JP2007331548A - Parking support device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking support device capable of highly precisely specifying a parking space fitted to the intention of a driver. <P>SOLUTION: This parking support device for supporting the parking is provided with an imaging means 20 capturing the image of a vehicle backward area, an obstacle information acquisition means 70 acquiring obstacle information around the vehicle in a process where the vehicle reaches a parking start position, and a parking space detecting means 41 detecting the parking space based on the obstacle information acquired by the obstacle detecting means; and is characterized in specifying the parking space intended by the driver based on the positional relation between the captured space captured by the imaging means and the parking space detected by the parking space detecting means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a parking assistance device that assists parking, and more particularly, to a parking assistance device that assists a user in setting a target parking position.

  2. Description of the Related Art Conventionally, an imaging unit that captures an outside of a vehicle and a display unit that displays a captured image are provided, and a target parking frame is displayed on a screen of the display unit to assist a parking operation performed by the driver of the vehicle. A parking assist device, which obtains a vehicle deflection angle calculated by a moving distance and a turning radius of the vehicle during a turning movement as a running state of the vehicle up to the parking preparation position, and based on this deflection angle, Estimating the target parking position with respect to the parking preparation position, calculating an initial setting position of the target parking frame based on the estimated target parking position, and displaying the target parking frame at the initial setting position. A characteristic parking assistance device is known (see, for example, Patent Document 1).

Further, a technique for detecting a parking space that may exist adjacent to a parked vehicle based on a distance data series (dot sequence) to the parked vehicle detected by a distance measuring means such as a laser radar is known (for example, , See Patent Document 2).
Japanese Patent No. 3729786 JP 2002-243857 A

  However, unlike the configuration described in Patent Document 2, the configuration described in Patent Document 1 is advantageous in terms of cost and the like because it does not use a distance measuring means such as a laser radar. The estimation accuracy of the intended parking space is inevitably limited.

  On the other hand, in the configuration described in Patent Document 2, the position of the parking space can be detected with relatively high accuracy by using the distance measuring unit, but a plurality of parking spaces can be detected as candidates. It is necessary to specify which parking space in the space is the parking space intended by the driver. If there is an error in such selection, there arises a disadvantage that parking assistance for a parking space not intended by the user is executed. For example, when there is an error in the selection, the target parking frame is intended by the driver on the screen when setting the target parking position based on the screen operation (touch panel operation) performed by the driver at the parking start position. Initially displayed in a parking space different from the parking space, the user must operate the touch switch to move the position of the target parking frame to the intended parking space position. There is a problem that it takes a great burden.

  Then, an object of this invention is to provide the parking assistance apparatus which can pinpoint the parking space matched with a driver | operator's intent accurately.

In order to achieve the above object, the first invention provides a parking assistance device for assisting parking in a target parking space.
Imaging means for imaging the vehicle rear area;
Obstacle information acquisition means for acquiring obstacle information around the vehicle in the process of the vehicle reaching the parking start position;
A parking space detecting means for detecting a parking space based on the obstacle information acquired by the obstacle detecting means;
A target parking space specifying means for specifying a target parking space from among the parking spaces detected by the parking space detecting means;
The target parking space specifying means specifies the target parking space based on a positional relationship between the parking space detected by the parking space detecting means and the imaging space imaged by the imaging means.

2nd invention is the parking assistance apparatus which concerns on 1st invention,
The target parking space specifying unit specifies, as a target parking space, a parking space existing in an imaging space captured by the imaging unit at a parking start position among parking spaces detected by the parking space detecting unit. It is characterized by that.

3rd invention is the parking assistance apparatus which concerns on 1st or 2nd invention,
Display means for displaying a vehicle rear image captured by the imaging means;
Display control means for superimposing and displaying a target parking frame that can be moved by the user on the vehicle rear image when the vehicle is present at the parking start position;
A target parking position determining means for determining a target parking position based on the position of the target parking frame on the vehicle rear image;
The display control means initially displays the target parking frame at a position corresponding to the target parking space specified by the target parking space specifying means on the vehicle rear image.

Moreover, in order to achieve the said objective, 4th invention is the parking assistance apparatus which assists the parking with respect to a target parking space,
In the parking support device that supports parking for the target parking space,
Imaging means for imaging the vehicle rear area;
Display means for displaying a vehicle rear image captured by the imaging means;
Display control means for superimposing and displaying a target parking frame that can be moved by the user on the vehicle rear image when the vehicle is present at the parking start position;
Obstacle information acquisition means for acquiring obstacle information around the vehicle in the process of reaching the parking start position;
Based on the obstacle information acquired by the obstacle detection means, a parking space detection means for detecting a parking space existing around the vehicle in the process of reaching the parking start position;
Parking space storage means for sequentially storing position information regarding the parking space detected by the parking space detection means;
The position information on the latest parking space stored in the storage means is read out, and it is determined whether the read out parking space exists in the imaging space imaged by the imaging means at the parking start position, and the reading is performed. If it is determined that the parking space does not exist in the imaging space, the next new parking space stored in the storage means is read, and whether or not the read parking space exists in the imaging space is determined. A target parking space specifying means for judging,
The display control means initially displays the target parking frame at a position corresponding to the parking space when the parking space existing in the imaging space is specified by the target parking space specifying means. .

