JP2007237966A - Vehicular traveling control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicular traveling control device capable of preventing a sense of incongruity from being given to an occupant of an own vehicle when decelerating the own vehicle in speed by control when controlling an acceleration/deceleration means of the own vehicle so that a vehicle-to-vehicle distance detected by a vehicle-to-vehicle distance detection means maintains a target value. <P>SOLUTION: The target acceleration/deceleration speed Act is set based on the vehicle-to-vehicle distance detected by the vehicle-to-vehicle distance detection means and the target value (Step S8). When the set target acceleration/deceleration speed Act is deceleration, a correction coefficient J is set according to the vehicle-to-vehicle distance detected by the vehicle-to-vehicle distance detection means, and the target control value of the acceleration/deceleration means is set based on the value of the target acceleration/deceleration speed Act multiplied by its correction coefficient J (Steps S9-S11). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention controls acceleration / deceleration means for accelerating or decelerating the host vehicle so as to set a target inter-vehicle distance between the host vehicle and a preceding vehicle ahead thereof and to maintain the set target inter-vehicle distance. The present invention belongs to a technical field related to the vehicle travel control device.

  Conventionally, the inter-vehicle distance between the host vehicle and the preceding vehicle ahead thereof is detected by inter-vehicle distance detection means such as a radar, and the throttle valve is opened so that the detected inter-vehicle distance becomes a preset target inter-vehicle distance. 2. Description of the Related Art A travel control device that controls an acceleration / deceleration unit such as a degree and a brake to follow a host vehicle with respect to a preceding vehicle is well known (see, for example, Patent Document 1).

In such a travel control device, the target acceleration / deceleration of the host vehicle is normally set based on the difference between the inter-vehicle distance detected by the inter-vehicle distance detection means and the target inter-vehicle distance, and the set target acceleration / deceleration is set. Based on the speed, the control target value of the acceleration / deceleration means is set. That is, control target values such as the throttle valve opening and brake hydraulic pressure are set so that the host vehicle is accelerated or decelerated at the target acceleration / deceleration, and the acceleration / deceleration means is controlled so as to reach this control target value. . In this travel control device, the target acceleration / deceleration increases as the difference between the inter-vehicle distance between the preceding vehicle and the host vehicle and the target inter-vehicle distance increases. That is, the deceleration increases as the inter-vehicle distance becomes shorter than the target inter-vehicle distance, and the acceleration increases as the inter-vehicle distance becomes longer than the target inter-vehicle distance.
JP-A-8-192663

  However, in the conventional travel control device, the target acceleration / deceleration increases as the difference between the inter-vehicle distance and the target inter-vehicle distance increases regardless of the inter-vehicle distance between the preceding vehicle and the host vehicle. On the other hand, a problem occurs when the vehicle is shortened and the host vehicle is decelerated. In other words, if the difference between the inter-vehicle distance and the target inter-vehicle distance is the same, even if the inter-vehicle distance is quite long, the host vehicle will be decelerated at the same deceleration as when it is short. As a result, the occupant of the host vehicle feels uncomfortable because the vehicle decelerates at the same deceleration as when the distance is short although the distance feels that there is a margin as the inter-vehicle distance.

  The present invention has been made in view of such a point, and the object of the present invention is to maintain the target inter-vehicle distance so that the inter-vehicle distance detected by the inter-vehicle distance detection means is maintained as described above. When controlling the acceleration / deceleration means, when the host vehicle is decelerated by this control, an appropriate deceleration is performed according to the inter-vehicle distance between the preceding vehicle and the host vehicle to give a sense of incongruity to the passenger of the host vehicle. There is to be no.

  In order to achieve the above object, in the present invention, when the target acceleration / deceleration set based on the difference between the inter-vehicle distance detected by the inter-vehicle distance detection unit and the target inter-vehicle distance is a deceleration, the inter-vehicle distance detection unit The correction coefficient is set according to the inter-vehicle distance detected by the above, and the control target value of the acceleration / deceleration means is set based on a value obtained by multiplying the target acceleration / deceleration by the correction coefficient.

  Specifically, in the first aspect of the invention, the preceding vehicle recognition means for recognizing the preceding vehicle ahead of the own vehicle, and the inter-vehicle distance detection for detecting the inter-vehicle distance between the preceding vehicle recognized by the preceding vehicle recognition means and the own vehicle. Means, a target inter-vehicle distance setting means for setting a target inter-vehicle distance between the preceding vehicle and the own vehicle, an acceleration / deceleration means for accelerating or decelerating the own vehicle, and an inter-vehicle distance detected by the inter-vehicle distance detecting means. Further, the present invention is directed to a vehicle travel control device including travel control means for controlling the acceleration / deceleration means so as to maintain the target inter-vehicle distance set by the target inter-vehicle distance setting means.

