JP2007163306A - Automatic drive controller in vehicle tester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic drive controller in a vehicle tester that can make the actual vehicle speed follow a vehicle speed variation pattern at a high accuracy and alter the accelerator pedal opening with an operation approximated to an accelerator pedal operation by an actual human being. <P>SOLUTION: Acceleration information handled by a feedforward system 2 is previously stored in a target acceleration generator 14 in an engine bench tester for automatically calculating throttle opening θ. The accelerator pedal opening θis determined by adding accelerator pedal opening corrective value θb calculated by a feedback system 3 to basic accelerator pedal opening θa determined from the acceleration information stored in the target acceleration generator 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an automatic driving control device for matching a driving state with a predetermined test pattern in a vehicle tester (such as a chassis dynamometer or an engine bench tester) that performs a dynamic driving performance test of a vehicle or an engine. .

  Conventionally, as disclosed in, for example, Patent Document 1 and Patent Document 2 below, a vehicle tester such as a chassis dynamometer or an engine bench tester is used to perform a vehicle running performance test or an engine operation test. Simulated operation is performed. In this simulated operation, tests such as fuel consumption rate and exhaust emission performance are performed by driving a plurality of actuators individually by hydraulic pressure, air pressure, motor, etc., and operating an accelerator pedal, a transmission, and the like.

  By the way, in the simulated operation, it is necessary to drive the vehicle or the engine so as to follow a preset driving pattern (test pattern). For this purpose, the control logic described below is adopted as a method for controlling the accelerator pedal opening.

  FIG. 5 shows a control block for determining the accelerator pedal opening for causing the traveling speed of the vehicle (hereinafter simply referred to as the vehicle speed) to follow a predetermined driving pattern (vehicle speed change pattern). As shown in FIG. 5, the control block includes feedback for compensating for errors in the feedforward system A and the accelerator pedal opening (basic accelerator pedal opening θa) obtained in the feedforward system A. System B is provided.

  First, in the feedforward system A, the basic accelerator pedal opening θa is calculated by a differentiator a, a vehicle inertia moment multiplying unit b, a tire radius multiplying unit h, a road resistance calculating unit c, a gear ratio multiplying unit d, and an NT map e. The Specifically, information on the target vehicle speed Vtrg is input to the differentiator a in accordance with the driving pattern, and the target acceleration Atrg is calculated by differentiating the target vehicle speed Vtrg. On the other hand, the vehicle inertia moment multiplication unit b multiplies a transfer function according to the inertia moment such as the vehicle weight, thereby calculating the target driving force Ftrg. Further, the tire radius multiplication unit h multiplies the target driving force Ftrg by the tire radius, and the resistance (R / L: road resistance, air resistance, etc.) that increases as the vehicle speed increases and the tire radius ( The value obtained by multiplying the tire effective diameter) (the value calculated by the road resistance calculation unit c) is multiplied, and the gear ratio (gear ratio in a transmission, a differential gear, or the like) as a test condition is multiplied by the gear ratio multiplication unit d. The target torque Ttrg is calculated by further multiplying at. Then, the target torque Ttrg calculated as described above and the current actual engine speed are input to the NT map e, and the accelerator pedal opening θa for obtaining the target torque Ttrg is obtained from the NT map e. In this way, the basic accelerator pedal opening degree θa is calculated.

  On the other hand, the feedback system B includes a PID control unit f, and a correction value θb for the basic accelerator pedal opening θa is calculated. As the calculation in the feedback system B, first, the deviation between the target vehicle speed Vtrg input according to the driving pattern and the actual vehicle speed (feedback vehicle speed) Vr sensed or calculated (calculated from the engine speed, gear ratio, etc.). ΔV is calculated, and the deviation ΔV is subjected to PID (proportional / integral / derivative) control by the PID control unit f, whereby the accelerator pedal opening correction value θb corresponding to the deviation ΔV is obtained. That is, the accelerator pedal opening correction value θb for bringing the actual vehicle speed Vr close to the target vehicle speed Vtrg is obtained.

The accelerator pedal opening degree θ is determined by adding the basic accelerator pedal opening degree θa and the accelerator pedal opening correction value θb obtained as described above, and the signal is input to the pedal actuator g. The accelerator pedal is operated to the accelerator pedal opening θ so that the actual vehicle speed Vr can be brought close to the target vehicle speed Vtrg.
JP 11-258119 A JP 2003-214990 A

  However, in the conventional control method of the accelerator pedal opening described above, the target vehicle speed Vtrg input to the differentiator a every predetermined time (for example, 1 sec) in the feedforward system A is subjected to approximate differentiation processing in real time. Since the target acceleration Atrg is calculated, there are the following problems.

