JP5418705B2 - Parking assistance device and parking assistance method - Google Patents

Description

The present invention relates to a parking assistance device and a parking assistance method for assisting a parking operation by guiding a vehicle to a parking target position.

Conventionally, as this type of parking assist device, the upper limit of the vehicle speed when guiding the vehicle to the parking target position is made variable according to the condition of the obstacle around the vehicle, and the upper limit of the vehicle speed is increased as the distance to the obstacle increases. Thus, it is known that the vehicle is prevented from inadvertently approaching an obstacle while ensuring the safety while shortening the travel time to the parking target position (for example, Patent Document 1). reference.).

JP 2006-335239 A

However, in the parking assistance device described in Patent Document 1, when there is no obstacle, the upper limit of the vehicle speed is set to the maximum speed, so that the actual vehicle travel locus is a guide locus particularly at a position where the steering amount is large. May be difficult to properly guide the vehicle to a desired parking target position.

The present invention was devised in view of the above-mentioned problems of the prior art, and without shortening the trajectory during movement while reducing the movement time to the parking target position of the vehicle. An object of the present invention is to provide a parking support device and a parking support method that can guide a vehicle to a parking target position.

In order to solve the above problem, the present invention sets the upper limit vehicle speed according to the steering angle deviation of the vehicle moving to the parking target position when the vehicle is guided to the parking target position while automatically controlling the steering of the vehicle. The upper limit vehicle speed is set to a lower value as the rudder angle deviation is larger, and the set upper limit vehicle speed is corrected according to the rudder angular speed of the vehicle .

According to the present invention, the upper limit vehicle speed is changed according to the steering angle deviation of the vehicle moving to the parking target position, the upper limit vehicle speed is set to a lower value as the steering angle deviation is larger, and the set upper limit vehicle speed is set to the vehicle's upper limit. Since correction is made according to the rudder angular velocity , the vehicle can be moved at a vehicle speed in a range in which no trajectory deviation occurs according to the rudder angle deviation , and the movement time to the parking target position of the vehicle is shortened. The vehicle can be guided to the parking target position without causing a shift in the locus during movement.

It is a block diagram which shows an example of the parking assistance system to which this invention is applied. It is a schematic diagram which shows the parking scene which the own vehicle moves and parks to a parking target position, retreating from a reverse start position. It is a flowchart which shows a series of operation | movement by the parking assistance system to which this invention is applied. It is a flowchart which shows the process sequence of guidance operation | movement to a parking target position in the parking assistance apparatus of 1st Embodiment. It is a graph which shows the relationship between the steering angular velocity of the own vehicle in a guidance operation | movement, and a control vehicle speed. It is a flowchart which shows the process sequence of guidance operation | movement to a parking target position in the parking assistance apparatus of 2nd Embodiment. It is a graph which shows the relationship between the steering angular speed of the own vehicle in a guidance operation | movement, and a warning vehicle speed. In the parking assistance apparatus of 3rd Embodiment, it is a flowchart which shows the process sequence of guidance operation | movement to a parking target position. It is a graph which shows the relationship between the steering angle deviation of the own vehicle in a guidance operation | movement, and a control vehicle speed. It is a flowchart which shows the process sequence of guidance operation | movement to a parking target position in the parking assistance apparatus of 4th Embodiment. It is a graph which shows the relationship between the steering angle deviation of the own vehicle during steering | guidance | derivation operation | movement, a steering angular velocity, and a warning vehicle speed. It is a graph which shows the relationship between a steering angle deviation and the correction | amendment reference value of a steering angular velocity.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[First Embodiment]
First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram of the parking support system of the present embodiment, FIG. 2 is a schematic diagram illustrating a parking scene assumed in the present embodiment, and FIG. 3 is a flowchart illustrating a series of operations by the parking support system of the present embodiment. FIG. 5 is a flowchart showing the processing procedure of the guidance operation to the parking target position, and FIG. 5 is a graph showing the relationship between the steering angular speed of the host vehicle and the control vehicle speed during the guidance operation.

As shown in FIG. 2, the parking support system according to the present embodiment assumes a parking scene in which the host vehicle V moves from the reverse start position P to the parking target position T and parks, and starts from the reverse start position P. Steering and driving / braking of the host vehicle V are automatically controlled so that the host vehicle V moves along the guide track L after obtaining the guide track L up to the parking target position T. In particular, in this embodiment, the control vehicle speed when the host vehicle V is guided from the reverse start position P to the parking target position T, that is, the upper limit value (upper limit vehicle speed) of the target vehicle speed is set as the rudder of the host vehicle V. It is made to change according to angular velocity.

