JP4742925B2 - Vehicle motion control device - Google Patents

Description

  The present invention relates to a motion control device that controls the motion of a vehicle based on an operation amount of an operation member operated by a driver.

Patent Document 1 discloses an output torque control device for an internal combustion engine that controls the output torque of the internal combustion engine so that the amount of change in the longitudinal acceleration of the vehicle is greater when the accelerator pedal depression speed is large than when it is small. Are listed.
JP-A-2005-155212

However, the appropriate value for assigning the target jerk to the accelerator operation speed not only changes depending on the individual driving skill and preference, but also changes depending on the driving intention at that time even for the same individual.
For this reason, even if the average control can be satisfied with the conventional control, the output torque of the internal combustion engine cannot be controlled with the optimum characteristics corresponding to the individual characteristics of the driver or the difference in the driving environment, The characteristics that are easy to use for the driver could not be obtained.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vehicle motion control device that can control the accelerator operation speed to a jerk suitable for the driver's intention.

Therefore, the vehicle motion control apparatus according to the present invention includes a means for detecting an operation amount of an operation member operated by a driver to control the motion of the vehicle, a means for calculating a change speed of the operation amount, a target jump When the degree is Jtg and the change amount of the manipulated variable is dAPO,
[Equation 8]
Jtg = A × (dAPO) ^H
(A, H is the coefficient, but H> 1.0) means for calculating a target jerk corresponding to the rate of change of said operating amount based on the correlation represented by the relationship, is configured to include a, uphill road in Even if there is, the output of the drive source is controlled so that the actual degree of achievement of the vehicle becomes the target degree of achievement.

According to the above configuration, the target jerk Jtg is calculated based on the correlation expressed by the relationship of the change amount dAPO of the operation amount (for example, accelerator operation amount) by the driver and the relationship expressed by the following equation (8). Since the calculation is performed, it becomes possible to realize an acceleration feeling corresponding to the change rate of the operation amount by the driver .

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a system diagram of a vehicle internal combustion engine to which a vehicle motion control apparatus according to the present invention is applied.
An internal combustion engine 1 shown in FIG. 1 is mounted on an automobile (not shown), and engine generated torque taken out from a crankshaft of the internal combustion engine 1 is transmitted to drive wheels via a transmission.

The internal combustion engine 1 is a multi-cylinder four-cycle gasoline engine. In each cylinder, air that has passed through an air cleaner 2 is sucked through an intake duct 3, an intake collector 4, an intake manifold 5, and an intake valve 6. The
The intake air amount of the internal combustion engine 1 is adjusted by an electric control throttle 7 interposed in the intake duct 3.

The electric throttle 7 is a mechanism for opening and closing a butterfly throttle valve 7a with a throttle motor (throttle actuator) 7b.
A fuel injection valve 9 is provided in each intake port portion of each cylinder, and fuel (gasoline) is injected into the intake port of each cylinder.
However, the fuel injection valve 9 may be an in-cylinder direct injection internal combustion engine in which fuel is directly injected into the combustion chamber 10.

The fuel injected from the fuel injection valve 9 is ignited and burned by spark ignition by the spark plug 15 in the combustion chamber 10.
Each ignition plug 15 is directly attached with an ignition coil 16 having a built-in power transistor, and the ignition timing and ignition energy of the ignition plug 15 are adjusted by controlling energization to the ignition coil 16. .

The combustion exhaust in the combustion chamber 10 is discharged to the atmosphere via an exhaust valve 11, an exhaust manifold 12, and an exhaust duct 13.
The exhaust duct 13 is provided with a catalytic converter 14 for purifying harmful components in the exhaust.
The power transistor for controlling energization to the throttle motor 8, the fuel injection valve 9, and the ignition coil 16 is controlled by an engine control unit (ECU) 21 incorporating a microcomputer.

