JP2019077353A - Drive support apparatus - Google Patents

Abstract

To reduce travel energy and secure a high drivability in balance.SOLUTION: A drive support apparatus includes: a vehicle-itself speed obtainment part 11 for obtaining a vehicular speed Vof a vehicle itself 50; a preceding-vehicle information obtainment part 12 for obtaining an inter-vehicle distance Xand a relative speed (V-V) between the vehicle itself 50 and a preceding vehicle 60; a target inter-vehicle time setup part 13 for setting target inter-vehicle time T; a target brake-drive force computation part 14 for computing target brake-drive force Tfor causing the vehicle itself 50 to track the preceding vehicle 60; and a brake-drive control part 15 for controlling brake-drive force to be generated by the vehicle itself 50 so as to generate target brake-drive force Tin the vehicle itself 50. Further, the target brake-drive force computation part 14 computes target brake-drive force Ton the basis of the inter-vehicle distance X, relative speed (V-V), and travel resistance of the vehicle itself 50.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a driving support device.

  As a technology related to a conventional driving support device, for example, Patent Document 1 discloses a hybrid in which the engine is stopped and the motor travels when the speed of the vehicle is equal to or less than the engine stop setting speed when the vehicle travels following the forward vehicle. A vehicle operation control system is described. In the operation control system described in Patent Document 1, when the vehicle speed of the preceding vehicle is faster than the engine stop set speed and slower than the engine stop set speed plus the predetermined spare speed, the vehicle follow-up speed is set to the engine stop Set to speed and give priority to fuel efficiency improvement.

Unexamined-Japanese-Patent No. 2007-186069

  By the way, in the driving support apparatus as described above, the travel energy of the vehicle (energy required for traveling per unit distance) may be reduced by limiting the acceleration of the vehicle. In this case, the driver's intention of acceleration can not be sufficiently reflected in traveling, and drivability may be deteriorated.

  Then, this invention makes it a subject to provide the driving assistance apparatus which can make compatibility of reduction of driving energy, and ensuring of high drivability.

  The applicant filed Japanese Patent Application No. 2016-195642 as one means for solving the above-mentioned problems. In Japanese Patent Application No. 2016-195642, a target braking / driving force that causes the preceding vehicle to follow the host vehicle is calculated based on the inter-vehicle distance and the relative speed, and driving assistance of the host vehicle is performed based on the target braking / driving force. Thus, it is described that driving support can be realized which is compatible with the reduction of traveling energy and the securing of high drivability.

  As a result of further study on the above problems, the inventor of the present invention, even when the driving assistance is performed by the target braking / driving force calculated based on the inter-vehicle distance and the relative speed, drivability We have obtained the knowledge that there is a case that does not improve enough. The present invention is an invention made based on the knowledge.

  That is, the driving assistance apparatus according to the present invention includes a host vehicle speed acquisition unit for acquiring the vehicle speed of the host vehicle, a preceding vehicle information acquisition unit for acquiring an inter-vehicle distance and a relative speed between the host vehicle and the preceding vehicle, A target inter-vehicle time setting unit that sets the time, a target braking / driving force computing unit that calculates a target braking / driving force that causes the preceding vehicle to follow the own vehicle, and a target braking / driving force occurs in the vehicle The target braking / driving force computing unit computes a target braking / driving force based on the inter-vehicle distance, the relative speed, and the traveling resistance of the host vehicle.

  In the driving support device according to the present invention, the target braking / driving force is calculated based not only on the inter-vehicle distance and the relative speed but also on the traveling resistance of the own vehicle, so that the traveling energy is reduced even if the traveling resistance of the own vehicle changes. And ensuring high drivability.

  The target braking / driving force calculating unit may calculate the target braking / driving force based on the inter-vehicle distance and the relative speed, and may correct the calculated target braking / driving force based on the traveling resistance of the host vehicle. In this driving support device, the target braking / driving force calculated based on the inter-vehicle distance and the relative speed is corrected based on the traveling resistance of the vehicle, so the target braking / driving force according to the traveling resistance of the vehicle is easily calculated. can do.