As shown in FIG. 1, the parking support system according to the present embodiment is configured around a parking support controller 1 that controls the operation of the entire system. The parking assistance controller 1 includes a parking assistance start switch 2 operated by the driver of the own vehicle when starting the operation of the parking assistance system.
The right side sonar 3 and the left side sonar 4 are connected. The right side sonar 3 is a sonar that detects an obstacle on the right side of the own vehicle, and the left side sonar 4 is a sonar that detects an obstacle on the left side of the own vehicle. The signals of these sonars 3 and 4 are inputted to the parking assistance controller 1 as needed.

The parking support controller 1 also includes an electric power steering controller 5, a skid prevention device (VDC) 6, a steering angle sensor 7, a transmission (AT / CVT) via communication lines L1 and L2 of an in-vehicle network system such as CAN. 8) Engine control unit (ECM)
9, the display 10 and the audio system 11 are communicably connected. Further, a wheel speed sensor 12 is connected to the skid prevention device 6, and a back view camera 13 is connected to the display 10. The communication line L1 in FIG. 1 is a vehicle control system communication line, and the communication line L2 is an information system communication line.

The electric power steering controller 5 has a function of driving and controlling the steering of the own vehicle. The skid prevention device (VDC) 6 includes vehicle speed information from the wheel side sensor 12 and a steering angle sensor 7.
It has a function to control the brake according to the rudder angle information from. The transmission (AT / CVT) 8 has a function of controlling the speed ratio of the own vehicle. The engine control unit (ECM) 9 has a function of controlling the throttle opening of the engine. Further, the display 10 has a function of displaying an image behind the host vehicle photographed by the back view camera 13, and the audio system 11 has a function of outputting various voice guidance. An anti-lock brake system (ABS) is known as an apparatus for automatically controlling the brake of the own vehicle. Instead of the skid prevention device (VDC) 6, this anti-lock brake system (ABS) is used as a parking assist system. You may make it add to a component.

The parking support system of the present embodiment configured as described above is activated by operating the parking support start switch 2 by the driver of the own vehicle, and a processing program incorporated in advance in the parking support controller 1 is executed. As a result, the following functions (1) to (3) are mainly realized.

(1) Setting of parking target position The parking assistance controller 1 inputs the detection signal of the right side sonar 3 or the left side sonar 4 while the own vehicle is moving forward along the parking frame of the parking lot, and detects the detection signal. An empty space in which the vehicle can be parked is searched based on the signal, and when the empty space is detected, the space is automatically set as the parking target position of the vehicle. For example, in the parking scene shown in FIG. 2, in the process in which the host vehicle V is moving forward in front of the two other vehicles A and B, the two other vehicles A are detected based on the detection signal of the right side sonar 3. , B is detected as a parking target position T of the host vehicle V.

(2) Voice guidance to the reverse start position After setting the parking target position, the parking assist controller 1 inputs the vehicle speed information of the own vehicle from the skid prevention device 6 and the steering angle information of the own vehicle from the steering angle sensor 7 as needed. From the speaker of the audio system 11, voice guidance for guiding the vehicle to the optimal reverse start position for reaching the parking target position while reversing the vehicle while dead reckoning the position of the vehicle Output. For example, in the parking scene shown in FIG. 2, in the process in which the host vehicle V moves forward across the parking target position T, voice guidance such as “turn the steering to the left” is output from the speaker, and the host vehicle V When the vehicle approaches the reverse start position P, for example, voice guidance such as “stop the car and put the shift lever in reverse” is output from the speaker. The movement of the host vehicle to the reverse start position is left to the steering operation and the accelerator / brake operation by the driver of the host vehicle.

(3) Guidance from the reverse start position to the parking target position When the own vehicle reaches the reverse start position, the parking support controller 1 determines the reverse start position (automatic position relative to the target parking position based on the dead reckoning result of the own vehicle position). A relative positional relationship of the current position of the vehicle is obtained, and a guidance trajectory for guiding the host vehicle from the reverse start position to the parking target position is calculated. Then, the steering, driving, and braking of the host vehicle are automatically controlled so that the host vehicle moves from the reverse start position to the parking target position along the guidance locus. For example, in the parking scene shown in FIG. 2, when the host vehicle V reaches the reverse start position P, a guide locus that reaches the parking target position T in a neutral state after moving backward while steering rightward from the reverse start position P. L is obtained, and the steering, driving, and braking of the host vehicle V from the reverse start position P to the parking target position T are automatically controlled so that the host vehicle moves along the guidance locus L.

Here, the automatic control of the steering of the host vehicle is performed by a linked operation of the electric power steering controller 5 and the parking assist controller 1 that electrically assists the steering operation. Specifically, based on the steering angle information from the steering angle sensor 7, the parking assist controller 1 is the absolute value of the difference between the target steering angle and the actual steering angle for causing the vehicle to follow the guidance trajectory. A certain steering angle deviation is obtained, and a current command for making this steering angle deviation zero is output to the electric power steering controller 5. The electric power steering controller 5 is the parking assist controller 1
The steering actuator is driven based on the current command from the steering wheel to operate the steering.

