Vehicle and computer program

Abstract

To enable a vehicle behavior to be properly controlled during following travelling so that the vehicle behavior can achieve an effect which a vehicle user considers important.SOLUTION: A vehicle 100 is equipped with a control device 6 that controls a vehicle behavior, so that operation support or automatic operation is executed. When executing following travelling for making an own vehicle follow an object to be followed during the operation support or during the automatic operation, the control device 6 sets a travelling mode in which the vehicle travels following the object, on the basis of a target inter-vehicle distance at the time of the following travelling, and sets the mode to a travelling mode in which at least either of an upper limit side and a lower limit side of an allowable range for acceleration at the time of acceleration and deceleration is expanded more when a set value of the target inter-vehicle distance is small in comparison with when the set value is large.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle.

Background Art

[0002] Patent Document 1 discloses a vehicle control device that calculates a target inter-vehicle distance based on the vehicle speed in order to follow a preceding vehicle and performs acceleration / deceleration control of the host vehicle.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When performing a following driving to make the host vehicle follow a preceding vehicle, the air resistance of the host vehicle can be reduced. Therefore, the energy consumption (fuel consumption or power consumption) of the host vehicle can be reduced and the cruising range of the host vehicle can be increased.

[0005] The fuel efficiency improvement effect due to this air resistance reduction becomes lower as the inter-vehicle distance from the preceding vehicle increases. Therefore, it is desirable to make the inter-vehicle distance as small as possible during following driving. However, for this purpose, in order to prevent a collision with the preceding vehicle when the preceding vehicle decelerates, it is necessary to allow the vehicle user to accept a large deceleration. Also, when the preceding vehicle accelerates during following driving and the inter-vehicle distance from the preceding vehicle becomes larger than the target inter-vehicle distance, it is desirable to return the inter-vehicle distance to the target inter-vehicle distance as soon as possible. However, for this purpose, it is necessary to allow the vehicle user to accept a large acceleration.

[0006] Thus, in order to enhance the fuel efficiency improvement effect by reducing air resistance, it is necessary to enable at least one of acceleration with a large acceleration and deceleration with a large deceleration during following driving. However, if such acceleration and deceleration are allowed, the ride comfort of the vehicle will deteriorate. And among vehicle users, there are those who prioritize ride comfort even during following driving rather than the fuel efficiency improvement effect by reducing air resistance. Also, depending on the situation, there may be cases where one wants to prioritize ride comfort.

[0007] Therefore, it is necessary to appropriately control the vehicle behavior during following driving so as to achieve a vehicle behavior that can obtain the effects that vehicle users value.

[0008] The present invention has been made paying attention to such problems, and an object thereof is to enable appropriate control of the vehicle behavior during following driving so as to achieve a vehicle behavior that can obtain the effects that vehicle users value.

Means for Solving the Problems

[0009] In order to solve the above problems, a vehicle according to an aspect of the present invention includes a control device that controls vehicle behavior to perform driving support or autonomous driving. And when the control device performs following driving in which the host vehicle follows a following object during driving support or autonomous driving, it sets the driving mode during following driving based on the target inter-vehicle distance during following driving, and when the set value of the target inter-vehicle distance is small, compared with when it is large, it is configured to set a driving mode in which at least one of the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration is expanded.

Effects of the Invention

[0010] According to this aspect of the present invention, when the target inter-vehicle distance during following driving is small, that is, when the vehicle user values the fuel consumption improvement effect due to reduction of air resistance more than the ride comfort of the vehicle, a driving mode is set in which at least one of the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration is expanded. Therefore, it is possible to appropriately control the vehicle behavior during following driving so that the vehicle behavior that provides the effect valued by the vehicle user is achieved.

Brief Description of Drawings

[0011]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments will be described in detail with reference to the drawings. In the following description, the same reference numerals are assigned to the same components.

[0013] FIG. 1 is a schematic system configuration diagram of a vehicle 100 according to an embodiment of the present invention.

[0014] As shown in FIG. 1, the vehicle 100 according to the present embodiment includes a peripheral information acquisition device 1, a current position detection device 2, a human machine interface (hereinafter referred to as "HMI"), a communication device 4, a vehicle behavior detection device 5, and an electronic control unit 6. The peripheral information acquisition device 1, the current position detection device 2, the HMI 3, the communication device 4, and the vehicle behavior detection device 5 are electrically connected to the electronic control unit 6 via an in-vehicle network conforming to a standard such as CAN (Controller Area Network).

