DE102008022199B4 - Parking assist system - Google Patents

Abstract

A parking assist system installed in a vehicle, the parking assist system comprising: own vehicle position estimating means (1) estimating a position and a moving direction of the native vehicle; a distance detecting means (2) detecting an obstacle around the system's own vehicle; obstacle estimation means (3) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means (4) which estimates a position of a target parking space on the basis of the output of the obstacle estimation means; means guided assistance (6) that instructs the target parking space estimation result or supports entry into the target parking space, characterized by parking space detection position identification means (7) that sets a parking space detection start position and end position based on at least the output of the own vehicle position estimation means and means (5, 25, 35, 45, 55, 65, 75, 85) for judging the appropriateness of the output of the target space estimating means; wherein the guided assistance means (6) instructs the target parking space estimation result based on the outputs of the estimated space appropriateness estimating means and the target space estimating means, or assists entry into the target parking space.

Description

BACKGROUND

1. Technical area

The present invention relates to a parking assist system for alleviating the burden of a driver during parking, and more particularly to a parking assist system capable of determining the desirability of destination parking assist based on an estimation result of the own vehicle position and an obstacle estimation result.

2. State of the art

When a vehicle is parked, it is first necessary for a driver to search for a target parking space, and during this search for a parking space, the driver must judge whether or not there is sufficient space in which the driver can park his own vehicle, which is no small burden for the driver. In order to mitigate this burden on the driver during parking, there has conventionally been proposed parking assistance systems which aid operation by the driver during parking, and methods for determining the desirability of such assistance have also been proposed.

For example, there is a parking space detection system that uses a positioning sensor to detect objects around a parking space while the native vehicle is traveling. The system then divides detection points detected using, as a boundary, a reference line that is a first distance away from a side of the native vehicle, detection points on a front side, and detection points on a depth side of the parking space. From the detection points on the front side, the system recognizes, as the width of the parking space, intervals between detection points that are a second distance or farther away, and detects than the depth of the parking space, intervals between detection points that are on the front side, and intervals between detection points that are on the depth side. The system compares the detected parking space with the size of the native vehicle stored to determine whether or not the native vehicle can be parked in that space (see, for example, FIG. JP 2007-131 169 A ).

Incidentally, arise in the parking space detection system of JP 2007-131 169 A Variations in the position of the native vehicle when z. For example, as the native vehicle snakes, so that the detection result also varies and it becomes difficult for the parking space detection system to accurately recognize the target parking space. Further, when the movement speed of the native vehicle is fast and target detection accuracy is poor, it is difficult for the parking space detection system to identify the position of the native vehicle, so that it becomes difficult for the parking space detection system to accurately recognize the target parking space, and there was a danger the native vehicle ends up being guided by parking assist control to a space not intended by the driver, or the native vehicle ends up touching an obstacle.

In JP 2007-131 169 A It is disclosed that the parking space detection system may also terminate detection using the vehicle speed of the native vehicle as a condition for determining the convenience of assistance, since detection of the target parking space becomes difficult when the vehicle speed of the native vehicle is greater than a reference value. Further, in JP 2007-71 536 A discloses a method that predicts the number of reflection points from an obstacle, and since detection of the target parking space becomes difficult when this number is smaller than a predetermined number, estimation of the target space using the number of obstacle detection points as a condition for determining the convenience does not perform a support.

In the aforementioned methods for determining the convenience of assistance by parking assistance systems, the condition is in any case insufficient and can not be provided for practical use. Ie. in JP 2007-131 169 A however, the vehicle speed of the native vehicle is used as a condition for determining the convenience of assistance, but during the process of detecting the target parking space, the vehicle speed changes, and depending on when the parking assist system judges the convenience of assistance by the vehicle speed Cases where a good effect is obtained, but cases are conceivable where support control is frequently terminated.

Further, in JP 2007-71 536 A the number of obstacle detection points is used as a condition for determining the convenience of assistance, but the number of detection points is influenced by the vehicle speed of the native vehicle, so that when z. B. a threshold value of a number of detection points in accordance with a low Vehicle speed is finally set, an assistance control finally ends up being terminated even if the vehicle speed increases slightly higher than the vehicle speed used in the threshold setting and the number of detection points decreases. Conversely, when a threshold value of a number of detection points is set in accordance with a high vehicle speed, the number of detection points becomes lower for reasons other than vehicle speed, but when the threshold value is exceeded, the pair support system attempts to reduce the target parking space by a smaller number of detection points as it originally does, and eventually ends up estimating a faulty space as a result, and performs assistance control that compromises the sense of reliability the driver has with respect to the system.

DE 10 2005 032 095 A1 describes a parking device for supporting a parking operation, in which sensors detect a vehicle environment and an evaluation unit determines an alignment of the parking space based on the parking space environment.

DE 10 2006 060 457 A1 shows a method and system for assisting a driver when parking or maneuvering a motor vehicle with at least one driver assistance system and one vehicle safety system.

DE 103 16 101 A1 teaches a method and apparatus for detecting a vehicle spacing, wherein stability in detecting a distance to a preceding vehicle is improved by calculating a distance to the preceding vehicle using reflected waves of a radar beam.