In addition, automatic control of driving / braking of the host vehicle includes throttle opening control in the engine control device 9 based on a command from the parking support controller 1, and a gear ratio in the transmission 8 based on a command from the parking support controller 1. The control and the brake control by the skid prevention device 6 (or the anti-lock brake system) based on the command from the parking support controller 1 are performed, or a combination thereof. At this time, the parking assistance controller 1 outputs a command to each part so that the vehicle speed of the own vehicle does not exceed the control vehicle speed (upper limit vehicle speed). For example, the parking assist controller 1 outputs a throttle opening command to the engine control device 9 so that the vehicle speed of the host vehicle becomes the control vehicle speed, and when the vehicle speed of the host vehicle exceeds the control vehicle speed, the engine control device A command to reduce the throttle opening is output to 9, a brake command is output to the skid prevention device 6, or a gear ratio command is output to the transmission 8 to reduce the vehicle speed of the host vehicle.

In particular, in this embodiment, the control vehicle speed (upper limit vehicle speed) used when the parking assistance controller 1 performs automatic driving / braking control of the own vehicle is set to the rudder angular velocity of the own vehicle moving along the guidance locus ( The control vehicle speed is set low at a position where the steering angular speed increases on the guidance trajectory, and conversely, the control vehicle speed is set high at a position where the steering angular speed decreases. Yes.

In the parking support system of the present embodiment, in addition to the above main functions, when guiding the vehicle from the reverse start position to the parking target position, the rear of the vehicle photographed by the back view camera 13 is used. It also has a function of displaying an image on the display 10. That is, when the display 10 detects that the shift position of the host vehicle is reversed based on the shift position signal from the transmission 8, the display 10 captures the video signal from the back view camera 13 and displays the image behind the host vehicle. . At this time, the parking assist controller 1 generates a parking frame indicating the parking target position and an expected course based on the steering angle of the host vehicle, and displays the parking frame and the expected course in a superimposed manner on the screen of the display 10. It may be.

In the parking support system of the present embodiment, when the host vehicle is guided from the reverse start position to the parking target position, some abnormality occurs in the function of automatically controlling the driving / braking of the host vehicle or the driver of the host vehicle. However, by inadvertently performing the accelerator operation, the system is forcibly stopped when the vehicle speed of the host vehicle greatly exceeds the control vehicle speed and exceeds the release vehicle speed (for example, 4 km / h). In addition, for example, when the vehicle is guided from the reverse start position to the parking target position, when an obstacle that approaches the vehicle is detected by the right side sonar 3 or the left side sonar 4, A function of outputting a warning sound from the speaker of the system 11 may be provided.

Next, operation | movement of the parking assistance system of this embodiment is demonstrated. The parking assistance system of this embodiment starts a series of operation | movement shown to the flowchart of FIG. 3, when the parking assistance start switch 2 is operated by the driver of the own vehicle.

When the system operation is started, the parking support controller 1 first inputs detection signals of the right side sonar 3 and the left side sonar 4, and searches for an empty space where the vehicle can be parked based on these detection signals ( Step S1). And if the empty space which can park the own vehicle is detected (it is YES determination at step S2), the detected empty space is set as a parking target position of the own vehicle (step S3).

Next, the parking assistance controller 1 performs audio guidance for guiding the vehicle to the reverse start position while dead-reckoning the vehicle position based on the vehicle speed information and the steering angle information of the vehicle. (Step S4). When the vehicle reaches the reverse start position and stops (YES in step S5), a guide locus for guiding to the parking target position is calculated based on the relative positional relationship between the position and the parking target position. (Step S6).

Next, based on the shift position signal from the transmission 8, the display 10 determines whether the shift position of the host vehicle has been switched to reverse by a driver operation (step S7), and the shift position of the host vehicle is switched to reverse. If it is determined (YES in step S7), the video signal from the back view camera 13 is input and the video behind the host vehicle is displayed (step S108).
). At this time, the parking assistance controller 1 causes the parking frame indicating the parking target position and the predicted course based on the steering angle of the host vehicle to be superimposed on the screen of the display 10.

In addition, the parking assistance controller 1 steers the vehicle so that the vehicle moves to the parking target position along the guidance locus calculated in step S6 in a state where the image behind the vehicle is displayed on the display 10. And driving / braking is automatically controlled (step S9). At that time, the parking assist controller 1 controls driving and braking of the host vehicle so that the vehicle speed of the host vehicle does not exceed the control vehicle speed, and the processing procedure will be described in detail later.

