JP2022056958A - Vehicle control device - Google Patents

Abstract

To control an own vehicle so that fuel consumption in the future can be optimized.SOLUTION: A vehicle control device 1 comprises: a memorizing part 11 that memorizes a prediction model which predicts a speed of an own vehicle B in the future, shaft torque and an inter-vehicle distance between the own vehicle and a precedent vehicle, by setting variations of the shaft torque of an engine 4; a control input calculation part 122 that sequentially calculates variations of shaft torque at time points in the future as control input for minimizing evaluation function that is obtained by integrating functions to be integrated which include a term of fuel consumption of the own vehicle in which a speed of the own vehicle and the shaft torque which are predicted by the prediction model are set as variables, a term of variations of the shaft torque and a term of a deviation between the inter-vehicle distance and a target inter-vehicle distance; a target setting part 123 that sets sum of variations of shaft torque at the next time-point and shaft torque at a current time-point as target shaft torque at the next time-point; and an actuator control part 124 that controls an actuator mounted on the won vehicle so that the shaft torque is equal to the target shaft torque.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle control device that controls the speed of the own vehicle.

Patent Document 1 describes fuel consumption for generating a desired engine output torque by using an optimum fuel consumption rate map showing the relationship between the engine speed and the output torque, which is the optimum fuel consumption rate for the engine output. A technique for controlling the accelerator opening so that the rate is optimized is disclosed.

Japanese Unexamined Patent Publication No. 2008-49738

The above technique controls the accelerator opening so that the fuel consumption rate at the present time is optimized, and does not consider the future fuel consumption of the own vehicle. Therefore, it was not possible to control the own vehicle so that the future fuel consumption of the own vehicle would be optimized.

Therefore, the present invention has been made in view of these points, and an object thereof is to control the own vehicle so that at least the future fuel consumption of the own vehicle is optimized.

In the first aspect of the present invention, by determining the amount of change in the shaft torque output by the output shaft of the engine of the own vehicle, at least the future speed of the own vehicle, the shaft torque, and the own vehicle and the preceding vehicle A storage unit that stores a prediction model that predicts the distance between vehicles, a fuel consumption term of the fuel consumption of the own vehicle with the speed of the own vehicle predicted by the prediction model and the shaft torque as variables, and the prediction model. An integrand containing the torque term of the amount of change in the shaft torque predicted by the above prediction model and the distance deviation term of the deviation between the inter-vehicle distance and the target inter-vehicle distance predicted by the prediction model As a control input that minimizes the evaluation function obtained by integrating up to a time point, a control input calculation unit that sequentially calculates the amount of change in the shaft torque at each time point from the present time point to a time point ahead of a predetermined time, and the control The sum of the change amount of the shaft torque at the next time point of the present time and the shaft torque at the present time among the change amounts of the shaft torque at each time point calculated by the input calculation unit is the target at the next time point. It includes a target setting unit for setting as an axial torque, and an actuator control unit for controlling an actuator for controlling acceleration / deceleration of the own vehicle mounted on the own vehicle so that the shaft torque becomes the target shaft torque. A vehicle control device is provided.

For example, the control input calculation unit minimizes the evaluation function so that the inter-vehicle distance predicted by the prediction model does not become less than the minimum inter-vehicle distance smaller than the target inter-vehicle distance. Is calculated sequentially.

For example, the control input calculation unit minimizes the evaluation function obtained by integrating the integrand with the weight of the fuel consumption term larger than a predetermined value from the present time to a time point ahead of a predetermined time. The amount of change in the shaft torque is sequentially calculated.

For example, the control input calculation unit further includes the speed deviation term of the deviation between the speed of the own vehicle and the target speed in addition to the fuel consumption term, the torque term, and the distance deviation term. Is sequentially calculated from the present time to the time point ahead of a predetermined time, and the amount of change in the shaft torque that minimizes the evaluation function obtained by integrating the above.

