JP2002154396A - Parking support device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an adequate layout drawing of surrounding objects by discriminating a fixed structure of wall, fence, etc., in a parking lot and a parking vehicle. SOLUTION: This parking supporter device comprises a reflected wave observation means 1a emitting an optical or electromagnetic or acoustic wave to observe a reflected wave from an object, a distance detection means 1b detecting a distance to the object based on a radiant and reflected wave, a classification decision means 3a deciding classification of the object based on intensity of the reflected wave and the object distance, a reference line detection means 3b detecting a reference line representing an object having low possibility of movement based on the object distance and the object classification, a vehicle movement detection means 2 detecting movement of a vehicle, and a layout drawing making means 3c for making an object layout drawing in the surrounding of the vehicle based on the vehicle movement and the object distance on the basis of the reference line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for assisting a driver in a parking operation when parking a vehicle.

[0002]

2. Description of the Related Art At the time of parking, a surrounding object layout diagram showing the layout of obstacles and the like around a vehicle is created based on distance measurement data measured by an ultrasonic sensor or a radar, and whether parking is possible is notified by an image and a voice. Such a vehicle parking assist device is known (for example, Japanese Patent Application Laid-Open No. 09-180).
No. 100).

[0003]

However, in the conventional vehicle parking assist system, the surrounding object layout is created only by plotting distance data measured while traveling or expressing the distance data by a line segment. It is not possible to distinguish between a fixed structure such as a wall and a fence and a parked vehicle, and it is not possible to create an appropriate surrounding object layout diagram, so that sufficient parking support may not be provided.

It is an object of the present invention to identify a fixed structure such as a wall or a fence of a parking lot and a parked vehicle and create an appropriate surrounding object layout diagram.

[0005]

Means for Solving the Problems The present invention will be described with reference to FIGS. 1 and 3 showing the configuration of an embodiment. (1) The invention of claim 1 is based on a layout of objects around a vehicle. Applied to a vehicle parking assist device that assists the driver in parking operation, emits light, electromagnetic waves, or sound waves, and observes reflected waves from an object, based on the reflected waves and the reflected waves. Distance detecting means 1b for detecting a distance to an object, a type determining means 3a for determining the type of an object around the vehicle based on the intensity of the reflected wave and the object distance, and the object distance and the object type. Reference line detection means 3b for detecting a reference line representing an object that is unlikely to move based on the vehicle, vehicle movement detection means 2 for detecting the movement of the vehicle, and the vehicle movement and the object distance based on the reference line. And based on the vehicle circumference A layout creating means 3c for creating an object layout of, thereby achieving the above object. (2) The type determining means 3a of the vehicle parking assist device according to claim 2 stores the statistical means 21 for calculating the statistics of the reflected wave intensity and the object distance, and the reference statistic for the type determination. Storage means 23; comparing means 22 for comparing the calculated value of the statistic with the reference statistic to determine the type of the object;
It is determined whether the object around the vehicle is an object that is unlikely to move or an object that is likely to move. (3) According to a third aspect of the present invention, in the vehicle parking assist apparatus, the type of the object is determined by the type determining means 3a based on the change pattern of the statistic. (4) The type determining means 3a of the vehicle parking assist device according to claim 4 determines that the object having the uniform object distance and the reflected wave intensity is a concrete wall or a block wall. (5) The type determination means 3a of the vehicle parking assist device according to claim 5, wherein the reflected wave intensity is strong and its variance is large, and further, the reflected wave intensity and its variance are repeatedly parked in an object. Is determined.

In the section of the means for solving the above-described problem, a diagram of one embodiment is used for easy understanding of the description, but the present invention is not limited to this embodiment. .

[0007]

(1) According to the first aspect of the present invention, an object that is unlikely to move, that is, a fixed structure such as a wall, and an object that is likely to move, such as a parked vehicle, from objects around the vehicle. And a layout drawing of a parked vehicle or the like can be appropriately created based on a reference line of a fixed structure such as a wall. Then, appropriate support can be performed according to the type of the surrounding object such as a wall or a parked vehicle. (2) According to the second aspect of the present invention, it is possible to more accurately identify an object having a low possibility of moving and an object having a possibility of moving. (3) According to the third aspect of the present invention, an object in which the reflected wave intensity and its variance value form a repetitive pattern, such as a fence composed of a pillar portion and a wire mesh portion, or a vehicle parked along a parking row, can accurately detect an object. Can be identified. (4) According to the invention of claim 4, a concrete wall or a block wall of a parking lot can be accurately identified. (5) According to the invention of claim 5, the parked vehicle can be identified accurately.

[0008]

FIG. 1 is a diagram showing the configuration of an embodiment. As shown in FIG. 2, the distance measuring sensor 1 is attached to a front portion and a rear portion of the own vehicle 11, and is provided between an object existing laterally or obliquely forward of the front portion of the own vehicle and an object existing laterally or obliquely behind the rear portion of the own vehicle. Detect distance. Although FIG. 1 shows only one of the two distance sensors installed at the front and rear of the vehicle, the other distance sensor has a similar configuration and function. 2, 12 and 13 are parked vehicles,
14 is a wall of a parking lot.