While performing the above guiding operation, the parking assist controller 1 continues dead reckoning of the vehicle position based on the vehicle speed information and the steering angle information of the vehicle, and whether the vehicle has reached the parking target position. Whether or not is monitored (step S10). When the vehicle reaches the parking target position (
A determination of YES in step S10) ends the series of system operations.

The parking support controller 1 controls the vehicle speed of the host vehicle according to the processing procedure shown in the flowchart of FIG. 4 while performing the guidance operation up to the parking target position in step S9 of FIG. The processing flow of FIG. 4 is executed by the parking support controller 1 by a predetermined period (for example, 20 ms).
It is repeatedly executed for every ec).

When the processing flow of FIG. 4 is started, the parking support controller 1 firstly performs step S101.
In step S, the steering angle information is input from the steering angle sensor 7 to grasp the current steering angle of the host vehicle.
At 102, for example, the current steering angle value is calculated by first-order differentiation of the current steering angle value.

Next, the parking assistance controller 1 sets the control vehicle speed corresponding to the present steering angular speed of the own vehicle in step S103. As shown in FIG. 5, the relationship between the steering angular speed and the control vehicle speed is such that the control vehicle speed becomes lower as the steering angular speed ω increases. Specifically, the vehicle speed limit values that can follow the guidance trajectory when the steering angular velocity ω takes the maximum value and the minimum value are obtained, respectively.
As shown in a), the control vehicle speed corresponding to the steering angular speed ω may be defined by connecting these vehicle speed limit values with a straight line. Note that the change in the control vehicle speed according to the steering angular speed may be changed stepwise as shown in FIG. 5 (b) in consideration of the characteristics of the servo and the controlled object, or may change in a curve. You may make it. The parking assist controller 1 stores the relationship between the steering angular speed ω and the control vehicle speed as shown in FIG. 5 as a control map, and refers to this control map when the current steering angular speed of the host vehicle is calculated. Then, the control speed corresponding to the current steering angular speed may be set.

Next, the parking assistance controller 1 inputs vehicle speed information from the skid prevention device 6 in step S104 and grasps the current vehicle speed of the own vehicle. In step S105, the current vehicle speed of the own vehicle is set in step S103. Compare the control vehicle speed. Here, if the current vehicle speed of the host vehicle does not exceed the control vehicle speed set in accordance with the current steering angular speed, the process in the current process cycle is terminated and the process waits until the next process is started. On the other hand, when the vehicle speed of the own vehicle exceeds the control vehicle speed, the parking assist controller 1 compares the current vehicle speed of the own vehicle with a preset release vehicle speed in the next step S106, and the current vehicle speed of the own vehicle is compared. If the vehicle speed is equal to or lower than the release vehicle speed, a process of reducing the speed of the host vehicle is executed in step S107. In particular,
For example, the parking assist controller 1 outputs a command to reduce the throttle opening to the engine control device 9, outputs a brake command to the skid prevention device 6, or outputs a gear ratio command to the transmission 8. To reduce the speed of the vehicle.

On the other hand, if the vehicle speed of the host vehicle exceeds the preset release vehicle speed, the parking support controller 1 executes system release processing in step S108 and performs the parking support operation by the parking support system of the present embodiment. Stop.

As described above in detail with reference to specific examples, in the parking support system of the present embodiment, the steering, driving and braking of the own vehicle are automatically controlled to bring the own vehicle to the parking target position along the guidance trajectory. The parking assist controller 1 changes the control vehicle speed (upper limit speed) according to the steering angular speed of the host vehicle, sets the control vehicle speed low at a position where the steering angular speed increases on the guidance locus, and conversely The control vehicle speed is set high at a position where the steering angular speed is small. Therefore,
According to this parking support system, the vehicle can be guided to the parking target position along the guidance track without causing a shift in the track, and the traveling time until the vehicle reaches the parking target position can be reduced. Good parking assistance.

In the parking support system of this embodiment, when the vehicle is guided to the parking target position, all the steering, driving and braking of the vehicle are automatically controlled. The burden can be greatly reduced. In addition, this parking support system allows the driver of the vehicle to experience the optimal trajectory and changes in vehicle speed in order to park the vehicle properly at the parking target position. It is also effective in learning appropriate steering, accelerator and brake operations.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The parking assistance system of this embodiment is
The guiding operation from the reverse start position to the parking target position is different from that of the first embodiment.

That is, in the parking support system of the first embodiment, until the own vehicle reaches the parking target position from the reverse start position, all of the steering, driving and braking of the own vehicle are automatically controlled.
In the parking assistance system of this embodiment, only steering control is performed by automatic control, and driving / braking is left to the accelerator / brake operation of the driver of the vehicle. When the vehicle speed exceeds the warning vehicle speed until the host vehicle reaches the parking target position from the reverse start position, the display 10
The warning is given to the driver of the host vehicle by the display by the sound and the sound output from the speaker of the audio system 11, and the warning vehicle speed at this time, that is, the upper limit value of the vehicle speed allowed without warning (upper limit vehicle speed). ) Is changed according to the rudder angular speed of the vehicle.

