JP6363821B2 - Idle stop control device - Google Patents

Description

  The present invention relates to an idle stop control device that changes the operating state of an engine of a host vehicle between a driving state and a stopped state according to driving conditions.

  In recent years, in order to reduce fuel consumption and exhaust gas, vehicles such as automobiles automatically stop the engine when the vehicle stops due to traffic lights or traffic jams, and restart the engine when it is necessary to operate the engine. Various techniques for the so-called idle stop function have been proposed.

  For example, in Patent Document 1, if the inter-vehicle distance from the preceding vehicle is less than the set value, or the signal color emitted from the traffic light is red or yellow, and the speed of the host vehicle is 0 (zero), That is, idle stop is performed when the vehicle is waiting for a signal at an intersection or the like. And the technique of restarting an engine when the distance between vehicles becomes more than a setting value or the color of the traffic light has changed to blue is shown.

  Patent Document 2 discloses a technique for automatically stopping the engine when the speed of the host vehicle falls below a predetermined vehicle speed not only in a stopped state but also during deceleration traveling by a brake operation in order to realize further reduction in fuel consumption. Has been.

Japanese Patent Laid-Open No. 7-4284 JP 2002-173909 A

  By the way, if the idle stop time is short, not only the effect of reducing the fuel consumption is reduced, but also the fuel consumption may be deteriorated. Moreover, frequent repeated engine stop and restart not only deteriorates driving feeling and ride comfort, but also causes deterioration of the starter motor and ring gear and battery consumption. Therefore, when carrying out idle stop while driving, avoid situations where the driver depresses the accelerator pedal and re-accelerates after idle stop, that is, the situation where the engine is restarted before stopping after idle stop. There is a need. Therefore, in the technique of Patent Document 2 described above, the speed at which the engine is automatically stopped must be set to a low value such as 10 km / h, and the effect of reducing fuel consumption is limited.

  In view of such a problem, the present invention realizes an appropriate idling stop while driving after surely determining the driver's intention to stop in consideration of the surrounding environment of the host vehicle, and has an excellent fuel efficiency effect. An object of the present invention is to provide an idle stop control device that can be obtained.

In order to solve the above-described problems, an idle stop control device according to the present invention includes an engine control unit that controls an operation state of an engine of a host vehicle, and a course that determines whether or not the traveling state of the host vehicle is a coasting state. A signal determining unit, a signal color specifying unit for specifying a signal color emitted from a traffic light located in front of the host vehicle, a preceding vehicle specifying unit for specifying the state of the preceding vehicle, and a distance from the host vehicle to the traffic signal a distance specifying unit for a traveling band specifying unit that specifies the traveling band number in the running direction of the vehicle, provided with an engine control unit, the traveling state Ri coasting state that is traveling band number on one side of a two-lane Oh Rutoki, signal color is red or yellow, and, although the preceding vehicle is no or preceding vehicle is has stopped or decelerated, distance traveled by the vehicle to maintain a coasting state If longer than the distance to the traffic signal, characterized in that the engine is stopped.

In order to solve the above-described problem, another idle stop control device of the present invention determines an engine control unit that controls an operation state of an engine of the own vehicle and whether or not the running state of the own vehicle is a coasting state. A coasting determination unit, a signal color identifying unit that identifies a signal color emitted from a traffic light located in front of the host vehicle, a preceding vehicle identifying unit that identifies a state of the preceding vehicle, and a distance from the host vehicle to the traffic signal A distance between the vehicle's planned travel path and the planned travel path of the interrupted vehicle candidate that is a candidate for the interrupted vehicle, the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate, An interrupt prediction unit that predicts a vehicle interruption ahead of the host vehicle based on a change in the distance of the vehicle and an angle formed by the planned traveling track of the host vehicle and the planned driving track of the interrupting vehicle candidate; With an engine When it is predicted that the running state is a coasting state and the vehicle is not interrupted, the signal color is red or yellow, and there is no preceding vehicle or there is a preceding vehicle, but the vehicle stops or decelerates. The engine is stopped when the distance traveled by maintaining the coasting state of the host vehicle is longer than the distance to the traffic light.

In order to solve the above-described problem, another idle stop control device of the present invention determines an engine control unit that controls an operation state of an engine of the own vehicle and whether or not the running state of the own vehicle is a coasting state. A coasting determination unit, a level crossing specifying unit for specifying the state of a level crossing located in front of the host vehicle, a preceding vehicle specifying unit for specifying the state of the preceding vehicle, and a distance specifying unit for specifying the distance from the host vehicle to the level crossing And a traveling zone identifying unit that identifies the number of traveling zones in the traveling direction of the host vehicle , and the engine control unit has a railroad crossing when the traveling state is a coasting state and the number of traveling zones is one lane. When the vehicle is in a shut-off state and there is no preceding vehicle, or there is a preceding vehicle, but it has stopped or decelerated, and the distance traveled by maintaining the coasting state is longer than the distance to the railroad crossing Characterized in that to stop the engine.

