JP2008006878A - Vehicular traveling controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a sense of incongruity given to a driver due to vehicle acceleration, concerning a vehicular traveling controller. <P>SOLUTION: In the vehicular traveling controller executing traveling control making one's own vehicle travel at target acceleration (a), it is detected whether one's own vehicle lane is a traveling lane or a passing lane, as a traveling state of the own vehicle. Brightness around the own vehicle is detected, and an operation state of a vehicle wiper is detected. When the own vehicle is in the passing lane, the target acceleration (a) in traveling control is made to be larger as compared with that when the own vehicle is in the traveling lane. Furthermore, the target acceleration (a) is made to be smaller as the brightness around the own vehicle is low and dark, and made to be smaller as the operation state of the vehicle wiper is fast. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicular travel control device, and more particularly to a vehicular travel control device that is suitable for driving a host vehicle at a target acceleration when following a preceding vehicle or traveling at a constant speed at a predetermined vehicle speed.

2. Description of the Related Art Conventionally, there has been known an apparatus that causes a host vehicle to travel at a target vehicle speed set by a driver (see, for example, Patent Document 1). In this device, when the host vehicle is driven at the target vehicle speed, the target acceleration for bringing the host vehicle speed close to the target vehicle speed can be arbitrarily changed by the driver's selection. For this reason, according to the above-described conventional apparatus, the host vehicle can be accelerated to the target vehicle speed at the target acceleration selected by the driver.
JP 2002-248966 A

  In general, even if the acceleration is the same, the acceleration feeling given to the driver varies depending on the traveling environment such as the traveling environment of the host vehicle and the surrounding conditions. However, in the above conventional apparatus, even if the driver can arbitrarily set the target acceleration, the target acceleration is uniformly determined regardless of the traveling state of the own vehicle. When following the preceding vehicle takes a long time when the vehicle is accelerated to travel at the target vehicle speed by changing the lane of the preceding vehicle, etc. May give the driver a sense of incongruity for the same acceleration as compared to when it ends in a short time.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a vehicular travel control device that can reduce a sense of discomfort given to a driver by vehicle acceleration.

  The above object is a vehicle travel control device that executes travel control for accelerating the host vehicle at a target acceleration, and includes a travel state detection unit that detects a travel state of the host vehicle, and a detection result of the travel state detection unit. Accordingly, the present invention is achieved by a vehicle travel control device comprising target acceleration changing means for changing the target acceleration in the travel control.

  In the invention of this aspect, the target acceleration of the host vehicle in the traveling control is changed according to the traveling state of the host vehicle. When the host vehicle is accelerated by running control, when it is in a driving situation that gives the vehicle driver an excessive feeling of acceleration, it is in a driving situation that gives the driver a little feeling of acceleration. In comparison, reducing the target acceleration is appropriate for reducing the uncomfortable feeling given to the driver. Therefore, according to the present invention, it is possible to reduce the uncomfortable feeling given to the driver by the vehicle acceleration by setting an appropriate target acceleration corresponding to the driving situation.

  For example, in a situation where traveling control is performed on an expressway or the like, it can be determined that the driver desires a greater acceleration when traveling on the overtaking lane than when traveling on the traveling lane. Therefore, in the vehicle travel control apparatus described above, the travel state detection means detects whether the lane in which the host vehicle travels is a travel lane or an overtaking lane adjacent to the travel lane, and the target acceleration. When the travel state detection unit detects that the lane on which the host vehicle is traveling is an overtaking lane, the change unit detects the target in the travel control as compared to the case where it is detected that the lane is a travel lane. If the acceleration is increased, the feeling of acceleration given to the driver during traveling in the overtaking lane is not impaired, and the uncomfortable feeling given to the driver by vehicle acceleration can be reduced.

  In addition, when traveling control is performed at night, the periphery of the vehicle is relatively dark compared to when traveling control is performed during the daytime, and thus the driver may feel a large acceleration even at the same acceleration. Therefore, in the vehicle travel control apparatus described above, the travel condition detection means detects the illuminance around the own vehicle, and the target acceleration changing means is such that the illuminance around the own vehicle is dark by the travel condition detection means. If the target acceleration in the travel control is made smaller, the driver is not given an excessive feeling of acceleration, and the uncomfortable feeling given to the driver by the vehicle acceleration can be reduced.

  Also, when it is raining or snowing, the field of view is poorer than when it is not falling, so the driver may feel a large acceleration at the same acceleration. Therefore, in the vehicle travel control apparatus described above, the travel state detection means detects the operation state of the vehicle wiper, and the target acceleration changing means detects that the operation state of the vehicle wiper is at a high speed operation state by the travel state detection means. If the target acceleration in the travel control is made smaller, the driver is not given an excessive feeling of acceleration, and the uncomfortable feeling given to the driver by the vehicle acceleration can be reduced.

  In the vehicle travel control apparatus described above, the target acceleration in the travel control is the target inter-vehicle distance or the target inter-vehicle time, which is the inter-vehicle distance or inter-vehicle time between the own vehicle and the preceding vehicle when the host vehicle follows the preceding vehicle. May be the acceleration of the host vehicle required to match the vehicle speed or the acceleration of the host vehicle required to drive the host vehicle at the target vehicle speed. In this case, the “target inter-vehicle distance” is a distance that should be provided between the own vehicle and the preceding vehicle in the follow-up control, and the “target inter-vehicle time” is the distance between the own vehicle and the preceding vehicle in the follow-up control. This is the time required to reach the position.

  In addition, the above object is to make the host vehicle run at a constant speed at the target vehicle speed, and when there is a preceding vehicle ahead of the host vehicle, the host vehicle maintains the target inter-vehicle distance or the target inter-vehicle time with the preceding vehicle. A vehicle travel control device that executes travel control for following travel, the following travel duration measuring means for measuring the duration of follow-up travel to the preceding vehicle in the travel control, and the travel control following the preceding vehicle. Vehicular travel control device comprising: target acceleration changing means for changing a target acceleration in the case of shifting from running to constant speed running at a target vehicle speed according to the duration measured by the following running duration measuring means. Is achieved.

  In the aspect of the invention, the target acceleration when the travel control shifts from the follow-up traveling to the preceding vehicle to the constant speed travel at the target vehicle speed is changed according to the duration of the follow-up traveling to the preceding vehicle. In the case where the travel control shifts from the follow-up traveling to the preceding vehicle to the constant speed travel at the target vehicle speed, the longer the duration of the follow-up traveling to the preceding vehicle so far, the faster the driver Therefore, it is appropriate to reduce the target acceleration to reduce the driver's uncomfortable feeling. Therefore, according to the present invention, by setting an appropriate target acceleration corresponding to the duration of the follow-up traveling to the preceding vehicle, the uncomfortable feeling given to the driver by the vehicle acceleration can be reduced.

  In this case, in the vehicle travel control apparatus described above, the target acceleration changing unit may decrease the target acceleration as the duration time measured by the following travel duration measurement unit increases.

  The vehicle travel control apparatus may further include a travel condition detection unit that detects whether a lane in which the vehicle travels is a travel lane or an overtaking lane adjacent to the travel lane, and the target acceleration change unit. Further, when the travel condition detecting means detects that the lane on which the host vehicle is traveling is an overtaking lane, the target acceleration is increased as compared with the case where it is detected that the lane is a traveling lane. If this is done, the feeling of acceleration given to the driver when traveling on the overtaking lane is not impaired, and the feeling of strangeness given to the driver by vehicle acceleration can be reduced.