5th invention is the parking assistance apparatus which concerns on 4th invention,
The parking space storage means is configured to store at least two parking spaces detected on the left and right sides of the vehicle separately from the left and right in order from the newest one,
The target parking space specifying means selects one of the left and right, and sequentially reads out the latest parking space on the selected side from the parking spaces stored in the parking space storage means, and performs the determination process. And

  ADVANTAGE OF THE INVENTION According to this invention, the parking assistance apparatus which can pinpoint the parking space matched with a driver | operator's intention with sufficient accuracy is obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a system configuration diagram showing an embodiment of a parking assistance apparatus 10 according to the present invention. As shown in FIG. 1, the parking assistance device 10 is configured around an electronic control unit 12 (hereinafter referred to as “parking assistance ECU 12”). Parking assistance ECU12 is comprised as a microcomputer which consists of CPU, ROM, RAM, etc. which were mutually connected via the bus | bath which is not shown in figure. The ROM stores programs and data executed by the CPU.

  The parking assist ECU 12 detects a steering angle sensor 16 that detects a steering angle of a steering wheel (not shown) and a vehicle speed via an appropriate bus such as a CAN (Controller Area Network) or a high-speed communication bus. A vehicle speed sensor 18 is connected. The vehicle speed sensor 18 may be a wheel speed sensor that is disposed on each wheel and generates a pulse signal at a cycle according to the wheel speed.

  A reverse shift switch 50 and a parking switch 52 are connected to the parking assist ECU 12. The reverse shift switch 50 outputs an ON signal when the shift lever is operated to the reverse position (reverse), and maintains the OFF state in other cases. Moreover, the parking switch 52 is provided in the vehicle interior and can be operated by the user. The parking switch 52 is normally maintained in an off state, and is turned on by a user operation.

  A back monitor camera 20 that captures a landscape in a predetermined angle area behind the vehicle is connected to the parking assist ECU 12. The back monitor camera 20 includes an image sensor such as a charge-coupled device (CCD) and a complementary metal oxide semiconductor (CMOS) and a wide-angle lens, and is attached to the rear portion of the vehicle. The attachment angle and the angle of view (viewing angle) of the back monitor camera 20 are appropriately determined so that the scenery behind the vehicle is imaged at a predetermined angle approximately symmetrically about the vehicle longitudinal axis.

  FIG. 2 shows an example of the angle of view of the back monitor camera 20. In the example shown in FIG. 2, the angle of view (imaging range) of the back monitor camera 20 is defined by a hatching area. The angle of view of the back monitor camera 20 is, for example, a home base type shape defined by a distance a from the rear wheel axis center of the vehicle to the rear along the vehicle longitudinal direction and a width b along the vehicle lateral direction. It may be. The distance a may be about 10 m, for example, and the width b may be about 20 m. Note that the shape and size of the angle of view of the back monitor camera 20 should be appropriately set according to the type of vehicle and the like, and the present invention is not limited to the above-described configuration.

  The parking assist ECU 12 is connected to a distance measuring sensor 70 that detects a distance from an obstacle using sound waves (for example, ultrasonic waves), radio waves (for example, millimeter waves), light waves (for example, laser), or the like. The distance measuring sensor 70 may be any sensor that can detect a distance, such as a laser vision, a millimeter wave radar, an ultrasonic radar, or a stereo vision. The distance measuring sensor 70 is set on both the left and right sides of the front portion of the vehicle.

  As shown in FIG. 3, the distance measuring sensor 70 emits a sound wave or the like in a predetermined direction centering on the vehicle width direction and receives the reflected wave during operation, so that the obstacle sensor located on the side of the vehicle Detect distance. The distance measuring sensor 70 is mounted, for example, near the bumper in the front part of the vehicle, and may emit a sound wave or the like toward a diagonally forward direction of 17 to 20 degrees with respect to the lateral direction of the vehicle.

  FIG. 4 is a schematic diagram showing a point sequence relating to the vehicle Z obtained when a vehicle (vehicle) including the distance measuring sensor 70 travels near the obstacle (vehicle Z) in FIG. As shown in FIG. 4, the distance measuring sensor 70 may output an obstacle reflecting portion (a set of reflection points such as sound waves) in a point sequence, and output data is stored in a memory 72 (for example, for each output cycle). EEPROM) may be stored at any time.

  The distance measuring operation by the distance measuring sensor 70 and the storage processing of the detection result (point sequence data) of the distance measuring sensor 70 are performed in a situation where the parking switch 52 is not turned on when a predetermined condition is satisfied. It is also desirable that it has been implemented. As a result, when the parking switch 52 is turned on, it is possible to detect a parking space that exists from that point in time to the vehicle position, as will be described later. The predetermined condition may be a case where the vehicle speed is equal to or lower than a predetermined value, a case where it is determined from the map data of the navigation device that the vehicle position is in the parking lot, and the like.

  FIG. 5 is a block diagram showing the main functions of the parking assist ECU 12 of this embodiment. The parking assist ECU 12 includes a parking space detection unit 41, an information output control unit 42, a deflection angle calculation unit 43, a parking space information storage unit 44, a parking space information generation unit 45, a target parking space identification unit 46, A target movement trajectory calculation unit 48 and a target parking position determination unit 49 are included. Hereinafter, the configuration and function of each unit will be described.

