JP3151110U - Drive control system for achieving target drive shaft power in automobiles - Google Patents

Abstract

An automobile control system capable of managing an engine with a large degree of freedom is provided. An internal combustion engine E includes control devices ECU, GSCU, SCU and sensors S1, S2. The control device controls the engine to supply a driving torque that changes according to the position α of the accelerator pedal AP. First, the accelerator pedal position α and the engine rotation speed or the vehicle forward speed v are acquired from the sensor means S1, S2. Next, the power PT to be applied to the drive wheels is determined based on the measured accelerator pedal position α and the calculated or acquired vehicle forward speed v. Then, based on the value determined as the power PT to be applied to the driving wheel and the forward speed v of the automobile, the driving torque CMREF to be supplied by the engine E is calculated correspondingly, and this driving torque CMREF is supplied. The engine E is controlled. [Selection] Figure 2

Description

  The present invention relates to an automobile drive control system. More particularly, the present invention relates to a drive control system of the type described in the preamble of claim 1.

  PCT International Publication No. 9737868 discloses such a system. That is, the corresponding desired traction force is determined from the stored graph using the accelerator position and the vehicle speed. Multiply the tractive force by the vehicle speed to determine the corresponding required power. At the same time, if the transmission ratio is not the maximum ratio then it is shifted to the maximum ratio. The maximum ratio is determined as a function of accelerator position and vehicle speed. The torque to be delivered by the engine is then calculated based on the required power and maximum transmission ratio.

European Patent Application Publication (EP-A-0559342) discloses a system for improving the fuel consumption of a vehicle equipped with an automatic transmission having a lock-up clutch. This system controls both the engine and the automatic transmission based on a target torque corresponding to the accelerator pedal stroke.
U.S. Pat. No. 353272 discloses a system for controlling a vehicle engine-transmission assembly. In this system, the power setpoint of the engine is determined by the position of the accelerator.

  An object of the present invention is to provide an innovative vehicle drive control system that can manage an engine with a greater degree of freedom than conventional systems. According to the present invention, this and other objects are achieved by a system having the main features as defined in the appended claim 1.

Means for solving the problems and effects of the device

  The control system according to the present invention is particularly an automobile having a servo assist gearbox having an input shaft that can be coupled to an engine shaft by a servo control clutch, wherein the first and second electrically driven actuator means are gearboxes. In addition, the present invention can be effectively applied to integrated drive control in the automobile associated with the clutch.

  In motor vehicles with servo-assisted or “automatic” gearboxes, drive control, ie control of power or torque applied to the drive wheels and transmitted to the ground, is provided by the driver from the accelerator pedal. Result of the combination of the command and the gear ratio selected by the driver.

  In these vehicles, unless the driver is particularly skilled, the drive control, ie the control of the torque that is actually applied to the drive wheels and transmitted to the ground, is generally not optimal.

  A further object of the present invention is that it is superior to the conventional method of individually controlling the engine and the gearbox, and allows improved and more direct control of the power applied to the drive wheels. It is an object of the present invention to provide an integrated drive control system that can make the engine more comfortable and can optimize engine use according to a predetermined purpose such as fuel consumption and / or reduction of exhaust gas emission.

  According to the present invention, this and other objects are achieved by an integrated drive control system having the main features defined in the appended claim 3.

  As will become clear in the following part of this specification, this type of system according to the present invention is not a driving torque supplied from a power unit, but a power applied to driving wheels of an automobile by an accelerator pedal. Based on the concept of direct control. In other words, the object to be controlled by the driver means, that is, the accelerator pedal, is not a purely simple engine, but the dynamic behavior of the automobile moving forward.

The block diagram of the control system which concerns on this invention. The block diagram which shows the example of an architecture of the integrated engine control system and servo assistance gearbox which concern on this invention. The graph which shows the relationship between the position of the accelerator pedal, the forward speed of a motor vehicle, and the power applied to a driving wheel in the system which concerns on this invention. FIG. 4 is a curve diagram representing the supplied torque as a function of rotational speed for various accelerator pedal positions for a particular internal combustion engine. FIG. 5 is a diagram of a curve representing the power applied to the drive wheels as a function of automobile forward speed for various accelerator pedal positions in a particular engine / transmission unit. 6 is a graph related to a method of changing a transmission ratio in the system according to the present invention. The flowchart which shows the method by which the system which concerns on this invention operate | moves. FIG. 3 is a diagram representing a target jerk in the direction of travel as a function of the power applied to the wheels, as used in the system according to the invention. The schematic diagram of the transmission between the engine shaft and drive wheel in the motor vehicle provided with the gear box. 3 is a graph of a curve representing the rotational speed and torque during gear changes in the system according to the present invention as a function of time on the horizontal axis. The figure which shows another example of the system architecture shown in FIG.