In order to solve the above-described problem, another idle stop control device of the present invention determines an engine control unit that controls an operation state of an engine of the own vehicle and whether or not the running state of the own vehicle is a coasting state. A coasting determination unit, a level crossing specifying unit for specifying the state of a level crossing located in front of the host vehicle, a preceding vehicle specifying unit for specifying the state of the preceding vehicle, and a distance specifying unit for specifying the distance from the host vehicle to the level crossing And the change in the distance between the planned travel path of the own vehicle and the planned travel path of the interrupted vehicle candidate that is a candidate for the interrupt vehicle, the change in the distance between the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate, and An interrupt prediction unit that predicts an interruption of the vehicle ahead of the host vehicle based on one of the angles formed by the planned traveling track of the host vehicle and the scheduled driving track of the interrupt vehicle candidate ,
When the engine control unit predicts that the running state is the coasting state and the vehicle is not interrupted, the level crossing is in a cut-off state, and there is no preceding vehicle or there is a preceding vehicle, but it is stopped or decelerated. The engine is stopped when the distance traveled by maintaining the coasting state of the host vehicle is longer than the distance to the railroad crossing.

  According to the present invention, it is possible to realize an appropriate idle stop while traveling while reliably determining the driver's intention to stop in consideration of the surrounding environment of the host vehicle, and to obtain an excellent fuel saving effect. Become.

It is the functional block diagram which showed the schematic structure of the idle stop control apparatus. It is explanatory drawing for demonstrating a luminance image and a distance image. It is explanatory drawing for demonstrating operation | movement of the target object specific | specification part. It is explanatory drawing for demonstrating the interruption vehicle prediction process of an interruption prediction part. It is explanatory drawing for demonstrating the transition conditions to an engine stop state. It is the flowchart which showed the flow of the whole process of the idle stop control method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Vehicle system)
In a vehicle such as an automobile, power is obtained by a driving mechanism such as an engine, and steering or braking of the vehicle is executed by a driver's operation through a steering wheel or a brake pedal. Also, in recent years, the road environment ahead of the host vehicle is imaged by an outside environment recognition unit including an in-vehicle camera mounted on the vehicle, and an object such as a preceding vehicle is identified based on color information and position information in the image, Vehicles equipped with a so-called anti-collision function that avoids a collision with an identified object and keeps the distance between the preceding vehicle and the preceding vehicle at a safe distance (ACC: Adaptive Cruise Control) are becoming widespread. In addition, for the purpose of reducing fuel consumption and exhaust gas, it is equipped with a so-called idle stop function that automatically stops the engine when the vehicle stops due to traffic light or traffic jams, and restarts the engine when the engine needs to be operated. The number of vehicles is increasing. The functions of the vehicle itself such as the drive mechanism, steering, and braking are disclosed in various existing documents, for example, Japanese Patent Application Laid-Open No. 2012-116299 of the same applicant.

  However, in a vehicle equipped with such an idle stop function, if the idle stop time is short, the effect of reducing fuel consumption is reduced, and there is a risk that the fuel consumption will deteriorate. In addition, if the engine is stopped each time the vehicle speed falls below the predetermined vehicle speed without considering the surrounding environment, the starter motor and ring gear will deteriorate and the battery will be consumed due to frequent engine stop and restart. There is also a risk that the running performance is impaired.

  Therefore, in the present embodiment, the driver's intention to stop is appropriately grasped by considering the road environment in front of the host vehicle using the outside environment recognition unit in the above-described collision prevention function. Then, based on such a driver's intention to stop, an object is to realize an appropriate idle stop during traveling and to obtain an excellent fuel saving effect. Hereinafter, the idle stop control device 100 that realizes such an idle stop function will be described in detail.

(Idle stop control device 100)
FIG. 1 is a functional block diagram showing a schematic configuration of the idle stop control device 100. The idle stop control device 100 includes an I / F unit that performs one-way or two-way information exchange with other devices in the host vehicle 1, a RAM, a flash memory, an HDD, and the like. It is composed of a semiconductor integrated circuit including a data holding unit that holds various necessary information, a central processing unit (CPU), a ROM that stores programs, a RAM as a work area, and the like. And a central control unit for controlling. The central control unit functions as the vehicle exterior environment recognition unit 102, the input unit 104, and the control unit 106 in cooperation with the I / F unit and the data holding unit. Hereinafter, the vehicle environment recognition unit 102, the input unit 104, and the control unit 106 will be described.

(External vehicle environment recognition unit 102)
The vehicle exterior environment recognition unit 102 includes an image processing unit 120 and an object specifying unit 122, acquires image data obtained by capturing the road environment ahead of the host vehicle 1, and within the image based on the image data. An object such as a preceding vehicle is specified based on color information and position information. Here, the object is not only a three-dimensional object that exists independently such as a vehicle, a traffic light, a road (travel zone), a traffic sign, a guardrail, or a building, but also a three-dimensional object part such as a taillight, a blinker, or a lighting part of a traffic light. The thing which can be specified as is included. The outside environment recognition unit 102 is originally mounted on the vehicle in order to perform the collision prevention function.

