Travel assistance device

Abstract

A travel assistance device according to the present invention detects an obstacle on the basis of the detection results of ultrasonic sensors (9E-9H) provided in a vehicle during parking assistance or parking-out assistance of the vehicle. Furthermore, a plurality of ultrasonic sensors (9E-9H) are provided on the side surface of the vehicle (2) in a positional relationship such that the ultrasonic sensors (9E-9H) cannot receive the indirect waves from each other, and when the ultrasonic sensors (9E-9H) detect a lateral obstacle at the time of starting the parking assistance or parking-out assistance of the vehicle, the ultrasonic sensors (9E-9H) start the parking assistance or parking-out assistance of the vehicle. The approach to the detected side obstacle is restricted during a period from the start of parking assistance or parking-out assistance of the vehicle until a predetermined condition is satisfied.

Description

Technical Field

[0001] This invention relates to a driving assistance device for assisting the driving of a vehicle. Background Technology

[0002] Previously, a driving assistance device was proposed that assists driving by displaying camera images of the vehicle's surroundings while the vehicle is in motion, issuing warnings to people or obstacles in the vicinity, or performing some or all of the user's driving operations on the side of the vehicle.

[0003] Here, as one of the aforementioned driving assistance methods, a parking assistance method that performs part or all of the driving operations when parking the vehicle, or an exit assistance method that performs part or all of the driving operations when leaving a parking position, is known. For example, Japanese Patent Application Publication No. 2005-96703 discloses a driving assistance device in which, when leaving or parking the vehicle, a user located outside the vehicle instructs the user to move forward or backward via a terminal, and the vehicle moves according to the user's instructions, avoiding obstacles detected by an obstacle detection unit.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2005-96703 (paragraphs 0035-0059)

[0005] Here, as described in the aforementioned Patent Document 1, when a user performs parking assistance or exit assistance via a terminal operation from outside the vehicle, the parking or exit instruction is received essentially while the vehicle's ignition switch is off. Therefore, parking assistance or exit assistance begins after the ignition switch is turned on, before the vehicle moves.

[0006] On the other hand, units that detect obstacles around a vehicle often use ranging sensors such as ultrasonic sensors, millimeter-wave sensors, and LiDAR sensors. These sensors detect obstacles while the vehicle is moving, allowing for accurate determination of obstacle positions via triangulation. However, triangulation is not valid when the ignition switch is turned on but the vehicle is not moving, thus reducing the accuracy of obstacle detection. Therefore, this effect needs to be considered when initiating parking assist or exit assist after the ignition switch is turned on but before the vehicle is moving. Summary of the Invention

[0007] The present invention was made to solve the above-mentioned problems, and its purpose is to provide a driving assistance device that can perform parking assistance or parking assistance that takes into account the above-mentioned effects when an obstacle is detected at the moment when the vehicle starts parking assistance or parking assistance.

[0008] To achieve the above objectives, the driving assistance device of the present invention, in the parking assistance or exiting-the-garage assistance of a vehicle, detects obstacles based on the detection results of the distance measuring sensors provided by the vehicle. The distance measuring sensors are arranged in a positional relationship where they cannot receive indirect waves from each other on the side of the vehicle. When the parking assistance or exiting-the-garage assistance of the vehicle begins, if the distance measuring sensors detect a lateral obstacle as the obstacle on the side of the vehicle, the device restricts approach to the lateral obstacle from the start of the parking assistance or exiting-the-garage assistance until a predetermined condition is met.

[0009] According to the driving assistance device of the present invention having the above structure, since it restricts the approach to obstacles detected on the side of the vehicle from the start of parking assistance or exit assistance until the specified conditions are met, it can prevent the action of approaching the obstacle even when the detection accuracy of the obstacle decreases at the beginning of parking assistance or exit assistance. Attached Figure Description

[0010] Figure 1 This is a schematic structural diagram of the vehicle according to this embodiment.

[0011] Figure 2 This diagram shows an example of an ultrasonic sensor positioned at the front of a vehicle.

[0012] Figure 3 This diagram shows an example of an ultrasonic sensor being configured on the side of a vehicle.

[0013] Figure 4 This is a block diagram showing the structure of the driving assistance device in this embodiment.

[0014] Figure 5 This is a flowchart of the driving assistance processing procedure in this embodiment.

[0015] Figure 6 This is a diagram showing the detection range of obstacles that can be detected by ultrasonic sensors installed on the vehicle.

[0016] Figure 7 This diagram illustrates an example of generating a driving trajectory without restricting approach to lateral obstacles detected at the start of the exit assist.

[0017] Figure 8 This diagram illustrates the problem points when generating a driving trajectory without restricting approach to lateral obstacles detected at the start of the exit assist.

[0018] Figure 9 This diagram illustrates the problem points when generating a driving trajectory without restricting approach to lateral obstacles detected at the start of the exit assist.

[0019] Figure 10 This diagram illustrates an example of how a driving trajectory is generated when the vehicle is limited to approaching a lateral obstacle detected at the start of the exit assist.

[0020] Figure 11 This diagram illustrates the detection of obstacles using triangulation in an ultrasonic sensor.

[0021] Figure 12 This diagram illustrates an example of how a driving trajectory is generated when the vehicle is limited to approaching a lateral obstacle detected at the start of the exit assist.

[0022] Figure 13 This diagram illustrates the problem when generating a driving trajectory by limiting only lateral obstacles detected by specific ultrasonic sensors.

[0023] Figure 14 This diagram illustrates the problem points when generating a driving trajectory by extending the limitation object to lateral obstacles detected by all ultrasonic sensors.

[0024] Figure 15 This diagram illustrates the problem points when generating a driving trajectory without restricting approach to lateral obstacles detected at the start of parking assist.

[0025] Figure 16 This diagram illustrates an example of how a driving trajectory is generated when the vehicle is limited to approaching a lateral obstacle detected at the start of parking assistance.

[0026] Explanation of reference numerals in the attached figures

[0027] 1: Driving assistance device; 2: Vehicle; 3: Control unit; 9A-9L: Ultrasonic sensor (distance sensor); 10: Driving assistance ECU; 31: CPU; 39: Remote control; 55: Garage (side obstacles); 56: Obstacle; 57: Driving trajectory Detailed Implementation

[0028] Hereinafter, a specific embodiment of the driving assistance device of the present invention will be described in detail with reference to the accompanying drawings. First, a vehicle 2 equipped with the driving assistance device 1 of this embodiment will be described. Figure 1 This is a schematic structural diagram of vehicle 2 according to this embodiment.

[0029] Here, vehicle 2 can be, for example, a car powered by an internal combustion engine (engine, etc.) (internal combustion engine car), a car powered by an electric motor (motor, etc.) (electric car, fuel cell car, etc.), or a car powered by both (hybrid car). Furthermore, the vehicle type is not limited; it can be a regular car, or a large commercial truck, bus, construction machinery, etc. Also, although described below as a four-wheeled vehicle, it can also be a two-wheeled or three-wheeled vehicle.

[0030] However, vehicle 2 is an assisted driving vehicle that can drive automatically without relying on user driving operations, in addition to manual driving based on user driving operations.

