Vehicle control devices

Abstract

The present invention provides a vehicle control device that can reduce the burden on the driver when operating the accelerator without reducing the vehicle's drivability. The vehicle control device estimates the driver's ankle load when operating the accelerator, sets a standard first driving force characteristic when the ankle load is small, and sets a second driving force characteristic when the ankle load is large, with a target driving force that is smaller than the first driving force characteristic and can reduce the ankle load. The vehicle's driving force is controlled based on the target driving force. In the control device, the target driving force when the second driving force characteristic is set is reduced compared to the target driving force when the first driving force characteristic is set, thereby reducing the difference between the ratio of the vehicle acceleration generated in response to the pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration generated in response to the pedaling force when the second driving force characteristic is set.

Description

Technical Field

[0001] The present invention relates to a vehicle control device that sets a target driving force corresponding to a driver's depression operation of an accelerator pedal and controls the vehicle's driving force based on the set target driving force. Background Art

[0002] Patent Document 1 describes a vehicle powertrain control device, the purpose of which is to reduce the driver's burden when operating the accelerator pedal without complicating the vehicle structure. The vehicle powertrain control device described in Patent Document 1 controls the driving force during driving based on a driving force characteristic, which represents a target driving force corresponding to the accelerator opening (the amount of accelerator pedal operation). Furthermore, the vehicle powertrain control device described in Patent Document 1 includes a sensor that detects the driver's driving posture. Based on the detection results of this sensor, the magnitude of the driver's ankle burden when operating the accelerator pedal is estimated. If the driver's ankle burden is estimated to be relatively small, the driving force characteristic is set to a "standard characteristic." If the driver's ankle burden is estimated to be relatively large, the driving force characteristic is changed to a "corrected characteristic," in which the target driving force is smaller than the target driving force under the "standard characteristic."

[0003] Furthermore, Patent Document 2 describes a vehicle pedal device designed to easily adjust the initial angle and play angle of the accelerator pedal. The vehicle pedal device described in Patent Document 2 includes an electric actuator that adjusts the initial angle of the accelerator pedal relative to the floor when the accelerator pedal is in its initial position. By adjusting the initial angle and play angle of the accelerator pedal using the electric actuator, the relationship between the accelerator pedal's depression angle and the reaction force can be arbitrarily set according to the driver's preference.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-209791

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 2005-301441 Summary of the Invention

[0008] Technical problem to be solved by the invention

[0009] As described above, the vehicle powertrain control device described in Patent Document 1 estimates the magnitude of the ankle burden on the driver when operating the accelerator pedal. Generally speaking, when the driver places their heel on the floor to operate the accelerator pedal, the angle formed by the driver's sole and shin (ankle angle) is small in the area of low accelerator opening (small amount of accelerator pedal depression). When the ankle angle is small, the load on the ankle and leg muscles is greater than when the ankle angle is large. In other words, the ankle burden is large. In response to this, in the vehicle powertrain control device described in Patent Document 1, when it is estimated that the driver's ankle burden is relatively large, the vehicle's driving force characteristics that define the target driving force corresponding to the accelerator opening are changed from "standard characteristics" to "corrected characteristics." Under the "corrected characteristics," the target driving force corresponding to the accelerator opening area becomes smaller than the target driving force under the "standard characteristics." When the target driving force is reduced under the "modified characteristics," the driver's accelerator pedal pressure to obtain driving force increases compared to the "standard characteristics." As a result, the driver's accelerator pedal pressure decreases in the low accelerator opening range, where ankle stress is high. Therefore, by changing the driving force characteristics from the "standard characteristics" to the "modified characteristics," the driver's accelerator pedal pressure is reduced.

[0010] In addition, in the vehicle powertrain control device described in Patent Document 1, as Figure 1 As shown, the characteristic change rate (slope B of the driving force characteristic diagram) of the "corrected characteristic" in the normal accelerator opening range, where the accelerator opening is set between the first opening threshold (APO01) and the second opening threshold (APO02), is equal to the characteristic change rate (slope A of the driving force characteristic diagram) of the "standard characteristic." This minimizes the difference between the "standard characteristic" and the "corrected characteristic." Furthermore, it is believed that even when setting the target driving force based on the "corrected characteristic," the accelerator pedal stroke usable in the normal accelerator opening range can be maximized.

[0011] However, in the powertrain control device for a vehicle described in Patent Document 1, when the driving force characteristics of the vehicle are changed from "standard characteristics" to "corrected characteristics", the driver will feel a sense of insufficient driving force, and as a result, the drivability of the vehicle may be reduced. As described above, the powertrain control device for a vehicle described in Patent Document 1 changes the driving force characteristics from "standard characteristics" to "corrected characteristics" without changing the characteristic change speed to "corrected characteristics" in which the target driving force is reduced. As a result, the commonly used accelerator opening area such as Figure 2 As shown by the rightward arrow in the direction of increasing the accelerator opening ( Figure 2 Therefore, compared to the "standard characteristics", the driver will Figure 2 As indicated by the upward arrow in the figure, the accelerator pedal is operated in a region where the pedal load (pedal force) is greater. Specifically, when the driving force characteristics change from the "standard characteristics" to the "modified characteristics," the driver operates the accelerator pedal with a larger accelerator opening and greater pedal force to achieve the desired driving force. As a result, the characteristic change rate relative to the accelerator opening remains constant, while the required accelerator pedal operation and pedal force increase. This causes the driver to feel as if the vehicle's driving force is insufficient.

[0012] The present invention has been conceived in view of the above-mentioned technical problems, and an object of the present invention is to provide a vehicle control device that can reduce the burden on the driver when operating the accelerator pedal without degrading the drivability of the vehicle.

[0013] Technical solutions to solve problems

[0014] In order to achieve the above-mentioned object, the present invention is a control device for a vehicle, wherein the vehicle has an accelerator pedal in which the reaction force (pedal load) against the pedaling force during the pedaling operation increases as the accelerator opening corresponding to the operation amount of the vehicle driver's pedaling operation increases, and the control device sets a driving force characteristic that specifies a target driving force corresponding to the accelerator opening, and estimates the reaction force acting on the driver during the pedaling operation based on the body shape (Japanese: body posture) of the driver sitting in the driver's seat (for example, driving posture, physique, sitting position, seat position, foot size, etc.). The driver's ankle and leg ankle loads are determined, and when the estimated ankle load is smaller than a predetermined correction determination threshold value (in the case of a standard ankle load), a first driving force characteristic is set as the standard (becoming a benchmark) driving force characteristic; when the estimated ankle load is greater than or equal to the correction determination threshold value, a second driving force characteristic is set as the driving force characteristic capable of reducing the ankle load; the target driving force is calculated based on the set first driving force characteristic or the second driving force characteristic and the accelerator opening; and the calculated target driving force is calculated based on the calculated The target driving force of the vehicle is controlled by the target driving force of the second driving force characteristic, wherein at least in a frequently used accelerator opening range, the target driving force of the second driving force characteristic is smaller than the target driving force of the first driving force characteristic, and the frequently used accelerator opening range is defined as a portion of the accelerator opening range that is frequently used in the entire opening range from fully closed to fully open. The control device is characterized in that it includes a controller that estimates the ankle load, sets the first driving force characteristic or the second driving force characteristic, and calculates the target driving force to control the driving force of the vehicle. Control is performed, and the controller has an acceleration feeling maintaining unit, which reduces the target driving force calculated based on the accelerator opening when the second driving force characteristic is set, compared with the target driving force calculated based on the accelerator opening when the first driving force characteristic is set, and reduces the difference in the ratio of the acceleration of the vehicle (front and rear acceleration) generated corresponding to the pedaling force to the pedaling force in the following two situations, namely, the situation where the first driving force characteristic is set and the situation where the second driving force characteristic is set.

