showing a point R at which a posture angle with respect to the initial posture Vo becomes a desired posture angle θ on an arc orbit having a radius r passing through the reference point O at the initial position. As shown in FIG. 10, when the lateral direction of the initial position is the X axis and the straight traveling direction (the direction of the initial posture Vo) is the Y axis, the angle (stroke angle) φ formed by the Y axis and the straight line OR And the posture angle θ have the following relationship.
θ = 2φ

Using this geometrical principle, a series of guide paths from the initial position to the target position via the turning position, as shown in FIG. 11, the circular arc trajectory from the reference point O at the initial position to the reference point R at the turning position. Considering the combination of the path L1 and the path of the circular arc trajectory L2 from the reference point R of the turning position to the reference point P of the target position, the reference point R of the turning position is the position of the contact point of the two arcs L1 and L2. Become. Further, the relationship between the relative angle θop of the parking posture Vp with respect to the initial posture Vo, the angle θn formed by the initial posture Vo and the turning posture Vr, and the angle θm formed by the parking posture Vp and the turning posture Vr can be expressed by the following equations.
θop = θn + θm
Therefore, by defining the angle θn formed between the initial posture Vo and the turning posture Vr to a certain value, the angle θm formed between the parking posture Vp and the turning posture Vr is uniquely determined.

  Next, it is considered to obtain a specific arc path based on the above principle. First, as shown in FIG. 12, when the vehicle travels along the trajectory on the minimum turning circle C1 with the reference point O at the initial position as a starting point, the point Q at which the attitude angle becomes θn and the reference point P at the target position And a point S at which the attitude angle becomes θm when the vehicle travels along the trajectory on the minimum turning circle C2. Here, it can be seen from the geometric principle shown in FIG. 10 that the line segment OQ passes through the reference point O at the initial position and is a straight line having a stroke angle φ1 having an inclination of θn / 2 with respect to the initial posture Vo. . Further, it can be seen from the same principle that the line segment PS is a straight line having a stroke angle φ2 having a slope of θm / 2 with respect to the parking posture Vp through the reference point P of the target position. Then, when the intersection point where the extension line of the line segment OQ and the extension line of the line segment PS intersect is obtained, this intersection point becomes the reference point R of the turning position.

  Next, the ratio of the length of the line segment OQ to the length of the line segment OR is α1, the ratio of the length of the line segment PS to the length of the line segment PR is α2, and the arc C1 is defined as α1 with the reference point O at the initial position as a base point. When the arc C1 ′ enlarged twice and the arc C2 ′ enlarged similarly α2 times with reference to the reference point P of the target position as the arc C2 is drawn, the arc C1 ′ and the arc C2 ′ touch each other at the point R. Become. That is, the arc C1 ′ becomes the arc trajectory L1 from the reference point O at the initial position to the reference point R at the turn-back position, and the arc C2 ′ becomes the arc trajectory L2 from the reference point R at the turn-back position to the reference point P at the target position. . Therefore, a route combining these arcs is calculated as a series of guidance routes from the initial position to the target position via the turn-back position.

  As described above, if the attitude angle θop of the parking attitude Vp relative to the initial attitude Vo of the vehicle and the attitude angle θn of the return attitude Vr relative to the initial attitude Vo are determined, the return position can be uniquely identified. A combination of the path of the arc trajectory L1 from the initial position to the turn-back position and the path of the arc trajectory L2 from the turn-back position to the target position can be calculated as a guide path. Further, by selecting the turning posture Vr within the range of the angle range α shown in FIG. 8, the turning position can be selected as an arbitrary position, and at the same time, the target position passes from the initial position via the turning position. A guidance route to the position is also obtained.

  As described above, if the principle of the present invention is used, it is possible to appropriately calculate a guide route from an arbitrary initial position to an arbitrary target position by a combination of arcs by combining arcs. The turning position at which the vehicle turns is uniquely determined by specifying the posture angle θn. The method of determining the posture angle θn is calculated from the turning posture Vr by allowing the vehicle driver to select a desired turning posture Vr. Alternatively, the vehicle driver can select a desired turning position and calculate from the turning position.