  In FIG. 1, an internal combustion engine of an automobile is denoted by E and its axis is denoted by M.

  A known type of electronic control unit ECU is associated with the engine E. Various sensor devices are connected to the control unit ECU. In particular, a sensor S1 associated with the accelerator pedal AP of the automobile is connected to the unit ECU. This sensor supplies a signal to the unit ECU, for example, a signal indicating the degree of pedal operation α expressed as a percentage varying between 0% (pedal release) and 100% (maximum pedal depression).

Another sensor S2 supplies a signal indicating the rotational speed ω _M of the shaft M of the engine E, expressed as the rotational speed n of the shaft per unit time, to the unit ECU.

Control unit ECU, the torque C _M supplied to the shaft M by the engine E, and is configured to implement procedures to control according to the position α of the accelerator pedal AP detected by the sensor S1.

For this purpose, an electronic memory M1 is attached to the unit ECU, and data for defining the power _PT to be applied to the driving wheels of the vehicle according to the position α of the accelerator pedal AP and the forward speed v of the vehicle is provided. I remember it. The data stored in the memory M1 defines a “drive capability map”. As will be described in detail below, this map, unlike the conventional engine management system, uniquely associates a predetermined power _PT to be applied to the drive wheels with the accelerator position α and the vehicle forward speed v. Is.

In other words, in the engine management system manufactured to date, the command given from the accelerator pedal means that the pedal position is supplied to specific variables or parameters of the engine, in particular, the rotational speed n per unit time and the driving torque supplied to the shaft. It was interpreted based on a “driving capability map” that directly corresponds to C _M. In the system according to the invention, the position α of the accelerator pedal AP is determined in a different way, ie the position α is a variable or parameter relating to the engine dynamics, in particular the forward speed v and the power P applied to the drive wheels. _This is interpreted based on a “driving capability map” corresponding to _{T 1} .

The driving capability map stored in the memory M1 is basically a discrete numerical expression of a predetermined curve for the engine E as illustrated in FIG. These curves determined in advance, for example by the method described below, make the accelerator pedal position α correspond to the power _PT to be applied to the drive wheels for each value of the forward speed v of the vehicle.

The control unit ECU is configured to repeatedly execute the following operations.
Obtain signals supplied from the sensors S1, S2 indicating the position α of the accelerator pedal AP and the rotational speed n of the engine E per unit time.
-Calculate the forward speed v of the car.
-The value of the power _PT to be applied to the wheel is determined by referring to the driving ability map stored in the memory M1 based on the acquired value of the accelerator pedal position α and the calculated value of the forward speed v of the vehicle. This determination of the value _PT generally involves interpolation between discrete numerical values stored in memory.
_{-Calculate the} drive torque C _MREF to be supplied from the engine E based on the power value _PT determined in the above steps.
Control the engine E so that a drive torque equal to the calculated torque C _MREF is supplied to the shaft M (eg fuel injection prior to ignition).

  As another method different from the above, the sensor S2 may detect the forward speed and supply data relating to this speed directly to the unit ECU. In that case, the speed need not be determined by calculation.

  Further features of the control system shown in FIG. 1 will become apparent from the following description of an integrated drive control system in an automobile with a servo-assisted gearbox.

  In FIG. 2, the internal combustion engine of the automobile is indicated by E. The engine shaft indicated by the symbol M can be coupled to the input shaft of the gear box G, that is, the primary shaft P by the friction clutch F. The gear box G includes an output shaft S that is coupled to a driving wheel (not shown) of the automobile by a known method.

  This gear box G is servo-assisted. The actuators A and B associated with the friction clutch F and the gear box G are, for example, electro-hydraulic, and are separated / coupled and coupled to the gear of the clutch F under the control of the gear shift control unit GSCU. / Separation can be performed respectively.

  A known type of electronic control unit ECU is associated with the engine E. This unit can control the engine E so that the engine supplies a driving torque that varies according to a predetermined measured quantity or parameter via the shaft M.