[0031] Furthermore, autonomous driving assistance can be implemented only in specific situations such as parking or exiting a parking space, or it can be implemented across all road sections, or only while the vehicle is traveling on a specific road section (e.g., a highway with entrances and exits at the boundary (regardless of whether there are people or not, or whether it is toll-free)). In the following description, it will be explained that the autonomous driving area for which autonomous driving assistance is implemented includes not only all road sections, including general roads and highways, but also parking lots, and it is implemented only when the user selects to implement autonomous driving assistance (e.g., presses the autonomous driving start button) and it is determined that autonomous driving assistance-based driving is possible. On the other hand, vehicle 2 can also be a vehicle that can only perform assisted driving based on autonomous driving assistance. Alternatively, it can be implemented only for driving from parking to a parking space (i.e., parking assistance) or driving to exit from a parking space (i.e., exit assistance).

[0032] Furthermore, in the vehicle control within the automated driving assistance system of this embodiment, for example, the vehicle's current position, the driving lane, and the positions of surrounding obstacles are constantly detected, and vehicle control of the steering device, drive source, brakes, etc., is automatically performed to drive along the generated driving trajectory at a speed according to the same generated speed plan. In particular, parking assistance and exiting a parking space can also be performed by operating a remote control while the user is out of the vehicle. The remote control is, for example, an operating terminal capable of instructing "forward" or "backward." For instance, when the user instructs "forward," as described later, the surrounding conditions are confirmed using the detection results of sensors or cameras, and the trajectory for moving forward from the vehicle's current position is calculated. Vehicle control is automatically performed to move the vehicle along the calculated trajectory to enter or exit the parking space. On the other hand, when the user instructs "backward," as described later, the surrounding conditions are confirmed using the detection results of sensors or cameras, and the trajectory for moving backward from the vehicle's current position is calculated. Vehicle control is automatically performed to move the vehicle backward along the calculated trajectory to enter or exit the parking space. However, parking assistance and exit assistance are not limited to the above methods. For example, they can also be performed while the passenger is in the vehicle. By specifying the parking location and exit location, a trajectory to that location can be generated, and the vehicle can drive automatically along that trajectory.

[0033] In addition, such as Figure 1 As shown, vehicle 2 includes: an operation unit 3 for receiving operations from passengers; an LCD display 4 for displaying bird's-eye view, overhead view, and other information related to driving assistance to passengers; a speaker 5 for outputting voice guidance related to driving assistance; a front camera 6, a rear camera 7, and side cameras 8A and 8B for capturing images of the vehicle's surroundings; ultrasonic sensors 9A to 9L for detecting obstacles around the vehicle; and a driving assistance ECU (electronic control unit) 10 for performing various calculations based on input information. Furthermore, various structural components, including the aforementioned driving assistance ECU 10, are designated as driving assistance devices 1.

[0034] The structural components of vehicle 2 will now be described. First, the operation unit 3 is located, for example, in front of the steering wheel (also called the steering mechanism), and includes operation buttons that are activated when autonomous driving assistance is initiated. By operating the operation unit 3, the user can switch between manual driving, which is based on the user's driving operations, and assisted driving, which is based on autonomous driving assistance, where the vehicle drives automatically without the user's driving operations. Furthermore, the operation unit 3 may also have a touch panel located in front of the LCD display 4. Additionally, it may include a microphone and a voice recognition device. Furthermore, in this embodiment, one of the operation units 3 that is operated by the passenger also includes a remote control (operation terminal) that can be operated from outside the vehicle (described later).

[0035] The LCD display 4 is mounted on the instrument panel of vehicle 2. During autonomous driving assistance, it displays bird's-eye view and overhead view images of the vehicle's surroundings, generated by viewpoint conversion and compositing of images captured by the front camera 6, rear camera 7, and side cameras 8A and 8B. Furthermore, if there are pedestrians or other objects of warning around vehicle 2, a warning image indicating the presence of the object can be displayed at the location of the object in the bird's-eye view or overhead view. Additionally, the LCD display 4 can also be used as a display for a navigation device.

[0036] Additionally, speaker 5 is mounted on the instrument panel of vehicle 2, outputting guidance voices and warning sounds related to driver assistance. Furthermore, speaker 5 can also be used as a speaker for the navigation system.

[0037] In addition, the front camera 6 is, for example, a camera device that uses a solid-state imaging element such as a CCD, and is installed, for example, above the front bumper of the vehicle 2, behind the rearview mirror, etc., with the optical axis facing forward in the direction of the vehicle's travel.

[0038] The rear camera 7 is also a camera device that uses a solid-state imaging element such as a CCD. For example, it is installed near the center above the license plate at the rear of the vehicle 2, with the optical axis pointing towards the rear of the vehicle.

[0039] Furthermore, the side cameras 8A and 8B are also shooting devices that use solid-state imaging elements such as CCDs, for example, mounted on the left and right side mirrors of vehicle 2, with the optical axis direction facing the side of the vehicle.

[0040] Furthermore, the driver assistance ECU 10 performs viewpoint conversion and synthesis processing on the images captured by the aforementioned front camera 6, rear camera 7, and side cameras 8A and 8B to generate bird's-eye view and overhead view images of the vehicle's surroundings. Additionally, during automated driving assistance execution, image recognition processing is performed on the captured images to detect lane markings, parking lines, and obstacles (other vehicles, pedestrians, bicycles, walls, guardrails, and other structures) around the vehicle, and automated driving assistance is executed based on the detection results. In particular, during parking assistance and exiting parking spaces, the obstacle detection results based on the aforementioned cameras are used to confirm the parking space and its surrounding conditions.

[0041] On the other hand, ultrasonic sensors 9A to 9L are respectively arranged at predetermined intervals at the front, rear, and sides of the vehicle. They emit ultrasonic waves as detection waves around the vehicle 2 and receive reflected waves after the emitted detection waves are reflected by objects located around the vehicle, thereby detecting objects that reflected the detection waves. Specifically, this ultrasonic sensor is a type of ranging sensor. By measuring the time from emitting the detection wave to receiving the reflected wave, it can detect the distance (range) between itself and the object that reflected the detection wave. In addition, ultrasonic sensors 9A to 9L are configured to generate an output signal (including the distance to the detected object) corresponding to the reception result of the received wave and output it to the control unit. Furthermore, objects that can be detected by ultrasonic sensors 9A to 9L include, for example, pedestrians, bicycles, other vehicles, walls, and other obstacles that the vehicle 2 needs to avoid while driving, or obstacles that define parking spaces. In addition, millimeter-wave sensors or LiDAR sensors can be used instead of ultrasonic sensors as ranging sensors.

[0042] Furthermore, the placement and orientation of each ultrasonic sensor 9A-9L can be appropriately set. However, in this embodiment, to cover the entire area in front of, behind, and to the left and right sides of the vehicle 2's direction of travel as the detection range for the object, ultrasonic sensors 9A-9D are positioned in front of the vehicle 2 with the direction of wave transmission facing forward in the direction of travel. Ultrasonic sensors 9E and 9F are positioned to the left of the vehicle 2 with the direction of wave transmission facing left in the direction of travel. Ultrasonic sensors 9G and 9H are positioned to the right of the vehicle 2 with the direction of wave transmission facing right in the direction of travel. Ultrasonic sensors 9I-9L are positioned behind the vehicle 2 with the direction of wave transmission facing rear in the direction opposite to the direction of travel. All ultrasonic sensors 9A-9L are positioned at the same height above the ground surface.