  In the vehicular travel control device described above, acceleration of the host vehicle starts at the target acceleration by the target acceleration changing means when the travel control shifts from following travel to the preceding vehicle to constant speed travel at the target vehicle speed. If the vehicle is provided with acceleration increasing means for increasing the target acceleration of the host vehicle from the target acceleration by the target acceleration changing means as time elapses, the followability to the target vehicle speed deteriorates. It becomes possible to prevent.

  Further, the above object is achieved when a preceding vehicle detecting means for detecting a preceding vehicle existing within a predetermined range ahead of the host vehicle and a preceding vehicle existing within the predetermined range are detected by the preceding vehicle detecting means. A vehicle travel control device that executes follow-up control for causing the host vehicle to follow the host vehicle while maintaining a target inter-vehicle distance or target inter-vehicle time, and a road in a traveling direction of the host vehicle. A road shape detecting means for detecting straightness of the shape, and the predetermined range in which the preceding vehicle existing by the preceding vehicle detecting means should be detected is changed according to the straightness of the road shape detected by the road shape detecting means. And a preceding vehicle detection range changing means.

  In the invention of this aspect, the predetermined range in which the preceding vehicle existing in front of the host vehicle is to be detected is changed according to the straightness of the road shape. Considering that the road becomes a curved road, it is desirable that the predetermined range in which the preceding vehicle should be detected is relatively narrow in order to prevent the erroneous detection. On the other hand, when the straight road is maintained long, the preceding vehicle is Even if the predetermined range to be detected is relatively wide, the erroneous detection is avoided, and the preceding vehicle can be detected at a relatively early timing. If the preceding vehicle can be detected at a relatively early timing, then the follow-up control with acceleration / deceleration of the host vehicle can be started at an early stage, and the occurrence of unnecessarily large acceleration / deceleration can be suppressed. For this reason, according to this invention, the discomfort given to a driver | operator by vehicle acceleration can be reduced.

  In this case, in the vehicle travel control apparatus described above, the preceding vehicle detection range changing means detects the preceding vehicle compared to a case where the straightness of the road shape detected by the road shape detecting means is low. What is necessary is just to expand the said predetermined range which should detect the preceding vehicle which exists by a means.

  According to the present invention, it is possible to reduce the uncomfortable feeling given to the driver by vehicle acceleration.

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

  FIG. 1 is a system configuration diagram of a vehicular travel control apparatus 10 mounted on a vehicle according to a first embodiment of the present invention. The vehicle travel control apparatus 10 according to the present embodiment includes a control (hereinafter referred to as a follow-up control) that causes the host vehicle to travel following the preceding vehicle that travels in the same direction as the host vehicle on the host lane, This is a cruise control system that executes control for causing the host vehicle to travel at a constant speed at a predetermined vehicle speed (hereinafter referred to as constant speed control) as travel control when no vehicle is present.

  As shown in FIG. 1, the vehicle travel control apparatus 10 includes an electronic control unit (hereinafter referred to as a control ECU) 12 mainly composed of a computer. A cruise control switch 14 and an inter-vehicle distance setting switch 16 that can be operated by the vehicle driver are connected to the control ECU 12. The cruise control switch 14 is a switch for turning on / off tracking control and constant speed control as traveling control. The inter-vehicle distance setting switch 16 is a switch for switching the target inter-vehicle distance when the follow-up control is executed in multiple stages (for example, three stages of short mode, medium mode, and long mode). Based on the state of the cruise control switch 14, the control ECU 12 determines whether or not the execution condition for the travel control is satisfied, and determines the target inter-vehicle distance in the follow-up control based on the state of the inter-vehicle distance setting switch 16. Set according to your will.

  Also connected to the control ECU 12 are a vehicle speed sensor 18 disposed on a wheel or the like, and a radar sensor 20 disposed on a bumper or a front grille at the front end of the vehicle body. The vehicle speed sensor 18 outputs a signal corresponding to the vehicle speed of the host vehicle to the control ECU 12. The radar sensor 20 is configured by, for example, a millimeter wave radar, a laser radar, a camera, or the like, and a signal corresponding to an obstacle (specifically, a preceding vehicle) existing within a predetermined range in front of the host vehicle is transmitted to the control ECU 12. Output for. The control ECU 12 detects the vehicle speed of the host vehicle based on the output signal of the vehicle speed sensor 18. Further, the control ECU 12 detects the presence or absence of a preceding vehicle that travels on the own lane on which the host vehicle should be careful based on the output signal of the radar sensor 20, and when the preceding vehicle exists, the control ECU 12 The distance between the vehicle and the preceding vehicle and the relative speed are detected.

  A navigation ECU 22 is also connected to the control ECU 12. The navigation ECU 22 has a database that stores road map data, road type, data indicating the number of lanes and curvature for each road, and the like. A GPS receiver 24 and a rear camera 26 are connected to the navigation ECU 22. The GPS receiver 24 receives GPS signals transmitted from GPS satellites. A reception signal of the GPS receiver 24 is supplied to the navigation ECU 22. The rear camera 26 is disposed on a bumper or the like at the rear end of the vehicle body, and photographs a road surface extending behind the host vehicle. The image signal of the rear camera 26 is supplied to the navigation ECU 22.

  The navigation ECU 22 detects the type, number of lanes, curvature, and position of the road on which the host vehicle travels based on the received signal from the GPS receiver 24 and the image signal from the rear camera 26, and the host vehicle travels. A lane drawn on the road is extracted, and the position of the traveling lane of all the lanes on the road on which the host vehicle is traveling is detected. Data detected by the navigation ECU 22 is supplied to the control ECU 12. The control ECU 12 acquires various types of information about the road on which the host vehicle travels based on data from the navigation ECU 22.

  An illuminance sensor 28 and a wiper switch 30 are also connected to the control ECU 12. The illuminance sensor 28 outputs a signal corresponding to the illuminance around the host vehicle to the control ECU 12. The wiper switch 30 is a switch for switching the operation / stop and operation speed of the vehicle wiper for wiping the vehicle windshield, and the operation is switched by a switch operation of the vehicle driver or by detection of rain or snow. The control ECU 12 detects the illuminance around the host vehicle based on the output of the illuminance sensor 28, determines whether or not the vehicle wiper is operating based on the state of the wiper switch 30, and further operates. Sometimes the operating speed is also detected.

  An accelerator pedal sensor 32 and a throttle actuator 34 are also connected to the control ECU 12. The accelerator pedal sensor 32 is disposed in the vicinity of the accelerator pedal operated by the vehicle driver and outputs a signal corresponding to the opening of the accelerator pedal to the control ECU 12. The control ECU 12 detects the accelerator pedal opening by the vehicle driver based on the output signal of the accelerator pedal sensor 32. The throttle actuator 34 is an actuator for opening intake air into the engine by opening a throttle valve of the vehicle. The control ECU 12 calculates the opening degree to be realized of the throttle valve based on the accelerator pedal opening degree or the target acceleration calculated as described in detail later, and sends a drive command to the throttle actuator 34 so that the throttle opening degree is realized. I do. The throttle actuator 34 opens a throttle valve in accordance with a drive command from the control ECU 12, thereby introducing an appropriate amount of intake air to the engine and applying an appropriate driving force to the vehicle.