  In the drive control system shown in FIG. 2, the control unit ECU and the gear shift control unit GSCU of the engine E are sequentially controlled by the system control unit SCU. Various sensor devices are connected to the system control unit. In particular, a sensor S1 associated with the accelerator pedal AP of the automobile is connected to the unit SCU. This sensor supplies a signal to the unit SCU, for example, a signal indicating the degree of pedal operation α expressed as a percentage varying between 0% (pedal release) and 100% (maximum pedal depression).

To another sensor S2 unit SCU, and supplies a signal indicative of the rotational speed omega _M of the shaft M of the engine E which is expressed as the rotation speed n of the shaft per unit time.

  Here, as another example, the sensor S2 may detect the forward speed of the automobile.

  A further sensor represented by the symbol Sn is connected to the system control unit SCU for supplying a signal indicative of the gear ratio realized by the gearbox G, ie the transmission ratio.

  The system control unit SCU is configured to perform an automatic drive control procedure, in particular based on the position of the accelerator pedal AP detected by the sensor S1.

For this purpose, the unit SCU has a first electronic memory for storing data for defining the power _PT to be applied to the driving wheels of the vehicle according to the position α of the accelerator pedal AP and the forward speed v of the vehicle. M1 is attached. The data stored in the memory M1 defines a “drive capability map”. As described with reference to the system of FIG. 1, this map uniquely associates a predetermined value of power _PT to be applied to the drive wheels with the accelerator position α and the vehicle forward speed v.

The driving capability map stored in the memory M1 is basically a discrete numerical value of a predetermined curve for a specific engine E and a specific gear box G associated therewith, like the curve illustrated in FIG. It is an expression by. These curves, determined in advance, for example by the method described below, correlate the accelerator pedal position α with the power _PT to be applied to the drive wheels for each value of the forward speed v of the vehicle.

The driving capacity curve shown in FIG. 3 is determined by a method described below particularly for a specific engine-transmission unit having the following properties.
-Diesel cycle internal combustion engine with "common rail" fuel supply, Fiat DI / TCA M724, displacement 1.91 l.
-Fiat C510 automatic gearbox. The gear ratios for gears 1, 2, 3, 4, and 5 are 3.908, 2.238, 1.44, 1.03, and 0.767, respectively.
- accelerator ratio τ _p = 3.15.
-Transmission efficiency η _t = 0.95.
-Wheel turning radius R = 0.277 m.
The wheel moment of inertia J _W = 2.2465 Kg · m ² .

FIG 3a, for various accelerator position of the engine of the above alpha (%), showed a characteristic curve of torque C _M, expressed as a function of the rotational speed n (RPM).

  The torque characteristic curve shown in FIG. 3a is a “drive capability map” conventionally used in conventional engine control in which the command given from the accelerator pedal is substantially interpreted as a request for drive torque to the engine. , Corresponding substantially.

  The curves in FIG. 3a characterize the operation of the particular engine under consideration and can be derived experimentally by methods known to those skilled in the art.

FIG. 3a shows curves C _MMAX and C _MMIN that respectively define the maximum torque and the minimum torque that can be supplied from the engine at various rotational speeds.

ここで、
η_ｔはトランスミッション効率、
τ_ｐはアクスルトランスミッション比(axle transmission ratio)、
τ_ｉはギヤボックスＧで実現されるトランスミッション比、
Ｒは車輪の回転半径、である。 The drive torque C _M supplied from the engine E and the rotational speed ω _M of the engine shaft are related to the forward speed v of the vehicle and also related to the torque C _T applied to the wheels and transmitted to the ground according to the following formula. is doing.

here,
η _t is transmission efficiency,
τ _p is the axle transmission ratio,
τ _i is the transmission ratio realized in the gearbox G,
R is the turning radius of the wheel.

Applying the conversion equations (1), (2) to the curve of FIG. 3a along with the known relations relating power and torque, the forward speed of the vehicle at various accelerator positions α for the engine-transmission unit under consideration. The curve of FIG. 3b representing the power _PT applied to the wheel for each value of v is easily obtained. In order to avoid the complexity of the graphical representation, FIG. 3b shows the maximum power P _TMAXi (i = 1-5) and the minimum power P _TMINi (i = 1-5) for each gear ratio or transmission ratio of the gearbox G. The curve was shown.

  In addition, FIG. 3b specifically shows only the power curve corresponding to the accelerator pedal position α = 45%.