For example, the target setting unit sets the acceleration of the own vehicle at the next time point predicted by the calculated change amount of the shaft torque as the target acceleration, and the actuator control unit sets the shaft torque as the target. The first actuator is controlled so as to have an axial torque, and the second actuator is controlled so that the acceleration of the own vehicle becomes the target acceleration.

According to the present invention, there is an effect that the own vehicle can be controlled so that at least the future fuel consumption of the own vehicle is optimized.

It is a figure which shows the structure of the own vehicle which concerns on embodiment. It is a figure which shows typically the control map which shows the relationship between the fuel injection amount, the shaft torque, and the rotation speed. It is a graph which plotted the time change of the inter-vehicle distance when the own vehicle is controlled by using a constraint condition. It is a graph which plotted the time change of the inter-vehicle distance which concerns on the comparative example which controlled the own vehicle without using a constraint condition. It is a flowchart which shows an example of the flow of the process executed by a vehicle control device.

[Structure of own vehicle B according to the embodiment]
The configuration of the own vehicle B according to the embodiment will be described with reference to FIG. 1. FIG. 1 is a diagram showing a configuration of the own vehicle B according to the embodiment. The own vehicle B according to the embodiment includes a vehicle control device 1, a sensor group 2, a fuel injection unit 31, a braking valve 32, an engine 4, and an air brake 5.

The sensor group 2 detects the state of the own vehicle B and the like. For example, the sensor group 2 includes an acceleration sensor that detects the acceleration of the own vehicle B. The sensor group 2 may include a speed sensor that detects the speed of the own vehicle B according to the rotation speed of the wheels of the own vehicle B. Further, the sensor group 2 includes a torque sensor that detects the shaft torque output by the output shaft of the engine 4. The sensor group 2 detects the preceding vehicle of the own vehicle B. For example, the sensor group 2 includes a camera that captures an image of the front of the vehicle B in the traveling direction or LIDAR (Light Detection and Ranging), and detects the distance between the vehicle B and the preceding vehicle. Further, the sensor group 2 can detect the speed and acceleration of the preceding vehicle by using the change in the inter-vehicle distance and the speed and acceleration of the own vehicle B. The sensor group 2 outputs the detection result to the vehicle control device 1.

The fuel injection unit 31 is a first actuator that injects fuel into the engine 4 of the own vehicle B. For example, the fuel injection unit 31 is controlled by the actuator control unit 124 of the vehicle control device 1 described later, and injects a predetermined amount of fuel into the cylinder of the engine 4.

The braking valve 32 is a second actuator that operates the air brake 5. The braking valve 32 is controlled by the actuator control unit 124 of the vehicle control device 1, which will be described later, and opens and closes the valve to operate the air brake 5.

The vehicle control device 1 automatically controls the speed of the own vehicle B so that the own vehicle B follows the preceding vehicle and travels by using the detection result detected by the sensor group 2. Hereinafter, the configuration of the vehicle control device 1 will be described.

[Configuration of vehicle control device 1]
The vehicle control device 1 includes a storage unit 11 and a control unit 12. The storage unit 11 is a storage medium including a ROM (Read Only Memory), a RAM (Random Access Memory), a hard disk, and the like. The storage unit 11 stores a program executed by the control unit 12.

The storage unit 11 stores a prediction model for predicting the future state of the own vehicle B. The state of the own vehicle B predicted by the prediction model is, for example, the speed of the own vehicle B, the shaft torque, and the inter-vehicle distance between the own vehicle B and the preceding vehicle. Further, the prediction model may predict, for example, the moving distance of the own vehicle B, the acceleration of the own vehicle B, the speed of the preceding vehicle, and the acceleration of the preceding vehicle as the situation around the own vehicle B. The vehicle control device 1 predicts the future state of the own vehicle B and the situation around the own vehicle B by using the prediction model by determining the amount of change in the shaft torque output by the output shaft of the engine 4 of the own vehicle B. can.

