JP5706698B2 - Auto reducer for automobile - Google Patents

Description

  The present invention relates to an automatic deceleration device for an automobile that automatically applies a braking force to a host vehicle independent of a driver's operation of a brake pedal.

Patent Document 1, the vehicle has the technology according to the automatic train control for stopping at the target position is disclosed, manner of control, a pre-final stop target position than for example 2 [m] hand the goal, speed predetermined value, the target to alter placed the final target stop position when it is for example 10 [km / h] or less. It is disclosed that the control command change is reduced by this control, and deterioration of the riding comfort of the vehicle is suppressed (page 4, left lower column, lines 8 to 13 of Patent Document 1).

JP-A-3-117306

  By the way, in the train braking technique according to Patent Document 1, it is assumed that accurate position information is obtained from a ground element fixed at a specific point.

  On the other hand, in an automobile that performs automatic deceleration control based on position information of a navigation device or the like, the target position itself set based on the navigation device or the like deviates from the actual target position due to an error of the navigation device or the like. There is a problem of end.

  In addition, the train braking technique according to Patent Document 1 is basically intended to stop accurately at the target position, and for this purpose, correction to increase or decrease the notch by ± 1 is allowed. There is a possibility that acceleration will increase, and in this case, the ride comfort will be worse.

  Furthermore, as described above, the train braking technique according to Patent Document 1 is intended to stop accurately at a target position, and, for example, a control that reduces to a legal speed at a target position as in an automobile. Is not considered and there is room for improvement.

  The present invention has been made in consideration of such various problems, and it is possible to reduce the speed error with respect to the target speed at the actual target position (actual target position), as well as to the driver and the like. It is an object of the present invention to provide an automatic deceleration device for an automobile that makes it possible to obtain a deceleration pattern with little discomfort given to the vehicle.

The automatic deceleration device for automobiles according to this invention is
In an automatic deceleration device for an automobile that automatically gives a braking force to the host vehicle independent of the operation of the driver's brake pedal,
A position detection unit that detects the position of the host vehicle based on information of a satellite positioning device ;
Based on the position of the host vehicle detected by the position detection unit, when the position to be the recommended speed is estimated ahead of the travel path, the position to be the recommended speed is automatically or manually determined by the host vehicle. A target position setting unit for setting the target position to reach
A target speed setting unit which sets the recommended speed of the vehicle at the target position to the target speed,
When the speed of the host vehicle is larger than the set target speed, a deceleration control unit that decelerates the host vehicle by the automatic braking force and controls the speed so as to be the target speed at the target position; And have the following features (1) to ( 7 ).

(1) The deceleration control unit
Based on the position of the host vehicle detected by the position detector, the host vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, The first reference deceleration is maintained up to a predetermined second remaining distance position where the remaining distance is shorter than the first remaining distance position , and the deceleration at the second remaining distance position is lower than the first reference deceleration. Switching to a small second reference deceleration stepwise , controlling to travel to the target position while maintaining the second reference deceleration , and controlling to achieve the target speed at the target position ; and The predetermined second remaining distance is set longer as the position detection accuracy of the position detection unit that detects the position of the host vehicle becomes lower.

  With this configuration, even if the target position set by the target position setting unit has an error from the actual target position (actual target position), the distance required for deceleration by the first reference deceleration before approaching the target position While the time can be shortened, since the vehicle decelerates at the second reference deceleration with a small deceleration in the vicinity of the target position, an error with respect to the target speed at the actual target position can be reduced.

  In addition, since the vehicle gradually decelerates at the first deceleration having a relatively large deceleration before approaching the target position, and decelerates at the second deceleration having a relatively small deceleration near the target position. The driver can know that the target speed has been approached sensuously from the decrease in deceleration. The deceleration pattern is less uncomfortable for the driver.

Furthermore, since the automatic deceleration section can be shortened compared to the control in which the entire section is automatically decelerated at the second reference deceleration with a small deceleration, the degree of freedom of the driver's maneuvering operation is increased up to the automatic deceleration control section. can do.
Furthermore, by setting the predetermined second remaining distance longer as the position detection accuracy becomes lower, the error of the target speed at the target position is equivalent to that when the position detection accuracy is high. can do.

  The target position may be set automatically by the target position setting means or manually by an operator such as a driver.

(2) In the invention having the feature (1),
The deceleration control unit
In order to control to achieve the target speed at the target position, the speed in the constant speed traveling, the first reference deceleration, and the second reference deceleration smaller than the first reference deceleration When controlling the vehicle with a pattern,
Setting the speed pattern
First, the host vehicle is set to travel to the second reference deceleration that is smaller than the first reference deceleration at the predetermined second remaining distance position before the target position,
Next, a speed at the second remaining distance position is calculated based on the second remaining distance, the second reference deceleration, and the target speed,
Further, based on the calculated speed, the current speed, the second remaining distance, and the first reference deceleration, the remaining distance from the second remaining distance that switches from the constant speed travel to the first reference deceleration travel. The first remaining distance having a long length is determined.