[0015] In addition, the acceleration feeling maintaining unit in the present invention can also be constructed as follows: by making the ratio of the increase in the target driving force under the second driving force characteristic to the increase in the accelerator opening in the normal accelerator opening area greater than the ratio of the increase in the target driving force under the first driving force characteristic to the increase in the accelerator opening (the slope on the accelerator opening-target driving force curve graph) to reduce the difference.

[0016] Furthermore, the acceleration feeling maintaining means in the present invention may be configured to set a ratio of an increase in the target driving force to an increase in the accelerator opening under the second driving force characteristics based on the estimated magnitude of the ankle load.

[0017] Furthermore, the vehicle in the present invention may include a reaction force actuator capable of changing and controlling the reaction force of the accelerator pedal, and the acceleration feel maintaining unit may be configured to reduce the reaction force by controlling the reaction force actuator, thereby reducing the difference.

[0018] Furthermore, the acceleration feel maintaining means in the present invention may be configured to set an amount of reduction of the reaction force by the reaction force actuator based on the estimated magnitude of the ankle load.

[0019] Effects of the Invention

[0020] In the vehicle control device of the present invention, to reduce the burden on the driver when operating the accelerator pedal, particularly to reduce the load on the driver's ankles and leg muscles, the driver's ankle load when operating the accelerator pedal is estimated, and the vehicle's driving force characteristics are set based on the magnitude of the estimated ankle load. If the magnitude of the estimated ankle load is a standard ankle load smaller than a correction determination threshold, a first driving force characteristic is set that specifies a standard target driving force. If the magnitude of the estimated ankle load exceeds the correction determination threshold, a second driving force characteristic is set that specifies a target driving force smaller than the first driving force characteristic. In other words, if a large ankle load exceeding the correction determination threshold is estimated to be acting, the driving force characteristics are corrected to reduce the specified target driving force. By setting the second driving force characteristic with a smaller target driving force, the driver, when operating the accelerator pedal to obtain driving force, will depress the accelerator pedal more than when operating under the first driving force characteristic. As a result, the chances and frequency of operating the accelerator pedal in the low accelerator opening range (small accelerator pedal depression amount) where the ankle load increases due to a small ankle angle decreases, thereby reducing the burden on the driver when operating the accelerator pedal.

[0021] As described above, by setting the second driving force characteristic when it is estimated that the driver's ankle load is large, the target driving force is reduced compared to normal, thereby reducing the driver's ankle load. However, if only the target driving force is reduced under the second driving force characteristic, the driver may feel a sense of insufficient driving force or a sense of discomfort with the acceleration, which may reduce the drivability of the vehicle. Therefore, in the vehicle control device of the present invention, when the second driving force characteristic is set, that is, when the driving force characteristic is modified to reduce the specified target driving force, the difference between the ratio of the vehicle acceleration (specifically, the front-to-back acceleration) generated in response to the driver's accelerator pedal operation under the first driving force characteristic to the pedaling force and the ratio of the vehicle acceleration (specifically, the front-to-back acceleration) generated in response to the driver's accelerator pedal operation under the second driving force characteristic to the pedaling force is reduced. In other words, the ratio of the vehicle acceleration to the pedaling force, as described above, is controlled so that it does not differ significantly when the first driving force characteristic is set and when the second driving force characteristic is set. For example, by making the ratio of the increase in target driving force to the increase in accelerator pedal position under the second driving force characteristic greater than the ratio of the increase in target driving force to the increase in accelerator pedal position under the first driving force characteristic (specifically, the slope on a graph of accelerator pedal position - target driving force), the aforementioned difference can be reduced. Alternatively, by providing a reaction force actuator and controlling the reaction force actuator to reduce the reaction force to the driver's pedaling force, the aforementioned difference can be reduced. As a result, when the second driving force characteristic is set to reduce the load on the driver's ankle, while the target driving force is reduced compared to normal, the ratio of the vehicle driving force (or acceleration) generated in response to the driver's pedaling force is increased compared to a case where the control implemented by the vehicle control device of the present invention is not applied. In other words, the difference between the ratio of the vehicle acceleration to the driver's pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration to the driver's pedaling force when the second driving force characteristic is set is reduced. Therefore, even when the second driving force characteristic is set as described above, it is possible to prevent the driver from feeling a sense of insufficient driving force, a sense of discomfort with the acceleration, etc. Therefore, according to the vehicle control device of the present invention, the burden on the driver when operating the accelerator pedal can be appropriately reduced without degrading the drivability of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1It is a diagram used to illustrate the control content and problems of the existing technology. It is a diagram showing the driving force characteristics of the vehicle (the relationship between the accelerator opening and the target driving force) when the standard characteristics (equivalent to the first driving force characteristics in the present invention) are set, the driving force characteristics of the vehicle when the correction characteristics (equivalent to the second driving force characteristics in the present invention) are set, and the commonly used accelerator opening area.

[0023] Figure 2 This diagram explains the control content and problems of the conventional technology and shows changes in the normal accelerator opening range and the reaction force (pedal load) of the accelerator pedal operated by the driver when the standard characteristic is changed to the modified characteristic.

[0024] Figure 3 This is a diagram showing an example of a structure and a control system of a vehicle to be controlled by the vehicle control device of the present invention.

[0025] Figure 4 This is a diagram for illustrating the structure of the accelerator pedal and reaction force actuator of a vehicle that is a control object in the vehicle control device of the present invention, and is a diagram showing a split-type reaction force actuator in which an accordion-type accelerator pedal body and a sensor part and a reaction force generating part of the reaction force actuator are separately formed.

[0026] Figure 5 This is a diagram for illustrating the structure of the accelerator pedal and reaction force actuator of a vehicle that is a control object in the vehicle control device of the present invention. It is a diagram showing a split-type reaction force actuator in which the sensor part of the accordion-type accelerator pedal and the reaction force generating part of the reaction force actuator are formed as one body, and the reaction force generating part of the accordion-type accelerator pedal body and the reaction force actuator are formed separately.

[0027] Figure 6 This is a diagram for illustrating the structure of the accelerator pedal and reaction force actuator of a vehicle that serves as a control object in the vehicle control device of the present invention. It is a diagram showing an integrated reaction force actuator in which an accordion-type accelerator pedal body and a sensor portion and a reaction force generating portion of the reaction force actuator are formed as one body, and the rod of the accelerator pedal and the rod of the reaction force actuator are used as both.

[0028] Figure 7 This is a diagram for illustrating the structure of the accelerator pedal and reaction force actuator of a vehicle that is a control object in the vehicle control device of the present invention. It is a diagram of an integrated reaction force actuator in which an accordion-type accelerator pedal body, a sensor portion, and a reaction force generating portion of the reaction force actuator are formed as one body, and an accelerator pedal rod and a reaction force actuator rod are separately provided.

[0029] Figure 8 This is a diagram for illustrating the structure of the accelerator pedal and reaction force actuator of a vehicle that is a control object in the vehicle control device of the present invention, and is a diagram of an integrated reaction force actuator in which the sensor part of a hanging (suspension) accelerator pedal and the reaction force generating part of the reaction force actuator are formed as one.

[0030] Figure 9 This is a flowchart for illustrating an example of control performed by the control device of the vehicle of the present invention (an example of reducing the difference between the ratio of the vehicle acceleration to the pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration to the pedaling force when the second driving force characteristic is set by increasing the ratio of the increase in the target driving force to the increase in the accelerator opening under the second driving force characteristic).

[0031] Figure 10 It is used to illustrate the execution of Figure 9 FIG. 1 is a diagram showing correction (driving force characteristic correction control) of the vehicle driving force characteristic (relationship between accelerator opening and target driving force) in the case of the control shown in the flowchart of FIG.

