JP2009090810A - Travel control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a travel control device for a vehicle capable of changing a vehicle speed fluctuation allowable range to an optimum range. <P>SOLUTION: The travel control device for the vehicle is provided with a vehicle speed sensor 11 for detecting a vehicle speed, a returning/accelerating switch 13 and a setting/decelerating switch 14 for setting a target vehicle speed, a vehicle speed fluctuation allowable range setting means for setting the vehicle speed fluctuation allowable range including the target vehicle speed set by the target vehicle speed setting means, an instructed vehicle speed calculating means for calculating an instructed vehicle speed in the vehicle speed fluctuation allowable range, a throttle opening control part 36 for controlling travel of the vehicle based on the instructed vehicle speed, and an upper limit vehicle speed changing switch 19 and a lower limit vehicle speed changing switch 20 for changing the vehicle speed fluctuation allowable range by operation of an occupant. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle travel control device.

  As a vehicle travel control device, the set vehicle speed set by the driver is compared with the actual vehicle speed, and a cruise control system that performs constant speed traveling by performing acceleration / deceleration control of the vehicle so that the actual vehicle speed matches the set vehicle speed ( (Hereinafter abbreviated as CC), or when a preceding vehicle is detected, the vehicle follows the preceding vehicle while maintaining a predetermined inter-vehicle distance. When no preceding vehicle is detected, the vehicle is set at the set vehicle speed set by the driver. An adaptive cruise control system (hereinafter abbreviated as ACC) that performs high-speed traveling is known. Also, there are some which improve the fuel efficiency by enabling the cylinder deactivation operation of the internal combustion engine in CC or ACC (see, for example, Patent Document 1). In these CC and ACC, a vehicle speed fluctuation allowable range is set for the set vehicle speed, and the traveling speed of the host vehicle is controlled within this vehicle speed fluctuation allowable range.

In recent years, a target fuel consumption driving apparatus has been developed that compares the target fuel consumption set by the driver with the actual fuel consumption and performs acceleration / deceleration control and constant speed running control so that the actual fuel consumption approaches the target fuel consumption. In this target fuel efficiency driving device, a vehicle speed fluctuation allowable range is set with respect to a target speed set by the driver, and the traveling speed of the host vehicle is controlled within this vehicle speed fluctuation allowable range.
JP 2004-340061 A

  However, in the conventional CC and ACC, the upper limit of the vehicle speed fluctuation allowable range is fixed to the set vehicle speed as shown in FIG. 8, and the vehicle speed cannot be made higher than the set vehicle speed. Further, the lower limit of the vehicle speed fluctuation allowable range was a uniform fixed value regardless of the set vehicle speed. Also in the target fuel efficiency driving apparatus, the upper limit of the vehicle speed fluctuation allowable range is fixed to the target vehicle speed, and the vehicle speed cannot be made larger than the target vehicle speed, and the lower limit is a fixed value that is uniform regardless of the target vehicle speed. As described above, the conventional CC and ACC and the target fuel efficiency driving apparatus in which the vehicle speed fluctuation allowable range is set have the following problems.

  For example, when there is a vehicle (accompanying vehicle) that accompanies the host vehicle and only the host vehicle is traveling by the CC or ACC, the host vehicle and the accompanying vehicle are traveling at a vehicle speed close to the set vehicle speed. In addition, when only the host vehicle automatically decelerates following other slow preceding vehicles, or when only the host vehicle is running with the target fuel efficiency driving device, the host vehicle has decelerated to reduce fuel consumption. In some cases, even if the vehicle subsequently returns to the target vehicle speed, the vehicle may decelerate once and a speed difference from the accompanying vehicle may occur, resulting in an increase in the distance from the accompanying vehicle. This can also occur when the driver decelerates by operating the brake pedal while traveling by CC or ACC, and then returns to the set vehicle speed by a subsequent return operation.

  Even if there is a driver's request to automatically regain the delay later when the delay occurs with respect to the accompanying vehicle, the conventional CC and ACC and the target fuel efficiency driving device can change the vehicle speed. Since the upper limit of the allowable range is fixed at the set vehicle speed or the target vehicle speed, the vehicle speed cannot be automatically increased to an area that exceeds the set vehicle speed or the target vehicle speed, and it is difficult to automatically recover the delay caused by the deceleration. There was something wrong. Therefore, for example, when the accompanying vehicle is traveling at a constant speed and the host vehicle is traveling by CC, ACC, or the target fuel consumption driving device, depending on the frequency of deceleration of the host vehicle, the vehicle can gradually be moved to the accompanying vehicle. There was a problem.

In addition, when traveling with the target fuel efficiency driving device, if the vehicle speed is reduced to a vehicle speed that is very slow relative to the flow of the surrounding vehicles in order to reduce fuel consumption, the lower limit of the vehicle speed fluctuation allowable range is a fixed value. As shown in FIG. 9, there are cases where the vehicle speed may drop below the driver's preferred vehicle speed, or may drop to a vehicle speed that does not follow the flow of surrounding vehicles. It was.
Therefore, the present invention provides a vehicular travel control device that can change the allowable range of vehicle speed fluctuations to an optimum range.

The vehicle travel control apparatus according to the present invention employs the following means in order to solve the above problems.
The invention according to claim 1 includes a vehicle speed sensor (for example, a vehicle speed sensor 11 in an embodiment described later) for detecting the vehicle speed and target vehicle speed setting means for setting a target vehicle speed (for example, a return / acceleration switch 13 in the embodiment described later). , A set / deceleration switch 14), vehicle speed fluctuation allowable range setting means for setting a vehicle speed fluctuation allowable range including the target vehicle speed set by the target vehicle speed setting means (for example, FI-ECU 30 in the embodiment described later), Instruction vehicle speed calculation means (for example, FI-ECU 30 in the embodiment described later) for calculating the instruction vehicle speed within the vehicle speed fluctuation allowable range, and travel control means (for example, implementation described later) for performing vehicle travel control based on the instruction vehicle speed. In the vehicle travel control device comprising the throttle opening control unit 36) in the example, the vehicle speed is controlled by the operation of the passenger Vehicle speed fluctuation allowable range changing means for changing the dynamic allowable range (for example, a return / acceleration switch 13, a set / deceleration switch 14, an upper limit vehicle speed change switch 19 and a lower limit vehicle speed change switch 20 in an embodiment described later) is provided. And
With this configuration, when the host vehicle is travel controlled within the vehicle speed fluctuation allowable range including the target vehicle speed, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's will.