The distance measuring sensor 1 has a reflected wave observation section 1a and a distance detection section 1b. The reflected wave observation unit 1a observes reflected waves from an object such as light, electromagnetic waves, and sound waves emitted toward the periphery of the vehicle, and outputs the intensity of the reflected waves. The distance detector 1b detects the distance to the object based on the phase difference between the radiation wave and the reflected wave. A laser beam, an electromagnetic wave, an ultrasonic wave, or the like can be used for the distance measuring sensor 1. By performing distance measurement while moving the vehicle with the distance measurement sensor 1, distance measurement data similar to that of a sensor having a scanning mechanism can be obtained.

The vehicle movement detection sensor 2 detects the amount of movement of the own vehicle per unit time and the direction of travel, and integrates these detected values to detect the relative position of the own vehicle from the departure point. The vehicle movement detection sensor 2 includes a movement amount detection unit 2a and a traveling direction detection unit 2b. The movement amount detection unit 2a detects the movement amount by measuring the number of pulses generated by a pulse generator that rotates in conjunction with the wheels. Heading detector 2b
Detects the steering direction by measuring the steering angle of the steering. The method of detecting the moving amount and the traveling direction of the vehicle is not limited to the detection method of this embodiment. For example, even if the moving amount and the traveling direction are detected by measuring the rotation pulses of the left and right wheels and the difference between them. Good.

The microcomputer 3 includes a CP (not shown).
U, ROM, RAM, and the like, and constitutes a type determination unit 3a, a reference line detection unit 3b, and a surrounding object arrangement diagram creation unit 3c in software form. The type determination unit 3a determines the type of the object around the vehicle, that is, the possibility of moving based on the reflected wave intensity from the object measured by the reflected wave observation unit 1a and the distance to the object detected by the distance detection unit 1b. A low object and an object that may move are determined. Objects that are unlikely to move include fixed structures such as walls, and objects that may move include parked vehicles. The method of determining this type will be described later.

The reference line detection unit 3b detects a reference line representing a fixed structure that is unlikely to move based on the type determination result by the type determination unit 3a and the distance detection value by the distance detection unit 1b. For example, in the parking lot shown in FIG. 2, the wall 14 of the parking lot is a fixed structure that is unlikely to move, and serves as a reference for the arrangement of objects that may move, such as the parked vehicles 12 and 13. When the host vehicle attempts to park, the reference line is detected and a line segment representing the surface of the wall 14 is detected as a reference line.

The surrounding object layout drawing creating section 3c is based on the reference line detected by the reference line detecting section 3b and the distance data to an object such as a parked vehicle which may be moved and detected by the distance detecting section 1b. Surrounding objects are arranged in a virtual space, and their arrangement is projected on a surface corresponding to the ground surface to create a surrounding object arrangement diagram. The surrounding object layout is displayed on the display 4 to provide a guidance broadcast through the speaker 5, and the vehicle control device 6 is controlled based on the surrounding object layout to support the parking operation. Vehicle control device 6
Controls the driving force and braking force of the vehicle by adjusting the throttle valve opening of the engine, the gear ratio of the transmission, and the hydraulic pressure of the brake.

The determination method by the type determination unit 3a will be described. The type determination unit 3a includes a statistical processing operation device 21, databases 22, 23, and a comparison device 24, as shown in FIG. The statistical processing operation device 21 calculates one set of measurement values in a range where the distance detected by the distance detection unit 1b is substantially continuous on a straight line and the reflected wave intensity detected by the reflected wave observation unit 1a is stationary. The average value and the variance value of the reflected wave intensity of each set of measured values and the variance value of the distance are statistically calculated. And
The comparison device 22 compares the average value and the variance value of the reflection intensity and the distance with the past determination reference statistics stored in the database 23 to determine the type of the reflection object. The database 23 may be constructed in advance by experiment,
A learning type in which data measured by the own vehicle is added while verifying the data may be used.

Note that, although the detection distance is substantially continuous on a straight line, in a region divided into a plurality of groups due to a change in reflected wave intensity, the average value and the variance value of the reflected wave intensity in each group are determined. When regularity is found in the state of the change, the type of the object is determined by collating with the criterion statistic stored in the database 23.

A specific example of the type determination will be described. As fixed structures that are unlikely to move, concrete walls, block walls, fences, plants, fences, and the like are assumed.
FIG. 4 shows observation waveforms of these fixed structures that are unlikely to move. Fig. 4 (a)
As shown in FIG. 7, both the distance and the measured value of the reflected wave intensity are uniform. On the other hand, as shown in FIG. 4 (b), the fence and the plant have a weak reflected wave intensity and a large dispersion. Also, the variance of the distance detection values becomes relatively large. Furthermore, since the fence has a repeating pattern of metal pillars and wire mesh, FIG.
As shown in (c), the reflected wave intensity is strong in the column portion and the dispersion value is small, but the reflected wave intensity is weak in the wire mesh portion.