  Next, the operation of the vehicle travel control apparatus 10 of this embodiment will be described. FIG. 2 shows a map used for calculating the basic target acceleration a0 when the control ECU 12 executes the follow-up control and the constant speed control as the travel control in the vehicle travel control apparatus 10 of the present embodiment. The figure is shown. FIG. 3 shows a flowchart of an example of a control routine executed by the control ECU 12 in the vehicle travel control apparatus 10 of the present embodiment. 4 to 7 show the basic target acceleration for obtaining the target acceleration a when the control ECU 12 executes the follow-up control and the constant speed control as the travel control in the vehicle travel control apparatus 10 of the present embodiment. The figure showing the map used for correct | amending a0 is shown.

  In this embodiment, the control ECU 12 includes an ACC basic target acceleration 40, an ACC target acceleration correction coefficient calculation unit 42, an ACC target acceleration determination unit 44, and a throttle opening adjustment / calculation unit 46.

  First, the control ECU 12 determines whether or not the execution conditions for the follow-up control and the constant speed control as the travel control are satisfied at predetermined time intervals (step 100). This condition is that the cruise control switch 14 is permitted to execute the travel control by the operation of the vehicle driver (on state) and the vehicle speed based on the vehicle speed sensor 18 is within the range where the execution of the travel control is permitted ( For example, it is established when the speed is 40 km / h or more.

  As a result of the above determination, if the execution condition of the travel control is satisfied, the current vehicle speed at that time is set as the target vehicle speed to be traveled at a constant speed by the constant speed control, and thereafter the travel speed is The following processing is executed until control execution is canceled. It should be noted that the target vehicle speed may be made variable by the driver's acceleration operation or deceleration operation even after it has been set once.

  The control ECU 12 takes in the target vehicle speed Va set as described above, and based on the output signal of the vehicle speed sensor 18, the state of the inter-vehicle distance setting switch 16, and the output signal of the radar sensor 20, the current vehicle speed V0 of the host vehicle, The inter-vehicle distance setting value (target inter-vehicle distance) during follow-up control and information related to the preceding vehicle (specifically, the presence / absence, inter-vehicle distance, and relative speed) are fetched (step 102). Then, it is determined whether or not there is a preceding vehicle in a predetermined range on the own lane on the road in the traveling direction on which the own vehicle travels based on the information related to the captured preceding vehicle (step 104).

  As a result of the determination, if there is no preceding vehicle on the own lane, next, the basic target acceleration a0 is first set to the ACC basic target acceleration in order to execute constant speed control that causes the own vehicle to travel at the target vehicle speed Va. Calculation is performed at 40 (step 106). The calculation of the basic target acceleration a0 is performed with reference to the maps as shown in FIGS. 2A to 2C, and specifically, the target vehicle speed Va with respect to the vehicle speed deviation between the target vehicle speed Va and the current vehicle speed V0. Is proportionally increased as the vehicle speed is greater than the current vehicle speed V0 (FIG. 2A), and is decreased as the current vehicle speed V0 is increased (FIG. 2B). The calculation is performed using a predetermined arithmetic expression f shown in the following expression (1) so as to decrease as the length increases (FIG. 2C).

a0 = f ((vehicle speed deviation), (own vehicle speed), (acceleration elapsed time)) (1)
Next, based on the data supplied from the navigation ECU 22, the output signal of the illuminance sensor 28, and the state of the wiper switch 30, the control ECU 12 sets at least all the lanes of the own lane on which the own vehicle travels as the traveling status of the own vehicle. Various information on the road on which the host vehicle is traveling, including the position of the vehicle, the illuminance around the host vehicle, and the operating state of the vehicle wiper are captured (step 108). Then, based on the various data taken in, it is calculated in the above step 106 that is necessary to calculate the target acceleration a that should be the target of the host vehicle at the present time in order to realize the constant speed traveling at the target vehicle speed Va. The ACC target acceleration correction coefficient calculation unit 42 calculates an acceleration correction coefficient Ka to be multiplied by the basic target acceleration a0 (step 110).

  The calculation of the acceleration correction coefficient Ka is performed with reference to the maps as shown in FIGS. 4 to 7, and specifically, the longer the target inter-vehicle distance during the follow-up control is set, the smaller it becomes inversely proportionally. (FIG. 4), when the own lane on which the vehicle is traveling is an overtaking lane out of all lanes on an automobile road with two or more lanes on one side, it is larger than when the lane is adjacent to the overtaking lane. As shown in FIG. 5, the lower the illuminance around the host vehicle is, the smaller the darkness is (FIG. 6), and the smaller the operation state of the vehicle wiper is, the higher the operation state is (FIG. 7). ), Using a predetermined arithmetic expression g shown in the following expression (2).

  The acceleration correction coefficient Ka is changed linearly as shown in FIG. 4 and FIG. 6 according to the set target inter-vehicle distance and illuminance, but is not limited to this, and is changed to a curved line convex downward or upward. Even if it is a thing, it may be changed to step shape. In addition, it is changed as shown in FIG. 7 according to the operation state of the vehicle wiper. At this time, it is changed linearly, downwardly or upwardly in a convex curve shape, or in a staircase shape according to the operation speed. May be.

Ka = g ((target vehicle distance), (running lane), (illuminance), (wiper operating state))
... (2)
On the other hand, if the result of determination in step 104 is that there is a preceding vehicle on the own lane, the control ECU 12 first performs a basic target acceleration to execute follow-up control that causes the own vehicle to follow the preceding vehicle. a0 is calculated in the ACC basic target acceleration 40 (step 112). The calculation of the basic target acceleration a0 is performed based on the deviation between the set target inter-vehicle distance during follow-up control and the actual inter-vehicle distance between the host vehicle and the preceding vehicle, and the relative speed between the host vehicle and the preceding vehicle. Specifically, in order to increase the inter-vehicle distance deviation as the actual inter-vehicle distance increases, and to increase the relative speed as the host vehicle increases toward the deceleration side, that is, away from the preceding vehicle, the following equation ( This is performed using a predetermined arithmetic expression f shown in 3).

a0 = f ((Vehicle distance deviation), (Relative speed)) (3)
Then, the control ECU 12 calculates the basic target acceleration a0 calculated in step 106, which is necessary for calculating the target acceleration a that should be the target of the host vehicle at the present time in order to realize constant speed traveling at the target vehicle speed Va. Is set to "1" (step 114).

  As described above, the control ECU 12 calculates the basic target acceleration a0 (step 106 or 112) and calculates the acceleration correction coefficient Ka (step 110 or 114). Next, the control ECU 12 adds the acceleration correction coefficient to the basic target acceleration a0. By multiplying Ka, the target acceleration a that should be the target of the host vehicle is calculated in the ACC target acceleration determining unit 44 (step 116). Then, the throttle opening adjusting / calculating unit 46 calculates the opening degree of the throttle valve based on the calculated target acceleration a (step 118), and the throttle actuator so that the throttle opening degree is realized. A drive command is issued to 34. In this case, the throttle actuator 34 opens the throttle valve to an appropriate opening in accordance with a drive command from the control ECU 12, thereby introducing an appropriate amount of intake air into the engine and realizing the target acceleration a in the vehicle. Provide an appropriate driving force.