[0032] Figure 11 Is used to illustrate the execution of Figure 9 A time chart showing changes in the normal accelerator opening range, changes in the accelerator pedal load, vehicle acceleration in the normal accelerator opening range, and a gradient of change (jerk) in vehicle acceleration under the control shown in the flowchart.

[0033] Figure 12 This is a time chart for explaining the vehicle acceleration corresponding to the operation speed of the driver's depression operation on the accelerator pedal, the change gradient of the vehicle acceleration (jerk), and the relationship between the change gradient of the vehicle acceleration and the reaction force of the accelerator pedal (pedal load).

[0034] Figure 13 This is a diagram for explaining changes in the reaction force (pedal load) of the accelerator pedal felt by the driver due to differences in physique (foot size).

[0035] Figure 14 This is a diagram showing an image of a reaction force (pedal load) of an accelerator pedal being changed using a reaction force actuator.

[0036] Figure 15This is a flowchart for illustrating another example of control performed by the control device of the vehicle of the present invention (an example of reducing the difference between the ratio of vehicle acceleration to pedal force when the "first driving force characteristic" is set and the ratio of vehicle acceleration to pedal force when the "second driving force characteristic" is set by using a "reaction force actuator" to reduce the reaction force of the accelerator pedal).

[0037] Figure 16 Is used to illustrate the execution of Figure 15 FIG. 1 is a diagram showing correction of the vehicle driving force characteristics (relationship between the accelerator opening and the target driving force) in the case of the control shown in the flowchart of FIG.

[0038] Figure 17 Is used to execute the Figure 15 A time chart illustrating the vehicle acceleration and the gradient of change (jerk) of the vehicle acceleration in the normal accelerator opening range in the case of the control shown in the flowchart.

[0039] Figure 18 This is a time chart showing the vehicle acceleration and the gradient of change (jerk) of the vehicle acceleration in the normal accelerator opening range when the driving force characteristic correction control of the present invention is not performed (when the control content of the conventional technology is performed) as a comparative example. DETAILED DESCRIPTION

[0040] The embodiment of the present invention will be described with reference to the drawings. The embodiment described below is merely an example of a specific embodiment of the present invention and does not limit the present invention.

[0041] exist Figure 3 1 shows an example of a drive system and a control system of a vehicle Ve that is a control target in the embodiment of the present invention. Figure 3 The illustrated vehicle Ve typically includes a driving force source (PWR) 1 , drive wheels 2 , an accelerator pedal 3 , a seat (SEAT) 4 , a detection unit 5 , and a controller (ECU) 6 .

[0042] The driving force source 1 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine, and is configured so that operating states such as output adjustment and starting and stopping are electrically controlled. If the driving force source 1 is a gasoline engine, the throttle valve opening, fuel supply or injection amount, ignition start and stop, and ignition timing are all electrically controlled. Alternatively, if the driving force source 1 is a diesel engine, the fuel injection amount, fuel injection timing, or, for example, the throttle valve opening in the EGR system are all electrically controlled. Alternatively, the driving force source 1 in the embodiments of the present invention may be, for example, an electric motor such as a permanent magnet synchronous motor or an induction motor. In this case, the electric motor may be, for example, a so-called motor generator, which functions both as a prime mover driven by power supply to output motor torque and as a generator driven by receiving external torque to generate electricity. If it is a motor generator, the speed, torque, and switching between the prime mover and generator functions are all electrically controlled.

[0043] The driving wheel 2 generates the driving force of the vehicle Ve by transmitting the driving torque output by the driving force source 1. Figure 3 In the embodiment shown, the driving wheels 2 are connected to the driving force source 1 via the transmission 7, the differential 8 and the drive shaft 9. In addition, the vehicle Ve in the embodiment of the present invention may also be as follows Figure 3 As in the embodiment shown in FIG. 1 , the vehicle Ve may be a front-wheel drive vehicle that transmits driving torque to the front wheels, generating driving force at the front wheels. Alternatively, the vehicle Ve may be a rear-wheel drive vehicle that transmits driving torque to the rear wheels via a propeller shaft (not shown), generating driving force at the rear wheels. Alternatively, the vehicle Ve may be a four-wheel drive vehicle that includes a transmission mechanism (not shown), transmits driving torque to both the front and rear wheels, and generates driving force at both the front and rear wheels.

[0044] In the embodiment of the present invention, the vehicle Ve, which is the control target, has a conventional configuration and includes an accelerator pedal 3, which the driver uses to adjust the driving force and accelerate the vehicle Ve. When the accelerator pedal 3 is depressed, the throttle position (e.g., the throttle opening of a gasoline engine or the fuel injection rate of a diesel engine) increases in accordance with the amount of operation (depression amount, accelerator opening, or accelerator position) of the accelerator pedal 3. As a result, the driving torque increases, and the driving force of the vehicle Ve increases. Conversely, when the accelerator pedal 3 is depressed again (decrease in the amount of operation, or decrease in the accelerator opening or accelerator position), the throttle position decreases in accordance with the amount of operation of the accelerator pedal 3. As a result, the driving torque decreases, and the driving force of the vehicle Ve decreases. Furthermore, as the driving force decreases, the braking force of the vehicle Ve increases. Specifically, when the accelerator pedal 3 is depressed again, so-called engine braking takes effect, increasing the braking force of the vehicle Ve. For example, the friction torque and pumping losses of the internal combustion engine act as resistance (braking torque) against the driving torque, generating a braking force on the vehicle Ve. Alternatively, when an electric motor is mounted as the driving force source 1 , the electric motor functions as a regenerative brake to generate a regenerative braking force in the vehicle Ve.

[0045] As described above, the accelerator pedal 3 adjusts the driving force and braking force of the vehicle Ve through the operation of the driver. As described later, the accelerator pedal 3 is provided with an accelerator position sensor 5a for detecting the operation amount and operation speed of the driver's stepping operation on the accelerator pedal 3. The operation amount or stepping amount of the accelerator pedal 3 (i.e., accelerator opening, accelerator position) can be detected by the accelerator position sensor 5a. In addition, by detecting the operation speed of the accelerator pedal 3 based on the operation amount of the accelerator pedal 3 detected by the accelerator position sensor 5a, the operation state and operation direction of the accelerator pedal 3 by the driver can be determined. That is, it can be determined whether the driver is in a state of stepping on the accelerator pedal 3 or in a state of returning the stepping of the accelerator pedal 3. In addition, the accelerator pedal 3 in the embodiment of the present invention can also be provided with a pedal force sensor 5b, a surface pressure sensor 5g, etc. as described later.

[0046] Furthermore, in the embodiment of the present invention, the vehicle Ve as the control object may also be provided with a reaction force actuator 10 for the accelerator pedal 3. The reaction force actuator 10 is a device for changing and controlling the reaction force of the accelerator pedal 3. In this case, the reaction force of the accelerator pedal 3 is a pedal load that resists the pedal force when the driver steps on the accelerator pedal 3. For example, Figure 4As shown, the reaction force actuator 10 includes a reaction force generating portion 10a and a rod 10b. The reaction force generating portion 10a is mounted on the dash panel 11. The reaction force generating portion 10a is composed of, for example, an electric actuator (not shown) or a hydraulic actuator (not shown), and transmits the reaction force (pedal load) to the accelerator pedal 3 via the rod 10b. Figure 4 The accelerator pedal 3 shown is a so-called organ-type accelerator pedal 3, which is mounted on the floor panel 12. The accelerator pedal 3 includes a pedal body 3a, a sensor portion 3b, and a rod 3c. The sensor portion 3b is provided with, for example, the above-mentioned accelerator position sensor 5a and pedal force sensor 5b. In addition, the sensor portion 3b is provided with a return spring (not shown) that generates a reaction force of the accelerator pedal 3. For example, the force of the return spring is transmitted to the pedal body 3a via the rod 3c as a reaction force of the accelerator pedal 3. And, the Figure 4 The reaction force actuator 10 shown is a split-type reaction force actuator 10 in which the pedal body 3 a and the sensor portion 3 b of the accelerator pedal 3 and the reaction force generating portion 10 a of the reaction force actuator 10 are separately formed.