According to a second aspect of the present invention, in the first aspect of the invention, the vehicle speed fluctuation allowable range changing means adds an upper limit set value set by an occupant's operation to the target vehicle speed. The upper limit is changed.
With this configuration, the upper limit of the vehicle speed fluctuation allowable range can be changed to a value larger than the target vehicle speed.

According to a third aspect of the present invention, in the first or second aspect of the invention, the vehicle speed fluctuation allowable range changing means subtracts a lower limit set value set by an occupant's operation from the target vehicle speed. The lower limit of the fluctuation allowable range is changed.
With this configuration, the lower limit of the vehicle speed fluctuation allowable range can be changed to a value smaller than the target vehicle speed.

The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein an actual fuel consumption calculation means for calculating an actual fuel consumption (for example, an actual fuel consumption calculation means 31 in an embodiment described later); The target fuel consumption setting means for setting the target fuel consumption (for example, the target fuel consumption changeover switch 18 in an embodiment described later), the actual fuel consumption calculated by the actual fuel consumption calculation means, and the target fuel consumption set by the target fuel consumption setting means. A fuel consumption deviation calculating means (for example, FI-ECU 30 in an embodiment described later) that calculates the deviation as a fuel consumption deviation, and the indicated vehicle speed calculating means is configured to minimize the fuel consumption deviation within the allowable range of the vehicle speed fluctuation. An instruction vehicle speed is calculated.
With this configuration, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's preference when performing the target fuel consumption travel control.

The invention according to claim 5 is the object detection means according to any one of claims 1 to 4, which is capable of detecting a distance and relative speed with a vehicle existing around the host vehicle (for example, The vehicle speed variation allowable range setting means includes a radar device 12) in an embodiment described later, and calculates the traveling speeds of a plurality of vehicles based on the output of the vehicle speed sensor and the output of the object detection means, respectively. The vehicle speed variation allowable range is set based on the maximum value or the minimum value of the traveling speed.
By comprising in this way, it can set to the optimal vehicle speed fluctuation | variation tolerance range according to the vehicle speed of the vehicle which exists around the own vehicle.

The invention according to claim 6 is the object detection means according to any one of claims 1 to 5, wherein the object detection means (for example, a distance and relative speed with respect to a vehicle existing around the host vehicle can be detected. A radar apparatus 12) according to an embodiment to be described later is provided, wherein the vehicle speed fluctuation allowable range setting means sets the vehicle speed fluctuation allowable range based on the number of vehicles detected by the object detection means.
By configuring in this way, it is possible to set an optimal vehicle speed fluctuation allowable range according to the degree of congestion of vehicles around the host vehicle.

The invention according to claim 7 is the invention according to any one of claims 1 to 3, wherein the object detecting means capable of detecting the distance and relative speed with respect to the object existing in the vehicle traveling direction, and the object A preceding vehicle determining means for determining a preceding vehicle based on an output of the detecting means; a target inter-vehicle distance setting means for setting a target inter-vehicle distance between the host vehicle and the preceding vehicle; and a preceding vehicle detected by the preceding vehicle determining means; An inter-vehicle distance deviation calculating means for calculating a deviation between the actual inter-vehicle distance and the target inter-vehicle distance set by the target inter-vehicle distance setting means as an inter-vehicle distance deviation, and the indicated vehicle speed calculating means includes the vehicle speed fluctuation allowable range. The command vehicle speed is calculated so that the inter-vehicle distance deviation is minimized.
With this configuration, when performing inter-vehicle control that maintains the inter-vehicle distance at the target inter-vehicle distance, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's preference.

The invention according to claim 8 is the invention according to any one of claims 1 to 7, wherein the vehicle speed fluctuation allowable range changing means changes an upper limit or a lower limit of the vehicle speed fluctuation allowable range by a switch operation of an occupant. It is characterized by doing.
With this configuration, the driver can easily and reliably perform an operation of changing the upper and lower limits of the vehicle speed fluctuation allowable range.

The invention according to claim 9 is the invention according to any one of claims 1 to 8, further comprising display means for displaying the vehicle speed fluctuation allowable range.
With this configuration, the occupant can easily check the currently set allowable range of vehicle speed fluctuation.

  According to the first aspect of the present invention, when the host vehicle is travel controlled within the vehicle speed fluctuation allowable range including the target vehicle speed, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's will. As a result, traveling control can be maintained without decelerating the vehicle speed that the driver does not like.

According to the second aspect of the invention, the upper limit of the vehicle speed fluctuation allowable range can be changed to a value larger than the target vehicle speed, so that the delay caused by the deceleration can be recovered.
Further, since the upper limit of the vehicle speed fluctuation allowable range is changed by adding the upper limit set value set by the operation of the occupant to the target vehicle speed, even if the driver frequently changes the target vehicle speed, There is no need to perform the complicated upper limit setting operation of the allowable range of fluctuations in vehicle speed.

According to the third aspect of the invention, the lower limit of the vehicle speed fluctuation allowable range can be changed to a value smaller than the target vehicle speed, so that the lower limit vehicle speed can be set to suit the driver's preference.
Further, since the lower limit of the vehicle speed fluctuation allowable range is changed by subtracting the lower limit set value set by the occupant's operation from the target vehicle speed, even if the driver frequently changes the target vehicle speed, There is no need to perform the complicated lower limit setting operation of the permissible vehicle speed fluctuation range.

According to the fourth aspect of the present invention, when the target fuel consumption travel control is performed, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's preference, so that the vehicle speed is decreased more than the driver's unfavorable vehicle speed. Therefore, the target fuel consumption travel control can be maintained.
In addition, when the upper limit of the vehicle speed fluctuation allowable range is changed to a value larger than the target vehicle speed, it is possible to recover the delay caused by the deceleration for reducing the fuel consumption in the target fuel consumption travel control.