[0015] The peripheral information acquisition device 1 is a device for acquiring information on the surrounding environment of the host vehicle (hereinafter referred to as "vehicle peripheral information"). The vehicle peripheral information acquired by the peripheral information acquisition device 1 is transmitted to the electronic control unit 6 via the in-vehicle network. The peripheral information acquisition device 1 can be composed of a single device or a plurality of devices, and can be composed of, for example, a camera, a LiDAR (Light Detection and Ranging), a millimeter-wave radar sensor, an ultrasonic sensor, etc.

[0016] In the present embodiment, as the peripheral information acquisition device 1, a camera 11 that captures the surroundings of the host vehicle, a LiDAR 12 that detects an object including other vehicles around the host vehicle using laser light, and a millimeter-wave radar sensor 13 that detects an object around the host vehicle over a longer distance than the LiDAR 12 using radio waves are provided.

[0017] The current position detection device 2 is a device for detecting the current position of the host vehicle (for example, the longitude and latitude of the vehicle). Examples of the current position detection device 2 include, but are not limited to, a GNSS receiver that detects the current position based on each satellite radio wave received from a plurality of satellites. The vehicle current position detected by the current position detection device 2 is transmitted to the electronic control unit 6 via the in-vehicle network.

[0018] The HMI 3 is an interface for inputting and outputting information between the vehicle 100 and its user (for example, a driver, a passenger, an external operator of the vehicle, etc.). The HMI 3 includes an output device for outputting information provided to the vehicle user and an input device for the vehicle user to perform various input operations. Examples of the output device include a display, a speaker, a vibration unit, etc. Examples of the input device include a touch panel, an operation button, an operation switch, a microphone, etc. The HMI 3 provides the output information received from the electronic control unit 6 via the in-vehicle network to the vehicle user via the output device. Further, the HMI 3 transmits the input information input via the input device to the electronic control unit 6 via the in-vehicle network.

[0019] Incidentally, the HMI 3 can be pre-mounted on the vehicle 100 in advance, or a terminal (for example, a smartphone, a tablet, a personal computer, etc.) owned by the vehicle user can be connected to the electronic control unit 6 by wire or wirelessly to make the terminal function as the HMI 3.

[0020] In the present embodiment, the electronic control unit 6 can automatically or manually by the vehicle user via the HMI 3 set the driving mode of the vehicle 100 to an arbitrary driving mode so that the vehicle behavior during vehicle travel can be changed. Specifically, in the present embodiment, as the driving mode of the vehicle 100, an arbitrary driving mode can be selected from at least two driving modes, i.e., a first driving mode and a second driving mode.

[0021] The first driving mode is, for example, a driving mode that prioritizes comfort such as riding comfort, and is a driving mode in which the allowable range of acceleration during acceleration and deceleration is limited to a relatively narrow range. The upper limit value (positive value) of the allowable range is the upper limit value of the acceleration allowed during acceleration. The lower limit value (negative value) of the allowable range is the lower limit value of the acceleration allowed during deceleration, or in other words, the upper limit value of the deceleration allowed during deceleration.

[0022] By limiting the allowable range of acceleration during acceleration and deceleration to a narrow range in this way, large acceleration during acceleration and large deceleration during deceleration are not performed during driving assistance or automatic driving, so that it is possible to suppress the deterioration of the riding comfort of the vehicle.

[0023] The second driving mode is, for example, a driving mode that prioritizes acceleration performance, etc., and is a driving mode in which the allowable range of acceleration during acceleration and deceleration is larger than that of the first driving mode.

[0024] By setting the driving mode to the second driving mode, when the host vehicle is following a preceding vehicle during driving assistance or autonomous driving, even if the preceding vehicle accelerates and the inter-vehicle distance from the preceding vehicle temporarily becomes larger than the target inter-vehicle distance, a large acceleration can be performed to quickly return the inter-vehicle distance to the target inter-vehicle distance. Also, when the preceding vehicle decelerates, a large deceleration can be performed, so the value of the target inter-vehicle distance can be set to a smaller value compared to the first driving mode.

[0025] The communication device 4 is a device for communicating with the outside of the vehicle. The communication device 4 includes a wide-area communication device for communicating with the outside of the vehicle via a wireless communication network, and a narrow-area communication device for directly communicating between terminals (for example, between vehicles, between a road and a vehicle, between a pedestrian and a vehicle).

[0026] The vehicle behavior detection device 5 detects parameters indicating the behavior of the vehicle 100 (hereinafter referred to as "vehicle behavior information"). The vehicle behavior information detected by the vehicle behavior detection device 5 is transmitted to the electronic control unit 6 via the in-vehicle network. Examples of the vehicle behavior detection device 5 include a vehicle speed sensor, an acceleration sensor, a steering angle sensor, etc. Examples of the vehicle behavior information include the vehicle speed, acceleration, steering angle, etc. detected by these sensors.