[0047] In addition, the reaction force actuator 10 is not limited to the above-mentioned Figure 4 For example, Figure 5 As shown, the sensor portion 3b of the accelerator pedal 3 and the reaction force generating portion 10a of the reaction force actuator 10 may be formed integrally or integrally housed in a housing (not shown), or the pedal body 3a of the accelerator pedal 3 and the reaction force generating portion 10a of the reaction force actuator 10 may be formed separately. Figure 5 In the illustrated embodiment, the rod 3 c of the accelerator pedal 3 and the rod 10 b of the reaction force actuator 10 serve both.

[0048] In addition, for example Figure 6 As shown, the pedal body 3a of the organ-type accelerator pedal 3 and the sensor part 3b and the reaction force generating part 10a of the reaction force actuator 10 may be formed as one or accommodated in a housing (not shown) as one, and the rod 3c of the accelerator pedal 3 and the rod 10b of the reaction force actuator 10 may be used as an integrated reaction force actuator 10. Figure 6 In the illustrated embodiment, the reaction force actuator 10 is mounted to a floor panel 12 .

[0049] In addition, for example Figure 7As shown, the pedal body 3a of the accelerator pedal 3 and the sensor part 3b and the reaction force generating part 10a of the reaction force actuator 10 may be formed integrally or integrally accommodated in a housing (not shown), and the rod 3c of the accelerator pedal 3 and the rod 10b of the reaction force actuator 10 may be separately provided as an integrated reaction force actuator 10. Figure 7 In the illustrated embodiment, the reaction force actuator 10 is mounted to a floor panel 12 .

[0050] And, for example Figure 8 As shown, the sensor portion 3b of the accelerator pedal 3 and the reaction force generating portion 10a of the reaction force actuator 10 may be formed integrally or integrally accommodated in a housing (not shown) of a so-called hanging type (or suspended type) reaction force actuator 10. Figure 8 In the illustrated embodiment, the reaction force actuator 10 is mounted on the floor panel 12 together with the sensor portion 3b of the accelerator pedal 3. Thus, in the vehicle control device according to the embodiment of the present invention, the type of accelerator pedal 3 is irrelevant as long as the reaction force actuator 10 is provided and the reaction force (pedal load) of the accelerator pedal 3 can be controlled. In other words, both a so-called organ-type accelerator pedal 3 and a so-called suspended (suspended) accelerator pedal 3 can be controlled by the vehicle control device according to the embodiment of the present invention.

[0051] Seat 4 is the driver's seat, located directly behind the steering wheel (not shown) and accelerator pedal 3. As will be described later, a vehicle control device according to an embodiment of the present invention estimates the ankle loads acting on the driver's ankles and legs based on the driver's posture while seated in the driver's seat, i.e., seat 4. To this end, seat 4 is provided with a seat position sensor 5c and a seating sensor 5d, as will be described later.

[0052] The detection unit 5 is a device or apparatus for acquiring various data and information required for controlling the vehicle Ve. It includes, for example, a power supply, a microcomputer, sensors, and an input / output interface. Specifically, the detection unit 5 includes an accelerator position sensor 5a that detects the amount of operation of the accelerator pedal 3 (i.e., the accelerator position or accelerator opening), and a pedal force sensor 5b that detects the driver's pedal force (pedal load) on the accelerator pedal 3. Furthermore, the detection unit 5 includes a seat position sensor 5c that detects the position and state of movable parts in the driver's seat (seat 4) (i.e., the seat position), and a seat occupancy sensor 5d that detects the presence of a driver in the driver's seat (seat 4) and the driver's seat position or state. Furthermore, the detection unit 5 includes, for example, a wheel speed sensor 5e that detects the rotational speed of each wheel, and an acceleration sensor 5f that detects the acceleration of the vehicle Ve (particularly the fore-aft acceleration). The vehicle may also include the aforementioned pedal force sensor 5b and a surface pressure sensor 5g for estimating the driver's accelerator pedal 3 depression state, foot size, or foot dimensions, or the aforementioned seat position sensor 5c and seat occupancy sensor 5d, as well as an image recognition camera 5h for estimating the driver's physique and driving posture. Furthermore, a human sensor (not shown) utilizing infrared, visible light, or ultrasonic waves, or a thermal imaging camera (not shown), may also be included. The detection unit 5 is electrically connected to a controller 6 (described later) and outputs electrical signals corresponding to detection values or calculated values of the various sensors, devices, and apparatuses described above as detection data to the controller 6.

[0053] The controller 6 is, for example, an electronic control device composed mainly of a microcomputer. For example, the controller 6 in the embodiment of the present invention mainly controls the actions of the driving force source 1 and the transmission 7, respectively. In addition, when a reaction force actuator 10 as described above is provided, the controller 6 controls the actions of the reaction force actuator 10. Various data detected or calculated by the above-mentioned detection unit 5 are input to the controller 6. The controller 6 performs calculations using the various input data and pre-stored data, calculation formulas, etc. At the same time, the controller 6 is configured to output its calculation results as control command signals to control the actions of the driving force source 1 and the transmission 7 and the reaction force actuator 10, etc., respectively, as described above.

[0054] For example, the controller 6 calculates the target driving force (or target driving torque) of the driving force source 1 based on the operation amount of the accelerator pedal 3 detected by the accelerator position sensor 5a and the vehicle speed calculated based on the detection value of the wheel speed sensor 5e. And, based on the target driving force, the output of the driving force source 1 is controlled. In addition, the controller 6 controls the gear ratio (or gear shift) set by the transmission 7. Furthermore, the controller 6 estimates the posture or posture of the driver in the driver's seat based on the detection value or detection result of the pedal force sensor 5b, the seat position sensor 5c, etc., and estimates the ankle load of the driver based on the posture or posture of the driver. And, based on the estimated ankle load of the driver, the controller 6 selectively sets the first driving force characteristic and the second driving force characteristic as the driving force characteristics of the target driving force of the vehicle Ve as described later. In addition, in Figure 3 Although an example in which one controller 6 is provided is shown, a plurality of controllers 6 may be provided, for example, according to the devices or equipment to be controlled or according to the control content.

[0055] As described above, the purpose of the vehicle control device in the embodiment of the present invention is to reduce the burden on the driver in the accelerator pedal 3 without degrading the drivability of the vehicle Ve. An example of the control performed by the controller 6 to achieve this purpose is shown in FIG. Figure 9 Flowchart of the process.

[0056] Figure 9 The control content shown in the flowchart is an example of the control performed by the "acceleration feeling maintaining unit" in an embodiment of the present invention, and shows the following control example: by increasing the ratio of the increase in the target driving force to the increase in the accelerator opening under the second driving force characteristic, the difference between the ratio of the vehicle acceleration to the pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration to the pedaling force when the second driving force characteristic is set is reduced.

[0057] exist Figure 9 In the flowchart, first, in step S1, the body shape (driver's driving posture) of the driver sitting in the driver's seat, that is, the seat 4 is detected. For example, the driver's driving posture, physique, sitting position, seat position, foot size, etc. are detected or known.