  According to the invention according to claim 5, since it is possible to set the optimum vehicle speed fluctuation allowable range according to the vehicle speed of the vehicle existing around the host vehicle, the travel control according to the flow of the vehicle of the surrounding vehicle is performed. It can be carried out.

  According to the sixth aspect of the present invention, since it is possible to set an optimal vehicle speed fluctuation allowable range according to the degree of congestion of vehicles around the host vehicle, it is possible to perform travel control according to the degree of congestion.

According to the invention of claim 7, when performing inter-vehicle control that maintains the inter-vehicle distance at the target inter-vehicle distance, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's preference. The inter-vehicle distance control can be maintained within a range in which the vehicle speed is not decelerated from the vehicle speed.
In addition, when the upper limit of the vehicle speed fluctuation allowable range is changed to a value larger than the target vehicle speed, it becomes possible to recover the delay caused by the deceleration required during the inter-vehicle control.

  According to the invention which concerns on Claim 8, a driver | operator can perform the operation which changes the upper and lower limits of a vehicle speed fluctuation | variation allowable range simply and reliably.

  According to the ninth aspect of the present invention, the occupant can easily confirm the currently set allowable range of the vehicle speed.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a vehicle travel control device according to the present invention will be described below with reference to the drawings of FIGS.

  As shown in FIG. 1, the vehicle travel control device includes a vehicle speed sensor 11, a radar device (object detection means) 12, a return / acceleration switch 13, a set / deceleration switch 14, a release switch 15, and a target inter-vehicle distance. A distance selection switch 16, a target fuel consumption travel switch 17, a target fuel consumption switching switch (target fuel consumption setting means) 18, an upper limit vehicle speed change switch 19, a lower limit vehicle speed change switch 20, a throttle actuator 21, and multi-information 22 And an electronic control unit (FI-ECU) 30.

The vehicle speed sensor 11 detects the traveling speed of the host vehicle based on the number of rotations of the wheels.
The radar device 12 transmits an electromagnetic wave such as a laser beam or a millimeter wave toward the front in the traveling direction of the host vehicle, and when the transmitted electromagnetic wave is reflected by an object outside the host vehicle (for example, a preceding vehicle). The reflected wave is received, the transmitted electromagnetic wave and the received electromagnetic wave (reflected wave) are mixed to generate a beat signal, and the vehicle is detected based on the bead signal. Calculate distance and relative speed.

The return / acceleration switch 13, the set / deceleration switch 14, the release switch 15, and the target inter-vehicle distance selection switch 16 are switches that are operated mainly when performing control by ACC (hereinafter referred to as ACC control). . In the ACC control, when a preceding vehicle is detected, control is performed so as to follow the preceding vehicle while maintaining a predetermined inter-vehicle distance (hereinafter referred to as inter-vehicle control). When the preceding vehicle is not detected, the driver Control for running at a constant speed at the set vehicle speed (hereinafter referred to as constant speed running control) is performed.
When the set / deceleration switch 14 is turned ON during traveling, ACC control is started with the vehicle speed at that time as the set vehicle speed. The target inter-vehicle distance can be switched to, for example, three levels (small, medium, large) by operating the target inter-vehicle distance selection switch 16, and the inter-vehicle time is set by the target inter-vehicle distance selection switch 16, and the target inter-vehicle distance is A value calculated by multiplying the traveling speed of the vehicle is set as the target inter-vehicle distance.

When the return / acceleration switch 13 is turned on during the ACC control, the set vehicle speed increases in accordance with the number of operations and the time of operation. When the set / deceleration switch 14 is turned on during the ACC control, the number of operations and the time of operation are increased. Accordingly, the set vehicle speed decreases. If the brake pedal is depressed during the ACC control, the ACC control is temporarily released. If the return / acceleration switch 13 is turned on in this state, the ACC control is resumed. When the release switch 15 is turned on during ACC control, the ACC control is released.
In this embodiment, the return / acceleration switch 13 and the set / deceleration switch 14 constitute target vehicle speed setting means.

The target fuel consumption travel switch 17 is a switch for switching to target fuel consumption travel control that reduces the fuel consumption of the engine. The target fuel consumption travel control is a travel control capable of reducing fuel consumption while allowing an increase in the fluctuation range of the vehicle speed while ensuring the convenience of ACC. When the target fuel consumption travel switch 17 is turned on during the ACC control, the ACC control is switched to the target fuel consumption travel control. When the target fuel consumption travel switch 17 is turned off during the target fuel consumption travel control, the target fuel consumption travel control is switched to the ACC control. That is, ACC control and target fuel consumption travel control can be switched according to the driver's will.
The target fuel consumption can be switched to, for example, three levels (small, medium, large) by operating the target fuel consumption switch 18.

The upper limit vehicle speed change switch 19 and the lower limit vehicle speed change switch 20 are switches that are operated when changing the allowable range of the vehicle speed when executing the target fuel efficiency travel control, that is, the allowable range of the vehicle speed change according to the driver's preference. . The upper limit vehicle speed change switch 19 is turned on to change the upper limit of the vehicle speed fluctuation allowable range (vehicle speed fluctuation allowable range upper limit), the return / acceleration switch 13 is operated to increase, and the set / deceleration switch 14 is operated to decrease. Further, the lower limit vehicle speed change switch 20 is turned on to change the lower limit of the vehicle speed fluctuation allowable range (vehicle speed fluctuation allowable range lower limit), the return / acceleration switch 13 is operated to increase, and the set / deceleration switch 14 is operated to decrease. To do. The upper and lower limit change processing of the vehicle speed fluctuation allowable range will be described in detail later.
In this embodiment, the return / acceleration switch 13, the set / deceleration switch 14, the upper limit vehicle speed change switch 19 and the lower limit vehicle speed change switch 20 constitute vehicle speed variation allowable range changing means.