[0043] In particular, the explanation will take ultrasonic sensors 9A to 9D as examples, such as... Figure 2 As shown, ultrasonic sensors 9A to 9D are preferably positioned at different locations around the front bumper or the front grille above the vehicle 2, and are evenly spaced apart in the left-right direction without deviation, so as to send detection waves over a wider area in front of the vehicle (i.e., to make the detectable range of objects wider).

[0044] Specifically, such as Figure 2As shown, ultrasonic sensor 9A is positioned near the left front corner of vehicle 2, with the direction of transmission of the detection wave slightly tilted to the left of the vehicle 2's direction of travel, to transmit the detection wave to the left front of vehicle 2. Ultrasonic sensor 9B is positioned slightly to the left of the vehicle 2's centerline, with the direction of transmission of the detection wave facing the vehicle's direction of travel, to transmit the detection wave centered on the front, especially the left side, of vehicle 2. Ultrasonic sensor 9C is positioned slightly to the right of the vehicle 2's centerline, with the direction of transmission of the detection wave facing the vehicle's direction of travel, to transmit the detection wave centered on the front, especially the right side, of vehicle 2. Ultrasonic sensor 9D is positioned near the right front corner of vehicle 2, with the direction of transmission of the detection wave slightly tilted to the right of the vehicle 2's direction of travel, to transmit the detection wave to the right front of vehicle 2. Ultrasonic sensors 9A and 9D, and ultrasonic sensors 9B and 9C, are arranged across the vehicle's centerline in a top-down view. Furthermore, although not shown in the diagram, ultrasonic sensors 9I to 9L at the rear of vehicle 2 are also arranged symmetrically in the same manner.

[0045] On the other hand, such as Figure 3 As shown, the ultrasonic sensors 9E and 9F on the sides are configured to send detection waves in a direction 90 degrees intersecting the direction of travel of vehicle 2. Compared to the front or rear of the vehicle described above, the number of sensors installed on the sides is relatively small. Therefore, there are areas where objects cannot be directly detected by ultrasonic sensors 9E and 9F. However, the presence and location of objects can be inferred from the detection history of objects by ultrasonic sensors 9A to 9L in these areas. Furthermore, although not shown in the figure, the ultrasonic sensors 9G and 9H on the right side of vehicle 2 are also arranged symmetrically on both sides in the same manner.

[0046] Furthermore, in this embodiment, the ultrasonic sensors 9A to 9L, especially the ultrasonic sensors 9A to 9D at the front of vehicle 2 and the ultrasonic sensors 9I to 9L at the rear of vehicle 2, are positioned so that they can receive reflected waves as indirect waves between adjacent sensors. Therefore, by receiving both direct and indirect waves, not only can the distance to the object be determined, but also the specific position of the object (relative to the vehicle) can be determined using triangulation. As for the side ultrasonic sensors 9E to 9H, since they are separately positioned, they cannot receive indirect waves. However, by using triangulation to measure the distance measured at the previous position, the distance measured at the current position, and the distance traveled between them, the specific position of the object (relative to the vehicle) can also be determined by the movement of the vehicle.

[0047] On the other hand, the driver assistance ECU 10 is an electronic control unit that performs various processes related to autonomous driving assistance. For example, it continuously detects the vehicle's current position, the driving lane, and the positions of surrounding obstacles, and controls the vehicle such as the steering system, drive system, and brakes to travel along the generated driving trajectory at a speed according to the same generated speed plan. In particular, in the case of parking assistance and exiting a parking space assistance, it uses the detection results of the aforementioned front camera 6, rear camera 7, side cameras 8A and 8B, and ultrasonic sensors 9A to 9L to confirm the parking space and its surrounding conditions, and calculates the forward or backward trajectory indicated by the passenger, and controls the vehicle to enter or exit the parking space along the calculated trajectory. In addition, the scenery (real view) around the vehicle can be displayed on the LCD 4, and if there are warning objects such as pedestrians around the vehicle, a warning image indicating the presence of the warning object is overlaid at the position of the warning object in the scenery. The driver assistance ECU 10 connects to the aforementioned operating unit 3, LCD display 4, speaker 5, front camera 6, rear camera 7, side cameras 8A and 8B, and ultrasonic sensors 9A to 9L via a vehicle network such as CAN. It also connects to various sensors mounted on vehicle 2, such as vehicle speed sensor, acceleration sensor, gyroscope sensor, steering mechanism sensor, and shift position sensor, as well as navigation devices that function as in-vehicle systems. The detailed structure of the driver assistance ECU 10 will be described later.

[0048] In addition, Figure 1 In addition to the structural components shown, vehicle 2 also has basic structural components that serve as vehicle 2, but only the structures related to the control of autonomous driving assistance and the control associated with these structures will be described.

[0049] Next, the driving assistance device 1 of the above-mentioned vehicle 2, especially the driving assistance ECU 10, will be described in detail. Figure 4 This is a block diagram showing the structure of the driving assistance device 1 in this embodiment.

[0050] like Figure 4 As shown, the driving assistance ECU (electronic control unit) 10 is an electronic control unit that performs overall control of the driving assistance device 1. It includes: a CPU 31, which serves as a computing and control unit; and a RAM 32, which is used as working memory when the CPU 31 performs various calculations and stores driving trajectory data such as the calculated driving trajectory. In addition to the control program, it also has a driving assistance processing program (described later) recorded in the control program. Figure 3The ECU 10 includes internal storage devices such as ROM 33 and flash memory 34 storing programs read from ROM 33. Furthermore, the ECU 10 performs various functions as processing algorithms. For example, when parking assistance or exit assistance is initiated, if an obstacle located to the side of vehicle 2 is detected by ultrasonic sensors 9E to 9H, approach to the detected obstacle to the side of vehicle 2 is restricted during the period from the initiation of parking assistance or exit assistance until a predetermined condition is met.

[0051] In addition, the driver assistance ECU 10 is also connected to various sensors 36 used to detect vehicle movements, such as vehicle speed sensors, acceleration sensors, gyroscope sensors, steering system sensors, and shift position sensors, as well as various drive units 37 of the vehicle, such as steering system, brakes, accelerator, and transmission. Based on the detection results of these sensors 36, the current movement of the vehicle is detected, and autonomous driving assistance for the vehicle 2 is implemented by controlling each drive unit 37. Specific aspects of autonomous driving assistance include, for example, continuously detecting the vehicle's current position, the driving lane, and the positions of surrounding obstacles, and controlling the steering system, drive unit, and brakes while driving along the generated trajectory at a speed according to the same generated speed plan. However, it is also possible to perform only automatic steering operations, while controlling the drive unit and brakes based on manual operation.

[0052] In addition, the driver assistance ECU 10 is connected to a radio wave receiver 38, which transmits and receives radio waves with a remote control 39, an operating terminal held by the passenger. The radio wave receiver 38 is a device for receiving radio waves emitted from the remote control 39. The remote control 39 has, for example, two buttons, "forward" and "backward," as operating buttons. The driver assistance ECU 10 uses the radio wave receiver 38 to detect which of the two buttons the passenger has operated. In particular, in this embodiment, when performing vehicle parking assistance and exiting parking assistance, the user indicates the vehicle's direction of travel (the direction from the parking space when exiting, and the direction to the parking space when parking) using the remote control 39 to indicate "forward" or "backward." Furthermore, the remote control can also be used as an electronic key to unlock the door. Alternatively, a smartphone held by the passenger, which is communicatively connected to the vehicle 2, can also be used as the remote control 39.