Detection signals from various sensors are input to the engine control unit 21.
The various sensors include an air flow meter 22 that detects the intake air flow rate Qa (mass flow rate) of the internal combustion engine 1 on the upstream side of the electric throttle 7, and an oxygen concentration in the exhaust gas on the upstream side of the catalytic converter 14. An air-fuel ratio sensor 23 for detecting the air-fuel ratio, a rotational speed sensor 24 for detecting the rotational speed Ne (rpm) of the internal combustion engine 1, and an accelerator opening for detecting the depression amount (accelerator opening) APO of the accelerator pedal 25 operated by the driver. A degree sensor 26, a throttle sensor 27 for detecting the opening TVO (deg) of the throttle valve 7a, a vehicle speed sensor 28 for detecting a traveling speed (vehicle speed) VSP (km / h) of a vehicle on which the internal combustion engine 1 is mounted, and the like. Is provided.

Note that the accelerator operation is not limited to a depression of the accelerator pedal 25, and may be a lever operation, a grip operation, or the like.
The engine control unit 21 controls the fuel injection amount by the fuel injection valve 9 as follows.
First, from the intake air flow rate Qa detected by the air flow meter 22 and the engine rotational speed Ne detected by the rotational speed sensor 24, a basic for forming a mixture of the target air-fuel ratio at the cylinder intake air amount at that time. A fuel injection amount Tp is calculated.

Further, various correction coefficients CO are calculated based on the coolant temperature of the internal combustion engine 1 and the air-fuel ratio feedback correction coefficient ALPHA is calculated so that the air-fuel ratio detected by the air-fuel ratio sensor 23 approaches the target air-fuel ratio. The final fuel injection amount Ti is set by correcting the basic fuel injection amount Tp with the correction coefficients CO and ALPHA.
Then, an injection pulse signal having a pulse width corresponding to the final fuel injection amount Ti is output to each fuel injection valve 9 in accordance with the stroke of each cylinder.

The pressure of the fuel supplied to the fuel injection valve 9 is adjusted so that the fuel injection valve 9 injects an amount of fuel proportional to the valve opening time, and the pulse of the injection pulse signal An amount of fuel proportional to the width, that is, the valve opening time of the fuel injection valve 9 is injected.
The engine control unit 21 calculates an ignition timing (ignition advance value) from the basic fuel injection amount Tp (engine load) and the engine rotational speed Ne, and the ignition control is based on the ignition timing and a predetermined energization time. The on / off control of the power transistor built in the coil 16 is controlled.

Further, the engine control unit 21 controls the intake air amount (output torque) of the internal combustion engine 1 by controlling the opening degree of the electric throttle 7 as follows.
The flowchart of FIG. 2 shows the main routine of the throttle opening control.
First, in step S1, a vehicle target acceleration (second target acceleration Atg2 described later) is calculated from the accelerator opening APO.

In step S2, a target tire torque for obtaining the target acceleration (second target acceleration Atg2) calculated in step S1 is calculated from the vehicle weight and running resistance (gradient resistance, air / rolling resistance, etc.).
In step S3, the target engine torque for obtaining the target tire torque is calculated from the target tire torque, the reduction ratio, the friction of the drive shaft / engine, the moment of inertia of the drive shaft / engine, the auxiliary machine load, and the like.

In step S4, a target average effective pressure (IMEP) for obtaining the target engine torque is calculated.
In step S5, a target intake pressure for obtaining an intake air amount necessary to obtain the target average effective pressure is calculated.
The step S4 can be omitted, and the target intake pressure can be obtained directly from the target engine torque.

In step S6, a target throttle passage intake flow rate for obtaining the target intake pressure is calculated.
In step S7, a target throttle opening area for obtaining the target throttle passage intake flow rate is calculated from the target intake pressure or the detected value of the intake pressure, the atmospheric pressure, and the like.
In step S8, the target throttle opening corresponding to the target throttle opening area is calculated from the correlation between the throttle opening area and the throttle opening stored in advance.

In step S9, the throttle motor (throttle actuator) 7b is feedback-controlled so that the opening degree of the throttle valve 7a detected by the throttle sensor 27 approaches the target throttle opening degree (control means, acceleration control means).
By controlling the throttle valve opening in step S9, the target acceleration (second target acceleration Atg2) set in step S1 is realized.