ｘ（ｔ）は、自車Ｂの移動距離、自車Ｂの速度、軸トルク、車間距離、先行車の速度及び先行車の加速度を含むベクトルである。また、ｘ（ｔ）は、自車Ｂの加速度を含んでもよい。ｕ（ｔ）は制御入力であり、本実施の形態では軸トルクの変化量である。 The prediction model according to this embodiment is represented by the equation of state of the following equation (1).

x (t) is a vector including the moving distance of the own vehicle B, the speed of the own vehicle B, the shaft torque, the inter-vehicle distance, the speed of the preceding vehicle, and the acceleration of the preceding vehicle. Further, x (t) may include the acceleration of the own vehicle B. u (t) is a control input, and in this embodiment, it is a change amount of the shaft torque.

ｖは、自車Ｂの速度である。ｉは、ギア比である。Ｔｏｒｑｕｅは、エンジン４の出力軸が出力する軸トルクである。本実施の形態に係るβ_１～β_５は、予め実験などにより定めた値である。また、β_１～β_５は、自車Ｂの走行中に取得した各種情報に基づいて適宜更新してもよい。なお、本実施の形態に係るθは、自車Ｂが走行する道路の勾配を示し、移動距離ｒの関数θ（ｒ（ｔ））である。 The storage unit 11 stores a function indicating the acceleration a in the traveling direction of the own vehicle B. The function indicating the acceleration a is expressed by the following equation (2).

v is the speed of the own vehicle B. i is the gear ratio. Torque is the shaft torque output by the output shaft of the engine 4. Β ₁ to β ₅ according to the present embodiment are values determined in advance by experiments or the like. Further, β ₁ to β ₅ may be appropriately updated based on various information acquired while the own vehicle B is traveling. Note that θ according to the present embodiment indicates the slope of the road on which the own vehicle B travels, and is a function θ (r (t)) of the travel distance r.

式（３）のｖ（ｔ）は、自車Ｂの速度である。ｖ_ｌ（ｔ）は、先行車の速度である。ａ_ｌ（ｔ）は、先行車の加速度である。記憶部１１は、式（１）の右辺を式（３）の右辺に置き換えた式を記憶してもよい。 The right side of the equation (1) is represented by the following equation (3) using the equation (2) showing the acceleration a and the time constant τ.

The v (t) of the equation (3) is the speed of the own vehicle B. v _l (t) is the speed of the preceding vehicle. a _l (t) is the acceleration of the preceding vehicle. The storage unit 11 may store an equation in which the right side of the equation (1) is replaced with the right side of the equation (3).

The storage unit 11 stores a control map showing the relationship between the fuel injection amount, the shaft torque, and the rotation speed of the engine 4 (hereinafter referred to as the rotation speed). FIG. 2 is a diagram schematically showing a control map showing the relationship between the fuel injection amount, the shaft torque, and the rotation speed. As shown in FIG. 2, the control map M is represented as a curved surface on a three-dimensional space about the fuel injection amount, the shaft torque, and the rotation speed. The vehicle control device 1 controls the injection of the fuel injection unit 31 by using the control map M. Specifically, the vehicle control device 1 uses the control map M to inject a predetermined amount of fuel into the fuel injection unit 31 so that the engine 4 of the running own vehicle B outputs a desired shaft torque. be able to. Further, the vehicle control device 1 can estimate the shaft torque output when a predetermined amount of fuel is injected into the fuel injection unit 31 by using the control map M.

The control unit 12 is a computing resource including a processor such as a CPU (Central Processing Unit). The control unit 12 realizes functions as an information acquisition unit 121, a control input calculation unit 122, a target setting unit 123, and an actuator control unit 124 by executing a program stored in the storage unit 11.

The information acquisition unit 121 acquires the detection result output by the sensor group 2. For example, the information acquisition unit 121 acquires the shaft torque and the inter-vehicle distance of the own vehicle B. Further, the information acquisition unit 121 acquires the speed and acceleration of the own vehicle B and the acceleration and speed of the preceding vehicle from the sensor group 2.