  The travel control means sets the target acceleration / deceleration of the host vehicle based on the difference between the inter-vehicle distance detected by the inter-vehicle distance detection means and the target inter-vehicle distance set by the target inter-vehicle distance setting means. An acceleration / deceleration setting means; and a control target value setting means for setting a control target value of the acceleration / deceleration means by the travel control means based on the target acceleration / deceleration set by the target acceleration / deceleration setting means, When the target acceleration / deceleration set by the target acceleration / deceleration setting means is a deceleration, the control target value is provided with a correction coefficient setting means for setting a correction coefficient according to the inter-vehicle distance detected by the inter-vehicle distance detection means. The setting means is set to the target acceleration / deceleration by the correction coefficient setting means when the target acceleration / deceleration set by the target acceleration / deceleration setting means is deceleration. It is assumed to be configured to set the control target value based on the value obtained by multiplying the correction coefficient.

  With the above configuration, when the target acceleration / deceleration is set by the target acceleration / deceleration setting means and this target acceleration / deceleration is the deceleration (usually, when the inter-vehicle distance detected by the inter-vehicle distance detection means is smaller than the target inter-vehicle distance) The correction coefficient setting means sets a correction coefficient according to the inter-vehicle distance detected by the inter-vehicle distance detection means, and the control target value setting means sets the correction coefficient to the target acceleration / deceleration (that is, the target deceleration). A control target value for the acceleration / deceleration means is set based on the multiplied value. Since the correction coefficient is set according to the inter-vehicle distance detected by the inter-vehicle distance detection means, the host vehicle can be decelerated at an appropriate deceleration according to the inter-vehicle distance. That is, when the inter-vehicle distance is long, if the correction coefficient is set smaller than that when the inter-vehicle distance is short, the deceleration when the inter-vehicle distance is long can be performed more slowly than the deceleration when the inter-vehicle distance is short. it can. Therefore, when the inter-vehicle distance is long, the host vehicle is not decelerated at the same deceleration as when the distance is short, and the passengers of the host vehicle are not discomforted. On the other hand, when the inter-vehicle distance is short, the vehicle can be decelerated at a large deceleration by increasing the correction coefficient relatively, which gives a sense of security to the passengers of the vehicle and improves safety. be able to.

  In the invention of claim 2, in the invention of claim 1, the correction coefficient setting means is configured to set the correction coefficient to a smaller value as the inter-vehicle distance detected by the inter-vehicle distance detection means becomes longer. It shall be.

  Thus, as described above, when the inter-vehicle distance is long, the host vehicle can be slowly decelerated, whereas when the inter-vehicle distance is short, the host vehicle can be decelerated rapidly. As a result, it is possible to reliably perform appropriate deceleration according to the inter-vehicle distance, and to prevent the passengers of the own vehicle from feeling uncomfortable when the own vehicle is decelerated by the control of the acceleration / deceleration means. At the same time, it can give a sense of security.

  In the invention of claim 3, in the invention of claim 1 or 2, the occupant of the host vehicle selects one of the three options of long distance, medium distance and short distance as the target inter-vehicle distance. The target inter-vehicle distance setting means is configured to set the target inter-vehicle distance corresponding to the option selected by the operation switch, and the correction coefficient setting means is selected by the operation switch. It is assumed that the correction coefficient is set corresponding to the selected option.

  This makes it possible to decelerate the host vehicle at such a deceleration that does not give a sense of incongruity to the occupant of the host vehicle, regardless of the distance selected by the passenger of the host vehicle.

  As described above, according to the vehicle travel control device of the present invention, when the target acceleration / deceleration set based on the difference between the inter-vehicle distance detected by the inter-vehicle distance detection means and the target inter-vehicle distance is a deceleration, By setting the control target value of the acceleration / deceleration means based on the value obtained by multiplying the target acceleration / deceleration by the correction coefficient set according to the detected inter-vehicle distance, the preceding vehicle and the host vehicle The host vehicle can be decelerated at an appropriate deceleration according to the distance between the two vehicles, and when the host vehicle is decelerated by the control of the acceleration / deceleration means, the occupant of the host vehicle is not discomforted. It can give you a sense of security.

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

  FIG. 1 shows a vehicle W (corresponding to the host vehicle) equipped with a travel control apparatus according to an embodiment of the present invention. In the front portion of the driver's seat in the instrument panel 31 provided at the front end of the vehicle W. A meter unit 1 is provided. A steering wheel 32 is provided on the rear side (driver's seat side) of the meter unit 1, and the steering wheel 32 is provided with an operation unit 3 operated by an occupant.