SUMMARY OF THE INVENTION

The present invention has been made to address these problems, and it is an object of the invention to realize a parking assist system that can reliably and safely assist a driver's parking.

To achieve this object, this invention is a parking assist system installed in a vehicle, the parking assist system incorporating all the features of claim 1. Further advantageous embodiments will become apparent from the claims 2-9.

This invention may terminate guidance resulting from parking assist when e.g. B. the native vehicle snakes driving when the movement speed of the native vehicle is fast and target detection accuracy is poor or when an actual right-left wheel speed difference that is detected, and a right-left wheel speed difference of the native vehicle, which consists of a steering angle of the natively estimated to be equal to or greater than a predetermined value, and can effectively prevent a situation where the native vehicle ends up being guided by a parking assist control to a space unintended by the driver or where the native vehicle it ends up touching an obstacle.

The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

1 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 1 of this invention;

2 Fig. 10 is a flowchart showing a processing sequence in Embodiment 1 of this invention;

3 FIG. 10 is a flowchart showing estimation processing of own vehicle position in the flowchart of FIG 2 shows;

4 FIG. 12 is a flowchart illustrating the parking space detection position processing in FIG 2 shows;

5 FIG. 11 is a flowchart illustrating obstacle estimation processing in FIG 2 shows;

6 FIG. 10 is a flowchart illustrating target space estimation processing in FIG 2 shows;

7 FIG. 10 is a flowchart showing processing for judging appropriateness of an estimated space in FIG 2 shows;

8th FIG. 11 is a flowchart illustrating processing assistance in 2 shows;

9 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 2 of this invention;

10 FIG. 14 is a flowchart illustrating processing for judging appropriateness of a estimated space in Embodiment 2 of this invention;

11 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 3 of this invention;

12 Fig. 10 is a flowchart showing an estimated space adequacy judgment processing in Embodiment 3 of this invention;

13 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 4 of this invention;

14 Fig. 10 is a flowchart showing estimated space adequacy judgment processing in Embodiment 4 of this invention;

15 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 5 of this invention;

16 Fig. 10 is a flowchart showing estimated space adequacy judgment processing in Embodiment 5 of this invention;

17 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 6 of this invention;

18 Fig. 10 is a flowchart showing an estimated space adequacy judgment processing in Embodiment 6 of this invention;

19 Fig. 10 is a flowchart showing an estimated space adequacy judgment processing in Embodiment 7 of this invention;

20 Fig. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 8 of this invention; and

21 FIG. 10 is a flowchart showing processing for judging adequacy of an estimated space in Embodiment 8 of this invention. FIG.

DETAILED DESCRIPTION

Embodiment 1

Hereinafter, embodiments of a parking assist system will be described with reference to the drawings. 1 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 1. FIG. Each block may be configured individually or holistically by a common computer (configured by a ROM, a RAM, a CPU, an I / O, etc.), not shown, and is configured to perform a predetermined operation by various types of software included in the ROM and the RAM is included.

In 1 is 1 an estimation means of the own system position which estimates a position of the native vehicle, 2 is a distance detection means which detects a distance to an obstacle, 3 is an obstacle estimation means which determines a position and a corner shape of an obstacle from the outputs of the estimation means of the own system position 1 and the distance detection means 2 estimates 4 A target space estimating means is a position of a target parking space based on the output of the obstacle estimating means 3 estimates 5 is a means for judging the appropriateness of an estimated space that the appropriateness of the output of the target space estimation means 4 on the basis of the expenses of the estimate of own system position 1 , the obstacle estimation tool 3 and a parking space detection position identifying means described later 7 judged, and 6 is a means of guided assistance that performs a guided support of the Native Vehicle to be parked based on the outputs of the target space estimation means 4 and the means for judging the appropriateness of an estimated space 5 , 7 represents a parking space detection position identification means which sets a start position and an end position for parking space detection.

It is noted that in the present embodiment, a description will be given where a wheel speed sensor and a steering angle sensor z. As the estimation means of the own vehicle position 1 but the agent used is not limited to these, and other means may be used. Further, in the present embodiment, an ultrasonic sensor is used as the distance detecting means 2 but other means may be used. In addition, in the present embodiment, a sound guide coming out of a speaker becomes the means of guided assistance 6 however, the agent used is not limited to this, and other means may be used.

Next, an operation of the present embodiment will be described. 2 FIG. 10 is a flow chart showing an overview of a processing sequence of the parking assist system. FIG in the present embodiment. In the estimation processing of own vehicle position (step 11 ), the parking assist system estimates the position and the moving direction of the native vehicle on the basis of the outputs of the wheel speed sensor and the steering angle sensor that the own vehicle position estimating means 1 configure. 3 FIG. 10 is a flowchart showing the processing sequence of this own vehicle position estimation processing 11 shows. The parking assist system detects a wheel speed V of the native vehicle from the wheel speed sensor (step 111 ) and next detects a steering angle Θ of the native vehicle from the steering angle sensor (step 112 ). The parking assist system calculates an X coordinate (step 113 ) and a Y coordinate (step 114 ) of the position of the native vehicle on the basis of the wheel speed V and the steering angle Θ of the native vehicle which have been detected.