  When the target braking / driving force is the target value of the driving force, the target braking / driving force calculation unit corrects the target braking / driving force more greatly as the traveling resistance of the host vehicle is larger, and the target braking / drive is performed as the traveling resistance of the host vehicle is smaller. The force may be corrected to a smaller value. In this driving support device, when the target braking / driving force is the target value of the driving force, the target braking / driving force is corrected to be larger as the traveling resistance of the host vehicle is larger, and the target braking / driving force is calculated as the traveling resistance of the host vehicle is smaller. In order to make the correction small, it is possible to appropriately calculate the target braking / driving force according to the traveling resistance of the host vehicle.

  The target braking / driving force computing unit may use the weight of the host vehicle as the travel resistance of the host vehicle. The traveling resistance of the vehicle changes depending on the weight of the vehicle. So, in this driving assistance device, the target braking / driving force according to the traveling resistance of the own vehicle can be appropriately calculated by using the weight of the own vehicle as the traveling resistance of the own vehicle.

  The target braking / driving force computing unit may use the slope of the road surface on which the host vehicle is traveling as the travel resistance of the host vehicle. The traveling resistance of the vehicle changes depending on the slope of the road surface on which the vehicle is traveling. Therefore, in this driving support device, it is possible to appropriately calculate the target braking / driving force according to the traveling resistance of the own vehicle by using the gradient of the road surface on which the own vehicle is traveling as the traveling resistance of the own vehicle.

  According to the present invention, it is possible to provide a driving support device capable of achieving both reduction of traveling energy and securing of high drivability.

It is a figure showing composition of a driving assistance device concerning an embodiment. It is a figure which shows the relationship between the own vehicle and a preceding vehicle. It is the schematic of a driving energy reduction driving | operation model. It is a block diagram showing driving support control of a driving support device. It is a figure which shows the relationship between weight, a gradient, and a correction coefficient. It is a flowchart which shows control operation of a driving assistance device.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals and redundant description will be omitted.

  FIG. 1 is a diagram showing a configuration of a driving support device according to the embodiment. FIG. 2 is a diagram showing the relationship between the host vehicle and the preceding vehicle. As shown in FIGS. 1 and 2, the driving support device 100 is mounted on the host vehicle 50. The host vehicle 50 is not particularly limited, and may be, for example, any of a large vehicle, a medium vehicle, a passenger car, a small vehicle, and a light vehicle. In addition, the host vehicle 50 may be any of a hybrid vehicle, an engine vehicle, an electric vehicle, a fuel cell vehicle, and the like.

The driving support device 100 supports the driving of the host vehicle 50 so as to follow the preceding vehicle 60 actually traveling in front of the host vehicle 50. The driving support device 100 includes a vehicle speed sensor 1, a periphery monitoring sensor 2, a running resistance acquisition unit 3, a braking / driving force generating device 4, and an ECU (Electronic Control Unit) 10. In the following, V _f will be described as the vehicle speed of the _host vehicle 50, X _dist as the inter-vehicle distance to the leading vehicle 60, and V _p as the vehicle speed of the leading vehicle 60.

The vehicle speed sensor 1 is a detector that detects the vehicle speed V _f of the host vehicle 50. As the vehicle speed sensor 1, for example, a wheel speed sensor that is provided to a wheel of the vehicle 50 or a drive shaft that rotates integrally with the wheel or the like and that detects the rotational speed of the wheel is used. The vehicle speed sensor 1 transmits the detected vehicle speed information to the ECU 10.

  The surrounding area monitoring sensor 2 is a detection device that detects the surrounding information of the host vehicle 50. The perimeter monitoring sensor 2 includes at least one of a camera, a radar, and a laser radar. The camera is an imaging device for imaging peripheral information of the host vehicle 50. The camera is provided, for example, on the back side of the windshield of the host vehicle 50. The camera transmits the imaging information to the ECU 10 as peripheral information. The camera may be a monocular camera or a stereo camera. The radar detects an obstacle outside the host vehicle 50 using radio waves (for example, millimeter waves). The radar transmits radio waves around the host vehicle 50, and detects an obstacle by receiving the radio wave reflected by the obstacle. The radar transmits the detected obstacle information to the ECU 10 as peripheral information. The laser radar detects an obstacle outside the host vehicle 50 using light. The laser radar emits light to the surroundings of the host vehicle 50, receives the light reflected by the obstacle, measures the distance to the reflection point, and detects the obstacle. The laser radar transmits the detected obstacle information to the ECU 10 as peripheral information. Note that cameras, riders and radars as the surroundings monitoring sensor 2 do not necessarily have to be redundantly provided.

