Vehicle control devices

Abstract

To provide a technique for performing warm-up control suitable for a driving mode.SOLUTION: A vehicular control device can change execution contents of warm-up control for warming up a driving force source of a vehicle, and in an automatic driving mode, the execution contents of the warm-up control are changed from those in a manual driving mode.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a vehicle control device used for a vehicle having an automatic driving mode and a manual driving mode.

Background Art

[0002] Conventionally, in a vehicle, a technique for determining the necessity of engine warming-up based on the coolant temperature of the engine or the catalyst temperature has been proposed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] <舍 However, the inventor of the present disclosure has found that the necessity of warming-up changes depending on whether the vehicle is running in the manual driving mode or the automatic driving mode. Therefore, it is desirable to perform warming-up control suitable for the driving mode.

Means for Solving the Problems

[0005] (1) According to one aspect of the present disclosure, there is provided a vehicle control device used for a vehicle having an automatic driving mode and a manual driving mode as driving modes. The vehicle control device can change the content of warming-up control for warming up a driving power source of the vehicle, and in the automatic driving mode, the content of the warming-up control is changed from the manual driving mode Furthermore, the vehicle control device strengthens or weakens the warm-up control compared to the manual driving mode, according to the vehicle's driving plan in the automatic driving mode. . According to this vehicle control device, warming-up control considering the driving mode can be performed. Also, The warming-up control can be strengthened or weakened according to the driving plan in the automatic driving mode. ( 2The vehicle control device may use at least one of the following as the travel plan: the planned travel distance, the planned travel time, and the planned vehicle speed. This vehicle control system allows for warm-up control that takes the driving plan into consideration. ( 3 ) According to another embodiment of this disclosure, a vehicle control device is provided for use in a vehicle having an automatic driving mode and a manual driving mode as driving modes. The vehicle control device can change the implementation of warm-up control for warming up the vehicle's power source, and in the automatic driving mode, the implementation of the warm-up control is changed from that in the manual driving mode. The vehicle control device will not perform the warm-up if the planned driving distance or planned driving time in the automatic driving mode is less than a preset threshold. 。 This vehicle control system allows for improved fuel efficiency by eliminating the need for engine warm-up. [Brief explanation of the drawing]

[0006] [Figure 1] An explanatory diagram showing the configuration of the vehicle's power transmission system. [Figure 2] An explanatory diagram showing a gear shift diagram and an example of its warm-up correction. [Figure 3] A flowchart illustrating the warm-up control process in the embodiment. [Modes for carrying out the invention]

[0007] Figure 1 is an explanatory diagram showing the configuration of the power transmission system of vehicle 100. This vehicle 100 has an automatic driving mode and a manual driving mode as driving modes. Vehicle 100 is equipped with an internal combustion engine 10, a transmission 30, a differential 40, a plurality of drive wheels 50, and a vehicle control device 80. The drive shaft 11 of the engine 10 is connected to the input shaft 31 of the transmission 30. The output shaft 32 of the transmission 30 is connected to the differential 40.

[0008] The accelerator pedal 61 is equipped with an accelerator position sensor 71 that measures the accelerator position ACC. The brake pedal 62 is equipped with a brake pedal sensor 72 that measures the amount of depression BRA of the brake pedal 62. The shift lever 63 is equipped with a shift position sensor 73 that measures the shift position LP. The engine 10 is equipped with a water temperature sensor 74 that measures its coolant temperature Tw. The transmission 30 is equipped with an oil temperature sensor 75 that measures the oil temperature To of its hydraulic circuit. Each of the drive wheels 50 is equipped with a wheel speed sensor 76. The measured values ​​from the various sensors 71 to 76 are input to the vehicle control device 80.

[0009] The vehicle control device 80 comprises a vehicle control unit 81, an automatic driving control unit 82, a driving mode setting unit 83, and a warm-up control unit 84. The vehicle control device 80 can be configured using one or more ECUs (Electronic Control Units). The ECU has a processor, RAM, and ROM, and a computer program is stored in the ROM. The functions of each unit 81 to 84 can be realized by the processor executing a computer program stored in a non-volatile storage medium. In addition, some of the functions of each unit 81 to 84 may be realized by hardware circuits.

[0010] The vehicle control unit 81 performs various controls for the operation of the vehicle 100, such as drive control, brake control, and steering angle control. The vehicle control unit 81 is used in both automatic and manual driving modes.

[0011] The automatic driving control unit 82 performs automatic driving of the vehicle 100. Specifically, the automatic driving control unit 82 transmits a drive force command value indicating the driving force of the drive unit (engine or motor), a brake command value indicating the operating state of the brake mechanism, and a steering angle command value indicating the steering angle of the wheels to the vehicle control unit 81. The vehicle control unit 81 performs control of each controlled mechanism according to the given command values.

[0012] In this disclosure, “autonomous driving” means driving in which all drive control, brake control, and steering angle control are performed automatically. In other words, the term “autonomous driving” includes autonomous driving from Level 3 to Level 5. Autonomous driving is performed according to a pre-set driving plan.