[0053] Additionally, the flash memory 34 contains vehicle information DB35, which stores various information related to vehicle 2. This includes, for example, the locations of cameras and ultrasonic sensors 9A-9L installed on vehicle 2 (height from the ground, left-right position), detection axes (optical axes for cameras), overall length, vehicle width, wheelbase, and minimum turning radius. This information is pre-entered by passengers or personnel from the vehicle manufacturer.

[0054] Next, based on Figure 5 The driving assistance processing procedure executed by the driving assistance ECU 10 in the driving assistance device 1 having the above structure will be described. Figure 5 This is a flowchart of the driving assistance processing procedure in this embodiment. Here, the driving assistance processing procedure is executed after the ACC power (accessory power supply) of vehicle 2 is turned on, and is one type of automatic driving assistance, particularly for implementing parking assistance and parking exit assistance. Furthermore, the following... Figure 5 The program shown in the flowchart is stored in RAM32 or ROM33 of the driving assistance device 1 and executed by CPU31.

[0055] First, in step (hereinafter referred to as S) 1, the CPU 31 determines whether to start either parking assistance or exit assistance. In this embodiment, the CPU 31 determines to start either parking assistance or exit assistance if the radio wave receiver 38 detects that the passenger has operated either "forward" or "backward" using the remote control 39. The passenger may be in the vehicle or have already disembarked, but in the following explanation, parking assistance and exit assistance will be performed under the premise that the passenger has already disembarked from the vehicle.

[0056] In this embodiment, when parking or exiting a parking space, the user does not specify whether it is parking or exiting, but instructs the vehicle to move forward or backward. For example, when exiting a parking space with the vehicle parked forward, the instruction is "forward," and when exiting a parking space with the vehicle parked backward, the instruction is "backward." On the other hand, when moving the vehicle forward and parking it in a parking space, the instruction is "forward," and when moving the vehicle backward and parking it in a parking space, the instruction is "backward." Furthermore, the driving assistance device 1 automatically moves the vehicle in the indicated direction to ultimately park or exit the parking space. That is, in this embodiment, the driving assistance device 1 does not distinguish between parking assistance and exiting assistance, but performs the same control from S2 onwards.

[0057] However, the conditions for starting parking assistance and exit assistance are not limited to the operation of the remote control 39 mentioned above. For example, it can also be based on the condition that the occupant operates the control unit 3 located inside the vehicle while seated in the vehicle. In addition, when the vehicle is detected to have entered the parking lot, parking assistance can be automatically started when the set destination is determined to have been reached or when the vehicle is approaching the parking lot. Exit assistance can also be started when the ignition switch is turned on.

[0058] Then, if it is determined that either parking assistance or exit assistance has been started (S1: "Yes"), proceed to S2. Conversely, if it is determined that either parking assistance or exit assistance has been started (S1: "No"), the driving assistance process ends.

[0059] In S2, at the current moment when parking assistance or exit assistance for the vehicle begins, the CPU31 determines whether any obstacle has been detected by the ultrasonic sensors 9A to 9L, especially the ultrasonic sensors 9E to 9H (side sonar) which are installed on the side of the vehicle and have the side of the vehicle as their detection range. In particular, it is preferable to also consider that the distance to the detected obstacle, i.e., the ranging distance, is within a predetermined detection distance as a condition.

[0060] Here, as described above, the ultrasonic sensors 9A to 9L detect objects that reflect the ultrasonic waves by emitting ultrasonic waves as detection waves around the vehicle 2 and receiving the reflected waves after the emitted detection waves are reflected by objects located around the vehicle. Figure 2 , Figure 3 In this embodiment, although multiple ultrasonic sensors are installed on the vehicle, the range in which they can transmit detection waves is limited. Therefore, even if the detection waves are reflected by obstacles, the reflected waves can only be received when reflected by obstacles located at a relatively close distance (e.g., within 5m) from the ultrasonic sensors 9A to 9L. Furthermore, reflected waves cannot be received from obstacles located at a position significantly separated from the detection axis of the ultrasonic sensors in the left-right direction. Specifically, as... Figure 6 As shown, the detection ranges 41 to 52, which can detect obstacles using ultrasonic sensors 9A to 9L, are approximately elliptical in shape. As mentioned above, the detection ranges 41 to 52 are limited, and the obstacles that can be detected using ultrasonic sensors 9A to 9L are essentially limited to those located relatively close to the vehicle. In particular, to detect obstacles located to the side of the vehicle, the obstacle needs to be within the detection ranges 45 to 48, requiring the vehicle to be positioned close to the obstacle being detected.

[0061] Therefore, in S2 above, detecting an obstacle by ultrasonic sensors 9E to 9H means that the obstacle is located within any one of the detection ranges 45 to 48, the reflected wave reflected by the obstacle is received, and the distance from the sensor to the obstacle, i.e., the ranging distance, can be determined. Furthermore, the ranging distance is calculated based on the time from sending the detection wave to receiving the reflected wave. Additionally, the detection distance, as an additional determination condition in S2 above, is, for example, 40 cm, but this distance can be appropriately changed. However, it is preferable to have a distance longer than the allowable distance (the allowable distance to the obstacle when generating the driving trajectory) described later.

[0062] Here, as described later, ultrasonic sensors 9E to 9H can determine the specific position of an object by using triangulation—which utilizes the distance measured at the previous position, the distance measured at the current position, and the distance traveled between them—as the vehicle moves. However, at time S2, since the vehicle has not yet begun to move, the aforementioned triangulation is not valid. Furthermore, as... Figure 3 As shown, the ultrasonic sensors 9E to 9H are arranged separately and cannot receive indirect waves. Therefore, triangulation using indirect waves is not valid, and the exact location of the obstacle cannot be determined. Therefore, in S2 above, obstacle detection is performed using ultrasonic sensors 9E to 9H based solely on direct waves. Furthermore, while the distance to the obstacle can be determined in detection based solely on direct waves, the exact location and shape of the obstacle are difficult to ascertain.

[0063] Furthermore, if it is determined that an obstacle is detected by the ultrasonic sensors 9E to 9H, and the distance to the detected obstacle, i.e., the ranging distance, is within the prescribed detection distance (S2: "Yes"), the process proceeds to S3. Additionally, obstacles located to the side of vehicle 2 that are determined to be detected by the ultrasonic sensors 9E to 9H in S2 above are hereinafter referred to as side obstacles. Conversely, if it is determined that no obstacle is detected by the ultrasonic sensors 9E to 9H, or even if an obstacle is detected but the distance to the obstacle, i.e., the ranging distance, is outside the prescribed detection distance (S2: "No"), the process proceeds to S7.

[0064] In S3, CPU 31 calculates a travel trajectory for moving from the vehicle's current position in the direction specified by the passenger. As described above, the passenger can use remote control 39 to indicate either "forward" or "backward". When "forward" is indicated, a travel trajectory for moving forward from the vehicle's current position is calculated; when "backward" is indicated, a travel trajectory for moving backward from the vehicle's current position is calculated.