  That is, the above-described various arithmetic processes are performed based on the target acceleration Atrg calculated at a predetermined time interval to calculate the accelerator pedal opening θ, and the accelerator pedal is operated at the predetermined time interval. The accelerator pedal cannot be operated. That is, an operation different from an actual accelerator pedal operation by a human is performed.

  In order to solve this problem, the “smoothing process” is performed by the transfer function [Ts / (Ts + 1)] of the first-order delay system differentiator, and the accelerator pedal operation amount controlled at the predetermined time interval is smoothed. Has been done. However, when the “smoothing process” by the first-order lag differentiator is performed as described above, the accelerator pedal operation (in order to obtain the calculated accelerator pedal opening θ) obtained in the feedforward system A with respect to the target vehicle speed Vtrg. Accelerator pedal operation) will be delayed.

  In particular, when the signal of the target vehicle speed Vtrg is analog data, a small noise signal present in the vehicle speed signal greatly affects the differentiated acceleration signal. In other words, if acceleration calculation is performed when the acceleration is momentarily reduced due to the noise signal, the accelerator pedal opening corresponding to the actually required acceleration (required target acceleration Atrg) is set. It becomes impossible to calculate. For this reason, when the signal of the target vehicle speed Vtrg is analog data, processing of this signal is performed with a low-pass filter to suppress the influence of noise. For this filter processing, further accelerator pedal operation is performed. Will be delayed.

  As described above, in the situation where a delay occurs in the accelerator pedal operation, the integral term (I term) of the PID control becomes remarkably large with this delay, and the calculated operation amount of the accelerator pedal opening (by feedback control) The corrected operation amount of the accelerator pedal opening) is larger than the required operation amount, and unnecessary feedback correction is performed. As a result, the accelerator pedal is turned back (compared to actual human accelerator pedal operation) Therefore, useless operations) frequently occur, and it becomes difficult to converge the actual vehicle speed to the target vehicle speed.

  Note that the above-described problem occurs not only when the accelerator pedal is operated to cause the vehicle speed to follow a predetermined driving pattern, but also when the throttle valve is operated to cause the vehicle speed to follow the predetermined driving pattern. Similarly, when the engine speed is made to follow a predetermined operation pattern by operating the accelerator pedal or the throttle valve, it is difficult to make the engine speed follow the speed change pattern with high accuracy.

  The present invention has been made in view of such points, and the object of the present invention is to make the actual vehicle speed follow the vehicle speed change pattern with high accuracy or to increase the actual engine speed to the engine speed change pattern. It is possible to follow with accuracy, and the accelerator pedal opening (in a tester that directly controls the opening of the throttle valve by an operation approximate to the actual human accelerator pedal operation) It is an object of the present invention to provide an automatic operation control device in a vehicle tester capable of changing a throttle valve opening degree (linked with a human accelerator pedal operation).

-Summary of invention-
The solution of the present invention taken to achieve the above-mentioned object is that the information handled in the feedforward system is transmitted to the automatic operation control device for automatically controlling the throttle opening, the speed signal (vehicle speed and engine speed). ) Is not acceleration signals obtained by differential processing but acceleration information stored in advance, so that the delay in throttle operation associated with conventional differential processing is eliminated.

-Solution-
First, the following configuration can be cited as a solution means for controlling the throttle opening so that the vehicle speed follows a predetermined driving pattern. A feedforward system for obtaining a “feedforward control value” by feedforward control, and a feedback system for obtaining a “feedback correction value” for bringing the actual vehicle speed closer to the target vehicle speed based on a deviation between the target vehicle speed and the actual vehicle speed. Alternatively, when performing a simulated engine operation, based on the value obtained by adding the “feedback correction value” obtained by the feedback system to the “feedforward control value” obtained by the feedforward system, Assuming an automatic driving control device in a vehicle tester to determine "." This automatic driving control device is provided with a target acceleration storage means in which information on temporal changes in vehicle target acceleration corresponding to the simulated driving of the vehicle or engine is stored in advance. The feedforward system receives the vehicle target acceleration signal from the target acceleration storage means and obtains a “feedforward control value”.

  Moreover, the following structure is mentioned as a solution means for controlling the throttle opening so that the engine speed follows a predetermined operation pattern. A feedforward system for obtaining a “feedforward control value” by feedforward control and a “feedback correction value” for bringing the actual engine speed closer to the target engine speed based on the deviation between the target engine speed and the actual engine speed. When performing a simulated operation of the vehicle or engine, the “feedback correction value” obtained by the feedback system is added to the “feedforward control value” obtained by the feedforward system. An automatic driving control device in a vehicle tester that determines the “throttle opening” based on the value is assumed. This automatic operation control device is provided with a target acceleration storage means in which information on temporal changes in the engine speed target acceleration corresponding to the simulated operation of the vehicle or engine is stored in advance. The feedforward system receives the engine speed target acceleration signal from the target acceleration storage means and obtains a “feedforward control value”.

