JP2005289142A - Follow-up traveling control method, and follow-up traveling control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve follow-up travel performance by preventing waste acceleration/deceleration when one's own vehicle starts following a preceding vehicle. <P>SOLUTION: The follow-up traveling control device has a control function of a radar follow-up mode of controlling the acceleration/deceleration of the own vehicle 1 based on the difference between the own vehicle speed and the command vehicle speed on the radar detection mode side by detecting the inter-vehicle distance between the own vehicle 1 and the preceding vehicle and the relative speed of the preceding vehicle based on radar survey in front of the own vehicle. The follow-up traveling control device also has a control function of a driver set mode of calculating a predetermined delay characteristic based on the operated and set target vehicle speed, hence calculating a command vehicle speed on the driver set side reaching the target vehicle speed in the delay characteristic, and controlling the acceleration/deceleration of the own vehicle 1 based on the difference between the own vehicle speed and the command vehicle speed on the driver set side. The follow-up travel of the own vehicle by the control function of the driver set mode until the detected inter-vehicle distance shortens to a predetermined control switch distance or the shorter. When the detected inter-vehicle distance shortens to the predetermined control switch distance or the shorter, the control by the control function of the driver set mode is switched to the control by the control function of the radar follow-up mode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a follow-up running control method and a follow-up running control apparatus, and more particularly to control when catching up with a preceding vehicle such as when starting.

Conventionally, in vehicle tracking control, the distance between the vehicle and the preceding vehicle and the relative speed of the preceding vehicle are detected on the basis of radar surveys in front of the vehicle by laser radar, millimeter wave radar, etc. Based on the difference between the current vehicle speed and the commanded vehicle speed, acceleration / deceleration control is performed by controlling the vehicle's throttle and brake based on the difference between the current vehicle speed and the commanded vehicle speed. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 10-272963 (paragraphs [0008] and-[0012], FIG. 2)

  In the case of the conventional follow-up control, especially when the own vehicle starts following the preceding vehicle, the detection of the inter-vehicle distance between the own vehicle and the preceding vehicle and the relative speed of the preceding vehicle based on the radar survey is unstable. Because the vehicle fluctuates greatly, the commanded vehicle speed calculated based on this detection includes a large error fluctuation, and excessive acceleration / deceleration is repeated to perform unnecessary acceleration / deceleration, thereby improving follow-up running performance. There is a problem that can not be.

  An object of the present invention is to prevent unnecessary acceleration / deceleration when the host vehicle starts following the preceding vehicle and to improve the following traveling performance.

  In order to achieve the above object, the follow-up traveling control method of the present invention detects the inter-vehicle distance between the host vehicle and the preceding vehicle and the relative speed of the preceding vehicle based on the radar search ahead of the host vehicle, and based on the detection. And the command vehicle speed on the radar detection mode side of the own vehicle that maintains the detected inter-vehicle distance at the target inter-vehicle distance for follow-up traveling is calculated, and the acceleration / deceleration of the own vehicle is based on the difference between the own vehicle speed and the command vehicle speed on the radar detection mode side. The control function of the radar follow-up mode for controlling the vehicle and the calculation of a predetermined delay characteristic based on the target vehicle speed that has been set for operation, the command vehicle speed on the driver setting side that reaches the target vehicle speed with the delay characteristic is calculated, and the vehicle speed and the vehicle A driver setting mode control function that controls acceleration / deceleration of the host vehicle based on a difference from the command vehicle speed on the driver setting side, and the detected inter-vehicle distance is shortened to a predetermined control switching distance that is close to the target inter-vehicle distance. Until When the following driving of the own vehicle is controlled by the control function of the driver setting mode, and the detected inter-vehicle distance becomes shorter than the predetermined control switching distance, the following driving control of the own vehicle is controlled in the driver setting mode. The control function is switched to control of the radar tracking mode control function (claim 1).