  The traveling resistance acquisition unit 3 acquires the traveling resistance of the host vehicle 50. The running resistance is a function to inhibit the running of the vehicle, and varies depending on, for example, the weight of the vehicle, the gradient of the running path on which the vehicle is running, and the like. In the present embodiment, the traveling resistance acquisition unit 3 acquires, as traveling resistance of the host vehicle 50, the weight of the host vehicle 50 and the gradient of the traveling path on which the host vehicle 50 is traveling. The weight of the host vehicle 50 can be obtained, for example, by the estimation method described in JP-A-2016-217851. The slope of the traveling path on which the vehicle 50 is traveling can be determined, for example, from the detection value of the G sensor and the detection value of the acceleration sensor. Then, the traveling resistance acquisition unit 3 transmits the acquired traveling resistance of the host vehicle 50 to the ECU 10.

  The braking / driving force generating device 4 is a device that causes the vehicle 50 to generate a driving force and / or a braking force. The braking / driving force generating device 4 causes the host vehicle 50 to generate a driving force when the driver operates the accelerator pedal. The braking / driving force generating device 4 causes the vehicle 50 to generate a braking force when the driver releases the accelerator pedal and / or the driver operates the brake pedal.

  When the host vehicle 50 is a vehicle having only an engine as a drive source, examples of the braking / driving force generator 4 that generates a driving force include an engine such as a diesel engine or a gasoline engine. When the host vehicle 50 is a hybrid vehicle having an engine and a motor as a drive source, it functions as an engine such as a diesel engine or a gasoline engine and a motor generator as the braking / driving force generating device 4 that generates the driving force. And a motor. In these cases, when the driver operates the accelerator pedal, the engine and / or the motor is driven to generate a driving force in the host vehicle 50.

  When the host vehicle 50 is a vehicle having only the engine as a drive source, examples of the braking / driving force generating device 4 that generates the braking force include a service brake, a retarder, an engine brake, and the like. When the host vehicle 50 is a hybrid vehicle having an engine and a motor as a drive source, the braking / driving force generator 4 for generating a braking force may be, for example, a service brake, a retarder, an engine brake, a motor functioning as a motor generator, etc. Can be mentioned. In this case, when the driver releases the accelerator pedal, an engine brake is generated and a braking force is generated in the host vehicle 50. In addition, when the driver operates the brake pedal, the service brake and / or the retarder is actuated to generate a braking force in the host vehicle 50. In addition, when the driver operates the brake pedal, regenerative torque is generated in the motor, and a braking force is generated in the host vehicle 50.

  The ECU 10 is an electronic control unit having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like. The ECU 10 loads a program stored in the ROM into the RAM and executes the program by the CPU to execute various controls. The ECU 10 may be configured of a plurality of electronic control units.

  The ECU 10 includes a host vehicle speed acquisition unit 11, a preceding vehicle information acquisition unit 12, a target inter-vehicle time setting unit 13, a target braking / driving force computing unit 14, and a braking / driving control unit 15.

The own vehicle speed acquisition unit 11 acquires the vehicle speed V _f of the own vehicle 50 from the vehicle speed information transmitted from the vehicle speed sensor 1.

