JP2003312412A - Parking support device and automatic steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking support device for properly moving a vehicle even when there is a change in a road surface gradient up to a target position from one's own vehicle position. <P>SOLUTION: This parking support device 1 calculates a target parking position on the basis of an image imaged by a CCD camera 13 in a parking support ECU 2. A road surface gradient detecting means 14 detects the road surface gradient between the one's own vehicle position and the target parking position, and corrects the target parking position on the basis of a variation in the road surface gradient when there is a change in the road surface gradient. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a parking assist device and an automatic steering device.

[0002]

2. Description of the Related Art When driving an automobile, it is relatively difficult to park the vehicle in a garage or in parallel parking. Particularly, beginners are often not good at driving when parking. Therefore, an automatic steering device in a parking assistance device for assisting a driving operation during parking is known. As an automatic steering device of this type, a conventional automatic steering device is disclosed in, for example, Japanese Patent Laid-Open No. 11-20849.
There is an automatic vehicle steering system disclosed in Japanese Patent No. This automatic steering device determines a locus of movement to a target position where the vehicle is stopped, detects the load state of the wheels, and corrects the locus of movement of the vehicle according to the detected load state of the wheels. Since the automatic steering device detects the load state of the wheels, it is possible to move the vehicle to an appropriate target position even if the vehicle is stopped on an inclined road surface or the vehicle itself leans. it can.

[0003]

However, in the conventional automatic steering device disclosed in the above publication, it is possible to reduce the deviation from the planned route due to the geometry change of the suspension system when traveling on the inclined road surface. However, it is not possible to correct the deviation of the setting of the target route and the target parking position itself.

Here, for example, when the target parking position is set based on a two-dimensional image, if there is a change in the road surface gradient between the own vehicle and the target parking position, the target route obtained by calculation and the actual The distance of the three-dimensional path is different. Therefore, there is a problem that the target route recognized by the automatic steering device and the actual route are deviated from each other, and the vehicle cannot be reliably moved.

Also, when setting the target parking position in the parking assist device, if there is a change in the road surface gradient between the own vehicle position and the target parking position, the target parking position will be displaced and the parking position will be set appropriately. There was a problem that the vehicle could not be guided.

Therefore, an object of the present invention is to provide a parking assist device and an automatic steering device capable of appropriately moving a vehicle even when there is a change in the road surface gradient from the vehicle position to the target position. It is in.

[0007]

A parking assistance device according to the present invention, which has solved the above-mentioned problems, is based on two-dimensional image information.
In a parking assistance device that includes a parking assistance control device that calculates a target parking position at which a vehicle parks and that assists the vehicle to park at the target parking position calculated by the parking assistance control device, the road surface gradient of the road surface on which the vehicle moves is calculated. The parking assistance control device is provided with a road surface gradient detecting means for detecting, and the parking assist control device corrects the target parking position in accordance with a change in the road surface gradient detected by the road surface gradient detecting means.

As described above, in the parking assistance apparatus according to the present invention, when the target parking position is set in the parking assistance apparatus, the road surface gradient is detected by the road surface gradient detecting means, and based on the change in the detected road surface gradient. Correct the target parking position. Therefore, it is possible to set the target parking position based on the two-dimensional image and set the target parking position at an appropriate position even when there is a road gradient between the own vehicle position and the target parking position.

[0009] Here, it is preferable that the parking assist control device terminates the parking assist when the change in the road surface slope detected by the road surface slope detecting means becomes equal to or larger than a predetermined threshold value. .

Alternatively, the parking assistance control device may be configured to prohibit the start of parking assistance when the change in the road surface gradient detected by the road surface gradient detecting means becomes equal to or more than a predetermined threshold value.

If the road surface gradient between the vehicle position and the target parking position is too large, for example ± 3 degrees or more,
The correction amount may become too large and exceed the allowable range of calculation in the parking assist device. In such a case, in order to safely stop the parking assistance, the present invention stops the parking assistance or prohibits the start of the parking assistance when the change of the road surface slope exceeds a predetermined threshold value. ing. By providing such a threshold value, parking assistance can be performed safely.