  Further, the vehicle W includes a millimeter wave radar 5 that recognizes a preceding vehicle ahead of the vehicle W and detects an inter-vehicle distance between the recognized preceding vehicle and the vehicle W, and an autonomous vehicle that detects the vehicle speed of the vehicle W. A vehicle speed sensor 6 as a vehicle vehicle speed detection means, a brake sensor 8 for detecting that an occupant (driver) of the vehicle W depresses a brake pedal, a throttle or a brake for accelerating or decelerating the vehicle W, and the like. An auto actuator 9 is provided. The millimeter wave radar 5 can also detect the relative speed between the preceding vehicle and the vehicle W. From the relative speed and the vehicle speed of the vehicle W detected by the vehicle speed sensor 6, the millimeter wave radar 5 The vehicle speed will be detected. Thus, the millimeter wave radar 5 constitutes preceding vehicle recognition means for recognizing a preceding vehicle ahead of the own vehicle, and inter-vehicle distance detection means for detecting the inter-vehicle distance between the recognized preceding vehicle and the own vehicle. The wave radar 5 and the vehicle speed sensor 6 constitute a preceding vehicle vehicle speed detecting means for detecting the vehicle speed of the preceding vehicle.

  As shown in FIG. 2, the meter unit 1 is provided with instruments such as a speedometer 11 indicating the vehicle speed of the vehicle W detected by the vehicle speed sensor 6 and a tachometer 12 indicating the engine speed, A control state display unit 13 for displaying the state of control by the traveling control device is provided in the upper center portion of the meter unit 1.

  As shown in FIG. 3, the operation unit 3 is provided on a spoke portion 32 a on the right side of the vehicle among the three spoke portions 32 a on the left and right sides of the vehicle and below the center portion of the steering wheel 32. It consists of four operation switches that are lined up, down, left and right. In other words, the main switch 3a that activates or deactivates the traveling control device is provided in the upper left part of the operation unit 3, and the control by the traveling control device is canceled on the right side of the main switch 3a. A cancel switch 3b is provided, and under this cancel switch 3b, the occupant of the vehicle W has three options of a long distance, a medium distance, and a short distance as a target inter-vehicle distance between the vehicle W and the preceding vehicle. A target inter-vehicle distance selection switch 3c is provided as an operation switch for selecting one of the two, and the target vehicle speed of the vehicle W is set on the left side of the target inter-vehicle distance selection switch 3c and below the main switch 3a. A target vehicle speed setting switch 3d for setting is provided.

  Each time the target inter-vehicle distance selection switch 3c is operated (pressed) once, the target inter-vehicle distance selection switch 3c changes cyclically in the order of long distance, medium distance, and short distance. It is possible to select one option.

  The target vehicle speed setting switch 3d is operated by tilting a lever that protrudes toward the occupant to the upper side (the side described as “RES / +”) or the lower side (the side described as “SET / −”). Is supposed to do. Then, after the travel control device is activated by the main switch 3a, when the occupant first performs an operation of tilting the lever of the target vehicle speed setting switch 3d downward, the constant speed travel mode (auto cruise mode) And the vehicle speed detected by the vehicle speed sensor 6 at the time of the operation is set as the target vehicle speed. After this setting, if the operation of tilting the lever of the target vehicle speed setting switch 3d upward (operation in which the switch ON duration (operation duration) is within a predetermined time) is performed once, the target vehicle speed is increased by a predetermined speed. When the operation of tilting downward (operation in which the switch ON duration is within a predetermined time) is performed once, the target vehicle speed is decreased by a predetermined speed. Thereafter, once again, an operation of tilting the lever of the target vehicle speed setting switch 3d upward or downward (operation within a predetermined time) is performed once, the target vehicle speed is increased or decreased by a predetermined speed.

  In addition, when the operation of tilting the lever of the target vehicle speed setting switch 3d upward or downward is continued so as to exceed a predetermined time (when the switch ON is continued for a long time exceeding the predetermined time). Is updated by changing the target vehicle speed at a constant rate (for example, a rate of 2 km / h per second) from when the predetermined time is exceeded until the operation is completed.

  Further, after the travel control device is activated by the main switch 3a, when the operation of first tilting the lever of the target vehicle speed setting switch 3d is performed, the same operation as when performing the operation of tilting downward is performed. The constant speed running mode is set. At this time, the vehicle speed set by the occupant last time is set as the target vehicle speed.

  That is, in the present embodiment, the target vehicle speed setting switch 3d is used not only as a switch for setting the target vehicle speed of the vehicle W but also as a set switch 3e for changing the mode to the constant speed running mode and the resume switch 3f. is doing.

  When a preceding vehicle is present in front of the vehicle W, the constant speed traveling mode cannot be set, and the following traveling mode that follows the preceding vehicle is set as will be described later. That is, this traveling control device has an ACC (Adaptive Cruise Control) function.