In order to define a driving capability map, expressed in terms of power applied to the driving wheels, relative to the forward speed of the vehicle at various accelerator pedal positions, it is suggested from FIG. 3b, for example, that the lower vehicle speed in the first gear. Then, in the driving ability map to be used, the original map C _M = f (n, α) is simply replaced with the corresponding variable P _T , v, whereby the characteristics regarding the start of the vehicle from the stationary state, and low It is advantageous to keep both the drive capability characteristics at speed unchanged. At higher speeds, at all gear ratios or transmission ratios, the power _PT applied to the wheels as vehicle speed v increases is substantially constant, or a part of the resistance to forward movement of the car. The driving capability map can be defined so that the curve gradually increases to compensate for the above.

With these criteria, for example, the drive capability map shown in FIG. 3 can be defined from the graph of FIG. 3B. This drive capability map is just one example of the myriad of possible maps that can be defined based on a wide variety of criteria. However, in general, in defining the drive capability map, the gear ratio selected for the transmission can be out of consideration. This independence ensures the continuity of torque when changing from one gear to another. In other words, in order to apply a power _PT corresponding to a given accelerator pedal position α and a given vehicle forward speed v to the drive wheels, a gear that includes the operating point under consideration within that region (power, speed). Any of them can be used equally.

In the system of FIG. 2, the driving capability map stored in the memory M1 indicates that the command given from the accelerator AP is applied to the power _PT applied to the wheels regardless of the gear ratio realized by the gear box G. It is configured to be converted.

Due to this fact, the selection of gear ratio or transmission ratio is no longer independent of subjective criteria that depend on the driving style of the car driver. In other words, the power applied to the wheel corresponds to the “request” specified by the driver with the accelerator pedal, and therefore the gear ratio for realizing the power has only a second significance. In this connection, the following restrictions are inevitably involved.
-For reasons of comfort (mainly noise) it is necessary to avoid as much as possible gear changes during high speed rotation of the engine E.
-For efficiency and comfort reasons, the frequency of gear changes should be kept as low as possible.

  If the above two requirements are met, the transmission ratio to be realized, i.e. the selection of the gear to be used, is determined according to a predetermined method for achieving a predetermined purpose, such as minimizing fuel consumption and / or exhaust emission. In particular, it can be performed with a certain degree of freedom.

  For example, for the purpose of minimizing fuel consumption, the fuel consumption per unit decreases with increasing load applied to the engine E, so as high a gear ratio as possible, ie, as low as possible, under any conditions. It is advantageous to use a transmission ratio. This implies the need to use the same power curve as the gear shift boundary for different gears.

The criteria that can be used to select the gear shift boundary for the purpose of minimizing fuel consumption are as follows, for example.
The transition between two adjacent gear ratios when raising and lowering the gear, i.e. the transmission ratio, over the range of the forward speed of the vehicle for a positive power _PT specified for the accelerator pedal position α. Defined by existing boundaries. Note that this must be accomplished within the maximum and minimum power that can be generated by the engine with the first and last gears.
-For gear upshifts, eg change from 2nd gear to 3rd gear, the gear shift boundary line corresponds to the power curve P _TMAX of the final gear, and in particular the drive capability of the vehicle at low speed rotation of the engine E Secure.
-For gear downshifts, eg change from 3rd gear to 2nd gear, in order to avoid the “over gear” phenomenon on the boundary, the corresponding upper gearshift (2nd gear to 3rd gear) It is necessary to specify a gear shift boundary line different from that specified for For this purpose, “hysteresis” is introduced by shifting the boundary line for the downward shift by an appropriate amount toward the low speed side of the vehicle forward speed.

  The graph of FIG. 4 shows boundaries for various gear shifts obtained based on the rules defined above for the engine-transmission unit described above.

  The gear shift boundary line shown in FIG. 4 can be rewritten into a corresponding discrete numerical value map as shown in Table 1 below, for example.

  It is advantageous to store the aforementioned map or table in a further memory M2 associated with the system control unit SCU (FIG. 2).

  A method of operating the above drive control system will be described below with reference to the flowchart of FIG.

