JP4020137B2 - Inter-vehicle distance control device - Google Patents

Description

  The present invention relates to an inter-vehicle distance control device.

  Conventionally, the control area is set based on the sensing area of the inter-vehicle distance sensor, and when the control area is exceeded, the control area setting and release functions are provided to release the braking force and deceleration. As an inter-vehicle distance control device that performs both of the above and the like, for example, it is described in Japanese Patent Laid-Open No. 8-118996 and the one shown in FIG. 33 is known. This conventional inter-vehicle distance control device is considered to prohibit the release during the deceleration control even if the vehicle speed is lower than the release speed, and to prevent the possibility of being too close to the preceding vehicle. Is.

  However, such a conventional inter-vehicle distance control device has the following problems. As shown in the sensing angle a in FIG. 34, the radar apparatus 1 as the inter-vehicle distance sensor has an expansion w1 as it goes farther, so that the nearby sensing area w2 becomes narrower. By avoiding this, if the sensing angle is widened as shown in b in the figure, it is possible to detect a nearby preceding vehicle 2, but this increases the cost and also prevents the vehicle 3 and obstacles in the adjacent lane. In order to detect, the recognition logic of the preceding vehicles 2 and 4 becomes complicated. For this reason, a radar apparatus having a sensing angle that is too wide cannot be employed, and the radar apparatus 1 having a sensing area a is employed.

  However, when the radar apparatus 1 with a sensing angle of a is employed, when the vehicle is traveling at a low speed with a close inter-vehicle distance, the sensing angle w2 becomes narrower than the lane width w3, and the preceding vehicle 2 is removed and is not detected. Sometimes, in the low speed range below the release speed, the detection of the inter-vehicle distance is undetermined, making it difficult to execute the deceleration control based on the inter-vehicle distance. Therefore, in such a situation, that is, in the low speed range below the release speed, since detection of the inter-vehicle distance is uncertain, it is preferable to give a warning to make the driver perceive it.

  The present invention has been made in view of the above-described conventional problems. In the following inter-vehicle distance that determines the speed of the host vehicle as a function, the detection range is a predetermined value determined based on the general road width or actual traveling. An object is to provide an inter-vehicle distance control device that captures an inside road and sets it as a control area when the width is equal to or greater than a lane width detected by image processing, etc., and can control the inter-vehicle distance by reliably capturing the preceding vehicle in the control area. To do.

  The present invention also cancels the inter-vehicle distance control while gradually reducing the deceleration according to the vehicle speed or over time when the inter-vehicle distance control is canceled because the control region is exceeded. It is an object of the present invention to provide an inter-vehicle distance control device that can maintain a deceleration when deviating from a vehicle and thereby avoid sudden changes in the braking / driving behavior of the vehicle when deviating from the control region.

  It is another object of the present invention to provide an inter-vehicle distance control device capable of giving a warning to a driver in advance in a situation where inter-vehicle distance control is predicted to be canceled in the near future and preparing for the cancellation of the inter-vehicle distance control. To do.

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The present invention is characterized in that an inter-vehicle distance detecting means for detecting an inter-vehicle distance between the own vehicle and a preceding vehicle, a relative speed detecting means for detecting a relative speed with respect to the preceding vehicle, and an own vehicle speed for detecting the vehicle speed of the own vehicle. release detection means, wherein in accordance with the inter-vehicle distance detection value and the relative speed, to control the actual inter-vehicle distance to the target following distance by controlling the longitudinal force, the control When vehicle speed is equal to or less than a predetermined control release rate a vehicle distance control means for, the deceleration detecting means for detecting a deceleration of the vehicle, in the following distance control that by the inter-vehicle distance control means, and deceleration to control release is detected by the deceleration detecting means , a preset control release after deceleration, the inter-vehicle distance detection value detected by the inter-vehicle distance detecting means, and the relative speed detected by the front SL relative speed detecting means, said detected by the vehicle speed detecting means that on the basis of the vehicle speed, the vehicle speed is above And approaching prediction means for predicting prior control release that approaches within a predetermined distance preceding vehicle by a release child said distance control becomes less control release rate, preceding by releasing the inter-vehicle distance control it is that the car is following distance control device that includes a warning means for outputting an alarm when approaching within a predetermined distance.

In the above-described inter-vehicle distance control device, the inter-vehicle distance detection means detects the inter-vehicle distance between the host vehicle and the preceding vehicle, the relative speed detection means detects the relative speed with the preceding vehicle, and the inter-vehicle distance control means detects the inter-vehicle distance. The braking / driving force is controlled according to the detected value, the relative speed, and the own vehicle speed to control the actual inter-vehicle distance to the target inter-vehicle distance. In parallel with this, the deceleration detection means detects the deceleration of the host vehicle, and the approach prediction means approaches the deceleration until the control is canceled, the deceleration after the control is canceled , the inter-vehicle distance detection value, and the relative speed . Based on the own vehicle speed , if the own vehicle speed is equal to or lower than the control release speed , predict whether the preceding vehicle will be approached within a predetermined distance by canceling the inter-vehicle distance control, and cancel the inter-vehicle distance control to When approaching within a distance, an alarm is output by the alarm means.

  As a result, when it is predicted that the vehicle is too close to the preceding vehicle due to the cancellation of the inter-vehicle distance control, the driver is informed early by an alarm.

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In the above-mentioned inter-vehicle distance control device, the alarm means gives a sudden change in the braking / driving force to cause a shock that can be perceived by the driver, and even if the driver is surely perceived to cancel the inter-vehicle distance control. It doesn't matter .

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According to the present invention , it is predicted whether or not the preceding vehicle will be approached within a predetermined distance by canceling the inter-vehicle distance control, and it is predicted that the vehicle will be too close within the predetermined distance by canceling the inter-vehicle distance control. In such a case, the driver can be notified by an alarm by outputting an alarm.

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In addition , since a warning is generated by causing a sudden change in the braking / driving force to generate a shock that can be perceived by the driver, the driver can be surely perceived to cancel the inter-vehicle distance control.

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  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an inter-vehicle distance control apparatus according to a first embodiment of the present invention. The inter-vehicle distance control device according to the first embodiment detects, for example, the inter-vehicle distance da from the preceding vehicle based on a time delay from the timing at which the laser is transmitted to the timing at which the reflected light reflected from the rear portion of the preceding vehicle is reflected. The following vehicle is detected based on the temporal change in the inter-vehicle distance da detected by the inter-vehicle distance detector 11, the inter-vehicle distance detector 11 that detects the own vehicle speed va by a wheel speed pulse, and the inter-vehicle distance detector 11. A relative speed calculation unit 13 for calculating a relative speed vb with respect to the vehicle, a target inter-vehicle distance calculation unit 14 for calculating a target inter-vehicle distance db according to the vehicle speed va, and an actual inter-vehicle distance da from the relative speed vb and the vehicle speed va. The inter-vehicle distance control unit 15 that calculates the braking / driving force Ft to control the throttle, and the throttle opening sa and the block according to the braking / driving force Ft from the inter-vehicle distance control unit 15 Using a driving force control unit 16 for calculating the hydraulic pressure ba, a method of pulling a wire by a motor or a throttle actuator 17 for controlling a throttle opening using an electronic throttle, a method of controlling a piston by a motor, and others And a brake actuator 18 for controlling the brake fluid pressure.

  The inter-vehicle distance control device according to this embodiment further features, as a feature of the present invention, a lane width detection unit 19 that captures a road condition ahead of the vehicle with a camera or the like and detects a lane width lw by image processing, a target inter-vehicle distance db and a lane Sensing possibility determination unit 20 that determines whether or not a preceding vehicle can be detected in the following inter-vehicle distance from the width lw, and inter-vehicle distance control while gradually reducing the braking force according to the vehicle speed va when the host vehicle exceeds the control region. A braking force relaxation releasing unit 21 for releasing is provided.

  Next, the operation of the inter-vehicle distance control device of the first embodiment having the above configuration will be described with reference to the flowchart of FIG. The inter-vehicle distance detection unit 11 detects the inter-vehicle distance da with the preceding vehicle, and the relative speed calculation unit 13 detects the relative speed vb () of the host vehicle with respect to the preceding vehicle by temporal change of the inter-vehicle distance da, for example, time differentiation or time difference calculation. If the vehicle speed is positive, it calculates a separation tendency and if it is negative, the vehicle speed va is detected by the vehicle speed detector 12, and the vehicle speed da, the vehicle speed va, and the relative speed vb are input to the inter-vehicle distance controller 15. (Steps S11 to S13).