  The “throttle opening” in these solutions means not only the case where the throttle valve opening provided in the engine intake system is directly adjusted by a throttle motor, but also the accelerator opening for adjusting the throttle valve opening. This also includes adjusting the pedal opening (depressing amount of the accelerator pedal).

  With these specific items, the throttle operation is compared with the conventional method of calculating the target acceleration by differentiating the target vehicle speed every predetermined time in the feedforward system and determining the throttle opening based on the calculated target acceleration. The time delay can be eliminated. That is, information on temporal changes in target acceleration (target acceleration of the vehicle or target acceleration of the engine speed) corresponding to the simulated driving is stored in advance in the target acceleration storage means, and this information is stored in the feedforward system. By processing directly, the time delay of the throttle operation can be eliminated, and the operation almost identical to the actual human accelerator pedal operation (including the change in the throttle opening accompanying it) can be executed and the reliability of the simulated operation can be improved. Can be increased.

  Among the above-described solutions, the specific configuration in which the throttle opening is controlled so that the vehicle speed follows a predetermined driving pattern includes the following. That is, the “feedforward control value” is the basic throttle opening (θa) obtained based on the vehicle target acceleration signal received from the target acceleration storage means, while the “feedback correction value” is the target vehicle speed (Vtrg). ) And the actual vehicle speed (Vr) is a throttle opening correction value (θb) obtained based on a deviation (ΔV).

  As a more specific configuration, a feedforward system (2), a feedback system (3), and an adding means (6) are provided, and the feedforward system (2) corresponds to a simulated operation of a vehicle or an engine. A vehicle target acceleration (Atrg) signal is received from a target acceleration storage means (14) in which information on temporal changes in the vehicle target acceleration (Atrg) is stored in advance, and this vehicle target acceleration (Atrg) is multiplied by the vehicle inertia moment. The vehicle inertia moment multiplication unit (21) for calculating the target driving force (Ftrg) and the target torque (Ftrg) calculated based on the target driving force (Ftrg) calculated by the vehicle inertia moment multiplication unit (21). An NT map (24) for obtaining a basic throttle opening (θa) from Ttrg) and the current engine speed is provided. Further, the feedback system (3) is provided with a PID control unit (34) for calculating a throttle opening correction value (θb) by performing PID control of a deviation (ΔV) between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr). Prepare. Then, the adding means (6) adds the throttle opening correction value (θb) obtained by the feedback system (3) to the basic throttle opening (θa) obtained by the feedforward system (2). Thus, the throttle opening (θ) is determined.

  The following configurations are also within the scope of the technical idea of the present invention. That is, a feedforward system (2), a feedback system (3), and an opening calculation system (4) are provided, and the feedforward system (2) is provided with a vehicle target acceleration corresponding to a simulated operation of the vehicle or engine ( A target acceleration storage means (14) in which information on temporal change of (Atrg) is stored in advance is connected. In addition, a PID control unit (34) that calculates a corrected vehicle speed value (V1) by performing PID control on a deviation (ΔV) between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr) in the feedback system (3); An acceleration correction value calculator (35) for calculating the basic correction acceleration (A1) by dividing the corrected vehicle speed value (V1) calculated by the PID control unit (34) by the time (Tconst) required for correcting the vehicle speed; And gain setting means (36) for correcting the basic corrected acceleration (A1) calculated by the acceleration correction value calculator (35) with a predetermined gain (Gv) to obtain the corrected acceleration (A2). Further, the target acceleration (Atrg) is added to the opening calculation system (4) by adding the vehicle target acceleration (Atrg) from the feedforward system (2) and the corrected acceleration (A2) obtained by the feedback system (3). '), And the vehicle inertia moment for calculating the target driving force (Ftrg) by multiplying the target acceleration (Atrg') obtained by the acceleration adder (20) by the vehicle inertia moment. The throttle opening is obtained from the target torque (Ttrg) calculated based on the target driving force (Ftrg) calculated by the multiplier (41), the vehicle inertia moment multiplier (41), and the current engine speed. NT map (44). The gain setting means (36) makes the gain (Gv) for correcting the basic correction acceleration (A1) variable, and the gain setting means (36) deviates between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr). In the situation where this deviation increases, the correction acceleration (A2) is set to a gain obtained as a larger value than the basic correction acceleration (A1), while this deviation decreases. In the situation, the corrected acceleration (A2) is set to a gain obtained as a smaller value than the basic corrected acceleration (A1).