The system control unit SCU is configured to repeatedly execute the following operations.
-Acquire the signal supplied from the sensors S1, Sn (Fig. 5, box 10). These signals indicate the position α% of the accelerator pedal AP and the gear ratio currently realized by the gear box G, that is, the transmission ratio τ _i .
Calculate the forward speed v of the vehicle based on the above equation (2) or obtain the speed value from the corresponding sensor (box 11).
-The value of the power _PT to be applied to the wheel by referring to the driving capability map stored in the memory M1 based on the acquired value of the accelerator pedal position α and the calculated value or acquired value of the vehicle forward speed v Decide. This determination of the value _PT generally involves interpolation between discrete numerical values stored in memory (box 12).
_{-Calculate the} drive torque C _MREF to be supplied from the engine E (box 13), based on the power value _PT determined in the above steps and by applying the above equation (1).
Based on the calculated or acquired value of the forward speed v and the determined power value _PT , the necessary gear ratio, i.e. the transmission ratio τ _n is determined by referring to the gear shift map stored in the memory M2 (box 14).
Check whether the transmission ratio τ _n is _equal to the currently realized transmission ratio τ _i (box 15).
When τ _n = τ _i , the system control unit SCU supplies a signal indicating the calculated value of the required drive torque C _MREF to the management unit ECU of the engine E. The engine management unit ECU controls the fuel injection so that the engine E supplies the drive torque C _MREF (box 16).
If τ _n is different from τ _i , the system control unit SCU requests the gear shift control unit GSCU to change the transmission ratio and sends a signal indicating the ratio τ _n to be realized. The system control unit SCU also supplies a torque target signal indicating a target drive torque value C _MREF to be supplied from the engine E to the engine management unit ECU and the gear shift control unit GSCU after completion of the gear shift process. The gear shift control unit GSCU supervises the change of the transmission ratio and controls the actuators A and B associated with the clutch F and the gear box G, respectively (box 17).

  The gear shift control unit GSCU is advantageously configured to supervise the gear shift using a simple mathematical model of the vehicle transmission that is effective in the gear shift process.

  This complexity of the gear shift control requires the operation of the engine E and the operations of the actuators A and B attached to the friction clutch F and the gear box G to coordinate the shift of the gear shift as comfortably and quickly as possible. caused by.

The gear or transmission ratio shifting operation basically includes the following steps.
- reduction of the driving torque C _M is supplied from the engine E, and, Hanaresetsu clutch F.
-Separation of the current gear and selection and coupling of a new gear.
-Re-engagement of clutch F and recovery of drive torque.

  To achieve gearshift comfort without degrading performance, the control system must reduce the time required for gearshifting as much as possible and take into account the driver's "feel". It is necessary to modulate the process of reducing and increasing the driving force.

  In the embodiment described below, this is accomplished by performing a “jerk-oriented” strategy, ie a strategy that reduces jerk, which is the time derivative of the vehicle's forward acceleration.

  In fact, statistical analysis reveals that the measured jerk is a good indicator of the degree of gear shift comfort felt by the passenger. Jerk is also a parameter related to the gear shift comfort felt by the driver. However, the driver's judgment is also influenced by the integrated value of the forward acceleration over the entire time required for the gear shift, which is also related to the sense of slowness.

In the drive control system according to the present invention, the system control unit SCU may be configured not only to determine the execution of the gear shift by the above-described method but also to specify the target value J _REF of the jerk during the gear shift process.

For this purpose, the system control unit SCU further stores a target jerk value, which is experimentally derived for the vehicle with the engine-transmission unit under consideration, as a function of the power _PT to be applied to the wheels. M3 (FIG. 2) may be accompanied.

Based on experimental measurements, for example, the target jerk value can be defined as a function of power _PT , for example, based on FIG. A value representing the jerk curve discretely as a function of the power _PT is stored in the memory M3.

In order to carry out the gear shift procedure, the system control unit SCU also accesses the memory M3 based on the required power P _T determined by the method described above and selects or determines the jerk target value selected or determined by interpolation. J _REF is specified for the gear shift control unit GSCU.