  In the follow-up running control method of the present invention, the predetermined delay characteristic of the control function in the driver setting mode is a first-order delay characteristic (claim 2), and the operation-set target vehicle speed and control start time are When the difference from the vehicle speed at the time of setting change is more than a certain value, the time constant of the first-order lag characteristic is increased and corrected, and when the detected inter-vehicle distance is less than a predetermined semi-approach distance longer than a predetermined control switching distance, It is also characterized in that the time constant is increased and varied in proportion to the approaching change amount of the detected inter-vehicle distance to the target inter-vehicle distance.

  Next, the follow-up travel control device of the present invention searches for the front of the host vehicle to detect the inter-vehicle distance between the host vehicle and the preceding vehicle and the relative speed of the preceding vehicle, and detects the inter-vehicle distance detected by the radar. Radar follow-up mode control having a radar follow-up mode control function that calculates a command vehicle speed on the radar detection mode side of the own vehicle maintained at the target distance and controls acceleration / deceleration of the own vehicle based on the command vehicle speed on the radar detection mode side And a driver setting mode for calculating a command vehicle speed on the driver setting side by calculating a predetermined delay characteristic based on the target vehicle speed set for operation and controlling acceleration / deceleration of the host vehicle based on the command vehicle speed on the driver setting side A driver setting mode control means having a control function of: monitoring whether the detected inter-vehicle distance has become shorter than a predetermined control switching distance close to the target distance, and the detected inter-vehicle distance is the predetermined The following function of the own vehicle is controlled by the control function of the driver setting mode until the control switching distance becomes short, and the following traveling control of the own vehicle is controlled when the detected inter-vehicle distance becomes shorter than the predetermined control switching distance. Control switching means for switching from control of the control function of the driver setting mode to control of the control function of the radar follow-up mode (Claim 4).

In the following travel control device of the present invention, the predetermined delay characteristic of the control function of the driver setting mode is a first-order delay characteristic (Claim 5), and the driver setting mode control means includes:
Means for increasing and correcting the time constant of the first-order lag characteristic when the difference between the target vehicle speed set for operation and the vehicle speed at the start of control or when the setting is changed is greater than a certain value, and the detected inter-vehicle distance is longer than the predetermined control switching distance And a means for increasing the time constant in proportion to the amount of change in approach of the detected inter-vehicle distance to the target inter-vehicle distance when the distance is equal to or less than a predetermined semi-approach distance (Claim 6).

  First, according to the configuration of claims 1 and 4, for example, when the host vehicle starts following the preceding vehicle, the detected inter-vehicle distance between the host vehicle and the preceding vehicle is not more than a predetermined control switching distance close to the target inter-vehicle distance. Until the vehicle speed becomes shorter, the detection of the distance between the vehicle and the preceding vehicle based on the radar survey and the relative speed of the preceding vehicle is unstable and greatly fluctuates. Based on the command vehicle speed on the driver setting side with a predetermined delay characteristic based on the vehicle, the own vehicle is controlled to be accelerated / decelerated to the target vehicle speed without being affected by the fluctuations, and this control determines the detected inter-vehicle distance as the predetermined control switching distance. When the following is shortened, calculation of the command vehicle speed on the radar detection mode side of the own vehicle that maintains the detected inter-vehicle distance based on the radar survey at the target inter-vehicle distance results in the calculation of the vehicle speed and the command vehicle speed on the radar detection mode side. Deceleration of the vehicle is controlled on the basis of.

  Therefore, even when the vehicle starts following the preceding vehicle, even if the detection of the distance between the vehicle and the preceding vehicle based on the radar survey and the relative speed of the preceding vehicle is unstable and greatly fluctuates, The following traveling performance can be improved by avoiding unnecessary acceleration / deceleration.

  According to the second and fifth aspects of the present invention, since the predetermined delay characteristic of the control function in the driver setting mode is the first-order lag characteristic, the first-order lag characteristic can be controlled in accordance with the actual follow-up characteristic. The vehicle speed can be increased to the target vehicle speed, and the detected inter-vehicle distance can be made shorter than the predetermined control switching distance to catch up with the preceding vehicle without making the driver feel uncomfortable. The effects of claims 1 and 4 can be obtained.