  The control state display unit 13 is provided with various indicators as shown in detail in FIG. That is, a pre-crash indicator 14 for notifying the possibility of collision of the vehicle W with the preceding vehicle is provided at the upper left part of the control state display unit 13, and the traveling control device is provided below the pre-crash indicator 14. An operation state indicator 15 is provided which includes an “ON” display indicating that the vehicle is in an operating state and an “OFF” display indicating that the traveling control device is in an inoperative state. A brake indicator 16 is provided below the operation state indicator 15 to indicate that the brake is in an operation state when an occupant steps on the brake pedal.

  A standby state indicator 17 indicating that the present traveling control device is in a standby state is provided at the upper right portion of the control state display unit 13. Under this standby state indicator 17, the occupant selects the target inter-vehicle distance. An inter-vehicle distance selection indicator 18 for displaying the distance selected by the switch 3c (one of long distance (LONG), medium distance (MIDDLE), and short distance (SHORT)) is provided.

  An inter-vehicle distance indicator 19 (19a to 19c) in the form of a white line that is lit and displayed in accordance with the distance selected by the occupant by the target inter-vehicle distance selection switch 3c is provided on the upper part of the central portion in the left-right direction of the control state display unit 13. Three are provided on each side. When the distance selected by the target inter-vehicle distance selection switch 3c is a long distance, all the inter-vehicle distance indicators 19a to 19c are lit, and when the distance is a medium distance, the inter-vehicle distance indicators 19b and 19c are lit. When the distance is short, only the inter-vehicle distance indicator 19c is lit.

  Three preceding vehicle indicators 20 (20a to 20c) indicating a preceding vehicle located in front of the vehicle W are provided in a portion sandwiched between the left and right inter-vehicle distance indicators 19. If the inter-vehicle distance between the preceding vehicle and the vehicle W detected by the millimeter wave radar 5 is within a preset distance range corresponding to the far distance, the preceding vehicle indicator 20a is lit, If the vehicle is within the distance corresponding to the distance, the preceding vehicle indicator 20b is turned on. If the vehicle is within the distance corresponding to the short distance, the preceding vehicle indicator 20c is turned on.

  Below the inter-vehicle distance indicator 19 and the preceding vehicle indicator 20 in the control state display unit 13, a set vehicle speed indicator 21 for displaying the target vehicle speed set by the occupant with the target vehicle speed setting switch 3d is provided.

  As shown in FIG. 5, the travel control device includes a control unit 40, and the main switch 3 a, cancel switch 3 b, target inter-vehicle distance selection switch 3 c, and target vehicle speed setting in the operation unit 3 are compared with the control unit 40. Signals from the switch 3d, the set switch 3e, the resume switch 3f, the millimeter wave radar 5, the vehicle speed sensor 6, and the brake sensor 8 are input.

  Based on the input signal, the control unit 40 controls the auto actuator 9 by outputting a control signal for accelerating or decelerating, and controls the indicators 14 to 21 of the control state display unit 13 respectively. Control is performed by outputting necessary control signals.

  Specifically, when an ON operation signal is input from the main switch 3a, the control unit 40 activates the travel control device and causes the operation state indicator 15 to display “ON”. On the other hand, when an OFF operation signal is input from the main switch 3a, the traveling control device is deactivated, and the operation state indicator 15 is displayed as “OFF”.

  The control unit 40 also causes the operation state indicator 15 to display “OFF” even when an operation signal is input from the cancel switch 3b after the traveling control device is in the operation state.

  Further, when an operation signal is input from the inter-vehicle distance selection switch 3c, the control unit 40 outputs a control signal to the inter-vehicle distance selection indicator 18 and the inter-vehicle distance indicator 19 to operate the inter-vehicle distance selection switch 3c. A corresponding signal is displayed and a control signal is output to the auto actuator 9 so that the inter-vehicle distance detected by the millimeter wave radar 5 maintains a target inter-vehicle distance set as described later. Follow the preceding vehicle (following running mode). Therefore, the control unit 40 constitutes a travel control unit that controls the auto actuator 9 as the acceleration / deceleration unit so that the inter-vehicle distance maintains the target inter-vehicle distance. In the following traveling mode, a control signal is output to any one of the preceding vehicle indicators 20a to 20b according to the inter-vehicle distance detected by the millimeter wave radar 5.

  Further, when an operation signal is input from the target vehicle speed setting switch 3d, the set switch 3e, and the resume switch 3f, the control unit 40 outputs a control signal to the set vehicle speed indicator 21, and the target vehicle speed setting switch 3d The set vehicle speed and the like are displayed and a control signal is output to the auto actuator 9 so that the vehicle speed detected by the vehicle speed sensor 6 maintains the displayed vehicle speed (constant speed running mode). .