[0058] In step S2, the magnitude of the driver's ankle load is estimated. Ankle load refers to the load acting on the driver's ankles and legs when the driver steps on accelerator pedal 3. More specifically, in embodiments of the present invention, ankle load is defined as the load on the driver's ankle and leg muscles. As previously mentioned, when operating accelerator pedal 3, the driver typically steps on accelerator pedal 3 with their heel resting on the floor and their sole resting on accelerator pedal 3. When the ankle angle between the driver's sole and shin is small, the load on the ankle and leg muscles is greater than when the ankle angle is large. Therefore, in the vehicle control device of embodiments of the present invention, the driver's ankle angle, as described above, is calculated based on the driver's physique, foot size, driving posture, and other factors detected in step S1. The magnitude of the ankle load is then estimated based on this ankle angle. For example, the magnitude of the ankle load is quantitatively assessed based on the calculated ankle angle. The smaller the ankle angle, the greater the ankle load is estimated to be.

[0059] In step S3, a determination is made as to whether a driving force correction is necessary. Specifically, a determination is made as to whether the ankle load estimated in step S2 is above a correction determination threshold. The correction determination threshold is a threshold value pre-set as a threshold for determining whether a correction of the driving force characteristic (driving force characteristic correction control) is necessary. The driving force characteristic specifies a target driving force corresponding to the amount of operation of the accelerator pedal 3 (hereinafter referred to as the accelerator opening). Furthermore, in the vehicle control device according to an embodiment of the present invention, a first driving force characteristic and a second driving force characteristic are selectively set as the driving force characteristics of the vehicle Ve. The first driving force characteristic is a standard or reference driving force characteristic, and the target driving force specified by the second driving force characteristic is smaller than the target driving force specified by the first driving force characteristic. Normally, or at the start of control, the standard first driving force characteristic is selected and set as the driving force characteristic of the vehicle Ve. The second driving force characteristic is selected and set by correcting the standard first driving force characteristic. Therefore, if the estimated ankle load is smaller than the correction determination threshold, it is determined that the ankle load is of the standard magnitude and that correction of the driving force characteristic is not necessary. That is, the first driving force characteristic is set as the driving force characteristic of the vehicle Ve. If the estimated ankle load exceeds the correction determination threshold, it is determined that the driving force characteristic needs to be corrected. In other words, it is determined that the driving force characteristic of the vehicle Ve needs to be changed from the first driving force characteristic to the second driving force characteristic.

[0060] The first driving force characteristic is set as a standard driving force characteristic, while the second driving force characteristic is set to a driving force characteristic that can reduce the load on the driver's ankles. In addition, the second driving force characteristic is set in the normal accelerator opening range. Figure 10As shown in FIG, the frequently used accelerator opening range is determined to be at least a portion of the accelerator opening range that is frequently used in the entire accelerator opening range from fully closed (0) to fully open. Figure 10 In the embodiment shown, a portion of the accelerator opening range from the accelerator opening APO1 to the accelerator opening APO2 that is larger than the accelerator opening APO1 is set as the normal accelerator opening range. Figure 10 , the driving force characteristic represented by characteristic line DC1 (dashed line) is the first driving force characteristic, and the driving force characteristic represented by characteristic line DC2 (solid line) is the second driving force characteristic. Characteristic line DC0 (dashed line) represents the driving force characteristic when the driving force characteristic correction control in the embodiment of the present invention is not performed (conventional technology).

[0061] If a negative decision is made in step S3 because the estimated "ankle load" is smaller than the correction determination threshold, that is, if it is determined that the driving force characteristic does not need to be corrected, the subsequent control is not executed and the current control is temporarily terminated. Figure 9 If an affirmative decision is made in step S3 because the estimated "ankle load" is equal to or greater than the correction determination threshold, that is, if it is determined that the driving force characteristics need to be corrected, the routine proceeds to step S4.

[0062] In step S4, the target driving force at the accelerator opening APO1 is calculated. Figure 10 As shown, the accelerator opening APO1 is the accelerator opening that serves as the starting point (or lower limit) of the normal accelerator opening range. That is, the target driving force at the accelerator opening APO1 is the target driving force specified by the second driving force characteristic, and is the minimum target driving force that can reduce the load on the driver's ankles. Therefore, the target driving force at the accelerator opening APO1 in this case becomes smaller than the target driving force calculated corresponding to the accelerator opening APO1 when the first driving force characteristic is set. Such a minimum target driving force that can reduce the load on the driver's ankles can be obtained, for example, by the same method as in the past. Alternatively, it can be pre-set using an actual vehicle based on the results of a driving test, an analytical result obtained by simulation, etc. As described later, in the driving force characteristic correction control of an embodiment of the present invention, the second driving force characteristic is set using the target driving force at the accelerator opening APO1 as the starting point.

[0063] In step S5, the load change of the accelerator pedal 3 is calculated. In this case, the load change of the accelerator pedal 3 is the change in the reaction force of the accelerator pedal 3 (hereinafter referred to as pedal load) felt by the driver as the driving force characteristics of the vehicle Ve change from the first driving force characteristics to the second driving force characteristics. Specifically, Figure 11As shown in the time chart, the pedal load starts to increase at time t1, and continues to increase after time t2 until the accelerator opening is fully opened at time t5. In addition, by changing the driving force characteristics of vehicle Ve from the first driving force characteristics to the second driving force characteristics, the accelerator opening range from accelerator opening APO1 to accelerator opening APO2 is set as the normal accelerator opening range. That is, when the second driving force characteristics are set as the driving force characteristics of vehicle Ve, as shown in FIG. Figure 11 As shown by the upward dotted arrow in FIG, the area of the commonly used accelerator opening changes in the direction of increasing the accelerator opening. Figure 11 As indicated by the upward solid arrow, the pedal load corresponding to the predetermined normal accelerator opening increases. The difference between the pedal load before the increase and the pedal load corresponding to the increased accelerator opening APO1 is the load change on the accelerator pedal 3 calculated in step S5. Therefore, the load change on the accelerator pedal 3 can be determined by calculating the increase in the pedal load from time t2 when the predetermined normal accelerator opening is reached to time t3 when the accelerator opening reaches APO1.

[0064] Then, in step S6, a driving force correction amount in the normal accelerator opening range is calculated to correct the driving force characteristics of vehicle Ve. That is, driving force characteristic correction control is performed, and the driving force characteristics of vehicle Ve are changed from the first driving force characteristic to the second driving force characteristic. Specifically, as described above, the target driving force calculated based on the accelerator opening when the second driving force characteristic is set is reduced compared to the target driving force calculated based on the accelerator opening when the first driving force characteristic is set. At the same time, the second driving force characteristic is set so that the difference between the ratio of the vehicle acceleration generated in response to the driver's pedaling force relative to the pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration generated in response to the driver's pedaling force relative to the pedaling force when the second driving force characteristic is set is reduced. That is, the driving force correction amount in the normal accelerator opening range is calculated.

[0065] More specifically, in the normal accelerator opening range, the second driving force characteristic is set so that the ratio of the increase in the target driving force under the second driving force characteristic to the increase in the accelerator opening (ie Figure 10 The slope D of the characteristic line DC1 shown in FIG. 1 is the ratio of the increase in the target driving force to the increase in the accelerator opening under the first driving force characteristic (ie, Figure 10 The slope C) of the characteristic line DC1 shown is large.