  Furthermore, according to the configuration of claims 3 and 6, the difference between the target vehicle speed set for operation and the own vehicle speed at the start of control and when the setting is changed becomes a certain level or more, and the own vehicle is considerably delayed from the start of the preceding vehicle. When starting or when the preceding vehicle suddenly starts, the time constant of the primary delay characteristic is corrected to increase and the radar detection mode The sudden change in the command vehicle speed is prevented, and unnecessary acceleration / deceleration control of the host vehicle based on the command vehicle speed can be reliably prevented.

  Further, when the own vehicle approaches the preceding vehicle until the detected inter-vehicle distance becomes equal to or shorter than the predetermined semi-approach distance longer than the predetermined control switching distance by the control of the primary delay characteristic in the driver setting mode, the closer the vehicle approaches the preceding vehicle, the closer the approach is. The time constant is increased and varied, and the useless acceleration / deceleration control of the own vehicle is more reliably prevented.

  Next, in order to describe the present invention in more detail, an embodiment thereof will be described in detail with reference to FIGS.

  1 is a block diagram of an apparatus provided in the vehicle 1, FIG. 2 is a flowchart for explaining the operation of FIG. 1, FIG. 3 is a detailed flowchart of a part of FIG. 2, and FIG. FIG. 5 is a schematic diagram of control switching in FIG.

(Constitution)
1 is used to detect various operation signals such as start, stop (end) and set vehicle speed of the follow-up running control of the operation switch unit 3, and radar exploration in front of the own vehicle of the laser radar 4. As shown in FIG. Detection signals of the relative speed of the preceding vehicle based on the inter-vehicle distance between the base vehicle 1 and the preceding vehicle and the change thereof, and the detection signal of the vehicle speed of the wheel speed sensor of the vehicle state detection sensor unit 5 The following follow-up running control ECU 6 having a microcomputer configuration, a display unit 7 for displaying running information such as a liquid crystal display panel controlled by the ECU 6, and a microcomputer configuration in which a command acceleration / deceleration signal of the ECU 6 is output. A throttle control unit 8 and a brake control unit 9, and a throttle actuator 10 and a brake actuator 11 that are controlled by the control units 8 and 9 are provided.

  Further, the follow-up running control ECU 6 executes a preset follow-up running control program shown in FIGS. 2 and 3 when an ignition switch (not shown) of the host vehicle 1 is turned on. (I) to (iii) are provided.

(I) Radar following mode control means This means is based on the detection of the inter-vehicle distance between the own vehicle 1 of the laser radar 4 and the preceding vehicle and the relative speed of the preceding vehicle, and the detected inter-vehicle distance of the laser radar 4 as a target distance for the following traveling. The radar vehicle has a radar tracking mode control function for calculating the command vehicle speed on the radar mode side of the own vehicle 1 to be maintained at the above and controlling acceleration / deceleration of the vehicle based on the command vehicle speed on the radar detection mode side.

(Ii) Driver setting mode control means This means calculates a command vehicle speed on the driver setting side by calculating a predetermined delay characteristic based on the target vehicle speed that has been set for operation, and the own vehicle based on the command vehicle speed on the driver setting side. Has a control function of a driver setting mode for controlling acceleration / deceleration.

  In this embodiment, the predetermined delay characteristic is a first-order delay characteristic, and the driver setting mode control means has a difference between the target vehicle speed set for operation and the own vehicle speed at the start of control or when the setting is changed to a certain value or more. Means for correcting the time constant of the first-order lag characteristic to be increased, and when the detected inter-vehicle distance is equal to or less than a predetermined semi-approach distance longer than a predetermined control switching distance, the time constant is changed to the target inter-vehicle distance. Means for increasing and changing in proportion to the approaching change amount is provided.