  According to this specific matter, as in the case of the solution described above, it is not necessary to obtain the acceleration signal by differential processing of the speed signal, so that the time delay of the throttle operation is eliminated and the actual human accelerator pedal operation is simplified. Matching actions can be performed. In addition, it is possible to set the throttle opening with higher convergence compared to the case where the gain of the feedback correction value is adjusted based only on the deviation value between the target vehicle speed and the actual vehicle speed, and the NT map. Before the throttle opening is determined by (44), by adding the corrected acceleration (A2) obtained by the feedback system to the vehicle target acceleration (Atrg) from the feedforward system, the NT map ( 44), the throttle opening is determined as a value including the corrected acceleration (A2). For this reason, it becomes possible to make the actual vehicle speed follow the vehicle speed change pattern with high accuracy without being affected by the difference in engine speed and engine characteristics, and the operation substantially matches the actual human accelerator pedal operation. The reliability of the simulated operation can be improved.

  In the present invention, for the automatic operation control device for automatically controlling the throttle opening, information handled in the feedforward system is not an acceleration signal obtained by differentiating a speed signal (vehicle speed or engine speed), The acceleration information stored in advance is used to eliminate the throttle operation delay associated with the conventional differential processing. For this reason, the time delay of the throttle operation can be almost eliminated, and the throttle opening (accelerator pedal opening) is automatically made to follow the change pattern (vehicle speed change pattern or engine speed change pattern) with high accuracy. Control becomes possible, and it is possible to execute an operation substantially coinciding with an actual human accelerator pedal operation (including a change in the throttle opening associated therewith), and the reliability of the simulated operation can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment demonstrates the case where this invention is applied to an engine bench tester as a vehicle tester. In this embodiment, in order to change the vehicle speed (vehicle speed) according to a predetermined test condition (driving pattern), an engine performance test or the like is performed while the accelerator pedal opening is controlled (opening is adjusted by an actuator). The case will be described.

<First Embodiment>
-Outline configuration of engine bench tester-
FIG. 1 shows a schematic configuration of a control block of the engine bench tester according to the present embodiment. As shown in FIG. 1, in the engine bench tester according to the present embodiment, an engine E to be tested is placed, and a vehicle (virtual vehicle) is placed against an output shaft E1 (crankshaft) of the engine E. ) To a motor M for reproducing the load applied to the engine E in a pseudo manner. That is, the motor M reproduces the vehicle load (load such as the vehicle body weight and running resistance), and this vehicle load acts on the output shaft E1 of the engine E in a pseudo manner. In this state, the engine E is driven, and the virtual vehicle speed (vehicle speed calculated based on the engine speed, gear ratio, etc.) and the load by the motor M are changed along a predetermined operation pattern (verification pattern). Tests such as the fuel consumption rate and exhaust emission performance of the engine E are conducted.

  The engine bench tester includes an operation pattern generator 1 that outputs various operation conditions such as a target vehicle speed that is the operation pattern, a feedforward system (feedforward circuit) 2, and a basic that is output from the feedforward system 2. A feedback system (feedback circuit) 3 for compensating for an error in the accelerator pedal opening θ is provided. Each will be described below.

(Operation pattern generator 1)
The driving pattern generator 1 includes a target vehicle speed generator 11, a running resistance generator 12, and a shift speed generator 13. Further, as a feature of the present embodiment, the driving pattern generator 1 includes a target acceleration generator (target acceleration storage means) 14.

  The target vehicle speed generator 11 transmits a target vehicle speed signal Vtrg corresponding to the driving pattern to the feedback system 3.

  The travel resistance generator 12 is connected to a load resistance calculation unit 22 of the feedforward system 2 to be described later, and sets a set travel resistance (a travel resistance corresponding to a road surface frictional resistance, air resistance, etc.) according to the traveling vehicle speed. The converted signal is transmitted to the load resistance calculation unit 22.

  The gear stage generator 13 is connected to a gear ratio multiplication unit 23 of the feedforward system 2 to be described later, and transmits information on a set gear stage (transmission change position) corresponding to the operation pattern to the gear ratio multiplication unit 23. It is like that.

  The target acceleration generator 14 stores (stores) information on the target acceleration Atrg for obtaining the target vehicle speed Vtrg corresponding to the driving pattern, and transmits the target acceleration Atrg information to the feedforward system 2. It has become. Information on the target acceleration Atrg stored in the target acceleration generator 14 is obtained by previously converting an acceleration change pattern in which the vehicle speed matches the vehicle speed change pattern of the simulated operation as information on the target acceleration Atrg. This data is stored in the target acceleration generator 14.