The automatic steering system according to the present invention, which has solved the above-mentioned problems, includes an automatic steering control device for obtaining a target route to a target position where a vehicle is parked based on two-dimensional image information, and an automatic steering control device. In an automatic steering device including an automatic steering actuator that moves a vehicle according to a calculated target route, the automatic steering control device includes a road surface gradient detection unit that detects a change in road surface gradient of a road surface on which the vehicle moves. The target route is corrected according to the change of the road surface gradient detected by the road surface gradient detecting means.

In the automatic steering apparatus according to the present invention, when the target route between the own vehicle position and the target parking position is set, the road surface gradient detecting means detects the road surface gradient on the target route, and changes in the road surface gradient are detected. The target route is corrected accordingly. Therefore, even if there is a road surface gradient between the own vehicle position and the target parking position, the target route can be set appropriately.

It is preferable that the automatic steering control device terminates the automatic steering when the change of the road surface slope detected by the road surface slope detecting means becomes a predetermined threshold value or more. .

Alternatively, the automatic steering control device may have a mode in which the start of the automatic steering is prohibited when the change in the road surface gradient detected by the road surface gradient detecting means exceeds a predetermined threshold value.

Also in the automatic steering apparatus according to the present invention, if the road surface gradient is too large, the correction amount may become too large, and the allowable range of calculation may be exceeded. Therefore, a predetermined threshold value is set for the change of the road surface gradient, and when the threshold value is exceeded, the automatic steering is stopped or the start of the automatic steering is prohibited. Thus, by setting a threshold value for the change of the road surface gradient and stopping the automatic steering or prohibiting the start of the automatic steering by the threshold value, the automatic steering can be safely performed.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a parking assistance device according to an embodiment of the present invention.

As shown in FIG. 1, a parking assistance device 1 according to the present embodiment is mounted on a vehicle and provides parking assistance when the vehicle is parked. This parking assistance device 1
The electronic control unit includes a parking assist ECU 2 and an automatic steering device 3. The parking assist ECU 2 controls the entire parking assist device 1, and includes a CPU, a ROM, and an RA.
M, an input signal circuit, an output signal circuit, a power supply circuit, etc., and stores various control routines including a parking assist control routine.

The parking assist ECU 2 includes a vehicle speed sensor 11,
A steering angle sensor 12, a CCD camera 13 for acquiring two-dimensional image information, and a road surface gradient detecting means 14 including, for example, an acceleration sensor are connected.

The vehicle speed sensor 11 is attached to, for example, a wheel (not shown) of the vehicle, detects the rotational speed of the wheel, and outputs a speed signal to the parking assist ECU 2. The parking assist ECU 2 calculates the traveling distance of the vehicle based on the speed signal output from the vehicle speed sensor 11. The steering angle sensor 12 is attached to, for example, a steering shaft (not shown) of the vehicle, detects a rotation angle of the steering wheel, and outputs an angle signal to the parking assist ECU 2 as a rotation angle signal. The parking assist ECU 2 calculates the turning angle of the steered wheels based on the detected steering rotation angle signal.

The CCD camera 13 is a camera provided with, for example, a wide-angle lens, which is arranged at a rear portion or a side portion of the vehicle, and is an image of a rear portion outside the vehicle.
The CCD camera 13 may be constantly imaging the rear of the vehicle, or may start imaging when the vehicle moves rearward to reduce power consumption. The backward movement of the vehicle can be detected, for example, by the shift lever entering the reverse range.

The road surface slope detecting means 14 is attached to, for example, a wheel of a vehicle (not shown), detects the rotational acceleration of the wheel, and outputs an acceleration signal to the parking assist ECU 2. The parking assist ECU 2 detects the cosine component θ of the gravitational acceleration from the difference between the acceleration signal output from the vehicle speed sensor 11 and the acceleration that should be given by driving the wheels. This cosine component θ is detected as the slope of the road surface.

Further, the parking assist ECU 2 has a monitor 15
The speaker 16 and the automatic steering actuator 17 are connected to each other.