Here, the calculation of the target acceleration in step S1 will be described in detail according to the flowchart of FIG.
In step S11, the accelerator opening APO (deg) detected by the accelerator opening sensor 26 is input.
Here, the accelerator pedal 25 corresponds to an operation member that the driver operates to control the movement of the vehicle, the accelerator opening APO corresponds to the operation amount of the operation member, and the accelerator opening sensor 26 operates. It corresponds to a quantity detection means.

In the next step S12, a first target acceleration Atg1 (m / s ² ) is calculated based on the accelerator opening APO (first target acceleration calculating means).
As shown in FIG. 4, the first target acceleration Atg1 is obtained from the correlation between the accelerator opening APO (accelerator operation amount) stored in advance and the acceleration.
The first target acceleration Atg1 can be calculated from the characteristics of the accelerator opening APO and the torque, and the first target acceleration Atg1 is calculated from the accelerator opening APO and the engine rotational speed or the vehicle speed. You can also.

In step S13, the first target jerk Jtg1 is calculated from the difference between the current value of the first target acceleration Atg1 and the previous value (time differential value of the first target acceleration Atg1).
In step S14, the accelerator operation speed dAPO (deg / s) is calculated from the difference between the current value and the previous value of the accelerator opening APO (time differential value of the accelerator opening APO) (operation speed calculating means).

In step S 15, in order to calculate the target jerk J tg (m / s 3) from the accelerator operation speed d A P O, the correlation between the accelerator operation speed d A P O and the target jerk J tg is determined. The coefficient n to be determined is determined based on the button operation of the driver (passenger) (correlation varying means).
In the present embodiment, the correlation between the accelerator operating speed d A P O and the target jerk J tg is represented by function number as shown in Equation 1.

  In the above equation 1, H, C, and dACC are coefficients. When these reference values are H0, C0, and dACC0, the coefficients H, C, and dACC are expressed by equation 2 using the coefficients S and n. It is expressed as follows.

Here, among the coefficients S and n for determining the coefficients H, C, and dACC, the coefficient S is given as a fixed value so that the driver can select the coefficient n, and the coefficient n selected by the driver is The coefficients H, C, and dACC are used to determine, and then, a function for determining the target jerk Jtg is determined from the accelerator operation speed dAPO.
Finally, based on the correlation reflecting the driver's intention, the target jerk Jtg corresponding to the accelerator operation speed dAPO at that time is obtained.

The coefficient n can be used in common for all the coefficients H, C, and dACC to calculate the coefficients H, C, and dACC, and the coefficients n used for calculating the coefficients H, C, and dACC are individually selected. The coefficient n may be changed and changed only for some of the coefficients H, C, and dACC.
For example, as shown in FIG. 5, the coefficient n is selected by providing a steering button 101 with a plus button 102 and a minus button 103, and a change instruction signal (up instruction signal, down instruction signal based on the operation of these buttons 102, 103. ) Is read by the engine control unit (ECU) 21.

Specifically, every time the driver operates the plus button 102, the coefficient n is set to increase by 1, and every time the driver operates the minus button 103, the coefficient n is set to decrease by 1.
In selecting the coefficient n based on the operation of the buttons 102 and 103, the coefficient n can be variably set between a predetermined maximum value and minimum value.

Then, the engine control unit (ECU) 21 updates the coefficient n based on the previous input of the coefficient n and a new change instruction signal (up instruction signal, down instruction signal).
The coefficient n is selected every time one button or switch is operated (every time a change instruction signal is input), for example, 0 → 1 → 2 → 1 → 0 → 1... 0 → 1 → 2 → As in 0 → 1 → 2 → 0..., The coefficient n can be sequentially changed in a loop within a preset variable range.

Further, it is possible to generate a change instruction signal that continuously changes depending on the volume or dial, and to change the coefficient n steplessly based on the change instruction signal.
Also, a plurality of modes such as a comfort mode, a general mode, and an expert mode are set, a coefficient n is stored in advance for each mode, and the coefficient n corresponding to the mode selected by the driver with the mode selection switch is selected. (See FIG. 6).

