JP2020196382A - Vehicular travel control device - Google Patents

Abstract

To provide a vehicular travel control device capable of realizing acceleration-deceleration suitable to driver's feeling regarding acceleration operation.SOLUTION: While an HEV_CU10 increments a first counter C1 for counting a number of deceleration request times, every range of a road grade S when detecting stepping-in operation to a brake pedal 16a within a first set time after starting deceleration control using a one-pedal-drive function, meanwhile, increments a second counter c2 for counting a number of acceleration request times, every range of the road grade S when detecting stepping-in operation to an acceleration pedal 15a within a second set time after starting deceleration control, and increases a corresponding learning value every time when the first counter C1 exceeds a first threshold value C1 th, meanwhile, decreases the corresponding learning value every time when the second counter C2 exceeds a second threshold value C2 th in the same range of the road grade S.SELECTED DRAWING: Figure 3

Description

The present invention relates to a vehicle traveling control device that automatically generates a braking force when an operation of the accelerator pedal to the fully closed side is detected.

Conventionally, in a driving control device for a vehicle such as an automobile, the driver operates the accelerator pedal to the fully closed (released) side as a function for accelerating or decelerating according to the driver's intention while reducing the driving burden on the driver. There is known a so-called one-pedal drive function that performs a predetermined deceleration control independent of the brake operation by the driver.

As a one-pedal drive function of this type, for example, in Patent Document 1, a target deceleration value is set by detecting a non-operating state of the accelerator pedal when the accelerator pedal return switch is turned on, and the target deceleration value is set. , A technique is disclosed in which correction is made based on at least one of a vehicle driving state and a road condition, and a braking addition mechanism is operated according to a target deceleration value to perform deceleration addition.

Japanese Unexamined Patent Publication No. 9-272419

However, for example, the timing of operating the accelerator pedal to the fully closed side with respect to the downward road surface gradient differs for each driver. Even on the same slope, the deceleration required thereafter differs depending on the timing at which the driver operates the accelerator pedal to the fully closed side. Therefore, as in the technique disclosed in Patent Document 1 described above, when the accelerator pedal is operated to the fully closed side, the control that simply sets the target deceleration value according to the road condition or the like is used. It may be difficult to achieve acceleration / deceleration that matches the driver's feeling.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle travel control device capable of realizing acceleration / deceleration that matches the feeling of a driver with respect to accelerator operation.

The vehicle travel control device according to one aspect of the present invention includes an accelerator operation detecting means for detecting a driver's operating state with respect to the accelerator pedal, a brake operation detecting means for detecting a driver's operating state with respect to the brake pedal, and a prior to the accelerator pedal. Target deceleration reference value using the deceleration control means that starts deceleration control of the own vehicle when the set operation to the fully closed side is detected, and the learning value set for each preset road gradient range. By correcting the above, the target deceleration calculation means for calculating the target deceleration for performing the deceleration control and the stepping operation on the brake pedal within the first set time after starting the deceleration control were detected. When, the deceleration request counting means that determines that the deceleration request has been made by the driver and counts the number of deceleration requests for each range of the road gradient, and the deceleration control is started within the second set time. When the stepping operation on the accelerator pedal is detected, it is determined that an acceleration request has been made by the driver, and the number of times of the acceleration request is counted for each range of the road slope. Every time the number of deceleration requests in the range exceeds the first set number of times, a correction is made to increase the learning value corresponding to the range of the road slope, and the number of times of the acceleration request in the same range of the road slope is the second. It is provided with a learning value correction means for making a correction for reducing the learning value corresponding to the range of the road slope every time the set number of times of 2 is exceeded.

According to the vehicle travel control device of the present invention, acceleration / deceleration that matches the driver's feeling can be realized for accelerator operation.