The monitor 15 is installed in, for example, an instrument panel in the passenger compartment, and is arranged at a position where the driver's view can reach. This monitor 15 has a CCD
In addition to the image captured by the camera 13, a target parking frame indicating the target parking position displayed at the position calculated by the parking assist ECU 2, a pole that serves as a mark when avoiding obstacles, and the like are displayed. The speaker 16 is built in, for example, inside the front door in the vehicle interior, and the parking assist ECU 2
The information is presented to the driver or the like by voice based on the command of.

The automatic steering actuator 17 is connected to a wheel cylinder of a hydraulic brake (not shown) arranged on each wheel of the vehicle. Then, the braking force of the vehicle is adjusted by adjusting the brake hydraulic pressure based on a command from the parking assist ECU 2. The automatic steering actuator 17 is also connected to a steering rod (not shown) of the vehicle. Then, based on a command from the parking assist ECU 2, the steering rod is rotated so that the steered wheels have a predetermined steering angle.

Further, the parking assist ECU 2 is provided with a steering control section 21 which is an automatic steering control device of the present invention. The steering control unit 21 calculates the movement locus of the vehicle, which is the target route of the present invention, based on the positional relationship between the target parking position calculated in the parking assist ECU 2 and the current own vehicle position. The automatic steering actuator 17 is operated so that the vehicle moves according to the movement locus. In the present embodiment, the automatic steering device 3 includes a steering control unit 21 and an automatic steering actuator 17.

Next, the operation of the parking assist system according to this embodiment will be described.

FIG. 2 is a flowchart of the operation of the parking assistance device according to this embodiment.

When the driver puts the shift lever in the reverse range, the parking assistance control for performing the parking assistance is started. When the shift lever enters the reverse range, CC
The D camera 13 is turned on, a rear image around the vehicle is captured, and the image captured by the CCD camera 13 is displayed on the monitor 15. On the monitor 15, in addition to the image captured by the CCD camera 13, the target parking position is displayed at a predetermined default position, and an arrow for moving the target parking position is displayed. The driver sets the target parking position at a desired position in the monitor 15 without operating or operating the arrow as appropriate (S1). After setting the target parking position, the parking assist ECU 2
The positional relationship between the vehicle position and the target parking position is calculated based on the image captured by the camera. Then, the steering control unit 21
Then, the movement locus from the own vehicle position to the target parking position is calculated from the relationship between the own vehicle position and the target parking position (S2).

After the movement locus is calculated, it is determined from the road surface gradient θ detected by the road surface gradient detecting means 14 whether or not the road surface gradient has changed, that is, whether or not the road surface gradient change is 0 (S3). As a result, when it is determined in step S3 that the road surface gradient change is not 0, the target parking position is corrected based on the road surface gradient change (S4). Now, the target parking position is calculated by an appropriate method based on the two-dimensional image taken by the CCD camera 13. Therefore, if there is a road surface gradient change between the loci of movement of the vehicle, a deviation occurs in the target parking position, as shown in FIG. For example,
If the target parking position set when the CCD camera 13 picks up the image is point A, if the parking assist ECU 2 (FIG. 1) mounted on the vehicle C does not consider this road surface gradient change, the point B is the target. It is set as the parking position and deviates from the actual target parking position. For this reason,
When the road gradient detection means 14 detects a road gradient change, the parking assist ECU 2 corrects the target parking position based on the change amount of the road gradient change. The correction amount of the target parking position due to the change in the road surface gradient can be set according to the map shown in FIG. 4, for example.

For example, assume that the road surface gradient change amount Δθ becomes positive when the road surface is descending. Here, when the road surface gradient change amount Δθ is positive, the destination to which the vehicle C moves is a downhill, and therefore the actual target parking position is a position farther than the calculated target parking position. Therefore,
When Δθ is positive, the target parking position is corrected to be farther. Further, in a region where Δθ is positive, the deviation between the calculated target parking position and the actual target parking position becomes larger as Δθ becomes larger. Therefore, it is preferable that the correction amount of the target parking position with respect to the road surface gradient change amount is set so as to be large as a quadratic function, for example.