Furthermore, the coefficient n can be automatically selected based on information such as individual characteristics of the driver and the driving environment of the vehicle, and a signal specifying the coefficient n from the outside. The selection of the driver can also be restricted based on the characteristics of the individual driver and the driving environment of the vehicle.
The individual characteristics of the driver may include age / gender, license history / driving qualification, and also the tendency of gear shift / accelerator operating speed in the past driving. , Speed limit, congestion, road surface gradient, weather (temperature, rainfall, snow cover), and the number of passengers and time zone.

Further, the coefficient n, or it may be allowed to change the coefficient S in place of the coefficient n, instead of changing the coefficient S and / or coefficients n, may also be changed S ^n, direct Factor H, C , DACC can be changed.
However, the equation for obtaining the target jerk Jtg from the accelerator operation speed dAPO is not limited to the above equation 1, and a plurality of maps storing the correlation between the accelerator operation speed dAPO and the target jerk Jtg are stored. It can be set as the structure which selects the map used for the calculation of jerk Jtg.

In step S16, the target jerk Jtg (m / s ³ ) is calculated from the accelerator operation speed dAPO at that time according to the function of Equation 1 determined based on the coefficient n (and / or coefficient S) calculated in step S15. Calculate.
Thus, for the accelerator operating speed dAPO, will be the target jerk Jtg (m / s ³⁾ is uniquely determined based on the number 1 of the function, to the target jerk Jtg (m / s ³⁾ By controlling the acceleration of the vehicle based on this, the acceleration feeling can be stabilized regardless of the driving conditions, and the operation characteristics can be easily handled by the driver.

Further, since the correlation between the accelerator operation speed dAPO and the target jerk Jtg (m / s ³ ) can be changed, the driver can change the correlation arbitrarily based on the driver's change instruction. The target jerk Jtg (m / s ³ ) can be set with the optimal characteristics for the intention, and the driver's intention can be reflected when the correlation is automatically changed. For example, the target jerk can be forcibly suppressed in consideration of vehicle safety.

Also, human acceleration feeling to exhibit nonlinear characteristics has been confirmed by the present inventor with respect to jerk of the vehicle, the coefficient H for example H> 1 for determining the number of function in this embodiment. 0 If the target jerk J tg is given as a non-linear characteristic to the accelerator operation speed d A P O, an acceleration feeling corresponding to the accelerator operation speed d A P O can be realized.
Furthermore, when the correlation between the accelerator operation speed d A P O and the target jerk J tg (m / s 3) is changed by changing the coefficient n shown in Equation 1, the sensitivity is such that humans feel a difference. S is set, and this sensitivity (coefficient) S is raised to the nth power and multiplied by the reference value of the coefficients H 1, C 2, d A CC, so that the coefficient n is 0 → 1 → 2 (or 0 → −1 → 2 ), The correlation between the accelerator operation speed d A P O and the target jerk J tg can be switched at an appropriate step for human feeling.

Accordingly, the driver (passenger) can easily obtain the desired acceleration feeling by appropriately changing the coefficient n even during traveling.
In step S17, the final target of the motion control is based on the first target jerk Jtg1, the target jerk Jtg, the first target acceleration Atg1, and the previous value Atg2 _z of the second target acceleration Atg2 described later. A second target acceleration Atg2 as a target value is calculated (second target acceleration calculating means).

In step S1, the second target acceleration Atg2 is calculated and output as described above, and in steps S2 to S9, the target throttle opening degree at which the second target acceleration Atg2 is obtained is finally determined. And the opening degree (intake air amount) of the throttle valve 7a is controlled.
Here, the second target acceleration based on the previous value Atg2 _z of the first target jerk Jtg1, the target jerk Jtg, the first target acceleration Atg1, and the second target acceleration Atg2 in the step S17. The calculation process of Atg2 will be described in more detail according to the flowchart of FIG.

  In step S101, an extension time Δt is calculated from the first target jerk Jtg1 and the target jerk Jtg.

The first target jerk Jtg1 is a value corresponding to the correlation between the accelerator opening APO and the first target acceleration Atg1, but the target jerk Jtg is a value set individually based on the accelerator operation speed dAPO. And Jtg1 = Jtg is not always true.
Assuming that Jtg1 ≧ Jtg, as shown in FIG. 8, it is the same when the target acceleration is changed according to the target jerk Jtg as compared with the case where the target acceleration is changed according to the first target jerk Jtg1. An extra transient operation time Δt is required to reach the acceleration, and this is calculated as an extended time of the transient operation in the present application.