  When the above process is repeated, the follow-up control is executed when the preceding vehicle is present on the own lane, and the vehicle speed of the preceding vehicle is higher than the vehicle speed of the own vehicle, and the own vehicle tends to leave the preceding vehicle. Sometimes, the host vehicle is accelerated so as to maintain the target inter-vehicle distance, and after reaching the target inter-vehicle distance, the vehicle travels following the preceding vehicle while maintaining the target inter-vehicle distance in accordance with the vehicle speed change of the preceding vehicle. On the other hand, when there is no preceding vehicle on the own lane due to, for example, a lane change of the preceding vehicle on the own lane during the follow-up control, constant speed control is executed, and when the own vehicle speed V0 is lower than the target vehicle speed Va. The vehicle is accelerated toward the target vehicle speed Va, and after reaching the target vehicle speed Va, the vehicle travels while maintaining the target vehicle speed Va.

  Here, in the constant speed control, the target acceleration a to be applied to the vehicle is calculated based on the vehicle speed deviation between the host vehicle speed V0 and the target vehicle speed Va, the host vehicle speed V0, and the elapsed time from the start of acceleration. If it is a0, the target acceleration a is determined regardless of the traveling state of the host vehicle. Therefore, when the vehicle is accelerated at the target acceleration a, the vehicle is driven with the same acceleration depending on the traveling state. May feel uncomfortable.

  For example, when the vehicle travels in an overtaking lane on an automobile-only road, the driver wants the vehicle to travel at a constant speed with great acceleration compared to traveling in the travel lane. Therefore, if acceleration is performed at the same target acceleration a as when traveling in the travel lane, the driver may feel that the desired acceleration has not been obtained. Also, when driving on a dark road with low illuminance, the driver can determine that the driver tends to feel a large acceleration even at the same acceleration compared to driving on a light road with high illuminance. If acceleration is performed with the same target acceleration a as when traveling on a bright road, the driver may feel that excessive acceleration has been obtained. Furthermore, when the vehicle travels on a road where rain or snow falls, the driver can determine that the driver tends to feel a large acceleration even at the same acceleration as compared to when the vehicle travels on the road where it does not rain. Therefore, if acceleration is performed at the same target acceleration a as when traveling on a road where snow is not falling, the driver may feel that excessive acceleration has been obtained.

  In contrast, in the vehicle travel control apparatus 10 of the present embodiment, the target acceleration a to be applied to the vehicle when the constant speed control is executed is the vehicle speed deviation between the host vehicle speed V0 and the target vehicle speed Va, the host vehicle speed V0. And the basic target acceleration a0 calculated based on the elapsed time from the start of acceleration is obtained by adding a correction that multiplies the acceleration correction coefficient Ka according to the traveling state of the host vehicle.

  Specifically, when the own lane is an overtaking lane, a larger acceleration correction coefficient Ka is set by calculation and a larger target acceleration a is obtained than when it is a traveling lane. Further, when the illuminance around the host vehicle is low and dark, the smaller the illuminance is, the smaller the acceleration correction coefficient Ka is set by calculation and the smaller target acceleration a is obtained. Further, when the operation state of the vehicle wiper is slow (including operation stop), the acceleration correction coefficient Ka is set smaller by calculation as the operation is faster than when it is faster. A target acceleration a is obtained.

  Therefore, in the vehicle travel control apparatus 10 of the present embodiment, the target acceleration a when the constant speed control of the host vehicle is performed can be changed depending on the traveling state of the host vehicle. Specifically, the target acceleration a can be set larger when traveling on an overtaking lane than when traveling on a traveling lane. In addition, it can be set smaller as the surroundings of the vehicle such as night driving are in a dark environment. Furthermore, it can be set smaller as the weather such as rainy weather gets worse.

  For this reason, in constant speed control, the vehicle is accelerated at a greater acceleration when traveling in the overtaking lane than when traveling in the traveling lane, so it is avoided that the vehicle driver feels insufficient acceleration. Is done. In addition, since the host vehicle is accelerated at a smaller acceleration as the environment around the vehicle is darker, such as driving at night, it is avoided that the vehicle driver feels a large acceleration. Furthermore, since the host vehicle is accelerated at a smaller acceleration as the weather such as running on rainy weather gets worse, it is avoided that the vehicle driver feels a large acceleration.

  Thus, according to the vehicle travel control apparatus 10 of the present embodiment, when the own vehicle is accelerated by executing constant speed control, for example, by changing the lane of the preceding vehicle that is the target of the follow-up control, the acceleration is performed. Since it is performed with acceleration according to the driving situation of the vehicle and matches the driver's intention, it is possible to reduce the uncomfortable feeling given to the driver by vehicle acceleration, and appropriate driving control can be performed. It is possible to execute.

  In the first embodiment, the control ECU 12 detects whether the lane on which the host vehicle is traveling is a traveling lane or an overtaking lane adjacent to the traveling lane based on data from the navigation ECU 22. In addition, by detecting the illuminance around the host vehicle based on the output signal of the illuminance sensor 28, or detecting the operating state of the vehicle wiper based on the state of the wiper switch 30, the "travel situation" Depending on whether the own lane is a driving lane or an overtaking lane, the detection means "depends on the illuminance around the own vehicle or on the operating state of the vehicle wiper, and the target acceleration a in the constant speed control The “target acceleration changing means” described in the claims is realized by changing the above.

  By the way, in the first embodiment, the target acceleration a to be applied to the vehicle in the constant speed control is changed according to various traveling situations, but is applied to the vehicle in the follow-up control following the preceding vehicle. The target acceleration a to be changed may be changed according to various traveling situations.

  Moreover, in said 1st Example, as the target acceleration a which should be provided to a vehicle is changed according to three driving | running | working conditions of the position of the own lane, the illumination intensity around the own vehicle, and the operation state of a vehicle wiper. However, it may be changed according to at least one of the traveling situations.

  In the first embodiment described above, the target acceleration a to be given to the vehicle is changed in accordance with the position of the own lane, the illuminance around the own vehicle, and the traveling state of the operating state of the vehicle wiper. On the other hand, in the second embodiment of the present invention, in the follow-up control, the preceding vehicle retreats from the front of the own vehicle due to lane change or acceleration, so that the travel control of the own vehicle shifts from the follow-up control to the constant speed control. In this case, the target acceleration a is changed according to the time during which the follow-up control is continued. Hereinafter, the characteristic part of the present embodiment will be described with reference to FIGS. In the present embodiment, the same components as those shown in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  FIG. 8 schematically shows a situation in which the target acceleration a calculated in the vehicle travel control apparatus 10 of the present embodiment changes with time. FIG. 9 shows a flowchart of an example of a control routine executed by the control ECU 12 in the vehicle travel control apparatus 10 of the present embodiment. FIG. 10 shows a map used for correcting the basic target acceleration a0 when the control ECU 12 obtains the target acceleration a when shifting from the follow-up control to the constant speed control in the vehicle travel control apparatus 10 of the present embodiment. The figure is shown. FIG. 11 is a map used for correcting the basic target acceleration a0 when the control ECU 12 obtains the target acceleration a after completing the transition from the follow-up control to the constant speed control in the vehicle travel control apparatus 10 of the present embodiment. The figure showing is shown.