On the other hand, when Δθ is negative, the destination of the vehicle C is an uphill road, so the actual target parking position is closer to the calculated target parking position.
Therefore, when Δθ is negative, the target parking position is corrected to be closer. Further, in the region where Δθ is negative, the difference between the calculated target parking position and the actual target parking position is Δθ
Becomes smaller, becomes larger. For this reason, it is preferable to set the correction amount of the movement locus with respect to the road surface gradient change amount so as to become, for example, a quadratic function.

The corrected target parking position is calculated by adding the correction amount obtained based on the map shown in FIG. 4 to the preset target parking position. In this way, after the target parking position is corrected based on the road surface gradient change, the process returns to step S2, the movement locus is calculated based on the own vehicle position and the target parking position, and the road surface gradient change is 0 in step S3. Or not.

When it is determined in step S3 that the change in road gradient is 0, the vehicle is moved according to the movement trajectory calculated by the parking assist ECU 2.
The automatic steering actuator 17 is driven by the steering control unit 21 to execute automatic steering (S5). The automatic steering is performed while monitoring the vehicle speed of the vehicle detected by the vehicle speed sensor 11 and the steering angle calculated by the steering angle sensor 12.
While the automatic steering is being performed, the speaker 16 outputs, for example, a voice alerting the driver.

After the automatic steering is executed, it is detected whether or not the vehicle has reached the target parking position (S6). As a result, if it is determined that the target parking position has not been reached, the process returns to step S3 to detect a change in the road surface gradient, and thereafter, the same routine as the above routine is repeated. On the other hand, when it is determined that the vehicle has reached the target parking position, the parking assistance is ended and the process ends.

As described above, in the parking assistance apparatus according to the present embodiment, when calculating the target parking position when performing the parking assistance, the gradient change of the road surface is taken into consideration, and the target parking position is determined according to the gradient change of the road surface. It's fixed. Therefore, when performing parking assistance, the vehicle can be parked at an appropriate parking position even if there is a gradient between the position of the own vehicle and the target parking position. In the present embodiment, an example of using the automatic steering device in performing parking assistance has been described. However, the target parking position is displayed on the monitor 15 without using the automatic steering device, and a voice is appropriately output from the speaker 16. Can also be output to be used for parking assistance when the driver drives and parks. In this case, in the control routine shown in FIG. 2, step S2 is a step of calculating the target parking position, and step S5 is omitted.

Next, a second embodiment of the present invention will be described.

In this embodiment, the automatic steering device 3 of the parking assistance device 1 shown in FIG. 1 is used for control. The automatic steering device 3 according to the present embodiment is provided with a steering control section 21, an automatic steering actuator 17, and a road surface gradient detecting means 14. Others have the same configuration as that of the first embodiment.

The road gradient detecting means 14 used in the present embodiment is provided with, for example, a GPS device and a road gradient database in which road gradient information at a predetermined position is stored. The road surface gradient detecting means 14 is a CD-R that stores a GPS device and map information including road surface gradient information.
A map database such as OM and a reading device such as a CD-ROM drive for reading the map database are provided. The road surface gradient detecting means 14 can detect the current position of the own vehicle by referring to the GPS device.
Further, the road surface gradient on the map can be detected by referring to the map database by the reading device. Although the GPS device is used to detect the position of the own vehicle, other appropriate means such as a beacon device and VICS can be used.

Next, the operation of the parking assist system including the automatic steering system according to this embodiment will be described.

FIG. 5 is a flowchart of the operation of the parking assistance system according to this embodiment.

Similar to the first embodiment, when the driver puts the shift lever in the reverse range, the parking assist control for starting the parking assist is started, and the driver appropriately operates the arrow displayed on the monitor 15. The target parking position is set to a desired position on the monitor 15 without performing any operation (S11). After setting the target parking position, the parking assist ECU 2 calculates the positional relationship between the own vehicle position and the target parking position based on the two-dimensional image captured by the CCD camera 13. Subsequently, the steering control unit 21 calculates a movement locus from the own vehicle position to the target parking position from the relationship between the own vehicle position and the target parking position (S12).