[0065] Furthermore, in generating the vehicle's trajectory, the trajectory is essentially generated based on obstacle detection results from the camera and ultrasonic sensors 9A-9L. As mentioned above, the ultrasonic sensors 9A-9L are capable of detecting obstacles located within the detection range 41-52 (…). Figure 6 While triangulation can be used to determine the precise location, it is not feasible to use the ultrasonic sensors 9E-9H, which have a detection range to the sides of the vehicle, at the moment when parking assistance or exit assistance begins. On the other hand, in obstacle detection performed by the front camera 6, rear camera 7, and side cameras 8A and 8B, obstacles can be detected by performing image recognition on the images captured by each camera. The obstacles to be detected are objects that impede vehicle movement, and are not limited to moving or stationary objects. Examples include pedestrians, other vehicles, and walls. Furthermore, the process for detecting obstacles from the captured images includes, for example, brightness correction based on the brightness difference between the road surface and obstacles on the road surface, followed by binarization to separate obstacles from the image, geometric processing to correct distortion, and smoothing to remove noise from the image, which enables the detection of the boundary lines between the road surface and obstacles. Additionally, known template matching or feature point detection methods can be used to detect the type of obstacle. Moreover, the image recognition processing performed on the captured images is not limited to the examples described above; machine learning can also be used, for example. Furthermore, the obstacle detection performed by the aforementioned camera has a wider detection range compared to obstacle detection performed by ultrasonic sensors 9A-9L. Even obstacles located far from the vehicle can be detected as obstacles as long as they are included in the captured image. On the other hand, compared to ultrasonic sensors 9A-9L, it suffers from lower detection accuracy.

[0066] Here, in generating the vehicle's trajectory, the obstacle detection performed by the aforementioned cameras and ultrasonic sensors 9A-9L is based on the premise that, when an obstacle is detected around the vehicle, a trajectory is generated where the distance from the vehicle to the obstacle is always maintained at or above a predetermined allowable distance (e.g., 20cm). For example, as... Figure 7 As shown, in the case of exiting a vehicle parked in garage 55, if an obstacle 56 is detected in front of the vehicle's direction of travel, a driving trajectory 57 that turns slightly to the right relative to straight travel is generated in order to maintain a safe distance from the obstacle 56. The turning trajectory can be a spiral or an arc, but it is generated based on vehicle information (wheelbase, etc.) stored in vehicle information DB35, resulting in a curve that the vehicle can trace. Furthermore, if a driving trajectory that ensures a safe distance from the obstacle cannot be generated, such as when an obstacle is directly in front of the vehicle's direction of travel, the assistance is stopped.

[0067] As mentioned above, cameras are also used in obstacle detection, but the detection accuracy of cameras is lower than that of ultrasonic sensors 9A-9L, thus potentially leading to false detections of the presence or location of obstacles. For example... Figure 8 As shown, the case of false detection of an obstacle 56 at a location that does not actually exist is also considered. In this case, especially as... Figure 8 As shown, if the walls of the garage 55, which act as obstacles, are present on the left and right sides of the vehicle, and a turning trajectory 57 is generated immediately after the start of the assist, the vehicle will approach the walls of the garage 55 to avoid non-existent obstacles 56—a maneuver incomprehensible to the occupants, causing confusion and unease. Furthermore, especially in situations like… Figure 9 In the case of "reverse" exiting the parking space as shown, if a turning trajectory is generated from the beginning, the distance between the front of the vehicle and the wall of garage 55 will be close due to the outer wheel difference. Subsequently, it may be impossible to generate a trajectory that ensures a distance greater than the allowable distance between the vehicle and the wall of garage 55 (resulting in a state where the trajectory cannot be corrected and the vehicle cannot move), causing the assist to be forcibly terminated. Although the explanation is omitted, the situation caused by the inner wheel difference when moving forward may also occur.

[0068] Therefore, in this embodiment, in order to avoid Figure 8 and Figure 9 In the situation described above, during the generation of the driving trajectory in S3, if a lateral obstacle is detected by ultrasonic sensors 9E to 9H at the moment when the vehicle's parking assistance or exit assistance begins (S2: "Yes"), then approach to the detected lateral obstacle is restricted from the moment the vehicle's parking assistance or exit assistance begins until the condition in S5 is met. That is, at the moment when... Figure 10 When the parking assist or exit assist function of the vehicle shown is performed with walls of the garage 55 on both sides, a driving trajectory is generated where the distances D1 to the right wall and D2 to the left wall detected by ultrasonic sensors 9E-9H are not shorter than the current distance. This is a driving trajectory 57 that exits the garage 55 by traveling straight between the walls. Specifically, even if an obstacle (different from a side obstacle) is detected in the vehicle's direction of travel by sensors or cameras with a detection range in the vehicle's direction of travel, approach to the side obstacle is restricted. Furthermore, the sensors or cameras with a detection range in the vehicle's direction of travel refer to, if the vehicle 2 moves forward, ultrasonic sensors 9A-9D or a front camera 6 with a detection range in front of the vehicle. On the other hand, if the vehicle 2 moves backward, ultrasonic sensors 9I-9L or a rear camera 7 with a detection range in rear of the vehicle. Furthermore, in... Figure 10In the example shown, if the vehicle continues to travel straight, it will come into contact with obstacle 56 in the direction of travel. However, as will be described later, the restriction is lifted after a certain period of traveling straight, thus ultimately generating a driving trajectory 57 (S7) that turns to avoid obstacle 56.

[0069] also, Figure 10 This is an example of a situation where, at the moment when parking assist or exit assist is initiated, the walls of garage 55, which act as lateral obstacles, are detected on the left and right sides of the vehicle. For example, when there is only one wall, in addition to the straight driving trajectory, a trajectory that turns away from the wall is also allowed to be generated.

[0070] Then, in S4, CPU31 begins parking assistance or exiting-the-garage assistance according to the driving trajectory calculated in S3 above. Specifically, it continuously detects the current position of the vehicle and automatically controls the steering device, drive source, brakes, and other vehicle functions along the generated driving trajectory at a specified speed.

[0071] Furthermore, the processing of S3 and S4 is repeated every predetermined distance unit (e.g., 50cm) before the determination condition of S5 described later is met. That is, every predetermined distance unit is traveled, a driving trajectory that restricts approach to lateral obstacles is generated, and the control of driving the vehicle is repeated according to the generated driving trajectory.

[0072] Next, in S5, CPU31 determines whether at least one of the following conditions (A) and (B) is true.

[0073] (A) For lateral obstacles detected by ultrasonic sensors 9E to 9H at the moment when the vehicle starts parking assistance or exit assistance, the position can be determined by triangulation.

[0074] (B) The vehicle has traveled a specified distance (e.g., 1m) since the start of the parking assist or exit assist.

[0075] Furthermore, in this embodiment, it is determined whether at least one of conditions (A) and (B) is true, but it is also possible to determine whether both conditions are true. Alternatively, it is possible to determine whether either condition (A) or (B) is true.

[0076] Then, after determining that at least one of conditions (A) and (B) has been met (S5: "Yes"), the restriction on approaching the lateral obstacle set in S3 above is lifted (S6).

[0077] Then, in S7, CPU31 calculates a driving trajectory for moving from the vehicle's current position towards the direction of travel specified by the passenger. This is essentially the same process as S3 described above, but the restriction on approaching lateral obstacles detected by ultrasonic sensors 9E-9H at the start of parking or exit assistance is removed when generating the driving trajectory. However, although the approach restriction is removed, the condition of maintaining a distance of at least 20 cm from lateral obstacles detected at the start of assistance (including obstacles detected later) is still included.