(Iii) Control switching means This means monitors whether or not the detected inter-vehicle distance has become shorter than a predetermined control switching distance that is close to the target distance, and continues until the detected inter-vehicle distance is reduced to a predetermined control switching distance. When the following traveling of the own vehicle 1 is controlled by the control function of the vehicle, and the detected inter-vehicle distance becomes shorter than the predetermined control switching distance, the following traveling control of the own vehicle 1 is controlled from the control of the control function in the driver setting mode. Switch to control of the radar tracking mode control function.

  Next, the throttle control unit 8 controls the operation of the throttle actuator 10 according to the command acceleration / deceleration from the ECU 6 to control the throttle opening of the throttle valve of the host vehicle 1.

  The brake control unit 9 controls the operation of the brake actuator 11 according to the command acceleration / deceleration from the ECU 6, and controls the brake pressure of the host vehicle 1 in accordance with the brake control of the ECU 6.

  Further, the display unit 7 displays the control state of the following traveling such as the detected inter-vehicle distance, the target inter-vehicle distance, the own vehicle speed, and the like by display control of the ECU 6.

(Operation)
Next, with respect to the follow-up travel control device 2 configured as described above, the operation at the start of the follow-up travel of the host vehicle 1 will be described with reference to FIGS.

  First, for example, the preceding vehicle starts when the ignition switch is turned on and the host vehicle 1 is stopped, and the driver operates the tracking control start / stop switch as the preceding vehicle starts to start the tracking driving control. When input to the ECU 6, the process proceeds from step S1 to step S2 in FIG. 2, and the ECU 6 determines whether the detected inter-vehicle distance is equal to or less than a control switching distance (for example, 10 meters) set in advance based on various experiments. Is determined.

  When the vehicle starts, the detected inter-vehicle distance is usually longer than the control switching distance. At this time, as described above, the detection of the inter-vehicle distance between the own vehicle 1 and the preceding vehicle and the relative speed of the preceding vehicle based on the radar search is not possible. If the command vehicle speed of the host vehicle 1 is calculated based on the detection, the command vehicle speed of the host vehicle 1 is calculated. Since the calculated vehicle speed includes a large error fluctuation, the process proceeds from step S2 to step S3 in FIG. Operates the driver setting mode control function.

  The operation in this driver setting mode comprises steps S31 to S36 in FIG. 3, and basically follows the target vehicle speed (set vehicle speed) Vset set by the driver by operating the switch of the operation switch unit 3, and the initially set control. Based on the time constant Tdrv, the command vehicle speed Vref that reaches the target vehicle speed Vset with the first order lag characteristic is calculated by the calculation of the following command vehicle speed calculation formula (1) and the time constant calculation formula (2). .

Vref [k] = Kdrv × Vref [k−1] + (1−Kdrv) × Vset [k] (1) Equation Kdrv = exp (− (1 / Tdrv) × dT) (2) Equation

  In Equations (1) and (2), [k-1], [k] [k + 1] are time series operation processing times of this program that are repeated periodically, and [k] is the current time. , [K−1] indicates the immediately preceding (one time before) processing time, and [k + 1] indicates the next processing time. dT is the period (second) of the calculation process.

  Further, by executing the calculations of both equations, the ECU 6 equivalently forms a first-order lag calculation unit 6a shown in FIG.

  Specifically, in step S31 of FIG. 3, the time constant Kdrv that changes with time in the equation (1) is calculated from the calculation of the equation (2).

  Next, when the control is started, the detected inter-vehicle distance is larger than the quasi-approach distance described later, so the process proceeds from step S31 to step S33 via step S32.

  The difference (deviation) between the target vehicle speed Vset and the host vehicle speed Vi is a constant value (experimental) determined by experiments or the like in order to prevent excessive acceleration / deceleration control from occurring when the host vehicle speed Vi becomes zero. It is determined whether or not the threshold value is equal to or greater than a certain value, and if it is equal to or greater than a certain value, the process proceeds from step S33 to step S34, and the calculated time constant Kdrv is increased to a certain value or proportional to the magnitude thereof. After correcting, the process proceeds to step S35.