  Various signals transmitted from the operation pattern generator 1 are also transmitted to the motor controller 5 for controlling the motor M attached to the output shaft E1 of the engine E. That is, control of the motor M by the motor controller 5 (adjustment of the load acting on the engine E from the motor M) is performed so that a load corresponding to the operation pattern signal transmitted from the operation pattern generator 1 acts on the engine E. It has come to be. The motor M also creates a load for creating the NT map 24 when the NT map 24 described later (a map for determining the accelerator pedal opening from the target torque and the engine speed) is created. It is controlled by the motor controller 5 so as to act. The operation of creating the NT map 24 will be described later.

(Feed forward system 2)
The feedforward system 2 calculates a basic accelerator pedal opening degree θa based on the target acceleration Atrg transmitted from the target acceleration generator 14, and includes a vehicle inertia moment multiplication unit 21, a tire radius multiplication unit 25, a road A resistance calculation unit 22, a gear ratio multiplication unit 23, and an NT map 24 are provided.

  The vehicle inertia moment multiplying unit 21 has a transfer function corresponding to the vehicle inertia moment such as the vehicle weight, and calculates the target driving force Ftrg by multiplying the target acceleration Atrg by the vehicle inertia moment. .

  The tire radius multiplication unit 25 multiplies the target driving force Ftrg by the tire radius. The road resistance calculation unit 22 calculates a value obtained by multiplying a resistance (R / L: road resistance, air resistance, etc.) that increases as the vehicle speed increases and a tire radius (tire effective diameter). Thus, this value is multiplied by the target driving force Ftrg. The basic target torque T1 is calculated by multiplying the target driving force Ftrg by the tire radius multiplier 45 and the load resistance calculator 42.

  The gear ratio multiplication unit 23 calculates the target torque Ttrg by multiplying the basic target torque T1 by the gear ratio to be tested.

  The NT map 24 receives the target torque Ttrg calculated in this way and the current engine speed (engine speed detected by an engine speed detector 31 described later), and the basic accelerator pedal is obtained from these values. The opening degree θa is obtained.

(Feedback system 3)
The feedback system 3 includes an engine speed detector (engine speed sensor) 31, a vehicle speed calculation unit 32, a vehicle speed comparator 33, and a PID control unit 34.

  The engine speed detector 31 is disposed opposite to the Ne rotor 31a attached to the output shaft E1 of the engine E, and a pulse signal is generated along with the passage of the outer peripheral protrusion of the Ne rotor 31a due to the rotation of the output shaft E1. And the rotational speed of the output shaft E1, that is, the engine rotational speed is detected based on the pulse signal.

  The vehicle speed calculation unit 32 receives the engine speed signal from the engine speed detector 31, receives information on the engine speed, information on the speed stage transmitted from the speed stage generator 13, and tire radius (virtual speed). The actual vehicle speed Vr (virtual actual vehicle speed: calculated vehicle speed) is calculated from the tire effective radius.

  The vehicle speed comparator 33 compares the target vehicle speed Vtrg from the target vehicle speed generator 11 with the actual vehicle speed Vr calculated by the vehicle speed calculation unit 32, and calculates the deviation ΔV.

  The PID control unit 34 obtains an accelerator pedal opening correction value θb corresponding to the deviation ΔV by performing PID (proportional / integral / derivative) control on the deviation ΔV calculated by the vehicle speed comparator 33. That is, the accelerator pedal opening correction value θb for bringing the actual vehicle speed Vr close to the target vehicle speed Vtrg is obtained.

  The accelerator pedal opening θ is determined by adding the basic accelerator pedal opening θa and the accelerator pedal opening correction value θb obtained as described above by the adder (adding means) 6, and the signal is By inputting to the pedal actuator 7, the accelerator pedal is operated to the accelerator pedal opening degree θ so that the actual vehicle speed Vr can be brought close to the target vehicle speed Vtrg.

-Accelerator pedal opening control operation-
Next, the control operation of the accelerator pedal opening degree in the engine bench tester configured as described above will be specifically described.

  First, the NT map 24 is created prior to the accelerator pedal opening control operation. In this NT map creation operation, the accelerator pedal opening is increased from 0% to 100% every 10%, and the relationship between the output torque of the engine E and the engine speed is monitored. Specifically, the NT map 24 is created by repeating the operation of detecting the output torque and obtaining the performance curve with the accelerator pedal opening and the engine speed fixed.