The preceding vehicle information acquisition unit 12 acquires an inter-vehicle distance X _dist between the host vehicle 50 and the preceding vehicle 60 and a relative velocity (V _p −V _f ) from the surrounding information transmitted from the surrounding area monitoring sensor 2. The leading vehicle information acquisition unit 12 first recognizes the leading vehicle 60 based on the surrounding information of the surroundings monitoring sensor 2. When the preceding vehicle information acquiring unit 12 recognizes the preceding vehicle 60, the preceding vehicle information acquiring unit 12 acquires the inter-vehicle distance X _dist from the preceding vehicle 60 based on the surrounding information of the surrounding area monitoring sensor 2. Further, the leading vehicle information acquisition unit 12 acquires a differential value of the inter-vehicle distance X _dist as a relative velocity (V _p −V _f ) with respect to the leading vehicle 60. The preceding vehicle information acquisition unit 12 may acquire the inter-vehicle distance X _dist and the relative speed (V _p −V _f ) between the host vehicle 50 and the preceding vehicle 60 by another method. For example, preceding vehicle information acquisition section 12, by obtains the vehicle speed V _p of the preceding vehicle 60 from the peripheral monitoring sensor 2 is subtracted from the vehicle speed V _p of the preceding vehicle 60 to the vehicle speed V _f of the vehicle 50, the relative velocity (V You may acquire _p - _Vf ).

The target inter-vehicle time setting unit 13 sets a target inter-vehicle time T _hw . The target inter-vehicle time T _hw is a target time until the _host vehicle 50 reaches the current position of the preceding vehicle 60, and is an arbitrarily set time. The target inter-vehicle time T _hw may be set by a manual operation by the driver, or may be automatically set by the target inter-vehicle time setting unit 13.

The target braking / driving force computing unit 14 computes a target braking / driving force T _{opt — ref} that causes the preceding vehicle 60 to follow the _host vehicle 50. The target braking / driving force T _{opt — ref} is a target driving force (torque) or a target braking force (torque) that causes the preceding vehicle 60 to follow the _host vehicle 50 so as to realize the driving energy reduction driving. Then, the target braking / driving force calculation unit 14 calculates the target braking / driving force T _{opt — ref} based on the inter-vehicle distance X _dist , the relative speed (V _p −V _f ), and the traveling resistance of the _host vehicle 50.

  The traveling energy reduction driving is a driving to reduce the energy [Wh / km] required for traveling per unit distance. Driving energy reduction driving is also referred to as fuel saving driving. The driving energy reduction driving does not use acceleration as a control amount, but uses the vehicle speed as a control amount, and aims to realize a driving operation that does not decelerate as much as possible (that is, a driving operation that does not discard the input energy).

  FIG. 3 is a schematic view of a driving energy reduction driving model. As shown in FIG. 3, the driving energy reduction driving following the leading vehicle 60 can be expressed using a spring damping system model 6 having a spring 6 a and a damper 6 b between the leading vehicle 60 and the driving energy reduction driving. Such driving energy reduction driving has a characteristic of decelerating so that the relative speed decreases as approaching the preceding vehicle 60 rather than the target inter-vehicle distance. In other words, the driving energy reduction driving of this embodiment has a characteristic that the change in vehicle speed becomes insensitive due to the action of the spring 6a and the damper 6b, and it becomes difficult for the preceding vehicle 60 to approach and move further away.

By the way, as shown in FIG. 2, when the driver performs a driving operation of the own vehicle 50 so as to make the following vehicle 60 follow, the inter-vehicle distance X _dist with the preceding vehicle 60 and the relative velocity (V _p −V _f ), The target braking / driving force T _{drv_ref} of the _host vehicle 50 is determined, and acceleration / deceleration operation of the _host vehicle 50 is performed. As acceleration-deceleration operation of the own vehicle 50, operation of an accelerator pedal, cancellation | release of an accelerator pedal, operation of a brake pedal etc. are mentioned, for example. When the driver formulates the determination for determining the target braking / driving force T _{drv_ref} , the following equation (1) is obtained. However, due to the constraint condition of the braking / driving force generation device 4, the target braking / driving force T _{drv_ref} of the driver is given by the following equation (2).