The method of calculating the X coordinate and the Y coordinate will be specifically described. Assuming that N represents a number of revolutions, which is a count of the wheel speed sensor, and that 1 m represents a pitch per revolution, then a moving distance L of the native vehicle becomes 1 × N, and the parking assist system takes coordinates (Xc ', Yc ') of the moving distance L by Xc' = L × sinΘ and Yc '= L × cosΘ in the direction of the steering angle Θ of the native vehicle detected by the steering angle sensor with respect to an origin (0, 0). The parking assist system adds the previous (previous period) coordinate of the position of the native vehicle (Xco, Yco) as an offset to these coordinates (Xc ', Yc') Xc = Xc '+ Xco, Yc = Yc' + Yco

The parking assist system uses the coordinates (Xc, Yc) calculated as the current position of the native vehicle and sequentially calculates it in accordance with the running of the native vehicle. It is noted that the parking assist system uses the origin of the position of the native vehicle and the position coordinate system of an obstacle as a parking space detection start position.

After calculating the X-coordinate and the Y-coordinate, the parking assist system calculates the direction of movement (step 115 ) and the movement distance (step 116 ) of the native vehicle from the wheel speed V and the steering angle Θ of the native vehicle. It is noted that the parking assist system can also calculate the moving distance of the native vehicle from only the output of the wheel speed sensor.

Next 2 Turning to the processing sequence moves to the parking space detection position identification processing (step 12 ) after the estimation of the own vehicle position (step 11 ). 4 FIG. 10 is a flowchart showing the processing sequence of the parking space detection position identification processing (step 12 ) shows. In 4 The parking assist system compares the wheel speed V detected by the wheel speed sensor with a parking space detection start threshold V ₁ (step 121 ). The parking assist system uses the timing when the wheel speed V becomes equal to or less than the threshold value V ₁ as a parking space detection start position, and sets a parking-in detection flag (step 122 ).

The parking space detection start threshold V1 is set in a range where the parking assist system can estimate the corner shape of an obstacle from many detection points (distance detection result) obtained by the ultrasonic sensor in accordance with the running of the native vehicle. Assuming that the ultrasonic sensor performs transmission in a predetermined period, when the ultrasonic sensor detects a certain target, the higher the vehicle speed of the native vehicle, the number of ultrasonic sensor detection points becomes smaller, and conversely, the number of ultrasonic sensor detection points becomes larger the lower the vehicle speed of the native vehicle. Accordingly, in consideration of the area where the parking assist system can estimate the corner shape of the obstacle, the vehicle speed threshold V1 that determines the start of detection is set to a low value, such as, for example. B. 20 km / h.

Next, the parking assist system detects the timing when the vehicle speed V detected by the wheel speed sensor becomes equal to a threshold value V2 as a parking space detection end position (step 123 ) clears the parking space in detection flag (step 124 ) and sets a parking space completion completion flag (step 125 ). The vehicle speed threshold V ₂ , which determines the end of detection of a parking space, is set to a value (such as 0 km / h) where the parking assist system becomes capable of obtaining sufficient many detection points (distance detection result) for estimating the corner shape of the obstacle is after the vehicle speed of the native vehicle becomes equal to or less than V ₁ and the parking assist system detects the parking space starts. It is noted that, in the present embodiment, the parking assist system uses the vehicle-own-vehicle wheel speed as a condition for determining parking-space start and end detection, but the parking assist system may also use the end-of-detection timing as a starting point and a position including a parking space predetermined distance from there goes back to use as the detection start position. Further, the condition for determining the parking space detection start position and detection end position is not limited to these, and other conditions may be used.

As mentioned above, by arranging the parking space detection position identifying means 7 and limiting detection of a parking space to a detection end position from a detection start position, the parking assist system may be able to more reliably acquire the detection points of the ultrasonic sensor, and the parking assist system may more reliably perform an estimate of the corner shape of the obstacle. Thus, the parking assistance system will be able to schedule assistance when guidance resulting from parking assistance is difficult and only performing assistance when it is judged that guidance is possible.

After parking space position identification, the processing sequence moves to obstacle estimation processing (step 13 ) from 2 , 5 FIG. 10 is a flowchart showing the processing sequence of this obstacle estimation processing 13 shows. The parking assist system obtains the result of detecting the distance to the obstacle from the input of the ultrasonic sensor (step 131 ). On the basis of the detected distance to the obstacle and the estimation result of the own vehicle position, the parking assist system calculates the X-coordinate (step 132 ) of the obstacle and the Y-coordinate (step 133 ) of the obstacle in the same coordinate system as the position of the native vehicle. Regarding the method of calculating the coordinates of the obstacle, the parking assist system first uses the position of the native vehicle as an origin (0, 0), and sets a coordinate (d, 0) in a position away from the distance d in the X-axis direction Origin based on the distance detection result d of the input from the ultrasonic sensor. The parking assist system rotates this coordinate (d, 0) by the steering angle Θ detected by the steering angle sensor. Xo '= d × cosΘ + 0 × sinΘ, Yo' = -d × sinΘ + 0 × cosΘ

The parking assist system adds the coordinates (Xc, Yc) of the position of the native vehicle as an offset to the calculated coordinates (Xo ', Yo'). Xo = Xo '+ Xc, Yo = Yo' + Yc

The parking assist system uses the coordinates (Xo, Yo) thus calculated as the obstacle coordinates and calculates them with respect to all the detection points input from the ultrasonic sensor.