[0066] The driving force correction amount in the above-mentioned common accelerator opening area is calculated, for example, by utilizing the change gradient of the vehicle acceleration (front and rear acceleration of the vehicle Ve) that changes in correspondence with the driver's stepping operation of the accelerator pedal 3, that is, the jerk of the vehicle Ve. When the driver steps on the accelerator pedal 3, the vehicle acceleration changes in accordance with the stepping operation. In addition, the jerk of the vehicle Ve corresponding to the operation speed of the stepping operation is generated. The jerk of the vehicle Ve that the driver feels as natural without feeling any sense of incongruity changes according to the pedal load felt by the driver. For example, when the pedal load felt by the driver is of a standard (medium) size, the jerk of the vehicle Ve that the driver feels as natural changes. Figure 12 The time diagram of the vehicle acceleration is represented by the slope of the acceleration line AL1 (solid line) during the period from time t11 to time t12. When the pedal load felt by the driver is greater than the standard pedal load, the jerk of the vehicle Ve that the driver feels as natural is Figure 12 The time diagram of the vehicle acceleration is represented by the slope of the acceleration line AL2 (dash-dotted line) during the period from time t11 to time t12. In addition, when the pedal load felt by the driver is smaller than the standard pedal load, the jerk of the vehicle Ve that the driver feels as natural is Figure 12 The slope of the acceleration line AL3 (two-dot chain line) representing the change in vehicle acceleration in the time diagram during the period from time t11 to time t12 is shown. The greater the pedal load felt by the driver, the greater the jerk of the vehicle Ve that the driver feels as natural. Therefore, in a case where the pedal load felt by the driver is greater than the standard, by setting the driving force characteristics (or acceleration characteristics) of the vehicle Ve to a jerk greater than the standard, the driver can feel a natural sense of acceleration without feeling any discomfort. In addition, in a case where the pedal load felt by the driver is smaller than the standard, by setting the driving force characteristics (or acceleration characteristics) of the vehicle Ve to a jerk smaller than the standard, the driver can feel a natural sense of acceleration without feeling any discomfort.

[0067] Therefore, in step S6, the pedal load felt by the driver is taken into consideration and the driving force correction amount in the normal accelerator opening range is calculated so as to obtain the jerk of the vehicle Ve that the driver feels natural. In addition, the pedal load felt by the driver varies depending on the driver's physique and foot size. For example, Figure 13As shown by the dashed line in the figure, if the driver is small and has small feet, the pedal load felt by the driver increases in accordance with the accelerator opening, that is, the amount of operation the driver performs when operating the accelerator pedal. If the driver is small and has smaller feet than standard, when the driver steps on the accelerator pedal 3 with the sole of the foot, using the heel as a fulcrum, the point of application of the pedal force is closer to the fulcrum on the heel side than with standard feet. Therefore, the distance between the point of application of the pedal force and the fulcrum is shortened, correspondingly increasing the pedal load felt by the driver. Therefore, in the driving force characteristic correction control of the embodiment of the present invention, the pedal load, which varies according to the driver's physique and foot size, is also taken into account, and the driving force correction amount in the normal accelerator opening range is calculated to achieve a jerk of the vehicle Ve that the driver feels natural.

[0068] By calculating the driving force correction amount in the normal accelerator opening range as described above, the second driving force characteristic is set as the driving force characteristic of the vehicle Ve, and the jerk of the vehicle Ve generated in the normal accelerator opening range changes. Figure 11 As shown in the time chart, in the normal accelerator opening range where the accelerator opening increases from time t3 to time t4, the slope E of the vehicle acceleration represented by the dot-dash line represents the jerk of the vehicle Ve when the first driving force characteristic is set as the driving force characteristic. The slope F of the vehicle acceleration represented by the solid line represents the jerk of the vehicle Ve when the second driving force characteristic is set as the driving force characteristic. Figure 11 In the time chart of , the vehicle acceleration slope F becomes larger than the vehicle acceleration slope E. That is, the jerk of the vehicle Ve when the second driving force characteristic is set becomes larger than the jerk of the vehicle Ve when the first driving force characteristic is set.

[0069] also, Figure 11 The time t3 in the time chart is the point at which the accelerator opening reaches the accelerator opening APO1, which is the starting point of the normal accelerator opening range. As mentioned above, when the second driving force characteristic is set, the target driving force calculated corresponding to the accelerator opening APO1 is lower than the target driving force calculated corresponding to the accelerator opening APO1 when the first driving force characteristic is set. Therefore, Figure 11As shown in the time diagram, the vehicle acceleration at time t3 when the second driving force characteristic is set is smaller than the vehicle acceleration when the first driving force characteristic is set. That is, in the normal accelerator opening range, the second driving force characteristic is set, in which the target driving force is smaller than the first driving force characteristic. By setting this second driving force characteristic in the normal accelerator opening range, the driver will step on the accelerator pedal 3 more or harder than when operating with the first driving force characteristic to obtain driving force. As a result, the opportunity and frequency of operating the accelerator pedal 3 with a small ankle angle are reduced. Therefore, the driver's ankle load when stepping on the accelerator pedal 3 is reduced.

[0070] In addition, if Figure 11 As shown in the time chart, in the second driving force characteristic, by making the target driving force smaller than the target driving force under the first driving force characteristic at time t3, when the accelerator opening reaches accelerator opening APO1, the resulting vehicle acceleration also decreases. Then, by making the jerk greater than the jerk under the first driving force characteristic, the difference between the vehicle acceleration when the second driving force characteristic is set and the vehicle acceleration when the first driving force characteristic is set gradually decreases from time t3 to time t4, when the normal accelerator opening range is reached. Then, from time t4, when the normal accelerator opening range ends, to time t5, when the accelerator opening reaches full open or a predetermined accelerator opening greater than accelerator opening APO2, the vehicle acceleration when the second driving force characteristic is set matches the vehicle acceleration when the first driving force characteristic is set. Therefore, when the second driving force characteristic is set, although the magnitude of the jerk changes around time t5, the difference in jerk around time t5 is smaller than, for example, in a conventional case where the magnitude of the jerk does not change between the first and second driving force characteristics. Consequently, when the accelerator opening deviates from the normal accelerator opening range, the driver's discomfort caused by the increase in jerk variation due to the increase in driving force and acceleration of the vehicle Ve is suppressed.

[0071] When the driving force correction amount in the normal accelerator opening range is calculated in step S6 and the driving force characteristic of the vehicle Ve is corrected based on the driving force correction amount, that is, when the second driving force characteristic is set as the driving force characteristic of the vehicle Ve, the process is temporarily terminated. Figure 9 The routine is shown in the flowchart.

[0072] exist Figures 14 to 17 , another embodiment of the driving force characteristic correction control executed by the vehicle control device in the embodiment of the present invention is shown. As mentioned above, in the embodiment of the present invention, the vehicle Ve as the control object may also have a reaction force actuator 10 that can change and control the pedal load on the accelerator pedal 3. Figure 14 As shown, by using the reaction force actuator 10 , the pedal load when the driver operates the accelerator pedal 3 , that is, the reaction force of the accelerator pedal 3 can be arbitrarily changed.

[0073] exist Figure 15 The flowchart of FIG. 1 shows another example of control performed by the "acceleration feeling maintaining unit" in the embodiment of the present invention. This control example is to reduce the pedal load of the accelerator pedal 3 by using the reaction force actuator 10, thereby reducing the difference between the ratio of the vehicle acceleration to the pedal force when the first driving force characteristic is set and the ratio of the vehicle acceleration to the pedal force when the second driving force characteristic is set. In addition, Figure 15 Steps S11 to S15 in the flowchart are the same as those in the above Figure 9 The control contents of steps S1 to S5 in the flowchart are the same.

[0074] exist Figure 15 In the flowchart of Figure 9 After executing the control steps S11 to S15 in the same manner as in the embodiment shown in the flowchart, in step S16, the reaction force actuator 10 is controlled to change the pedal load of the accelerator pedal 3. Specifically, when the second driving force characteristic is set, the target driving force calculated based on the accelerator opening is reduced compared to the target driving force calculated based on the accelerator opening when the first driving force characteristic is set. At the same time, the pedal load of the accelerator pedal 3 is reduced to reduce the difference between the ratio of the vehicle acceleration generated in response to the driver's pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration generated in response to the driver's pedaling force when the second driving force characteristic is set.