After the movement locus is calculated, the position of the vehicle is detected by the GPS device in the road surface slope detecting means 14. Further, by reading the map database by the reading device, road surface gradient information from the current vehicle position to the target parking position is acquired from the map information (S13). Then, based on the acquired road surface gradient information, it is determined whether or not there is a change in the road surface gradient in the movement trajectory (S14). as a result,
If there is a change in the road surface gradient, the movement locus is corrected based on the amount of change in the road surface gradient (S15). The amount of change in road surface gradient can be recognized from the acquired road surface gradient information.

Explaining the correction of the movement locus,
As shown in FIG. 6, the point on the X-axis coordinate of the vehicle C is A, and the point on the X-axis coordinate of the target parking position is B. Here, if the function of the height of the road surface along the X axis acquired from the road surface gradient information is f (x), the road surface gradient is f ′ (x) and the road surface gradient change is f ″ (x). Now, in the section [A, B] in which the automatic steering is performed, the road surface gradient change in each minute section should be corrected in the same manner as the correction of the target parking position shown in the first embodiment. Therefore, the movement locus in the present embodiment can be corrected by the following equation (1).

[0046]

[Equation 1] In this way, the coordinate correction amount can be calculated by the equation (1). The calculated movement trajectory can be corrected based on this coordinate correction amount. Although the coordinate correction amount can be calculated directly in this way, for example,
When there is a change in the road gradient, the target parking position may be first corrected, and the movement locus may be recalculated so as to reach the corrected target parking position.

When the movement locus of the vehicle is corrected, the steering control section 21 operates the automatic steering actuator 17 according to the corrected movement locus to execute parking assistance. If it is determined in step S14 that there is no road surface gradient change in the movement trajectory, parking assistance is performed according to the movement trajectory without correcting the movement trajectory (S16).

In this way, the automatic steering of the vehicle ends and the parking assistance ends.

In the parking assistance apparatus according to the present embodiment, when calculating the movement trajectory of the vehicle when performing the parking assistance, the change in the gradient of the road surface is considered and the movement trajectory of the vehicle is corrected according to the change in the gradient of the road surface. ing. Therefore, similar to the first embodiment, when the parking assist by the automatic steering is performed, even if there is a gradient between the position of the own vehicle and the target parking position, the vehicle is parked at the appropriate parking position. Can be made.

Next, a third embodiment of the present invention will be described.

The parking assist system according to the present embodiment is applied when determining whether to continue or end parking assist in the first and second embodiments.

In the parking assistance device according to this embodiment, as shown in FIG.
The road surface gradient detecting means 14 in the parking assistance device 1 shown in (1) detects the road surface gradient from the own vehicle to the target parking position (S31), and calculates the road surface gradient change amount based on the detected road surface gradient (S32).

If the road surface gradient change amount is too large,
The correction amount of the target parking position or the movement locus becomes too large, and the parking assistance device 1 cannot accept the correction. Therefore, it is determined whether or not the road surface gradient change amount is equal to or more than a predetermined value that is a predetermined threshold value (S
33). Here, the predetermined value as the threshold value can be set as appropriate, but can be set to ± 3 degrees, for example. When the road surface gradient change amount is equal to or larger than this predetermined value, the parking assistance is ended (S34). On the other hand, when the gradient change amount of the road surface is less than the predetermined value, the parking assistance is continued (S35). In this way, by stopping the parking assistance when the allowable value of the parking assistance device is exceeded, the parking assistance can be performed safely and reliably.

In the above-described first embodiment, for example, the determination as to whether or not to stop the parking assistance is made in step S4 shown in FIG.
Can be included in the process. Further, in the second embodiment, it can be included in the process of step S15 shown in FIG.

Further, in the case where the amount of gradient change of the road surface is large, it is possible to adopt a mode in which the start of parking assistance is prohibited in order to avoid a situation in which accurate parking assistance cannot be performed. In order to prohibit the start of the parking support, in the first embodiment, the start of the parking support may be prohibited when the gradient change amount calculated in the process of step S2 is equal to or more than a predetermined threshold value. . In addition, in the second embodiment,
When the gradient change amount calculated in the process of step S12 is equal to or larger than a predetermined threshold value, the start of parking assistance may be prohibited.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, in the first embodiment, the acceleration sensor is used as the road surface gradient detecting means, but instead of this, the road surface detecting means including the GPS device, the map database, etc. used in the second embodiment, A distance sensor, a gyro sensor, etc. can be used. On the other hand, as the road surface gradient detecting means in the second embodiment, a distance measuring sensor,
A gyro sensor or the like can be used.