  Further, an obstacle around the vehicle may be detected by various sensors such as an image obtained by an in-vehicle camera and sonar, and a guidance route to the target position may be automatically calculated without interfering with the obstacle. If there is no obstacle and the guide route selection range has a margin, the turning posture Vr is set to an intermediate position between the initial posture Vo and the parking posture Vr so that the circular arc tracks L1 and L2 have a gentle curve combination. In other words, the guide route may be calculated by setting the posture to θn = θm = θop / 2.

  Further, in the above description, a case is shown in which the vehicle travels forward by right steering and reaches a turn-back position, and then travels backward by left steering and obtains a guide route for the trajectory to reach the target position. As shown in Fig. 6, the trajectory guidance route drawn by the combination of the right turning angle and the trajectory guidance route drawn by the combination of the left turning angle can be appropriately calculated based on the same principle. In the above description, the target position is set on the left side of the vehicle with respect to the initial position. However, when the target position is set on the right side of the vehicle with respect to the initial position, the target position is set. It can be applied simply by reversing the rudder angle direction. Moreover, although the case where a vehicle is parked in parallel was illustrated in the above description, if the same principle is applied, it is applicable also to parallel parking.

  Furthermore, in the above description, the case where the route drawn as a combination of the circular arc trajectories L1 and L2 is obtained as a guide route on the assumption that the initial position is relatively close to the target position is illustrated. If the position and the target position are relatively distant from each other, a route obtained by adding a straight line to the circular arc track L1 or the circular arc track L2 may be obtained as the guide route. In this case, for example, a reference point of the vehicle position advanced by a predetermined distance from the initial position along the initial posture Vo is virtually considered as the reference point O of the initial position, and the arc trajectory L1 is obtained. On the other hand, a straight line connecting the reference point of the virtual initial position and the reference point of the actual initial position is added, or the reference point of the vehicle position advanced by a predetermined distance along the parking posture Vp from the target position is virtually The arc trajectory L2 is obtained by considering the reference point P at the initial position, and a straight line connecting the virtual parking position reference point and the actual parking position reference point is added to the arc trajectory L2. Just do it. If the guidance route is obtained by such a method, even if the initial position and the target position are in a relatively distant positional relationship, a route drawn only by the combination of the arc trajectories L1 and L2 is obtained as the guidance route. In addition, it is possible to suppress the spread of the guidance route, and it is possible to cope with a case where there is a restriction on a space in which the vehicle can move. In addition, when the guide route is obtained by the above method, the steering angle becomes discontinuous at the connection point between the circular arc tracks L1 and L2 and the linear track connected thereto, but this discontinuity makes smooth parking operation. If there is a concern about hindering, a route that smoothly connects the steering angles at points where the steering angles become discontinuous may be inserted.

[Example]
Next, specific examples of the present invention will be described.

  FIG. 13 is a block diagram illustrating a configuration of a parking assistance system 100 according to an embodiment of the present invention. The parking support system 100 has a function of automatically controlling vehicle movement along the guidance route, and various processes for calculating the guidance route and moving the vehicle are centrally controlled by the parking assistance ECU 110. It has a configuration.

  The parking assist ECU 110 includes a CPU, a ROM, a RAM, an input / output circuit, a power supply circuit, and the like, and includes an image / signal processing unit 111 that processes images and sensor signals, a route calculation unit 112 that performs route calculation, and automatic driving. A braking / driving control unit 113 and a steering control unit 114 that perform control for the purpose are provided. Here, an example in which each of these constituent units 111 to 114 is configured by common hardware and software as a functional configuration inside the parking assist ECU 110 is illustrated, but each of these functional units 111 to 114 is an individual hardware unit. Each of which may be comprised of hardware and software.

  Parking assist ECU 110 is connected to brake ECU 120, shift gear actuator 132 that drives shift gear 132, engine ECU 140, and steering actuator 151 that drives steering 152. A brake actuator 121 that drives the brake 122 is connected to the brake ECU 120.

  Signals from the wheel speed sensor 101 and the acceleration sensor 102 are input to the parking assist ECU 110 via the brake ECU 120. Further, the parking assist ECU 110 detects the signal of the shift sensor 103, the image of the in-vehicle camera 104, the signal of the sonar sensor 108, the information of the external infrastructure 109 that provides information such as the empty space of the parking lot, and the steering amount of the steering 152. A signal from the rotary encoder 153 is input. Further, the parking support ECU 110 is connected to a user interface such as an operation input device 105 for a vehicle occupant to input an operation, a monitor 106 for displaying various types of information, and a speaker 107 for outputting various types of information as audio.