The configuration of the parking assistance system of this embodiment is the same as that of the first embodiment shown in FIG. However, in the parking support system of the present embodiment, the output of the throttle opening command from the parking support controller 1 to the engine control device 9, the output of the brake command to the skid prevention device 6, and the gear ratio command to the transmission 8. Instead, the warning operation using the display 10 and the audio system 11 is performed when the vehicle speed of the host vehicle exceeds the warning vehicle speed.

The series of operations in the parking support system of the present embodiment is the same as that in the parking support system of the first embodiment shown in the flowchart of FIG. 3 except for the operation when guiding the host vehicle from the reverse start position to the parking target position. The operation is the same. In the parking assistance system of the present embodiment, when the vehicle is guided from the reverse start position to the parking target position (step S9 in FIG. 3), the parking assistance controller 1 moves the vehicle to the parking target position along the guidance locus. The steering of the vehicle is automatically controlled so as to move. At this time, the driving / braking of the host vehicle is performed by the accelerator / brake operation of the driver, but the parking support controller 1 monitors the vehicle speed of the host vehicle in accordance with the processing procedure shown in the flowchart of FIG. 6, and the vehicle speed exceeds the warning vehicle speed. And output a warning. Note that the processing flow of FIG. 6 is repeatedly executed by the parking support controller 1 at predetermined intervals (for example, about 20 msec) while the host vehicle is guided from the reverse start position to the parking target position. .

When the flow of FIG. 6 is started, the parking assist controller 1 first inputs the steering angle information from the steering angle sensor 7 in step S201, grasps the current steering angle of the host vehicle, and step S20.
In step 2, for example, the current steering angle speed is calculated by first-order differentiation of the current steering angle value.

Next, in step S203, the parking assist controller 1 sets a warning vehicle speed corresponding to the current steering angular speed of the host vehicle. As shown in FIG. 7, the relationship between the steering angular speed and the warning vehicle speed is such that the warning vehicle speed becomes lower as the steering angular speed ω increases. Note that the change in the warning vehicle speed according to the steering angular speed ω may be changed linearly, stepwise, or curved, similar to the change in the control vehicle speed described in the first embodiment. It is good also as what changes. The parking assist controller 1 stores the relationship between the steering angular speed ω and the warning vehicle speed as shown in FIG. 7 as a control map, and refers to this control map when the current steering angular speed of the host vehicle is calculated. Then, a warning speed corresponding to the current rudder angular speed may be set.

Next, in step S204, the parking support controller 1 inputs vehicle speed information from the skid prevention device 6 to grasp the current vehicle speed of the own vehicle. In step S205, the current vehicle speed of the own vehicle is set in step S203. Compare the warning vehicle speed. Here, if the current vehicle speed of the host vehicle does not exceed the warning vehicle speed set according to the current steering angular speed, it is checked in step S206 whether or not the speed warning is output in the previous processing cycle, and the speed warning is performed. If it is being output, the speed warning is canceled in step S207. If the speed warning is not being output, the process in the current processing cycle is terminated, and the process waits until the next process is started.

If the parking support controller 1 determines in step S205 that the vehicle speed of the host vehicle exceeds the warning vehicle speed, the parking support controller 1 compares the current vehicle speed of the host vehicle with a preset release vehicle speed in step S208. If the current vehicle speed of the host vehicle is equal to or less than the release vehicle speed, a speed warning indicating that the vehicle speed is excessive is issued in step S209 to prompt the driver to operate the brake. Specifically, the parking support controller 1 displays a message indicating that the vehicle speed is excessive, for example, on the display 10, and outputs a warning sound or a voice message from the speaker of the audio system 11.

On the other hand, if the vehicle speed of the host vehicle exceeds the preset release vehicle speed, the parking support controller 1 executes system release processing in step S210 and performs the parking support operation by the parking support system of the present embodiment. Stop.

As described above in detail with specific examples, in the parking support system of the present embodiment, a warning is issued when the vehicle speed exceeds the warning vehicle speed by the driver's accelerator / brake operation while automatically controlling the steering of the host vehicle. When the vehicle is moved to the parking target position along the guidance trajectory in such a manner, the parking assistance controller 1 gives a warning vehicle speed (upper limit speed) according to the steering angular speed of the vehicle.
Is changed so that the warning vehicle speed is set low at a position where the rudder angular speed is large on the guidance locus, and conversely, the warning vehicle speed is set high at a position where the rudder angular speed is small. Therefore, according to this parking assistance system, as in the first embodiment, the vehicle can be guided to the parking target position along the guidance track without causing a shift in the track, and the parking target position can be set. Travel time to reach can be shortened and efficient parking assistance can be performed.