In addition, within a range that does not deviate from the purpose of compensating the deviation due to the change of the road surface gradient, the road surface is changed from other parameters such as the change rate of the road surface gradient or the change rate of the distance from the distance measuring sensor to the road surface in the traveling direction. It is also possible to adopt a mode in which the change in the gradient is obtained.

[0058]

As described above, according to the present invention, even if there is a change in the road surface gradient from the vehicle position to the target position, the parking assist device and the automatic steering device can appropriately move the vehicle. Can be provided.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a parking assistance device according to an embodiment of the present invention.

FIG. 2 is a flowchart of the operation of the parking assistance device according to the first embodiment of the present invention.

FIG. 3 is a schematic explanatory diagram for explaining a deviation of a target parking position that occurs when there is a change in a road surface gradient in a movement trajectory.

FIG. 4 is a graph showing a relationship between a road surface gradient change amount and a target parking position correction amount.

FIG. 5 is a flowchart of the operation of the automatic steering device according to the second embodiment of the present invention.

FIG. 6 is a schematic explanatory diagram for explaining a deviation of a movement locus that occurs when there is a change in a road surface gradient in the movement locus.

FIG. 7 is a flowchart of the operation of the parking assistance device according to the third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Parking assistance device, 2 ... Parking assistance ECU, 3 ... Automatic steering device, 11 ... Vehicle speed sensor, 12 ... Steering angle sensor, 13 ...
CCD camera, 14 ... Road gradient detecting means, 15 ... Nita,
16 ... Speaker, 17 ... Automatic steering actuator, 21
... steering control section, C ... vehicle, θ ... road surface gradient.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B60R 21/00 B60R 21/00 628F B62D 6/00 B62D 6/00 G08G 1/16 G08G 1/16 C / / B62D 101: 00 B62D 101: 00 103: 00 103: 00 113: 00 113: 00 133: 00 133: 00 137: 00 137: 00 F-term (reference) 3D032 CC20 DA03 DA24 DA25 DA76 DA82 DA87 DA88 DA90 DC08 DC33 DC34 DD02 EB04 FF01 GG01 5H180 AA01 CC04 LL01 LL02 LL07 LL09

Claims (6)

[Claims] 1. A parking assistance control device for calculating a target parking position where a vehicle is parked based on two-dimensional image information,
A parking assistance device that assists in parking the vehicle at the target parking position calculated by the parking assistance control device, comprising: a road surface gradient detecting unit that detects a road surface gradient of a road surface on which the vehicle moves; Is a parking assistance device that corrects the target parking position in accordance with a change in the road surface slope detected by the road surface slope detecting means. 2. The parking assistance according to claim 1, wherein the parking assistance control device terminates the parking assistance when a change in the road surface gradient detected by the road surface gradient detecting means becomes equal to or larger than a predetermined threshold value. Support device. 3. The parking assistance control device prohibits the start of parking assistance when the change in the road surface gradient detected by the road surface gradient detecting means is equal to or more than a predetermined threshold value. Parking assistance device. 4. An automatic steering control device that obtains a target route to a target position where the vehicle parks based on two-dimensional image information, and the vehicle is moved according to the target route calculated by the automatic steering control device. An automatic steering device comprising: an automatic steering actuator, wherein the automatic steering control device includes a road surface slope detecting means for detecting a change in a road surface slope of a road surface on which the vehicle moves, and the automatic steering control device comprises a road surface detected by the road surface slope detecting means. An automatic steering apparatus, wherein the target route is corrected according to a change in gradient. 5. The automatic steering control system according to claim 4, wherein the automatic steering control device terminates the automatic steering when the change in the road surface gradient detected by the road surface gradient detecting means becomes equal to or more than a predetermined threshold value. Steering device. 6. The automatic steering control device prohibits the start of automatic steering when the change in the road surface gradient detected by the road surface gradient detecting means is equal to or larger than a predetermined threshold value. Automatic steering device.