Schematic configuration diagram of the vehicle travel control device Flowchart showing deceleration control routine by one-pedal drive function Flowchart showing learning value calculation routine for setting target deceleration

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The vehicle 1 shown in FIG. 1 is, for example, a hybrid vehicle, and the vehicle 1 has an engine 2 and an electric motor (motor generator) 4 connected to the output shaft of the engine 2 with an automatic transmission 3 interposed therebetween. Have.

The vehicle 1 shown in the present embodiment is a four-wheel drive vehicle, and the output shafts of the automatic transmission 3 are connected to the left and right front wheels 5fl and 5fr and the left and right rear wheels 5rl and 5rr. Further, each wheel 5fl, 5fr, 5rl, 5rr (hereinafter, collectively referred to as "each wheel 5") has a hydraulic brake mechanism 8fl, 8fr, 8rr, 8rr (hereinafter, "each hydraulic brake mechanism 8"). (Collectively referred to as) is provided. In FIG. 1, reference numeral Dc is a center differential device, Df is a front differential device, and Dr is a rear differential device.

The control system for controlling the traveling of the vehicle 1 is mainly composed of a hybrid control unit (HEV_CU) 10 and a hydraulic control unit (HU_CU) 13. The HEV_ECU 10 and HU_CU 13 are composed of a well-known microcomputer including a CPU, a ROM, a RAM, and the like, and various programs, fixed data, and the like are stored in the ROM.

Further, on the input side of HEV_CU 10, an accelerator sensor 15 as an accelerator operation detection means for detecting the driver's operation state with respect to the accelerator pedal 15a, and a brake operation detection means for detecting the driver's brake operation state with respect to the brake pedal 16a. Various sensors such as the brake sensor 16 are connected to the HU_CU13, and the wheel speed sensors 17fl, 17fr, 17rl, 17rr (hereinafter, "each wheel speed sensor 17") for detecting the wheel speed of each wheel 5 are connected to the input side. Various sensors such as the front-rear acceleration sensor 18 are connected.

The accelerator sensor 15 can detect, for example, the operating speed of the accelerator pedal 15a and the fully open or fully closed state of the accelerator pedal 15a. Further, the brake sensor 16 can detect, for example, the operating speed of the brake pedal 16a, the fully open or fully closed state of the brake pedal 16a, and the like.

Further, a driver monitoring system 19 is connected to the input side of HEV_CU 10. Here, the driver monitoring system 19 has, for example, a camera arranged so as to face the driver's seat, and performs face recognition of the driver or the like based on an image captured by the camera. This makes it possible for the driver monitoring system 19 to identify the driver in operation.

The HEV_CU 10 calculates the required torque and the like for the engine 2 and the electric motor 4 based on signals from various sensors by executing a program or the like read from the ROM in the CPU, for example, and these the engine 2 and the electric motor 4 Comprehensive drive control of.

Further, the HEV_CU 10 controls the switching of the traveling mode through the control of various clutches and the like (not shown) provided in the automatic transmission 3. In the present embodiment, the HEV_CU 10 is set to the EG mode in which the engine 2 is used alone, the HEV mode in which the engine 2 and the electric motor 4 are used in combination, or the EV mode in which the electric motor 4 is used alone. It is possible to switch to either.

Further, the HEV_CU 10 can perform braking control and the like by engine braking using the engine 2, regeneration by the electric motor 4, operation of each hydraulic braking mechanism 8 through the HU_CU 13, or a predetermined combination thereof. ing.

Therefore, in the HEV_CU 10, in addition to the above-mentioned HU_CU 13, for example, various control units such as an engine control unit (ECU) 11 and a power control unit (PCU) 12 having an inverter 12a built-in are included in the CAN (Control Area Network) and the like. It is connected via.

In the ECU 11, control information such as required torque is input from HEV_CU 10, and detection information is input from various sensors (not shown) such as a crank angle sensor provided in the engine 2. Then, the ECU 11 drives the engine 2 by controlling various devices such as a fuel injection amount, an ignition timing, and an electronically controlled throttle valve based on these input information.