  The image / signal processing unit 111 performs signal processing using one or more kinds of information such as an image taken by the in-vehicle camera 104, information from the sonar sensor 108 and the external infrastructure 109, and input information from the operation input device 105, Recognize the environment around the vehicle, such as detecting the initial position, initial posture, target position, parking posture, and obstacles for starting parking assistance.

  The route calculation unit 112 uses the information such as the coordinates and initial posture of the reference point of the initial position detected by the image / signal processing unit 111, the coordinates and parking posture of the reference point of the target position, the presence / absence of an obstacle, etc. A series of reaching the target position from the initial position via the turn-back position while performing information display on the monitor 106, outputting sound from the speaker 107, receiving input from the operation input device 105, etc. as needed according to the calculation logic. The guidance route is calculated.

  The route calculation unit 112 performs dead reckoning using sensor signals from the rotary encoder 153, the wheel speed sensor 101, the acceleration sensor 102, and the like, and estimates the position / posture of the vehicle moving along the guidance route as needed. The position / orientation estimation by the route calculation unit 112 may be performed using an image taken by the in-vehicle camera 104.

  The braking / driving control unit 113 is configured to move the vehicle at an optimum speed along the guidance route based on the guidance route and dead reckoning result calculated by the route calculation unit 112 and the sensor signal from the wheel speed sensor 101. When the accelerator opening degree is commanded to the engine ECU 140 and the vehicle approaches the turn-back position or the target position, or when the sonar sensor 108 detects an obstacle, the brake ECU 120 is given a braking command to automatically perform the braking control. . Further, the braking / driving control unit 113 controls the shift gear actuator 131 at a point where a shift change is necessary to automatically switch the shift gear 132 to a desired gear position.

  The steering control unit 114 moves the vehicle along the guidance route based on the result of the guidance route and dead reckoning calculated by the route calculation unit 112 and the current steering amount of the steering 152 detected by the rotary encoder 153. Is calculated to control the steering actuator 151. In a vehicle equipped with a power steering device, steering control linked to the control of the power steering device may be performed.

  FIG. 14 is a flowchart showing an operation of parking support by the parking support system 100 configured as described above. The parking assistance operation flow shown in FIG. 14 is started when the vehicle driver inputs an instruction to start parking assistance using the operation input device 105, and the parking assistance is performed unless an instruction to cancel the parking assistance operation is input. Continue until the operation is complete.

  When a parking driver start instruction is input by the vehicle driver, first, in step S101, the coordinates and initial posture of the reference point of the initial position (current position) are detected, and in step S102, the reference point of the target position for parking. The coordinates and the parking posture are specified as a relative position and posture with respect to the initial position. In step S103, it is determined whether or not parking is possible with one turn from the initial position to the parking position. Here, when parking is impossible by one turn from the initial position to the parking position, the vehicle is moved with respect to the vehicle driver by displaying information on the monitor 106 and outputting sound from the speaker 107 in step S104. Give instructions to do so. And it repeats the process of step S101-step S103 until the positional relationship of an initial position and a target position becomes the positional relationship which can be parked by one turn, and determines that it can park by one turn from the initial position to the parking position. If so, the process proceeds to step S105.

  Next, in step S105, an angle range that can be selected as the turning posture is presented to the vehicle driver from the relationship between the initial posture and the parking posture by display on the monitor 106 or the like. In step S106, it is determined whether the angle of the turning posture is selected by the vehicle driver from the angle range displayed on the monitor 106. If the desired angle is selected by the vehicle driver, the initial posture of the angle is selected. The relative angle with respect to is set to the posture angle θn of the turning posture, and the process proceeds to step S108. On the other hand, if the angle is not selected by the vehicle driver, in step S107, an arbitrary angle is selected within the above angle range to obtain the posture angle θn of the turning posture, and the process proceeds to step S108.

  Next, in step S108, the turning position is calculated based on the posture angle of the parking posture with respect to the initial posture and the posture angle θn of the turning posture obtained in step S106 or step S107. Specifically, by subtracting θn from an angle θop formed by the initial posture and the parking posture, an angle θm formed by the parking posture and the turning posture is obtained. An intersection of a straight line having an inclination of θn / 2 with respect to the initial posture through the reference point of the initial position and a straight line having an inclination of θm / 2 with respect to the parking posture through the reference point of the target position is obtained. Then, a position with this intersection point as a reference point is calculated as a turning position.