  In this embodiment, when the control ECU 12 takes in the set target vehicle speed Va, the current vehicle speed V0 of the host vehicle, the target inter-vehicle distance, and the preceding vehicle information in step 102, the control ECU 12 travels from the previous process to the current process. It is determined whether or not the situation in which the preceding vehicle exists within a predetermined range on the own lane on the road in the traveling direction leads to a situation where it does not exist (step 200).

  As a result of the determination, if the situation where the preceding vehicle is present in front of the host vehicle is changed to a state where the preceding vehicle is not present, that is, the travel control is shifted from the follow-up control to the constant speed control, then the host vehicle is In order to execute the constant speed control for running, first, the basic target acceleration a0 is calculated in the ACC basic target acceleration 40 as described above (step 202), and from the start to the end of the follow-up control counted until the transition. The duration Tt is measured (step 204). Based on the duration Tt of the follow-up control, an acceleration correction coefficient Ka to be multiplied by the basic target acceleration a0 is calculated in the ACC target acceleration correction coefficient calculation unit 42 (step 206).

  The calculation of the acceleration correction coefficient Ka is performed with reference to a map as shown in FIG. 10, and specifically, the acceleration correction coefficient Ka is performed so as to decrease as the duration Tt during which the follow-up control has continued. As shown in FIG. 10, the acceleration correction coefficient Ka is a normal value Ka0 (eg, “1”) when the duration Tt is less than Tt0, and is downward when the duration Tt is equal to or longer than Tt0. Although it may be changed to a convex curve, it may be changed linearly or upward to a convex curve depending on the duration Tt.

  On the other hand, if the result of determination in step 200 is negative, it is next determined whether or not the currently set acceleration correction coefficient Ka is less than Ka0 (step 208). If it is determined that Ka <Ka0 is established, then the basic target acceleration a0 is calculated in the ACC basic target acceleration 40 as described above (step 210), and the vehicle is accelerated by shifting from the follow-up control to the constant speed control. The acceleration continuation time Ta from the start to the present time is counted (step 212). Based on the acceleration continuation time Ta, an acceleration correction coefficient Ka to be multiplied by the basic target acceleration a0 is calculated in the ACC target acceleration correction coefficient calculation unit 42 (step 214).

  The calculation of the acceleration correction coefficient Ka is performed with reference to a map as shown in FIG. 11. Specifically, the acceleration correction coefficient Ka is performed so that the acceleration start time Ta increases from the value Ka1 at the start of acceleration. As shown in FIG. 11, the acceleration correction coefficient Ka is changed from a value Ka1 at the start of acceleration to a linear (inclination α) according to the subsequent acceleration duration Ta. However, the acceleration correction coefficient Ka is not limited to this and is downward or upward. It may be changed to a convex curve shape or may be changed to a staircase shape.

  If it is determined in step 208 that Ka <Ka0 is not satisfied, that is, Ka = Ka0 is satisfied, then the basic target acceleration a0 is calculated in the ACC basic target acceleration 40 as usual (step 216). ). For example, when the follow-up control is executed, the calculation is performed based on the deviation between the target inter-vehicle distance and the actual inter-vehicle distance and the relative speed between the host vehicle and the preceding vehicle. On the other hand, when the constant speed control is executed, the target vehicle speed of the host vehicle is calculated. The calculation is based on the vehicle speed deviation between Va and the current vehicle speed V0, the current vehicle speed V0 itself, and the elapsed time from the start of acceleration. Then, the acceleration correction coefficient Ka is set to the normal value Ka0 (step 218).

  As described above, the control ECU 12 calculates the basic target acceleration a0 (steps 202, 210, or 216) and calculates the acceleration correction coefficient Ka (steps 206, 214, or 218). By multiplying the acceleration a0 by the acceleration correction coefficient Ka, the target acceleration a that should be the target of the host vehicle is calculated in the ACC target acceleration determination unit 44 (step 220). Then, the throttle opening adjusting / calculating unit 46 calculates the opening degree of the throttle valve based on the calculated target acceleration a (step 222), and the throttle actuator so that the throttle opening degree is realized. A drive command is issued to 34. In this case, the throttle actuator 34 opens the throttle valve to an appropriate opening in accordance with a drive command from the control ECU 12, thereby introducing an appropriate amount of intake air into the engine and realizing the target acceleration a in the vehicle. Provide an appropriate driving force.

  Here, when the traveling control of the host vehicle shifts from the tracking control that travels following the preceding vehicle to the constant speed control that travels at the target vehicle speed (FIG. 8A → FIG. 8B), As the operation continues for a long time, the driver may feel that the vehicle is excessively accelerating with respect to the same acceleration, and feel uncomfortable.

  In contrast, in the vehicle travel control apparatus 10 of the present embodiment, the target acceleration a to be applied to the vehicle at the time of transition from the follow-up control to the constant speed control is the own vehicle speed V0 and the target vehicle speed Va. Is obtained by multiplying the basic target acceleration a0 calculated based on the vehicle speed deviation of the vehicle, the host vehicle speed V0, and the elapsed time from the start of acceleration by an acceleration correction coefficient Ka corresponding to the duration Tt of the follow-up control that has been continued. Is obtained. Specifically, as the duration Tt of the follow-up control is longer, a smaller acceleration correction coefficient Ka is set by calculation, and a smaller target acceleration a is obtained.

  Therefore, in the vehicle travel control apparatus 10 of the present embodiment, when the travel control of the host vehicle shifts from the follow-up control to the constant speed control, the target acceleration a is changed depending on the duration Tt of the follow-up control. can do. Specifically, the target acceleration a can be set smaller as the duration Tt of the follow-up control is longer. For this reason, the longer the duration Tt of the follow-up control, the faster the host vehicle is accelerated with a smaller acceleration, so that it is avoided that the vehicle driver feels a large acceleration.

  As described above, according to the vehicle travel control apparatus 10 of the present embodiment, at the time of the transition of the travel control from the follow-up control to the constant speed control, the acceleration is performed with the acceleration corresponding to the duration Tt of the follow-up control. Since it matches the intention of the driver, it is possible to reduce the uncomfortable feeling given to the driver by the vehicle acceleration, and it is possible to execute appropriate traveling control.

  Further, in this embodiment, as described above, at the time of transition from the follow-up control to the constant speed control, the acceleration correction coefficient Ka corresponding to the duration Tt of the follow-up control is calculated, and the acceleration correction coefficient Ka is the basic value. By multiplying the target acceleration a0, the target acceleration a is calculated, and the smaller the target acceleration a is set as the duration Tt of the follow-up control is longer, but the same acceleration correction coefficient Ka is continuously used thereafter. If the target acceleration a is set, the followability of the host vehicle to the target vehicle speed Va due to execution of constant speed control may be deteriorated.

  On the other hand, in the vehicle travel control apparatus 10 of the present embodiment, the target acceleration that is suppressed more than usual according to the duration Tt of the follow-up control after the transition of the run control from the follow-up control to the constant speed control is completed. The acceleration duration time Ta after the acceleration at a is started is counted, and the target acceleration a is obtained by adding a correction that multiplies the basic target acceleration a by the acceleration correction coefficient Ka corresponding to the duration time Ta. It is done. Specifically, as the acceleration duration Ta becomes longer, an acceleration correction coefficient Ka larger than the value Ka1 at the start of acceleration is set by calculation, and a target acceleration a larger than that at the start of acceleration is obtained. Such processing is continuously performed until the acceleration correction coefficient Ka reaches the normal value Ka1 (FIG. 8C).