The PCU 12 receives control information such as required torque from HEV_CU 10 and acquires current values, voltage values, various sensor signals, and the like flowing through the electric motor 4 from the inverter 12a. Then, the PCU 12 drives the electric motor 4 by converting the DC power from the battery 7 into AC power through the control of the inverter 12a.

Further, during deceleration traveling, the PCU 12 causes the electric motor 4 to function as a generator through control of the inverter 12a, converts the AC power regenerated by the electric motor 4 into DC power, and charges the battery 7. When the electric motor 4 functions as a generator, regenerative braking force by the regenerative brake is applied to each wheel 5. Although this regenerative braking force is applied to the drive wheels, since the vehicle 1 of the present embodiment is a four-wheel drive vehicle, the regenerative braking force is applied to all the wheels 5.

The HU_CU 13 is a hydraulic pressure generator composed of a booster pump, an accumulator, etc., a pressure adjustment control valve that adjusts the hydraulic pressure at the time of brake operation and supplies it to the wheel cylinder of each hydraulic pressure brake mechanism 8, and brakes each hydraulic brake mechanism 8. It is equipped with an on-off control valve that opens and closes the hydraulic circuit that supplies the hydraulic pressure. The HU_CU 13 appropriately supplies the brake fluid pressure to each hydraulic brake mechanism 8 based on the control signal from the HEV_CU 10 (the hydraulic pressure may be supplied by an electronically controlled booster).

In the vehicle 1 having such a configuration, the HEV_CU 10 has a so-called one-pedal drive function that performs acceleration / deceleration control only by operating the accelerator pedal 15a, and performs a preset operation to the fully closed side of the accelerator pedal 15a. When it is detected, deceleration control independent of the operation on the brake pedal is started.

That is, when the HEV_CU 10 detects, for example, that the accelerator pedal 15a is operated to the fully closed side at an operating speed equal to or higher than the set operating speed and the accelerator pedal 15a is fully closed, the driver has an intention to decelerate. Judging that, the deceleration control is started without waiting for the stepping operation on the brake pedal 16a.

Here, HEV_CU10 calculates the target deceleration used for deceleration control by correcting the preset reference value of the target deceleration (target deceleration reference value) with the learning value.

At that time, HEV_CU10 variably sets the learning value for each preset range of the road gradient S. That is, HEV_CU10 calculates the road gradient S of the road on which the vehicle 1 is traveling based on, for example, the signal from the front-rear acceleration sensor 18, and the calculated road gradient S is -5% <S, -5% ≦. It is determined whether the product belongs to the range of S <-2%, -2% ≤ S ≤ 2%, 2% <S ≤ 5%, 5% <S. Then, HEV_CU10 appropriately corrects the learning value corresponding to the range of the current road gradient S.

Specifically, HEV_CU10 determines that the driver has requested deceleration when the stepping operation on the brake pedal 16a is detected within the first set time after starting the deceleration control by the one-pedal drive function (). That is, it is determined that the deceleration is insufficient), and the number of deceleration requests is counted for each range of the road gradient. On the other hand, when HEV_CU10 detects a depression operation on the accelerator pedal 15a within a second set time (for example, second set time> first set time) after starting deceleration control by the one-pedal drive function, It is determined that the driver has requested acceleration (that is, it is determined that the deceleration is too strong), and the number of acceleration requests is counted for each range of the road gradient. Since it is assumed that the acceleration request is made after the deceleration by the one-pedal drive function has progressed to some extent, the second set time is set longer than the first set time in the present embodiment. However, for example, it is possible to set the second set time to the same length as the first set time.

Then, the HEV_CU10 obtains a predetermined amount of learning value corresponding to the range of the road gradient every time the number of deceleration requests in the same road gradient range exceeds the first set number of times through each deceleration control by the one-pedal drive function. Make corrections to increase. On the other hand, every time the number of acceleration requests in the same road slope range exceeds the second set number of times, a correction is performed to reduce the learning value corresponding to the road slope range by a predetermined amount.