クラッチＦ離切時：

ここで（図６も参照）、
Ｃ_Ｍ，Ｊ_Ｍ，ω_Ｍは、それぞれ、エンジンＥの軸Ｍから供給されるトルク、エンジン軸Ｍの慣性モーメント、この軸の回転速度、であり、
Ｃ_Ｆ，Ｘ_Ｆは、それぞれ、摩擦クラッチＦからギヤボックスＧの１次軸Ｐに伝達されるトルク、摩擦クラッチＦの可動部材の位置、であり、
Ｃ_Ｒ，Ｊ_Ｐ，ω_Ｐは、それぞれ、ギヤボックスＧの１次軸Ｐ上の抵抗トルク、１次ギヤボックス軸Ｐ上の等価慣性モーメント、この１次軸の角速度、である。 The engine / transmission / drive wheel unit model used to determine in real time the drive torque supplied from the engine E and the torque transmitted to the drive wheels during the gear shift process is the basic diagram shown in FIG. This is based on the following mathematical formula.
When clutch F is engaged:

When releasing clutch F:

Where (see also FIG. 6),
C _M , J _M , and ω _M are the torque supplied from the shaft M of the engine E, the moment of inertia of the engine shaft M, and the rotational speed of this shaft, respectively.
C _F and X _F are the torque transmitted from the friction clutch F to the primary shaft P of the gear box G, and the position of the movable member of the friction clutch F, respectively.
C _R , J _P , and ω _P are the resistance torque on the primary shaft P of the gear box G, the equivalent moment of inertia on the primary gear box shaft P, and the angular velocity of the primary shaft, respectively.

The above equation (3), referring to (5), the resistance torque C _R, as a first approximation, may be considered to be in gear shifting process constant.

  Based on the equations (3) to (5), each process of the gear shift can be analyzed as follows.

Torque reduction process Referring to FIG. 8, this process continues from an initial time t ₀ to a later time t ₁ , and its length is t _U.

また、最終条件は以下のようになる。

During this process, the drive torque C _M must be gradually reduced from its initial value C _M0 to zero. Torque C _F transmitted by the friction clutch F also must be reduced to zero in synchronism, this time, as shown in the lower graph of Figure 8, it is maintained equal to the driving torque C _M. Therefore, in this torque reduction process, the initial conditions are as follows.

The final conditions are as follows.

The transition between t = t ₀ and t = t ₁ is as follows based on the above-described equation (3) and the assumption that the resistance torque _CR is constant.

In the formula (6), the moment of inertia J _P is that corresponding to the transmission ratio tau _i that is implemented at the beginning of the gear shifting process.

ここで、ω_Ｗ，Ｒは、それぞれ、駆動輪の角速度および回転半径である。 Longitudinal acceleration a _x of the vehicle, the angular acceleration of the shaft M of the engine E, relation represented by the following formula.

Here, ω _W and R are the angular velocity and the rotation radius of the drive wheel, respectively.

Jerk is the time derivative of the longitudinal acceleration a _x. Therefore, it becomes as follows.

During this process, in order for the jerk to remain constant and equal to the predetermined target value J _REF , the drive torque C _M must be reduced based on a linear curve. At the completion of the torque reduction process, the torque C _F transmitted by the friction clutch F must also be zero, so the torque C _F has the same linear reduction curve as shown in the left part of the lower graph of FIG. Applied. Therefore, it becomes as follows.

Period (length) T _U of the torque reduction process is determined uniquely by the formula (8) described above based on a predetermined jerk target value J _REF. Therefore, it becomes as follows.

During this process, the friction clutch F is disconnected, the gear ratio τ _i is disconnected, and the gear ratio τ _n is engaged.

During these operations, the angular velocity of the primary gearbox shaft P is within a time which depends on the characteristics of the actuator A associated with the performance and the friction clutch F synchronizer, the ω _W τ _i ω _W τ to _n And change.

At the completion of this process:

Torque re-application process This process (FIG. 8) has a period T _L = t ₃ −t ₂ .

During this process, the drive torque C _M and the torque C _F transmitted by the friction clutch F reach the final value C _MREF calculated in advance and the angular velocity ω _M of the engine shaft M and the primary shaft P of the gear box G. Must be synchronized with the angular velocity ω _{P of} FIG. 5 (box 13 in FIG. 5).

また、最終条件は以下のようになる。

Therefore, in this process, the initial conditions are as follows.

The final conditions are as follows.

このＪ_Ｐは、新たなギヤ比τ_ｎに基づいて、このとき計算された値である。 The transition between t ₂ ~t _3, and the above equation (5), the resistance torque C _R is based on on the assumption that equal to the value C _R0 with a constant, as follows.

This _JP is a value calculated at this time based on the new gear ratio τ _n .

During this process, longitudinal acceleration a _x of the motor vehicle is as follows.