[0013] The driving mode setting unit 83 switches the driving mode of the vehicle 100 between manual driving mode and automatic driving mode. The driving mode can be switched, for example, by the occupant selecting from the options displayed on the display. Alternatively, the system may receive the driving mode switch from an external device via wireless communication.

[0014] The warm-up control unit 84 determines whether warm-up is necessary based on the coolant temperature Tw measured by the water temperature sensor 74 and the oil temperature To measured by the oil temperature sensor 75, and performs warm-up if necessary. When the engine 10 is cold, such as immediately after starting, the friction in various parts of the engine 10 and transmission 30 is greater than after warm-up is complete, which reduces the driving force of the vehicle 100. Therefore, the warm-up control unit 84 performs warm-up of the engine 10 and transmission 30 by correcting the gear lines.

[0015] Figure 2 is an explanatory diagram showing an example of a shift diagram and its warm-up correction. The horizontal axis represents the vehicle speed SP, and the vertical axis represents the accelerator opening ACC. The shift diagram is a diagram that shows the shift timing according to the accelerator opening ACC and the vehicle speed SP. The solid line indicates the upshift lines USn and USn+1 after the warm-up is completed (i.e., when the warm-up is not being performed). The area to the left of the upshift line USn is the area of the nth gear shift stage before the upshift, and the area to the right is the area of the (n + 1)th gear shift stage after the upshift. Each upshift line US indicates the condition for changing to a higher gear (i.e., a gear with a smaller gear ratio) as the vehicle speed SP increases. Each upshift line US has a rising portion RU that is substantially perpendicular to the horizontal axis of the vehicle speed SP, and an inclined portion SL with a smaller angle with the horizontal axis than the rising portion RU. The dashed line indicates the rising portion RUc of the upshift line for warm-up. The upshift line for warm-up is corrected so that the rising portion RU moves to the side of higher vehicle speeds. The correction amount Δ at this time is called the "warm-up correction amount Δ". Note that the inclined portion SL remains substantially the same even after the warm-up correction. By correcting the upshift line US in this way, the engine 10 operates at a higher rotation speed, so the warm-up of the power transmission system including the engine 10 can be performed. Also, the driving force of the vehicle 100 can be increased, and the responsiveness of the shift can be enhanced.

[0016] The warm-up correction amount Δ is given, for example, as a function f of the coolant water temperature Tw and the oil temperature To as follows. Δ = f(Twt - Tw, Tot - To) …(1) Here, Twt is the threshold temperature of the coolant water temperature, and Tot is the threshold temperature of the oil temperature. Normally, the warm-up correction amount Δ is set to be larger as the difference (Twt - Tw) from the threshold temperature Twt of the coolant water temperature is larger, and also larger as the difference (Tot - To) from the threshold temperature Tot of the oil temperature is larger. Also, when the coolant water temperature Tw is at or above the threshold temperature Twt and the oil temperature To is at or above the threshold temperature Tot, the warm-up correction amount Δ is zero. The threshold temperatures Twt and Tot are each set in the range of about 80°C to 90°C.

[0017] As described above, when the vehicle is cold, such as immediately after starting the engine 10, the driving force of the vehicle 100 decreases. However, when the vehicle 100 is traveling in the automatic driving mode, even if the driving force is slightly reduced, it is less likely to give the passengers an excessive sense of discomfort. Therefore, the need for warm-up is lower than when traveling in the manual driving mode. As will be described below, in this embodiment, warm-up control is executed in consideration of this point.

[0018] FIG. 3 is a flowchart showing the processing procedure of the warm-up control in the embodiment. The processing in FIG. 3 is executed, for example, when the vehicle 100 is started. Also, the processing in FIG. 3 may be executed at regular intervals after starting.

[0019] In step S10, the warm-up control unit 84 determines whether the warm-up condition is satisfied. The warm-up condition is a condition under which it is desirable for the power transmission system including the engine 10 to perform warm-up. Specifically, when at least one of the coolant temperature Tw and the oil temperature To is less than the respective threshold temperatures Twt and Tot, it is determined that the warm-up condition is satisfied. If the warm-up condition is not satisfied, warm-up is not performed, and the processing in FIG. 3 ends.

[0020] If it is determined that the warm-up condition is satisfied, the process proceeds to step S20, and the warm-up control unit 84 determines whether the current driving mode of the vehicle 100 is the automatic driving mode. If it is the manual driving mode, the process proceeds to step S30, and the warm-up control unit 84 performs warm-up correction of the gearshift line for the normal driving mode. This warm-up correction is performed by setting the warm-up correction amount Δ in FIG. 2 described above to a value suitable for the normal driving mode.

[0021] If the current driving mode of the vehicle 100 is automatic driving mode, the process proceeds to step S40, where the warm-up control unit 84 modifies the warm-up correction of the gear shift lines for normal driving mode for automatic driving mode. This modification is performed to strengthen or weaken the warm-up control compared to manual driving mode, depending on the driving plan in automatic driving mode. The driving plan in automatic driving mode may include a planned driving distance, planned driving time, and vehicle speed plan. It is preferable to modify the warm-up control using at least one of the planned driving distance, planned driving time, and vehicle speed plan.