  The parking space detection unit 41 detects a parking space that may exist on the side of the vehicle based on the detection result (point sequence) of the distance measuring sensor 70. Based on the detection results of the left and right distance measuring sensors 70, the parking space detection unit 41 detects parking spaces that may exist on the left and right sides of the vehicle independently on the left and right sides in parallel. The left and right detection methods may be the same.

  The parking space detection method differs between garage parking and parallel parking. Below, an example of the detection method of the parking space in the case of garage parking is demonstrated. The parking switch 52 may include a switch for specifying either garage parking or parallel parking. In this case, the parking assist ECU 12 may select a parking mode (garage insertion mode or parallel mode) according to the designated parking mode. ).

  FIG. 6 is a plan view showing the situation of a parking lot for parking in a garage. In this situation, there are a plurality of parking spaces (indicated by dotted squares) on both sides of the vehicle, and obstacles adjacent to the parking space. (Vehicle Z) is parked. In FIG. 6, it is assumed that the vehicle (own vehicle) passes by the side of the obstacle (and the parking space adjacent to the obstacle) in the direction indicated by the arrow in the figure. In the following description, the back side and the near side are based on the traveling direction of the vehicle (own vehicle).

  Based on the detection result of the distance measuring sensor 70, the parking space detection unit 41 determines that the predetermined space is present when there is a space in which no point sequence is longer than the predetermined length L1 from the end point of the point sequence having a predetermined length (> 1 m). It is determined that there is a parking space in the space of length L1 or longer, and a parking space valid flag is set. The predetermined length L1 is a minimum opening width necessary as a parking space for garage parking, and is a value that should be determined depending on the vehicle width of the own vehicle (L1 = 2.5 m in this example). ).

  If it is assumed that the vehicle has traveled from position A0 to position A1 in the parking lot situation as shown in FIG. 6, the parking space detection unit 41 is a distance measurement sensor acquired while the vehicle travels from position A0 to position A1. Based on the point sequence data by 70, three parking spaces S1 to S3 are detected on the left side of the vehicle, and three parking spaces S4 to S6 are detected on the right side of the vehicle.

  The parking space detection unit 41 may detect the parking space in real time based on the detection result of the distance measuring sensor 70 that is input as needed, or the parking switch 52 is turned on at the parking start position, for example. The parking space (the parking space that existed in the process of reaching the parking start position) retroactively based on the stored data of the detection result by the distance measuring sensor 70 acquired within the predetermined travel distance before the parking start position. May be detected.

  When the parking space detection unit 41 detects the parking space (that is, when the parking space valid flag is set), the parking space information generation unit 45 generates information about the parking space (hereinafter referred to as “parking space information”). . The parking space information includes information related to the position of the parking space, and may include information related to the direction of the parking space. The position of the parking space is, for example, the coordinate value of a predetermined position in the parking space, more specifically, the coordinate value of the position of the center of the vehicle rear wheel axis in the parking space when it is assumed that the vehicle is guided into the parking space. It may correspond to. The position of the parking space may be grasped by a relative position with respect to the vehicle position.

  The position of the parking space may be determined based on the end position P (see FIG. 4) of the obstacle on the turning center side, and when the parking space is detected between the two obstacles ( For example, when there is a section without a point sequence longer than a predetermined length between the end points of the point sequence representing two obstacles), it is determined based on the intermediate point between the two end points of the two obstacles May be.

  The direction of the parking space may correspond to the front-rear axis direction of the vehicle in the parking space when it is assumed that the vehicle is guided into the parking space. The direction of the parking space may be determined on the basis of the direction of the vehicle around the point where the parking space is detected or its change mode, or the shape (approximation result) of the obstacle. When a parking space is detected between the two, it may be determined based on a straight line connecting the end points of two obstacles.

  Note that when the position of the parking space is grasped relative to the vehicle position, the position of the parking space changes as the vehicle subsequently travels. For this reason, when the parking space information generation unit 45 grasps the position of one parking space with respect to a certain vehicle position (hereinafter referred to as “reference vehicle position”), the parking start position is determined from the subsequent reference vehicle position. The driving state of the vehicle until is monitored and the change in the position of the parking space is tracked. That is, the parking space information generation unit 45 updates the position information of the parking space.

  For example, the parking space information generation unit 45 uses the following formulas (1) to (3), for example, to determine the positional relationship between the reference vehicle position and the current vehicle position (and thus the position of the parking space and the current vehicle position). ) May be estimated.

各式において、θ、及び、Ｘ，Ｙは、車両の後輪軸中心を原点して、車幅方向をＸ軸、車両前後方向をＺ軸とする２次元座標系で定義され、Ｘ_０，Ｙ_０は、基準車両位置での車両の後輪軸中心の座標値である。また、ｄｓ［ｍ］は、車両の微小移動距離を表わし、車速センサ１８の出力信号（車輪速パルス）を時間積分することによって監視される。尚、車両角度θ［ｒａｄ］は、旋回走行の際に生ずる車両の向きの変化角である。式（１）におけるｇ（Ｈａ）は、旋回曲率であり、舵角センサ１６から得られる舵角Ｈａを引数とし、所定の旋回特性マップ（図７参照）から求められる。旋回特性マップは、一定間隔毎の定常舵角で車両を周回させた際の、ＲＴＫ−ＧＰＳ（Ｒｅａｌ Ｔｉｍｅ Ｋｉｎｅｍａｔｉｃ ＧＰＳ）による測定される実際の旋回曲率に基づいて作成されてよい。