[0078] Here, we will explain condition (A) above in more detail. When using the detection results of ultrasonic sensors 9E, 9F or ultrasonic sensors 9G, 9H located on the side of vehicle 2 to determine an obstacle, the exact location of the obstacle can be determined by using triangulation, which utilizes the distance measured at the previous position, the distance measured at the current position, and the distance moved between them, through vehicle movement. Specifically, firstly, as... Figure 11 As shown, CPU31 acquires various vehicle information at a specific time after the reflected wave was received by ultrasonic sensors 9E, 9F or 9G, 9H at the previous location. Specifically, the acquired vehicle information includes, for example, vehicle speed v, the vehicle's current position coordinates (x1, y1), and vehicle orientation. 1. This information is determined using sensors such as vehicle speed sensors, gyroscope sensors, and steering system sensors. Additionally, the count value t1 of a timer used to determine the timing of the received reflected wave at the previous position is also acquired. Next, the CPU 31 similarly acquires various vehicle information regarding the timing of the received reflected wave at the current position by ultrasonic sensors 9E, 9F, or ultrasonic sensors 9G, 9H. Specifically, the acquired vehicle information includes, as with the previous position, vehicle speed v (since the transmission interval of the probe wave is short, it is considered that the vehicle speed does not change), the vehicle's current position coordinates (x2, y2), and vehicle orientation. 2. The timer's count value t2, etc. Furthermore, if no reflected wave is received within a specified time (e.g., until the timing of the next ultrasonic wave transmission) from the time the ultrasonic wave is transmitted, it is determined that an obstacle cannot be detected. Furthermore, the timing of receiving the probe wave at the previous position and the current position is basically continuous in time sequence, but it can be discontinuous with intervals. Then, the CPU 31 calculates the ranging distance based on the time interval from transmitting the probe wave to receiving the reflected wave reflected by the object at the previous position and the current position, respectively, and stores the calculated ranging distance in association with the vehicle information acquired above. Furthermore, as... Figure 11As shown, the ranging distance calculated by the ultrasonic sensor is the distance L1 from the sensor position S of vehicle 2 at the previous position to the reflection point P of the reflected wave, and the distance L2 from the sensor position S' of vehicle 2 at the current position to the reflection point P of the reflected wave. Then, the CPU 31 calculates the distance Δy that the vehicle has traveled from the previous position to the current position based on the vehicle speed v during the ranging period. Then, considering the vehicle information at the previous position and the vehicle information at the current position, the coordinates (x3, y3) of the reflection point P of the reflected wave are calculated using triangulation that uses the ranging distance L1 at the previous position, the ranging distance L2 at the current position, and the distance Δy between them. Furthermore, the above calculation example is one example, and the coordinates (x3, y3) of the reflection point P can be calculated using other methods. Then, the CPU 31 stores the calculated coordinates (x3, y3) of the reflection point P as point data in the flash memory 34 or the like. The coordinates (x3, y3) of the reflection point P are used to determine the position of the obstacle (more specifically, the position of the surface that forms the shape of the obstacle), such as... Figure 12 As shown, by connecting the point data of location P, the shape (surface) of the obstacle can also be accurately determined.

[0079] Therefore, in S5 above, the condition (A) is satisfied when, at the moment the vehicle's parking assistance or exit assistance begins, the ultrasonic sensors 9E to 9H only detect nearby lateral obstacles (e.g., in...). Figure 12 In the example shown, the wall of garage 55 becomes a structure whose precise location and shape can be determined using triangulation. If, after this state, we assume... Figure 12 The system detects obstacle 56 and generates a trajectory to avoid it, also preventing the vehicle from turning immediately after the assist is activated. Additionally, as shown... Figure 8 As shown, even if a non-existent obstacle 56 is detected due to a false detection by the camera, a trajectory approaching the wall of the garage 55 will not be generated immediately after the assistance begins, thus preventing occupants from feeling uneasy. Furthermore, the driving trajectory can be generated with a certain degree of accuracy based on the position and shape of the garage 55 walls detected on the left and right sides of the vehicle from the moment the assistance begins, thereby preventing situations such as... Figure 9 As shown, the trajectory cannot be corrected and the device remains in an immobile state, causing the assist to be forcibly terminated.

[0080] Furthermore, in this embodiment, multiple ultrasonic sensors 9E to 9H, whose detection range is the side of the vehicle, are installed at different locations on the vehicle. However, regarding condition (A) above, if a side obstacle is detected by the ultrasonic sensors 9E to 9H installed on the vehicle at the moment when parking assistance or exit assistance for the vehicle begins, the ultrasonic sensor located on the side closest to the vehicle's direction of travel among the multiple ultrasonic sensors 9E to 9H that detected the side obstacle (e.g., in...) Figure 12 In the example shown, ultrasonic sensors 9E and 9G are used as the target, preferably with the condition that the position of lateral obstacles can be determined using triangulation that uses ranging distance. This is because, in the generation of the vehicle's driving trajectory, determining the position of lateral obstacles located on the side of the vehicle's direction of travel (e.g., in...) Figure 12 In the example shown, the shape near the entrance of garage 55 is more important than determining the lateral obstacles located in the opposite direction of the vehicle's travel.

[0081] Regarding condition (A) above, all ultrasonic sensors that detect lateral obstacles can also be used at the moment when the vehicle's parking assist or exit assist begins (e.g., in...). Figure 12 The example shown uses ultrasonic sensors 9E to 9H as the object, and the condition is that the position of the side obstacle can be determined by using triangulation that uses the distance measurement.

[0082] On the other hand, regarding condition (B) of S5 above, for example, due to certain reasons, accompanied by Figure 11 The triangulation of vehicle movement described in the text is always invalid. If the vehicle continues to travel straight, it may be unable to avoid obstacles in the direction of travel that it wants to avoid. Figure 12 The obstacle 56 shown is thus set to limit the maximum distance a vehicle can move to approach a lateral obstacle. That is, even if triangulation accompanying vehicle movement fails, the limitation on approaching a lateral obstacle detected by ultrasonic sensors 9E-9H at the moment the vehicle has traveled a predetermined distance since the start of the assist is lifted, and a driving trajectory is generated. Furthermore, if a predetermined distance (e.g., 1m) has been traveled since the start of parking assist or exit assist, even if... Figure 12 The system detects obstacle 56 and generates a turning trajectory afterward, which also prevents the generation of a turning trajectory immediately after the assist begins. Additionally, as shown... Figure 8 As shown, even if a non-existent obstacle 56 is detected due to a false detection by the camera, a trajectory approaching the wall of the garage 55 will not be generated immediately after the assistance begins, thus avoiding confusion and anxiety for the occupants. Furthermore, in this embodiment, the specified distance is set to 1m, but it can also be set to a distance beyond 1m.

[0083] Subsequently, in S8, CPU31 begins parking assistance or exiting-the-garage assistance according to the driving trajectory generated in S7. Specifically, it continuously detects the current position of the vehicle and automatically controls the steering device, drive source, brakes, and other vehicle functions in a manner that allows the vehicle to travel along the generated driving trajectory at a specified speed.