  With this configuration, the second remaining distance position to be switched to the second reference deceleration, which is smaller than the first reference deceleration, is determined in advance, and the speed at the second remaining distance position is further calculated. The speed control setting can be specifically executed.

( 3 ) In the invention having the feature ( 1 ) or ( 2 ),
The deceleration control unit
The number may be determined to be low detection accuracy of the smaller position of the satellite at which the position of the vehicle by the satellite positioning device of the position detecting unit has been detected.

( 4 ) In the invention having the feature ( 1 ) or ( 2 ),
The deceleration control unit
Furthermore, when using a map matching unit that corrects the position of the host vehicle by comparing the position of the satellite positioning device with a road map for each predetermined unit of travel distance, the position is not corrected by the map matching unit The position detection accuracy is determined to be low.

  In this case, when the map matching is performed, the shift of the current position with respect to the road map is reduced. Therefore, the entire section in which the automatic deceleration is performed by the above control can be shortened to ensure the driver's operability.

( 5 ) In the invention having any one of the features (1) to (4),
The deceleration control unit
The vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, and a second predetermined distance shorter than the first remaining distance position. By controlling so that the first reference deceleration gradually decreases and travels at the second reference deceleration in the section before and after the remaining distance position, and at the target position to control the target speed, Shock due to a change in deceleration near the target position can be reduced.

( 6 ) In the invention having any one of the features (1) to (4),
The deceleration control unit
Control is performed so that the host vehicle travels at a first reference deceleration by gradually increasing deceleration from constant speed traveling in a section before and after the first remaining distance position before the target position. Control is performed so that the vehicle travels at the second reference deceleration by gradually decreasing the first reference deceleration in a section before and after the predetermined second remaining distance position where the remaining distance is shorter than the distance position, and at the target position. By controlling so as to achieve the target speed, the deceleration distance can be shortened even when the vehicle speed is high, and the shock due to the change in deceleration can be reduced.
(7) The deceleration control unit
Based on the position of the host vehicle detected by the position detector, the host vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, The first reference deceleration is maintained up to a predetermined second remaining distance position where the remaining distance is shorter than the first remaining distance position, and the deceleration at the second remaining distance position is lower than the first reference deceleration. Switching to a small second reference deceleration stepwise, controlling to travel to the target position while maintaining the second reference deceleration, and controlling to achieve the target speed at the target position; and The second reference deceleration is decreased and the first reference deceleration is increased as the position detection accuracy of the position detection unit that detects the position of the host vehicle is lowered.
With this configuration, as the position detection accuracy is lowered, the second reference deceleration is reduced, and the first reference deceleration is set larger, thereby reducing the error in the target speed at the target position. This can be equivalent to when the position detection accuracy by the position detection unit is high.

  According to the present invention, it is possible to reduce the speed error with respect to the target speed at the actual target position (actual target position), and it is possible to set a deceleration pattern with little uncomfortable feeling given to the driver.

It is a block diagram of the automatic deceleration device for automobiles concerning one embodiment of this invention. This is an explanation of the correspondence between the remaining distance to the target position and the speed / deceleration. It is a flowchart with which description of the process by the automatic brake control part which carries out deceleration control so that it may become target speed in a target position is provided. It is explanatory drawing which shows the setting characteristic of the speed and deceleration with respect to the remaining distance to the target position which concerns on embodiment. 4 is a flowchart showing details of speed characteristic setting processing in FIG. 3. FIG. 6A is an explanatory diagram of a correspondence relationship between the remaining distance to the target position and the speed / deceleration according to the first embodiment. FIG. 6B is an explanatory diagram of a correspondence relationship between the remaining distance to the target position and the speed according to the first embodiment. FIG. 7A is an explanatory diagram of a correspondence relationship between the remaining distance to the target position and the speed / deceleration according to the second embodiment. FIG. 7B is an explanatory diagram of a correspondence relationship between the remaining distance to the target position and the speed according to the second embodiment. It is explanatory drawing of the correspondence of the remaining distance to the target position and speed and deceleration which concern on 3rd Example. It is explanatory drawing of the correspondence of the remaining distance to the target position and speed and deceleration which concern on 4th Example.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram of an automatic deceleration device 10 for an automobile according to this embodiment. The automatic deceleration device 10 for an automobile is mounted on a vehicle (also referred to as a host vehicle) 11 such as a four-wheel passenger car, and basically includes an accelerator pedal 12, an operation amount sensor 14 (accelerator pedal operation amount sensor), and a vehicle speed. A sensor 16 (vehicle speed meter), an automatic brake mechanism 18, a navigation device 20, an ECU (Electronic Control Unit) 22, a reaction force applying mechanism 24, a vehicle speed control mechanism 26, and a brake pedal 28 are provided. Prepare.