T _{drv_ref} = {G X _ _drv (X _dist- T _hw · V _f ) + G V _{_ drv} (V _p- V _f )} H (s) (1)
T _{ref_min} <T _{drv_ref} <T _{ref_max} (2)
G _{X drv} is an inter-vehicle distance gain with respect to an inter-vehicle distance X _dist from the leading vehicle 60, and represents a driver's driving characteristic. G _{V — drv} is a relative speed gain with respect to the relative speed (V _p −V _f ) with the preceding vehicle 60, and represents a driver's driving characteristic. T _hw · V _f is a target inter-vehicle distance obtained by multiplying the target inter-vehicle time T _hw by the vehicle speed V _f . In other words, the target inter-vehicle distance is calculated by multiplying the target inter-vehicle time T _hw by the vehicle speed V _f . H (s) is a hysteresis characteristic such as the reaction delay of the driver, the reaction time of the muscle and the like. T _{ref — max} is a drive torque corresponding to the acceleration performance of the braking / driving force generator 4, and corresponds to, for example, the maximum output torque on the drive side of the braking / driving force generator 4. T _{ref — min} is a braking torque corresponding to the deceleration performance of the braking / driving force generator 4, and corresponds to, for example, the maximum output torque on the braking side of the braking / driving force generator 4.

Therefore, the target braking / driving force calculation unit 14 obtains the target braking / driving force T _{opt_ref} as shown in FIG. 4 according to the determination for the _driver to determine the target braking / driving force T _{drv_ref} . FIG. 4 is a block diagram showing driving support control of the driving support device. In FIG. 4, the block diagram enclosed by D corresponds to the above equation (1), and models the judgment of the driver rather than the driving support control of the driving support device 100. The target braking / driving force calculation unit 14 has a component obtained by multiplying the difference between the inter-vehicle distance X _dist and the target inter-vehicle distance (T _hw · V _F ) by the inter-vehicle distance gain G _X as shown in the following equation (3) A target braking / driving force T _{opt — ref} is obtained based on a component obtained by multiplying the relative velocity gain G _V by the relative velocity (V _p −V _f ). However, due to the constraint condition of the braking / driving force generating device 4, the target braking / driving force T _{opt — ref} is set to the following equation (4).

T _opt — _ref = G _X (X _{dist −} T _hw · V _f ) + G _V (V _{p −} V _f ) (3)
T _{ref_min} <T _{opt_ref} <T _{ref_max} (4)
G _X is an inter-vehicle distance gain with respect to the inter-vehicle distance X _dist from the leading vehicle 60. G _V is a relative velocity gain with respect to the relative velocity with the leading vehicle 60.

The braking / driving control unit 15 controls the braking / driving force generated by the vehicle 50 so that the target braking / driving force T _{opt — ref} is generated in the vehicle 50. Specifically, the braking / driving control unit 15 first compares the actual braking / driving force generated by the driver's acceleration / deceleration operation with the target braking / driving force T _{opt — ref} .

Then, when the actual driving force is larger than the target driving force T _{opt_ref} , the driving control unit 15 controls the braking / driving force generation device 4 so that the actual driving force becomes the target braking force T _{opt_ref.} A braking force is generated in the host vehicle 50. For example, the braking / driving control unit 15 corrects (overwrites) the brake pedal operation amount so as to activate the service brake and / or the retarder such that the actual braking / driving force becomes the target braking / driving force T _{opt — ref} . Further, the braking / driving control unit 15 corrects (overwrites) the accelerator pedal operation amount so that the actual braking / driving force becomes the target braking / driving force T _{opt — ref,} and generates an engine brake. Further, the braking / driving control unit 15 corrects (overwrites) the accelerator pedal operation amount so that the actual braking / driving force becomes the target braking / driving force T _{opt — ref,} and _causes the motor to generate regenerative torque.

On the other hand, when the actual driving force is smaller than the target driving force T _{opt_ref} , the driving control unit 15 controls the driving force generating device 4 so that the actual driving force becomes the target driving force T _{opt_ref.} The driving force is generated in the host vehicle 50. For example, the braking / driving control unit 15 corrects (overwrites) the operation amount of the accelerator pedal so that the actual braking / driving force becomes the target braking / driving force T _{opt — ref} and drives the engine and / or the motor.