  Further, the target inter-vehicle distance calculation unit 14 calculates an appropriate inter-vehicle distance, that is, the target inter-vehicle distance db with respect to the host vehicle speed va detected by the vehicle speed detection unit 12 and outputs the calculated inter-vehicle distance control unit 15 and the sensing possibility determination unit 20. (Step S14).

This target inter-vehicle distance db is, for example,
[Equation 1]
Target inter-vehicle distance db = A × own vehicle speed va + B
It is calculated by the following formula.

  Here, A and B are constants, and A is set to 2 seconds (inter-vehicle time), for example, to obtain a position that reaches a certain time after the current speed of the host vehicle. Set the offset value (margin distance).

  The intervehicular distance control unit 15 calculates the braking / driving force Ft from the input relative speed vb, intervehicular distance da, and target intervehicular distance db according to the following equation (2), and supplies the braking / driving force Ft to the driving force control unit 16.

[Equation 2]
Target braking / driving force Ft = P1 × (vehicle distance da−target vehicle distance db)
+ P2 × relative speed vb
Here, P1 and P2 are control gains.

  The driving force control unit 16 calculates and obtains the throttle opening sa and the brake fluid pressure ba based on the control characteristics shown in FIGS. 3 and 4 according to the applied braking / driving force Ft (step S15).

  First, the engine drive shaft torque Te is calculated from the target braking / driving force Ft and the transmission gear ratio Gr by the following equation (3).

[Equation 3]
Engine shaft torque Te = (target braking / driving force Ft × tire radius)
/ (Gear ratio Gr × 9.8)
Then, the throttle opening degree sa is selected from the engine shaft torque Te and the engine speed Ne according to the engine map shown in FIG.

  The brake fluid pressure ba is calculated by the following equation (4).

[Equation 4]
Brake fluid pressure ba = −drive force Ft / Bp
Here, Bp is a braking force conversion constant.

  On the other hand, for example, the lane width detection unit 19 captures a scene ahead of the road with a camera, detects the distance between the left and right road white lines, that is, the lane width lw by image processing, and supplies the detected distance to the sensing possibility determination unit 20 (step). S16). Then, the sensing possibility determination unit 20 compares whether or not the detection width w of the inter-vehicle distance detection unit 11 in the following inter-vehicle distance L is smaller than the actual lane width lw (step S17).

  Here, if the inter-vehicle distance detection width w in the following inter-vehicle distance is larger than the actual lane width lw, it is determined that the preceding vehicle can be sensed, and the step is not intervened in the braking / driving force Ft output from the inter-vehicle distance control unit 15. The process proceeds to S19.

  In step S19, normally, the throttle opening sa and the brake hydraulic pressure ba calculated by the driving force control unit 16 are given to the throttle actuator 17 and the brake actuator 18, respectively, and command values given to the throttle actuator 17 and the brake actuator 18 are given. Thus, the throttle opening and the brake fluid pressure are actuated so as to coincide with each other, the own vehicle speed is adjusted, and control is performed so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  However, if the detection width w of the inter-vehicle distance detection unit 11 in the following inter-vehicle distance is smaller than the lane width lw, the sensing possibility determination unit 20 determines that the preceding vehicle cannot be sensed in step S17 and determines the braking force relaxation control command. Is output to the braking force relaxation release unit 21.

  Here, as shown in FIG. 5, when the detection width w of the inter-vehicle distance detection unit 11 in the following inter-vehicle distance is a detection angle (sensing angle) θ and the following inter-vehicle distance L, the following equation 5 is obtained.

[Equation 5]
Detection width w = 2L tan (θ / 2)
If the sensing possibility determination unit 20 determines that sensing cannot be performed, the braking force relaxation release unit 21 calculates a braking force command value Ft2 from the vehicle speed detection value according to the following equation (6) (step S18).

[Equation 6]
Braking force command value Ft2
= Braking force Ft1 according to equation 2 just before sensing impossible
+ C1 x (speed va1-vehicle speed detection value va2 when sensing is impossible)
However, C1 is a constant.

  The inter-vehicle distance control unit 15 outputs the applied braking force command value Ft2 as the braking / driving force Ft to the driving force control unit 16 to control the braking force (steps S19 and S20).

  If the braking force command value Ft2 is calculated by the above equation (6) and the driving force is controlled as a new braking / driving force command value Ft, the value Ft1 (original Ft) calculated by the equation (2) at the control release speed is obtained. It is connected smoothly and continuously, and the braking force can be weakened gradually.

  In the first embodiment, when the inter-vehicle distance control is canceled, the braking force Ft calculated by the inter-vehicle distance control unit 15 is gradually relaxed. Instead of this, the following equation (7) is used. In addition, it is possible to employ control in which the braking force command value Ft is gradually relaxed according to time.

[Equation 7]
Braking force command value Ft2
= Braking force Ft1 according to equation 2 just before sensing impossible
+ C2 x elapsed time t from sensing impossible judgment t
However, C2 is a constant.

  Next, an inter-vehicle distance control apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is characterized in that, compared to the first embodiment shown in FIG. 1, the inter-vehicle distance control unit 15a receives an inter-vehicle distance da, a target inter-vehicle distance db, an own vehicle speed va, and a relative speed. The vehicle target speed vc and deceleration α required to make the actual inter-vehicle distance da coincide with the target inter-vehicle distance db by vb are calculated, and the vehicle speed control unit 15b requires the braking / driving force required for the target speed vc. Ft is calculated and applied to the driving force control unit 16, and the driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba in the same manner as in the first embodiment, so that the throttle actuator 17 and the brake actuator 18 are Further, the deceleration relaxation release unit 21a in place of the braking force relaxation release unit 21 in the first embodiment is configured to control the sensing possibility determination unit 20 to determine the sensing impossible result. Only, the adjusted by a calculation described later deceleration α1 computed vehicle distance control section 15a, lies in that to return the distance control unit 15a. In the second embodiment, the elements other than those described above are the same as those in the first embodiment shown in FIG.

  In the inter-vehicle distance control apparatus according to the second embodiment, as shown in the flowchart of FIG. 7, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da and the relative speed calculation unit 13 as in the first embodiment. To calculate the relative speed vb, the vehicle speed detecting unit 12 detects the own vehicle speed va, and the target inter-vehicle distance calculating unit 14 calculates the target inter-vehicle distance db (steps S11 to S14).

  The inter-vehicle distance control unit 15a calculates a target vehicle speed vc for controlling to the target inter-vehicle distance db obtained by the following equation (8) from the input relative speed vb, the inter-vehicle distance da, and the target inter-vehicle distance db. (Step S15a).

[Equation 8]
Target vehicle speed vc = F1 × (vehicle distance da−target vehicle distance db)
+ F2 × relative speed vb + (own vehicle speed va + relative speed vb)
Here, F1 and F2 are control gains, and (own vehicle speed va + relative speed vb) is the speed of the preceding vehicle.

The target vehicle speed vc obtained by the equation (8) is a speed for making the inter-vehicle distance da coincide with the target inter-vehicle distance db and making the vehicle speed va coincide with the speed of the preceding vehicle. The vehicle speed control unit 15b calculates a target braking / driving force Ft for making the host vehicle speed va coincide with the given target vehicle speed vc, for example, using the following equation (9).

  However, G1, G2, and G3 are control gains.

  Then, the driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba according to the target driving force Ft, as in the first embodiment.

Further, the inter-vehicle distance control unit 15a calculates the deceleration α1 by time-differentiating the target vehicle speed vc generated by the inter-vehicle distance control as shown in the following equation (10) (step S15b).

  Next, as in the first embodiment, the lane width detection unit 19 detects the lane width lw (step S16), and the sensing possibility determination unit 20 detects the detection width of the inter-vehicle distance detection unit 11 at the following inter-vehicle distance L. It is compared whether w is smaller than the actual lane width lw (step S17).

  If the inter-vehicle distance detection width w in the following inter-vehicle distance is larger than the actual lane width lw, it is determined that the preceding vehicle can be sensed, and the process proceeds to step S19. As in the first embodiment, the driving force control unit 16 The throttle opening and brake fluid pressure are controlled so as to match the calculated throttle opening sa and the brake fluid pressure ba to adjust the own vehicle speed and follow the preceding vehicle while maintaining the target inter-vehicle distance. Control is performed (steps S19 and S20).

  However, if the sensing possibility determination unit 20 determines that the preceding vehicle cannot be sensed in step S17 because the detection width w of the inter-vehicle distance detection unit 11 in the following inter-vehicle distance is smaller than the lane width lw, the deceleration relaxation control command Is output to the deceleration relaxation releasing unit 21a.