時点ｔ＋Ｔは、現時点ｔから所定時間先の時点である。以下、現時点ｔから所定時間先の時点ｔ＋Ｔまでの間を評価区間という。所定時間は、制御部１２の処理周期や最適化計算に係る時間に応じて適宜定めればよいが、具体的な値は例えば１分である。制御入力算出部１２２は、評価区間を所定間隔で離散化して、所定間隔ごとの各時点の軸トルクの変化量を算出する。所定間隔は、制御部１２の処理周期であり、例えば１ミリ秒である。 The control input calculation unit 122 sequentially calculates the amount of change in the shaft torque in the future as a control input that minimizes a predetermined evaluation function. The evaluation function is obtained by integrating a predetermined integrand from the present time to a time point ahead of a predetermined time. The evaluation function J according to the present embodiment is expressed by the following equation (4) using the integrand L.

The time point t + T is a time point predetermined time ahead of the current time t. Hereinafter, the period from the current time t to the time point t + T a predetermined time ahead is referred to as an evaluation section. The predetermined time may be appropriately determined according to the processing cycle of the control unit 12 and the time related to the optimization calculation, but the specific value is, for example, 1 minute. The control input calculation unit 122 discretizes the evaluation sections at predetermined intervals and calculates the amount of change in the shaft torque at each time point at each predetermined interval. The predetermined interval is the processing cycle of the control unit 12, for example, 1 millisecond.

Ｗ_１・Ｆｕｅｌ_ｃｏｎ（ｔ）は、自車Ｂの燃費に関する燃費項である。燃費項は、予測モデルにより予測される自車Ｂの速度と、軸トルクとを変数とする関数である。具体的には、燃費項は、評価区間を離散化した所定間隔（１ミリ秒）の間に噴射する燃料の量（燃料消費量）を、所定間隔の間の自車Ｂの移動距離ｒで除算した値である。移動距離ｒは、自車Ｂの速度ｖ（ｔ）に所定間隔を乗算して算出される。燃料消費量は、下記式（６）で表される。

Ｗ_ｅは、エンジン回転数である。ｎ_ｓｔは、エンジン４の１回転当たりの燃料噴射回数である。Ｑは、燃料噴射量である。Ｎ_ｅは、エンジン４のシリンダ数である。また、式（６）は、燃料消費量の単位を立方ミリメートルからリットルに変換するため、１０^－６を乗算している。 The integrand L is expressed by the following equation (5).

W1 ・ Fuel _con (t) is _a fuel consumption term relating to the fuel consumption of the own vehicle B. The fuel consumption term is a function in which the speed of the own vehicle B predicted by the prediction model and the shaft torque are variables. Specifically, in the fuel consumption term, the amount of fuel (fuel consumption) injected during a predetermined interval (1 millisecond) in which the evaluation section is discretized is calculated by the moving distance r of the own vehicle B during the predetermined interval. It is the divided value. The moving distance r is calculated by multiplying the speed v (t) of the own vehicle B by a predetermined interval. The fuel consumption is expressed by the following formula (6).

_We is the engine speed. _nst is the number of fuel injections per revolution of the engine 4. Q is the fuel injection amount. _Ne is the number of cylinders of the engine 4. Also, equation (6) is multiplied by ^10-6 to convert the unit of fuel consumption from cubic millimeters to liters.

W ₂ · (u (t)) ^2/2 is a torque term relating to the amount of change in shaft torque. W ₃ · (v (t) -vd) ^2/2 is a velocity deviation term relating to the deviation between the velocity and the target velocity. W ₄ · (P _distance · v (t) + C _distance −d) ^2/2 is a distance deviation term relating to the deviation between the inter-vehicle distance and the target inter-vehicle distance. P _distance · v (t) corresponds to the minimum inter-vehicle distance. The P _distance and the C _distance may be appropriately determined by experiments or the like according to the running performance of the own vehicle B. D is the inter-vehicle distance (state quantity). vd is the target speed.