  The accelerator pedal opening control operation during the performance test of the engine is performed in a state in which the engine E is operated, in response to a command from the operation pattern generator 1, the feedforward system 2 is supplied with the target acceleration Atrg from the target acceleration generator 14. The target vehicle speed Vtrg is input to the feedback system 3 from the target vehicle speed generator 11.

  In the feedforward system 2, as described above, the target acceleration Atrg is multiplied by the vehicle inertia moment in the vehicle inertia moment multiplier 21, the tire radius is multiplied in the tire radius multiplier 25, and the resistance ( (R / L: road resistance, air resistance, etc.) multiplied by the tire radius and the gear ratio multiplication unit 23 performs a calculation process of the gear ratio to calculate the target torque Ttrg. Further, the calculated target torque Ttrg and the current engine speed (the engine speed detected by the engine speed detector 31) are input to the NT map 24, and the basic accelerator pedal opening θa is obtained from these values. .

  On the other hand, in the feedback system 3, a deviation ΔV between the target vehicle speed Vtrg and the actual vehicle speed (calculated actual vehicle speed) Vr is calculated by the vehicle speed comparator 33, and this deviation ΔV is PID-controlled by the PID control unit 34 and the deviation ΔV Accelerator pedal opening correction value θb corresponding to is obtained. That is, the accelerator pedal opening correction value θb for bringing the actual vehicle speed Vr close to the target vehicle speed Vtrg is obtained.

  The accelerator pedal opening θ is determined by adding the basic accelerator pedal opening θa and the accelerator pedal opening correction value θb obtained as described above by the adder 6, and the signal is sent to the pedal actuator 7. As a result of the input, the pedal actuator 7 operates the accelerator pedal so that the accelerator pedal opening becomes the opening value θ.

  According to the accelerator pedal opening control operation as described above, it is not necessary to perform a process of differentiating the target vehicle speed and calculating the target acceleration in the feedforward system 2. For this reason, the time delay of an accelerator pedal operation can be eliminated. That is, the target acceleration generator 14 stores in advance information on the temporal change in the target acceleration corresponding to the simulated operation, and this information is directly processed by the feedforward system 2 so that the accelerator pedal operation time can be obtained. It is possible to eliminate the delay and to execute an operation substantially coinciding with an actual human accelerator pedal operation (including a change in the throttle opening associated therewith), and to improve the reliability of the simulated operation.

-Experimental example-
Examples of experiments conducted to confirm the above effects will be described below. In this experiment, the accelerator pedal opening degree control for changing the vehicle speed along a predetermined driving pattern (for example, LA # 4 mode) was performed, and the result is shown in FIG. A rectangular wave (pulse wave) in FIG. 2 is a differential operation value in a conventional method (a method of calculating a target acceleration by differentiating a target vehicle speed at a predetermined time (1 sec) interval in a feed forward system), , The temporal change of the vehicle acceleration due to the accelerator pedal operation smoothed by “smoothing processing” of the differential operation value is shown. On the other hand, the solid line in FIG. 2 shows the temporal change in the vehicle acceleration when the accelerator pedal opening degree control is performed by the control block according to the embodiment described above.

  As can be seen from FIG. 2, in the control by the control block according to the prior art, there is a vehicle acceleration delay due to the delay in the accelerator pedal operation. On the other hand, in the control by the control block according to the embodiment of the present invention, it is understood that the delay of the vehicle acceleration is eliminated and the accelerator pedal operation is not delayed. The effects of the present invention were confirmed by the above experimental examples.

Second Embodiment
Next, a second embodiment will be described. In the present embodiment, a feedback value obtained from a deviation ΔV between the target vehicle speed Vtrg and the actual vehicle speed Vr is obtained with respect to the one provided with the target acceleration generator 14 similar to that in the first embodiment described above. The increase / decrease tendency of the deviation ΔV is recognized and corrected by a gain set according to this tendency. In the following description, differences from the first embodiment described above will be mainly described, and a part of the description of common points will be omitted.

-Outline configuration of engine bench tester-
FIG. 3 shows a schematic configuration of a control block of the engine bench tester according to the present embodiment. As shown in FIG. 3, the engine bench tester according to the present embodiment includes an operation pattern generator 1 that outputs various operation conditions such as the target vehicle speed, which is the operation pattern, and a feedforward system (feedforward circuit) 2. And a feedback system (feedback circuit) 3 and an accelerator pedal opening calculation system for determining an accelerator pedal opening θ based on output values (target acceleration Atrg, corrected acceleration A2) from the feedforward system 2 and the feedback system 3 (Opening calculation system) 4 is provided. Each will be described below. The configuration of the operation pattern generator 1 is the same as that of the first embodiment described above, and a description thereof is omitted here.