The outputs of the vehicle speed sensor 11, the radar device 12, and the switches 13 to 20 are input to the FI-ECU 30, and the FI-ECU 30 performs processing necessary for ACC control or target fuel consumption travel control, and the throttle actuator 21 and the multi-information 22. Output to.
The throttle actuator 21 controls the throttle opening of the engine, and the multi-information 22 displays on the predetermined display section the vehicle operating state and control state, and the upper and lower limits of the vehicle speed fluctuation allowable range set by the driver's operation. .

  The FI-ECU 30 is an electronic control device that controls the throttle opening of the engine of the host vehicle, and switches between an engine / mission control unit 32 including an actual fuel consumption calculation means 31, a target fuel consumption controller 33, and an ACC control unit 34. And a throttle opening degree control unit (running control means) 36, and the output of the throttle opening degree control unit 36 is output to the throttle actuator 21.

  The engine / mission control unit 32 outputs the actual fuel consumption calculated by the actual fuel consumption calculation means 31 to the target fuel consumption controller 33. The target fuel consumption controller 33 calculates the indicated vehicle speed so as to minimize the deviation between the actual fuel consumption input from the engine / mission control unit 32 and the target fuel consumption set by the target fuel consumption changeover switch 18, and outputs it to the switching unit 35. .

  On the other hand, the ACC control unit 34 includes preceding vehicle determination means (not shown) that determines whether an object existing ahead of the traveling direction of the host vehicle detected by the radar device 12 is a preceding vehicle, and is determined to be a preceding vehicle. If this is the case, the actual inter-vehicle distance from the preceding vehicle is detected, the indicated vehicle speed is calculated so that the deviation from the target inter-vehicle distance set by the target inter-vehicle distance selection switch 16 is minimized, and is output to the switching unit 35. . If the ACC control unit 34 determines that there is no preceding vehicle, the ACC control unit 34 calculates an instruction vehicle speed for performing constant speed running at the set vehicle speed set by the return / acceleration switch 13 or the set / deceleration switch 14. To the switching unit 35.

When the ACC control is selected according to the ON / OFF operation of the target fuel consumption travel switch 17, the switching unit 35 selects the instruction vehicle speed input from the ACC control unit 34 and the target fuel consumption travel control is selected. If so, the command vehicle speed input from the target fuel consumption controller 33 is output to the throttle opening control unit 36.
The throttle opening control unit 36 controls the throttle actuator 21 based on the indicated vehicle speed input from the switching unit 35, and controls the throttle opening of the engine.

  That is, when the target fuel efficiency travel switch 17 is OFF during ACC control, the command vehicle speed output by the ACC control unit 34 is selected by the switching unit 35, and the vehicle speed detected by the vehicle speed sensor 11 matches the set vehicle speed. Thus, the throttle actuator 21 is controlled based on the indicated vehicle speed.

  On the other hand, when the target fuel consumption travel switch 17 is turned on during the ACC control, the command vehicle speed output by the target fuel consumption controller 33 is selected by the switching unit 35 instead of the command vehicle speed output by the ACC control unit 34, and the command vehicle speed is set to this command vehicle speed. Based on this, the throttle actuator 21 is controlled. As a result, the target fuel consumption control is performed to reduce the fuel consumption rate of the engine while allowing the actual vehicle speed of the host vehicle to slightly vary with respect to the set vehicle speed of the ACC control.

Next, traveling control in this embodiment, particularly target fuel consumption traveling control, will be described with reference to the flowcharts of FIGS.
The flowchart shown in FIGS. 2 to 4 shows a target fuel consumption travel control routine. This target fuel consumption travel control routine is repeatedly executed by the FI-ECU 30 at regular intervals.

First, in step S101, the gradient of the road on which the host vehicle is traveling (road gradient) is calculated. The method for calculating the road gradient is arbitrary, but can be calculated from the relationship between the engine load and the vehicle body acceleration, for example.
Next, it progresses to step S102 and it is determined whether the target fuel consumption travel switch 17 is ON.
When the determination result in step S102 is “NO”, the process proceeds to step S103, where the command vehicle speed output from the ACC control unit 34 is input to the throttle opening control unit 36, and the set vehicle speed and the target set by the driver are set. In order to perform ACC control based on the inter-vehicle distance, the throttle opening control unit 36 controls the operation of the throttle actuator 21.

On the other hand, if the determination result in step S <b> 102 is “YES”, the process proceeds to step S <b> 104, and the target fuel consumption is set according to the value selected by the driver with the target fuel consumption switch 18.
In step S105, the set vehicle speed set by the driver in the ACC control is set as the target vehicle speed.
There is a trade-off relationship between the fuel consumption rate and the vehicle speed fluctuation in ACC control. When the target fuel consumption is “high”, the fuel consumption rate is allowed to be slightly increased to minimize the vehicle speed fluctuation in ACC control. When the fuel consumption is “medium”, the fuel consumption rate and the ACC control vehicle speed fluctuation are both set to an intermediate state, and when the target fuel consumption is “small”, the ACC control vehicle speed fluctuation is allowed to be slightly increased. It is set to minimize the consumption rate.

Next, the process proceeds to step S106, and the lower limit vehicle speed and the upper limit vehicle speed set by the driver are calculated based on the target vehicle speed set in step S105 and the lower limit set value and upper limit set value set by the driver by the switch operation. The “lower limit vehicle speed set by the driver” is calculated by subtracting the lower limit set value from the target vehicle speed, and the “upper limit vehicle speed set by the driver” is calculated by adding the upper limit set value to the target vehicle speed. By calculating in this way, the “lower limit vehicle speed set by the driver” can be set to a speed lower than the target vehicle speed, and the “upper limit vehicle speed set by the driver” can be set to a speed higher than the target vehicle speed. As a result, the vehicle speed fluctuation allowable range can be set to a range including the target vehicle speed.
The “lower limit vehicle speed set by the driver” may be set to 0 km / h.

  The “lower vehicle speed set by the driver” and “the upper vehicle speed set by the driver” are output to the multi-information 22 and displayed on the display unit. The driver can check the lower limit vehicle speed and the upper limit vehicle speed by looking at the display on the display unit. The display unit may be a meter of an instrument panel, may be shared with the display unit of the navigation device, or may be a dedicated display unit. Alternatively, instead of displaying on the display unit, a voice generation unit may notify the user by voice.