Next, the parking assist system calculates an approximate turn (step 134 ) that intersects the coordinates of the obstacle that is continuously detected in accordance with the travel of the native vehicle, and uses this as a material to estimate the corner shape of the obstacle. The parking assist system estimates a circle centered around the coordinates of the native vehicle position whose radius is the distance to the approximate curved coordinate of the obstacle, and calculates the intersection of two circles that are predetermined.

The parking assist system calculates a corrected value of the X-coordinate of the obstacle (step 135 ) and a corrected value of the Y-coordinate of the obstacle (step 136 ) using this intersection as a corrected coordinate of the obstacle, and the result of multiplying these corrected values of the coordinate in accordance with the travel of the native vehicle becomes the estimated corner shape of the obstacle.

After the obstacle estimation, the processing sequence moves to the target space estimation processing (step 14 ) from 2 , 6 FIG. 10 is a flowchart showing the processing sequence of the target space estimation processing 14 shows. From the obstacle estimation result, the parking assist system calculates the length and width of the space estimated to be the one where the obstacle does not exist (steps 141 and 142 ).

If it is z. For example, if there are no detection points in the input from the ultrasonic sensor, the obstacle is not present in the detection range of the ultrasonic sensor - that is, the parking assist system estimates the detection range of the ultrasonic sensor (maximum detection distance) as the width of the target space. On the other hand, when there are detection points in the input from the ultrasonic sensor, the parking assist system understands the distance to the obstacle by the distance detection result thereof and used this as a target space. The parking assist system estimates the length of the target space from the estimation result of the own vehicle position (moving distance of the native vehicle) based on the wheel speed sensor output.

After the target space estimation, the processing sequence moves to the estimated space estimation processing (step 15 ). 7 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 15 shows. If the parking space in detection flag is set (step 151 ), the parking assist system first calculates a sum Θ _{ALL of} the steering angles Θ of the native vehicle (step 152 ). When the parking space detection completion flag is set (step 153 ), the parking assist system next calculates a mean value Θ _{AVE of} the calculated steering angle sum Θ _ALL (step 154 ) and calculates a standard deviation σ _{Θ of} the steering angle _sum average Θ _AVE (step 155 ). Then, the parking assist system clears the parking space acquisition completion flag (step 156 ).

The parking assist system compares the steering angle sum mean value standard deviation σ _Θ with a threshold value Θ _TK (step 157 ), and when the steering angle sum mean standard deviation σ _{Θ is} smaller than the threshold value Θ _TH , the parking assist system judges that the target space estimation result is appropriate, and allows use of this result (step 158 ). When the calculated steering angle mean mean standard deviation σ _{Θ is} equal to or greater than the threshold value Θ _TH , the parking assist system judges that the target space estimation result is not appropriate and does not allow use of this result (step 159 ). After judging the appropriateness of an estimated space, the processing sequence moves to the guided assist processing (step 16 ).

8th FIG. 10 is a flowchart showing the processing sequence of guided assistance processing (step 16 ). In the processing for judging the appropriateness of an estimated space (Step 15 ) if use of the target space estimation result is allowed (step 161 ), the parking assist system performs sound guidance using the speaker to notify the driver that it has detected a destination space in which the native vehicle can be parked, and notifies the position thereof (step 162 ). On the other hand, when in the processing for judging the appropriateness of an estimated space (step 15 ) is not allowed to use the target space estimation result, the parking assist system uses the speaker to notify the driver by sound that it is unable to detect a space in which the native vehicle can be parked (step 163 ).

As described above, according to Embodiment 1 of this invention, the parking assist system is configured to determine that the target space estimation result is not appropriate when the standard deviation of the mean value of the steering angles while the native vehicle is traveling from the parking space detection start position to the parking space detection end position is equal to or greater than a predetermined value so that the parking assist system can schedule a tour resulting from parking assistance when the parking assist system is unable to accurately detect a destination parking space, such as when the native vehicle is being parked, for example. B. snaking drives, and the parking assist system can more reliably and safely prevent a situation where the native vehicle ends up being guided to a space unintended by the driver and the native vehicle ends up touching an obstacle.

Embodiment 2

9 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 2. FIG. In 9 the same reference numerals are given to sections that are the same as or correspond to those in FIG 1 , In 9 is the only section that is different from 1 distinguishes the means of assessing the appropriateness of an estimated space 25 , and the other sections are completely the same as those in 1 so that a description thereof is omitted. 10 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 25 shows. In 10 added when the parking space in detection flag is set and there are detection points in the distance detection means (step 251 ), the parking assistance system 1 to the detection point counter (step 252 ) adds the vehicle speed and determines the sum thereof (step 253 ).