(Feed forward system 2)
The feedforward system 2 receives the target acceleration Atrg signal transmitted from the target acceleration generator 14, and uses the target acceleration Atrg signal as an output signal from the feedforward system 2 and an output signal from the feedback system 3. Each is received and added to the acceleration adder 20 for output.

(Feedback system 3)
The feedback system 3 includes an engine speed detector (engine speed sensor) 31, a vehicle speed calculation unit 32, a vehicle speed comparator 33, a PID control unit 34, an acceleration correction value calculator 35, and a gain changer (gain setting means) 36. It has.

  The configurations of the engine speed detector 31, the vehicle speed calculation unit 32, and the vehicle speed comparator 33 are the same as those in the first embodiment described above.

  The PID controller 34 obtains a corrected vehicle speed value V1 corresponding to the deviation ΔV by performing PID (proportional / integral / derivative) control on the deviation ΔV calculated by the vehicle speed comparator 33.

  In the acceleration correction value calculator 35, the corrected vehicle speed value V1 obtained by the PID control unit 34 is divided by a predetermined time required for correcting the vehicle speed (required time for making the actual vehicle speed Vr coincide with the target vehicle speed Vtrg: Tconst). Thus, the basic correction acceleration A1 is calculated.

  The gain changer 36 obtains a gain Gv corresponding to the current change state of the actual vehicle speed with respect to the basic correction acceleration A1 calculated by the acceleration correction value calculator 35, and multiplies the basic correction acceleration A1 by this gain Gv. By doing so, the corrected acceleration A2 is determined. Hereinafter, the setting operation of the gain Gv in the gain changer 36 will be described.

  FIG. 4 shows an example of the temporal change of the vehicle speed, where α in the figure shows the target vehicle speed, that is, the change state of the target vehicle speed Vtrg output from the target vehicle speed generator 11. FIG. 4 shows a state where the target vehicle speed Vtrg is accelerated at a constant acceleration. Also, β and γ in the figure are actual vehicle speeds (vehicle speed Vr calculated by the vehicle speed calculation unit 32), and β is a deviation width (speed deviation: ΔV) of the actual vehicle speed Vr with respect to the target vehicle speed Vtrg as time elapses. Γ indicates that the divergence width of the actual vehicle speed Vr with respect to the target vehicle speed Vtrg (speed deviation: ΔV) is decreasing with time. That is, β represents a situation where the actual acceleration is smaller than the acceleration that is the change value of the target vehicle speed, and γ represents a situation where the actual acceleration is larger than the acceleration that is the change value of the target vehicle speed.

  The gain changer 36 discriminates both of them. In the former case (the situation where the speed deviation ΔV increases), the gain Gv is set to a large value of “1” or more, and the latter (the speed deviation ΔV decreases). In such a situation, the gain Gv is set to a small value of “1” or less. That is, the amount of change in the actual vehicle speed per unit time is detected, and whether the acceleration (actual acceleration) obtained thereby is larger or smaller than the acceleration in the change pattern of the target vehicle speed Vtrg is determined, and the actual acceleration is smaller. In this case, the gain Gv is set to a large value of “1” or more, and when the actual acceleration is larger, the gain Gv is set to a small value of “1” or less. In this case, the following arithmetic expression is used to calculate the gain Gv.

When speed deviation is enlarged: Gv = (1+ | a1-a | ÷ Aconst) (1)
When speed deviation is reduced: Gv = (1- | a2-a | ÷ Aconst) (2)
(Gv: gain, a: acceleration that is a change in the target vehicle speed (corresponding to the inclination of α in FIG. 4), a1: actual acceleration when the speed deviation is enlarged (corresponding to the inclination of the tangent of β in FIG. 4), a2: speed Actual acceleration at the time of deviation reduction (equivalent to the slope of the tangent of γ in FIG. 4), Aconst: constant)
According to these arithmetic expressions, when the speed deviation is enlarged, the gain (Gv) is set to a value in the range of 1 to 2 according to the magnitude of the deviation (acceleration deviation) between a and a1 (the acceleration deviation is On the other hand, when the speed deviation is reduced, the gain (Gv) is in the range of 0 to 1 depending on the magnitude of the deviation (acceleration deviation) between a and a2. (The gain Gv is also set to a smaller value as the acceleration deviation is smaller). That is, the gain Gv is set so that the corrected acceleration A2 is larger than the basic corrected acceleration A1 when the speed deviation is enlarged, while the gain Gv is set so that the corrected acceleration A2 is smaller than the basic corrected acceleration A1 when the speed deviation is reduced. Will be set. The numerical range described above can be arbitrarily set by changing the Aconst.