  The accelerator pedal operation amount sensor 14 detects an operation amount (accelerator pedal operation amount θ [°]) from the original position (θ = 0 [°]) of the accelerator pedal 12 by using a potentiometer or the like, and outputs it to the ECU 22.

  The vehicle speed sensor 16 measures the vehicle speed (current speed) v [km / h] of the vehicle and outputs it to the ECU 22.

  The automatic brake mechanism 18 includes a hydraulic control mechanism 18A and a brake actuator 18B. The brake actuator 18B is constituted by a disc brake or the like that generates braking force on four wheels (not shown), and each braking force (braking oil pressure) of the brake actuator 18B is provided by four pressure regulators in the hydraulic control mechanism 18A. (Not shown), respectively.

  The hydraulic control mechanism 18A generates a braking hydraulic pressure corresponding to the depression amount of the brake pedal 28, and outputs a braking force command value that does not depend on the driver's operation of the brake pedal 28, which is output from the automatic brake control unit 22B constituting the ECU 22. Accordingly, the brake hydraulic pressure is generated and output to the brake actuator 18B.

  As shown in FIG. 2, in this embodiment, the automatic brake control unit 22 </ b> B has a first remaining distance position P <b> 1 (remaining distance x is a first distance) that the vehicle 11 is closer to the target position P <b> 0 (system output target position). The remaining distance x1) is controlled so that the vehicle travels from the constant reference speed (current speed vc) to the first reference deceleration (first deceleration) a1, and the remaining distance x from the first remaining distance position P1 (x = x1). The second reference deceleration (second deceleration) a2 (a2 <a2 <a) that is smaller than the first reference deceleration a1 at the predetermined second remaining distance position P2 (the remaining distance x is the second remaining distance x2). The vehicle is controlled to travel at a1), and the speed v and deceleration a of the host vehicle 11 are controlled through the automatic brake mechanism 18 so that the target speed Vt (vt ≧ 0) is achieved at the target position P0.

  In FIG. 2, the target position P0 is the system output target position P0 set by the target speed / position setting unit 22D. The target position P0 is a position error (in FIG. , The position is shifted according to the remaining distance x3). In this embodiment, the position error is dominated by the error due to the navigation device 20.

  The navigation device 20 can detect the position of the vehicle by using a GPS (Global Positioning System) which is a satellite positioning device, and stores a road map and information of a recommended speed Vs [km / h] of each road. 30. The navigation device 20 includes a display unit 20 </ b> A that displays the position of the host vehicle 11 on a road map, an input unit 20 </ b> B (also functions as a target position setting unit) configured by a touch panel and the like, and the navigation device 20. A map matching unit 20C for correcting the position of the host vehicle 11 on the display unit 20A to a middle position on a nearby road with reference to the road map with respect to the detected position is provided.

  Here, the recommended speed Vs indicates, for example, the speed at which the fuel consumption can be optimized according to the situation of each road, that is, the so-called cruise speed, as well as the speed limit of each road. The speed at which the fuel consumption can be optimized can be set in advance depending on the fuel consumption performance characteristics of the vehicle, the road gradient, the road type (asphalt, gravel road, etc.), the presence or absence of a curve, and the like.

  The recommended speed Vs is not only the fuel efficiency optimization speed or the road speed limit described above, but also distance information with a preceding vehicle that can be detected by a radar device (not shown), wiper operation and raindrop sensor information, and past information on each road. Accident history, actual driving speed of the road (the driving speed of the road is taken up by an external information center from the vehicle equipped with the navigation device, and the information center calculates the actual driving speed), road environment (suburbs, urban areas, residential areas) , Or school zone, etc.), the road speed / number of lanes, road markings detected by image processing, road surface μ, etc.

  The reaction force control unit 22 </ b> A of the ECU 22 calculates a reaction force Fr to be applied to the accelerator pedal 12 using the recommended speed Vs and the current speed (current speed) vc and the like to generate a control signal, and through the reaction force applying mechanism 24. A reaction force Fr is applied to the accelerator pedal 12.

  The reaction force applying mechanism 24 is composed of a motor (not shown) connected to the accelerator pedal 12 and applies a reaction force Fr corresponding to a control signal received from the ECU 22 to the accelerator pedal 12.

  As a result, the accelerator pedal 12 is moved to the original position of the accelerator pedal 12 itself by a spring or the like (when the foot is released from the accelerator pedal 12 by the force to return to the original position, the accelerator pedal 12 operates the accelerator pedal. In addition, the reaction force Fr from the reaction force applying mechanism 24 is added.