Here, the process of changing the upper and lower limit setting values will be described with reference to the flowchart of FIG.
First, in step S201, it is determined whether or not the upper limit vehicle speed change switch 19 is ON.
When the determination result in step S201 is “YES”, the process proceeds to step S202, and it is determined whether the return / acceleration switch 13 is turned on within a predetermined time after the upper limit vehicle speed change switch 19 is turned on.
When the determination result in step S202 is “YES”, the process proceeds to step S203, the upper limit set value is increased by a certain value, and the process proceeds to step S204.
If the determination result in step S202 is “NO”, the process proceeds to step S204 without executing the process in step S203.

In step S204, it is determined whether or not the set / deceleration switch 14 is turned on within a predetermined time after the upper limit vehicle speed change switch 19 is turned on.
When the determination result in step S204 is “YES”, the process proceeds to step S205, the upper limit set value is decreased by a certain value, and the process proceeds to step S206.
If the determination result in step S204 is “NO”, the process proceeds to step S206 without executing the process in step S205.
Furthermore, when the determination result in step S201 is “NO”, the process proceeds to step S206 without executing the processes in steps S202 to S205.

In step S206, it is determined whether or not the lower limit vehicle speed change switch 20 is ON.
If the determination result in step S206 is “YES”, the process proceeds to step S207, and it is determined whether the return / acceleration switch 13 is turned on within a predetermined time after the lower limit vehicle speed change switch 20 is turned on.
If the determination result in step S207 is “YES”, the process proceeds to step S208, the lower limit set value is decreased by a certain value, and the process proceeds to step S209.
If the determination result in step S207 is “NO”, the process proceeds to step S209 without executing the process in step S208.

In step S209, it is determined whether or not the set / deceleration switch 14 is turned on within a predetermined time after the lower limit vehicle speed change switch 20 is turned on.
When the determination result in step S209 is “YES”, the process proceeds to step S210, the lower limit set value is decreased by a certain value, and the execution of this routine is once ended.
If the determination result in step S209 is “NO”, the execution of this routine is temporarily terminated without executing the process of step S210.
If the determination result in step S206 is “NO”, the execution of this routine is temporarily terminated without executing the processes in steps S207 to S210.

That is, when the driver turns on the upper limit vehicle speed change switch 19 during the target fuel consumption travel control and turns on the return / acceleration switch in that state, the upper limit set value is increased according to the number of times the return / acceleration switch 13 is turned on. As a result, the upper limit vehicle speed can be set high, and when the set / deceleration switch 14 is turned ON, the upper limit set value can be decreased according to the number of ON / OFF operations of the set / deceleration switch 14, As a result, the upper limit vehicle speed can be set low.
Further, when the driver turns on the lower limit vehicle speed change switch 20 during the target fuel consumption travel control and the return / acceleration switch is turned on in this state, the lower limit set value is decreased according to the number of times the return / acceleration switch 13 is turned on. As a result, the lower limit vehicle speed can be set high, and when the set / deceleration switch 14 is turned on, the lower limit set value can be increased according to the number of times the set / deceleration switch 14 is turned on. The lower limit vehicle speed can be set low.

  Returning to FIG. 2, the process proceeds from step S106 to step S107, and based on the output of the radar device 12, a vehicle (hereinafter referred to as a surrounding vehicle) existing around the host vehicle (for example, a range of 100 m ahead of the host vehicle). Count the number.

Next, the process proceeds to step S108, and based on the output of the radar device 12, the relative speed between each of the surrounding vehicles and the host vehicle is detected.
Next, the process proceeds to step S109, and the vehicle speed of each of the surrounding vehicles is calculated by adding the relative speed of each vehicle detected in step S108 to the vehicle speed detected by the vehicle speed sensor 11 (another vehicle). Vehicle speed = own vehicle speed + relative speed).
Next, proceeding to step S110, the vehicle speed of the lowest vehicle speed among the surrounding vehicles is set as the vehicle speed fluctuation allowable range lower limit.
Next, proceeding to step S111, the vehicle speed of the highest vehicle speed among the surrounding vehicles is set as the vehicle speed fluctuation allowable range upper limit.
As a result, it is possible to set an optimal vehicle speed fluctuation allowable range according to the vehicle speed of the surrounding vehicle, and thus it is possible to perform economical traveling by reducing fuel consumption while following the vehicle flow of the surrounding vehicle.

  In this embodiment, the vehicle speed fluctuation allowable range setting means for setting the vehicle speed fluctuation allowable range based on the maximum value or the minimum value of the traveling speed of the surrounding vehicles by the FI-ECU 30 executing the processing of steps S108 to S111. Realized.

Next, it progresses to step S112 and it is determined whether the number of the surrounding vehicles detected in step S107 is more than the preset value (for example, 3 units) set beforehand.
If the determination result in step S112 is “YES” (more than the specified value), the process proceeds to step S113, the vehicle speed fluctuation allowable range lower limit is lowered by a predetermined value, and the process further proceeds to step S114, where the vehicle speed fluctuation allowable range upper limit is set. Is increased by a preset specified value, and the process proceeds to step S115. That is, when the number of surrounding vehicles is equal to or greater than a specified value, it is determined that the degree of congestion is large, and the vehicle speed fluctuation allowable range is widened. Thereby, the optimal vehicle speed fluctuation | variation tolerance range according to the congestion degree of the periphery of the own vehicle can be set. Note that the width of the vehicle speed fluctuation allowable range may be changed according to the number of surrounding vehicles.
If the determination result in step S112 is “NO” (smaller than the specified value), it is determined that the degree of congestion is small, and the process proceeds to step S115 without executing the processes in steps S113 and S114.

  In this embodiment, the FI-ECU 30 executes the processes of steps S112 to S114, thereby realizing a vehicle speed fluctuation allowable range setting means for setting a vehicle speed fluctuation allowable range based on the number of surrounding vehicles.