In each equation, θ, X, and Y are defined in a two-dimensional coordinate system with the vehicle width direction as the X axis and the vehicle front-rear direction as the Z axis, with the center of the rear wheel axis of the vehicle as the origin, and X ₀ , Y ₀ is a coordinate value of the center of the rear wheel axis of the vehicle at the reference vehicle position. Further, ds [m] represents a minute movement distance of the vehicle, and is monitored by time-integrating the output signal (wheel speed pulse) of the vehicle speed sensor 18. Note that the vehicle angle θ [rad] is a change angle of the direction of the vehicle that occurs during turning. G (Ha) in Expression (1) is a turning curvature, and is obtained from a predetermined turning characteristic map (see FIG. 7) using the steering angle Ha obtained from the steering angle sensor 16 as an argument. The turning characteristic map may be created based on an actual turning curvature measured by RTK-GPS (Real Time Kinetic GPS) when the vehicle is turned at a steady steering angle at regular intervals.

  The parking space information generation unit 45 relates to two parking spaces in the order of the left and right in the FIFO (first-in, first-out) method for each parking space, with respect to a plurality of parking spaces that can be detected by the parking space detection unit 41. Parking space information is generated. Therefore, assuming the case where the vehicle travels from position A0 to position A1 in the parking lot situation as shown in FIG. 6, the parking space information generation unit 45 is left until the parking space S3 is detected for the left side of the vehicle. When the parking space information related to the latest parking space S2 and the parking space information related to the next new parking space S1 are generated and the parking space S3 is detected, the generation of the parking space information related to the parking space S1 is generated. Instead, the parking space information related to the latest parking space S3 and the parking space information related to the next new parking space S2 are generated. Similarly, the parking space information generation unit 45, for the right side of the vehicle, until the parking space S6 is detected, the parking space information related to the latest parking space S5, and the parking space information related to the next new parking space S4, When the parking space S6 is detected, the generation of the parking space information related to the parking space S4 is stopped. Instead, the parking space information related to the latest parking space S6 and the next new parking space S5 are stopped. The parking space information related to is generated.

  In addition, the parking space information generation part 45 may generate | occur | produce parking space information at any time with respect to the parking space detected at any time in real time corresponding to the detection mode of the parking space of the parking space detection part 41, or For example, when the parking switch 52 is turned on at the parking start position, based on the storage data of the detection result of the parking space information generation unit 45 and the output results of the vehicle speed sensor 18 and the steering angle sensor 16 in the same section, Parking space information may be generated collectively.

  The parking space information storage unit 44 stores the parking space information generated by the parking space information generation unit 45 as needed in a FIFO manner for each parking space. The parking space information storage unit 44 of the present embodiment holds the parking space information regarding the two parking spaces in the order from left to right. Therefore, assuming that the vehicle has traveled from position A0 to position A1 in the parking lot situation as shown in FIG. 6, the parking space information storage unit 44 is left until the parking space S3 is detected for the left side of the vehicle. The parking space information related to the latest parking space S2 and the parking space information related to the next new parking space S1 will be held. When the parking space S3 is detected, the parking space information related to the parking space S1 is stored. It erase | eliminates from an area | region, and the parking space information concerning the newest parking space S3 and the parking space information concerning the next new parking space S2 are hold | maintained instead. Similarly, for the right side of the vehicle, the parking space information storage unit 44 stores the parking space information related to the latest parking space S5 and the parking space information related to the next new parking space S4 until the parking space S6 is detected. When the parking space S6 is detected, the parking space information related to the parking space S4 is erased from the storage area, and instead, the parking space information related to the latest parking space S6 and the next new parking space are deleted. The parking space information related to the space S5 is held.

  Next, processing realized by the deflection angle calculation unit 43 will be described. Output signals of the steering angle sensor 16 and the vehicle speed sensor 18 (see FIG. 1) are input to the deflection angle calculation unit 43 at predetermined intervals. The deflection angle calculation unit 43 calculates the amount of change in the direction of the vehicle in a predetermined section (hereinafter referred to as “deflection angle α”) based on the output signals of the steering angle sensor 16 and the vehicle speed sensor 18. The predetermined section is, for example, a section that is a predetermined distance (for example, 7 m) from the current vehicle position. The deflection angle α is defined as positive in the clockwise direction and negative in the counterclockwise direction. Here, in general, the deflection angle α can be calculated by the equation (2), where ds is the minute movement distance of the vehicle, and γ is the road surface curvature (corresponding to the reciprocal of the turning radius R of the vehicle). The expression of Equation 2 is to obtain the deflection angle α as a change in the direction of the vehicle from the position before βm (β = 7 in this example) to the local point.

偏向角演算部４３は、数１の式を変形した以下の数２の式に基づいて、所定の移動距離（本例では、０．５ｍ）毎の微小偏向角α_ｉを算出すると共に、算出した各微小偏向角α_１〜ｋを総和して偏向角αを算出する。

The deflection angle calculation unit 43 calculates a minute deflection angle α _i for each predetermined moving distance (0.5 m in this example) based on the following equation (2) obtained by modifying the equation (1). The deflection angles α are calculated by summing the small deflection angles α ₁ to _k .