Here, as the learning value calculated for each range of the road gradient, the gain multiplied by the target deceleration reference value or the addition to the target deceleration reference value (subtract if negative). It is possible to preferably adopt the added value to be added. It is desirable that this learning value is further calculated for each driver recognized by the driver monitoring system 19.

As the target deceleration reference value, for example, a preset fixed value or a variable value that increases as the vehicle speed of the vehicle 1 increases can be adopted.

As described above, in the present embodiment, the HEV_CU 10 realizes each function as a deceleration control means, a target deceleration calculation means, an acceleration request counting means, a deceleration request counting means, and a learning value correction means.

Next, the deceleration control by the one-pedal drive function executed in the above-mentioned HEV_CU10 will be described according to the flowchart of the deceleration control routine shown in FIG.

This routine is repeatedly executed in HEV_CU 10 at set time intervals, and when the routine starts, HEV_CU 10 first reads recognition information about the driver from the driver monitoring system 19 in step S101.

Subsequently, in step S102, HEV_CU 10 detects the road gradient S of the road on which the vehicle 1 is currently traveling, based on, for example, a signal from the front-rear acceleration sensor 18.

Then, when the HEV_CU 10 proceeds to step S103, the learning value corresponding to the current road gradient S and the driver is read out, and in the subsequent step S104, the target deceleration reference value is corrected by the learning value, and then the process proceeds to step S105.

In step S105, HEV_CU 10 checks whether or not the current accelerator pedal 15a is in the fully closed state based on the signal from the accelerator opening sensor 15.

Then, HEV_CU 10 exits the routine as it is when it is determined that the accelerator pedal 15a has a predetermined opening degree, and proceeds to step S106 when it is determined that the accelerator pedal 15a is in the fully closed state.

Proceeding from step S105 to step S106, the HEV_CU 10 is based on the signal from the accelerator opening sensor 15, and the accelerator pedal 15a is fully operated at a speed equal to or higher than the set speed until the accelerator pedal 15a is fully closed. Check if it was operated on the closed side.

Then, when it is determined that the accelerator pedal 15a is operated to the fully closed side at an operation speed lower than the set speed, the HEV_CU 10 exits the routine as it is, and the accelerator pedal 15a is operated to the fully closed side at an operation speed equal to or higher than the set speed. If it is determined, the process proceeds to step S107.

Proceeding from step S106 to step S107, HEV_CU10 starts deceleration control by the one-pedal drive function using the target deceleration calculated in step S104 described above.

In the following step S108, the HEV_CU 10 checks whether or not the driver has stepped on the brake pedal 16a during the deceleration control based on the signal from the brake pedal sensor 16.

Then, when it is determined that the stepping operation on the brake pedal 16a is performed (that is, the brake is turned on), the HEV_CU10 proceeds to step S110, and when it is determined that the stepping operation on the brake pedal 16a is not performed. To step S109.

Proceeding from step S108 to step S109, HEV_CU 10 checks whether or not the driver has stepped on the accelerator pedal 15a during deceleration control based on the signal from the accelerator pedal sensor 15.

Then, when HEV_CU10 determines that the accelerator pedal 15a has been depressed (that is, the accelerator is turned on), the process proceeds to step S110, and when it is determined that the accelerator pedal 15a has not been depressed. Return to step S108 while maintaining the deceleration control.

When the process proceeds from step S108 or step S109 to step S110, HEV_CU10 exits the routine after finishing the deceleration control by the target deceleration.

Next, the learning control for setting the target deceleration used for the deceleration control described above will be described according to the flowchart of the learning value calculation routine shown in FIG.

This routine is repeatedly executed in HEV_CU10 at set time intervals, and when the routine starts, HEV_CU10 first checks in step S201 whether or not deceleration control by the one-pedal drive function is currently in progress.