Calculated at this time, if the parking space detection completion flag is set (step 254 ), the parking assist system generates a vehicle speed average V _AVE from the vehicle speed sum (step 255 ) and clears the parking space detection completion flag (step 256 ). The parking assist system compares a detection point threshold N ₁ set in advance by the calculated one Vehicle speed _average V _AVE with the detection point counter (step 257 ), and when the detection point counter value is greater than the detection point threshold N ₁ , the parking assist system judges that the target space estimation result is appropriate and allows use thereof (step 258 ). On the other hand, if the detection point counter is equal to or smaller than the detection point threshold N ₁ , the parking assist system judges that the target space estimation result is not appropriate and does not allow employment thereof (step S4) 259 ). After determining whether or not to set the target space estimation result, the parking assist system sets the detection point counter to zero and initializes its status (steps 260 and 261 ).

By configuring the parking assist system as described above, the parking assist system sets a necessary number of obstacle detection points in accordance with the vehicle speed average of the native vehicle while the native vehicle is traveling from the parking space detection start position to the parking space detection end position and determines that the target space estimation result is not appropriate when the number of points is smaller than the necessary number of detection points, so that the parking assist system can schedule a guidance resulting from parking assistance when the parking assist system can not identify the position of the destination and is unable to accurately recognize the destination parking space such as when the cruising speed of the native vehicle is fast and target detection accuracy is poor, and the parking assist system can provide a more reliable and reliable situation to more securely prevent where the native vehicle ends up being led to a space unintended by the driver, and the native vehicle ends up touching an obstacle.

Embodiment 3

11 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 3. FIG. In 11 the same reference numerals are given to portions that are the same as those, or correspond to those in FIG 1 , In 11 is the only section that is different from 1 distinguishes, the means for judging the appropriateness of an estimated space 35 , and the other sections are completely the same as those in 1 so that a description thereof is omitted. 12 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 35 shows. When in 12 the parking space in detection flag is set and there are detection points in the distance detection means (step 351 ) adds the parking assistance system 1 to the detection point counter (step 352 ). Further, when the vehicle speed of the native vehicle acquired at this time is equal to or more than a maximum vehicle speed, the parking assist system stores the vehicle speed obtained at that time as a maximum vehicle speed (step 354 ).

At this time, if the parking space detection completion flag is set (step 355 ), the parking assist system clears the parking space detection completion flag (step 356 ). The parking assist system compares a detection point threshold N ₂ set in advance from the maximum vehicle speed determined during detection point acquisition with the detection point counter (step 357 ), and when the detection point counter value is larger than the detection point threshold N ₂ , the parking assist system judges that the target space estimation result is appropriate, and allows use thereof (step 358 ). On the other hand, if the detection point counter is equal to or smaller than the detection point threshold N ₂ , the parking assist system judges that the target space estimation result is not appropriate and does not allow employment thereof (step S4) 359 ). After determining whether or not to set the target space estimation result, the parking assist system sets the detection point counter to zero and initializes its status (steps 360 and 361 ).

By configuring the parking assist system as described above, the parking assist system sets the necessary number of obstacle detection points in accordance with the maximum vehicle speed or the minimum vehicle speed of the native vehicle while the native vehicle is traveling from the parking space detection start position to the parking space detection end position, and determines that the target space estimation result is not appropriate when the number of points that have been detected is less than the necessary number of detection points, so that the parking assistance system can schedule a guidance resulting from parking assistance if the parking assistance system can not identify the position of the destination and is unable to to accurately recognize the destination parking space, such as when the traveling speed of the native vehicle is fast and target detection accuracy is poor, and the parking assistance ystem can more reliably and safely prevent a situation where the native vehicle ends up being taken to a room not by the driver is intentional, and the native vehicle ends up touching an obstacle.

Embodiment 4

Hereinafter, other embodiments of the parking assist system of the present invention will be described with reference to the drawings. 13 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 4. FIG. In 13 the same reference numerals are given to portions that are the same as those, or correspond to those in FIG 1 , In 13 are the only sections that differ from 1 distinguish that there is no parking space detection position identification means 7 and there is a means of judging the appropriateness of an esteemed space 45 there are, and the other sections are completely the same as those in 1 so that a description thereof is omitted.

14 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 45 shows. In 14 first, the parking assist system compares the input Θ of the steering angle sensor with a neutral steering angle Θ ₀ (step 451 ). If the steering angle Θ of the native vehicle coincides with the neutral steering angle Θ ₀ , then the parking assist system calculates a difference V _D between a left wheel speed V _L and a right vehicle speed V _{R of} the native vehicle from the wheel speed sensor input (step 452 ). It is noted that in the present embodiment, the neutral steering angle θ _{0 is} adopted, but the steering angle condition is not limited thereto, and other steering angle conditions may be used. The parking assist system compares the calculated right-left wheel speed difference V _D with a threshold V _TH that is estimated (step 453 ), and when the right-left wheel speed difference V _{D is} smaller than the threshold V _TH , the parking assist system judges that the target space estimation result is appropriate, and sets this result (step 454 ). When the right-left wheel speed difference V _{D is} equal to or greater than the threshold V _TH , the parking assist system judges that the target space estimation result is not appropriate and does not allow use of this result (step 455 ).