  In the next step S102, the cumulative extension time ΔT is calculated by integrating the extension time Δt.

In Equation 4, dt represents the sampling period (calculation period), Delta] t _z represents the previous value of the extension time Delta] t, by subtracting the sampling period dt from the integral value of the extension time Delta] t, the elapsed time period is subtracted each time It is made to do.
When controlling the acceleration of the vehicle, a limit may be added so that Δt ≧ 0 or Jtg1 ≧ Jtg, and ΔT may not be equal to or less than a predetermined value (0 or dt).

Further, when the deceleration of the vehicle is controlled by brake control, a restriction may be applied so that Jtg1 ≦ Jtg.
In step S103, it calculates the first difference between the target acceleration Atg1 and the previous value Atg2 _z of the second target acceleration Atg2 (acceleration deviation) ΔAtg.

  In step S104, the acceleration deviation ΔAtg is divided by the cumulative extension time ΔT to calculate a third target jerk Jtg2.

The cumulative extension time ΔT is a time required to catch up with the first target acceleration Atg1 with the target jerk Jtg. As a result, the target jerk Jtg≈the third target jerk Jtg2 is obtained. If the second target acceleration Atg2 is changed according to the target jerk Jtg2, the second target acceleration Atg2 is changed to follow the first target acceleration Atg1 with the target jerk Jtg.
Accordingly, in step S105, the second target acceleration Atg2 is calculated by integrating the third target jerk Jtg2.

As described above, in the present embodiment, the first target acceleration Atg1 is calculated from the accelerator operation amount APO, while the first target jerk Jtg1 is calculated as a time differential value of the first target acceleration Atg1.
Further, independently of the correlation between the accelerator operation amount APO and the first target acceleration Atg1, the correlation between the accelerator operation speed dAPO and the target jerk Jtg is variably set according to the driver's intention, and the accelerator operation speed dAPO is set. To calculate the target jerk Jtg.

Then, the second target acceleration Atg2 that changes following the first target acceleration Atg1 with the target jerk Jtg is calculated, and the internal combustion engine that generates the driving force of the vehicle so that the second target acceleration Atg2 is realized. Control the throttle opening of the engine.
In this embodiment, the throttle opening of the internal combustion engine is controlled to realize the second target acceleration Atg2. However, the means for realizing the second target acceleration Atg2 is controlled by the throttle opening control (intake amount). In the case of a diesel engine, the second target acceleration Atg2 can be realized by controlling the fuel amount, and various known means can be used as means for controlling the torque generated by the internal combustion engine. Applicable.

Further, the control target is not limited to the internal combustion engine, and can also be applied to control the lateral acceleration with respect to the steering operation and the deceleration with respect to the brake operation.
That is, it exerts a dynamic action / reaction, and can be controlled by, for example, a motor, a generator, a brake or a clutch using frictional force, and a gasoline engine or a diesel as a motor. A combination of an engine and various transmissions, a hybrid vehicle, or an electric vehicle or a fuel cell vehicle equipped with only a motor may be used.

In addition, the vehicle may be a vehicle on which a human boarding, such as a four-wheeled vehicle or a two-wheeled vehicle, and further, the motion control device of the present application can be applied to lateral or angular motion system acceleration control in the vehicle, Even in an aircraft, the motion control device of the present application can be applied regardless of the direction of acceleration (jumping) vector or moment.
Further, a control mode selection switch for canceling the control based on the second target acceleration Atg2 corresponding to the target jerk Jtg and controlling the movement of the vehicle based on the first target acceleration Atg1 corresponding to the accelerator operation amount APO. It can be provided.