  Next, in step S109, the vehicle is guided from the initial position to the target position via the return position based on the initial position, target position, and return position reference points obtained in steps S101, S102, and S108, respectively. To calculate the guidance route. Specifically, the path of the circular arc trajectory L1 passing through the reference point of the initial position and the reference point of the turning position, and the path of the arc trajectory L2 passing through the reference point of the target position and the reference point of the turning position are obtained. A series of paths connecting the path of the circular arc path L1 and the path of the circular arc path L2 is calculated as a guidance path.

  Next, in step S110, the guide route calculated in step S109 is displayed on the monitor 106. In step S111, it is confirmed whether or not the guide route displayed on the monitor 106 is confirmed as the final guide route. Here, in order to allow the vehicle driver to change the guidance route as appropriate, an operation input of the vehicle driver that resets the angle of the turning posture is accepted (step S112), and the operation of resetting the angle of the turning posture is reset. When an input has been made (YES in step S112), the process returns to step S108 to newly calculate the return position and the guidance route, and display the newly calculated guidance route on the monitor 106. Then, when the guide route displayed on the monitor 106 is determined as the final guide route, the process proceeds to step S113.

  Next, in step S113, automatic control (path following control) of the vehicle is performed so that the vehicle moves from the initial position to the turn-back position along the guidance route determined in step S111. The path following control in step S113 is continued until it is determined in step S114 that the vehicle has reached the turning position. In the route follow-up control in step S113, the vehicle position and posture are always dead-reckoned and the result is fed back, and the steering is performed so that the difference between the guidance route determined in step S111 and the actual vehicle movement route is minimized. The actuator 151 and the like are controlled. When approaching the turning position, the engine ECU 140 is given a command to decrease the accelerator opening and the brake ECU 120 is given a braking command to stop the vehicle at the turning position. In addition, even when an obstacle that may come into contact with the vehicle is detected based on information from the in-vehicle camera 104, the sonar sensor 108, or the like during the path following control, the engine ECU 140 is instructed to decrease the accelerator opening. And a brake command to the brake ECU 120 to stop the vehicle. Further, when the vehicle is stopped at the turning-back position, the shift gear actuator 131 is driven and controlled so that the gear position of the shift gear 132 is switched so that the traveling direction of the vehicle is reversed.

  If it is determined in step S114 that the vehicle has reached the turning position, then in step S115, based on the result of dead reckoning, the turning position and turning posture in the guide route determined in step S111, the actual vehicle position and It is determined whether or not an error between the vehicle posture is a predetermined value or more. If the error is greater than or equal to the predetermined value, the route from the actual vehicle position to the target position is recalculated in step S116, and the vehicle is moved along the route recalculated in step S116 in step S117. The vehicle is automatically controlled (path following control) so as to move to the position. On the other hand, if the error is less than the predetermined value, in step S117, automatic control of the vehicle (route following control) is performed so that the vehicle moves to the target position along the guidance route calculated in step S111. The route following control in step S117 is continued until it is determined in step S118 that the vehicle has reached the target position. In the route follow-up control in step S117, as in the route follow-up control in step S113, the vehicle position and posture are always dead-reckoned and the result is fed back, and the guidance route determined in step S111 or recalculated in step S116. The steering actuator 151 and the like are controlled so that the difference between the route and the actual vehicle movement route is minimized. When the vehicle approaches the target position, the engine ECU 140 is given a command to decrease the accelerator opening, and the brake ECU 120 is given a braking command to stop the vehicle at the target position. In addition, even when an obstacle that may come into contact with the vehicle is detected based on information from the in-vehicle camera 104, the sonar sensor 108, or the like during the path following control, the engine ECU 140 is instructed to decrease the accelerator opening. And a brake command to the brake ECU 120 to stop the vehicle. When the vehicle is stopped at the target position, the shift gear actuator 131 is driven and controlled, and the gear position of the shift gear 132 is switched to the parking range.

  If it is determined in step S118 that the vehicle has reached the target position, in step S119, the vehicle driver is informed that parking support has been completed by displaying information on the monitor 106 or outputting sound from the speaker 107, and a series of parking operations are performed. End the support action.