[0027] The electronic control unit 6 includes a communication interface (communication I / F) 61, a memory 62, and a processor 63.

[0028] The communication interface 61 includes an interface circuit for connecting the electronic control unit 6 to the in-vehicle network. The electronic control unit 6 is connected to various in-vehicle devices such as the above-mentioned peripheral information acquisition device 1 via this communication interface 61.

[0029] The memory 62 has a storage medium such as an HDD (Hard Disk Drive), an optical recording medium, or a semiconductor memory. The memory 62 stores various computer programs and data executed in the processor 63. The memory 62 also stores data generated by a computer program and data received from various in-vehicle devices via the communication interface 61.

[0030] The processor 63 includes one or more CPUs (Central Processing Unit) and its peripheral circuits. The processor 63 executes various processes based on various computer programs stored in the memory 62.

[0031] For example, during driving assistance or autonomous driving, the processor 63 creates a driving plan for the host vehicle based on vehicle surrounding information, vehicle behavior information, etc., and automatically performs driving operations related to acceleration, steering, and braking according to the driving plan, thereby implementing a following driving in which the host vehicle follows the preceding vehicle. Examples of following driving include Adaptive Cruise Control (ACC) in which driving operations related to acceleration and braking are automatically performed so that the distance between the host vehicle and the preceding vehicle is kept constant, and platooning in which driving operations related to acceleration, steering, and braking are automatically performed so that the host vehicle can change lanes in accordance with the lane change of the preceding vehicle while keeping the distance between the host vehicle and the preceding vehicle constant, and the host vehicle can follow the preceding vehicle while tracing the position within the lane of the preceding vehicle.

[0032] As described above, by performing following driving, the air resistance of the host vehicle can be reduced. As a result, the energy consumption (fuel consumption or power consumption) of the host vehicle can be reduced, and the cruising range of the host vehicle can be increased. In particular, by following the preceding vehicle while tracing the position within the lane of the preceding vehicle (that is, by also performing left-right vehicle behavior control within the lane to follow the preceding vehicle), the air resistance of the host vehicle can be reduced more effectively. And the fuel efficiency improvement effect due to this air resistance reduction tends to be higher when the inter-vehicle distance from the preceding vehicle is small than when it is large.

[0033] Therefore, during following driving, it is desirable to set the target inter-vehicle distance from the preceding vehicle to as small a value as possible. However, for that purpose, in order to prevent collision with the preceding vehicle when the preceding vehicle decelerates, it is necessary to allow the vehicle user to tolerate a large deceleration. Also, when the preceding vehicle accelerates during following driving and the inter-vehicle distance from the preceding vehicle becomes larger than the target inter-vehicle distance, it is desirable to return the inter-vehicle distance to the target inter-vehicle distance as soon as possible. However, for that purpose, it is necessary to allow the vehicle user to tolerate a large acceleration.

[0034] Thus, in order to enhance the fuel efficiency improvement effect due to air resistance reduction, it is necessary to enable at least one of large acceleration and large deceleration during following driving. However, allowing such acceleration and deceleration will deteriorate the ride comfort of the vehicle 100. And it is considered that among vehicle users, there are those who prioritize ride comfort over the fuel efficiency improvement effect due to air resistance reduction even during following driving. Also, it is considered that even vehicle users who usually prioritize the fuel efficiency improvement effect due to air resistance reduction may want to prioritize ride comfort depending on the situation.

[0035] Therefore, it is necessary to appropriately control the vehicle behavior during following driving so that the vehicle behavior that can obtain the effect that the vehicle user values is achieved.

[0036] When the set value of the target inter-vehicle distance during following driving is small, it is considered that the vehicle user values the fuel efficiency improvement effect due to reduced air resistance rather than the ride comfort. On the other hand, when the vehicle user increases the set value of the target inter-vehicle distance during following driving, it is considered that the user hopes to perform following driving that does not require sudden acceleration or deceleration, that is, following driving that emphasizes ride comfort.

[0037] Therefore, in the present embodiment, the driving mode during following driving is set based on the target inter-vehicle distance during following driving. Hereinafter, with reference to FIG. 2, the content of the driving mode setting process according to the present embodiment, which is executed by the processor 63 and thus the electronic control unit 6, will be described. The electronic control unit 6 repeatedly executes this process at a predetermined calculation cycle during vehicle driving.