この際、所定の移動距離（本例では、０．５ｍ）は、車速センサ１８の出力信号（車輪速パルス）を時間積分することによって監視される。また、路面曲率γは、舵角センサ１６から得られる舵角Ｈａに基づいて決定され、例えばγ＝Ｈａ／Ｌ・ηにより演算される（Ｌはホイールベース長、ηは車両のオーバーオールギア比（車輪の転舵角に対する舵角Ｈａの比）である）。尚、微小偏向角α_ｉは、微小移動距離０．０１ｍ毎に得られる路面曲率γに当該微小移動距離０．０１を乗算し、これらの乗算値を移動距離０．５ｍ分積算することによって算出されてもよい。尚、路面曲率γと舵角Ｈａとの関係は、予め車両毎に取得された相関データに基づいて作成されたマップ（図７参照）として、駐車支援ＥＣＵ１２のＲＯＭに格納されていてよい。

At this time, the predetermined moving distance (0.5 m in this example) is monitored by time-integrating the output signal (wheel speed pulse) of the vehicle speed sensor 18. The road surface curvature γ is determined based on the steering angle Ha obtained from the steering angle sensor 16, and is calculated by, for example, γ = Ha / L · η (L is the wheelbase length, η is the overall gear ratio of the vehicle ( The ratio of the steering angle Ha to the steering angle of the wheel)). The minute deflection angle α _i is calculated by multiplying the road surface curvature γ obtained every minute movement distance 0.01 m by the minute movement distance 0.01 and integrating these multiplied values by the movement distance 0.5 m. May be. The relationship between the road surface curvature γ and the steering angle Ha may be stored in the ROM of the parking assistance ECU 12 as a map (see FIG. 7) created based on correlation data acquired in advance for each vehicle.

The deflection angle α calculated in this way is used as a judgment material when the target parking space specifying unit 46 specifies and selects the parking space intended by the driver as will be described later. The detection results of the vehicle speed sensor 18 and the rudder angle sensor 16 (or the data of the minute deflection angle α _i based on the detection results) are the same as the detection results of the distance measuring sensor 70 even in a situation where the parking switch 52 is not turned on. It is desirable to be memorized. Thus, when the parking switch 52 is turned on, the deflection angle α in the section 7 m before the vehicle position at that time can be calculated retrospectively.

  Next, main processes realized by the target parking space specifying unit 46 will be described. FIG. 8 is a flowchart showing main processing realized by the target parking space specifying unit 46 in the garage parking scene. The processing routine shown in FIG. 8 is typically executed when the vehicle reaches the parking start position.

  In step 100, the target parking space specifying unit 46 determines whether the driver intends to park in the left or right parking space. Specifically, the target parking space specifying unit 46, based on the calculation result of the deflection angle calculation unit 43, when the deflection angle α in a section of a predetermined distance (for example, 7 m) from the current vehicle position is a positive value. It is determined that the direction of change of the vehicle direction is the right direction and the driver intends to park in the left parking space. Further, the target parking space specifying unit 46, based on the calculation result of the deflection angle calculation unit 43, when the deflection angle α in a section of a predetermined distance (for example, 7 m) from the current vehicle position is a negative value, It is determined that the direction of change of the vehicle direction is the left direction and the driver intends to park in the right parking space. If the determination is impossible, for example, when the deflection angle α is substantially zero, the driver may consider that the driver intends to park in the left parking space. Hereinafter, the description will be continued assuming a case where it is determined that the driver intends to park in the left parking space.

  In step 110, the target parking space specifying unit 46 determines whether or not the latest parking space valid flag set for the left parking space is valid at the current vehicle position. Whether or not the parking space valid flag is valid at the current vehicle position is whether or not the parking space according to the parking space valid flag is within a predetermined distance from the current vehicle position (parking start position). May be determined based on This is because there is a high possibility that the driver does not intend to park the parking space at a position far away from the current vehicle position. If the determination is affirmative, the process proceeds to step 120. If the determination is negative, the target parking space specifying unit 46 determines that the latest parking space in the parking space information storage unit 44 is intended by the driver. It is determined that it is not a parking space, and the process proceeds to step 150.

  In step 120, the target parking space specifying unit 46 extracts the position information relating to the latest parking space from the parking space information storage unit 44, and obtains the position (coordinates) of the latest parking space from the world coordinate system of the back monitor camera 20. Convert to camera coordinate system. This is to eliminate the influence of distortion or the like of the image captured by the lens of the back monitor camera 20.

  In step 130, the target parking space specifying unit 46 has the latest coordinate position of the parking space obtained by converting into the camera coordinate system in the imaging space captured by the back monitor camera 20 at the parking start position. Determine whether or not. That is, the target parking space specifying unit 46 determines whether or not the latest parking space position is within the viewing angle of the back monitor camera 20 at the parking start position. When the latest coordinate position of the parking space does not exist in the imaging space captured by the back monitor camera 20 at the parking start position, the target parking space specifying unit 46 is held in the parking space information storage unit 44. Of the two parking spaces, the latest parking space is determined not to be the parking space intended by the driver, and the process proceeds to step 150. Otherwise, the process proceeds to step 140.

  In Step 140, the target parking space specifying unit 46 determines that the latest parking space of the two parking spaces held in the parking space information storage unit 44 is the parking space intended by the driver, The latest parking space is selected (specified) as a parking space to be supported (target parking space).