  The vehicle speed control mechanism 26 includes a transmission system in addition to a throttle valve whose opening degree is controlled by so-called drive-by-wire control based on the accelerator pedal operation amount θ.

  The ECU 22 operates as a function realization unit (function realization means) that realizes various functions by executing a program stored in a memory (storage unit) 23 such as a ROM based on various inputs. In this embodiment, the ECU 22 functions as a reaction force control unit 22A, an automatic brake control unit 22B, a recommended speed estimation unit 22C, a target speed / position setting unit 22D, and the like. The memory 23 includes a flash memory, an EEPROM, a RAM, a hard disk and the like in addition to the ROM.

  The automobile automatic speed reduction device 10 according to this embodiment is basically configured and operates as described above. Next, the vehicle speed control mechanism 26 and the automatic brake mechanism 18 are used to cruise at a constant speed. The processing by the automatic brake control unit 22B that performs deceleration control so that the host vehicle 11 (running at a constant speed) reaches the target speed vt at the target position P0 will be described in detail with reference to the flowchart of FIG.

  In step S1, the automatic brake control unit 22B recommends a recommended speed at which the vehicle speed (current speed) vc needs to be reduced forward within a predetermined distance range on the travel path through a recommended speed estimation unit 22C that monitors the output of the navigation device 20. It is detected whether or not Vs is estimated.

  When the recommended speed Vs has been estimated, in step S2, the target speed / position setting unit 22D sets the position to be the recommended speed Vs to the target position P0 (remaining distance x = 0) and also sets the target position P0. The recommended speed Vs is set to the target speed vt (vt = Vs).

  The target position P0 and the target speed vt at the target position P0 are automatically set by the automatic brake control unit 22B, but can be manually set by the driver or the like using the input unit 20B.

  Next, in step S3, it is determined whether or not the current speed vc is higher than the target speed vt.

  When the current speed vc is higher than the target speed vt, in other words, when the target speed vt is lower than the current speed vc, in step S4, the automatic brake control unit 22B sets the vehicle speed control mechanism 26 and the automatic brake mechanism. A speed characteristic 54 referred to by 18 is set.

  Although the method of setting the speed characteristic 54 will be described later, FIG. 4 shows the speed characteristic 54 as a setting result.

  This speed characteristic 54 is obtained from the constant speed travel section 64 from the current position Pc (remaining distance xp) to the first remaining distance position P1 (first remaining distance x1), and from the first remaining distance position P1 (first remaining distance x1). The first deceleration zone 71 traveling at the first reference deceleration a1 up to the second remaining distance position P2 (second remaining distance x2), and the system output target position P0 from the second remaining distance position P2 (second remaining distance x2). This is a speed / deceleration characteristic in the second deceleration section 72 that travels at the second reference deceleration a2 up to (remaining distance 0).

  This speed characteristic 54 indicates the distance / time required for deceleration by the relatively large first reference deceleration a1 before approaching the target position P0 even if the system output target position P0 has an error from the actual target position Pr. In the vicinity of the target position P0, the vehicle is decelerated at the second reference deceleration a2 having a relatively small deceleration, and an error (speed error) Δv (Δvj <Δvk) with respect to the target speed vt at the actual target position Pr is as much as possible. Set to be smaller.

  FIG. 5 is a detailed flowchart for setting the speed characteristic 54 in step S4.

  First, in step S4a, from the target position P0 of the second remaining distance position P2 (deceleration switching position) for switching from the first deceleration a1 in the first deceleration section 71 to the second deceleration a2 in the second deceleration section 72. The second remaining distance x2 is set (calculated).

  This second remaining distance x2 is determined in advance as an appropriate value for the current speed vc, the distance from the current position Pc to the system output target position P0, the road surface condition, the traveling condition such as the weather, and the vehicle type (memory). 23, which is stored in advance as a second remaining distance setting characteristic or setting map), and is usually a value of about 100 [m] or less.

Next, in step S4b, the speed vs (deceleration switching position speed) at the second remaining distance position P2 is calculated from the equation (formula) of the equal acceleration linear motion of the following equation (1).
vs ² −vt ² = 2 × x2 × a2 (1)

  In the equation (1), the target speed vt, the second remaining distance x2 (the remaining distance x at the target position P0 is set to x = 0), and the second deceleration a2 are known. vs can be calculated.

Next, in step S4c, the first remaining distance x1 at the first remaining distance position P1, which is the switching position from the constant speed traveling section 64 to the first deceleration section 71, is represented by the following constant acceleration linear motion of the following equation (2). It is calculated from the formula (formula).
vc ² −vs ² = 2 × | x1−x2 | × a1 (2)

  Here, since the current speed vc, the deceleration switching position speed vs, the second remaining distance x2, and the first deceleration a1 are known, the first remaining distance x1 can be calculated.