  By the way, when making a vehicle run steadily, a big driving force is needed, so that traveling resistance of a vehicle becomes large. That is, the traveling resistance increases as the weight of the vehicle increases, and the traveling resistance decreases as the weight of the vehicle decreases. In addition, the travel resistance increases as the uphill slope of the travel path increases, and the travel resistance decreases as the downhill slope of the travel path increases. For this reason, for example, in order to make the vehicle travel at the same vehicle speed with different travel resistances, it is necessary to change the driving force of the vehicle between these states. In other words, it is necessary to make the driving force (for example, the accelerator opening degree) of a vehicle having a large running resistance greater than the driving force of a vehicle having a small running resistance.

Here, it is assumed that the leading vehicle 60 and the host vehicle 50 are steady traveling at the same vehicle speed (V _p = V _f ). In this case, since the term of G _V (V _p −V _f ) is 0 in the above equation (3), T _opt — _ref = G _X (X _dist −T _hw · V _f ). Since the inter-vehicle distance gain _{G X} and the target inter-vehicle time _{T hw} is a fixed value, the target braking-driving force _{T Opt_ref} is a function in which only following distance _{X dist} variable. That is, the target braking / driving force T _{opt — ref} can be changed only by the inter-vehicle distance X _dist . In other words, the target braking / driving force T _{opt — ref} can not be changed unless the inter-vehicle distance X _dist changes. Therefore, for example, even if the driver depresses the accelerator, the actual driving force does not increase until the inter-vehicle distance X _dist increases. In addition, even if the driver releases the accelerator, the actual driving force does not decrease until the inter-vehicle distance X _dist decreases.

Therefore, even if the driving resistance of the _host vehicle 50 is large even if the driving support of the _host vehicle 50 is performed based on the target braking / driving force T _{opt_ref} calculated by the above equation (3), In some cases, an appropriate driving force may not be obtained in order to cause the vehicle to travel at the same vehicle speed as the preceding vehicle 60. In addition, if the traveling resistance of the host vehicle 50 is small or if the traveling resistance of the host vehicle 50 is reduced, an appropriate braking force may not be obtained in order to cause the host vehicle 50 to travel at the same vehicle speed. As a result, drivability may be degraded. For example, considering that the host vehicle 50 follows the leading vehicle 60 and enters the ascending slope road from the flat road, immediately after the host vehicle 50 enters the ascending slope road, even if the driver depresses the accelerator, Since the inter-vehicle distance _Xdist does not change, the vehicle speed _Vf of the host vehicle 50 decreases. Then, when the inter-vehicle distance X _dist to the preceding vehicle 60 increases with the decrease of the vehicle speed V _f of the own vehicle 50, the target braking / driving force T _{opt_ref} becomes large and the vehicle speed V _f of the own vehicle 50 increases. The distance between the vehicle and X _dist decreases.

Therefore, the target braking / driving force computing unit 14 computes the target braking / driving force T _{opt — ref} also based on the traveling resistance of the _host vehicle 50. That is, the target braking / driving force computing unit 14 computes the target braking / driving force _{Topt_ref according} to the above equation (3), and _{corrects the} computed target braking / driving force _{Tot_ref} based on the traveling resistance of the _host vehicle 50.

Specifically, the target braking / driving force calculation unit 14 multiplies the target braking / driving force T _{opt — ref} calculated by the above equation (3) by the correction coefficient corresponding to the traveling resistance of the _host vehicle 50 to obtain the above equation. The target braking / driving force T _{opt — ref} calculated in (3) is corrected based on the traveling resistance of the vehicle 50. The correction coefficient can be, for example, a coefficient based on one. When the target braking / driving force T _{opt — ref} is the target value of the driving force, the correction coefficient increases as the traveling resistance of the _host vehicle 50 increases, and decreases as the traveling resistance of the _host vehicle 50 decreases. For example, as shown in FIG. 5, as the weight of the host vehicle 50 increases, the correction coefficient increases, and as the weight of the host vehicle 50 decreases, the correction coefficient decreases. Further, the correction coefficient becomes larger as the upslope of the traveling road becomes larger, and the correction coefficient becomes smaller as the downslope of the traveling road becomes larger. On the other hand, when the target braking / driving force T _{opt — ref} is the target value of the braking force, the correction coefficient increases as the weight of the _host vehicle 50 increases, and decreases as the downward inclination of the _host vehicle 50 increases.