[0038] In step S101, the electronic control unit 6 determines whether following driving is being performed during driving assistance or autonomous driving. If the electronic control unit 6 is performing following driving, it proceeds to the process of step S102. On the other hand, if the electronic control unit 6 is not performing following driving, it ends the current process.

[0039] In step S102, the electronic control unit 6 determines whether the set value of the target inter-vehicle distance is less than or equal to a predetermined value. In the present embodiment, the predetermined value is the shortest distance among the inter-vehicle distances that can be set as the target inter-vehicle distance. The set value of the target inter-vehicle distance can be changed by the user of the own vehicle via the HMI 3. If the set value of the target inter-vehicle distance is less than or equal to the predetermined value, the electronic control unit 6 proceeds to the process of step S103. On the other hand, if the set value of the target inter-vehicle distance is greater than the predetermined value, the electronic control unit 6 proceeds to the process of step S104.

[0040] In step S103, the electronic control unit 6 sets the driving mode to the second driving mode.

[0041] In step S104, the electronic control unit 6 sets the driving mode to the first driving mode.

[0042] The vehicle 100 according to the embodiment described above includes an electronic control unit 6 (control device) that controls vehicle behavior to perform driving support or automatic driving. When the electronic control unit 6 performs a following driving operation to make the host vehicle follow a preceding vehicle (following object) during driving support or automatic driving, it sets the driving mode during following driving based on the target inter-vehicle distance during following driving. When the set value of the target inter-vehicle distance is small, at least one of the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration is set to be expanded compared to when it is large, and it is configured to set the driving mode.

[0043] Specifically, the vehicle according to the present embodiment has, as driving modes, a first driving mode and a second driving mode in which both the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration are expanded compared to the first driving mode. The electronic control unit 6 (control device) is configured to set the driving mode to the second driving mode when the set value of the target inter-vehicle distance is equal to or less than a predetermined value.

[0044] Thereby, when the set value of the target inter-vehicle distance during following driving is small, that is, when it is considered that the vehicle user values the fuel efficiency improvement effect by reducing air resistance rather than the ride comfort of the vehicle, the driving mode of the vehicle is set to a driving mode in which the allowable range of acceleration during acceleration and deceleration is relatively wide. When the set value of the target inter-vehicle distance during following driving is large, that is, when it is considered that the vehicle user values the ride comfort of the vehicle, the driving mode of the vehicle can be set to a driving mode in which the allowable range of acceleration during acceleration and deceleration is relatively narrow. Therefore, it is possible to appropriately control the vehicle behavior during following driving so that the vehicle behavior that obtains the effect that the vehicle user values is achieved.

[0045] Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

[0046] For example, in the above embodiment, the computer program executed in the electronic control unit 6 may be provided in a form recorded on a computer-readable portable recording medium such as a semiconductor memory, a magnetic recording medium, or an optical recording medium.

[0047] Also, in the above embodiment, both the upper and lower limits of the allowable range of acceleration during acceleration and deceleration in the second driving mode are expanded compared to the first mode, but at least one of the upper and lower limits of the allowable range may be expanded compared to the first mode.

[0048] 3 HMI (Information Input Device) 6 Electronic Control Unit (Control Device) 100 Vehicle

Claims

1. A vehicle comprising a control device that controls vehicle behavior to perform driving assistance or autonomous driving, wherein the control device, when performing a following driving operation to make the host vehicle follow a following object during driving assistance or autonomous driving, sets the driving mode during the following driving operation based on the target inter-vehicle distance during the following driving operation, when the set value of the target inter-vehicle distance is small, compared with when it is large, sets the driving mode to a driving mode in which at least one of the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration is expanded, has, as the driving mode, a first driving mode and a second driving mode in which both the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration are expanded compared with the first driving mode, and is configured to set the driving mode to the second driving mode when the set value of the target inter-vehicle distance is equal to or less than a predetermined value, a vehicle.

2. The predetermined value is the shortest distance among the inter-vehicle distances that can be set as the target inter-vehicle distance, The vehicle according to claim 1.

3. When performing a following driving operation to make the host vehicle follow a following object during driving assistance or autonomous driving, set the driving mode during the following driving operation based on the target inter-vehicle distance during the following driving operation, when the set value of the target inter-vehicle distance is small, compared with when it is large, set the driving mode to a driving mode in which at least one of the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration is expanded, has, as the driving mode, a first driving mode and a second driving mode in which both the upper limit side and the lower limit side of the allowable range of acceleration during acceleration and deceleration are expanded compared with the first driving mode, and when the set value of the target inter-vehicle distance is equal to or less than a predetermined value, causes a computer to execute a process of setting the driving mode to the second driving mode.

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