  In this manner, in step S4, the speed characteristic 54 shown in FIG. 4 (the current speed vc, which is a constant speed at the first remaining distance position P1, is switched from the first speed a1 to the first deceleration a1, and the first decrease at the second remaining distance position P2 is obtained. The speed a1 is switched to the second deceleration a2, and the characteristic that the speed v at the target position P0 becomes the target speed vt) is set. At the same time, the deceleration characteristic 154 shown in FIG. 4 is set.

  Next, in step S5, the automatic brake control unit 22B refers to the current position from the navigation device 20 and the vehicle speed v from the vehicle speed sensor 16 based on the set speed characteristic 54 and deceleration characteristic 154 (as an argument), By controlling the vehicle speed control mechanism 26 and the automatic brake mechanism 18, deceleration control along the speed characteristic 54 shown by the solid line in FIG. 4 is performed.

  That is, in the speed characteristic 54, the remaining distance xp to the first remaining distance x1 is the constant speed traveling section 64 at the current speed vc, and the second remaining distance position from the first remaining distance position P1 (first remaining distance x1). The first deceleration section 71 at the first deceleration a1 with a large deceleration up to P2 (second remaining distance x2) is set, and the system output target position P0 (remaining distance) from the second remaining distance position P2 (second remaining distance x2). The second deceleration zone 72 at the second deceleration a2 with a small deceleration until x = 0).

As described above, according to the above-described embodiment, the automobile automatic speed reduction device 10 that automatically applies to the host vehicle 11 a braking force that does not depend on the driver's operation of the brake pedal 28 is provided at the position of the host vehicle 11. A target speed / position setting unit 22D as a target position setting unit for setting a target position P0 for reaching the host vehicle 11 by the automatic braking force, and a target position P0. When the target speed / position setting unit 22D as a target speed setting unit for setting the target speed vt of the host vehicle 11 at this time and the current speed vc of the host vehicle 11 is larger than the set target speed vt, the host vehicle 11 is decelerated. is allowed, with an automatic brake control section 22B of the deceleration control unit for deceleration control the speed v so that the target speed vt at the target position P0, the.

  In this embodiment, the automatic brake control unit 22B controls the host vehicle 11 to travel from the constant speed travel to the first reference deceleration a1 at the first remaining distance position P1 before the target position P0. Control is performed so that the vehicle travels at a second reference deceleration a2 that is smaller than the first reference deceleration a1 at a predetermined second remaining distance position x2 that is shorter than the remaining distance position P1, and the target position P0. Thus, the target speed vt is controlled.

  According to this configuration, even if the target position P0 set by the target speed / position setting unit 22D has an error with respect to the actual target position (actual target position) Pr, the relative position before the target position P0 approaches the target position P0. The distance and time required for deceleration can be shortened by the large first reference deceleration a1, while the vehicle travels at the second reference deceleration a2 where the deceleration is small near the target position P0, so the target speed vt at the actual target position Pr The error with respect to can be reduced.

  The effect will be described in comparison with the comparative example. In the speed characteristic 52 indicated by a one-dot chain line as a comparative example having only one deceleration characteristic in the deceleration section, the remaining distance xp to the remaining distance xa are the current speed vc. The constant speed traveling section 62 is set, and the second deceleration a2 having a small deceleration from the position of the remaining distance xa to the target position P0 (remaining distance x = 0) is set. Further, in the speed characteristic 50 indicated by a two-dot chain line as another comparative example having only one deceleration characteristic in the deceleration section, the remaining distance xp to the remaining distance xb are defined as the constant speed traveling section 60 at the current speed vc. The first deceleration a1 having a large deceleration from the position of the remaining distance xb to the target position P0 (remaining distance x = 0).

  The speed error Δv at the actual target position P0 can make the speed error Δvj due to the speed characteristic 54 according to the embodiment smaller than the speed error Δvk due to the speed characteristic 50 according to the comparative example (Δvj <Δvk).

  The constant speed traveling section 64 according to the embodiment is longer than the constant speed traveling section 62 by the speed characteristic 52 according to the comparative example.

  In addition, according to this embodiment, the vehicle decelerates significantly before approaching the target position P0 in advance, and the deceleration is reduced in the vicinity of the target position P0, so that the driver knows that the target speed vt has been approached. It can be seen that this is a deceleration pattern with little discomfort given to the driver.

  At the position before the first remaining distance position P1 and the position before the second remaining distance position P2, the automatic brake control unit 22B of the ECU 22 speeds through the sound output using the display unit 20A and / or the speaker of the navigation device 20, respectively. It is preferable to notify that the vehicle travels at a constant speed at vc, the deceleration a becomes the first deceleration a1, and the deceleration a becomes the second deceleration a2.