In step S115, based on the road gradient calculated in step S101, it is determined whether the road on which the host vehicle is traveling is an uphill.
If the determination result in step S115 is “YES”, the process proceeds to step S116, where the lower limit of the vehicle speed fluctuation allowable range is reduced according to the degree of the uphill, the target acceleration is reduced, or the acceleration is prohibited. The process proceeds to S119.

If the lower limit of the vehicle speed fluctuation allowable range is reduced when the road gradient is ascending in this way, the actual vehicle speed will decrease more than the target vehicle speed than when the lower limit of the vehicle speed fluctuation allowable range is not reduced. The increase in fuel consumption is suppressed and the increase in fuel consumption is prevented, so that the fuel consumption can be improved.
In addition, when the road gradient is uphill, if the target acceleration when the vehicle speed is matched with the target vehicle speed is reduced according to the road gradient, the throttle opening increases extremely compared to when accelerating on a flat road. Can be suppressed, and fuel consumption can be improved. If the upward gradient is large, acceleration is prohibited instead of decreasing the target acceleration.

If the determination result in step S115 is “NO”, the process proceeds to step S117 without executing the process of step S116, and the road on which the host vehicle is traveling is downhill based on the road gradient calculated in step S101. It is determined whether or not.
If the determination result in step S117 is “YES”, the process proceeds to step S118, the vehicle speed fluctuation allowable range upper limit is increased according to the degree of the downward gradient, the target acceleration is increased, or acceleration is permitted. The process proceeds to S119.

When the upper limit of the vehicle speed fluctuation allowable range is increased when the road gradient is downhill as described above, the increase in the actual vehicle speed with respect to the target vehicle speed is larger than when the upper limit of the vehicle speed fluctuation allowable range is not increased. Or even if it does not increase at all, the vehicle can be accelerated using gravity, so that the fuel consumption can be improved.
In addition, when the road gradient is downhill, even if the target acceleration when the vehicle speed is matched with the target vehicle speed is increased according to the road gradient, the vehicle is moved by gravity without increasing the throttle opening. Since the vehicle speed can be matched to the target vehicle speed by acceleration, fuel consumption can be improved.

If the determination result in step S117 is “NO”, the process proceeds to step S119 without executing the process in step S118.
In this embodiment, the FI-ECU 30 executes the processes of steps S115 to S118, thereby realizing a vehicle speed fluctuation allowable range setting means for setting the vehicle speed fluctuation allowable range based on the direction and magnitude of the road gradient.

In step S119, it is determined whether or not the vehicle speed fluctuation allowable range lower limit is smaller than the lower limit vehicle speed set in step S106 ("the lower limit vehicle speed set by the driver").
When the determination result in step S119 is “YES”, the process proceeds to step S120, “the lower limit vehicle speed set by the driver” is set as the lower limit of the vehicle speed fluctuation allowable range, and the process proceeds to step S121.
If the determination result in step S119 is “NO”, the process proceeds to step S121 without executing the process in step S120.
In step S121, it is determined whether or not the vehicle speed fluctuation allowable range upper limit is larger than the upper limit vehicle speed set in step S106 ("upper limit vehicle speed set by the driver").
If the determination result in step S121 is “YES”, the process proceeds to step S122, “the upper limit vehicle speed set by the driver” is set as the upper limit of the vehicle speed fluctuation allowable range, and the process proceeds to step S123.
If the determination result in step S121 is “NO”, the process proceeds to step S123 without executing the process in step S122.

  That is, when the “lower limit vehicle speed set by the driver” is larger than the lower limit of the allowable vehicle speed range calculated by executing the processing of steps S107 to S118, the lower limit of the allowable vehicle speed range is set to “the driver sets If the “upper limit vehicle speed set by the driver” is smaller than the upper limit of the vehicle speed fluctuation allowable range calculated by performing the processes of steps S107 to S118, the vehicle speed fluctuation allowable range upper limit is set to “driving”. Down to the maximum vehicle speed set by the operator. Thereby, it is possible to prevent the vehicle speed of the host vehicle from increasing or decreasing to a vehicle speed unexpected by the driver, and to prevent the driver from feeling uncomfortable.

In step S123, the fuel consumption deviation Q is calculated by subtracting the target fuel consumption set in step S104 from the actual fuel consumption calculated by the actual fuel consumption calculation means 31 of the engine / mission control unit 32. In this embodiment, the FI-ECU 30 executes the process of step S123, thereby realizing a fuel consumption deviation calculating means.
Next, the process proceeds to step S124, and as shown in the equations (1) and (2), the command vehicle speed Vs is calculated by the PID control calculation so that the fuel consumption deviation Q is minimized.
ΔVs = P · Q + D · dQ / dt + I∫Qdt (1)
Vs (t) = Vs (t−1) + ΔVs (2)

Next, the process proceeds to step S125, and a travel distance (actual travel distance) La in which the host vehicle actually travels from the start of fuel consumption travel control is calculated.
Next, the process proceeds to step S126, and the travel distance (virtual travel distance) Lb from the start of the fuel efficiency travel control when the host vehicle is assumed to have traveled at a constant speed at the target vehicle speed (that is, the set vehicle speed) from the start of the fuel efficiency travel control. The calculation is based on the actual travel time.
Next, the process proceeds to step S127, and it is determined whether or not the actual travel distance La is smaller than the virtual travel distance Lb.

If the determination result in step S127 is “NO” (La ≧ Lb), it is determined that there is no delay in the host vehicle, the process proceeds to step S128, and the indicated vehicle speed Vs (t) calculated in step S124 is determined. The final command vehicle speed Vs2 (t) is set, and the process proceeds to step S129.
On the other hand, if the determination result in step S127 is “YES” (La <Lb), it is determined that there is a delay in the host vehicle, the process proceeds to step S130, and the indicated vehicle speed Vs (t calculated in step S124 is determined. ) Is set as a final indicated vehicle speed Vs2 (t) (Vs2 (t) = Vs (t) + ΔVs2), and the process proceeds to step S129. The addition of the speed increase ΔVs2 is for making it possible to recover the delay, and is a measure for giving priority to recovery of the delay even if the fuel consumption is slightly sacrificed.