  The image processing unit 120 continuously acquires image data obtained by imaging the road environment in the detection area in front of the host vehicle 1 from the imaging device 10 every frame (60 fps) for 1/60 seconds, for example, and updates the image data. As a trigger, image processing is performed. Here, the imaging device 10 includes, for example, two imaging devices such as a charge-coupled device (CCD) and a complementary metal-oxide semiconductor (CMOS), and the light of each of the two imaging devices on the traveling direction side of the host vehicle 1. They are spaced apart in a substantially horizontal direction so that the axes are substantially parallel. Further, the imaging device 10 can acquire the brightness of a color image, that is, three hues (red: R, green: G, blue: B) in units of pixels. Here, the color image picked up by the image pickup apparatus 10 is called a luminance image, and is distinguished from a distance image described later.

  FIG. 2 is an explanatory diagram for explaining the luminance image 210 and the distance image 212. When the image processing unit 120 acquires image data from each of the two imaging elements of the imaging device 10, the image processing unit 120 derives parallax (parallax information) using so-called pattern matching. Specifically, a block corresponding to a block arbitrarily extracted from the luminance image 210 based on one image data shown in FIG. 2A (for example, an array of 4 horizontal pixels × 4 vertical pixels) is used as the other image data. Search from the luminance image 210 based on. Here, the horizontal indicates the horizontal direction of the captured image, and the vertical indicates the vertical direction of the captured image. The image processing unit 120 associates the parallax information derived in this way (corresponding to a relative distance described later) with the image data, and generates a distance image 212 shown in FIG. Each block in such a distance image 212 is associated with the parallax of that block. Here, for convenience of explanation, in the distance image 212, blocks from which parallax is derived are represented by black dots.

  Returning to FIG. 1, the object specifying unit 122 acquires the luminance image 210 and the distance image 212 from the image processing unit 120, and obtains the luminance based on the luminance image 210 and the three-dimensional position information based on the distance image 212. It is used to specify which target object (pixel or block) in the detection region 214 corresponds to. At this time, the object specifying unit 122 converts the disparity information for each block in the detection area 214 in the distance image 212 into three-dimensional position information including a horizontal distance, a height, and a relative distance using a so-called stereo method. Convert. Here, the stereo method is a method of deriving a relative distance of the target object from the imaging device 10 from the parallax of the target object by using a triangulation method. At this time, the object specifying unit 122 determines the target part based on the relative distance of the target part and the detected distance on the distance image 212 between the point on the road surface and the target part at the same relative distance as the target part. Deriving the height from the road surface.

  Further, in the present embodiment, the object specifying unit 122 is configured such that the signal color specifying unit 130, the preceding vehicle specifying unit 132, the crossing specifying unit 134, the travel zone specifying unit 136, and the interrupt prediction unit according to the object to be specified. It functions as each functional unit such as 138. The signal color specifying unit 130 specifies signal colors (red, yellow, blue) emitted from a traffic light located in front of the host vehicle 1. The preceding vehicle specifying unit 132 specifies whether there is a preceding vehicle and whether the preceding vehicle is stopped or decelerated when there is a preceding vehicle. The level crossing identification unit 134 identifies the level crossing blocking state, that is, the level crossing warning light or the position of the blocking bar located in front of the host vehicle 1. The travel zone specifying unit 136 specifies the travel zones and the number thereof (the number of travel zones) with the white line or the side wall in the running direction of the host vehicle 1 as a boundary. The interrupt prediction unit 138 predicts an interrupt of the vehicle ahead of the host vehicle 1. Hereinafter, each functional unit of the object specifying unit 122 will be described in detail.

  FIG. 3 is an explanatory diagram for explaining the operation of the object specifying unit 122. Here, the identification procedure will be described by taking as an example the identification process of the red signal color of the traffic light by the signal color identification unit 130 among the functional units of the object identification unit 122. First, the signal color specifying unit 130 determines that the luminance of an arbitrary target part in the luminance image 210 is the luminance range of the target object (red signal color) (for example, the reference value is the luminance (R) and the luminance (G) is the reference value. Whether or not (R) is 0.5 times or less and luminance (B) is 0.38 times or less of reference value (R) is determined. And if it is contained in the brightness | luminance range used as object, the identification number which shows the said target object will be attached | subjected to the object site | part. Here, as shown in the enlarged view of FIG. 3, the identification number “1” is assigned to the target portion corresponding to the target (red signal color).

  Next, the signal color specifying unit 130 uses an arbitrary target part as a base point, and the difference between the target part and the horizontal distance and the height (may include a difference in relative distance) are within a predetermined range. The target parts that are considered to correspond to the same target object (with the same identification number) are grouped, and the target parts are also made an integrated target part group. Here, the predetermined range is represented by a distance in the real space, and can be set to an arbitrary value (for example, 1.0 m). Further, the signal color specifying unit 130 also applies to a target object (red signal) that has a difference in horizontal distance and a difference in height within a predetermined range with respect to the target part newly added by grouping. Group target parts with the same color). As a result, if the distances between the target parts with the same identification number are within a predetermined range, all the target parts are grouped. Here, as shown in the enlarged view of FIG. 3, the target part group 220 is formed by grouping the target parts with the identification number “1”.