FIG. 5 shows an observed waveform of a parked vehicle that may move. A parked vehicle that is likely to move has a high reflected wave intensity, and the variance of the reflected wave intensity is large according to the change in the components. In addition, due to the repetition of the parking queue, a constant repetition pattern is generated in the reflected wave intensity and its dispersion.

Next, the processing of the reference line detecting unit 3b and the surrounding object layout drawing creating unit 3c will be described. Set a coordinate system based on the ground plane or a coordinate system based on your vehicle,
By plotting the position of the vehicle detected by the vehicle movement detection sensor 2 and the distance to the surrounding object detected by the distance sensor 1 in the coordinate system, the positional relationship between the vehicle and the surrounding object can be grasped. . These surrounding objects are arranged in a virtual space so that the type determination unit 3a can distinguish between an object such as a wall that is unlikely to move and an object such as a parked vehicle that may move. Among these objects, a straight line including a line segment constituting an object determined to be a fixed structure that is unlikely to move is set as a reference line.

Here, when the parking operation of the driver is analyzed,
It can be seen that the process of (1) searching and selecting a parking place, (2) planning an approach route to the parking place, and (3) moving to the parking place along the approach route, forward and backward and steering are repeated. By doing so, the same object may be repeatedly detected several times. At this time, the same object may be detected at different positions due to a position detection error of the vehicle or the like. Further, when the object is a vehicle or the like, a different detection value is obtained when the vehicle moves or the door is opened and closed. If a wall surface is detected at a slightly different position from the wall surface forming the reference line or the wall surface whose positional relationship with the reference line is determined, it is regarded as a deviation resulting from an error due to position detection, and The position of the object detected before and after is corrected.

By using the spatial layout obtained in this manner, when the object around the vehicle is a fixed structure such as a wall, it is safe to approach a very short distance based on the measurement result. Is notified to the driver, and when an object around the vehicle is a parked vehicle, the driver may start to move, so that the driver is alerted. Further, in calculating the approach route to the parking place, a parked vehicle stopped at an angle to the parking place will not be mistaken for a fixed structure such as a wall, and an appropriate route to the parking place will be calculated. Can be.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment.

FIG. 2 is a diagram showing an installation location of a distance measuring sensor.

FIG. 3 is a diagram illustrating a configuration of a type determination unit.

FIG. 4 is a diagram illustrating measurement results of a distance and a reflected wave intensity with respect to a fixed object that is unlikely to move.

FIG. 5 is a diagram illustrating measurement results of a distance and a reflected wave intensity with respect to a parked vehicle that may move.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 distance sensor 1a reflected wave observation unit 1b distance detection unit 2 vehicle movement detection sensor 2a movement amount detection unit 2b traveling direction detection unit 3 microcomputer 3a type determination unit 3b reference line detection unit 3c surrounding object arrangement diagram creation unit 4 display 5 speaker 6 Vehicle control device

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Claims (5)

[Claims] A parking assist system for a vehicle that assists a driver in a parking operation based on a layout of an object around a vehicle, wherein the reflected wave observing means emits light, electromagnetic waves, or sound waves and observes reflected waves from the object. A distance detection unit that detects a distance to an object based on the radiation wave and the reflected wave, a type determination unit that determines a type of an object around the vehicle based on the intensity of the reflected wave and the object distance, A reference line detection unit that detects a reference line representing an object that is unlikely to move based on the object distance and the object type; a vehicle movement detection unit that detects a movement of a vehicle; and A parking assist system for a vehicle, comprising: a layout drawing creating unit that creates an object layout around a vehicle based on a vehicle movement and the object distance. 2. The parking assist system for a vehicle according to claim 1, wherein the type determination unit calculates a statistic of the reflected wave intensity and the object distance, and a reference statistic for type determination. And a comparing means for comparing the calculated value of the statistic with the reference statistic to determine the type of the object, wherein the object around the vehicle is less likely to move or moves. A parking assistance device for a vehicle, which determines whether the object is a potential object. 3. The parking assist system for a vehicle according to claim 2, wherein the type determining means determines the type of the object based on the change pattern of the statistic. 4. The parking assist system for a vehicle according to claim 3, wherein the type determining means determines that the object having the uniform object distance and the reflected wave intensity is a concrete wall or a block wall. A parking assist device for a vehicle, comprising: 5. The parking assist system for a vehicle according to claim 3, wherein the type determining means has a strong reflected wave intensity and a large variance, and further, the reflected wave intensity and the variance form a repetitive pattern. A vehicular parking assist device, wherein an object is determined to be a parked vehicle.