[0022] Three possible methods for modifying the gear shift warm-up correction for automatic driving mode are as follows: <Modification Method C1> Strengthen the warm-up control compared to manual driving mode. Specifically, increase the warm-up correction amount Δ of the gear shift line to a value greater than that used in manual driving mode. <Modification Method C2> The warm-up control measures will be weakened compared to manual driving mode. Specifically, the warm-up correction amount Δ for the gear shift line will be made smaller than the value used in manual driving mode. <Method C3> Do not warm up the engine (disable warming up). That is, set the warm-up correction amount Δ of the gear shift line to zero.

[0023] Modification method C1 is applied, for example, when the driving plan includes high-torque, high-speed driving in a relatively short time after the vehicle 100 starts up. Specifically, if the time when the torque is above a threshold torque and the vehicle speed is above a threshold speed is scheduled to occur within a threshold time from the start up, it is preferable to apply modification method C1 to make the warm-up correction amount Δ of the gear shift line larger than the value used in manual driving mode. Note that the phrase "make the warm-up correction amount Δ larger than the value used in manual driving mode" means that when the coolant temperature Tw and oil temperature To are the same, the value of the warm-up correction amount Δ used in automatic driving mode is made larger than that used in manual driving mode.

[0024] Modification method C3 can be applied, for example, when the planned driving distance or driving time in the driving plan is smaller than a threshold. In these cases, there is little need to perform engine warm-up, so it is preferable not to perform engine warm-up at all. This can improve fuel efficiency.

[0025] Modification method C2 is applied when neither modification methods C1 nor C3 described above are applicable. In automatic driving mode, even if the driving force is slightly reduced, it is unlikely to cause excessive discomfort to the occupants, so the need for warming up is lower compared to when driving in manual driving mode. Therefore, unless you want to strengthen the warm-up control using modification method C1, it is preferable to weaken the warm-up control compared to manual driving mode to improve fuel efficiency. Modification method C3 described above can also be considered an example of weakening the warm-up control compared to manual driving mode. With modification method C3, warming up itself is not performed, so fuel efficiency can be further improved.

[0026] As described above, in this embodiment, the warm-up control procedures are changed in automatic driving mode from those in manual driving mode, so that warm-up appropriate for each driving mode can be performed.

[0027] In the above embodiment, the warm-up of a vehicle driven by an engine was described, but this disclosure is also applicable to the warm-up of a vehicle driven by a battery and an electric motor. In this case, for example, the warm-up condition is determined to be met when the battery temperature measured by the battery temperature sensor is above a preset threshold temperature. Furthermore, changes to the warm-up control can be made by changing the warm-up time, changing the warm-up intensity (amount of heating per unit time), or prohibiting warm-up. Battery warm-up is applicable to electric vehicles such as battery electric vehicles and hybrid vehicles having an engine and an electric motor.

[0028] Other forms: This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit. For example, this disclosure can also be implemented in the following forms (aspects). The technical features in the embodiments described above that correspond to the technical features in each of the forms described below can be replaced or combined as appropriate in order to solve some or all of the problems of this disclosure, or to achieve some or all of the effects of this disclosure. Furthermore, if such technical features are not described as essential in this specification, they can be deleted as appropriate.

[0029] This disclosure can also be implemented in various forms other than vehicle control devices and control methods. For example, it can be implemented in the form of a computer program that performs vehicle control, or a non-transitory storage medium on which the computer program is recorded. [Explanation of Symbols]

[0030] 10...Engine, 11...Drive shaft, 30...Transmission, 31...Input shaft, 32...Output shaft, 40...Differential, 50...Drive wheels, 61...Accelerator pedal, 62...Brake pedal, 63...Shift lever, 71...Accelerator position sensor, 72...Brake pedal sensor, 73...Shift position sensor, 74...Water temperature sensor, 75...Oil temperature sensor, 76...Wheel speed sensor, 80...Vehicle control device, 81...Vehicle control unit, 82...Automatic driving control unit, 83...Driving mode setting unit, 84...Warm-up control unit, 100...Vehicle

Claims

1. A vehicle control device used in a vehicle having an automatic driving mode and a manual driving mode as driving modes, The vehicle control device can change the content of the warm-up control performed for warming up the vehicle's power source, and in the automatic driving mode, the content of the warm-up control is changed from that in the manual driving mode. The vehicle control device is a vehicle control device that strengthens or weakens the warm-up control in accordance with the vehicle's driving plan in the automatic driving mode compared to the manual driving mode.

2. A vehicle control device according to claim 1, The vehicle control device uses at least one of the following as the travel plan: a planned travel distance, a planned travel time, and a planned vehicle speed.

3. A vehicle control device used in a vehicle having an automatic driving mode and a manual driving mode as driving modes, The vehicle control device can change the content of the warm-up control performed for warming up the vehicle's power source, and in the automatic driving mode, the content of the warm-up control is changed from that in the manual driving mode. The vehicle control device is a vehicle control device that does not perform the warm-up if the planned driving distance or planned driving time in the automatic driving mode is less than a preset threshold.

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