  Subsequently, the signal color identification unit 130 determines that the grouped target part group 220 has a height range (for example, 4.5 to 7.0 m) and a width range (for example, 0.05 to 0.05) associated with the target object. 0.2 m), shape (for example, circular shape), etc., it is determined whether or not predetermined conditions are satisfied. Here, regarding the shape, the shape is compared with reference to a template associated with the object in advance (pattern matching), and it is determined that the condition is satisfied because there is a correlation greater than or equal to a predetermined value. If the predetermined condition is satisfied, the grouped target part group 220 is determined as a target (red signal color). In this example, the red signal color is specified as the object, but it goes without saying that the signal color specifying unit 130 can also specify the yellow signal color, the blue signal color, and the like.

  Moreover, when the target part group 220 has the characteristic peculiar to the target object, it may be determined as a target object on the condition. For example, when the light emitter of the traffic light is configured by an LED (Light Emitting Diode), the light emitter blinks at a cycle (for example, 100 Hz) that cannot be grasped by human eyes. Therefore, the signal color specifying unit 130 can also determine the object (red signal color) based on the change in the time direction of the luminance of the target portion of the luminance image 210 acquired asynchronously with the blinking timing of the LED.

  Similarly, the other functional units of the object specifying unit 122 can be specified in the same procedure using the luminance based on the luminance image 210 and the three-dimensional position information based on the distance image 212. For example, the preceding vehicle specifying unit 132 determines the preceding vehicle based on the shape, height, and size of the object located within a predetermined relative distance ahead of the host vehicle 1, the relative position of the tail lamp and the blinker on the object, and the like. Specify the presence or absence of. The level crossing specifying unit 134 specifies a warning light of a level crossing located in front of the host vehicle 1 based on its shape, height, and size, or based on a combination of a bar shape and a color (yellow and black). To identify the barrier and its posture. Based on the shape, size, and color, the travel zone identification unit 136 identifies the travel zones and the number of travel zones that are bounded by white lines, side walls, and the like in the travel direction of the vehicle 1.

  Further, the preceding vehicle specifying unit 132 further assigns a different ID to each vehicle traveling in the same direction as the host vehicle 1 among the vehicles in the road environment ahead of the host vehicle 1. Then, each vehicle is tracked by the ID. Next, the preceding vehicle specifying unit 132 refers to the travel zone specified by the travel zone specifying unit 136. For example, when the vehicle is in the same travel zone as the own vehicle 1, the relative speed and absolute acceleration of the vehicle are calculated. To derive. A vehicle having a relative speed within a predetermined range (for example, −10 to 10 km / h) in the same travel zone is set as a preceding vehicle. Here, the relative speed is obtained by dividing the relative distance from the preceding vehicle by unit time, and the absolute acceleration is obtained by dividing the absolute speed obtained by adding the speed of the host vehicle 1 to the relative speed by unit time. it can.

  As a means for deriving the absolute acceleration / deceleration (absolute acceleration) of the preceding vehicle, various existing techniques, for example, a technique such as Japanese Patent Application Laid-Open No. 2012-206700 of the same applicant can be used.

  Further, in the above, the preceding vehicle specifying unit 132 tracks the preceding vehicle or the like according to the traveling zone specified by the traveling zone specifying unit 136. However, when a so-called navigation unit is mounted on the own vehicle 1, such a navigation unit is provided. Each process may be performed according to the travel zone. The navigation unit obtains the absolute position of the vehicle 1 including latitude, longitude, and the like from a GPS receiving unit (not shown) via the I / F unit, and also includes a speed sensor 14 and a gyro sensor (not shown). The relative position from the reference position is obtained by, for example, and the position of the host vehicle 1 on the map is derived by the combination. Further, the navigation unit holds map data. Based on the map data and the position of the host vehicle 1 on the map, the road on which the host vehicle 1 is traveling and its travel zone (if there are a plurality of maps). Which of the plurality of traveling zones is determined).

  In addition, when there is a vehicle in a traveling zone different from the own vehicle 1, the interrupt predicting unit 138 predicts an interruption of the vehicle ahead of the own vehicle 1.

  FIG. 4 is an explanatory diagram for explaining the interrupt vehicle prediction process of the interrupt prediction unit 138. In FIG. 4A, there is a preceding vehicle 232 in the same traveling zone 230 as the host vehicle 1, and vehicles 236a and 236b are in other traveling zones 234 in the same direction. For example, the interrupt prediction unit 138 performs interrupt prediction for the vehicles 236a and 236b in the other traveling zones 234 in the same direction among the vehicles specified by the preceding vehicle specifying unit 132.

First, the interrupt predicting unit 138 follows the traveling locus of the host vehicle 1, the relative distance L ₁ between the far end of the vehicles 236 a and 236 b and the host vehicle 1, the preceding vehicle 232 (front end) and the host vehicle. comparing the relative distance L ₂ between 1. Vehicle 236a by such comparison, if the relative distance L ₁ between the distal end of 236b is shorter than the relative distance L ₂ between the preceding vehicle 232 and the vehicle and the candidate of the interrupt vehicle. This is because when the far end of the vehicles 236a and 236b in the other traveling zone 234 is in front of the preceding vehicle 232, the vehicles 236a in the other traveling zones 234 between the preceding vehicle 232 and the host vehicle 1 This is because 236b can interrupt. Therefore, here, only the vehicle 236b in FIG. 4A is a candidate for an interrupted vehicle.