  Therefore, in the vehicle travel control apparatus 10 of the present embodiment, after the travel control of the host vehicle shifts from the follow-up control to the constant speed control, the target acceleration a is changed depending on the subsequent acceleration duration Ta. be able to. Specifically, the target acceleration a can be set larger as the acceleration duration Ta is longer. For this reason, even when the acceleration of the host vehicle is started at the target acceleration a that is suppressed according to the duration Tt of the follow-up control when the travel control shifts from the follow-up control to the constant speed control, the acceleration duration Ta is long. Thus, the host vehicle tends to be gradually accelerated with a large acceleration to reach the basic target acceleration a0. Therefore, it is possible to prevent the followability to the target vehicle speed in the constant speed control from being deteriorated.

  Thus, according to the vehicle travel control apparatus 10 of the present embodiment, after the transition of the travel control from the follow-up control to the constant speed control is completed, the acceleration is performed with the acceleration according to the acceleration duration Ta. The uncomfortable feeling given to the driver by the acceleration of the vehicle can be reduced, and appropriate traveling control can be executed.

  In the second embodiment, the control ECU 12 executes the process of step 204 in the routine shown in FIG. 9 so that the “following travel duration measuring means” described in the claims is changed from the follow control. The “target acceleration changing means” described in the claims changes from the follow-up control to the constant speed control by changing the target acceleration a at the time of the transition of the running control to the constant speed control according to the duration Tt of the follow-up control. By increasing the acceleration correction coefficient Ka with the lapse of the duration time Ta after the start of acceleration, the target acceleration a after completion of the travel control transition of the vehicle is increased to increase the acceleration acceleration means described in the claims. "Is realized.

  By the way, in the second embodiment, the acceleration correction coefficient Ka for multiplying the basic target acceleration a0 necessary for calculating the target acceleration a when the traveling control is shifted from the follow-up control to the constant speed control is shown in FIG. 10 is changed according to the duration Tt of the follow-up control according to the map shown in FIG. 10, but at this time, as shown in FIG. Different from the map used when the vehicle is in the over lane, the acceleration correction coefficient Ka for multiplying the basic target acceleration a0 is made different between when the host vehicle is traveling on the overtaking lane and when the vehicle is traveling on the overtaking lane. It is good.

  That is, when the host vehicle travels on the overtaking lane on the automobile exclusive road, the driver travels at a constant speed at the target vehicle speed Va with a large acceleration, compared to when traveling on the travel lane. Therefore, if the same acceleration correction coefficient Ka is calculated as when traveling in the traveling lane and acceleration is performed at the same target acceleration a, the feeling of acceleration given to the driver during traveling in the overtaking lane is impaired. The driver may feel that the ability to follow the target vehicle speed is poor.

  Therefore, the map for changing the acceleration correction coefficient Ka to be multiplied by the basic target acceleration a0 according to the duration Tt of the follow-up control is different between when traveling on the traveling lane and when traveling on the overtaking lane, as shown in FIG. It is assumed that the acceleration correction coefficient Ka is less likely to be smaller when traveling on the overtaking lane than when traveling on the traveling lane. According to such a configuration, when the own lane is the overtaking lane, a larger acceleration correction coefficient Ka is set than when the own lane is a traveling lane, and a larger target acceleration a is obtained.

  In the configuration of this modified example, the target acceleration a when the travel control shifts from the follow-up control to the constant speed control can be changed depending on the travel state of the host vehicle. It can be set larger during lane travel than during travel lane travel. For this reason, at the time of the transition from the follow-up control to the constant speed control, the own vehicle is accelerated at a greater acceleration when traveling in the overtaking lane than when traveling in the overtaking lane. The acceleration feeling given to the driver when driving on the lane is not impaired, and the followability to the target vehicle speed is prevented from being deteriorated.Therefore, the uncomfortable feeling given to the driver by the vehicle acceleration is reduced, and appropriate driving control is performed. Will be executed.

  FIG. 14 is a system configuration diagram of a vehicle travel control apparatus 100 mounted on a vehicle according to a third embodiment of the present invention. In FIG. 14, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted or simplified. FIG. 15 shows a flowchart of an example of a control routine executed by the control ECU 102 in the vehicle travel control apparatus 100 of this embodiment. The system of the present embodiment is a cruise control system that executes follow-up control and constant speed control as travel control, as in the first and second embodiments.

  As shown in FIG. 14, the vehicle travel control device 100 includes a control ECU 102 mainly composed of a computer. A cruise control switch 14, an inter-vehicle distance setting switch 16, a vehicle speed sensor 18, a navigation ECU 22, an illuminance sensor 28, a wiper switch 30, an accelerator pedal sensor 32, and a throttle actuator 34 are connected to the control ECU 102 and a radar sensor 104. Is connected. The radar sensor 104 is configured by, for example, a millimeter wave radar, a laser radar, a camera, or the like, and a signal corresponding to an obstacle (specifically, a preceding vehicle) existing within a predetermined range in front of the host vehicle is transmitted to the control ECU 102. Output for. The radar sensor 104 has a configuration capable of changing a predetermined range in which an obstacle is detected by a command from the control ECU 102.

  The control ECU 102 includes an ACC basic target acceleration 40, an ACC target acceleration correction coefficient calculation unit 42, an ACC target acceleration determination unit 44, and a throttle opening adjustment / calculation unit 46, and a radar sensor detection range setting unit 106. Have. The radar sensor detection range setting unit 106 is connected to the navigation ECU 22. The navigation ECU 22 supplies the radar sensor detection range setting unit 106 with data regarding the detected shape of the road in the traveling direction of the vehicle. The radar sensor detection range setting unit 106 detects the straight line distance of the road ahead of the host vehicle based on the data from the navigation ECU 22 as described in detail later, and the obstacle detection range by the radar sensor 104 based on the straight line distance. Set.

  Next, the operation of the vehicle travel control apparatus 100 of this embodiment will be described.

  In the present embodiment, the control ECU 102 first determines the road ahead of the host vehicle based on the shape data in the traveling direction of the road ahead of the host vehicle supplied from the navigation ECU 22 at the radar sensor detection range setting unit 106 at predetermined time intervals. The straight line distance Dstraight is detected (step 300). Then, it is determined whether or not the detected straight line distance Dstraight exceeds a predetermined reference distance Dstandard (step 302). The reference distance Dstandard is set to the distance to the farthest position in the normal detection range by the radar sensor 104.

  As a result, if it is determined that Dstraight> Dstandard is not established, the detection range by the radar sensor 104 is set to the normal detection range, that is, the reference distance Dstandard (step 304). On the other hand, if it is determined that Dstraight> Dstandard is established, the detection range by the radar sensor 104 is set to the smaller one of the detection linear distance Dstraight and the detectable limit distance Ddistant of the radar sensor 104 (step 306). .

  When the detection range set by the radar sensor 104 is set as described above, the radar sensor detection range setting unit 106 of the control ECU 102 supplies an output for instructing the detection range to the radar sensor 104 (step 308). In this case, the radar sensor 104 performs an obstacle detection process in the detection range in accordance with a command from the radar sensor detection range setting unit 106.