  On the other hand, if the difference (deviation) between the target vehicle speed Vset and the host vehicle speed Vi is smaller than a constant value (threshold value) determined by experiments or the like, the process immediately proceeds from step S33 to step S35.

  In step S35, the latest command vehicle speed Vref is calculated from the calculation of equation (1) based on the time constant Kdrv. Based on this command vehicle speed Vref, acceleration / deceleration control of the host vehicle 1 is performed in step S36.

  Specifically, a command acceleration / deceleration signal corresponding to the difference between the command vehicle speed Vref and the current host vehicle speed Vi is supplied from the ECU 6 to the control units 8 and 9, and the throttle control unit 8 responds to a throttle corresponding to the known control method. When the throttle actuator 10 is controlled to the opening and braking is required, the brake control unit 9 controls the brake actuator 11 by a known control method.

  By repeating these controls, when the vehicle speed increases and the detected inter-vehicle distance reaches a set semi-approach distance that is longer than the control switching distance, that is, the traveling inter-vehicle distance that becomes the target inter-vehicle distance a little more. Then, the process proceeds from step S32 to step S37 in FIG. 3, and the time constant Kdrv is increased and corrected in proportion to the amount of change of the detected inter-vehicle distance to the target inter-vehicle distance to be corrected, and the command vehicle speed Vref by the operation in the driver setting mode is corrected. And the acceleration / deceleration change of the own vehicle 1 is further reduced.

  Next, when the detected inter-vehicle distance reaches the control switching distance, control based on the set vehicle speed (target vehicle speed) in the driver setting mode can catch up with the preceding vehicle, but cannot perform inter-vehicle distance control. From step S2 to step S4, the control is switched from the driver setting mode control to the radar tracking mode control.

  By this radar tracking mode control, as in conventional tracking control, the ECU 6 detects the distance between the vehicle 1 of the laser radar 4 and the preceding vehicle and the relative speed of the preceding vehicle. A command vehicle speed Vref on the radar mode side of the host vehicle 1 that maintains the detected inter-vehicle distance at the target distance for following travel is calculated, and acceleration / deceleration of the host vehicle is controlled based on the command vehicle speed Vref.

  Then, during the follow-up running control, the acceleration / deceleration in the driver setting mode is performed as shown in FIG. 5 based on the determination in step S2 in FIG. 2 due to the change in the detected inter-vehicle distance based on the change in the running state of the preceding vehicle. The acceleration / deceleration in the radar follow-up mode is performed by switching.

  Therefore, especially when the host vehicle 1 starts following the preceding vehicle, the detection of the inter-vehicle distance between the host vehicle 1 and the preceding vehicle and the relative speed of the preceding vehicle based on the radar survey is unstable and greatly fluctuates. However, by the acceleration / deceleration control in the driver setting mode, it is possible to start while avoiding the influence as much as possible, to prevent unnecessary acceleration / deceleration and to improve the following traveling performance.

  Moreover, when the inter-vehicle distance approaches the target distance, the inter-vehicle distance can be maintained at the target distance by the acceleration / deceleration control in the radar follow-up mode.

  In this embodiment, since the predetermined delay characteristic of the driver setting mode is the first-order delay characteristic, the simple follow-up calculation of the above formulas (1) and (2) is used to match the actual follow-up running characteristics. Thus, the host vehicle speed Vi is increased to the target vehicle speed, and the driver does not feel uncomfortable.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit thereof. For example, the target distance and the predetermined control can be performed. The switching distance, semi-approach distance, and the like can be variously set based on experiments and the like. Further, the predetermined delay characteristic in the driver setting mode may be a first-order lag characteristic other than the first-order lag characteristic of the expressions (1) and (2), or may be a delay characteristic different from the first-order lag characteristic. . Further, laser exploration may be performed by a millimeter wave radar or the like.

  By the way, the laser radar 4 and the like shown in FIG.