[0084] The results of the above S3 to S8 processes are as follows: Figure 10 As shown, vehicle 2 initially travels straight for a certain period without approaching the walls of garage 55, which are detected on the left and right sides at the start of the assistance (e.g., a straight trajectory, but if there is only one wall, it could also be a trajectory turning in the direction of departure). Then, if obstacle 56 is detected in the vehicle's direction of travel when using the camera and ultrasonic sensors 9A-9L to detect obstacles, the restriction on approaching the walls of garage 55 is lifted. Figure 12 As shown, a driving trajectory is generated that maintains the distance from vehicle 2 to obstacle 56 and the distance to the wall of garage 55 within a specified allowable distance (e.g., 20cm). For example, as... Figure 12 As shown, in order to avoid obstacle 56, a trajectory that turns to the right is generated.

[0085] Furthermore, the processing of S7 and S8 is repeated every predetermined distance unit (e.g., 50cm) before parking assistance or exit assistance is completed. That is, every predetermined distance unit, a driving trajectory is generated based on the obstacle detection results, and the vehicle driving control is repeated according to the generated driving trajectory.

[0086] The conditions for completing parking assistance or exit assistance can be either that a predetermined distance has been traveled since the start of assistance, or that the passenger indicates the end of assistance using the remote control. For exit assistance, the condition can also be that no more obstacles are detected around the vehicle. Furthermore, for parking assistance, the condition can be that the vehicle can no longer move further in the direction indicated by the passenger (e.g., a wall is detected in the direction of travel).

[0087] In addition, in this embodiment, such as Figure 6 As shown, multiple ultrasonic sensors 9E to 9H, whose detection range is the side of vehicle 2, are installed at different locations on vehicle 2. Furthermore, when parking assistance or exit assistance is initiated, if at least one of the multiple ultrasonic sensors 9E to 9H installed on the vehicle detects a side obstacle, in step S3 above, it is preferable to generate a driving trajectory that restricts approach to the side obstacle, based on the side obstacle detected by all the ultrasonic sensors that detected it.

[0088] Here, if in S3 above only a driving trajectory is generated that restricts approach to lateral obstacles detected by the ultrasonic sensor on the side closest to the vehicle's direction of travel, the following problem arises. That is, if... Figure 13 As shown, when the vehicle begins exit assistance from part of garage 55, the ultrasonic sensors closest to the direction of travel are ultrasonic sensor 9F and ultrasonic sensor 9H. However, since ultrasonic sensor 9F and ultrasonic sensor 9H do not detect any lateral obstacles at the start of assistance, the restrictions in S3 are not applied, and the driving trajectory in S7 is generated immediately after assistance begins. The result is, for example, as... Figure 13 As shown, when an obstacle 56 is detected in the vehicle's direction of travel, a driving trajectory 57 is generated immediately after the assist begins to turn in order to avoid the obstacle 56. As a result, the distance between the front of the vehicle and the wall of the garage 55 becomes close due to the outer wheel difference, and it may then be impossible to generate a driving trajectory that ensures a distance of more than the allowable distance between the vehicle and the wall of the garage 55 (becoming a state where the trajectory cannot be corrected and the vehicle cannot move), causing the assist to be forcibly terminated.

[0089] On the other hand, if the lateral obstacles detected by all ultrasonic sensors in S3 described above are taken as the object, and a driving trajectory that restricts approach to the lateral obstacles is generated, the above problem can be solved. That is, as... Figure 14 As shown, even when the exit assist begins while part of the vehicle has exited the garage 55, the ultrasonic sensors 9E and 9G, located in the opposite direction to the direction of travel, detect the wall of the garage 55 as a lateral obstacle at the moment the assist begins. Therefore, immediately after the assist begins, the driving trajectory that restricts approach to the wall of the garage 55 as described in S3 above is generated. The result, for example, is as follows: Figure 14 As shown, even if an obstacle 56 is detected in the direction of the vehicle's travel, a driving trajectory that restricts the approach to the wall of the garage 55 will be generated before the conditions of S5 are met. Therefore, a driving trajectory 57 that turns to avoid the obstacle 56 will not be generated immediately after the start of the assist, but will be generated only after the conditions of S5 are met.

[0090] Furthermore, in the explanation up to this point, in particular, the following phrases were used. Figures 7-14 An example of assisting a vehicle out of a parking space has been given, but it also has the same effect when assisting a vehicle in parking. For example, in Figure 15 In the context of parking assistance that moves the vehicle forward and stops within the garage 55, the situation where an obstacle 56 is detected to the side of the vehicle at the moment parking assistance begins is explained. Figure 15In the example shown, obstacle 56 is equivalent to a lateral obstacle, not garage 55. In this case, the following problem exists: if approaching the obstacle is not restricted during the generation of the driving trajectory in S3, the vehicle will generate a left-turn driving trajectory 57 immediately after the start of the parking assist in order to align with the entrance to garage 55 detected by a camera or the like. As described above, in this embodiment, during the generation of the driving trajectory in S3, since approaching the obstacle 56 detected during the period from the start of the vehicle's parking assist until the conditions of S5 are met, the generated trajectory is as follows... Figure 16 The driving trajectory 57 shown is a straight path heading towards garage 55. Then, for example, the detailed location of obstacle 56 is detected by triangulation (or a prescribed distance is traveled), and the restriction is lifted after the condition of S5 is met. Then, the final driving trajectory 57 (S7) is generated, which turns to enter the entrance of garage 55.

[0091] As detailed above, according to the driving assistance device 1 of this embodiment and the computer program executed by the driving assistance device 1, obstacles are detected based on the detection results of the ultrasonic sensors 9E to 9H provided with the vehicle during parking assistance or parking exit assistance. Furthermore, multiple ultrasonic sensors 9E to 9H are provided on the side of the vehicle 2 in a positional relationship where they cannot receive indirect waves from each other. When parking assistance or parking exit assistance begins, if a side obstacle is detected by the ultrasonic sensors 9E to 9H on the side of the vehicle, approach to the detected side obstacle is restricted during the period from the start of parking assistance or parking exit assistance until a predetermined condition is met (S3, S4). Therefore, even if the obstacle detection accuracy decreases after assistance begins, it is possible to prevent actions that approach obstacles based on low-accuracy detection results. Furthermore, actions that are incomprehensible to the user, such as approaching other obstacles to avoid non-existent obstacles, will not occur, thus avoiding confusion and anxiety for the user. Additionally, it will not lead to a situation where the trajectory cannot be corrected afterward during parking assistance and parking exit assistance.

[0092] Furthermore, in obstacle detection based on ultrasonic sensors 9E to 9H, the position of the obstacle can be determined by triangulation, which uses the distance measured from a plurality of different vehicle positions along with the movement of the vehicle and the distance the vehicle moves between those distances. The specified condition is that the position of a side obstacle detected by the distance sensor at the moment when the vehicle starts parking assistance or exit assistance can be determined by triangulation (S5). Therefore, after the assistance starts, the triangulation is established, and the detection accuracy of the side obstacle can be fully guaranteed, so the vehicle parking assistance or exit assistance can be performed with confidence in the detection results of the side obstacle.

[0093] Furthermore, the specified condition is that the vehicle has traveled a specified distance since the start of parking assistance or exit assistance (S5). Here, if the aforementioned triangulation cannot be established for some reason, and the establishment of triangulation is used as the specified condition, the vehicle will continue to travel straight, potentially making it impossible to avoid the obstacle it intends to avoid. Figure 12 The obstacle shown is 56), but by considering the travel distance, the above situation can be avoided.