  Further, the control ECU 102 determines whether or not the execution conditions of the follow-up control and the constant speed control as the travel control are satisfied at every predetermined time (step 310). This condition is set when the cruise control switch 14 is in an on state allowing the execution of the traveling control by the operation of the vehicle driver, and the own vehicle speed based on the vehicle speed sensor 18 is within a region where the execution of the traveling control is permitted. To establish. As a result of the above determination, if the execution condition of the travel control is satisfied, the current vehicle speed at that time is set as the target vehicle speed to be traveled at a constant speed by the constant speed control, and thereafter the travel speed is The following processing is executed until control execution is canceled.

  The control ECU 12 takes in the target vehicle speed Va set as described above, and based on the output signal of the vehicle speed sensor 18, the state of the inter-vehicle distance setting switch 16, and the output signal of the radar sensor 104, the current vehicle speed V 0, An inter-vehicle distance setting value (target inter-vehicle distance) during follow-up control and information related to the preceding vehicle (specifically, the presence / absence, inter-vehicle distance, and relative speed) are fetched (step 312). Then, it is determined whether or not there is a preceding vehicle in the detection range on the own lane on the road in the traveling direction on which the own vehicle travels based on the information on the captured preceding vehicle (step 314).

  As a result of the determination, if there is no preceding vehicle within the detection range on the own lane, then the basic target acceleration a0 is set to the ACC basic in order to execute constant speed control for driving the own vehicle at the target vehicle speed Va. Calculation is performed at the target acceleration 40 (step 316). The calculation of the basic target acceleration a0 is performed with reference to the maps shown in FIGS. 2A to 2C in the first embodiment. On the other hand, when the preceding vehicle exists within the detection range on the own lane, the basic target acceleration a0 is calculated in the ACC basic target acceleration 40 in order to execute the follow-up control for causing the own vehicle to follow the preceding vehicle. (Step 318). The calculation of the basic target acceleration a0 is performed based on the deviation between the set target inter-vehicle distance during follow-up control and the actual inter-vehicle distance between the host vehicle and the preceding vehicle, and the relative speed between the host vehicle and the preceding vehicle. Is called.

  When the control ECU 12 calculates the basic target acceleration a0 as described above, the control ECU 12 multiplies the basic target acceleration a0 by the acceleration correction coefficient Ka calculated by the ACC target acceleration correction coefficient calculation unit 42, and the target to be the target of the host vehicle. The acceleration a is calculated by the ACC target acceleration determining unit 44. Then, the throttle opening adjusting / calculating unit 46 calculates the opening degree of the throttle valve based on the calculated target acceleration a (step 320), and the throttle actuator so that the throttle opening degree is realized. A drive command is issued to 34.

  When the above processing is repeated, follow-up control is executed when a preceding vehicle exists within the detection range on the own lane, and the vehicle speed of the preceding vehicle is higher than the vehicle speed of the own vehicle, so that the own vehicle is separated from the preceding vehicle. The host vehicle is accelerated to maintain the target inter-vehicle distance when it tends to leave, and after reaching the target inter-vehicle distance, it follows the preceding vehicle while maintaining the target inter-vehicle distance according to the vehicle speed change of the preceding vehicle Run. On the other hand, when there is no preceding vehicle in the detection range on the own lane due to, for example, a lane change of the preceding vehicle on the own lane during the follow-up control, the constant speed control is executed and the own vehicle speed V0 is higher than the target vehicle speed Va. When the vehicle speed is low, the host vehicle is accelerated toward the target vehicle speed Va, and after reaching the target vehicle speed Va, the vehicle travels while maintaining the target vehicle speed Va.

  Here, the detection range of the radar sensor 104 is usually a preceding vehicle on the own lane that travels in the same direction as the own vehicle on the guard lane, the oncoming vehicle, or the adjacent lane adjacent to the own lane on the road immediately before the curved road. In order to prevent erroneous detection, the range is limited to a range up to the detectable limit distance Ddistant, and is set to a narrow range up to the reference distance Dstandard in front of it. However, when the radar sensor 104 has a configuration that can be changed with respect to the detection range and the straight path is maintained long in front of the host vehicle, the detection range is limited to the detectable limit distance Ddistant, and the reference distance Even when setting to a wide range up to a distance longer than Dstandard, it is possible to detect the preceding vehicle at a relatively earlier timing than the normal time while avoiding erroneous detection of an obstacle.

  Therefore, in the vehicle travel control apparatus 100 of the present embodiment, the detection range by the radar sensor 104 is changed according to the linear distance of the road ahead of the host vehicle based on the detection data of the navigation ECU 22. Specifically, when the straight distance of the road in the traveling direction of the host vehicle is equal to or less than the reference distance Dstandard, the range up to the normal reference distance Dstandard is set with the limit of the detectable distance Ddistant of the radar sensor 104 as the limit. As the road straight line distance becomes longer than the reference distance Dstandard, the road distance increases beyond the reference distance Dstandard.

  According to such a configuration, when the host vehicle is going to travel on a road that has a long straight path in the future, the radar sensor 104 causes obstacles such as guardrails and oncoming vehicles other than the preceding vehicle existing on the host lane to While preventing erroneous detection as a preceding vehicle on the line, the radar sensor 104 can detect the preceding vehicle at a relatively earlier timing than normal.

  As described above, according to the vehicle travel control apparatus 100 of the present embodiment, when the host vehicle is traveling on a road that continues to be a straight road in the future, a preceding vehicle that is positioned relatively far away is controlled in the follow-up control. As a result, the tracking control that follows the preceding vehicle can be started earlier than usual, so that it is possible to execute the tracking control with gentle acceleration without large acceleration. It becomes. For this reason, it is possible to reduce the uncomfortable feeling given to the driver by the vehicle acceleration, and it is possible to execute appropriate traveling control.

  In the third embodiment described above, the control ECU 12 uses the radar sensor 104 to detect a preceding vehicle existing within a predetermined range in front of the host vehicle. "Running control means" described in the claims by executing the follow-up control detects the linear distance of the road in the traveling direction of the host vehicle based on the data from the navigation ECU 22. When the “road shape detection means” described in the range indicates the detection range by the radar sensor 104, the straight distance of the road in the traveling direction of the host vehicle is not more than the reference distance Dstandard, with the detectable limit distance Ddistant as the limit. Set the range up to the reference distance Dstandard, and the longer the road straight distance exceeds the reference distance Dstandard, the more the reference distance Dstandard exceeds The "preceding vehicle detection range changing means" described in the scope of claims is realized by expanding to far away.

  By the way, in the third embodiment, when the detected linear distance Dstraight of the road in the traveling direction of the host vehicle exceeds the reference distance Dstandard, the detection range by the radar sensor 104 is set as the detected linear distance Dstraight and the detectable limit distance Ddistant. However, the present invention is not limited to this, and is variable stepwise according to the detected linear distance Dstraight, with the detectable limit distance Ddistant as the limit. Also good.

  In the third embodiment, the basic target acceleration a0 is calculated based on the information on the preceding vehicle detected using the radar sensor 104 whose detection range is variable, and the basic target acceleration a0 is calculated as an acceleration correction coefficient. The target acceleration a to be the target of the host vehicle is calculated by multiplying Ka, and at this time, the acceleration correction coefficient Ka may be obtained by calculating as in the first or second embodiment described above. However, it may be obtained by calculation using another method or set to “1”.