Then, the interrupt prediction unit 138 predicts whether or not the candidate for the interrupting vehicle interrupts in front of the host vehicle 1. For example, the interrupt prediction unit 138 includes a distance L ₃ between the planned travel path of the host vehicle 1 and the planned travel path of the vehicle 236b that is a candidate for the interrupted vehicle, and the planned travel path of the host vehicle 1 and the vehicle that is the candidate for the interrupted vehicle. change in the distance L ₃ between the planned travel locus of 236b, self planned travel locus of the vehicle 1 and the scheduled travel path of the vehicle 236b is interrupt vehicle candidates is the angle theta _1, etc., the vehicle 236b actually interrupt It is determined whether the vehicle is an interrupting vehicle. For example, as shown in FIG. 4 (b), the distance L ₃ between the planned travel path of the vehicle 236b is planned travel path and interrupts the vehicle candidate of the own vehicle 1 or equal to or less than a predetermined threshold value, the traveling schedule of the vehicle 1 or approaching with the passage distance L ₃ is a time with the scheduled travel path of the vehicle 236b is locus and interrupt vehicle candidate, and the planned travel path of the vehicle 236b is planned travel path and interrupts the vehicle candidate vehicle 1 If the absolute value of the angle theta ₁ formed by a predetermined angle or more, the vehicle 236b is approaching the intended travel path of the vehicle 1, i.e., it can be determined that the interrupt vehicle.

  The interrupted vehicle prediction process can use various existing techniques, for example, techniques such as JP 2008-117073 of the same applicant.

(Input unit 104)
Returning to FIG. 1, the input unit 104 includes an accelerator deriving unit 150, a speed deriving unit 152, a road surface gradient deriving unit 154, and a coasting determining unit 156.

  The accelerator deriving unit 150 acquires the amount of depression of the host vehicle 1 on the accelerator pedal 12 and derives the operation amount of the driver to the accelerator pedal 12. The speed deriving unit 152 acquires the detection signal of the speed sensor 14 and derives the speed of the host vehicle 1. The road surface gradient deriving unit 154 acquires the detection signal of the gradient detection sensor 16 and derives the road surface gradient of the road surface on which the host vehicle is traveling.

  The coasting determination unit 156 determines whether or not the operation amount of the accelerator pedal 12 is equal to or less than a predetermined threshold (for example, an operation amount 0 or a value that is low enough to be regarded as the operation amount 0), that is, whether or not the accelerator pedal 12 is released. To do. As a result, if the operation amount of the accelerator pedal 12 is equal to or less than a predetermined threshold value, the host vehicle 1 is traveling with inertia regardless of the speed of the host vehicle 1 or the opening degree of the brake pedal. Set to coasting state.

(Control unit 106)
The control unit 106 includes an engine control unit 160. The engine control unit 160 changes the operating state of the engine 18 of the host vehicle 1 in accordance with a predetermined driving condition. For example, the engine control unit 160 changes the operation state of the engine 18 to the stop state when the predetermined engine automatic stop condition is satisfied in the operation state of the engine 18 (including the drive state and the idle state), and then the engine 18 When the restart condition is satisfied, the operation state is changed. Here, the operating state is a state in which the engine 18 is operated. Of these, the driving state refers to operating the engine 18 with a load applied. In the idle state, the throttle valve is fully closed and no operation is performed. It means that the engine 18 is operated in a load state. The stop state is a state in which the engine 18 is automatically stopped by cutting off the energization of the ignition circuit of the engine 18. When the operating state of the engine 18 transitions from the stopped state to the operating state, the engine 18 is restarted by energizing the starter and the engine ignition circuit as in the case of starting the engine 18.

  In the present embodiment, when the running state is the coasting state, the engine control unit 160 determines that the signal color specified by the signal color specifying unit 130 is red or yellow, and the preceding vehicle specifying unit 132 indicates that the preceding vehicle is When it is determined that there is no vehicle, or there is a preceding vehicle but it is determined that the preceding vehicle is stopped or decelerated (absolute acceleration is less than 0), the operating state of the engine 18 is changed from the driving state to the stopped state.

  In such a coasting state, if the signal color in front of the host vehicle 1 is red or yellow, the possibility of stopping the host vehicle 1 is increased, and the necessity of driving the engine 18 is decreased, but there is a preceding vehicle. In this case, the driving state (acceleration / deceleration) of the host vehicle may be affected by the driving state (acceleration / deceleration) of the preceding vehicle. Accordingly, if the preceding vehicle is accelerating even if the signal color ahead of the host vehicle 1 is red or yellow, the idle stop is not executed, and if the preceding vehicle is not present, or if the preceding vehicle is present, the vehicle is stopped or decelerated. The engine control unit 160 changes the operating state of the engine 18 to the stopped state only when the vehicle is stopped, that is, when the possibility of stopping the host vehicle 1 is extremely high. In this way, it is possible to start the engine 18 at an earlier timing than when the operating state of the engine 18 is changed to the stopped state at a lower speed as in the conventional technique, and the idle stop time can be increased accordingly. And an excellent fuel saving effect can be obtained. In the present embodiment, the running engine 18 can be automatically stopped at an earlier timing than before, but the idle stop is performed after the driver's intention to stop is surely determined in consideration of the surrounding environment of the host vehicle. Since it is implemented, it is possible to avoid a situation where the engine is restarted after the idling stop and before stopping.