The integrand L is the distance deviation between the fuel consumption term related to the fuel consumption of the own vehicle B, the torque term of the amount of change in the shaft torque predicted by the prediction model, and the deviation between the inter-vehicle distance predicted by the prediction model and the target inter-vehicle distance. Includes terms and. Then, the control input calculation unit 122 minimizes the evaluation function J obtained by integrating the integrand L including the fuel consumption term, the torque term, and the distance deviation term from the present time to a time point ahead of a predetermined time. Calculate the amount of change in torque.

The control input calculation unit 122 solves the optimization problem of the evaluation function J using the integrand L including the fuel consumption term, the torque term, and the distance deviation term, and thereby optimizes the own vehicle at each time point in the evaluation section. The state of B can be determined. Specifically, the control input calculation unit 122 calculates the optimized fuel consumption, the amount of change in shaft torque, and the inter-vehicle distance at each time point between the current time t and the time point t + T a predetermined time ahead (evaluation section). .. By doing so, the control input calculation unit 122 can optimize each term in the evaluation section while balancing the fuel consumption, the amount of change in the shaft torque, and the inter-vehicle distance, which are in a trade-off relationship.

Further, since the control input calculation unit 122 includes the change amount of the shaft torque as the control input in the evaluation function J, the control input calculation unit 122 can suppress a large change in the change amount of the shaft torque. Therefore, the control input calculation unit 122 can suppress a large change in the optimum solution when, for example, the preceding vehicle suddenly decelerates. As a result, the control input calculation unit 122 can prevent the evaluation function J from being unable to perform the optimization calculation.

The integrand L further includes a speed deviation term of the deviation between the speed of the own vehicle B and the target speed predicted by the prediction model. Since the control input calculation unit 122 includes a speed deviation term in the evaluation function instead of a term related to acceleration / deceleration, it is possible to suppress an increase in the evaluation function when the preceding vehicle decelerates significantly. As a result, the control input calculation unit 122 can prevent the optimization calculation from becoming impossible.

Each of W ₁ , W ₂ , W ₃ and W ₄ in equation (4) is a weight for each term. Specific values of W ₁ , W ₂ , W ₃ and W ₄ are, for example, 10 ^ -6, 1, 10, and 100. The control input calculation unit 122 weights the fuel consumption so that the influence of the fuel consumption term is large. Specifically, the control input calculation unit 122 minimizes the evaluation function J obtained by integrating the integrand L with the weight of the fuel consumption term larger than a predetermined value from the present time to a time point ahead of a predetermined time. The amount of change in the shaft torque to be changed is sequentially calculated. More specifically, the control input calculation unit 122 minimizes the evaluation function J obtained by integrating the integrand L obtained by changing the weight value of the fuel consumption term from 10 ^ -6 to 5 × 10 ^ -6. The amount of change in the shaft torque to be changed is sequentially calculated. By doing so, the control input calculation unit 122 can calculate the amount of change in the shaft torque that will improve future fuel efficiency.

The control input calculation unit 122 is not limited to the fuel consumption term, and the weight of any one of the torque term, the distance deviation term, and the speed deviation term may be heavily weighted. For example, the control input calculation unit 122 sets the weight of the speed deviation term of the deviation between the speed and the target speed to be larger than a predetermined value. Specifically, the control input calculation unit 122 minimizes the evaluation function J obtained by integrating the integrand L in which the weight value of the speed deviation term of the deviation between the speed and the target speed is changed from 10 to 15. The amount of change in the shaft torque to be changed is sequentially calculated. By doing so, the control input calculation unit 122 can calculate the amount of change in the shaft torque that reduces the change in the speed of the own vehicle B.