  Furthermore, when the signal from the brake sensor 8 is input, the control unit 40 turns on the brake indicator 16 and there is a possibility that the vehicle W may collide with the preceding vehicle depending on the inter-vehicle distance detected by the millimeter wave radar 5. If it is determined, the pre-crash indicator 14 is turned on.

  The control unit 40 stores preset first and second inter-vehicle times t1 and t2. The first and second inter-vehicle times t1 and t2 are set corresponding to the three options of the long distance, the medium distance, and the short distance, respectively. Specifically, the first inter-vehicle time t1 corresponding to the long distance is set to 2 s or more, the first inter-vehicle time t1 corresponding to the medium distance is set to 1.8 s, and the first inter-vehicle time t1 corresponding to the short distance is set to The inter-vehicle time t1 is set to 1.5 s or less, and the first inter-vehicle time t1 is set to be shorter in the order of long distance, medium distance, and short distance.

  On the other hand, the second inter-vehicle time t2 is set shorter than the first inter-vehicle time t2 corresponding to the same option. Specifically, the second inter-vehicle time t2 corresponding to a long distance is set to 1.8 s, the second inter-vehicle time t2 corresponding to a medium distance is set to 1.5 s, and a second corresponding to a short distance is set. The inter-vehicle time t2 is set to 1.2 s. Similarly to the first inter-vehicle time t1, the second inter-vehicle time t2 is set shorter in the order of long distance, medium distance, and short distance. This second inter-vehicle time t2 is preferably set to 0.7 times or more of the first inter-vehicle time t1 corresponding to the same option.

  The inter-vehicle time refers to the time from when the preceding vehicle stops to the time when the vehicle W reaches the preceding vehicle at the current speed.

  In the follow-up running mode, the control unit 40 determines the vehicle speed of the preceding vehicle (obtained from the relative speed detected by the millimeter wave radar 5 and the vehicle speed of the vehicle W detected by the vehicle speed sensor 6), and the occupant selects the target inter-vehicle distance. The first target inter-vehicle distance candidate is set based on the first inter-vehicle time t1 corresponding to the option selected by the switch 3c, and the own vehicle speed detected by the vehicle speed sensor 6 and the first option corresponding to the selected option are selected. The second target inter-vehicle distance candidate is set based on the second inter-vehicle time t2, and the longer one of the first and second target inter-vehicle distance candidates is set as the target inter-vehicle distance. Therefore, the control unit 40 constitutes a target inter-vehicle distance setting means in addition to the travel control means. The target inter-vehicle distance setting means is an option (long distance) selected by the occupant by the target inter-vehicle distance selection switch 3c. The target inter-vehicle distance is set corresponding to the intermediate distance or the short distance.

  The control unit 40 functions as target acceleration / deceleration setting means for setting the target acceleration / deceleration of the vehicle W based on the difference between the inter-vehicle distance detected by the millimeter wave radar 5 and the set target inter-vehicle distance. In the present embodiment, in addition to the difference between the detected inter-vehicle distance and the target inter-vehicle distance, the relative speed between the preceding vehicle and the vehicle W is also considered. Specifically, the value obtained by subtracting the target inter-vehicle distance from the inter-vehicle distance detected by the millimeter wave radar 5 (hereinafter referred to as target inter-vehicle deviation) and the relative speed (the direction in which the vehicle W is separated from the preceding vehicle) are corrected. The target acceleration / deceleration of the vehicle W is set based on the target acceleration / deceleration map (see FIG. 6) stored in the control unit 40. The numerical values (0, -0.1, 0.15, etc.) of the target acceleration / deceleration (Act) shown in the target acceleration / deceleration map of FIG. 6 are indexed so that the relative magnitude can be understood. A positive value indicates acceleration, and a negative value indicates deceleration. When the target acceleration / deceleration is acceleration (positive value), the larger the numerical value, the larger the target acceleration. When the target acceleration / deceleration is deceleration (negative value), the larger the absolute value, the larger the target The deceleration will be large.

  In the target acceleration / deceleration map, when the relative speed between the preceding vehicle and the vehicle W is 0, when the target inter-vehicle deviation is 0, the target acceleration / deceleration is 0 and the target inter-vehicle deviation is positive (millimeter wave). When the inter-vehicle distance detected by the radar 5 is larger than the target inter-vehicle distance), the target acceleration / deceleration (that is, the target acceleration) is increased as the target inter-vehicle deviation increases, and the target inter-vehicle deviation is negative (millimeter wave radar). When the inter-vehicle distance detected by 5 is smaller than the target inter-vehicle distance), the absolute value of the target acceleration / deceleration is increased (that is, the target deceleration is increased) as the absolute value of the target inter-vehicle deviation increases. Further, when the relative speed between the preceding vehicle and the vehicle W is positive, the target acceleration / deceleration is increased as compared with the case where it is 0, and when the relative speed is negative, it is compared with the case where it is 0. Decrease the target acceleration / deceleration (if the target acceleration / deceleration is a negative value, increase the absolute value).