  Further, the engine control unit 160 is not only in the signal color but also in the coasting state, the crossing warning light specified by the crossing specifying unit 134 is in a blinking state, or the posture of the crossing bar is in the blocking state, and When there is no preceding vehicle or there is a preceding vehicle but the vehicle is stopped or decelerated, the operating state of the engine 18 is changed from the driving state to the stopped state.

  If the warning light at the level crossing in front of the host vehicle 1 is lit in the coasting state, or if the barrier is in the blocking state, the possibility of stopping the host vehicle 1 increases and the engine 18 is driven. Since the necessity is low, the engine control unit 160 shifts the operation state of the engine 18 to the stop state. In this way, the stop of the engine 18 can be started earlier, and a reduction in fuel consumption can be expected.

  As described above, by grasping the state of the traffic light, the railroad crossing, and the preceding vehicle, it is possible to accelerate the stop of the engine 18 when changing to the stopped state, and to reduce the fuel consumption. However, when the idle stop function is executed, for example, when a CVT (Continuously Variable Transmission) is used as a transmission, the engine 18 cannot be stopped in an environment in which sudden braking occurs to ensure CVT reliability. There is a case. Therefore, in the present embodiment, the idle stop function is performed only under a situation where no sudden braking occurs.

  For example, when the traveling zone specifying unit 136 identifies the number of traveling zones in the traveling direction of the host vehicle 1, if the number of traveling zones is plural, the engine control unit 160 changes the engine 18 to the stop state. Ban. If the number of travel zones is plural, another vehicle may interrupt from a travel zone different from the travel zone in which the host vehicle 1 is traveling. Here, if there are a plurality of traveling zones, the transition to the stop state is prohibited, so that the idle stop function is not executed and the reliability of CVT can be ensured even if a sudden braking occurs.

  In addition, when the interrupt prediction unit 138 predicts a vehicle interruption ahead of the host vehicle 1, the engine control unit 160 prohibits the engine 18 from transitioning to a stopped state. In the present embodiment, as described above, the interruption of the vehicle can be predicted. If the vehicle has interrupted the front of the host vehicle 1, it must be braked suddenly. Here, when the interruption of the vehicle is predicted, by prohibiting the transition to the stop state, the idle stop function is not executed, and the reliability of the CVT can be ensured even if a sudden braking occurs.

  Further, if the idle stop function is performed even in a situation where engine braking is necessary, the engine braking effect cannot be obtained and the braking distance may be increased. Therefore, in this embodiment, the idle stop function is not executed under a situation where engine braking is required.

  For example, when the road surface gradient derived by the road surface gradient deriving unit 154 is equal to or greater than a predetermined threshold, that is, it is determined that the road surface is downhill in the traveling direction based on the derived road surface gradient (the road surface gradient is downhill) The engine control unit 160 prohibits the transition to the stop state. In this way, it is possible to prevent the idling stop function from being executed unintentionally in a situation where engine braking is required on a downhill, and the engine braking effect can be appropriately received.

  And the engine control part 160 performs drive control of the engine 18 according to the transition of an operation state. For example, if the operating state of the engine 18 is in the operating state, the engine 18 is operated, and if it is in the stopped state, the energization of the ignition circuit of the engine 18 is cut off and the engine 18 is automatically stopped. However, when the transition to the stop state of the engine 18 is prohibited, the engine 18 is not automatically stopped.

(Idle stop timing)
Hereinafter, the transition condition from the driving state to the stop state and the transition (return) condition from the stop state to the driving state when the host vehicle 1 is coasting and stopping will be described in detail. Basically, the operating state transitions at the time of coasting and at the time of stopping, respectively, but when the host vehicle 1 stops after transitioning to the stopping state at the time of coasting, the operation state at the time of coasting is changed to It is determined not by the transition condition but by the transition condition to the operation state at the time of stop.

(Conditions for transition to the stopped state during coasting)
As described above, in the coasting state, the engine control unit 160 is in a state where the signal color specified by the signal color specifying unit 130 is red or yellow and the warning light for the crossing specified by the crossing specifying unit 134 is blinking. Alternatively, when the position of the barrier is in the cutoff state and the preceding vehicle specifying unit 132 determines that there is no preceding vehicle, or there is a preceding vehicle but the preceding vehicle is stopped or decelerated. Next, the operating state of the engine 18 is changed from the operating state to the stopped state. Further, at this time, the conditions include that the number of traveling zones is one lane on one side, no interruption of the vehicle, and the traveling path is not a downhill with a predetermined inclination angle or more.

  Moreover, you may permit the transition to the stop state of the engine 18 by the relationship with the position (traffic stop position) of a traffic light or a preceding vehicle.