It is preferable that the target braking / driving force computing unit 14 prepare in advance a correction map in which the traveling resistance of the host vehicle 50 and the correction coefficient correspond to each other. In this case, the target braking / driving force calculating unit 14 acquires the correction coefficient corresponding to the traveling resistance of the vehicle 50 from the correction map, and calculates the target braking / driving force calculated by the above equation (3). _Multiply T _{opt_ref} . The correction map can be determined, for example, as follows. First, a reference running resistance is set as a reference running resistance, and a correction coefficient corresponding to the reference running resistance is set as 1. And a correction coefficient is calculated so that the same vehicle speed as reference driving resistance can be obtained in various driving resistances. If the correction coefficient registered in the correction map does not have a correction coefficient corresponding to the traveling resistance, the correction coefficient corresponding to the traveling resistance may be determined by linearly interpolating the correction coefficient registered in the correction map. Good.

  Next, the processing operation of the driving support device 100 will be described.

As shown in FIG. 6, first, the driving assistance apparatus 100 acquires the vehicle speed V _f of the host vehicle 50, and the inter-vehicle distance X _dist between the host vehicle 50 and the preceding vehicle 60 and the relative vehicle speed (V _p- V _f ). Is acquired (step S1). Next, the driving assistance apparatus 100 sets a target inter-vehicle time T _hw (step S2). Note that steps S1 and S2 may be performed in reverse or simultaneously. Next, the driving support apparatus 100 calculates the target braking / driving force T _{opt — ref} based on the equation (3) (step S3).

Next, the driving support apparatus 100 _{corrects the} target braking / driving force T _{opt — ref} calculated in step S3 based on the traveling resistance of the _host vehicle 50 (step S4). That is, the target braking / driving force calculation unit 14 acquires a correction coefficient corresponding to the traveling resistance of the vehicle 50 from the correction map, and multiplies the _acquired target by the acquired correction coefficient by the target braking / driving force T _{opt — ref} calculated in step S3.

Next, the driving support apparatus 100 _{limits the} target braking / driving force T _{opt — ref} corrected in step S4 within the effective range of equation (4) (step S5). That is, when the target braking-driving force _{T Opt_ref} is less than _{T Ref_min is} a _{T Ref_min} above, the target braking-driving force _{T Opt_ref} is the greater than _{T Ref_max,} the following _{T ref_max.} For example, when the target braking / driving force T _{opt_ref} is less than T _{ref_min} , the target braking / driving force T _{opt_ref} is T _{ref_min,} and when the target braking / driving force T _{opt_ref} is larger than T _{ref_max} , the target braking / driving force T _{opt_ref} is T _{It is referred} to as _{ref_max} .

Next, the driving support apparatus 100 _{causes the host} vehicle 50 to generate the target braking / driving force T _{opt_ref} corrected at step S4 (or limited at step S5). Control is performed (step S6).

As described above, in the driving support device 100 according to the present embodiment, the target braking / driving force T is based not only on the inter-vehicle distance X _dist and the relative speed (V _p- V _f ) but also on the traveling resistance of the own vehicle 50. _{Since the opt_ref} is calculated, it is possible to achieve both the reduction of the traveling energy and the securing of high drivability even if the traveling resistance of the _host vehicle 50 changes.

Further, in order to correct the target braking / driving force T _{opt — ref} calculated based on the inter-vehicle distance X _dist and the relative speed (V _p −V _f ) based on the traveling resistance of the own vehicle 50, The target braking / driving force T _{opt — ref} can be easily calculated.

Further, when the target braking / driving force T _{opt_ref} is the target value of the driving force, the target braking / driving force T _{opt_ref} is corrected to be larger as the traveling resistance of the vehicle 50 is larger, and the target braking / driving is as the traveling resistance of the vehicle 50 is smaller Since the force T _{opt — ref} is corrected to be small, it is possible to appropriately calculate the target braking / driving force T _{opt — ref} according to the traveling resistance of the _host vehicle 50.