By configuring the parking assist system as described above, the parking assist system determines that the target space estimation result is not appropriate when the right-left wheel speed difference of the native vehicle estimated from the steering angle of the native vehicle is greater than the actual right-left wheel speed difference, which is detected so that the parking assist system can terminate a guidance resulting from parking assistance when the parking assistance system is unable to accurately detect the position of the native vehicle, such as when the air pressure of either the left or right tire of the system's own Vehicle is low, and the parking assistance system can reliably and safely prevent a situation where the native vehicle ends up being led to a space that is not intended by the driver. According to the present embodiment, the parking assist system can be realized without having to add a configuration for detecting tire air pressures, so that an increase in cost can be avoided.

Embodiment 5

15 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 5. FIG. In 15 the same reference numerals are given to portions which are the same as those, or correspond to those in Embodiment 4. In 15 is the only section that is different from 13 distinguishes, the means for judging the appropriateness of an estimated space 55 , and the other sections are the same as those in 13 so that a description thereof is omitted. 16 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 55 shows. In 16 The parking assist system calculates differences in the X direction and the Y direction between the record of the corner shape of the obstacle that has been estimated and the record calculated from the distance detection result of the ultrasonic sensor (step 552 ). The parking assist system does this for the number of points sensed by the ultrasound sensor (step 553 ).

Based on the calculated obstacle position difference result, the parking assist system calculates standard deviations σ _x and σ _y in the X direction and the Y direction (steps 554 and 555 ). The parking assist system compares whether or not the calculated obstacle position difference standard deviation σ _{x is} smaller than a threshold value x _TH and the calculated obstacle position difference standard deviation σ _{y is} smaller than a threshold value y _TH (step 556 ), and if both are satisfied, the parking assist system judges that the target space estimation result is appropriate, and uses this result (step 557 ). If the calculated Obstacle position difference standard deviation σ _{x is} equal to or greater than the threshold value x _TH or the calculated obstacle position difference standard deviation σ _{y is} equal to or greater than the threshold value y _TH , the parking assist system further judges that the target space estimation result is inappropriate and does not allow employment of this result ( step 558 ). It is noted that, in the present embodiment, the parking assist system calculates variations in the shape of the obstacle estimated from the standard deviations in the differences of the record that was estimated and the record of the distance detection result, but the method of calculating the variations is not limited thereto and other methods may be used.

By configuring the parking assist system as described above, the parking assist system judges the appropriateness of the target space estimation result in accordance with the extent of variations between the obstacle estimation result and the distance detection result, resulting from the complexity of the shape of the obstacle, so that in a case where a vehicle whose detection points vary that is the goal, such as z. For example, a truck, when the parking assist system can not identify the position of the destination, it becomes difficult for the parking assistance system to accurately recognize the destination parking space, and the parking assist system can schedule a guidance resulting from parking assistance, and the parking assist system a situation where the native vehicle ends up being guided by a parking assist control to a space unintended by the driver or effectively preventing a situation where the native vehicle ends up touching an obstacle.

Embodiment 6

Hereinafter, other embodiments of the parking assist system of the present invention will be described with reference to the drawings. 17 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 6. FIG. In 17 the same reference numerals are given to sections that are the same as or correspond to those in FIG 13 , In 17 are the only sections that differ from 13 differ that the vehicle height sensing means 8th is added and it is a means of judging the appropriateness of an esteemed space 65 there are, and the other sections are completely the same as those in 13 so that a description thereof is omitted. 18 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 65 shows. In 18 The parking assist system detects the vehicle height of the native vehicle through a vehicle height sensor 8th (Step 651 ), uses the detected vehicle height as a vehicle height of the current period H and calculates a difference H _D therebetween and a vehicle height H _{0 of} the previous period (step 652 ). The parking assist system compares the calculated vehicle height difference H _D with a threshold H _TH (step 653 ), and when the vehicle height difference H _{D is} equal to or greater than the threshold value H _TH , the parking assist system adds 1 to a vehicle height _fluctuation counter N _H (step 654 ), and if the calculated vehicle height difference H _{D is} less than the threshold value H _TH , then the parking assist system sets the vehicle height fluctuation counter N _H to 0 (step 655 ).

In step 652 The parking assist system calculates the difference H _D between the vehicle height H of the current period and the vehicle height H _{0 of} the previous period, and the "vehicle height of the previous period" used in the next period becomes the vehicle height of the current period. For this reason, to the "vehicle height of the previous period H ₀ ", that in the step of the next period 652 as the vehicle height of the current period H is referenced in step 656 replaced and maintained the "vehicle height of the current period H" for the "vehicle height of the previous period H ₀ ".

When the vehicle _{height fluctuation counter} N _{H is} smaller than a threshold value N _HTH (step 657 ), the parking assist system judges that the target space estimation result is appropriate, and uses this result (step 658 ). Further, when the vehicle height fluctuation counter N _{H is} equal to or greater than the threshold value N _HTH , the parking assist system judges that the target space estimation result is not appropriate and does not allow use of this result (step 659 ).