  FIG. 5 is an explanatory diagram for explaining a condition for transition of the engine 18 to the stop state. It is desirable for the own vehicle 1 to maintain the coasting and reach the position of the traffic light and the rear of the preceding vehicle 232 only by the braking process, but it does not reach the position of the traffic light and the rear of the preceding vehicle 232 only by maintaining the coasting. In some cases, it is necessary to restart the engine 18 by the operation of the accelerator pedal 12 or the function of following the preceding vehicle 232 using ACC.

In the present embodiment, the distance L ₄ traveled by maintaining the coasting when the vehicle reaches the position of the traffic light or behind the preceding vehicle 232 by maintaining the coasting, that is, as shown in FIG. longer than the distance L ₅ to the stop position of the vehicle relative to but traffic, and, when the relative velocity V ₁ of the if there is a preceding vehicle 232 and the own vehicle 1 and the preceding vehicle 232 is higher than the speed V ₂ which is expected to collide Allow transition to stop state.

  Thus, only maintaining the coasting does not lead to the position of the traffic light or the rear of the preceding vehicle 232, but it is necessary to restart the engine 18 by the operation of the accelerator pedal 12 or the function of following the preceding vehicle 232 using ACC. In this case, since the transition to the stopped state is prohibited, it is possible to quickly shift to a state where the engine 18 is loaded.

However, more specifically, the following conditions are also included, and the engine control unit 160 changes the operating state of the engine 18 from the operating state to the stopped state only when all of the following conditions are satisfied.
(1) The shift lever position is set to any one of “D”, “3rd speed”, “2nd speed”, “1st speed”, and “N”.
(2) The battery voltage is equal to or higher than a set threshold value.
(3) The water temperature of the engine 18 is equal to or higher than the threshold value.
(4) The booster negative pressure is not less than a predetermined value (brake negative pressure).
In addition, various conditions such as an idle stop switch and a steering angle condition can be taken into consideration.

(Conditions for transition (return) to operating state during coasting)
At the time of coasting, the engine control unit 160 releases the stop state and transitions to the operation state by satisfying any of the following conditions.
(1) The operation amount of the accelerator pedal 12 becomes a predetermined value or more (depresses).
(2) The transition (edge) from depression of the brake pedal to release (release) was detected.
(3) The signal color of the traffic light changed from red to blue.
(4) The level crossing warning light is turned off, or the blocking state of the blocking bar is released.
(5) A sudden brake was applied.
(6) The number of travel zones has become one side multiple lanes.
(7) There was a vehicle interruption.
(8) The traveling road is a downhill with a predetermined inclination angle or more.

(Conditions for transitioning to the stopped state when stopped)
When stopping, the engine control unit 160 transitions to the stopped state by satisfying all of the following conditions.
(1) The speed of the host vehicle 1 becomes a predetermined value or less (stops).
(2) The operation amount of the brake pedal becomes equal to or greater than a predetermined value (depressed).
(3) The transition (edge) from depression to release (release) of the accelerator pedal 12 was detected.
(4) The shift lever position is set to any one of “P”, “D”, “3rd speed”, “2nd speed”, “1st speed”, and “N”.
(5) The battery voltage is greater than or equal to the set threshold value.
(6) The water temperature of the engine 18 is equal to or higher than the threshold value.

(Conditions (returns) to the operating state when stopped)
When stopping, the engine control unit 160 cancels the stopped state and transitions to the operating state by satisfying any of the following conditions.
(1) The operation amount of the accelerator pedal 12 becomes a predetermined value or more (depresses).
(2) The transition (edge) from depression of the brake pedal to release (release) was detected.
(3) The signal color of the traffic light changed from red to blue.
(4) The level crossing warning light is turned off, or the blocking state of the blocking bar is released.

(Idle stop control method)
FIG. 6 is a flowchart showing the overall processing flow of the idle stop control method. Here, a process periodically executed by interruption is shown.

  The engine control unit 160 determines whether or not the operation amount of the accelerator pedal 12 in the host vehicle 1 is equal to or less than a predetermined threshold value (S200). If the result is equal to or less than the threshold value (YES in S200), engine control unit 160 determines whether the signal color is red or yellow, or whether the crossing is in an interrupted state (S202). As a result, if any one of the conditions is satisfied (YES in S202), engine control unit 160 determines whether there is a preceding vehicle or whether there is a preceding vehicle but has stopped or decelerated (S204). As a result, if there is no preceding vehicle, or if there is a preceding vehicle but has stopped or decelerated (YES in S204), engine control unit 160 determines whether or not the number of traveling zones is one lane on one side ( S206). As a result, if the number of traveling zones is one lane on one side (YES in S206), engine control unit 160 confirms that there is no interruption of the vehicle (S208). As a result, if there is no interruption of the vehicle (YES in S208), the engine control unit 160 confirms that the road surface gradient of the traveling road is not a downhill that is equal to or greater than a predetermined threshold (S210). As a result, if the road surface gradient is not a downhill above the threshold (YES in S210), the engine control unit 160 permits the transition to the stopped state (S212).

  Then, the engine control unit 160 causes the operating state of the engine 18 to transition to a stopped state (S214). If any of the conditions of the determination process described above is not satisfied (NO), the idle stop control method is terminated.