Then, HEV_CU 10 exits the routine as it is when it is determined that the deceleration control by the one-pedal drive function is not in progress, and proceeds to step S202 when it is determined that the deceleration control by the one-pedal drive function is in progress.

From step S201 to step S202, HEV_CU10 reads the road gradient S of the road on which the vehicle 1 is currently traveling.

In the following step S203, HEV_CU10 reads the counter C1 and the counter C2 corresponding to the range of the road slope to which the road slope S read in the step S202 belongs. Here, the counter C1 is a counter for counting the number of times a deceleration request is made through the stepping operation of the brake pedal 16a by the driver during the deceleration control by the one-pedal drive function. Further, the counter C2 is a counter for counting the number of times that the driver has requested acceleration through the depression operation of the accelerator pedal 15a during the deceleration control by the one-pedal drive function.

Proceeding from step S203 to step S204, HEV_CU10 checks whether or not the driver has stepped on the brake pedal 16a (that is, whether or not the brake has been turned on).

Then, HEV_CU10 proceeds to step S210 when it is determined that the brake is not turned on, and proceeds to step S205 when it is determined that the brake is turned on.

Proceeding from step S204 to step S205, HEV_CU10 determines whether or not the stepping operation on the brake pedal 16a described above is performed within the first set time after starting the deceleration control by the one-pedal drive function. To find out.

Then, when it is determined that the stepping operation is performed after the lapse of the first set time, HEV_CU10 directly exits the routine and determines that the stepping operation is performed within the first set time. If so, the process proceeds to step S206.

Proceeding from step S205 to step S206, HEV_CU10 increments counter C1 and, in subsequent step S207, checks whether or not the value of counter C1 is equal to or higher than the preset threshold value C1th.

Then, HEV_CU10 exits the routine as it is when it is determined that the counter C1 is less than the threshold value C1th, and proceeds to step S208 when it is determined that the counter C1 is equal to or more than the threshold value C1th.

Proceeding from step S207 to step S208, HEV_CU10 corrects the learning value corresponding to the range of the current road gradient S to the increasing side by a preset correction amount, and after clearing the counter C1 in the following step S209. , Exit the routine.

Further, when proceeding from step S204 to step S210, HEV_CU10 checks whether or not the driver has depressed the accelerator pedal 15a (that is, whether or not the accelerator has been turned on).

Then, HEV_CU10 exits the routine as it is when it is determined that the accelerator is not turned on, and proceeds to step S211 when it is determined that the accelerator is turned on.

Proceeding from step S210 to step S211, HEV_CU10 determines whether or not the stepping operation on the accelerator pedal 15a described above is performed within the second set time after starting the deceleration control by the one-pedal drive function. To find out.

Then, when it is determined that the stepping operation is performed after the lapse of the second set time, HEV_CU10 directly exits the routine and determines that the stepping operation is performed within the second set time. If so, the process proceeds to step S212.

Proceeding from step S211 to step S212, HEV_CU10 increments the counter C2, and in the subsequent step S213, checks whether or not the value of the counter C2 is equal to or higher than the preset threshold value C2th.

Then, HEV_CU10 exits the routine as it is when it is determined that the counter C2 is less than the threshold value C2th, and proceeds to step S214 when it is determined that the counter C2 is equal to or more than the threshold value C2th.

Proceeding from step S213 to step S214, HEV_CU10 corrects the learning value corresponding to the current range of the road gradient S to the decreasing side by a preset correction amount, and after clearing the counter C2 in the following step S215. , Exit the routine.