In the parking support system of this embodiment, when the vehicle is guided to the parking target position, only the steering of the vehicle is automatically controlled, and the accelerator / brake operation is performed by the driver. Appropriate parking assistance can be performed while reducing the above.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The parking assistance system of this embodiment is
As in the first embodiment, when the vehicle is guided from the reverse start position to the parking target position, all the steering, driving and braking of the own vehicle are automatically controlled. A certain control vehicle speed (upper limit vehicle speed) is changed in accordance with a rudder angle deviation which is an absolute value of a difference between a target rudder angle and an actual rudder angle for causing the host vehicle to follow the guidance trajectory.

The configuration of the parking assistance system of this embodiment is the same as that of the first embodiment shown in FIG. A series of operations in the parking support system of this embodiment is the same as the operations in the parking support system of the first embodiment shown in the flowchart of FIG. However, in the parking support system of the present embodiment, when the vehicle is guided from the reverse start position to the parking target position (step S9 in FIG. 3), the parking support controller 1 performs a series of steps shown in the flowchart of FIG. The vehicle speed of the host vehicle is controlled according to the processing procedure. Note that the processing flow of FIG. 8 is repeatedly executed by the parking support controller 1 at predetermined intervals (for example, about 20 msec) while guiding the host vehicle from the reverse start position to the parking target position. .

When the processing flow of FIG. 8 is started, the parking support controller 1 firstly performs step S301.
The steering angle information is input from the steering angle sensor 7 to grasp the current steering angle of the vehicle. And
In step S302, a difference between the target rudder angle for guiding the host vehicle along the guidance trajectory and the current rudder angle is obtained, and a rudder angle deviation is calculated.

Next, the parking assistance controller 1 sets the control vehicle speed corresponding to the steering angle deviation calculated in step S302 in step S303. As shown in FIG. 9, the relationship between the steering angle deviation and the control vehicle speed is such that the control vehicle speed becomes lower as the steering angle deviation θd is larger. Specifically, vehicle speed limit values that can follow the guidance trajectory when the steering angle deviation θd takes the maximum value and the minimum value are respectively obtained, and the control vehicle speed corresponding to the steering angle speed θd is determined based on these vehicle speed limit values. Can be defined. Note that the change in the control vehicle speed according to the steering angle deviation θd may change linearly or in a step-like manner, similar to the change in the control vehicle speed according to the steering angle speed described in the first embodiment. It may be changed or changed in a curve. Parking support controller 1
9 stores the relationship between the steering angle deviation θd and the control vehicle speed as shown in FIG. 9 as a control map, and this control is performed when the steering angle deviation between the target steering angle and the actual steering angle is calculated. The control speed corresponding to the current steering angle deviation may be set with reference to the map.

Next, the parking assistance controller 1 inputs vehicle speed information from the skid prevention device 6 in step S304 and grasps the current vehicle speed of the host vehicle. In step S305, the current vehicle speed of the host vehicle is set in step S303. Compare the control vehicle speed. Here, if the current vehicle speed of the host vehicle does not exceed the control vehicle speed set according to the steering angle deviation, the processing in the current processing cycle is terminated, and the process waits until the next processing is started. On the other hand, when the vehicle speed of the own vehicle exceeds the control vehicle speed, the parking assist controller 1 compares the current vehicle speed of the own vehicle with a preset release vehicle speed in the next step S306, and determines the current vehicle speed. If the vehicle speed is equal to or lower than the release vehicle speed, a speed reduction process as described in the first embodiment is executed in step S307.

On the other hand, if the vehicle speed of the host vehicle exceeds the preset release vehicle speed, the parking support controller 1 executes system release processing in step S308 and performs the parking support operation by the parking support system of the present embodiment. Stop.

As described above in detail with reference to specific examples, in the parking support system of the present embodiment, the steering, driving and braking of the own vehicle are automatically controlled to bring the own vehicle to the parking target position along the guidance trajectory. In the position where the parking assist controller 1 changes the control vehicle speed (upper limit speed) according to the steering angle deviation between the target steering angle and the actual steering angle, and the steering angle deviation becomes large on the guidance trajectory. The control vehicle speed is set low, and conversely, the control vehicle speed is set high at a position where the steering angle deviation is small. Therefore, according to this parking assistance system, as in the first embodiment, the vehicle can be guided to the parking target position along the guidance track without causing a shift in the track,
The traveling time until the parking target position is reached can be shortened, and efficient parking assistance can be performed.