  As described above, in the present embodiment, an appropriate idle stop during driving is realized after the driver's intention to stop is reliably determined in consideration of the surrounding environment of the vehicle 1 through the vehicle environment recognition unit 102. To do. Therefore, an excellent fuel saving effect can be obtained.

  Also provided are a program that causes the computer to function as the idle stop control device 100 and a computer-readable storage medium such as a flexible disk, magneto-optical disk, ROM, CD, DVD, or BD on which the program is recorded. Here, the program refers to data processing means described in an arbitrary language or description method.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  Note that each step of the idle stop control method of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, and may include processing in parallel or by a subroutine.

  INDUSTRIAL APPLICABILITY The present invention can be used for an idle stop control device that changes the operating state of the engine of the host vehicle between a driving state and a stopped state according to driving conditions.

DESCRIPTION OF SYMBOLS 1 ... Own vehicle 12 ... Accelerator pedal 18 ... Engine 100 ... Idle stop control apparatus 102 ... Outside environment recognition unit 130 ... Signal color specific | specification part 132 ... Preceding vehicle specific part 134 ... Railroad crossing specific part 136 ... Traveling zone specific part 138 ... Interrupt Prediction unit 150 ... accelerator deriving unit 152 ... speed deriving unit 154 ... road surface gradient deriving unit 156 ... coasting determining unit 160 ... engine control unit

Claims (4)

An engine control unit for controlling the operating state of the engine of the host vehicle;
A coasting determination unit that determines whether or not the traveling state of the host vehicle is a coasting state;
A signal color identifying unit that identifies a signal color emitted from a traffic light located in front of the host vehicle;
A preceding vehicle specifying unit for specifying the state of the preceding vehicle;
A distance identifying unit that identifies a distance from the host vehicle to the traffic light;
A traveling zone identifying unit that identifies the number of traveling zones in the traveling direction of the host vehicle;
With
The engine control unit, the running state Ri coasting state that is the traveling band number one of a two-lane der Rutoki, the signal color is red or yellow, and the preceding vehicle is no or the preceding An idle stop control device that stops an engine when a vehicle is present but is stopped or decelerated and a distance traveled by maintaining the coasting state of the host vehicle is longer than a distance to the traffic light. An engine control unit for controlling the operating state of the engine of the host vehicle;
A coasting determination unit that determines whether or not the traveling state of the host vehicle is a coasting state;
A signal color identifying unit that identifies a signal color emitted from a traffic light located in front of the host vehicle;
A preceding vehicle specifying unit for specifying the state of the preceding vehicle;
A distance identifying unit that identifies a distance from the host vehicle to the traffic light;
The distance between the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate that is a candidate for the interrupted vehicle, the change in the distance between the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate, and An interrupt prediction unit that predicts an interruption of the vehicle forward of the host vehicle based on one of the angles formed by the planned travel path of the host vehicle and the planned travel path of the interrupt vehicle candidate;
With
The engine control unit when the running state Ri coasting state that is predicted that there is no interruption of the vehicle, the signal color is red or yellow, and the preceding vehicle is not or said prior vehicle However, the engine is stopped when the distance traveled by maintaining the coasting state is longer than the distance to the traffic light. An engine control unit for controlling the operating state of the engine of the host vehicle;
A coasting determination unit that determines whether or not the traveling state of the host vehicle is a coasting state;
A level crossing specifying unit for specifying the level of the level crossing located in front of the host vehicle;
A preceding vehicle specifying unit for specifying the state of the preceding vehicle;
A distance specifying unit for specifying a distance from the own vehicle to the crossing;
A traveling zone identifying unit that identifies the number of traveling zones in the traveling direction of the host vehicle;
With
The engine control unit, the running state Ri coasting state that is the traveling band number one of a two-lane der Rutoki, the crossing is blocked state, and the preceding vehicle is not or said prior vehicle An idle stop control device that stops an engine when the vehicle is stopped or decelerated and the distance traveled by maintaining the coasting state of the host vehicle is longer than the distance to the railroad crossing. An engine control unit for controlling the operating state of the engine of the host vehicle;
A coasting determination unit that determines whether or not the traveling state of the host vehicle is a coasting state;
A level crossing specifying unit for specifying the level of the level crossing located in front of the host vehicle;
A preceding vehicle specifying unit for specifying the state of the preceding vehicle;
A distance specifying unit for specifying a distance from the own vehicle to the crossing;
The distance between the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate that is a candidate for the interrupted vehicle, the change in the distance between the planned travel path of the host vehicle and the planned travel path of the interrupted vehicle candidate, and An interrupt prediction unit that predicts an interruption of the vehicle forward of the host vehicle based on one of the angles formed by the planned travel path of the host vehicle and the planned travel path of the interrupt vehicle candidate;
With
The engine control unit, the running state Ri coasting state that is when it is predicted that no interruption of the vehicle, the crossing is blocked state, and the preceding vehicle is not or said prior vehicle is Is stopped or decelerated, and the engine is stopped when the distance traveled by maintaining the coasting state of the host vehicle is longer than the distance to the railroad crossing.