  As described above, the automatic deceleration section is shortened (xa to 0 is set to x1 to 0) as compared with the control in the comparative example in which the entire deceleration section is automatically decelerated with the second reference deceleration a2 having a small deceleration. Therefore, the drivability of the driver can be improved. In practice, if the speed at the first remaining distance position P1 of the first remaining distance x1 is the speed vc, the distance between the remaining distance xp and the remaining distance x1 can travel at a free speed v. It is sufficient that the vehicle is in a constant speed traveling state at the speed vc immediately before the first remaining distance position P1.

  In the above-described embodiment, the automatic brake control unit 22B performs constant speed traveling at the current speed vc, decelerating traveling at the first reference deceleration a1, and control so as to achieve the target speed vt at the target position P0. When a speed pattern for deceleration traveling in the order of the second reference deceleration a2 that is smaller than the first reference deceleration a1 is set, and the speed pattern is set, a predetermined second remaining before the host vehicle 11 is positioned before the target position P0. After setting to travel to the second reference deceleration a2 that is smaller than the first reference deceleration a1 at the distance position P2, the second remaining distance x2, the second reference deceleration a2, the target speed vt, Based on the above, the speed vs at the second remaining distance position P2 is calculated {see equation (1)}, and the calculated speed vs, the current speed vc, the second remaining distance x2, and the first reference deceleration a1. And from the constant speed running It switched to reference deceleration traveling, to determine long the first remaining distance x1 of remaining distance x from the second remaining distance x2 {(2) see the equation}.

According to this configuration, defines a second remaining distance position P 2 for switching the first reference deceleration a1 second reference deceleration a2 smaller deceleration than previously, further speed vs at the second remaining distance position P 2 By calculating, the deceleration control setting can be specifically executed.

  Briefly describing the operational effects of the above-described embodiment, the deceleration error a is set to a small second deceleration a2 near the target position P0, and the speed error Δv at the actual target position Pr is reduced. On the other hand, before approaching the target position P0, the deceleration a is set to a large deceleration a1, and the distance required for deceleration is shortened. That is, at first, the vehicle is decelerated at a large deceleration a1 toward the target speed vt at the target position P0, and is decreased toward the target position P0 to reduce the speed error Δv at the actual target position Pr. be able to.

  When the automatic braking is applied, the point where the target speed vt is reached varies due to the position detection error in the navigation device 20, and therefore, the low G corresponding to the second deceleration a2 (G. Meaning.) You can avoid feeling the error. Initially, the large G corresponding to the first deceleration a1 is weakened when approaching the target point, so that the uncomfortable feeling is reduced.

  In addition, when the target position P0 is set to the stop position (v = 0), it may stop before or behind the actual target position Pr (automatic brake control stops). Since there are few errors, the performance is practically sufficient.

[First embodiment]
In this first embodiment, as shown in FIGS. 6A and 6B, the automatic brake control unit 22B responds to detecting that the position detection accuracy by the navigation device 20 that detects the position of the host vehicle 11 is low. Thus, the predetermined second remaining distance x2 is set longer.

  When the position detection accuracy is low, the second remaining distance x2 is set to the near side as schematically shown by the double-sided arrow 100 extending in the lateral direction in FIG. 6A, and the equation (2) is set accordingly. Based on this, the first remaining distance x1 is set to the near side, as schematically shown by the double arrow 102 extending in the lateral direction. As a result, the constant speed travel section 64 is set to a shorter constant speed travel section 64f, and the speed characteristic 54 is changed to the speed characteristic 54a.

  On the other hand, when the position detection accuracy is high, the second remaining distance x2 is set to the back side, and the first remaining distance x1 is set to the back side based on the equation (2) according to this (constant speed). The travel section 64 is set to a longer constant speed travel section 64b.) The constant speed travel section 64 is changed to the constant speed travel section 64b, and the speed characteristic 54 is changed to the speed characteristic 54b.

  In accordance with the accuracy of the navigation device 20, the predetermined second remaining distance x2 is set longer as the position detection accuracy becomes lower, so that the error Δvj of the target speed vt at the target position P0 is determined as the position detection accuracy. Can be equivalent to when it is high.

[Second Embodiment]
In the second embodiment, as shown in FIGS. 7A and 7B, the automatic brake control unit 22B is configured in accordance with the fact that the position detection accuracy by the navigation device 20 that detects the position of the host vehicle 11 decreases. The reference deceleration a2 may be reduced and the first reference deceleration a1 may be set larger.

  7A, when the position detection accuracy is low, the first deceleration a1 of the characteristic 50 is changed to the first deceleration a1 ′ side of the characteristic 50 ′. The second deceleration a2 of the characteristic 52 is decreased toward the characteristic 52 ″ second deceleration a2 ″ (FIG. 7B). When the position detection accuracy is high, the first deceleration a1 of the characteristic 50 is reduced to the first deceleration a1 ″ side (FIG. 7B) of the characteristic 50 ″, and the second deceleration a2 of the characteristic 52 is The second deceleration a2 ′ (FIG. 7B) on the 52 ′ side (FIG. 7B) is increased.