  The deceleration relaxation releasing unit 21a calculates the deceleration command value α2 from the deceleration command value α1 from the inter-vehicle distance control unit 15a by the following equation (11) (step S18a).

[Equation 11]
Deceleration command value α2
= Deceleration α1 according to Equation 10 immediately before sensing impossible
+ D1 × (speed when sensing is impossible−vehicle speed detection value va)
However, D1 is a constant.

  The inter-vehicle distance control unit 15a calculates the target vehicle speed vc2 again based on the adjusted deceleration force command value α2 that is given and outputs it to the vehicle speed control unit 15b. Thereafter, as in the case of the normal control, the vehicle speed control unit The braking / driving force Ft2 with respect to the target vehicle speed vc2 is calculated at 15b, and the throttle actuator 17 and the brake actuator 18 are controlled by the driving force control unit 16 to perform deceleration control (steps S19 and S20).

  In this way, if the deceleration command value α2 is calculated by Equation 11 and a new braking force command value Ft2 based on this is calculated and the driving force is controlled, the braking force calculated by Equation 2 at the control release speed is obtained. Ft1 (original Ft) is connected smoothly and continuously, and the deceleration can be gradually reduced.

  In the second embodiment, when the vehicle speed control is released, the deceleration calculated by the inter-vehicle distance control unit 15a is gradually relaxed. Instead of this, the following equation 12 is used to reduce the deceleration. Control in which the speed command value α2 is gradually relaxed according to time can also be employed.

[Equation 12]
Deceleration command value α2
= Deceleration α1 according to Equation 10 immediately before sensing impossible
+ D2 × Elapsed time t from sensing impossible judgment
However, D2 is a constant.

  In this case, the target vehicle speed vc2 is recalculated from the deceleration command value α2 by the following equation (13), and deceleration control is performed based on this.

[Equation 13]
Target vehicle speed vc2 = Target vehicle speed vc according to equation (8) just before sensing impossible
+ Deceleration command value α2 × Elapsed time t
According to the first and second embodiments, the control region is set according to the sensing limit, and the braking force or the deceleration is gradually increased according to the vehicle speed or the passage of time even if the host vehicle exceeds the control region. Since control is released while relaxing,
(1) The control area can be set according to the sensing limit, and the traveling control according to the sensor signal can be performed reliably.
(2) Rather than canceling the deceleration control suddenly in the area exceeding the sensing limit, the deceleration control can be maintained in the area exceeding the sensing limit.
(3) When it becomes the control release area, it is possible to prevent the deterioration of the ride comfort by using the data immediately before becoming the release area,
(4) The control can be gradually stopped and the control is released in the low speed range before the control is completely released (during braking force relaxation or deceleration relaxation release). Can do.

  Next, an inter-vehicle distance control apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The feature of the third embodiment is that a release speed setting unit 22 is provided instead of the lane width detection unit 19 and the sensing possibility determination unit 20 is replaced with the first embodiment shown in FIG. The other components are the same as those in the first embodiment in that the speed control region determination unit 23 is provided.

  The release speed setting unit 22 holds a control release speed value vd set in advance. The release speed vd is a value obtained as follows. Assuming that the value is H using a general road width, the inter-vehicle distance L at which the inter-vehicle distance detection unit 11 has a detection width w greater than or equal to the road width by the sensing angle θ is as described in the first embodiment. In addition, it is obtained from the equation (5), and is equal to or greater than L in the following equation (14).

[Formula 14]
L = H / (2.tan (θ / 2))
Therefore, the speed to be controlled to the inter-vehicle distance L is obtained from Equation 1 and set to the release speed vd.

[Equation 15]
Release speed vd = (LB) / A
However, A and B are constants used in Equation 1.

  The speed control region determination unit 23 compares the vehicle speed detection value va from the vehicle speed detection unit 12 with the release speed vd from the release speed setting unit 21, and continues the inter-vehicle distance control if the vehicle speed detection value va is larger than the release speed. When the vehicle speed detection value va becomes equal to or less than the release speed, a braking force relaxation control command is output to the braking force relaxation release unit 21.

  Next, the operation of the inter-vehicle distance control apparatus according to the third embodiment will be described with reference to the flowchart of FIG. In the normal inter-vehicle distance control, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da, the relative speed calculation unit 13 calculates the relative speed vb, as in the processing of the first embodiment shown in FIG. The host vehicle speed va is detected by the vehicle speed detector 12, and the target inter-vehicle distance db is calculated by the target inter-vehicle distance calculator 14 and input to the inter-vehicle distance controller 15 (steps S11 to S14).

  The intervehicular distance control unit 15 calculates the braking / driving force Ft from the input relative speed vb, intervehicular distance da, and target intervehicular distance db, and gives the driving force control unit 16 (step S15).

  Then, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd. If the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued and the vehicle speed detection value va becomes less than the release speed. If so, a braking force relaxation control command is output to the braking force relaxation release unit 21 (step S17a).

  When the speed control cancellation determination unit 23 determines to continue the inter-vehicle distance control in step S17a, the braking force relaxation cancellation unit 21 intervenes in the braking / driving force Ft output from the inter-vehicle distance control unit 15 as in the first embodiment. First, the throttle opening sa and the brake hydraulic pressure ba calculated by the driving force control unit 16 are given to the throttle actuator 17 and the brake actuator 18, respectively, and the throttle actuator 17 and the brake actuator 18 open the throttle so as to coincide with the given command values. The brake fluid pressure is actuated to adjust the own vehicle speed, and control is performed so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  On the other hand, when the speed control cancellation determination unit 23 determines that the braking force relaxation release is determined in step S17a, the braking force relaxation cancellation unit 21 determines the vehicle speed detection value va according to the following equation 16 as in the first embodiment. The braking force command value Ft2 is calculated from (step S18), and the inter-vehicle distance control unit 15 outputs the applied braking force command value Ft2 as the braking / driving force Ft to the driving force control unit 16 to control the braking force (step S19). , S20).

[Equation 16]
Braking force command value Ft2
= Braking force Ft1 according to equation 2 just before reaching the release speed
+ C1 × (speed va1 at the time of release speed arrival determination−vehicle speed detection value va2)
However, C1 is a constant.

  Thus, according to the third embodiment, when the host vehicle speed va becomes equal to or lower than the preset release speed vd, the braking force command value Ft2 is calculated by the above-described equation 16, and this is applied to a new braking / driving operation. By controlling the driving force as the force command value Ft, the value Ft1 (original Ft) calculated by the formula 2 at the control release speed vd can be smoothly and continuously connected, and the braking force can be gradually reduced according to the vehicle speed. it can.

  In the third embodiment described above, the braking force Ft calculated by the inter-vehicle distance control unit 15 when the inter-vehicle distance control is released is gradually reduced according to the vehicle speed. As in the case of the embodiment, it is possible to employ control in which the braking force command value Ft is gradually relaxed according to time by the following equation (17).

[Equation 17]
Braking force command value Ft2
= Braking force Ft1 according to equation 2 just before reaching the release speed
+ C2 × Elapsed time t from determination of release speed arrival
However, C2 is a constant.

  Next, the inter-vehicle distance according to the fourth embodiment of the present invention will be described with reference to FIGS. The feature of the fourth embodiment is that the inter-vehicle distance control unit 15a is different from the third embodiment shown in FIG. 8 in the same way as the second embodiment with respect to the first embodiment. Based on the input inter-vehicle distance da, the target inter-vehicle distance db, the own vehicle speed va, and the relative speed vb, the target vehicle speed vc and the deceleration α necessary for making the actual inter-vehicle distance da coincide with the target inter-vehicle distance db are calculated. The vehicle speed control unit 15b calculates the braking / driving force Ft necessary for the target speed vc and applies the braking / driving force Ft to the driving force control unit 16, and the driving force control unit 16 controls the throttle opening as in the first embodiment. sa and the brake hydraulic pressure ba are calculated to control the throttle actuator 17 and the brake actuator 18, and the deceleration relaxation release unit 21a in place of the braking force relaxation release unit 21 in the third embodiment is used as a speed. Upon receiving the determination result of the control release rate reaches the control region determining unit 23 adjusts the deceleration α1 computed vehicle distance control section 15a, lies in that to return the distance control unit 15a. In the fourth embodiment, the elements other than those described above are the same as those in the third embodiment shown in FIG.

  In the inter-vehicle distance control device according to the fourth embodiment, as shown in the flowchart of FIG. 11, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da and the relative speed calculation unit 13 as in the third embodiment. To calculate the relative speed vb, the vehicle speed detecting unit 12 detects the own vehicle speed va, and the target inter-vehicle distance calculating unit 14 calculates the target inter-vehicle distance db (steps S11 to S14).