  In step 150, the target parking space specifying unit 46 determines whether or not the second new parking space valid flag set for the left parking space is valid at the current vehicle position. If the determination is affirmative, the process proceeds to step 160. If the determination is negative, the target parking space specifying unit 46 indicates that the latest parking space in the parking space information storage unit 44 is intended by the driver. It is determined that it is not a parking space, and the process proceeds to step 190.

  In step 160, the target parking space specifying unit 46 extracts the position information relating to the second new parking space from the parking space information storage unit 44, as in step 120 above, and the position (coordinates) of the second new parking space. ) From the world coordinate system to the camera coordinate system of the back monitor camera 20.

  In step 170, the target parking space specifying unit 46, as in step 130 above, captures the second new parking space position (coordinates after conversion) by the back monitor camera 20 at the parking start position. It is judged whether it exists in. When the position of the second new parking space does not exist in the imaging space captured by the back monitor camera 20 at the parking start position, the target parking space specifying unit 46 is held in the parking space information storage unit 44. It is determined that the second new parking space of the two parking spaces is not the parking space intended by the driver, and the process proceeds to Step 190. Otherwise, the process proceeds to Step 180. move on.

  In step 180, the target parking space specifying unit 46 determines that the second newest parking space among the two parking spaces held in the parking space information storage unit 44 is the parking space intended by the driver. The second new parking space is selected (specified) as the parking space (target parking space) to be supported.

  In step 190, the target parking space specifying unit 46 determines that none of the two parking spaces held in the parking space information storage unit 44 is the parking space intended by the driver, and determines the two parking spaces. Then, the candidate parking spaces (target parking spaces) to be supported are discarded (that is, the two parking spaces are invalidated).

  When the target parking space specifying unit 46 specifies the parking space (target parking space) to be supported in this way, the target parking space specifying unit 46 notifies the information output control unit 42 of the specified target parking space. In addition, when the above-described step 190 is performed, that is, when the parking space intended by the driver is not specified, the information output control unit 42 is notified to that effect.

  By the way, in the case of parking in a garage, when passing through a parking space intended for parking, the driver tends to start turning the handle in a direction away from the parking space and reach a parking start position suitable for the parking space. is there. Therefore, in general, the parking space intended by the driver is highly likely to be a parking space detected immediately before reaching the parking start position.

  However, as shown in FIG. 9, for example, the parking space that the driver intends to park is the parking space S3, and the driver starts turning the steering wheel immediately after passing the parking space S3, and the parking start position A2 is reached. Assuming the case, if there is a space behind the obstacle Z3 that defines the parking space S3, a new parking space S7 is created after starting to turn the handle (just before reaching the parking start position). It may be detected by the parking space detection unit 41.

  Therefore, in the configuration in which the most recently detected parking space is specified as the parking space that the driver intends to park, the parking space that the driver does not intend (in this example, the parking space S7) is set as the target parking space. It will be specified.

  On the other hand, in the present embodiment, as described above and as shown in FIG. 10, even when the parking space is detected most recently, it does not fall within the imaging range of the back monitor camera 20 at the parking start position. Since it is not specified as the target parking space, as shown in FIG. 10, the parking space S7 is not erroneously specified as the target parking space, and the imaging range of the back monitor camera 20 is set at the parking start position. The second new parking space S3 to be entered can be appropriately specified as the target parking space. As described above, according to the present embodiment, the target parking space suitable for the driver's intention is accurately selected and specified by determining the driver's intention using the imaging range of the back monitor camera 20. Can do.

  The information output control unit 42 is based on the parking space information stored in the parking space information storage unit 44, at a position (position on the screen) corresponding to the target parking space specified by the target parking space specifying unit 46. The initial display of the target parking frame is performed. Specifically, when the reverse shift switch 50 is turned on at the parking start position, the information output control unit 42 shoots a landscape in a predetermined angle area behind the vehicle on the display 22 provided in the vehicle interior. A captured image (actual image) of the camera 20 is displayed. At this time, as shown in FIG. 11 (screen for parking in a garage), the target parking frame is superimposed on the captured image on the display 22. The target parking frame may be a figure imitating the actual parking frame or the outer shape of the vehicle. For example, the target parking frame has a form in which the position and orientation can be visually recognized by the user, and is displayed for parking in a garage (parallel parking). And two types of display for parallel parking may be prepared.

  The initial display position / orientation of the target parking frame displayed on the display 22 corresponds to the position and orientation related to the target parking space specified as described above (position and orientation based on the parking space information). The position / orientation of the target parking frame may be determined as it is by the final operation of the determination switch by the user. Alternatively, as shown in FIG. 11, the position of the target parking frame can be adjusted before the operation of the confirmation switch by a touch switch for moving the target parking frame up and down, left and right, and rotating. Also good.

  According to the present embodiment, as described above, even when a parking space not intended by the driver is detected immediately before reaching the parking start position, the parking space on the side that is likely to match the driver's intention. Is specified as the target parking space, and the initial display position of the target parking frame is determined based on the specified target parking space, so that the driver initially displays the target parking frame at an appropriate position where parking is intended. (It is possible to prevent the driver from displaying the target parking frame corresponding to the opposite parking space where parking is not intended). This eliminates the need to adjust the target parking frame by operating the touch switch many times, as in the case where the target parking frame is displayed at a position in the parking space different from the driver's intention. The time required for setting can be greatly reduced.

  When the position or the like of the target parking frame is determined by an operation by the user, the target parking position determination unit 49 determines the target parking position and the target parking direction with respect to the target parking space based on the position and orientation of the target parking frame. The target parking position may correspond to the coordinate value of the position of the center of the vehicle rear wheel axis in the target parking space.