The control input calculation unit 122 calculates the amount of change in the shaft torque so that the inter-vehicle distance does not become smaller than the minimum inter-vehicle distance. For example, the control input calculation unit 122 sequentially calculates the amount of change in the shaft torque that minimizes the evaluation function J so that the inter-vehicle distance predicted by the prediction model does not become less than the minimum inter-vehicle distance smaller than the target inter-vehicle distance. .. For example, the minimum inter-vehicle distance is increased as the speed of the own vehicle B increases. Further, the minimum inter-vehicle distance is increased as the total weight of the own vehicle B is larger.

Specifically, the control input calculation unit 122 calculates the amount of change in the shaft torque that minimizes the evaluation function J with the following equation (7) as a constraint condition.
P _distance · v (t) ≤ D ... (7)
In other words, the control input calculation unit 122 minimizes the evaluation function J so that the inter-vehicle distance D is equal to or greater than the minimum inter-vehicle distance P _distance · v (t). In this way, the control input calculation unit 122 can prevent the inter-vehicle distance between the own vehicle B and the preceding vehicle from becoming too small by using the constraint condition regarding the inter-vehicle distance. Hereinafter, P _minute v (t) is referred to as Min. Further, Min, which is the minimum inter-vehicle distance, changes depending on the speed of the own vehicle, but in the following description, it is assumed that Min is constant.

FIG. 3 is a graph plotting the time change of the inter-vehicle distance D when the own vehicle B is controlled by using the constraint condition. The horizontal axis of FIG. 3 indicates the time t, and the vertical axis indicates the inter-vehicle distance D. The broken line indicates the minimum inter-vehicle distance Min. As shown in FIG. 3, when the own vehicle B is controlled using the constraint condition, the inter-vehicle distance D does not become less than the minimum inter-vehicle distance Min, and the vehicle control device 1 makes the inter-vehicle distance D too small. Can be suppressed.

FIG. 4 is a graph plotting the time change of the inter-vehicle distance D according to the comparative example in which the own vehicle B is controlled without using the constraint condition. The horizontal axis of FIG. 4 indicates the time t, and the vertical axis indicates the inter-vehicle distance D. The broken line indicates the minimum inter-vehicle distance Min. As shown in FIG. 4, if the own vehicle B is controlled without using the constraint condition, the inter-vehicle distance D may be less than the minimum inter-vehicle distance Min.

The target setting unit 123 sets a target value for controlling the own vehicle B. For example, the target setting unit 123 sets the target shaft torque at the next point in time at the present time. Specifically, the target setting unit 123 calculates the sum of the change amount of the shaft torque at the next time point in the change amount of the shaft torque at each time point calculated by the control input calculation unit 122 and the current shaft torque. , Set as the target shaft torque at the next time.

The target setting unit 123 may set a target acceleration for controlling the own vehicle B. For example, the target setting unit 123 sets the acceleration of the own vehicle B at the next time point predicted by the calculated change amount of the shaft torque to the target acceleration at the next time point at the present time.

The actuator control unit 124 controls various actuators mounted on the own vehicle B so as to have a target value set by the target setting unit 123. For example, the actuator control unit 124 controls an actuator for controlling acceleration / deceleration of the own vehicle B mounted on the own vehicle B so that the shaft torque becomes the target shaft torque. Specifically, the actuator control unit 124 controls the acceleration / deceleration of the own vehicle B by changing the amount of fuel injected into the fuel injection unit 31. More specifically, the actuator control unit 124 increases the acceleration a in the traveling direction of the own vehicle B by increasing the amount of fuel to be injected, and decreases the acceleration a by reducing the amount of fuel. Further, the actuator control unit 124 injects the fuel injection unit 31 with an amount of fuel whose shaft torque becomes the target shaft torque by using the control map M (see FIG. 2) stored in the storage unit 11. By doing so, the actuator control unit 124 can inject the fuel injection unit 31 with an amount of fuel that optimizes future fuel efficiency.