It is a block diagram of one embodiment of the present invention. It is a flowchart for operation | movement description of FIG. 3 is a detailed flowchart of a part of FIG. 2. It is explanatory drawing of the calculation of the primary delay of FIG. It is a schematic diagram of the control switching of FIG.

Explanation of symbols

1 Vehicle 4 Laser Radar 6 Follow-up control ECU

Claims (6)

Based on the radar search ahead of the vehicle, the distance between the vehicle and the preceding vehicle and the relative speed of the preceding vehicle are detected, and based on the detection, the detected vehicle distance is maintained at the target vehicle distance for follow-up traveling. A radar tracking mode control function for calculating a command vehicle speed on the detection mode side and controlling acceleration / deceleration of the vehicle based on a difference between the vehicle speed and the command vehicle speed on the radar detection mode side;
By calculating a predetermined delay characteristic based on the target vehicle speed that has been set for operation, the command vehicle speed on the driver setting side that reaches the target vehicle speed is calculated using the delay characteristic, and based on the difference between the own vehicle speed and the command vehicle speed on the driver setting side. And a driver setting mode control function for controlling the acceleration / deceleration of the own vehicle,
Control the following driving of the own vehicle by the control function of the driver setting mode until the detected inter-vehicle distance becomes shorter than a predetermined control switching distance close to the target inter-vehicle distance,
When the detected inter-vehicle distance becomes shorter than or equal to the predetermined control switching distance, the control of the following driving of the own vehicle is switched from the control function control of the driver setting mode to the control function of the radar following mode. A follow-up running control method.   The follow-up running control method according to claim 1, wherein the predetermined delay characteristic of the control function in the driver setting mode is a first-order delay characteristic. In the follow-up running control method according to claim 2,
When the difference between the target vehicle speed set for operation and the vehicle speed at the start of control or when the setting is changed is more than a certain value, the time constant of the first-order lag characteristic is increased and
When the detected inter-vehicle distance is equal to or less than a predetermined quasi-approach distance longer than a predetermined control switching distance, the time constant is increased and varied in proportion to an approach change amount of the detected inter-vehicle distance to a target inter-vehicle distance. The following traveling control method. Radar that searches in front of the vehicle,
Radar detection mode side of own vehicle that detects the inter-vehicle distance between the vehicle and the preceding vehicle and the relative speed of the preceding vehicle based on the search of the radar, and maintains the detected inter-vehicle distance at the target distance for follow-up based on the detection Radar follow-up mode control means having a radar follow-up mode control function for controlling the acceleration / deceleration of the vehicle based on the command vehicle speed on the radar detection mode side;
Driver setting mode control function that calculates a command vehicle speed on the driver setting side by calculating a predetermined delay characteristic based on the target vehicle speed that has been set for operation, and controls acceleration / deceleration of the vehicle based on the command vehicle speed on the driver setting side A driver setting mode control means comprising:
It is monitored whether or not the detected inter-vehicle distance has become shorter than a predetermined control switching distance close to the target distance, and is automatically controlled by the control function of the driver setting mode until the detected inter-vehicle distance becomes shorter than the predetermined control switching distance. When the following distance of the vehicle is controlled and the detected inter-vehicle distance becomes shorter than the predetermined control switching distance, the following movement of the own vehicle is controlled from the control function of the driver setting mode to the radar following mode. And a control switching means for switching to control of the control function.   5. The follow-up travel control device according to claim 4, wherein the predetermined delay characteristic of the control function in the driver setting mode is a first-order delay characteristic. In the following traveling control device according to claim 5, in the driver setting mode control means,
Means for increasing and correcting the time constant of the first-order lag characteristic when the difference between the target vehicle speed set for operation and the start of control, and the vehicle speed at the time of setting change is a certain value
Means for increasing and varying the time constant in proportion to the amount of change in approach of the detected inter-vehicle distance to the target inter-vehicle distance when the detected inter-vehicle distance is equal to or less than a predetermined semi-approach distance longer than a predetermined control switching distance; A follow-up travel control device characterized by that.

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