By configuring the parking assist system as described above, the parking assist system detects the vehicle height of the native vehicle and determines that the target space estimation result is not appropriate when the amplitude of the fluctuation in the vehicle height is equal to or greater than a predetermined value, so that situations no longer occur where e.g. For example, as the native vehicle travels in a location where the unevenness in the road surface is significant and the vehicle height changes, the result of space detection is affected and changes, as a result of which it becomes difficult for the parking assistance system, the target parking space is accurate recognize, and that native vehicle ends up being guided by parking assist control to a space unintended by the driver, and the native vehicle ends up touching an obstacle.

Embodiment 7

This embodiment 7 is a modification of Embodiment 6, and one where the parking assist system is configured is the appropriateness of an estimated space based on the front-to-rear direction of the native vehicle or the right-left direction of the native vehicle or the entire vehicle height of the native vehicle. It will only be the flow chart of 19 which shows the processing sequence of processing for judging the adequacy of an estimated space. The parking assist system receives, from the input of the vehicle height sensor 8th , a front left vehicle height H _FL , a front right vehicle height H _FR , a rear left vehicle height H _RL and a rear right vehicle height H _{RR of} the native vehicle (steps 751 to 754 ).

When the absolute value of the difference between the front left vehicle height H _FL and the rear left vehicle height H _{RL of} the native vehicle is less than a threshold H ₁ and the absolute value of the difference between the front right vehicle height H _FR and the rear right vehicle height H _{RR of} the native Vehicle is less than a threshold H ₂ (step 755 ), and when the absolute value of the difference between the front-left vehicle height H _FL and the front-right vehicle height H _{FR of} the native vehicle is smaller than a threshold H ₃ and the absolute value of the difference between the rear-left vehicle height H _RL and the rear-right vehicle height H _{RR of} the native vehicle is less than a threshold H ₄ (step 756 Also, if the front left vehicle height H _FL and the front right vehicle height H _FR and the rear left vehicle height H _RL and the rear right vehicle height H _{RR of} the vehicle are greater than a threshold H ₅ and smaller than a threshold H ₆ ( step 757 ), the parking assist system judges that the target space estimation result is appropriate, and uses this result (step 758 ). Further, if any one of the aforementioned conditions is not established, the parking assist system judges that the target space estimation result is not appropriate and does not allow use of this result (step 759 ).

By configuring the parking assist system as described above, the parking assist system detects the vehicle height of the native vehicle and determines that the target space estimation result is not appropriate if the front-rear or right-left vehicle height difference is equal to or greater than a predetermined value or if the vehicle height is equal to or greater than is smaller than a predetermined value or equal to or greater than a predetermined value, so that although situations are assumed where z. For example, if the vehicle height in the front-rear or right-left direction tends to be due to the load state of the native vehicle, or the vehicle height of the native vehicle changes, the result of space detection is influenced and changed as a result of it the parking assist system becomes difficult to accurately recognize the target parking space and the native vehicle ends up being guided by parking assist control to a space unintended by the driver and the native vehicle ends up touching an obstacle by using the present one Method, the parking assistance system can effectively prevent such situations.

Embodiment 8

Hereinafter, another embodiment of the parking assist system of the present invention will be described with reference to the drawings. 20 FIG. 10 is a block diagram showing the processing configuration of a parking assist system in Embodiment 8. FIG. In 20 the same reference numerals are given in sections that are the same as those or correspond to those in FIG 13 , In 20 are the only sections that differ from 13 distinguish that the tire air pressure detecting means 9 is added and it is a means of judging the appropriateness of an esteemed space 85 there are, and the other sections are completely the same as those in 13 so that a description thereof is omitted. 21 FIG. 12 is a flowchart showing the processing sequence of the estimated space estimation processing. FIG 85 shows.

In 21 receives the parking assist system, from the input of tire air pressure sensors, a front left tire inflation pressure P _FL , a front right tire inflation pressure P _FR , a rear left tire inflation pressure P _RL and a rear right tire inflation pressure P _{RR of} the native vehicle (steps 851 to 854 ). When the front left tire air pressure P _{FL is} smaller than a threshold P _TH and the front right tire air pressure P _{FR is} smaller than the threshold P _TH and the rear left tire air pressure P _{RL is} smaller than the threshold P _TH and the rear right tire air pressure P _{RR is} smaller as the threshold P _TH (step 855 ), the parking assist system judges that the target space estimation result is appropriate, and uses this result (step 856 ). When the front-left tire inflation pressure P _{FL is} equal to or greater than the threshold P _TH , or when the front-right tire inflation pressure P _{FR is} equal to or greater than the threshold P _TH , or when the rear-left tire inflation pressure P _{RL is} equal to or greater than the threshold P _TH or if the rear right tire inflation pressure P _{RR is} equal to or greater than the threshold value P _TH , then the parking assist system judges that the target space estimation result is not appropriate and does not allow use of this result (step 857 ). It should be noted that, in the present embodiment, the parking assist system makes a determination based on the tire air pressures of the four wheels of the native vehicle, but the parking assist system may be configured not to use all four wheels.

By configuring the parking assist system as described above, the parking assist system detects the tire air pressures of the native vehicle and determines that the target space estimation result is not appropriate when the air pressure of any of the tires used in the own vehicle position estimation is equal to or less than a predetermined value, so although situations are assumed where z. B. the air pressure of any of the tires is low and the parking assistance system can not accurately recognize the position of the native vehicle and the native vehicle ends up being guided by parking assistance control to a space that is not intended by the driver, by using the present method the parking assistance system can effectively prevent such situations.