  The control unit 40 serves as a control target value setting means for setting a control target value such as the throttle valve opening of the auto actuator 9 or the brake hydraulic pressure by the control unit 40 based on the set target acceleration / deceleration. Function. At this time, if the target acceleration / deceleration is a deceleration (negative value), the control unit 40 sets a correction coefficient according to the inter-vehicle distance detected by the millimeter wave radar 5, and the target acceleration / deceleration ( That is, the control target value is set based on a value obtained by multiplying the target deceleration) by the correction coefficient. Therefore, the control unit 40 also constitutes a correction coefficient setting unit. On the other hand, when the target acceleration / deceleration is acceleration (positive value) or 0, the control target value is set based on the set target acceleration / deceleration without multiplication by a correction coefficient. After setting the control target value, the control unit 40 outputs a control signal for setting the control target value to the auto actuator 9.

  In the present embodiment, the correction coefficient is set using a correction coefficient map (see FIG. 7) stored in the control unit 40. That is, the control unit 40 corrects from the correction coefficient map based on the inter-vehicle distance detected by the millimeter wave radar 5 and the option (long distance, medium distance or short distance) selected by the occupant using the target inter-vehicle distance selection switch 3c. Set the coefficient. Thus, the control unit 40 sets the correction coefficient corresponding to the option selected by the occupant using the target inter-vehicle distance selection switch 3c, and the smaller the inter-vehicle distance detected by the millimeter wave radar 5 in each option, the smaller the value. Will be set to. For this reason, when the control unit 40 decelerates the vehicle W, the longer the inter-vehicle distance detected by the millimeter wave radar 5, the smaller the deceleration of the vehicle W becomes. Further, the deceleration of the vehicle W decreases in the order of the long distance, medium distance, and short distance. In the correction coefficient map of FIG. 7, the correction coefficient is set to 1.0 or less. On the short side distance (especially in the case of a short distance), the correction coefficient is 1. A value larger than 0 may be used.

  Here, the processing operation in the follow-up running mode by the control unit 40 will be described with reference to the flowchart of FIG.

  First, in the first step S1, the speed (vehicle speed) of the vehicle W is input from the vehicle speed sensor 6, and the distance between the preceding vehicle and the vehicle W and the relative speed between the preceding vehicle and the vehicle W are determined from the millimeter wave radar 5. input.

  In the next step S2, the vehicle speed of the preceding vehicle is calculated from the input own vehicle speed and relative speed, and in the next step S3, a first target inter-vehicle distance candidate TgL1 is set. That is, the first target inter-vehicle distance candidate TgL1 is set by the product of the vehicle speed of the preceding vehicle, which is the calculation result of step S2, and the first inter-vehicle time t1 corresponding to the distance selected by the target inter-vehicle distance selection switch 3c. .

  In the next step S4, a second target inter-vehicle distance candidate TgL2 is set. That is, the first target inter-vehicle distance candidate TgL2 is set by the product of the host vehicle speed input in step S1 and the second inter-vehicle time t2 corresponding to the distance selected by the target inter-vehicle distance selection switch 3c.

  In the next step S5, it is determined whether or not the first target inter-vehicle distance candidate TgL1 is larger than the second target inter-vehicle distance candidate TgL2, and when the determination in step S5 is YES, the process proceeds to step S6. While the first target inter-vehicle distance candidate TgL1 is set to the target inter-vehicle distance TgL, when the determination in step S5 is NO, the process proceeds to step S7, and the second target inter-vehicle distance candidate TgL2 is set to the target inter-vehicle distance TgL. .

  In step S8 following step S6 and step S7, the target inter-vehicle deviation, which is a value obtained by subtracting the target inter-vehicle distance TgL from the inter-vehicle distance detected by the millimeter wave radar 5, and the relative speed between the preceding vehicle and the vehicle W are obtained. Based on the target acceleration / deceleration map, the target acceleration / deceleration Act is set.

  In the next step S9, it is determined whether or not the target acceleration / deceleration Act set in step S8 is smaller than 0 (that is, whether it is a deceleration). If the determination in step S9 is YES, Proceeding to S10, based on the distance (long distance, medium distance or short distance) selected by the occupant using the target inter-vehicle distance selection switch 3c and the inter-vehicle distance detected by the millimeter wave radar 5, the correction coefficient is calculated from the correction coefficient map. Set J. In the next step S11, the control target value of the auto actuator 9 is set based on the product value of the target acceleration / deceleration Act and the correction coefficient J, and then the process proceeds to step S13.