  Further, in the first to third embodiments, the target to be controlled between the preceding vehicle and the target vehicle in the follow-up control for causing the own vehicle to follow the preceding vehicle and to be controlled between the own vehicle and the preceding vehicle. Although the inter-vehicle distance is used, the present invention is not limited to this, and may be a target inter-vehicle time between the host vehicle and the preceding vehicle. Even in such a configuration, it is possible to obtain the same effect as the above-described embodiment. The inter-vehicle time is calculated based on the inter-vehicle distance between the host vehicle and the preceding vehicle, the vehicle speed of the host vehicle, and the vehicle speed of the preceding vehicle, and is required until the host vehicle reaches the position of the preceding vehicle at the time of calculation. It is time, and the target inter-vehicle time is a target inter-vehicle time that must be taken until the host vehicle reaches the position of the preceding vehicle.

1 is a system configuration diagram of a vehicle travel control apparatus according to a first embodiment of the present invention. FIG. In the vehicle travel control apparatus of the present embodiment, it is a diagram showing a map used to calculate a basic target acceleration when the travel control is executed. It is a flowchart of an example of the control routine performed in the traveling control apparatus for vehicles of a present Example. FIG. 6 is a diagram showing a map used to correct a basic target acceleration a0 according to a set target inter-vehicle distance when executing the travel control in the vehicle travel control apparatus of the present embodiment. In the vehicle travel control apparatus of the present embodiment, it is a diagram showing a map used to correct the basic target acceleration a0 according to the lane position during travel when executing travel control. FIG. 6 is a diagram showing a map used for correcting the basic target acceleration a0 in accordance with the illuminance around the host vehicle when the travel control is executed in the vehicle travel control apparatus of the present embodiment. In the vehicle travel control apparatus of the present embodiment, it is a diagram showing a map used to correct the basic target acceleration a0 according to the operating state of the vehicle wiper when the travel control is executed. It is the figure which represented typically the condition where the target acceleration a calculated in the traveling control apparatus for vehicles which is 2nd Example of this invention changes with time. It is a flowchart of an example of the control routine performed in the traveling control apparatus for vehicles of a present Example. FIG. 6 is a diagram showing a map used to correct a basic target acceleration a0 at the time of control transition from follow-up control to constant speed control in the vehicle travel control apparatus of the present embodiment. FIG. 6 is a diagram showing a map used to correct a basic target acceleration a0 after the completion of control transition from follow-up control to constant speed control in the vehicle travel control apparatus of the present embodiment. In the vehicle travel control apparatus of this modification, it is the figure showing the map used for correct | amending the basic target acceleration a0 at the time of control transfer from follow-up control to constant speed control. In the vehicle travel control apparatus of this modification, it is a figure showing the map used for correct | amending basic target acceleration a0 after the completion of control transfer from follow-up control to constant speed control. It is a system configuration | structure figure of the vehicle travel control apparatus which is 3rd Example of this invention. It is a flowchart of an example of the control routine performed in the traveling control apparatus for vehicles of a present Example.

Explanation of symbols

10,100 Vehicle travel control device 12,102 Control ECU
22 Navigation ECU
28 Illuminance sensor 30 Wiper switch 34 Throttle actuator 104 Radar sensor a Target acceleration a0 Basic target acceleration Ka Acceleration correction coefficient

Claims (11)

A vehicle travel control device that executes travel control for accelerating the host vehicle at a target acceleration,
A traveling state detecting means for detecting the traveling state of the host vehicle;
Target acceleration changing means for changing the target acceleration in the running control according to the detection result of the running condition detecting means;
A vehicle travel control device comprising: The travel state detection means detects whether the lane in which the host vehicle travels is a travel lane or an overtaking lane adjacent to the travel lane,
The target acceleration changing means detects the travel when the traveling state detecting means detects that the lane in which the host vehicle is traveling is an overtaking lane, compared to when the traveling lane is detected. The vehicle travel control apparatus according to claim 1, wherein a target acceleration in the control is increased. The traveling state detection means detects the illuminance around the host vehicle,
2. The vehicle travel control apparatus according to claim 1, wherein the target acceleration changing means decreases the target acceleration in the travel control as the illuminance around the host vehicle is darker by the travel state detecting means. The traveling state detection means detects the operating state of the vehicle wiper,
2. The vehicle travel control device according to claim 1, wherein the target acceleration changing unit reduces the target acceleration in the travel control as the operating state of the vehicle wiper is a high speed operating state by the travel state detecting unit. .   The target acceleration in the travel control is that of the host vehicle that is required to make the inter-vehicle distance or inter-vehicle time between the host vehicle and the preceding vehicle coincide with the target inter-vehicle distance or the target inter-vehicle time when the host vehicle travels following the preceding vehicle. 5. The vehicle travel control device according to claim 1, wherein the vehicle travel control device is an acceleration or an acceleration of the host vehicle required when the host vehicle travels at a target vehicle speed. Runs the host vehicle at a constant speed at the target vehicle speed and, when there is a preceding vehicle ahead of the host vehicle, makes the host vehicle follow the preceding vehicle while maintaining the target inter-vehicle distance or target inter-vehicle time. A vehicular travel control device,
Follow-up travel duration measuring means for measuring the duration of follow-up travel to the preceding vehicle in the travel control;
Target acceleration changing means for changing the target acceleration in the case where the running control shifts from the follow-up running to the preceding vehicle to the constant speed running at the target vehicle speed according to the duration measured by the follow-up running duration measuring means. When,
A vehicle travel control device comprising:   7. The vehicle travel control apparatus according to claim 6, wherein the target acceleration changing means decreases the target acceleration as the duration time measured by the follow-up travel duration measurement means increases. A traveling state detecting means for detecting whether the lane in which the vehicle travels is a traveling lane or an overtaking lane adjacent to the traveling lane;
The target acceleration changing means is further configured such that when the traveling state detecting means detects that the lane on which the host vehicle is traveling is an overtaking lane, as compared with a case where it is detected that the lane is a traveling lane, The vehicle travel control apparatus according to claim 6 or 7, wherein the target acceleration is increased.   After acceleration of the host vehicle is started at the target acceleration by the target acceleration changing means by shifting the traveling control from the following traveling to the preceding vehicle to the constant speed traveling at the target vehicle speed, the target acceleration of the host vehicle is The vehicle travel control device according to any one of claims 6 to 8, further comprising acceleration increasing means for increasing from the target acceleration by the target acceleration changing means as time elapses. A preceding vehicle detecting means for detecting a preceding vehicle existing within a predetermined range ahead of the own vehicle; and a preceding vehicle existing within the predetermined range is detected by the preceding vehicle detecting means; A vehicle travel control device comprising: a travel control unit that performs a follow-up control that travels while maintaining a target inter-vehicle distance or a target inter-vehicle time,
Road shape detecting means for detecting straightness of the road shape in the traveling direction of the host vehicle;
Preceding vehicle detection range changing means for changing the predetermined range in which the preceding vehicle existing by the preceding vehicle detecting means should be detected according to the straightness of the road shape detected by the road shape detecting means;
A vehicle travel control device comprising:   The preceding vehicle detection range changing unit is configured to detect the preceding vehicle existing by the preceding vehicle detecting unit as compared with a case where the straightness of the road shape detected by the road shape detecting unit is high when compared to a low case. The vehicle travel control device according to claim 10, wherein the range is expanded.

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