Further, by using the weight of the vehicle 50 and the gradient of the road surface on which the vehicle 50 is traveling as the traveling resistance of the vehicle 50, the target braking / driving force T _{opt_ref} according to the traveling resistance of the vehicle 50 is appropriately calculated. can do.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the scope of the invention as set forth in the claims. May be

For example, in the above embodiment, the calculated target braking-driving force T _{Opt_ref} have been described as being corrected based on the running resistance of the vehicle 50, using the inter-vehicle distance gain G _X corresponding to the running resistance of the vehicle 50 may calculate the target braking-driving force _{T opt_ref,} may be multiplied by the correction coefficient corresponding to the running resistance of the vehicle 50 to the vehicle distance gain _{G X} calculates the target braking-driving force _{T opt_ref.}

  In the above embodiment, both of the weight of the vehicle 50 and the gradient of the traveling road on which the vehicle 50 is traveling are used as the traveling resistance of the vehicle 50. However, only one of them is used. However, other running resistances may be used.

In the above embodiment, although the target braking / driving force T _{opt_ref} is calculated based on the equation (1), the target braking / driving force T _{opt_ref} is also calculated based on components other than the equation (1). It is good also as things.

In the above embodiment, although the inter-vehicle distance gain G _X and the relative velocity gain G _V been described as a constant value, the inter-vehicle distance gain G _X and the relative velocity gain G _V may be variable.

Further, in the above embodiment, although the braking / driving force is used as the control target, the driving force or the accelerator opening may be used as the control target. In this case, the target driving force which is the target value of the driving force or the target accelerator opening degree which is the target value of the accelerator opening is calculated instead of the target braking / driving force T _{opt — ref} , and the calculated target driving force or target accelerator opening is calculated. The driving force or the accelerator opening degree of the host vehicle 50 may be controlled based on the degree. In these cases, the braking / driving force and the target braking / driving force described in the above embodiment may be simply replaced with the driving force and the target driving force, or the accelerator opening degree and the target accelerator opening degree.

  DESCRIPTION OF SYMBOLS 1 ... vehicle speed sensor, 2 ... periphery surveillance sensor, 3 ... running resistance acquisition part, 4 ... braking / driving force generating device, 6 ... spring damping system model, 6 a ... spring, 6 b ... damper, 10 ... ECU, 11 ... own vehicle speed acquisition Part 12 12 leading vehicle information acquisition part 13 target inter-vehicle time setting part 14 target braking / driving force computing part 15 braking / driving control part 50 self-vehicle 60 leading vehicle 100 driving assistance device.

Claims (5)

A host vehicle speed acquisition unit for acquiring the host vehicle speed;
A preceding vehicle information acquisition unit that acquires an inter-vehicle distance and a relative speed between the host vehicle and the preceding vehicle;
A target inter-vehicle time setting unit for setting a target inter-vehicle time;
A target braking / driving force computing unit that computes a target braking / driving force that causes the preceding vehicle to follow the preceding vehicle;
And a braking / driving control unit that controls the braking / driving force generated by the vehicle so that the target braking / driving force is generated in the vehicle.
The target braking / driving force computing unit computes the target braking / driving force based on the inter-vehicle distance, the relative speed, and the traveling resistance of the host vehicle.
Driving support device. The target braking / driving force computing unit computes the target braking / driving force based on the inter-vehicle distance and the relative speed, and corrects the computed target braking / driving force based on the traveling resistance of the host vehicle.
The driving support device according to claim 1. When the target braking / driving force is the target value of the driving force, the target braking / driving force calculating unit corrects the target braking / driving force more as the traveling resistance of the host vehicle is larger, and the traveling resistance of the host vehicle is The smaller the target braking / driving force is corrected to be smaller,
The driving support device according to claim 2. The target braking / driving force computing unit uses the weight of the host vehicle as a travel resistance of the host vehicle.
The driving support device according to any one of claims 1 to 3. The target braking / driving force computing unit uses the slope of the road surface on which the vehicle is traveling as the travel resistance of the vehicle.
The driving assistance device according to any one of claims 1 to 4.

Images