  On the other hand, when the determination in step S9 is NO, the process proceeds to step S12, the control target value of the auto actuator 9 is set based on the value of the target acceleration / deceleration Act, and then the process proceeds to step S13.

  In step S13, a control signal for setting the control target value set in step S11 or S12 is output to the auto actuator 9.

  By the processing operation of the control unit 40, the first target inter-vehicle distance candidate TgL1 based on the vehicle speed of the preceding vehicle and the first inter-vehicle time t1, and the second target inter-vehicle space based on the vehicle speed of the vehicle W and the second inter-vehicle time t2. The distance candidate TgL2 is set, and the longer one of these candidates is set as the target inter-vehicle distance TgL. As a result, when the vehicle W is traveling following the preceding vehicle that is traveling at a substantially constant speed, the vehicle speed of the vehicle W and the preceding vehicle is substantially the same, so the target inter-vehicle distance TgL is It becomes a target inter-vehicle distance candidate corresponding to the longer inter-vehicle time among the second inter-vehicle times t1, t2. In the present embodiment, since the first inter-vehicle time t1 is longer, the first target inter-vehicle distance candidate TgL1 is set as the target inter-vehicle distance TgL. For example, if the distance selected by the target inter-vehicle distance selection switch 3c is a medium distance and the preceding vehicle is traveling at 72 km / h, the target inter-vehicle distance TgL is 36 m (72000/3600 × 1.8). Become.

  Then, based on the target inter-vehicle deviation, which is a value obtained by subtracting the target inter-vehicle distance TgL from the inter-vehicle distance detected by the millimeter wave radar 5, and the relative speed between the preceding vehicle and the vehicle W, the target acceleration / deceleration map is used. When the acceleration / deceleration Act is set and the target acceleration / deceleration Act is a negative value, the correction coefficient J is set from the correction coefficient map, and the product value of the target acceleration / deceleration Act and the correction coefficient J is set. Based on this, the control target value of the auto actuator 9 is set. On the other hand, when the target acceleration / deceleration Act is not a negative value, the control target value of the auto actuator 9 is set based on the value of the target acceleration / deceleration Act.

  Here, consider a case where the preceding vehicle decelerates. If the preceding vehicle decelerates suddenly from 72 km / h to 36 km / h, for example, the first target inter-vehicle distance candidate TgL1 is larger until the preceding vehicle decelerates from 72 km / h to 60 km / h. When the vehicle speed becomes slower than 60 km / h, the second target inter-vehicle distance candidate TgL2 becomes larger (TgL1 = TgL2 = 30 m when the vehicle speed of the preceding vehicle is 60 km / h). When the vehicle speed of the preceding vehicle reaches 36 km / h, the first target inter-vehicle distance candidate TgL1 is 18 m, and the second target inter-vehicle distance candidate TgL2 is 30 m. Therefore, assuming that the target inter-vehicle distance TgL is set only by the first target inter-vehicle distance candidate TgL1 based on the vehicle speed of the preceding vehicle, if the preceding vehicle decelerates rapidly from 72 km / h to 36 km / h, for example, Although the distance TgL is 18 m, the actual inter-vehicle distance immediately after deceleration of the preceding vehicle is close to 36 m and longer than 18 m. As a result, the vehicle W is not decelerated suddenly. In this case, the occupant of the vehicle W is given a feeling that the vehicle W approaches the preceding vehicle rapidly.

  However, in the present embodiment, the longer one of the first target inter-vehicle distance candidate TgL1 and the second target inter-vehicle distance candidate TgL2 based on the vehicle speed of the vehicle W is set as the target inter-vehicle distance TgL. In this case, the target inter-vehicle distance TgL is 30 m, the vehicle W is appropriately decelerated, and the inter-vehicle distance between the preceding vehicle and the vehicle W is maintained at 30 m.

  Further, in the present embodiment, the detection is performed when the target acceleration / deceleration Act set based on the difference between the inter-vehicle distance detected by the millimeter wave radar 5 and the set target inter-vehicle distance TgL is a deceleration. The correction coefficient J is set according to the inter-vehicle distance, the correction coefficient J is set to a smaller value as the detected inter-vehicle distance is longer, and the target acceleration / deceleration Act is multiplied by the correction coefficient J. Since the control target value of the auto actuator 9 is set based on this, the longer the inter-vehicle distance between the preceding vehicle and the vehicle W, the smaller the deceleration of the vehicle W, and the longer the inter-vehicle distance between the preceding vehicle and the vehicle W. In such a case, the vehicle W slowly decelerates, whereas when the inter-vehicle distance is short, the vehicle W decelerates rapidly. As a result, when the inter-vehicle distance is long, the vehicle W will not be decelerated at the same deceleration as when the inter-vehicle distance is short, and the passengers of the vehicle W will not be discomforted. Conversely, the inter-vehicle distance is short. In this case, since the vehicle W decelerates with a large deceleration, it is possible to give the passengers of the vehicle W a sense of security and improve safety.