Further, in the parking support system of the present embodiment, the control vehicle speed is set using the information on the steering angle deviation used when automatically controlling the steering of the host vehicle as a parameter, and therefore the steering angular speed is used to set the control vehicle speed. It is not necessary to calculate new parameters such as the above, and the processing load can be reduced.

The above is based on the premise of a system that automatically controls all of the steering and driving / braking of the host vehicle at the time of guidance to the parking target position, and an example in which the steering angle deviation is used instead of the steering angular speed as a parameter for setting the control vehicle speed. As described in the second embodiment, the steering angular speed is used as a parameter for setting the warning vehicle speed in a system in which only steering control is performed by automatic control and driving / braking is left to the accelerator / brake operation of the driver of the own vehicle. It is also possible to use a rudder angle deviation instead of.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. The parking assistance system of this embodiment is
As in the first embodiment, when the vehicle is guided from the reverse start position to the parking target position, all the steering, driving and braking of the own vehicle are automatically controlled. A certain control vehicle speed (upper limit vehicle speed) is set based on the steering angle deviation, and the control vehicle speed is corrected in accordance with the steering angle speed.

The configuration of the parking assistance system of this embodiment is the same as that of the first embodiment shown in FIG. A series of operations in the parking support system of this embodiment is the same as the operations in the parking support system of the first embodiment shown in the flowchart of FIG. However, in the parking support system of the present embodiment, when the vehicle is guided from the reverse start position to the parking target position (step S9 in FIG. 3), the parking support controller 1 performs a series of steps shown in the flowchart of FIG. The vehicle speed of the host vehicle is controlled according to the processing procedure. Note that FIG.
This processing flow is repeatedly executed by the parking support controller 1 at predetermined intervals (for example, about 20 msec) while the host vehicle is guided from the reverse start position to the parking target position.

When the processing flow of FIG. 10 is started, the parking support controller 1 first performs step S40.
1, the steering angle information is input from the steering angle sensor 7 to grasp the current steering angle of the vehicle. In step S402, the difference between the target rudder angle for guiding the host vehicle along the guidance trajectory and the current rudder angle is obtained to calculate the rudder angle deviation, and the current rudder angle value is first-order differentiated. Thus, the current steering angular speed is calculated.

Next, the parking assistance controller 1 sets the control vehicle speed corresponding to the steering angle deviation calculated in step S402 in the same manner as in the first embodiment in step S403. Furthermore, the parking assistance controller 1 performs step S404 through the processing in steps S404 to S408.
In consideration of the relationship between the current steering angle deviation calculated in 402 and the steering angular speed, as shown in FIG.
By correcting the control vehicle speed corresponding to the steering angle deviation θd based on the steering angular speed ω, the control vehicle speed is increased when the steering angular speed ω is large, and the control vehicle speed is decreased when the steering angular speed ω is small. Improve tolerance to system delays and disturbances.

Specifically, in step S404, the parking assistance controller 1 calculates a correction reference value for the steering angular speed corresponding to the current steering angle deviation based on the standard steering angular speed of the system corresponding to the steering angle deviation. The relationship between the rudder angle deviation and the rudder angular speed correction reference value is, for example, as shown in FIG.
In accordance with the value of the steering angle deviation θd, the value shifted upward at a predetermined ratio with respect to the standard steering angular velocity value ω of the system (broken line in the figure) is shifted downward to the negative correction reference value. The value is calculated as a positive correction reference value. In step S405, it is determined whether the current rudder angular velocity calculated in step S402 exceeds the -side correction reference value. If the current rudder angular velocity exceeds the -side correction reference value, in step S406. The control vehicle speed corresponding to the rudder angle deviation set in step S403 is corrected to the negative side (for example, -10%).

On the other hand, if the current steering angular speed does not exceed the negative correction reference value, it is determined in step S407 whether the current steering angular speed is less than the positive correction reference value.
If it is less than the side correction reference value, in step S408, the control vehicle speed corresponding to the steering angle deviation set in step S403 is corrected to the + side (for example, + 10%). When the current steering angular speed is between the negative correction reference value and the positive correction reference value, the control vehicle speed corresponding to the steering angle deviation set in step S403 is maintained without being corrected.

Next, in step S409, the parking assist controller 1 inputs vehicle speed information from the skid prevention device 6 to grasp the current vehicle speed of the host vehicle, and in step S410, the current vehicle speed of the host vehicle and the corrected control vehicle speed. And compare. Here, if the current vehicle speed of the own vehicle does not exceed the corrected control vehicle speed, the processing in the current processing cycle is terminated, and the process waits until the next processing is started. On the other hand, if the vehicle speed of the host vehicle exceeds the corrected control vehicle speed, the parking assist controller 1 compares the current vehicle speed of the host vehicle with a preset release vehicle speed in the next step S411, and If the current vehicle speed of the vehicle is equal to or lower than the release vehicle speed, a speed reduction process as described in the first embodiment is executed in step S412.