[0075] More specifically, a second driving force characteristic is set in the normal accelerator opening range to reduce the target driving force calculated based on the accelerator opening. In this case, first, the target driving force at the accelerator opening APO1 is calculated. Figure 9 Similarly to the embodiment shown in the flowchart of , the target driving force at the accelerator opening APO1 is the minimum target driving force that is specified by the second driving force characteristic and can reduce the load on the driver's ankles. Therefore, the target driving force at the accelerator opening APO1 is smaller than the target driving force calculated corresponding to the accelerator opening APO1 when the first driving force characteristic is set. As mentioned above, the minimum target driving force that can reduce the load on the driver's ankles can be obtained, for example, by the same method as in the past. Alternatively, it can be pre-set using a real vehicle based on the results of driving experiments, analytical results achieved by simulation, etc. And, as Figure 16As shown in FIG, the target driving force at the accelerator opening APO1 is used as a starting point, and a second driving force characteristic having a characteristic line with a slope equal to that of the first driving force characteristic is set. Figure 16 , the driving force characteristics represented by the characteristic line DC11 (dashed line) are the first driving force characteristics, and the driving force characteristics represented by the characteristic line DC12 (solid line) are the second driving force characteristics.

[0076] The amount of reduction in the pedal load achieved by the reaction force actuator 10 is set based on, for example, the amount of change in the load of the accelerator pedal 3 calculated in step S15. Figure 17 As shown in the timing diagram, the pedal load when the driver steps on the accelerator pedal 3 begins to increase at time t11, and continues to increase after time t12 until the accelerator opening reaches full open or reaches a predetermined accelerator opening greater than accelerator opening APO2 at time t15. In addition, by changing the driving force characteristics of the vehicle Ve from the first driving force characteristics to the second driving force characteristics, the accelerator opening range from accelerator opening APO1 to accelerator opening APO2 is set as the normal accelerator opening range. That is, when the second driving force characteristics are set as the driving force characteristics of the vehicle Ve, as shown in FIG. Figure 17 As shown by the upward dashed arrow in FIG, the area of the commonly used accelerator opening changes toward the direction of increasing the accelerator opening. Figure 17 As shown by the upward solid arrow, the pedal load corresponding to the predetermined normal accelerator opening changes in the direction of increase. The difference between the pedal load before the increase and the pedal load corresponding to the accelerator opening APO1 after the increase is the load change of the accelerator pedal 3 calculated in step S15. Figure 17 In the embodiment shown in the time diagram, the reduction amount of the pedal load achieved by the reaction force actuator 10 is set to be equal to the change amount of the load of the accelerator pedal 3, that is, the change amount of the pedal load increased due to the change of the driving force characteristics of the vehicle Ve from the first driving force characteristics to the second driving force characteristics.

[0077] In addition, the amount of pedal load reduction achieved by the reaction force actuator 10 can also be appropriately set based on the estimated size of the driver's ankle load. For example, the larger the size of the driver's ankle load estimated in step S12, the greater the amount of pedal load reduction achieved by the reaction force actuator 10. As mentioned above, the pedal load felt by the driver varies depending on the driver's physique and foot size. Therefore, the driver's ankle load when the driver operates the accelerator pedal 3 also varies depending on the driver's physique and foot size. Therefore, by setting the amount of pedal load reduction achieved by the reaction force actuator 10 based on the size of the driver's ankle load estimated in step S12, it is possible to perform appropriate control of the reaction force actuator 10 that takes into account the driver's physique and foot size.

[0078] As described above, when the pedal load by the reaction force actuator 10 is reduced and the second driving force characteristic is set as the driving force characteristic of the vehicle Ve, the jerk of the vehicle Ve generated in the normal accelerator opening range does not change compared to the jerk of the vehicle Ve generated when the first driving force characteristic is set as the driving force characteristic of the vehicle Ve. Figure 17 As shown in the time chart, in the normal accelerator opening range where the accelerator opening increases from time t13 to time t14, the slope G of the vehicle acceleration represented by the dot-dash line represents the jerk of the vehicle Ve when the first driving force characteristic is set as the driving force characteristic. The slope H of the vehicle acceleration represented by the solid line represents the jerk of the vehicle Ve when the second driving force characteristic is set as the driving force characteristic. Figure 17 In the time chart of , the vehicle acceleration gradient G is equal to the vehicle acceleration gradient H. That is, the jerk of the vehicle Ve when the second driving force characteristic is set is equal to the jerk of the vehicle Ve when the first driving force characteristic is set.

[0079] also, Figure 17 The time t13 in the time chart is the point at which the accelerator opening reaches the accelerator opening APO1, which is the starting point of the normal accelerator opening range. As mentioned above, when the second driving force characteristic is set, the target driving force calculated corresponding to the accelerator opening APO1 is lower than the target driving force calculated corresponding to the accelerator opening APO1 when the first driving force characteristic is set. Therefore, Figure 17 As shown in the time chart of , the vehicle acceleration when the second driving force characteristic is set at time t13 is smaller than the vehicle acceleration when the first driving force characteristic is set.

[0080] In step S16, when the second driving force characteristic in which the predetermined target driving force is lower than the target driving force under the first driving force characteristic is set as the driving force characteristic of the vehicle Ve, and at the same time, the pedal load of the accelerator pedal 3 is reduced, the operation by the vehicle Ve is temporarily terminated. Figure 15 The flowchart represents the routine.

[0081] As described above, in the vehicle control device according to an embodiment of the present invention, the driver's ankle load is estimated when the driver steps on the accelerator pedal 3, particularly to reduce the load on the driver's ankles and leg muscles. Furthermore, the driving force characteristics of the vehicle Ve are set based on the magnitude of this estimated ankle load. If the estimated ankle load is a standard ankle load that is smaller than a correction determination threshold, a first driving force characteristic is set that specifies a standard target driving force. If the estimated ankle load exceeds the correction determination threshold, a second driving force characteristic is set that specifies a target driving force that is smaller than the first driving force characteristic. In other words, if a high ankle load exceeding the correction determination threshold is estimated, the driving force characteristics are corrected to reduce the specified target driving force. In this embodiment of the present invention, by setting the second driving force characteristic, the target driving force corresponding to at least the accelerator opening APO1, which serves as the starting point of the normal accelerator opening range, is lower than normal. By setting the second driving force characteristic in which the target driving force is reduced, the driver, when operating the accelerator pedal 3 to obtain driving force, tends to depress the accelerator pedal 3 more than when operating the accelerator pedal using the first driving force characteristic. As a result, the opportunity and frequency of operating the accelerator pedal 3 decreases in accelerator opening ranges where the ankle load increases due to a small ankle angle (a range where the amount of accelerator pedal 3 depressed is small). Therefore, the vehicle control device according to an embodiment of the present invention can reduce the driver's ankle load when depressing the accelerator pedal 3.