  The parking support system 100 of the present embodiment described above is configured to automatically control the movement of the vehicle along the guidance route. However, as described above, the present invention supports various types of support for supporting the driving operation of the vehicle driver. The present invention can also be effectively applied to a parking assistance system configured to provide parking assistance by presenting information. In this case, since the route calculated as the guide route is a combination of arcs, for example, the handle angle at the initial position, the turning position, and the steering angle from the turning position to the target position are specified by voice guidance, monitor display, etc. Then, if the vehicle driver is operated by the steering wheel, the brake, and the shift, the vehicle can be moved along the guidance route to reach the target position. Also, as described above, when a route in which a straight line is added to the arc is calculated as the guidance route, the vehicle driver is notified of the point where the path of the guidance route switches from the straight line to the arc, and the steering wheel angle is designated each time. It is desirable.

[effect]
As described above in detail with reference to specific examples, according to the parking assistance device of the present embodiment, based on the positional relationship between the initial position where parking assistance is started and the parking target position and the vehicle posture relationship. Therefore, even if parking support is started at an arbitrary position and vehicle posture with respect to the target position, a guidance path including a return for guiding the vehicle to the target position is calculated. Can be calculated appropriately. Therefore, it is not necessary for the vehicle driver to accurately move the vehicle to a specific position in order to start parking assistance, and the vehicle is placed in a correct posture at the position intended by the driver with an extremely simple operation. It can be parked properly.

  That is, in the prior art, the initial position and initial posture for starting parking assistance are predetermined in relation to the target position and the parking posture, and the vehicle driver must adjust the initial position and initial posture, It is complicated. In addition, since the position and posture accuracy after parking is dependent on how accurate the position and posture are started by the driving operation of the driver, the initial position and posture are assumed by the system. If it deviates from, parking cannot be completed at a desired position and posture. Therefore, it is necessary for the vehicle driver to adjust the position and posture after the parking is completed again, and the operation of the vehicle driver is further complicated. In addition, since the vehicle is guided along a predetermined route calculated in advance, there is a problem that it is not possible to deal with a narrow parking lot or an obstacle on the route. On the other hand, according to the parking assistance device of the present embodiment, since the parking assistance can be started at an arbitrary position and posture, the vehicle driver needs to adjust the initial position and the initial posture for starting the parking assistance. In addition, since the position and posture accuracy after parking is not dependent on the driving operation of the vehicle driver at the start of parking assistance, the vehicle can be appropriately parked at a desired position and posture. In addition, even when there are obstacles on a narrow parking lot or route, it is possible to use the parking assistance because the restrictions such as the positional relationship with the surrounding parked vehicles can be relaxed by adjusting the route and turnover position. The scene can be expanded.

  In addition, according to the parking assistance device of the present embodiment, a plurality of routes that are candidates for the guidance route are calculated and presented to the vehicle driver, and the route selected by the driver among the plurality of routes is finally determined. By determining the guidance route and providing parking assistance along the guidance route, the driver's intention can be reflected to more appropriately support the parking operation of the vehicle.

  In addition, according to the parking assist device of the present embodiment, by detecting obstacles around the vehicle and automatically calculating a guide route that avoids the detected obstacles, appropriate parking assistance corresponding to the surrounding environment is provided. It can be implemented more effectively.

  Moreover, according to the parking assistance apparatus of the present embodiment, by presenting to the vehicle driver an angle range that can be selected as the turning posture, and determining the turning posture based on the angle selected by the driver within the range. The parking operation of the vehicle can be more appropriately supported by reflecting the driver's intention.

  Further, according to the parking assist device of the present embodiment, the initial position and the target position are in a positional relationship that is relatively separated by obtaining a route obtained by adding a straight line to the circular arc trajectory, and the vehicle moves. Even when there is a restriction on the space that can be used, it is possible to perform appropriate parking assistance corresponding to such an environment.

  The embodiment described above is an example of application of the present invention, and the technical scope of the present invention is not intended to be limited to the contents described in the above embodiment. That is, the technical scope of the present invention is not limited to the specific technical matters disclosed in the above embodiments, but includes various modifications, changes, alternative techniques, and the like that can be easily derived from this disclosure.