The system figure of the internal combustion engine for vehicles in an embodiment. The flowchart which shows the main routine of the throttle control in embodiment. The flowchart which shows the calculation process of the target acceleration in embodiment. The diagram which shows the characteristic of the target acceleration with respect to the accelerator operating quantity in embodiment. The figure which shows the switch provided in the steering in embodiment. The diagram which shows the characteristic of the target jerk with respect to the accelerator operation speed in embodiment for every mode. The flowchart which shows the calculation process of the 2nd target acceleration based on the target jerk in embodiment. The time chart for demonstrating extension time (DELTA) t in embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Air cleaner, 3 ... Intake duct, 4 ... Intake collector, 5 ... Intake manifold, 6 ... Intake valve, 7 ... Throttle valve, 8 ... Throttle motor, 9 ... Fuel injection valve, 10 ... Combustion chamber, DESCRIPTION OF SYMBOLS 11 ... Exhaust valve, 12 ... Exhaust manifold, 13 ... Exhaust duct, 14 ... Catalytic converter, 21 ... Engine control unit, 22 ... Air flow meter, 23 ... Air-fuel ratio sensor, 24 ... Rotation speed sensor, 25 ... Accelerator pedal, 26 ... Accelerator opening sensor, 27 ... throttle sensor, 28 ... vehicle speed sensor

Claims (12)

An operation amount detection means for detecting an operation amount of an operation member operated by the driver to control the movement of the vehicle;
An operation speed calculating means for calculating a change speed of the operation amount;
When the target jerk is Jtg and the change rate of the manipulated variable is dAPO,
[Equation 8]
Jtg = A × (dAPO) ^H
A target jerk calculating means for calculating a target jerk corresponding to the change speed of the manipulated variable based on the correlation represented by the relationship (A, H are coefficients, where H>1.0);
The vehicle motion control apparatus is characterized in that the output of the drive source is controlled so that the actual climbing degree of the vehicle becomes the target jumping degree even on an uphill road . Correlation variable means for variably setting the correlation between the change rate of the manipulated variable and the target jerk,
The target jerk calculation means is:
2. The vehicle motion control apparatus according to claim 1, wherein a target jerk corresponding to a change speed of the operation amount is calculated based on the correlation variably set by the correlation varying means.   The vehicle according to claim 2, wherein the correlation variable unit variably sets the correlation between the change rate of the manipulated variable and the target jerk by changing a coefficient of a function related to the target jerk. Motion control device.   The correlation changing means sets the correlation between the change speed of the manipulated variable and the target jerk variably according to the intention of the passenger of the vehicle. Vehicle motion control device.   5. The vehicle motion control device according to claim 4, wherein the correlation varying means variably sets the correlation between the change rate of the manipulated variable and the target jerk based on a change instruction signal from a vehicle occupant. . The correlation variably set by the correlation variable means uses the coefficients H, C, and dACC when the change rate of the manipulated variable is dAPO and the target jerk is Jtg,
[Equation 1]
Jtg = C × {(dAPO × dACC) / C} ^H
2. The vehicle motion control according to claim 1, wherein the correlation variable means sets the correlation to be variable by changing at least one of the coefficients H, C, and dACC. apparatus. When the reference values of the coefficients H, C, and dACC are H0, C0, and dACC0, the coefficients H, C, and dACC are calculated using the coefficients S and n.
[Equation 2]
H = H0 × S ⁿ
C = C0 × S ⁿ
dACC = dACC0 × S ⁿ
Expressed as the correlation variable means, the coefficient S and / or factor n, or by varying the S ^n, motion of the vehicle according to claim 6, wherein the setting the correlation variable Control device. Wherein the correlation adjustment means, the coefficient S and / or factor n, or, S ^n, and the vehicle motion control according to claim 7, wherein the variably set on the basis of the change instruction signal by the rider of the vehicle apparatus. The correlation variable means sets the coefficient S and / or the coefficient n or S ⁿ to be variable independently for each of the coefficients H, C, and dACC based on a change instruction signal from a vehicle occupant. The vehicle motion control apparatus according to claim 8.   10. The vehicle motion control apparatus according to claim 8, wherein the change instruction signal is divided into a signal for instructing an increase in the coefficient n and a signal for instructing a down.   The vehicle motion control device according to claim 8 or 9, wherein the correlation varying means switches the coefficient n in a loop in order every time the change instruction signal is input.   The vehicle motion control apparatus according to any one of claims 1 to 11, further comprising control means for controlling the motion of the vehicle based on the target jerk.

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