  The target movement trajectory calculation unit 48 calculates a target movement trajectory based on the target parking position and the target parking direction determined by the target parking position determination unit 49. When the rearward movement of the vehicle is started, the information output control unit 42 uses the vehicle movement amount calculated from the output signal of the vehicle speed sensor 18 and the steering angle position obtained from the steering angle sensor 16 during the automatic guidance control. The target steering angle is calculated according to the deviation of the estimated vehicle position from the target movement trajectory, and the target steering angle is transmitted to the steering control ECU 30. The steering control ECU 30 controls the motor 32 so as to realize the target steering angle. The motor 32 may be provided in a steering column or a steering gear box and rotate the steering shaft according to the rotation angle.

  The target movement trajectory calculation unit 48 estimates and calculates the vehicle position during execution of parking assistance based on the output signals of the steering angle sensor 16 and the vehicle speed sensor 18, and calculates the target movement trajectory calculated last time and the estimated vehicle position. Depending on the difference, the current target movement trajectory may be calculated, and the target steering angle at the estimated vehicle position described above may be determined based on the target movement trajectory. The calculation of the target movement trajectory may be performed every time the vehicle moves by a predetermined movement distance (for example, 0.5 m). At this time, the target movement trajectory calculation unit 48 appropriately corrects the target parking position / target parking direction (according to the calculation of the target movement trajectory) based on the parking frame line recognition processing result for the captured image of the back monitor camera 20. May be.

  The information output control unit 42 requests the driver to stop the vehicle when the vehicle is finally placed in the target parking position in the parking space in the target parking direction (or the vehicle is automatically driven by the automatic braking means). Stop) and parking support control is completed.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, in the above-described embodiment, whether or not the detected parking space exists in the imaging space imaged by the back monitor camera 20 at the parking start position is determined by the coordinates of a specific point in the parking space. It is determined based on whether or not it exists in the imaging space imaged by the back monitor camera 20 at the parking start position, but the coordinates of two or more specific points in the parking space are within the imaging space. It may be determined based on whether or not it exists. Further, whether or not the detected parking space exists in the imaging space imaged by the back monitor camera 20 at the parking start position is determined based on the coordinates of a specific point in the parking space in the imaging space. You may judge based on whether it exists in a predetermined space. The imaging space imaged by the back monitor camera 20 at the parking start position may be any imaging space that is substantially imaged by the back monitor camera 20 at the parking start position, and is imaged immediately before the parking start position. It is also possible to replace it with different imaging space.

  In the above-described embodiment, the target parking space specifying unit 46 performs an angle-of-view determination as to whether or not the parking space exists within the angle of view of the back monitor camera 20 when the vehicle reaches the parking start position. However, the same angle of view determination may be performed during advance to the parking start position. That is, the target parking space specifying unit 46 performs angle-of-view determination on the parking space detected by the parking space detection unit 41 at any time while moving forward to the parking start position, and the detected parking space is detected. It may be determined whether or not the parking space is intended by the driver. In this case, since the parking space intended by the driver can be specified during the advance to the parking start position, for example, the parking initial stage such as the notification guidance of the parking space or the travel guidance to the parking start position. It is possible to provide parking assistance at

  Moreover, in the above-mentioned Example, in order to reduce the processing burden of the parking space information generation part 45, and to utilize efficiently the storage capacity of the vehicle space memory | storage part 44, the parking space which concerns on a new parking space 2 each left and right Although it is supposed to generate and hold information, it is also possible to generate and hold parking space information related to three or more new parking spaces on the left and right.

  Further, in the above-described embodiment, in the target parking position setting screen shown in FIG. 11, the target parking frame is located at a position (position on the screen) corresponding to the target parking space specified by the target parking space specifying unit 46. Although the initial display is based on the detection data of the distance measuring sensor 70, the present invention is not limited to this. For example, the parking frame line (white line) is recognized based on the captured image of the back monitor camera 20, and the target parking space specified by the target parking space specifying unit 46 based on the image recognition result (the position of the parking frame line). The target parking frame may be initially displayed at a position corresponding to the space (position on the screen). However, the above-described embodiment is particularly suitable for a parking lot where such a parking frame line does not exist or when a parking frame line cannot be recognized.

  Further, in the above-described embodiment, on the assumption that there is a parking space that can be supported at the parking start position, the target parking frame is initially displayed in correspondence with the position of the parking space. For example, when the parking space is not specified (see step 190 in FIG. 8) or when sufficient data cannot be acquired by the distance measuring sensor 70, for example, the information output control unit 42 sets the parking start position at the parking start position. The parking position intended by the driver may be estimated on the basis of the travel pattern of the vehicle up to and the target parking frame may be initially displayed in correspondence with the estimated parking position. Alternatively, when the information output control unit 42 determines that there is a temporary stop in the process of reaching the parking start position based on the detection result of the vehicle speed sensor 18 (for example, the predetermined moving distance 6 before reaching the parking start position 6). If it is determined that there was a stop within 0.5 m), the position that is in a predetermined relative relationship to the temporary stop position at that time is estimated to be the parking position intended by the driver, and the estimated The target parking frame may be initially displayed in correspondence with the parking position. The method for determining the initial display position of the target parking frame based on the temporary stop position is described in detail in, for example, Japanese Patent Application Laid-Open No. 2004-345496.