Further, the actuator control unit 124 controls the braking valve 32 so that the acceleration of the own vehicle B becomes the target acceleration. For example, the actuator control unit 124 controls the second actuator to open and close the braking valve 32 so that the difference between the current acceleration of the own vehicle B and the target acceleration set by the target setting unit 123 becomes small. Specifically, when the current acceleration is larger than the target acceleration, the actuator control unit 124 opens the braking valve 32 to operate the air brake 5 to decelerate the own vehicle B. In this way, the actuator control unit 124 controls the braking valve 32 in addition to the fuel injection unit 31, so that the vehicle B can be controlled with higher accuracy than when only the fuel injection unit 31 is controlled.

[Process executed by vehicle control device 1]
Hereinafter, the flow of processing executed by the vehicle control device 1 will be described with reference to FIG. FIG. 5 is a flowchart showing an example of the flow of processing executed by the vehicle control device 1. The flowchart of FIG. 5 is sequentially executed while the own vehicle B equipped with the vehicle control device 1 is traveling following the preceding vehicle.

First, the information acquisition unit 121 acquires the detection result detected by the sensor group 2 (step S1). Specifically, the information acquisition unit 121 acquires the axial torque and the inter-vehicle distance of the own vehicle B from the sensor group 2. Further, the information acquisition unit 121 acquires the speed and acceleration of the own vehicle B and the acceleration and speed of the preceding vehicle from the sensor group 2.

Subsequently, the control input calculation unit 122 calculates the amount of change in the shaft torque that minimizes the evaluation function J (step S2). The evaluation function J is obtained by integrating the integrand L including the fuel consumption term of the fuel consumption of the own vehicle B, the torque term of the change amount of the shaft torque, and the distance deviation term of the deviation between the inter-vehicle distance and the target inter-vehicle distance. Specifically, the control input calculation unit 122 minimizes the evaluation function J obtained by integrating the integrand L from the present time to a predetermined time ahead, at each time point from the present time to a predetermined time ahead. Calculate the amount of change in shaft torque.

The target setting unit 123 sets the target shaft torque according to the calculated change amount of the shaft torque (step S3). For example, the target setting unit 123 sets the sum of the change amount of the shaft torque at the next time point and the shaft torque at the present time to the target shaft torque at the next time point.

Next, the target setting unit 123 sets the acceleration at the next time point predicted by the calculation of the amount of change in the shaft torque to the target acceleration at the next time point (step S4). The process of step S4 may be executed before the process of step S3, or the process of step S3 and the process of step S4 may be executed in parallel.

The actuator control unit 124 controls the fuel injection unit 31 so that the target shaft torque is reached (step S5). Specifically, the actuator control unit 124 controls the fuel injection unit 31 so that the target shaft torque set by the target setting unit 123 is reached at the next time point after the current time. Further, the actuator control unit 124 controls the braking valve 32 so as to reach the target acceleration (step S6). The vehicle control device 1 may execute the process of step S5 and the process of step S6 in parallel.

[Effect of vehicle control device 1 according to the embodiment]
As described above, the vehicle control device 1 determines the amount of change in the shaft torque output by the output shaft of the engine 4 of the own vehicle B, thereby leading the future speed, shaft torque, and own vehicle B of the own vehicle B. It remembers a prediction model that predicts the distance to a car. Next, the vehicle control device 1 has a fuel consumption term of the fuel consumption of the own vehicle B whose variables are the speed and the shaft torque of the own vehicle B predicted by the prediction model, a torque term of the amount of change in the shaft torque, and an inter-vehicle distance. The evaluated function J is obtained by integrating the integrand L including the distance deviation term of the deviation from the target vehicle-to-vehicle distance from the present time to a time point in a predetermined time ahead. Then, the vehicle control device 1 sequentially calculates the amount of change in the shaft torque at each time point from the present time to the time point ahead of a predetermined time as a control input for minimizing the evaluation function J.