  In this embodiment, the FI-ECU 30 executes the processing of steps S125 to S127 to implement a delay determination unit, and the processing of step S130 implements a delay recovery unit.

In step S129, it is determined whether or not the final command vehicle speed Vs2 (t) is smaller than the vehicle speed fluctuation allowable range lower limit.
If the determination result in step S129 is “YES”, the process proceeds to step S131, a lower limit process for setting the vehicle speed fluctuation allowable range lower limit to the final indicated vehicle speed Vs2 (t) is executed, and the process proceeds to step S134.
If the determination result in step S129 is “NO”, the process proceeds to step S132 without executing the lower limit processing in step S131.

In step S132, it is determined whether or not the final command vehicle speed Vs2 (t) is larger than the vehicle speed fluctuation allowable range upper limit.
If the determination result in step S132 is “YES”, the process proceeds to step S133, an upper limit process for setting the vehicle speed fluctuation allowable range upper limit to the final command vehicle speed Vs2 (t) is executed, and the process proceeds to step S134.
If the determination result in step S132 is “NO”, the process proceeds to step S134 without executing the upper limit processing in step S133.
Then, in step S134, feedback control of the throttle opening of the engine is performed to control the throttle actuator 21 so that the vehicle speed detected by the vehicle speed sensor 11 matches the final command vehicle speed Vs2 (t).

In the travel control device configured as described above, the driver operates the upper limit vehicle speed change switch 19 or the lower limit vehicle speed change switch 20 at his / her own will, so that the vehicle speed variation allowable range is within the range including the target vehicle speed. It can be changed arbitrarily according to preference.
In addition, since the upper limit of the vehicle speed fluctuation allowable range is changed by adding the upper limit set value set by the occupant's operation to the target vehicle speed, even if the driver frequently changes the target vehicle speed, There is no need to perform a complicated upper limit setting operation of the permissible range of vehicle speed.
Further, since the lower limit of the vehicle speed fluctuation allowable range is changed by subtracting the lower limit set value set by the occupant's operation from the target vehicle speed, even if the driver frequently changes the target vehicle speed, There is no need to perform the complicated lower limit setting operation of the permissible vehicle speed fluctuation range.

  In particular, since the vehicle speed fluctuation allowable range upper limit can be changed to a vehicle speed higher than the set vehicle speed (target vehicle speed), the indicated vehicle speed can be set to a vehicle speed higher than the target vehicle speed as shown in FIG. Thus, for example, when there is a companion vehicle that accompanies the host vehicle, and the host vehicle and the accompanying vehicle are traveling at a vehicle speed close to the set vehicle speed in a situation where only the host vehicle is traveling under the target fuel consumption traveling control. In addition, even if the host vehicle decelerates to reduce fuel consumption, and the distance between the host vehicle and the accompanying vehicle temporarily increases, causing a delay in the host vehicle, the commanded speed of the host vehicle is thereafter set to be greater than the target vehicle speed. Since the speed can be set, the delay with respect to the accompanying vehicle can be recovered. In addition, since the instruction speed at that time does not exceed the “upper limit speed set by the driver”, the instruction speed is in a range that can be expected by the driver, and therefore, the driver does not feel uncomfortable.

  Moreover, since the vehicle speed fluctuation allowable range lower limit can be arbitrarily changed according to the driver's will, as shown in FIG. 7, it is possible to prevent the instruction vehicle speed from falling below the lower limit vehicle speed set by the driver, In addition, the vehicle speed of the host vehicle can be prevented from decreasing to a vehicle speed that does not follow the flow of surrounding vehicles.

[Other Examples]
The present invention is not limited to the embodiment described above.
For example, in the above-described embodiment, the radar device 12 (object detection means) that can detect an object that exists in front of the traveling direction of the host vehicle detects the surrounding vehicle that exists around the host vehicle, and the vehicle speed of the surrounding vehicle is detected. The upper and lower limits of the vehicle speed fluctuation allowable range are set based on the number of vehicles, but the object detection means is not limited to the radar device 12, but a rear radar capable of detecting an object existing behind the host vehicle, 360 degree radar capable of detecting an object existing around 360 degrees, a camera capable of photographing the front of the own vehicle in the traveling direction, a rear camera capable of photographing the rear of the own vehicle, and 360 degrees around the own vehicle can be photographed 360 degree cameras, and the upper and lower limits of the vehicle speed fluctuation allowable range can be set based on the data (vehicle speed and number) of surrounding vehicles detected in the detection direction of these object detection means. It is a function.
In the embodiment described above, the upper and lower limits of the vehicle speed fluctuation allowable range are changed by the occupant operating the switch, but the upper and lower limits of the vehicle speed fluctuation allowable range are changed by recognizing the voice generated by the occupant. Is also possible.

In the above-described embodiment, the present invention has been described in an aspect in which the present invention is applied to target fuel consumption traveling control. However, the present invention can also be applied to a vehicle traveling control apparatus configured as follows.
The vehicle travel control device includes a vehicle speed sensor that detects a vehicle speed, a target vehicle speed setting unit that sets a target vehicle speed, and a vehicle speed variation allowance that sets a vehicle speed variation allowable range that includes a target vehicle speed set by the target vehicle speed setting unit. Range setting means, instruction vehicle speed calculation means for calculating an instruction vehicle speed within the vehicle speed fluctuation allowable range, travel control means for performing vehicle travel control based on the instruction vehicle speed, and the vehicle speed fluctuation allowable range by an occupant's operation. Vehicle speed fluctuation allowable range changing means for changing, object detecting means capable of detecting a distance and relative speed between an object existing in the vehicle traveling direction, and preceding vehicle determining means for determining a preceding vehicle based on an output of the object detecting means A target inter-vehicle distance setting means for setting a target inter-vehicle distance between the host vehicle and the preceding vehicle, and an actual inter-vehicle distance between the preceding vehicle detected by the preceding vehicle determining means And an inter-vehicle distance deviation calculating unit that calculates a deviation from the target inter-vehicle distance set by the target inter-vehicle distance setting unit as an inter-vehicle distance deviation, and the indicated vehicle speed calculating unit includes the inter-vehicle distance within the vehicle speed variation allowable range. The command vehicle speed is calculated so that the distance deviation is minimized. This means that it can be applied to the ACC control in the embodiment described above.
In this way, when performing inter-vehicle control to keep the inter-vehicle distance at the target inter-vehicle distance, the vehicle speed fluctuation allowable range can be arbitrarily changed according to the driver's preference, so the vehicle is decelerated from the vehicle speed that the driver does not like The inter-vehicle distance control can be maintained within the range not to be caused.
In addition, when the upper limit of the vehicle speed fluctuation allowable range is changed to a value larger than the target vehicle speed, it becomes possible to recover the delay caused by the deceleration required during the inter-vehicle control.
Furthermore, the present invention is also applicable to CC control.