  In the above embodiment, the longer one of the first target inter-vehicle distance candidate based on the vehicle speed of the preceding vehicle and the second target inter-vehicle distance candidate based on the vehicle speed of the vehicle W is set as the target inter-vehicle distance. However, the first target inter-vehicle distance candidate based on the vehicle speed of the preceding vehicle may be set as the target inter-vehicle distance as it is. Further, it is not necessary to set the target inter-vehicle distance based on the preset inter-vehicle time, and any method for setting the target inter-vehicle distance may be used.

  In the above embodiment, the occupant of the vehicle W is provided with the target inter-vehicle distance selection switch 3c that selects one of the three options of the long distance, the medium distance, and the short distance as the target inter-vehicle distance. The target inter-vehicle distance selection switch 3c may be omitted. In this case, the first and second inter-vehicle time may be set one by one in advance, and the correction coefficient map only needs to correspond to, for example, a medium distance.

  The present invention controls acceleration / deceleration means for accelerating or decelerating the host vehicle so as to set a target inter-vehicle distance between the host vehicle and a preceding vehicle ahead thereof and to maintain the set target inter-vehicle distance. This is useful for the vehicle travel control apparatus.

It is a block diagram of the vehicle carrying the traveling control apparatus which concerns on embodiment of this invention. It is an enlarged view of the meter unit provided in the instrument panel of the said vehicle. It is a block diagram of the steering wheel of the said vehicle. It is an enlarged view which shows the detail of the control state display part in the meter unit of FIG. It is a block diagram which shows the structure of the said travel control apparatus. It is a figure which shows a target acceleration / deceleration map. It is a figure which shows a correction coefficient map. It is a flowchart which shows the processing operation at the time of follow-up driving mode in a control unit.

Explanation of symbols

W vehicle (own vehicle)
3c Target inter-vehicle distance selection switch (operation switch)
5 Millimeter wave radar (preceding vehicle recognition means) (vehicle distance detection means)
9 Auto actuator (acceleration / deceleration means)
40 control unit (target inter-vehicle distance setting means) (travel control means)
(Target acceleration / deceleration setting means) (Control target value setting means)
(Correction coefficient setting means)

Claims (3)

A preceding vehicle recognition means for recognizing a preceding vehicle ahead of the own vehicle, an inter-vehicle distance detection means for detecting an inter-vehicle distance between the preceding vehicle recognized by the preceding vehicle recognition means and the own vehicle, and a target of the preceding vehicle and the own vehicle The target inter-vehicle distance setting means for setting the inter-vehicle distance, the acceleration / deceleration means for accelerating or decelerating the host vehicle, and the inter-vehicle distance detected by the inter-vehicle distance detection means are set by the target inter-vehicle distance setting means. A travel control device for a vehicle comprising travel control means for controlling the acceleration / deceleration means so as to maintain an inter-vehicle distance,
The travel control means sets a target acceleration / deceleration for setting a target acceleration / deceleration of the host vehicle based on a difference between the inter-vehicle distance detected by the inter-vehicle distance detection means and the target inter-vehicle distance set by the target inter-vehicle distance setting means. Setting means, and control target value setting means for setting a control target value of the acceleration / deceleration means by the travel control means based on the target acceleration / deceleration set by the target acceleration / deceleration setting means,
When the target acceleration / deceleration set by the target acceleration / deceleration setting means is deceleration, a correction coefficient setting means is provided for setting a correction coefficient according to the inter-vehicle distance detected by the inter-vehicle distance detection means,
The control target value setting means is a value obtained by multiplying the target acceleration / deceleration by the correction coefficient set by the correction coefficient setting means when the target acceleration / deceleration set by the target acceleration / deceleration setting means is deceleration. A travel control device for a vehicle, wherein the control target value is set based on The vehicle travel control apparatus according to claim 1,
The vehicle travel control device, wherein the correction coefficient setting means is configured to set the correction coefficient to a smaller value as the inter-vehicle distance detected by the inter-vehicle distance detection means is longer. In the vehicle travel control device according to claim 1 or 2,
An occupant of the own vehicle has an operation switch for selecting one of three options of long distance, medium distance and short distance as the target inter-vehicle distance,
The target inter-vehicle distance setting means is configured to set the target inter-vehicle distance corresponding to the option selected by the operation switch,
The vehicle travel control device, wherein the correction coefficient setting means is configured to set the correction coefficient corresponding to an option selected by the operation switch.

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