[0082] In addition, as a comparative example, Figure 18 The time chart shows the vehicle acceleration in the normal accelerator opening range and the gradient of the vehicle acceleration change (jerk) when the driving force characteristic correction control according to the embodiment of the present invention is not executed (for example, when the conventional control as described in the aforementioned Patent Document 1 is executed). In the conventional technology that does not execute the driving force characteristic correction control according to the embodiment of the present invention, Figure 18 In the time diagram, during the period from time t23 to time t24, the slope I of the vehicle acceleration represented by the dotted line represents the jerk of the vehicle Ve when the standard driving force characteristic (the first driving force characteristic in the embodiment of the present invention or the standard characteristic in the prior art) is set. The slope J of the vehicle acceleration represented by the solid line represents the jerk of the vehicle Ve when the driving force characteristic is corrected to reduce the load on the driver's ankles. When the driving force characteristic correction control in the embodiment of the present invention is not performed, as shown in FIG. Figure 18As shown in the time diagram of , the slope J of the vehicle acceleration is equal to the slope I of the vehicle acceleration. That is, even when the driving force characteristics are corrected, the jerk of the vehicle Ve does not change relative to the jerk of the vehicle Ve when the standard driving force characteristics before the correction are set. Therefore, when the driving force characteristics correction control in the embodiment of the present invention is not performed, although the driver's ankle load can be reduced by reducing the target driving force by correcting the driving force characteristics, it is possible to give the driver a feeling of insufficient driving force, a sense of discomfort with the acceleration, etc. That is, as mentioned above, the jerk of the vehicle Ve corresponding to the accelerator opening (that is, the speed of change of the driving force characteristics or the speed of change of the acceleration characteristics) remains unchanged, and the operation amount and pedaling force required for the stepping operation of the accelerator pedal 3 increase. Therefore, it is possible to give the driver a feeling of insufficient driving force and a sense of discomfort.

[0083] In contrast, in the control device for a vehicle according to an embodiment of the present invention, when the second driving force characteristic is set, that is, when the driving force characteristic is corrected so that the specified target driving force becomes smaller, the difference between the ratio of the vehicle acceleration (specifically, the front-rear acceleration of the vehicle Ve) generated in response to the pedaling force when the driver operates the accelerator pedal 3 under the first driving force characteristic to the pedaling force and the ratio of the vehicle acceleration generated in response to the pedaling force when the driver operates the accelerator pedal 3 under the second driving force characteristic to the pedaling force is reduced. That is, the ratio of the vehicle acceleration to the pedaling force controlled as described above will not differ significantly between the case where the first driving force characteristic is set and the case where the second driving force characteristic is set. For example, as determined by Figure 9 As in the embodiment shown in the flowchart of FIG, by making the ratio of the increase in the target driving force under the second driving force characteristic to the increase in the accelerator opening (i.e., the ratio of the increase in the target driving force under the second driving force characteristic to the increase in the accelerator opening) Figure 10 The slope D of the characteristic line DC2 shown in FIG. 1 is greater than the ratio of the increase in the target driving force to the increase in the accelerator opening under the first driving force characteristic (i.e., the ratio of the increase in the target driving force to the increase in the accelerator opening under the first driving force characteristic). Figure 10 The slope C) of the characteristic line DC1 shown is large, thereby reducing the difference as described above. Alternatively, by Figure 15 As in the embodiment shown in the flowchart of FIG, a reaction force actuator 10 is provided on the accelerator pedal 3, and the reaction force actuator 10 is controlled to reduce the reaction force to the driver's pedaling force, thereby reducing the above-mentioned difference.

[0084] Therefore, when the second driving force characteristic is set in order to reduce the load on the driver's ankles, the target driving force is made smaller than usual, and the ratio of the driving force (or acceleration) of the vehicle Ve generated corresponding to the driver's pedaling force becomes larger than when the driving force characteristic correction control in the embodiment of the present invention is not performed. That is, the difference between the ratio of the vehicle acceleration to the driver's pedaling force when the first driving force characteristic is set and the ratio of the vehicle acceleration to the driver's pedaling force when the second driving force characteristic is set becomes smaller. Therefore, even when the second driving force characteristic is set as described above, it is possible to prevent the driver from feeling a sense of insufficient driving force, a sense of discomfort with the acceleration, etc. Therefore, according to the control device for the vehicle in the embodiment of the present invention, the burden on the driver when operating the accelerator pedal 3 can be appropriately reduced without reducing the drivability of the vehicle Ve.

[0085] Description of Reference Signs

[0086] 1. Power source (PWR)

[0087] 2 drive wheels

[0088] 3 Accelerator pedal

[0089] 3a Pedal body (of the accelerator pedal)

[0090] 3b (Accelerator pedal) sensor

[0091] 3c (Accelerator pedal) lever

[0092] 4 Driver's seat (SEAT)

[0093] 5. Testing Department

[0094] 5a Accelerator position sensor (detection unit)

[0095] 5b (Detection unit) pedal force sensor

[0096] 5c Seat position sensor (detection unit)

[0097] 5d Seat sensor (detection unit)

[0098] 5e Wheel speed sensor (detection unit)

[0099] 5f Acceleration sensor (detection unit)

[0100] 5g Surface pressure sensor (detection part)

[0101] 5h Image recognition camera (detection department)

[0102] 6 Controller (ECU)

[0103] 7 Transmission

[0104] 8 Differential

[0105] 9 Drive shaft

[0106] 10 Reaction force actuator

[0107] 10a Reaction force generating portion (of reaction force actuator)

[0108] 10b Rod (of reaction force actuator)

[0109] 11 dash panel

[0110] 12 Floor Panels

[0111] Ve vehicle.

Claims

1. A vehicle control device, the vehicle comprising an accelerator pedal, wherein a reaction force of the accelerator pedal against a pedaling force during the pedaling operation increases as an accelerator opening corresponding to an operation amount of the accelerator pedal by a driver of the vehicle increases, the control device setting a driving force characteristic that specifies a target driving force corresponding to the accelerator opening, and estimating an ankle load acting on the driver's ankle and leg during the pedaling operation based on the posture of the driver seated in a driver's seat, setting a first driving force characteristic as a standard driving force characteristic when the estimated ankle load is smaller than a predetermined correction determination threshold value, and setting the first driving force characteristic when the estimated ankle load is smaller than a predetermined correction determination threshold value. When the ankle load is equal to or greater than the correction determination threshold, a second driving force characteristic is set as the driving force characteristic capable of reducing the ankle load, the target driving force is calculated based on the set first driving force characteristic or the second driving force characteristic and the accelerator opening, and the driving force of the vehicle is controlled based on the calculated target driving force, wherein the target driving force of the second driving force characteristic is smaller than the target driving force of the first driving force characteristic in a frequently used accelerator opening range, the frequently used accelerator opening range being defined as at least a portion of the accelerator opening range that is frequently used, from fully closed to fully open. The control device is characterized in that The control device includes a controller that estimates the ankle load, sets the first driving force characteristic or the second driving force characteristic, calculates the target driving force, and controls the driving force of the vehicle. The controller includes an acceleration feeling maintaining unit that reduces the target driving force calculated based on the accelerator opening when the second driving force characteristic is set, compared to the target driving force calculated based on the accelerator opening when the first driving force characteristic is set, and reduces the difference between the ratio of the acceleration of the vehicle generated corresponding to the pedaling force to the pedaling force when the first driving force characteristic is set and the ratio of the acceleration generated corresponding to the pedaling force to the pedaling force when the second driving force characteristic is set. The acceleration feeling maintaining unit reduces the difference by making the ratio of the increase in the target driving force under the second driving force characteristic to the increase in the accelerator opening greater than the ratio of the increase in the target driving force under the first driving force characteristic to the increase in the accelerator opening in the normal accelerator opening range.

2. The vehicle control device according to claim 1, wherein: The acceleration feeling maintaining unit sets a ratio of an increase in the target driving force to an increase in the accelerator opening under the second driving force characteristics based on the estimated magnitude of the ankle load.

3. The vehicle control device according to claim 1, wherein: The vehicle includes a reaction force actuator capable of changing and controlling the reaction force of the accelerator pedal. The acceleration feel maintaining unit reduces the difference by controlling the reaction force actuator to reduce the reaction force.

4. The vehicle control device according to claim 3, characterized in that: The acceleration feel maintaining unit sets an amount of reduction of the reaction force by the reaction force actuator based on the estimated magnitude of the ankle load.

Images