Various modifications and changes of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention, and it should be understood that this is not limited to the illustrative embodiments set forth herein.

Claims (9)

A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or that promotes entry into the target parking space, characterized by parking space detection position identification means ( 7 ) setting a parking space detection start position and end position on the basis of at least the output of the own vehicle position estimating means, and means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimation means; where the means of guided assistance ( 6 ) instructs the target parking space estimation result based on the outputs of the estimated space appropriateness estimating means and the target space estimating means, or assists entry into the target parking space. A parking assist system according to claim 1, characterized in that the means for judging the appropriateness of the output of the target estimation means calculates a standard deviation of an average steering angle of the native vehicle while the native vehicle is traveling a distance from the parking space detection start position to the parking space detection end position, and if the standard deviation is equal to or is greater than a predetermined value, determines that the output of the target space estimation means is inappropriate and notifies the driver by the means of guided assistance that the target parking space can not be identified. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or that promotes entry into the target parking space, characterized by parking space detection position identification means ( 7 ) setting a parking space acquisition start position and end position based on at least the output of the own vehicle position estimation means; and a means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimation means that sets a necessary number of obstacle detection points N ₁ in accordance with a vehicle speed average between the home-car parking space detection start position and the parking space detection end position, and if the number of detection points detected by the distance detection means For example, while the native vehicle is traveling from the parking space acquisition start position to the parking space acquisition end position smaller than the necessary number of detection points N _{1, it} is determined that the output of the target space estimation means is inappropriate and informs the driver by the means of guided assistance that the target parking space is not identified can be. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or that promotes entry into the target parking space, characterized by parking space detection position identification means ( 7 ) setting a parking space detection start position and end position on the basis of at least the output of the own vehicle position estimating means, means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimating means which sets a necessary number of obstacle detection points N ₂ in accordance with a maximum vehicle speed or a minimum vehicle speed between the home-car parking space detection start position and the parking space detection end position, and if the number of detection points, which is detected by the distance detecting means while the native vehicle is traveling from the parking space detection start position to the parking space detection end position is smaller than the necessary number of detection points N ₂ , determines that the output of the target space estimation means is not appropriate and notifies the driver by the means of guided assistance, that the destination parking space can not be identified. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ), which is a position and a corner shape of an obstacle with respect to the position of the native vehicle estimates based on the outputs of the own vehicle position estimation means and the distance detection means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or supports entry into the target parking space; characterized by a means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimating means which determines when an actually detected right-left wheel speed difference is greater than a right-left wheel speed difference of the native vehicle estimated from a steering angle of the native vehicle in the own vehicle position estimating means in that the output of the target space estimation means is inappropriate and informs the driver, by the means of guided assistance, that the target parking space can not be identified. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or supports entry into the target parking space; characterized by a means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimation means, the means guided assistance to the driver, the appropriateness of the output of the target space estimation means in accordance with the extent of variations between the output of the obstacle estimation means and the output of the distance detection means resulting from the complexity of the shape of the obstacle come, reports. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or supports entry into the target parking space; characterized by a vehicle height detecting means ( 8th ) that detects a vehicle height of the native vehicle; and a means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimating means which determines that the output of the target space estimating means is inappropriate when an amplitude of a fluctuation in the vehicle height of the native vehicle is equal to or greater than a predetermined value in the vehicle height detecting means and the driver by the means guided assistance instructs that the target parking space can not be identified. The parking assistance system according to claim 7, characterized in that the means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimating means when a front-to-rear vehicle height difference of the native vehicle is equal to or higher than a predetermined value H ₃ or when a right-left vehicle height difference of the native vehicle is equal to or higher than a predetermined value H ₄ or if a vehicle height of the system's own vehicle H is equal to or less than a predetermined value ₅ or equal to or greater than a predetermined value H ₆ is in the vehicle height detecting means that the output of the target area estimation means is not appropriate, and instructs the driver guided by the central support that the Target parking space can not be identified. A parking assist system installed in a vehicle, the parking assist system comprising: an own vehicle position estimation means ( 1 ) which estimates a position and a moving direction of the native vehicle; a distance detection means ( 2 ) that detects an obstacle around the native vehicle; an obstacle estimator ( 3 ) estimating a position and a corner shape of an obstacle with respect to the position of the native vehicle on the basis of the outputs of the own vehicle position estimating means and the distance detecting means; a target space estimation means ( 4 ) that estimates a position of a target parking space based on the output of the obstacle estimation means; a means of assisting ( 6 ) that instructs the target parking space estimation result or that promotes entry into the target parking space, characterized by a tire air pressure detecting means ( 9 ) detecting tire air pressures of the native vehicle and a means ( 5 . 25 . 35 . 45 . 55 . 65 . 75 . 85 ) for judging the appropriateness of the output of the target space estimating means that determines that the output of the target space estimating means is not appropriate when the air pressure of any tire used by the own vehicle position estimating means is equal to or smaller than a predetermined value P in the tire air pressure Detection means, and instructs the driver through the means guided assistance that the target parking space can not be identified.

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