On the other hand, if the vehicle speed of the host vehicle exceeds the preset release vehicle speed, the parking support controller 1 executes system release processing in step S413 and performs the parking support operation by the parking support system of the present embodiment. Stop.

As described above in detail with reference to specific examples, in the parking support system of the present embodiment, the steering, driving and braking of the own vehicle are automatically controlled to bring the own vehicle to the parking target position along the guidance trajectory. The parking assist controller 1 changes the control vehicle speed (upper speed) according to the steering angle deviation between the target rudder angle and the actual rudder angle, and further sets the control based on the rudder angle deviation. The vehicle speed is corrected according to the rudder angular speed. Therefore, according to this parking assistance system, as in the first embodiment, the vehicle can be guided to the parking target position along the guidance track without causing a shift in the track, and the parking target position can be set. It is possible to shorten the travel time to reach the vehicle, to provide efficient parking support, and to improve the resistance to delay and disturbance of the control system, thereby ensuring the stability of the system.

The above is based on the premise of a system that automatically controls all of the steering and driving / braking of the host vehicle at the time of guidance to the parking target position, and an example in which the steering angle deviation is used instead of the steering angular speed as a parameter for setting the control vehicle speed. As described in the second embodiment, the steering angular speed is used as a parameter for setting the warning vehicle speed in a system in which only steering control is performed by automatic control and driving / braking is left to the accelerator / brake operation of the driver of the own vehicle. It is also possible to use a rudder angle deviation instead of.

In the above example, the control vehicle speed set based on the current steering angle deviation of the own vehicle is corrected according to the current rudder angular speed, but is set based on the current steering angular speed of the own vehicle. Even if the control vehicle speed or the warning vehicle speed is corrected according to the steering angle deviation, the effect of improving the resistance to delay and disturbance of the control system can be obtained and the stability of the system can be ensured as in the above example. It becomes possible to do.

Hereinafter, as a reference, a correspondence relationship between each of the above-described embodiments and the constituent elements described in the claims is added. In the parking assistance system of each embodiment described above, the steering angle sensor 7 connected to the parking assistance controller 1 corresponds to “steering angle detection means” described in the claims.

Further, the process by the parking assist controller 1 that sets the control vehicle speed or the warning vehicle speed according to the current steering angular speed or steering angle deviation of the host vehicle (for example, step S103 in the flowchart of FIG. 4).
Is equivalent to “upper limit vehicle speed setting means” described in the claims. Further, the wheel speed sensor 12 connected to the skid prevention device 6 corresponds to “vehicle speed detection means” described in the claims. Further, processing by the parking support controller 1 that outputs a control command to the engine control device 9, the skid prevention device 6, and the transmission 8 (for example, step S in the flowchart of FIG. 4).
107) corresponds to “drive control means” described in the claims. Further, the processing by the parking support controller 1 for displaying a message or the like on the display 10 or outputting a warning sound or a voice message from the speaker of the audio system 11 (for example, the processing in step S209 in the flowchart of FIG. 6) is claimed. `` Alarm means '' described in the range
It corresponds to.

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

DESCRIPTION OF SYMBOLS 1 Parking assistance controller 5 Electric power steering controller 6 Side slip prevention device 7 Steering angle sensor 8 Transmission 9 Engine control device 10 Display 11 Audio system 12 Wheel speed sensor

Claims (4)

In the parking assistance device that automatically controls the steering of the vehicle to guide the vehicle to the parking target position,
Rudder angle detecting means for detecting the rudder angle of the vehicle;
The upper limit vehicle speed is changed according to the steering angle deviation of the vehicle that is moving to the parking target position, the upper limit vehicle speed is set to a lower value as the steering angle deviation is larger , and the set upper limit vehicle speed is set according to the steering angular speed of the vehicle. And an upper limit vehicle speed setting means for correcting the parking speed. Vehicle speed detection means for detecting the vehicle speed;
The parking assist device according to claim 1 , further comprising drive control means for automatically controlling driving and braking of the vehicle so that the vehicle speed moving to the parking target position does not exceed the upper limit vehicle speed. Vehicle speed detection means for detecting the vehicle speed;
The parking assist device according to claim 1 , further comprising alarm means for outputting a warning when the vehicle speed moving to the parking target position exceeds the upper limit vehicle speed. When guiding the vehicle to the parking target position while automatically controlling the steering of the vehicle, the upper limit vehicle speed is changed according to the steering angle deviation of the vehicle moving to the parking target position, and the higher the steering angle deviation, the higher the upper limit vehicle speed. Is set to a low value, and the set upper limit vehicle speed is corrected in accordance with the steering angular speed of the vehicle .

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