According to such an embodiment, the target deceleration is calculated by correcting the target deceleration reference value using the learning value set for each range of the road gradient S set in advance, and the calculated target deceleration is calculated. When the deceleration control is performed by the one-pedal drive function based on the above, when the stepping operation on the brake pedal 16a is detected within the first set time after the deceleration control is started, it is determined that the driver has requested the deceleration. When the first counter C1 that counts the number of deceleration requests for each range of the road gradient S is incremented, while the depression operation on the accelerator pedal 15a is detected within the second set time after the deceleration control is started. It is determined that there is an acceleration request by the driver, the second counter C2 that counts the number of acceleration requests for each range of the road gradient S is incremented, and the number of deceleration requests in the same range of the road gradient S ( Every time the first counter C1) exceeds the first set number of times (first threshold value C1th), a correction is made to increase the learning value corresponding to the range of the road gradient S, and acceleration in the same range of the road gradient S is performed. For accelerator operation, correction is performed to reduce the learning value corresponding to the range of the road gradient S every time the number of requests (second counter C2) exceeds the second set number of times (second threshold C2th). It is possible to realize acceleration / deceleration that matches the feeling of the driver.

In this case, if the learning value is further different for each driver, acceleration / deceleration that more closely matches the driver's feeling can be realized.

The present invention is not limited to the embodiments described above, and various modifications and modifications can be made, and these are also within the technical scope of the present invention. For example, in the above-described embodiment, an example in which the present invention is applied to a hybrid vehicle has been described, but the present invention is not limited to this, and for example, only an engine or only an electric motor is used as a power source. Of course, it can also be applied to various vehicles.

Further, the range of the road slope is not limited to the above-mentioned range, and for example, it is possible to set the range of the road slope in more detail.

1 ... Vehicle 2 ... Engine 3 ... Automatic transmission 4 ... Electric motor 5 ... Wheels 7 ... Battery 8 ... Hydraulic brake mechanism 10 ... Hybrid control unit (deceleration control means, target deceleration calculation means, acceleration request counting means, deceleration request Counting means, learning value correction means)
11… Engine control unit 12… Power control unit 12a… Inverter 13… Hydraulic control unit 15… Accelerator sensor 15a… Accelerator pedal 16… Brake sensor 16a… Brake pedal 17… Wheel speed sensor 18… Front-rear acceleration sensor 19… Driver monitoring system

Claims (4)

Accelerator operation detection means for detecting the driver's operation status with respect to the accelerator pedal, and
Brake operation detection means for detecting the driver's operation status with respect to the brake pedal,
A deceleration control means that starts deceleration control of the own vehicle when a preset operation to the fully closed side of the accelerator pedal is detected.
A target deceleration calculation means for calculating the target deceleration for performing the deceleration control by correcting the target deceleration reference value using the learning value set for each preset road gradient range.
When the stepping operation on the brake pedal is detected within the first set time after the deceleration control is started, it is determined that the driver has requested deceleration, and the number of deceleration requests is set for each range of the road gradient. Deceleration request counting means to count to
When the depression operation on the accelerator pedal is detected within the second set time after the deceleration control is started, it is determined that the driver has requested acceleration, and the number of acceleration requests is set for each range of the road gradient. Acceleration request counting means to count to
Every time the number of deceleration requests in the same road slope range exceeds the first set number of times, a correction is made to increase the learning value corresponding to the road slope range, and the said in the same road slope range. A learning value correction means that performs a correction that reduces the learning value corresponding to the range of the road slope each time the number of acceleration requests exceeds the second set number of times.
A vehicle travel control device characterized by being equipped with. The deceleration control means is characterized in that the deceleration control is started when it is detected that the accelerator pedal is operated to the fully closed side at an operation speed equal to or higher than the set operation speed and the accelerator pedal is in the fully closed state. The vehicle travel control device according to claim 1. Equipped with a driver monitoring system that can recognize the driver
The learning value correction means corrects the learning value for each recognized driver.
The vehicle use according to claim 1 or 2, wherein the target deceleration calculation means calculates the target deceleration for each driver by using the learning value corrected for each driver. Travel control device. The vehicle travel control device according to any one of claims 1 to 3, wherein the second set time is longer than the first set time.

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