So the jerk looks like this:

To maintain the jerk during this process to a constant value, both of the torque C _F transmitted by the drive torque C _M and the friction clutch F, as shown in the right part of the lower graph of Figure 8, the linear It is necessary to control based on the curve. At this time, it becomes as follows.

The total period T _L of the torque re-application process is based on the equations (14) and (15), and the jerk must take the target value J _REF , and is as follows.

The time length T _M represents a period necessary for the shaft M of the engine E to decelerate by the torque transmitted by the clutch F. The length of this period is determined based on the constraints associated with the synchronization of the angular velocity omega _P of the angular velocity omega _M and the primary gearbox shaft P of the engine shaft M.

Thus, the length of the period _{T M} is the above equation (4) can be calculated by solving the two equations corresponding to the time integral of _t 2 ~t ₃ (5). The solution is as follows.

Engine management unit ECU and gear-shift control unit GSCU, compared torque C _F transmitted by the drive torque C _M and the clutch F, configured to execute the various rules described above.

However, the automatic drive control system described above may also be configured to be able to “manually” control the servo-assisted gearbox G substantially according to the prior art. For this purpose, a selector M / A (FIG. 2) that can be manually operated by the user to select the type of operation (manual or automatic) and a signal indicating the transmission ratio that the driver wishes to perform are supplied to the unit SCU. and additional sensor devices S _M, but is connected to the system control unit SCU. Sensor S _M, the joystick type device, pushbutton, vertical selection lever, etc., may be a position sensor for device cooperating known type for selecting the transmission ratio.

In the “manual” operating mode, the system control unit SCU does not execute the control method described above. The system control unit SCU may be transferred instructions the driver in order to obtain the driving torque C _M corresponding to the accelerator pedal position α from the engine E is supplied from the accelerator pedal AP to the unit ECU, and the transmission ratio to be the driver has performed The signal shown is only transferred to the gear shift control unit GSCU.

  The architecture of the control system shown in FIG. 2 is just one example of various possible architectures.

  Another possible architecture is shown in FIG. In the figure, the already explained parts and elements are denoted by the same reference numerals as those described above.

In the configuration shown in FIG. 9, the function of the control unit SCU of FIG. 2 is divided into an engine E control unit ECU and a gear shift control unit GSCU. These are connected to each other by a communication network CN such as a CAN type. In particular, the memory M1 provided with the driving capability map is attached to the engine control unit ECU. A sensor S1 (accelerator pedal AP position α) and a sensor S2 (angular velocity ω _M of the shaft M of the engine E) are also connected to the ECU.

On the other hand, when the memory M2 (gear shift map) and the memory M3 (jerk map) exist, the sensor Sn (realized ratio τ _i ), the selector M / A, the sensor S _M , and the gear shift control unit GSCU. Accompanying.

During automatic operation, the unit ECU is a forward speed v is calculated, to determine the value of the power _{P T,} calculates the torque _{C MREF} corresponding thereto. Also, the unit ECU transmits the values of the velocity v and the power _{P T} to the unit GSCU. This unit GSCU determines the jerk target value J _REF together with the transmission ratio τ _n to be realized, and then controls the change of the transmission ratio in cooperation with the unit ECU substantially as described above, if necessary. To do.

  It is of course possible to adopt other architectures by changing the task sharing among the control units used or by using a single control unit that controls the entire system.

Claims (7)