  The inter-vehicle distance control unit 15a calculates the target vehicle speed vc from the input relative speed vb, inter-vehicle distance da, and target inter-vehicle distance db according to the equation 8 described in the second embodiment (step S15a). The inter-vehicle distance control unit 15a also calculates the deceleration α1 by differentiating the target vehicle speed vc generated by the inter-vehicle distance control with respect to time based on the equation (10) (step S15b).

  The vehicle speed control unit 15b calculates the target braking / driving force Ft for making the host vehicle speed va coincide with the given target vehicle speed vc by the above-described equation (9). Then, the driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba according to the target driving force Ft, as in the third embodiment.

  Next, as in the third embodiment, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd, and if the vehicle speed detection value va is greater than the release speed, the inter-vehicle distance control is continued. If the vehicle speed detection value va becomes equal to or less than the release speed, a deceleration relaxation control command is output to the deceleration relaxation release unit 21a (step S17a).

  When the speed control cancellation determination unit 23 determines to continue the inter-vehicle distance control in step S17a, the deceleration relaxation cancellation unit 21a does not intervene in the target vehicle speed vc output from the inter-vehicle distance control unit 15a, and is calculated by the vehicle speed control unit 15b. The driving force control unit 16 calculates the throttle opening sa and the brake fluid pressure ba with respect to the braking / driving force Ft and applies them to the throttle actuator 17 and the brake actuator 18 respectively to control the throttle opening and the brake fluid pressure. The own vehicle speed is adjusted, and control is performed so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  On the other hand, when the speed control cancellation determination unit 23 determines that the deceleration relaxation cancellation is performed in step S17a, the deceleration relaxation control command is output to the deceleration relaxation cancellation unit 21a, and the deceleration relaxation cancellation unit 21a is the inter-vehicle distance control unit. Similarly to the second embodiment, the deceleration command value α2 from the deceleration command value α1 from 15a is calculated according to Equation 18 (step S18a).

[Equation 18]
Deceleration command value α2
= Deceleration α1 according to Equation 10 immediately before reaching the release speed arrival determination
+ D1 × (speed at the time of release speed arrival determination−vehicle speed detection value va)
However, D1 is a constant.

  The inter-vehicle distance control unit 15a calculates the target vehicle speed vc2 again based on the supplied adjusted deceleration force command value α2 and outputs it to the vehicle speed control unit 15b (step S18b). Thereafter, as in the case of normal control, The vehicle speed control unit 15b calculates the braking / driving force Ft2 with respect to the target vehicle speed vc2, and the driving force control unit 16 controls the throttle actuator 17 and the brake actuator 18 to perform deceleration control (steps S19 and S20).

  In this way, if the deceleration command value α2 is calculated by the equation (18), and the new braking force command value Ft2 based on this is calculated and the driving force is controlled, the braking force calculated by the equation (2) at the control release speed is obtained. Ft1 (original Ft) is connected smoothly and continuously, and the deceleration can be gradually reduced.

  In the fourth embodiment, when the vehicle speed control is released, the deceleration calculated by the inter-vehicle distance control unit 15a is gradually relaxed. However, as in the case of the second embodiment, It is also possible to employ control in which the deceleration command value α2 is gradually relaxed according to time by the following equation (19).

[Equation 19]
Deceleration command value α2
= Deceleration α1 according to Equation 10 immediately before reaching the release speed arrival determination
+ D2 × elapsed time t from determination of release speed arrival
However, D2 is a constant.

  In this case, the target vehicle speed vc2 is recalculated from the deceleration command value α2 by the following equation (20), and deceleration control is performed based on this.

[Equation 20]
Target vehicle speed vc2 = target vehicle speed vc according to equation (8) just before the determination of reaching the release speed
+ Deceleration command value α2 × Elapsed time t
According to the inter-vehicle distance control devices of the third and fourth embodiments, the control is canceled while gradually reducing the braking force or deceleration according to the vehicle speed or time even if the host vehicle exceeds the control region. Thus, the effects (1) to (4) are obtained as in the first and second embodiments.

  Next, an inter-vehicle distance control apparatus according to a fifth embodiment of the present invention will be described with reference to FIGS. The feature of the fifth embodiment is that a braking force holding portion 25 is provided instead of the braking force relaxation releasing portion 24 with respect to the third embodiment shown in FIG. Is the same as that of the third embodiment.

  When the speed control area determination unit 23 outputs a braking force holding command when the vehicle speed detection value va becomes equal to or less than the release speed vd based on the control area determination, the braking force holding unit 25 outputs the inter-vehicle distance control unit 15 at the time of this determination. The braking force holding value Ft2 (= Ft1) is output to the driving force control unit 16 so as to hold the braking force Ft1 (= Ft).

  Next, the operation of the inter-vehicle distance control apparatus according to the fifth embodiment will be described with reference to the flowchart of FIG. In the normal inter-vehicle distance control, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da, the relative speed calculation unit 13 calculates the relative speed vb, as in the processing of the first embodiment shown in FIG. The host vehicle speed va is detected by the vehicle speed detector 12, the target inter-vehicle distance db is calculated by the target inter-vehicle distance calculator 14, and is output to the inter-vehicle distance controller 15 (steps S 11 to S 14). The driving force Ft is calculated and given to the driving force control unit 16 (step S15).

  Then, the speed control release determination unit 23 compares the vehicle speed detection value va and the release speed vd as in the third embodiment, and if the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued. If the detected value va is equal to or lower than the release speed, a braking force holding control command is output to the braking force holding unit 25 (step S17a).

  When the speed control release determining unit 23 determines to continue the inter-vehicle distance control in step S17a, the braking force holding unit 25 does not intervene in the braking / driving force Ft output from the inter-vehicle distance control unit 15, and the calculation of the driving force control unit 16 is performed. The throttle opening sa and the brake hydraulic pressure ba are applied to the throttle actuator 17 and the brake actuator 18 respectively, and the throttle opening and the brake hydraulic pressure are operated so that the throttle actuator 17 and the brake actuator 18 coincide with the command values given. The own vehicle speed is adjusted, and control is performed so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  On the other hand, when the speed control release determination unit 23 determines that the braking force is held in step S17a, the braking force holding unit 25 holds the braking force command value Ft1 immediately before the release speed arrival determination obtained from the inter-vehicle distance control unit 15. This is output to the driving force control unit 16 as a braking force command value Ft (step S18c), and the braking force is controlled (steps S19 and S20).

  Thus, according to the fifth embodiment, when the host vehicle speed va becomes equal to or lower than the preset release speed vd, the braking force command value Ft1 immediately before the release speed arrival determination is held, and this is used as the braking / driving force command. By controlling the driving force as the value Ft, the braking force corresponding to the immediately preceding vehicle speed va is maintained even if the host vehicle exceeds the control region, so that the braking force is not suddenly released.

  Next, the inter-vehicle distance according to the sixth embodiment of the present invention will be described with reference to FIGS. The feature of the sixth embodiment is that the inter-vehicle distance control unit 15a is different from the fifth embodiment shown in FIG. 12 in the same way as the fourth embodiment with respect to the third embodiment. Based on the input inter-vehicle distance da, the target inter-vehicle distance db, the own vehicle speed va, and the relative speed vb, the target vehicle speed vc and the deceleration α necessary for making the actual inter-vehicle distance da coincide with the target inter-vehicle distance db are calculated. The vehicle speed control unit 15b calculates the braking / driving force Ft necessary for the target speed vc and applies the braking / driving force Ft to the driving force control unit 16, and the driving force control unit 16 controls the throttle opening as in the first embodiment. The throttle actuator 17 and the brake actuator 18 are controlled by calculating sa and the brake hydraulic pressure ba. Further, a deceleration holding unit 25a in place of the braking force holding unit 25 in the fifth embodiment has a speed control range. In response to control release rate reaches the determination result of the determination unit 23 lies in that to hold the deceleration α1 computed vehicle distance control section 15a to control release immediately before. In the sixth embodiment, the elements other than those described above are the same as those of the fifth embodiment shown in FIG.

  In the inter-vehicle distance control device according to the sixth embodiment, as shown in the flowchart of FIG. 15, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da as in the fourth embodiment shown in the flowchart of FIG. Then, the relative speed calculator 13 calculates the relative speed vb, the vehicle speed detector 12 detects the host vehicle speed va, and the target inter-vehicle distance calculator 14 calculates the target inter-vehicle distance db (steps S11 to S14).