The vehicle control device 1 controls an actuator for controlling acceleration / deceleration of the own vehicle B according to the amount of change in the shaft torque that minimizes the evaluation function J obtained by integrating the integrand L including the term of fuel consumption. This controls the own vehicle B. By doing so, the vehicle control device 1 can control the own vehicle B so that the future fuel consumption is optimized. Further, the vehicle control device 1 can control the speed of the own vehicle B so that the fuel consumption of the own vehicle B, the change in the shaft torque, and the inter-vehicle distance D from the preceding vehicle are all optimized. Therefore, the vehicle control device 1 can control the own vehicle B while balancing the fuel consumption of the own vehicle B, the amount of change in the shaft torque, and the inter-vehicle distance D with the preceding vehicle, which are in a trade-off relationship.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes can be made within the scope of the gist. be. For example, all or part of the device can be functionally or physically distributed / integrated in any unit. Specifically, in the embodiment, the actuator control unit 124 controls the air brake 5 by controlling the braking valve 32, but is not limited to this, and controls an auxiliary brake such as a compression release brake or a retarder. May be good. Also included in the embodiments of the present invention are new embodiments resulting from any combination of the plurality of embodiments. The effect of the new embodiment produced by the combination has the effect of the original embodiment together.

1 Vehicle control device 11 Storage unit 12 Control unit 121 Information acquisition unit 122 Control input calculation unit 123 Target setting unit 124 Actuator control unit 2 Sensor group 31 Fuel injection unit 32 Braking valve 4 Engine 5 Air brake

Claims (5)

By determining the amount of change in the shaft torque output by the output shaft of the engine of the own vehicle, a prediction model that predicts at least the future speed of the own vehicle, the shaft torque, and the distance between the own vehicle and the preceding vehicle can be obtained. A storage unit to memorize and
The fuel consumption term of the fuel consumption of the own vehicle whose variables are the speed of the own vehicle and the shaft torque predicted by the prediction model, the torque term of the amount of change in the shaft torque predicted by the prediction model, and the said. As a control input that minimizes the evaluation function obtained by integrating the integrand including the distance deviation term of the deviation between the inter-vehicle distance and the target inter-vehicle distance predicted by the prediction model from the present time to the time point in a predetermined time ahead. , A control input calculation unit that sequentially calculates the amount of change in the shaft torque at each time point from the present time to a time point ahead of a predetermined time.
The sum of the change amount of the shaft torque at the next time point of the present time and the shaft torque at the present time among the change amounts of the shaft torque at each time point calculated by the control input calculation unit is the next time point. The target setting unit to be set as the target shaft torque of
An actuator control unit that controls an actuator for controlling acceleration / deceleration of the own vehicle mounted on the own vehicle so that the shaft torque becomes the target shaft torque.
A vehicle control device. The control input calculation unit sequentially changes the amount of change in the shaft torque that minimizes the evaluation function so that the inter-vehicle distance predicted by the prediction model does not become less than the minimum inter-vehicle distance smaller than the target inter-vehicle distance. calculate,
The vehicle control device according to claim 1. The control input calculation unit minimizes the evaluation function obtained by integrating the integrand with the weight of the fuel consumption term larger than a predetermined value from the present time to a time point ahead of a predetermined time. Sequentially calculate the amount of change in shaft torque,
The vehicle control device according to claim 1 or 2. The control input calculation unit includes the integrand that further includes the fuel consumption term, the torque term, the distance deviation term, and the speed deviation term of the deviation between the speed of the own vehicle and the target speed. The amount of change in the shaft torque that minimizes the evaluation function obtained by integrating from the current time to a predetermined time ahead is sequentially calculated.
The vehicle control device according to any one of claims 1 to 3. The target setting unit sets the acceleration of the own vehicle at the next time point predicted by the calculated change amount of the shaft torque as the target acceleration.
The actuator control unit controls the first actuator so that the shaft torque becomes the target shaft torque, and controls the second actuator so that the acceleration of the own vehicle becomes the target acceleration.
The vehicle control device according to any one of claims 1 to 4.

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