  As described above, as the detection accuracy of the position detected by the navigation device 20 is lowered, the second reference deceleration a2 is reduced and the first reference deceleration a1 is set larger, so that the position at the target position P0 is increased. The error of the target speed vt can be made equal to that when the position detection accuracy is high.

  In addition, when performing the position detection using the navigation device 20 that performs the satellite positioning device, it can be determined that the detection accuracy is lower as the number of satellites when the position is calculated is smaller.

  In the first embodiment and the second embodiment described above, the automatic brake control unit 22B is configured such that the navigation device 20 that detects the position of the host vehicle 11 has a satellite positioning device and a satellite positioning device for each predetermined unit of travel distance. Since the map matching unit 20C that corrects the position of the host vehicle 11 by comparing the position of the vehicle with the road map is used, it is detected whether the map matching process is employed, and the map matching process is performed. If this is the case, the difference between the current position and the road map becomes small, so the entire section (sections x1 to 0) where automatic deceleration is performed by the above control is made shorter to ensure the driver's operability. Can do.

  When the position detection unit that detects the position of the host vehicle 11 is only the satellite positioning device, it can be determined that the position detection accuracy is lower as the number of satellites when the position is detected is smaller.

[Third embodiment]
In the third embodiment, as shown in FIG. 8, the automatic brake control unit 22B operates at a constant speed (v = vc, a = 0) when the host vehicle 11 is at the first remaining distance position P1 before the target position P0. ) To travel at the first reference deceleration a1, and the section before and after the predetermined second remaining distance position x2 shorter than the first remaining distance position P1 (the remaining distance xc to xd section). The first reference deceleration a1 is gradually reduced to control the vehicle so that the vehicle travels at the second reference deceleration a2, and at the target position P0, the target speed vt is controlled. A shock due to a change in the deceleration a in the vicinity of a certain second remaining distance position P2 (change from the first reference deceleration a1 to the second reference deceleration a2) can be reduced.

[Fourth embodiment]
In the fourth embodiment, as shown in FIG. 9, the automatic brake control unit 22B determines that the vehicle speed v = vc ′ (a = 0) according to the size of the vehicle speed v at the time of entering the deceleration control. ), As indicated by the speed characteristic 54c and the deceleration characteristic 154c, the host vehicle 11 gradually increases the deceleration a from the first remaining distance position x1 'before the target position P0, starting from a = 0. controlled so as to run at the reference deceleration a1 ', the first remaining distance position P1 than the remaining distance x short predetermined second remaining distance position P from the position of the remaining distance xc in front of the 2 first reference deceleration a1 ′ Is gradually decreased to control the vehicle to travel from the remaining distance xd at the second reference deceleration a2, and at the target position P0, the target speed vt is controlled so that the vehicle speed v becomes v = vc ′ . also it is possible to shorten the deceleration distance is greater than vc, and reduced It is possible to reduce the shock due to the change of time.

Further, when the host vehicle speed v = vc ″ ( vc < vc ″ <vc ′, a = 0), the host vehicle 11 is in front of the target position P0 as indicated by the speed characteristics 54b and the deceleration characteristics 154b. Control is performed such that the deceleration a is increased from a = 0 from the first remaining distance position x1 ″ and the vehicle travels at the first reference deceleration a1 ″, and the remaining distance x is shorter than the first remaining distance position P1. The first reference deceleration a1 ″ is gradually decreased from the position of the remaining distance xc before the second remaining distance position Ps to control the vehicle so that the vehicle travels from the remaining distance xd at the second reference deceleration a2. by controlling so that the target speed vt at position P0, the vehicle speed v is v = vc '' and vc 'can also be shortened deceleration distance is smaller than, and reduces shock due to deceleration of change be able to.

  Note that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

10 ... Automatic deceleration device for automobiles 11 ... Vehicle (own vehicle)
16 ... Vehicle speed sensor 18 ... Automatic brake mechanism 20 ... Navigation device 22 ... ECU
a ... deceleration a1 ... first reference deceleration a2 ... second reference deceleration P0 ... target position (system output target position) P1 ... first remaining distance position P2 ... second remaining distance position Pc ... current position Pr ... actual target Position v ... Vehicle speed (speed)
vc ... current speed v ... target speed x ... remaining distance x1 ... first remaining distance x2 ... second remaining distance

Claims (7)