  Then, the inter-vehicle distance control unit 15a calculates the target vehicle speed vc according to the above equation (8) (step S15a). Further, the inter-vehicle distance control unit 15a also calculates the deceleration α1 by differentiating the target vehicle speed vc generated by the inter-vehicle distance control with respect to time using the above-described equation (10) (step S15b).

  Next, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd, and if the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued, and the vehicle speed detection value va is less than the release speed. If this is the case, a deceleration holding control command is output to the deceleration holding unit 25a (step S17a).

  When the speed control release determining unit 23 determines to continue the inter-vehicle distance control in step S17a, the deceleration holding unit 25a does not intervene in the target vehicle speed vc output from the inter-vehicle distance control unit 15a, and is the same as in the fourth embodiment. Then, the vehicle speed control unit 15b calculates the braking / driving force Ft, and applies the throttle opening sa and the brake hydraulic pressure ba calculated by the driving force control unit 16 to the throttle actuator 17 and the brake actuator 18, respectively. Then, the brake fluid pressure is controlled to increase or decrease the own vehicle speed, and control is performed so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  On the other hand, when the speed control release determining unit 23 determines that the deceleration is held in step S17a, the deceleration holding control command is output to the deceleration holding unit 25a, and the deceleration holding unit 25a is sent from the inter-vehicle distance control unit 15a. The deceleration command value α1 immediately before reaching the release speed is held and returned to the inter-vehicle distance control unit 15a as α2 (= α1) (step S18d).

  As in the second embodiment, the inter-vehicle distance control unit 15a calculates the target vehicle speed vc2 based on the deceleration force command value α2 (= α1) given from the deceleration holding unit 25a, and outputs it to the vehicle speed control unit 15b. (Step S18b) Thereafter, as in the case of the normal control, the vehicle speed control unit 15b calculates the braking / driving force Ft2 for the target vehicle speed vc2, and the driving force control unit 16 controls the throttle actuator 17 and the brake actuator 18. To control deceleration (steps S19 and S20).

  In this way, in the sixth embodiment, when the vehicle speed control is released, the deceleration calculated by the inter-vehicle distance control unit 15a is maintained, and the driving force is controlled based on this, so that the host vehicle exceeds the control region. However, the deceleration corresponding to the immediately preceding vehicle speed va is maintained so that the deceleration is not released suddenly.

According to the inter-vehicle distance control device of the fifth and sixth embodiments, the braking force or deceleration is maintained even if the host vehicle exceeds the control region.
(1) Deceleration control can be maintained even in areas that exceed the sensing limit.
(2) When the control release area is entered, deterioration of riding comfort can be prevented by using data immediately before the release area.

  Next, an inter-vehicle distance control apparatus according to a seventh embodiment of the present invention will be described with reference to FIGS. The feature of the seventh embodiment is that a braking force adjusting unit 26 is provided instead of the braking force relaxation releasing unit 21 in the third embodiment shown in FIG. The vehicle functions to adjust the braking force by a method described later when the host vehicle exceeds the control region. Other components are the same as those in the third embodiment.

  Next, the operation of the seventh embodiment will be described with reference to the flowchart of FIG. In the normal inter-vehicle distance control, as in the process of the third embodiment shown in FIG. 8, the inter-vehicle distance da is detected, the relative speed vb is calculated, the own vehicle speed va is detected, and the target inter-vehicle distance db Is calculated and applied to the inter-vehicle distance control unit 15 (steps S11 to S14), and the inter-vehicle distance control unit 15 calculates the braking / driving force Ft and supplies it to the driving force control unit 16 (step S15).

  Then, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd. If the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued and the vehicle speed detection value va becomes less than the release speed. If so, a braking force adjustment control command is output to the braking force adjustment unit 26 (step S17a).

  When the speed control release determining unit 23 determines to continue the inter-vehicle distance control in step S17a, the braking force adjusting unit 26 does not intervene in the braking / driving force Ft output from the inter-vehicle distance control unit 15 as in the third embodiment. Then, each of the throttle actuator 17 and the brake actuator 18 is operated so as to coincide with the throttle opening sa calculated by the driving force control unit 16 and the brake hydraulic pressure ba to adjust the own vehicle speed, and the own vehicle is the target with respect to the preceding vehicle. Control is performed so as to follow while maintaining the inter-vehicle distance db (steps S19 and S20).

  On the other hand, when the speed control cancellation determination unit 23 determines that the braking force adjustment control is performed in step S17a, the braking force adjustment unit 26 determines the following number according to the inter-vehicle distance da and the relative speed vb immediately before exceeding the control region. Based on the equation (21), the braking force Ft1 (= Ft) is adjusted to be relaxed, held or increased, and Ft2 obtained as a result of the adjustment is given to the driving force control unit 16 (step S18e).

[Equation 21]
(I) Relative speed vb ≦ predetermined value 1 (approaching the preceding vehicle) (i-1) inter-vehicle distance va ≦ predetermined value 3
The braking force is increased and controlled by the calculation of the following equation (22).

(I-2) Inter-vehicle distance va> predetermined value 3
The braking force Ft1 immediately before reaching the release speed is held.

(Ii) In the case of relative speed vb ≧ predetermined value 2 (away from the preceding vehicle)
Regardless of the inter-vehicle distance da, the braking force is relaxed and controlled by the calculation of Equation (16).

(Iii) Predetermined value 2> relative speed vb> predetermined value 1 (cruising to the preceding vehicle) (iii-1) inter-vehicle distance da ≦ predetermined value 4
The braking force Ft1 immediately before reaching the release speed is held.

(Iii-2) Inter-vehicle distance da> predetermined value 4
The braking force is relaxed and controlled by the calculation of equation (16).

  FIG. 18 shows the respective deceleration patterns when these are relaxed, retained, and enhanced. When increasing the braking force, the braking force is calculated by the following equation (22).

[Equation 22]
Braking force command value Ft2
= Braking force according to Equation 2 just before reaching the release speed
-C3 x (speed va1 when the release speed is reached-vehicle speed detection value va2)
However, C3 is a constant.

  Thus, when the braking force adjusting unit 26 calculates and determines the braking force command value Ft2 in step S18e, the inter-vehicle distance control unit 15 uses the applied braking force command value Ft2 as the braking / driving force Ft to the driving force control unit 16. The braking force is output and the braking force is controlled (steps S19 and S20).

  In this way, according to the seventh embodiment, by calculating the braking force command value Ft2 according to the equation (22), the value calculated according to the equation (2) is smoothly and continuously connected at the control release speed. The braking force can be increased.

  In the seventh embodiment as well, as in the case of the third embodiment, when the braking force command value Ft2 is increased, a value corresponding to time as shown in the following Expression 23 is used. It can also be used.

[Equation 23]
Braking force command value Ft2
= Braking force according to Equation 2 just before reaching the release speed
-C4 x elapsed time t since the release speed was reached
However, C4 is a constant.

  Next, an inter-vehicle distance control apparatus according to an eighth embodiment of the present invention will be described with reference to FIGS. As in the case of the fourth embodiment shown in FIG. 10 with respect to the third embodiment shown in FIG. 8, the eighth embodiment is the same as that in the seventh embodiment shown in FIG. Instead of the power adjusting unit 26, a deceleration adjusting unit 26a is provided. The deceleration adjusting unit 26a functions to adjust the deceleration by a method described later when the host vehicle exceeds the control region.

  Next, the operation of the eighth embodiment will be described with reference to the flowchart of FIG. In the normal inter-vehicle distance control, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da and the relative speed calculation unit 13 calculates the relative speed vb, as in the process of the fourth embodiment shown in FIG. The host vehicle speed va is detected by the vehicle speed detector 12, the target inter-vehicle distance db is calculated by the target inter-vehicle distance calculator 14 (steps S 11 to S 14), and the inter-vehicle distance controller 15 a receives the input relative speed vb and inter-vehicle distance da. The target vehicle speed vc is calculated from the target inter-vehicle distance db (step S15a). The inter-vehicle distance control unit 15a also calculates the deceleration α1 by time-differentiating the target vehicle speed vc generated by the inter-vehicle distance control (step S15b).

  The vehicle speed control unit 15b calculates the target braking / driving force Ft for making the host vehicle speed va coincide with the given target vehicle speed vc by the above-described equation (9). Then, the driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba according to the target driving force Ft, as in the third embodiment.

  Next, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd, and if the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued, and the vehicle speed detection value va is less than the release speed. If this is the case, a deceleration adjustment control command is output to the deceleration adjustment unit 26a (step S17a).