[0094] Furthermore, when parking assistance or exit assistance is initiated, if a side obstacle is detected by at least one of the multiple ultrasonic sensors 9E to 9H installed on the vehicle, the approach to the obstacle is restricted based on the obstacle detected by all the ultrasonic sensors that detected the side obstacle (S3). Therefore, by not limiting the object to a specific ultrasonic sensor, it is also possible to restrict the approach to side obstacles that are outside the detection range of the sonar on the direction of travel.

[0095] Furthermore, when parking assistance or exit assistance for vehicle 2 is initiated, if a lateral obstacle is detected by ultrasonic sensors 9E to 9H, even if a sensor or camera with a detection range covering the direction of travel of vehicle 2 detects an obstacle in addition to the lateral obstacle in the direction of travel of vehicle 2, approach to the lateral obstacle is restricted from the time the parking assistance or exit assistance for vehicle 2 is initiated until the prescribed conditions are met. Therefore, even if there is an obstacle in the direction of travel of the vehicle, approaching the lateral obstacle can be prevented until the prescribed conditions are met.

[0096] [Postscript]

[0097] The following inventions are disclosed in the above embodiments. In the following description, reference numerals used in the drawings are enclosed in parentheses for reference to the names and representations of the corresponding structures in the embodiments. However, the structural components of each invention are not limited to these annotations.

[0098] (Invention A) The driving assistance device (1) according to claim 2, wherein, The distance measuring sensors (9E to 9H) are provided in multiple locations at different positions on the vehicle (2). The specified condition is that when the side obstacle is detected by the multiple distance measuring sensors provided on the vehicle at the moment when the vehicle starts parking assistance or parking assistance, the position of the side obstacle can be determined by the triangulation of the distance measuring distance of the distance measuring sensor closest to the vehicle's direction of travel among the multiple distance measuring sensors that detected the side obstacle.

[0099] Therefore, at least under the condition that the detection accuracy of obstacles located on the side of the vehicle's direction of travel can be fully guaranteed, the detection results of obstacles can be trusted to assist the vehicle in parking or exiting the parking space.

[0100] (Invention B) According to claim 1, the driving assistance device (1), wherein, When assisting with parking or exiting a vehicle (2), the detection results of the distance measuring sensor (9E-9H) are used to generate the future driving trajectory (57) of the vehicle along the direction of travel. Control the vehicle to move according to the generated driving trajectory. In the generation of the driving trajectory. If the lateral obstacle is detected by the ranging sensor at the moment the vehicle's parking assist or exit assist begins, a driving trajectory is generated that restricts approach to the lateral obstacle during the period from the start of the vehicle's parking assist or exit assist until a predetermined condition is met.

[0101] Therefore, even when obstacle detection accuracy is low after the assistance begins, it prevents the generation of a driving trajectory that approaches obstacles based on low-accuracy detection results. Furthermore, it avoids driving trajectories that are incomprehensible to the user, such as approaching other obstacles to avoid non-existent ones, thus preventing user confusion and anxiety. Additionally, it prevents situations where the trajectory in parking assistance or exit assistance cannot be corrected later.

[0102] (Invention C) The driving assistance device (1) according to invention B, wherein, Generating a driving trajectory (57) that restricts approach to the lateral obstacle means that the lateral obstacle is detected by the ranging sensor within a specified detection distance from the vehicle at the moment when the vehicle (2) begins parking assistance or exit assistance. The detection distance is longer than the distance from the vehicle to the obstacle allowed when the driving trajectory was generated.

[0103] Therefore, for any lateral obstacles detected at the start of parking assist or exit assist, the distance to the obstacle is maintained longer than the permissible approach distance, and the subsequent driving trajectory is generated. As a result, a situation is avoided where the distance to the lateral obstacle exceeds the permissible range, making it impossible to correct the trajectory.

[0104] Furthermore, the present invention is not limited to the above-described embodiments, and various modifications and variations can be made without departing from the spirit of the present invention.

[0105] For example, in this embodiment, parking assistance and exit assistance are initiated by a passenger outside the vehicle using remote control 39 to control the vehicle's direction of travel. However, the conditions for initiating parking assistance and exit assistance are not limited to the above example; parking assistance and exit assistance can also be performed while the passenger is in the vehicle.

[0106] Furthermore, in this embodiment, S2 determines whether an obstacle is detected by ultrasonic sensors 9E to 9H, particularly those with a detection range to the side of the vehicle, among the ultrasonic sensors 9A to 9L. However, it is also possible to determine whether an obstacle is detected by ultrasonic sensors other than ultrasonic sensors 9E to 9H. In this case, if an obstacle is detected around the vehicle other than to the side, the approach restriction described in S3 can be applied to that obstacle.

[0107] Furthermore, in this embodiment, as a parking assistance and exiting assistance for the vehicle, as follows: Figures 7 to 16 The parking assistance for parking a vehicle in an enclosed garage 55 and the exit assistance for exiting the garage 55 are illustrated as examples, but the same principles apply to parking assistance and exit assistance for parallel parking of vehicles in a typical flat parking lot. Furthermore, the same principles apply to parking assistance and exit assistance for longitudinal parking.

[0108] Furthermore, in this embodiment, the driving assistance ECU 10 of the driving assistance device 1 is configured to execute the driving assistance processing program ( Figure 5 The processing can be handled by the LCD 4 control unit, the vehicle control ECU, the navigation device control unit, or other vehicle-mounted devices.

Claims

1. A driving assistance device, in the context of parking assistance or exiting a parking space, detects obstacles based on the detection results of a distance measuring sensor present in the vehicle, wherein... Multiple ranging sensors are arranged on the side of the vehicle in a positional relationship where they cannot receive indirect waves from each other. When the parking assist or exit assist of the vehicle is initiated, if the ranging sensor detects a lateral obstacle as an obstacle on the side of the vehicle, the approach to the lateral obstacle is restricted for the period from the initiation of the parking assist or exit assist until the predetermined conditions are met.

2. The driving assistance device according to claim 1, wherein, In obstacle detection based on the ranging sensor, the position of the obstacle can be determined using triangulation. This triangulation uses ranging distances from a plurality of different vehicle positions accompanying the movement of the vehicle, and the distance the vehicle has moved between the plurality of vehicle positions. The specified condition is that the position of the lateral obstacle detected by the ranging sensor at the moment when the vehicle's parking assistance or exit assistance begins can be determined using the triangulation.

3. The driving assistance device according to claim 1, wherein, The specified condition is that the vehicle has traveled a specified distance since the start of the parking assistance or exit assistance.

4. The driving assistance device according to claim 1, wherein, When parking assistance or exit assistance of the vehicle is initiated, if a lateral obstacle is detected by at least one of the plurality of distance sensors provided in the vehicle, approach to the lateral obstacle is restricted based on the lateral obstacle detected by all the distance sensors that detected the lateral obstacle.

5. The driving assistance device according to claim 1, wherein, When the vehicle's parking assist or exit assist is initiated, and the lateral obstacle is detected by the ranging sensor... Even if a sensor or camera with the vehicle's direction of travel as its detection range detects an obstacle in the direction of travel other than the lateral obstacle, approach to the lateral obstacle is restricted from the start of the vehicle's parking assist or exit assist until the specified conditions are met.

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