Control means for operating the engine in such a manner that the engine (E) supplies a driving torque (C _M ) that varies according to predetermined measurement parameters, in particular the position (α) of the accelerator pedal (AP). (ECU, GSCU, SCU) with an internal combustion engine (Engine E),
Sensor means (S1) for supplying electrical signals indicating the position (α) of the accelerator pedal (AP) and the rotational speed (ω _M ) of the shaft (M) of the engine (E) or the forward speed (v) of the vehicle, respectively. , S2),
A vehicle drive control system comprising:
The control means (ECU, GSCU, SCU)
From the sensor means (S1, S2), the position (α) of the accelerator pedal (AP) and the rotational speed (ω _M ) of the shaft (M) of the engine (E) or the forward speed (v) of the vehicle are acquired. And
Based on the measured position (α) of the accelerator pedal (AP) and the calculated or obtained forward speed (v) of the vehicle, the power (P _T ) to be applied to the drive wheels is determined. Has been
The control means (ECU, GSCU, SCU)
Based on the value determined as the power (P _T ) to be applied to the driving wheel and the forward speed (v) of the automobile, the driving torque (C _MREF ) to be supplied by the engine (E) is calculated correspondingly. The engine (E) is controlled to supply the drive torque (C _MREF ) calculated in this way,
The system comprises first memory means (M1),
The first memory means is associated with the control means, and power to be applied to the driving wheels of the automobile based on the position (α) of the accelerator pedal (AP) and the forward speed (v) of the automobile ( Data for defining P _T ), and
The control means is configured to determine the power (P _T ) to be applied to the drive wheels based on the data stored in the first memory means (M1).
The automobile drive control system further includes:
An input shaft (P) coupled to the shaft (M) of the engine (E) by the servo assist clutch (F), and first and second electrically associated with the gear box (G) and the clutch (F), respectively. A servo assist gearbox (G) comprising actuator means (B, A) to be driven;
Further sensor means (Sn) for supplying an electrical signal indicative of the transmission ratio (τ) realized by the gear box (G),
The control means is configured to execute an automatic drive control procedure based on a position (α) of an accelerator pedal (AP),
Said control means are in particular
From the sensor means (S1, S2, Sn), the position (α) of the accelerator pedal (AP), the rotational speed (ω _M ) of the shaft (M) of the engine (E) or the forward speed (v) of the vehicle, and the gear The transmission ratio (τ _M ) realized by the box (G),
Calculate or obtain the forward speed (v) of the car,
Based on the measured position (α) of the accelerator pedal (AP) and the forward speed (v) of the vehicle, the power (P _T ) to be applied to the drive wheels is determined by a predetermined method.
Based on the value determined as the power (P _T ) to be applied to the driving wheel and the forward speed (v) of the automobile, the driving torque (C _MREF ) to be supplied by the engine (E) is calculated correspondingly. And
The transmission ratio (τ _n ) to be realized by the gearbox (G) by a predetermined method based on the value determined as the power (P _T ) to be applied to the drive wheels and the forward speed (v) of the automobile. Decide
Check if the transmission ratio (τ _n ) to be realized corresponds to the realized transmission ratio (τ _i ),
If so, the engine (E) is controlled to supply the calculated drive torque (C _MREF ), and
If not supported, it controls the implementation of the change of the transmission ratio to be achieved to (tau _n), at the time of completion of the change operation of the transmission ratio to be realized (tau _n), calculated drive To control the engine (E) to supply a drive torque substantially equal to the torque (C _MREF ),
A drive control system for an automobile configured. The control system according to claim 1, comprising second memory means (M2).
The second memory means is associated with the control means, and is realized by a gear box (G) based on the power (P _T ) to be applied to the drive wheels and the forward speed (v) of the automobile. Storing the data for defining the transmission ratio, ie the gear (τ _n ) to be
The control system is configured to determine a transmission ratio (τ _n ) to be realized based on data stored in the second memory means (M2). The control system according to claim 1 or 2,
The control means includes
Based on the value determined as the power to be applied to the driving wheel (P _T ), the target value (J _REF ) of time differentiation of the forward acceleration (a _x ) of the vehicle is determined by a predetermined method,
Generating a target signal indicating a target driving torque (C _MREF );
In order to control the change to the transmission ratio (τ _n ) to be realized so that the time derivative of the forward acceleration (a _x ) of the vehicle remains substantially constant and equals the target value (J _REF ),
Configured system. Control system according to claim 3, comprising third memory means (M3),
The third memory means is associated with the control means, and stores a predetermined value of time differentiation of the forward acceleration (a _x ) of the automobile as a function of the power (P _T ) to be applied to the drive wheels. System. The control system according to claim 3 or 4,
The control means includes
In the gear shift process, the drive torque (C _M ) supplied from the engine (E) and the torque (C _F ) transmitted from the clutch (F) to the gear box (G) change substantially based on linear rules, respectively. Thus, the control system is configured to control the engine (E) and the actuator means (A, B) respectively associated with the clutch (F) and the gear box (G). 3. The control system according to claim 2, wherein the second memory means (M2) stores data indicating a gear shift boundary line in ground power / advance speed-plane (P _T / v),
The boundary for a shift from one gear to an adjacent high or low gear is different from the boundary for the opposite shift. A control system according to any one of claims 1 to 6, comprising manually operated selector means (M / A),
The selector means supplies a selective signal for manual drive control or automatic drive control to the control means.

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