  If the speed control release determining unit 23 determines in step S17a that the inter-vehicle distance control is to be continued, the deceleration adjusting unit 26a does not intervene in the target vehicle speed vc output from the inter-vehicle distance control unit 15a, and the control calculated by the vehicle speed control unit 15b. The driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba with respect to the driving force Ft, and applies them to the throttle actuator 17 and the brake actuator 18 respectively, and controls the throttle opening and the brake hydraulic pressure to control the driving force Ft. The vehicle speed is adjusted so that the own vehicle follows the preceding vehicle while maintaining the target inter-vehicle distance (steps S19 and S20).

  On the other hand, when the speed control release determination unit 23 determines that the control range has been exceeded in step S17a, the deceleration adjustment control command is output to the deceleration adjustment unit 26a, and the deceleration adjustment unit 26a is transmitted from the inter-vehicle distance control unit 15a. In response to the deceleration command value α1, the calculation to increase, hold or relax the deceleration command value α1 is performed based on the following equation (24) according to the inter-vehicle distance da1 and the relative speed vb1 immediately before reaching the release speed. Then, the adjustment result is output to the inter-vehicle distance control unit 15a as a deceleration command α2 (step S18f).

[Equation 24]
(I) Relative speed vb ≦ predetermined value 1 (approaching the preceding vehicle) (i-1) inter-vehicle distance va ≦ predetermined value 3
The deceleration is increased and controlled by the calculation of the following equation (25).

(I-2) Inter-vehicle distance va> predetermined value 3
The deceleration α1 immediately before reaching the release speed is held.

(Ii) In the case of relative speed vb ≧ predetermined value 2 (away from the preceding vehicle)
Regardless of the inter-vehicular distance da, the deceleration is mitigated by the calculation of equation (18).

(Iii) Predetermined value 2> relative speed vb> predetermined value 1 (cruising to the preceding vehicle) (iii-1) inter-vehicle distance da ≦ predetermined value 4
The deceleration α1 immediately before reaching the release speed is held.

(Iii-2) Inter-vehicle distance da> predetermined value 4
The deceleration is relaxed by the calculation of Equation (18).

  In the case of increasing the deceleration, a value obtained by obtaining the deceleration α2 by the following equation (25) is used.

[Equation 25]
Deceleration command value α2
= Deceleration α1 according to Equation 10 immediately before reaching the release speed arrival determination
−D3 × (speed at the time of release speed arrival determination−vehicle speed detection value va)
However, D3 is a constant.

  The inter-vehicle distance control unit 15a calculates the target vehicle speed vc2 again based on the supplied adjusted deceleration force command value α2 and outputs it to the vehicle speed control unit 15b (step S18b). Thereafter, as in the case of normal control, The vehicle speed control unit 15b calculates the braking / driving force Ft2 with respect to the target vehicle speed vc2, and the driving force control unit 16 controls the throttle actuator 17 and the brake actuator 18 to perform deceleration control (steps S19 and S20).

  In this way, according to the eighth embodiment, by calculating the deceleration command value α2 according to Equation 24, the value calculated with Equation 10 at the control release speed is smoothly and continuously connected, and gradually Deceleration can be strengthened.

  In the eighth embodiment, as in the case of the fourth embodiment, when the deceleration command value α2 is increased, a value corresponding to time is shown as shown in the following equation (26). It can also be used.

[Equation 26]
Deceleration command value α2
= Deceleration according to Equation 10 just before reaching the release speed
-D4 × Elapsed time t from when the release speed is reached
However, D4 is a constant.

  In this way, according to the seventh and eighth embodiments, even if the host vehicle exceeds the control region, it depends on the detected vehicle distance and the relative speed immediately before exceeding the control region, depending on the vehicle speed or time. Since the braking force or deceleration is adjusted, in addition to the effects of the fifth and sixth embodiments, the braking force or deceleration is adjusted appropriately according to the relative relationship with the preceding vehicle when the control range is exceeded. The effect which can be done is produced.

  Next, an inter-vehicle distance control apparatus according to a ninth embodiment of the present invention will be described with reference to FIGS. The ninth embodiment is characterized in that an alarm unit 27 is additionally provided in addition to the braking force adjustment unit 26 with respect to the seventh embodiment shown in FIG. This alarm unit 27 is for notifying the driver that the speed control region has been exceeded by sound from the speaker or LED display when receiving a determination output from the speed control region determination unit 23 that the speed control region has been exceeded. . All other components are common to the seventh embodiment shown in FIG. 16 and function in the same manner.

  In the case of the ninth embodiment, the operation is the same as that of the seventh embodiment shown in FIG. 16, but as shown in the flowchart of FIG. 22, the operation of the seventh embodiment is shown in FIG. In addition to the braking force command value output in step S18e by the braking force adjustment unit 26, an alarm output by the alarm unit 27 in step S18g is added to the flowchart. That is, when the speed control region determination unit 23 determines that the speed control region is exceeded in step S17a, the braking force adjustment unit 26 determines the vehicle speed or time according to the inter-vehicle distance da and the relative speed vb immediately before exceeding the control region. Accordingly, the braking force Ft1 (= Ft) is adjusted to be relaxed, held or increased, and Ft2 obtained as a result of the adjustment is given to the driving force control unit 16 (step S18e). The driver is informed by an alarm sound or a display output informing that it has been exceeded (step S18g). Then, the throttle opening and the brake fluid pressure are controlled to adjust the braking force (steps S19 and S29).

  Thus, in the case of the ninth embodiment, even if the host vehicle speed exceeds the speed control region, the braking force is applied according to the vehicle speed or time according to the detected inter-vehicle distance and the relative speed immediately before exceeding the control region. In addition to the effects of the seventh embodiment, it is possible to adjust and notify the driver by warning. It can be released.

  The alarm unit 27 in the ninth embodiment employs a means for causing the driver to detect a light shock by suddenly changing the braking force in place of or together with the alarm sound or the alarm display means. You can also That is, as shown in FIGS. 23 (a) and 23 (b), when the host vehicle speed va becomes the release speed, the braking force command value Ft output by the inter-vehicle distance control unit 15 is set to 0 or returned to the original. The brake fluid pressure ba (see (c) in the figure) that responds temporarily is varied several times between 0 and the original value, causing a slight shock to the vehicle and setting the control area for the driver. It is perceived that the inter-vehicle distance control is canceled due to exceeding.

  In the ninth embodiment, the alarm unit 27 is additionally provided to the seventh embodiment shown in FIG. 16, but instead, the eighth embodiment shown in FIG. The alarm unit 27 may be additionally provided together with the speed adjustment unit 26a with respect to the embodiment. Also in this case, as the alarm unit 27, as in the ninth embodiment, a warning sound or warning display means is employed, or a means for performing an operation of temporarily changing the deceleration is employed. . In this case, an alarm output step is added after step S18f to the flowchart of the eighth embodiment shown in FIG.

  According to the ninth embodiment, even if the vehicle speed exceeds the speed control region, the braking force or the time depends on the vehicle speed or time according to the detected inter-vehicle distance and the relative speed immediately before exceeding the control region. Deceleration can be adjusted and the driver can be informed by an alarm. In addition to the effects of the seventh and eighth embodiments, the driver is notified when shifting to braking force adjustment or deceleration adjustment in the low speed range. It is possible to cancel the inter-vehicle distance control early by informing the vehicle.

  The alarm unit 27 employed in the ninth embodiment includes the braking force relaxation releasing unit 21 shown in FIG. 1, the deceleration relaxation releasing unit 21a shown in FIG. 6, and the braking force relaxation releasing unit shown in FIG. 21, the deceleration relaxation release unit 21 a in FIG. 10, the braking force holding unit 25 in FIG. 12, or the deceleration holding unit 24 in FIG. 14, thereby enabling the driver to release the inter-vehicle distance control. Will be able to recognize it early.

  Next, an inter-vehicle distance control apparatus according to a tenth embodiment of the present invention will be described with reference to FIGS. The feature of the tenth embodiment is that the braking force adjusting unit 26 is omitted from the seventh embodiment shown in FIG. 16 and an alarm unit 27 is provided instead. As in the ninth embodiment, when the alarm unit 27 receives a determination output indicating that the speed control region has been exceeded from the speed control region determination unit 23, the alarm unit 27 uses a speaker sound or LED display, or shown in FIG. This is to inform the driver that the speed control range has been exceeded. All other components are common to the seventh embodiment shown in FIG. 16 and function in the same manner.