In an automatic deceleration device for an automobile that automatically gives a braking force to the host vehicle independent of the operation of the driver's brake pedal,
A position detection unit that detects the position of the host vehicle based on information of a satellite positioning device ;
Based on the position of the host vehicle detected by the position detection unit, when the position to be the recommended speed is estimated ahead of the travel path, the position to be the recommended speed is automatically or manually determined by the host vehicle. A target position setting unit for setting the target position to reach
A target speed setting unit which sets the recommended speed of the vehicle at the target position to the target speed,
When the speed of the host vehicle is larger than the set target speed, a deceleration control unit that decelerates the host vehicle by the automatic braking force and controls the speed so as to be the target speed at the target position; Have
The deceleration control unit
Based on the position of the host vehicle detected by the position detector, the host vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, The first reference deceleration is maintained up to a predetermined second remaining distance position where the remaining distance is shorter than the first remaining distance position , and the deceleration at the second remaining distance position is lower than the first reference deceleration. Switching to a small second reference deceleration stepwise , controlling to travel to the target position while maintaining the second reference deceleration , and controlling to achieve the target speed at the target position ; and The automatic decelerating device for an automobile , wherein the predetermined second remaining distance is set longer as the position detection accuracy of the position detection unit that detects the position of the host vehicle is lowered . In the automatic deceleration device for automobiles according to claim 1,
The deceleration control unit
In order to control to achieve the target speed at the target position, the speed in the constant speed traveling, the first reference deceleration, and the second reference deceleration smaller than the first reference deceleration When controlling the vehicle with a pattern,
Setting the speed pattern
First, the host vehicle is set to travel to the second reference deceleration that is smaller than the first reference deceleration at the predetermined second remaining distance position before the target position,
Next, a speed at the second remaining distance position is calculated based on the second remaining distance, the second reference deceleration, and the target speed,
Further, based on the calculated speed, the current speed, the second remaining distance, and the first reference deceleration, the remaining distance from the second remaining distance that switches from the constant speed travel to the first reference deceleration travel. An automatic decelerator for an automobile characterized by determining a long first remaining distance. In the automatic deceleration device for automobiles according to claim 1 or 2 ,
The deceleration control unit
Wherein the position detecting portion of the satellite positioning device by the automatic deceleration device for a motor vehicle, wherein the determining and the detection accuracy of the position as the number of satellites when the position of the vehicle is detected less is low. In the automatic deceleration device for automobiles according to claim 1 or 2 ,
The deceleration control unit
Furthermore, when using a map matching unit that corrects the position of the host vehicle by comparing the position of the satellite positioning device with a road map for each predetermined unit of travel distance, the position is not corrected by the map matching unit It is determined that the position detection accuracy is low. In the automatic reduction device for automobiles according to any one of claims 1 to 4,
The deceleration control unit
The vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, and a second predetermined distance shorter than the first remaining distance position. The first reference deceleration is gradually decreased in the section before and after the remaining distance position, and the vehicle is controlled to travel at the second reference deceleration, and the target speed is controlled at the target position. An automatic decelerator for automobiles. In the automatic reduction device for automobiles according to any one of claims 1 to 4,
The deceleration control unit
Control is performed so that the host vehicle travels at a first reference deceleration by gradually increasing deceleration from constant speed traveling in a section before and after the first remaining distance position before the target position. Control is performed so that the vehicle travels at the second reference deceleration by gradually decreasing the first reference deceleration in a section before and after the predetermined second remaining distance position where the remaining distance is shorter than the distance position, and at the target position. An automatic deceleration device for an automobile, which is controlled to achieve the target speed. In an automatic deceleration device for an automobile that automatically gives a braking force to the host vehicle independent of the operation of the driver's brake pedal,
A position detection unit that detects the position of the host vehicle based on information of a satellite positioning device;
Based on the position of the host vehicle detected by the position detection unit, when the position to be the recommended speed is estimated ahead of the travel path, the position to be the recommended speed is automatically or manually determined by the host vehicle. A target position setting unit for setting the target position to reach
A target speed setting unit for setting the recommended speed of the host vehicle at the target position as a target speed;
When the speed of the host vehicle is larger than the set target speed, a deceleration control unit that decelerates the host vehicle by the automatic braking force and controls the speed so as to be the target speed at the target position; Have
The deceleration control unit
Based on the position of the host vehicle detected by the position detector, the host vehicle is controlled to travel at a first reference deceleration from a constant speed travel at a first remaining distance position before the target position, The first reference deceleration is maintained up to a predetermined second remaining distance position where the remaining distance is shorter than the first remaining distance position, and the deceleration at the second remaining distance position is lower than the first reference deceleration. Switching to a small second reference deceleration stepwise, controlling to travel to the target position while maintaining the second reference deceleration, and controlling to achieve the target speed at the target position; and The second reference deceleration is decreased and the first reference deceleration is increased as the position detection accuracy of the position detection unit that detects the position of the host vehicle is lowered.
An automatic speed reducer for automobiles.

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