DESCRIPTION OF SYMBOLS 1 Initial position detection part 2 Target position specific | specification part 3 Switch-back attitude | position determination part 4 Switch-back position calculation part 5 Guidance path calculation part 6 Path | route display part 7 Operation input part 8 Obstacle detection part 9 Angle range display part 10 Support information display part 11 Steering Control unit 12 Braking / driving control unit 100 Parking support system 110 Parking support ECU
111 Image / Signal Processing Unit 112 Path Calculation Unit 113 Braking / Drive Control Unit 114 Steering Control Unit

Claims (9)

An initial position detecting means for detecting a reference point of an initial position for starting parking assistance and a vehicle posture at the initial position;
A target position specifying means for specifying a reference point of a target position for parking the vehicle and a vehicle posture at the target position;
A turning posture determining means for determining a vehicle posture at a turning position that is a position where turning is performed in a process in which the vehicle moves from the initial position to the target position;
When the angle between the vehicle posture at the initial position and the vehicle posture at the turn-back position is θn, and the angle between the vehicle posture at the target position and the vehicle posture at the turn-back position is an angle θm, the initial position A straight line having a slope of θn / 2 with respect to the vehicle posture at the initial position through the position reference point and a slope of θm / 2 with respect to the vehicle posture at the target position through the reference point of the target position A turning position calculating means for obtaining an intersection with a straight line having, and calculating a position with the intersection as a reference point as the turning position;
A path connecting the arc passing through the reference point of the initial position and the reference point of the turn-back position and the arc passing through the reference point of the target position and the reference point of the turn-back position, the vehicle from the initial position to the turn-back position And a guidance route calculation means for calculating as a guidance route for guiding the vehicle to the target position via a parking assistance device. Route presentation means for presenting the route calculated by the guidance route calculation means to the vehicle driver;
The guidance route calculation means calculates a plurality of routes that are candidates for the guidance route, causes the route presentation means to present the same to a vehicle driver, and selects a route selected by the vehicle driver from the plurality of routes as the guidance route. The parking support device according to claim 1, wherein the parking support device is determined. It further comprises obstacle detection means for detecting obstacles around the vehicle,
The parking assistance device according to claim 1, wherein the guidance route calculation unit calculates a guidance route that avoids the obstacle detected by the obstacle detection unit. An angle range presenting means for presenting a vehicle driver with a selectable angle range of the vehicle posture at the turning position;
The parking assistance device according to claim 1, wherein the turning posture determining means determines a vehicle posture at the turning position based on an angle selected by a vehicle driver within the angle range.   The guide route calculation means uses a position that is ahead in the straight direction of the vehicle as compared to the actual initial position as a virtual initial position, and is actually applied to an arc that passes through the reference point of the virtual initial position and the reference point of the turn-back position. 5. The parking assist device according to claim 1, wherein the guide route is calculated by adding a straight line connecting the initial position and the virtual initial position. 6.   The guide route calculation means uses a position that is ahead of the actual target position in the straight direction of the vehicle as a virtual target position, and actually calculates the reference point of the virtual target position and the arc passing through the reference point of the turn-back position. The parking assist device according to any one of claims 1 to 5, wherein the guide route is calculated by adding a straight line connecting the target position and the virtual target position.   The support information presenting means for presenting support information for assisting the movement of the vehicle along the guide route calculated by the guide route calculating means to a vehicle driver. The parking assistance device according to one item.   The steering control means for controlling the steering of the vehicle so that the vehicle moves along the guidance route calculated by the guidance route calculation means, further comprising a steering control means. Parking assistance device. Detecting a reference point of an initial position for starting parking assistance and a vehicle posture at the initial position;
Identifying a reference point of a target position for parking the vehicle and a vehicle posture at the target position;
Determining a vehicle posture at a turning position, which is a position where turning is performed in a process in which the vehicle moves from the initial position to the target position;
When the angle between the vehicle posture at the initial position and the vehicle posture at the turn-back position is θn, and the angle between the vehicle posture at the target position and the vehicle posture at the turn-back position is an angle θm, the initial position A straight line having a slope of θn / 2 with respect to the vehicle posture at the initial position through the position reference point and a slope of θm / 2 with respect to the vehicle posture at the target position through the reference point of the target position Obtaining an intersection with a straight line, and calculating a position with the intersection as a reference point as the turning position;
A path connecting the arc passing through the reference point of the initial position and the reference point of the turn-back position and the arc passing through the reference point of the target position and the reference point of the turn-back position, the vehicle from the initial position to the turn-back position And a step of calculating as a guide route for guiding to the target position via the vehicle.

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