  In the case of the tenth embodiment, in the normal inter-vehicle distance control, the inter-vehicle distance da is detected, the relative speed vb is calculated, and the own vehicle speed is calculated, as in the processing of the third embodiment shown in FIG. va is detected, and the target inter-vehicle distance db is calculated and applied to the inter-vehicle distance control unit 15 (steps S11 to S14), and the inter-vehicle distance control unit 15 calculates the braking / driving force Ft and supplies it to the driving force control unit 16 ( Step S15).

  Then, the speed control release determination unit 23 compares the vehicle speed detection value va with the release speed vd. If the vehicle speed detection value va is larger than the release speed, the inter-vehicle distance control is continued and the vehicle speed detection value va becomes less than the release speed. For example, a control release command is output to the inter-vehicle distance control unit 15 and the alarm unit 27 (step S17a).

  When the speed control release determining unit 23 determines to continue the inter-vehicle distance control in step S17a, the braking force adjusting unit 26 does not intervene in the braking / driving force Ft output from the inter-vehicle distance control unit 15 as in the third embodiment. Then, each of the throttle actuator 17 and the brake actuator 18 is operated so as to coincide with the throttle opening sa calculated by the driving force control unit 16 and the brake hydraulic pressure ba to adjust the own vehicle speed, and the own vehicle is the target with respect to the preceding vehicle. Control is performed so as to follow while maintaining the inter-vehicle distance db (steps S19 and S20).

  On the other hand, when the speed control cancellation determination unit 23 determines that the control is canceled in step S17a, the inter-vehicle distance control unit 15 stops the inter-vehicle distance control, and the alarm unit 27 that receives the control cancellation command simultaneously issues an alarm. Output to inform the driver (steps S17b, S17c).

  As described above, according to the tenth embodiment, when the vehicle speed exceeds the speed control region, the driver can be notified by an alarm sound, a display, or a slight shock.

  As in the tenth embodiment, it is possible to omit the deceleration adjustment unit 26a in the eighth embodiment shown in FIG. 19 and provide only the alarm unit 27 instead. The same effects as in the tenth embodiment are achieved.

  Next, an inter-vehicle distance control apparatus according to an eleventh embodiment of the present invention will be described with reference to FIGS. The inter-vehicle distance control device according to the eleventh embodiment includes an inter-vehicle distance detection unit 11, a vehicle speed detection unit 12, a driving force control unit 16, a throttle actuator 17 and a brake actuator similar to those in the first embodiment shown in FIG. 18 is provided.

  The inter-vehicle distance control apparatus according to this embodiment is further characterized by calculating the braking / driving force Ft necessary for controlling the actual inter-vehicle distance to the target inter-vehicle distance according to the inter-vehicle distance da and the relative speed vb. A distance control unit 15, a preceding vehicle speed calculation unit 30 that calculates the speed ve of the preceding vehicle from the relative speed vb from the relative speed calculation unit 13 and the host vehicle speed va from the vehicle speed detection unit 12; A control area over prediction unit 31 that compares the set control release speed vd of the host vehicle to predict whether or not the host vehicle will exceed the release speed vd, and an alarm sound or alarm according to the control area over prediction result And an alarm unit 32 for outputting a display.

  Next, the operation of the eleventh embodiment will be described with reference to the flowchart of FIG. The inter-vehicle distance detection unit 11 detects the inter-vehicle distance da with the preceding vehicle, the relative speed calculation unit 13 calculates the relative speed vb, the vehicle speed detection unit 12 detects the host vehicle speed va, and the vehicle speed da, the vehicle speed va, The relative speed vb is input to the inter-vehicle distance control unit 15 (steps S21 to S23).

  Then, an appropriate inter-vehicle distance with respect to the host vehicle speed va, that is, the target inter-vehicle distance db is calculated by the equation (1), and the braking / driving force Ft is calculated by the equation (2) from the relative speed vb, the inter-vehicle distance da, and the target inter-vehicle distance db. To the driving force control unit 16. Similar to the first embodiment, the driving force control unit 16 calculates the throttle opening sa and the brake hydraulic pressure ba based on the control characteristics shown in FIGS. 3 and 4 according to the applied braking / driving force Ft. The throttle opening sa and the brake hydraulic pressure ba are given to the throttle actuator 17 and the brake actuator 18, respectively, and the throttle opening 17 so that the throttle actuator 17 and the brake actuator 18 coincide with the command values given. The brake fluid pressure is activated (step S25).

  The preceding vehicle speed calculation unit 30 calculates the preceding vehicle speed ve by the following equation (27) and inputs it to the control region over prediction unit 31 (step S26).

[Equation 27]
Prior vehicle speed ve = own vehicle speed va + relative speed vb
The control region over predicting unit 31 compares the preceding vehicle speed ve with a preset control release speed vd (step S27).

  If it is determined in step S27 that the preceding vehicle speed ve is larger, the following vehicle speed va should also be higher than the control release speed vd, so the control is not released and the inter-vehicle distance control is continued. On the contrary, if the preceding vehicle speed ve is equal to or lower than the control release speed vd, it is predicted that the vehicle speed va following the vehicle speed va will immediately decrease below the control release speed vd. 32, the alarm unit 32 outputs an alarm (step S28).

Thus, according to the eleventh embodiment, when the preceding vehicle speed ve exceeds the speed control region vd, a warning is given that the vehicle may also exceed the speed control region.
(1) If the control is not canceled during deceleration control as in the conventional example, it is difficult to perform automatic deceleration control based on the inter-vehicle distance at low speeds, but the driver is warned early and the inter-vehicle distance control is stopped. Can be
(2) When the configuration is such that the control is canceled when the following inter-vehicle distance is exceeded, there is a possibility that if the control is automatically canceled during deceleration, the vehicle may be too close to the preceding vehicle. By doing so, you can make an approach avoidance approach early,
(3) Even when it is configured to gradually cancel the control when the control region is exceeded as in the first to eighth embodiments, the driver can be warned and the inter-vehicle distance control can be stopped early. .

  In the eleventh embodiment shown in FIG. 26, the braking / driving force Ft is calculated by the inter-vehicle distance control unit 15, and the throttle opening sa corresponding to the braking / driving force Ft and the brake hydraulic pressure are calculated by the driving force control unit 16. The inter-vehicle distance control device that calculates the throttle opening and brake fluid pressure by calculating ba has been described. However, the target vehicle speed vc is calculated by the inter-vehicle distance control unit 15a as in the second, fourth, and sixth embodiments. In contrast to this, for the circuit configuration in which the vehicle speed control unit 15b calculates the braking / driving force Ft and inputs the braking / driving force Ft to the driving force control unit 16, the preceding vehicle speed calculation unit 30 is similar to the eleventh embodiment. By providing the control region over prediction unit 31 and the warning unit 32, it is possible to configure an inter-vehicle distance control device having the same function and effect.

  Next, a twelfth embodiment of the present invention will be described with reference to FIGS. The inter-vehicle distance control device according to the twelfth embodiment includes an inter-vehicle distance detection unit 11, a vehicle speed detection unit 12, an inter-vehicle distance control unit 15, a driving force control unit 16, a throttle actuator 17, and the like as in the eleventh embodiment. A brake actuator 18 is provided, and a preceding vehicle speed calculation unit 30 is further provided.

  The inter-vehicle distance control device of this embodiment is further characterized as a feature of the present invention, a deceleration detection unit 34 for detecting deceleration according to the brake hydraulic pressure ba output from the driving force control unit 16, a brake until control release, An alarm that outputs an alarm based on the judgment result of the approach prediction unit 35 to the preceding vehicle that predicts whether or not the preceding vehicle is too close by the deceleration by the engine brake after the release of control, and the approach prediction unit 35 to the preceding vehicle A portion 36 is provided.

  Next, the operation of the twelfth embodiment having the above configuration will be described with reference to the flowchart of FIG. As in the eleventh embodiment, the inter-vehicle distance detection unit 11 detects the inter-vehicle distance da with the preceding vehicle, the relative speed calculation unit 13 calculates the relative speed vb, and the vehicle speed detection unit 12 detects the host vehicle speed va. The vehicle speed da, the vehicle speed va, and the relative speed vb are input to the inter-vehicle distance control unit 15 (steps S31 to S33). The inter-vehicle distance control unit 15 calculates the braking / driving force Ft and applies the braking / driving force Ft to the driving force control unit 16, and the driving force control unit 16 calculates the throttle opening sa and the brake fluid pressure ba according to the applied braking / driving force Ft. Then, the throttle actuator 17 and the brake actuator 18 actuate the throttle opening and the brake hydraulic pressure so as to coincide with the given command values (step S35).