1 is a block diagram of a vehicle travel control device according to the present invention. FIG. It is a flowchart (the 1) which shows the target fuel consumption driving | running | working control of an Example. It is a flowchart (the 2) which shows the target fuel consumption driving control of an Example. It is a flowchart (the 3) which shows the target fuel consumption driving control of an Example. It is a flowchart which shows the upper / lower limit setting value change process of an Example. It is a time chart which shows a mode that the instruction | command vehicle speed in the target fuel consumption driving control of an Example converges to a set vehicle speed. It is a time chart which shows a mode that the command vehicle speed in the target fuel consumption driving control of an Example does not reduce from the vehicle speed which a driver | operator wants to make a minimum. It is a time chart which shows a mode that an instruction | command vehicle speed sticks to a set vehicle speed in a prior art. 6 is a time chart showing a state in which an instruction vehicle speed is reduced below a vehicle speed that the driver wants to set as a lower limit in the conventional technology.

Explanation of symbols

11 Vehicle speed sensor 12 Radar device (object detection means)
13 Return / Acceleration switch (target vehicle speed setting means, vehicle speed fluctuation allowable range changing means)
14 set / deceleration switch (target vehicle speed setting means, vehicle speed fluctuation allowable range changing means)
18 Target fuel consumption changeover switch (Target fuel consumption setting means)
19 Upper limit vehicle speed change switch (Vehicle speed fluctuation allowable range change means)
20 Lower limit vehicle speed change switch (Vehicle speed fluctuation allowable range change means)
30 FI-ECU (vehicle speed fluctuation allowable range setting means, instruction vehicle speed calculation means, fuel consumption deviation calculation means)
31 Actual fuel consumption calculation means 36 Throttle opening control section (travel control means)

Claims (9)

A vehicle speed sensor for detecting the vehicle speed;
Target vehicle speed setting means for setting the target vehicle speed;
Vehicle speed fluctuation allowable range setting means for setting a vehicle speed fluctuation allowable range including the target vehicle speed set by the target vehicle speed setting means;
Command vehicle speed calculation means for calculating command vehicle speed within the vehicle speed fluctuation allowable range;
Travel control means for performing travel control of the vehicle based on the indicated vehicle speed;
In a vehicular travel control device comprising:
A vehicle travel control apparatus comprising vehicle speed fluctuation allowable range changing means for changing the vehicle speed fluctuation allowable range by an operation of a passenger.   The vehicle speed variation allowable range changing means changes the upper limit of the vehicle speed variation allowable range by adding an upper limit set value set by an occupant's operation to the target vehicle speed. Travel control device.   The vehicle speed fluctuation allowable range changing means changes the lower limit of the vehicle speed fluctuation allowable range by subtracting a lower limit set value set by an occupant's operation from the target vehicle speed. The vehicle travel control device described. Actual fuel consumption calculating means for calculating actual fuel consumption;
Target fuel consumption setting means for setting the target fuel consumption;
A fuel consumption deviation calculating unit that calculates a deviation between the actual fuel consumption calculated by the actual fuel consumption calculating unit and the target fuel consumption set by the target fuel consumption setting unit as a fuel consumption deviation, and the indicated vehicle speed calculating unit includes the vehicle speed fluctuation The vehicle travel control apparatus according to any one of claims 1 to 3, wherein the command vehicle speed is calculated so that the fuel consumption deviation is minimized within an allowable range. An object detection means capable of detecting the distance and relative speed with a vehicle existing around the own vehicle;
The vehicle speed fluctuation allowable range setting means calculates the traveling speed of each of the plurality of vehicles based on the output of the vehicle speed sensor and the output of the object detection means, and the vehicle speed based on the calculated maximum value or minimum value of the traveling speed. The vehicle travel control apparatus according to any one of claims 1 to 4, wherein an allowable fluctuation range is set. An object detection means capable of detecting the distance and relative speed with a vehicle existing around the own vehicle;
6. The vehicle speed variation allowable range setting unit sets the vehicle speed variation allowable range based on the number of vehicles detected by the object detection unit. 6. Vehicle travel control device. An object detection means capable of detecting a distance and relative speed with an object existing in the vehicle traveling direction;
Preceding vehicle determination means for determining a preceding vehicle based on the output of the object detection means;
Target inter-vehicle distance setting means for setting the target inter-vehicle distance between the host vehicle and the preceding vehicle;
An inter-vehicle distance deviation calculating means for calculating a deviation between an actual inter-vehicle distance detected by the preceding vehicle determination means and an actual inter-vehicle distance and a target inter-vehicle distance set by the target inter-vehicle distance setting means;
The instruction vehicle speed calculating means calculates the instruction vehicle speed so that the inter-vehicle distance deviation is minimized within the vehicle speed fluctuation allowable range. Vehicle travel control device.   The vehicle travel control device according to any one of claims 1 to 7, wherein the vehicle speed fluctuation allowable range changing means changes an upper limit or a lower limit of the vehicle speed fluctuation allowable range by a switch operation of an occupant. .   The vehicle travel control apparatus according to any one of claims 1 to 8, further comprising display means for displaying the vehicle speed fluctuation allowable range.

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