  In the above-described embodiment, the distance measuring sensor 70 suitable as the obstacle detection unit is used. However, it is also possible to detect an obstacle (and thus a parking space) by image recognition of the camera.

  Further, the memory 72 may be a dedicated memory for storing detection data of the distance measuring sensor 70 or a memory in the parking assist ECU 12. In the former case, other data may be stored in a memory in the parking assist ECU 12.

  In the above-described embodiment, for the sake of explanation, the obstacle is assumed to be a vehicle. However, as the obstacle, any tangible object such as a bicycle, a two-wheeled vehicle, a wall, and two or more pylons can be assumed.

  In the above-described embodiment, the vehicle speed sensor 18, the steering angle sensor 16, and the deflection angle calculation unit 43 obtain and derive information related to the vehicle direction, but instead of or in addition, a yaw rate sensor, a gyro sensor, An azimuth meter, a GPS positioning result, or the like may be used.

1 is a system configuration diagram showing an embodiment of a parking assistance device 10 according to the present invention. 2 is a schematic diagram illustrating an example of an angle of view of a back monitor camera 20. FIG. It is explanatory drawing which shows the detection aspect of the object (in this example, vehicle Z) of the detection target of the ranging sensor. It is the schematic which shows the point sequence which concerns on the vehicle Z obtained when the vehicle (own vehicle) provided with the ranging sensor 70 drive | works near the vehicle Z of FIG. It is a block diagram which shows the main functions of parking assistance ECU12 of a present Example. It is a top view which shows the condition of the parking lot for garage parking. It is a figure which shows an example of a turning characteristic map. It is a flowchart which shows the main processes implement | achieved by the target parking space specific | specification part 46 in the scene of garage parking. It is a top view which shows the condition of a typical parking lot in case a new parking space is detected by the parking space detection part 41 just before reaching a parking start position. It is a figure which shows the relationship between the imaging range of the back monitor camera 20, and detected parking space S3, S7. It is a figure which shows an example of the display mode of the target parking frame on the display.

Explanation of symbols

10 Parking assistance device 12 Parking assistance ECU
16 Steering angle sensor 18 Vehicle speed sensor 20 Back monitor camera 22 Display 30 Steering control ECU
DESCRIPTION OF SYMBOLS 41 Parking space detection part 42 Information output control part 43 Deflection angle calculation part 44 Parking space information storage part 45 Parking space information generation part 46 Target parking space specific | specification part 48 Target movement track | orbit calculation part 49 Target parking position determination part 50 Reverse shift switch 52 Parking switch 70 Distance sensor

Claims (5)

In the parking support device that supports parking for the target parking space,
Imaging means for imaging the vehicle rear area;
Obstacle information acquisition means for acquiring obstacle information around the vehicle in the process of the vehicle reaching the parking start position;
A parking space detecting means for detecting a parking space based on the obstacle information acquired by the obstacle detecting means;
A target parking space specifying means for specifying a target parking space from among the parking spaces detected by the parking space detecting means;
The target parking space specifying means specifies a target parking space based on a positional relationship between a parking space detected by the parking space detecting means and an imaging space imaged by the imaging means. Parking assistance device.   The target parking space specifying unit specifies, as a target parking space, a parking space existing in an imaging space captured by the imaging unit at a parking start position among parking spaces detected by the parking space detecting unit. The parking assistance device according to claim 1. Display means for displaying a vehicle rear image captured by the imaging means;
Display control means for superimposing and displaying a target parking frame that can be moved by the user on the vehicle rear image when the vehicle is present at the parking start position;
A target parking position determining means for determining a target parking position based on the position of the target parking frame on the vehicle rear image;
The parking support device according to claim 1 or 2, wherein the display control means initially displays the target parking frame at a position corresponding to the target parking space specified by the target parking space specifying means on the vehicle rear image. . In the parking support device that supports parking for the target parking space,
Imaging means for imaging the vehicle rear area;
Display means for displaying a vehicle rear image captured by the imaging means;
Display control means for superimposing and displaying a target parking frame that can be moved by the user on the vehicle rear image when the vehicle is present at the parking start position;
Obstacle information acquisition means for acquiring obstacle information around the vehicle in the process of reaching the parking start position;
Based on the obstacle information acquired by the obstacle detection means, a parking space detection means for detecting a parking space existing around the vehicle in the process of reaching the parking start position;
Parking space storage means for sequentially storing position information regarding the parking space detected by the parking space detection means;
The position information on the latest parking space stored in the storage means is read out, and it is determined whether the read out parking space exists in the imaging space imaged by the imaging means at the parking start position, and the reading is performed. If it is determined that the parking space does not exist in the imaging space, the next new parking space stored in the storage means is read, and whether or not the read parking space exists in the imaging space is determined. A target parking space specifying means for judging,
The display control means initially displays the target parking frame at a position corresponding to the parking space when the parking space existing in the imaging space is specified by the target parking space specifying means. Parking assistance device. The parking space storage means is configured to store at least two parking spaces detected on the left and right sides of the vehicle separately from the left and right in order from the newest one,
The target parking space specifying unit selects one of left and right, and sequentially reads out the latest parking space on the selected side from among the parking spaces stored in the parking space storage unit, and performs the determination process. 4. The parking assistance device according to 4.

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