  Similar to the eleventh embodiment, the preceding vehicle speed calculation unit 30 calculates the preceding vehicle speed ve by the above-described equation 27 and inputs it to the approaching prediction unit 35 for the preceding vehicle (step S36). Further, the deceleration detection unit 34 receives the brake fluid pressure command value ba output from the driving force control unit 16 and obtains the deceleration β1 corresponding to the brake fluid pressure command value ba from the following equation 28 to the preceding vehicle. To the approach prediction unit 35 (step S37).

[Equation 28]
Brake deceleration β1 = E1 × brake hydraulic pressure ba + E2
However, E1 and E2 are constants and are values obtained by linearly approximating experimental values as shown in FIG. In addition, the calculation of the deceleration β1 of the own vehicle is not limited to the above method, and the own vehicle speed va can be calculated by time differentiation or by time difference.

  The approach predicting unit 35 for the preceding vehicle selects the deceleration β2 due to engine braking after the release of control (step S38), and then the preceding vehicle speed ve from the preceding vehicle speed calculating unit 30 and the deceleration detecting unit 34 are selected. Based on the brake deceleration β1 until the control is released, the deceleration β2 due to the engine brake after the control is released, and the preset release speed vd, the approach distance is calculated by the following equation (29) (step S39).

[Equation 29]
Approach distance dc = inter-vehicle distance detection value da
-(Vehicle speed va-Release speed vd) ² / (2 x Brake deceleration β1)
-(Release speed vd-preceding vehicle speed ve) ² / (2 x engine brake deceleration β2)
Then, the obtained approach distance dc is compared with a predetermined value, and if the approach distance dc is smaller than the predetermined value, the alarm unit 36 outputs an approach warning to the preceding vehicle and notifies the driver (steps S40 and S41). ).

  As a result, according to the twelfth embodiment, it is predicted whether or not the preceding vehicle will be approached too much due to the deceleration by the brake until the control is released and the engine brake after the control is released. By outputting, the effects (1) to (3) are obtained as in the eleventh embodiment.

  In the twelfth embodiment shown in FIG. 28, the braking / driving force Ft is calculated by the inter-vehicle distance control unit 15, and the throttle opening sa corresponding to the braking / driving force Ft and the brake fluid are calculated by the driving force control unit 16. Although the inter-vehicle distance control device that calculates the pressure ba and adjusts the throttle opening and the brake hydraulic pressure has been described, the inter-vehicle distance control unit 15a sets the target vehicle speed vc as in the second, fourth, and sixth embodiments. For the circuit configuration in which the vehicle speed control unit 15b calculates the braking / driving force Ft and inputs the braking / driving force Ft to the driving force control unit 16, the preceding vehicle speed calculation unit 30 and the deceleration detection unit are similar to the above. 34. By providing the approach prediction unit 35 and the warning unit 36 for the preceding vehicle, it is possible to configure an inter-vehicle distance control device having the same function and effect.

  Next, an inter-vehicle distance control apparatus according to a thirteenth embodiment of the present invention will be described with reference to FIGS. The inter-vehicle distance control device according to the thirteenth embodiment includes an inter-vehicle distance detection unit 11, a vehicle speed detection unit 12, an inter-vehicle distance control unit 15, a driving force control unit 16, a throttle actuator 17, and a brake similar to those in the twelfth embodiment. An actuator 18 is provided, and a deceleration detector 34 is provided.

  The inter-vehicle distance control device according to this embodiment is further characterized in that as a feature of the present invention, it is determined whether or not the control range is exceeded from the own vehicle speed va from the vehicle speed detection unit 12 and the deceleration β1 from the deceleration detection unit 34. A region over prediction unit 37 and a warning unit 38 that outputs a warning when it is determined that the control region is over are provided.

  Next, the operation of the thirteenth embodiment having the above configuration will be described with reference to the flowchart of FIG. Similar to the twelfth embodiment, the inter-vehicle distance da with the preceding vehicle is detected, the relative speed vb with respect to the preceding vehicle is calculated, the own vehicle speed va is detected, and these are input to the inter-vehicle distance control unit 15 (step) S51-S53).

  The inter-vehicle distance control unit 15 calculates the braking / driving force Ft and applies the braking / driving force Ft to the driving force control unit 16, and the driving force control unit 16 calculates the throttle opening sa and the brake fluid pressure ba according to the applied braking / driving force Ft. Then, the throttle actuator 17 and the brake actuator 18 actuate the throttle opening and the brake hydraulic pressure so as to coincide with the given command values (step S55).

  As in the twelfth embodiment, the deceleration detection unit 34 obtains the deceleration β1 by Equation 28 and inputs it to the control region over prediction unit 37 (step S56).

  The control region over prediction unit 37 predicts and calculates the time from the own vehicle speed va and the deceleration β1 from the deceleration detection unit 34 until the control release speed is exceeded, using Equation 30 (step S57).

[Equation 30]
Control region overestimated predicted time
= (Own vehicle speed va-release speed vd) / deceleration β1
If the predicted time T is shorter than a predetermined value, the alarm unit 38 outputs an alarm to notify the driver (steps S58 and S59).

  Note that the calculation of the deceleration of the host vehicle is not limited to the above method, and the host vehicle speed va can be time-differentiated or calculated by a time difference, and is not particularly limited.

  Thus, according to the thirteenth embodiment, whether or not the control region is exceeded is predicted according to the own vehicle speed va and the deceleration β1, and an alarm is output when it is predicted that the control region will be exceeded. Therefore, the effects (1) to (3) are obtained as in the eleventh embodiment.

The block diagram which shows the structure of the 1st Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The internal circuit figure of the driving force control part in said embodiment. The engine map which a driving force control part utilizes in said embodiment. Explanatory drawing which shows the sensing area of the inter-vehicle distance detection part in said embodiment. The block diagram which shows the structure of the 2nd Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 3rd Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 4th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 5th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 6th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 7th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The graph which shows the braking force characteristic by said embodiment. The flowchart which shows the structure of the 8th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 9th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The timing chart which shows the operating characteristic of said embodiment. The flowchart which shows the structure of the 10th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 11th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows the structure of the 12th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The graph of the brake hydraulic pressure-deceleration characteristic employ | adopted by said embodiment. The flowchart which shows the structure of the 13th Embodiment of this invention. The flowchart which shows operation | movement of said embodiment. The flowchart which shows operation | movement of a prior art example. Explanatory drawing of the detection characteristic of a common inter-vehicle distance detection apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Inter-vehicle distance detection part 12 Vehicle speed detection part 13 Relative speed calculation part 14 Target inter-vehicle distance calculation part 15 Inter-vehicle distance control part 15a Inter-vehicle distance control part 15b Vehicle speed control part 16 Driving force control part 17 Throttle actuator 18 Brake actuator 19 Lane width detection part DESCRIPTION OF SYMBOLS 20 Sensing possibility judgment part 21 Braking force relaxation release part 21a Deceleration relaxation release part 22 Release speed setting part 23 Speed control area judgment part 25 Braking force holding part 25a Deceleration holding part 26 Braking force adjustment part 26a Deceleration adjustment part 27 Warning section 30 Preceding vehicle speed detection section 31 Control region over prediction section 32 Warning section 34 Deceleration detection section 35 Approach prediction section for preceding vehicle 36 Warning section 37 Control area over prediction section 38 Warning section

Claims (2)

An inter-vehicle distance detecting means for detecting an inter-vehicle distance between the host vehicle and the preceding vehicle;
A relative speed detecting means for detecting a relative speed with the preceding vehicle;
Own vehicle speed detecting means for detecting the vehicle speed of the own vehicle;
The inter-vehicle distance control that controls the braking / driving force according to the detected inter-vehicle distance and the relative speed to control the actual inter-vehicle distance to the target inter-vehicle distance, and cancels the control when the own vehicle speed is equal to or lower than a predetermined control release speed. Means,
Deceleration detection means for detecting the deceleration of the vehicle;
During the inter-vehicle distance control by the inter-vehicle distance control means, the deceleration until the control release detected by the deceleration detection means , the preset deceleration after the control release, and the inter-vehicle distance detected by the inter- vehicle distance detection means distance detection value and the relative speed detected by said relative speed detecting means, the vehicle speed detection based on the vehicle speed detected by means, the vehicle speed is pre-Symbol vehicle becomes less than the control release rate and approaching prediction means for predicting prior control cancel that approaches within a predetermined distance to the preceding vehicle by releasing the distance control,
An inter-vehicle distance control device comprising alarm means for outputting an alarm when approaching a preceding vehicle within a predetermined distance by canceling the inter-vehicle distance control. 2. The inter-vehicle distance control device according to claim 1 , wherein the warning means gives a sudden change in braking / driving force to generate a shock that can be perceived by the driver.

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