  The corrected acceleration A2 obtained by the above operation is output to the acceleration adder 20 and is added to the target acceleration Atrg output from the feedforward system 2 so as to be obtained as a target acceleration (added value) Atrg ′. It has become.

(Accelerator pedal opening calculation system 4)
The accelerator pedal opening calculation system 4 calculates an accelerator pedal opening θ based on the calculated target acceleration Atrg ′, and includes a vehicle inertia moment multiplication unit 41, a tire radius multiplication unit 45, a road resistance calculation unit. 42, a gear ratio multiplication unit 43, and an NT map 44 are provided. The vehicle inertia moment multiplication unit 41, the tire radius multiplication unit 45, the road resistance calculation unit 42, the gear ratio multiplication unit 43, and the NT map 44 have the same configuration as that of the first embodiment described above. A pedal opening θ is obtained.

  The accelerator pedal opening θ signal thus obtained is input to the pedal actuator 7 to be operated to a predetermined accelerator pedal opening θ so that the actual vehicle speed Vr can be brought close to the target vehicle speed Vtrg. ing.

  Since the accelerator pedal opening control operation as described above is performed, in this embodiment, the following effects can be obtained in addition to the effects in the first embodiment described above. First, in a situation where the speed deviation ΔV is increased, the gain is set as a large value (a value of 1 or more) and the corrected acceleration A2 is obtained as a large value, whereas in a situation where the speed deviation ΔV is reduced, the gain is a small value (1 or less). Therefore, the corrected acceleration A2 can be obtained with a small value, so that the actual vehicle speed can be made to follow the change pattern (vehicle speed change pattern) with high accuracy. Can be executed. As a result, frequent increase / decrease of the accelerator pedal operation amount (accelerator pedal depressing operation) can be eliminated, and an appropriate accelerator pedal operation amount can be obtained in the entire engine speed range. Driving reliability can be increased.

  In addition, the corrected acceleration A2 obtained by the feedback system 3 is added to the target acceleration Atrg from the feedforward system 2 before the accelerator pedal opening θ is determined by the accelerator pedal opening calculation system 4. Therefore, it is possible to reduce the time required for tuning the feedback gain (PID control gain), and even if the engine E to be tested is replaced, the simulation operation can be started without tuning the feedback gain. is there.

-Other embodiments-
In the embodiment described above, the case where an engine performance test or the like is performed while controlling the accelerator pedal opening degree in order to change the vehicle speed along a predetermined driving pattern has been described. The present invention is not limited to this, and can also be applied to an apparatus that controls the accelerator pedal opening in order to change the engine speed in accordance with a predetermined operation pattern (for example, Japanese Patent No. 2727229). Further, as a control target, it is also possible to set the throttle valve opening in place of the accelerator pedal opening. In other words, the present invention can be applied to a case in which the opening degree of the throttle valve provided in the engine intake system is directly adjusted by a throttle motor or the like.

  Furthermore, in the above-described embodiment, the case where the present invention is applied to an engine bench tester as a vehicle tester has been described. The present invention is not limited to this, and can be applied to a chassis dynamometer. In this case, instead of calculating the actual vehicle speed from the engine speed, gear ratio, or the like as in the above-described embodiment, the rotational speed of the tire can be directly sensed, and the sensed value can be used as the actual vehicle speed.

  Further, in the above embodiment, the simulation operation assuming a vehicle equipped with a manual transmission as a transmission has been described. The present invention is not limited to this, and can also be applied to a simulated operation assuming a vehicle equipped with an automatic transmission. In this case, regarding the calculation of the target torque Ttrg, a block having a transfer function corresponding to the torque converter is added to the control logic.

It is a figure which shows schematic structure of the control block of the engine bench tester which concerns on 1st Embodiment. It is a figure which shows the result of the experiment conducted in order to confirm the effect of 1st Embodiment. It is a figure which shows schematic structure of the control block of the engine bench tester which concerns on 2nd Embodiment. It shows an example of the temporal change in the vehicle speed. The change state of the target vehicle speed, the vehicle speed change state in which the divergence width of the actual vehicle speed with respect to the target vehicle speed increases with time, the actual vehicle speed with respect to the target vehicle speed with time It is a figure which respectively shows the vehicle speed change state which the deviation width | variety reduces. It is a figure which shows schematic structure of the control block of the conventional engine bench tester.

Explanation of symbols

14 Target acceleration generator (target acceleration storage means)
2 Feedforward system 20 Acceleration adders 21 and 41 Vehicle inertia moment multiplication units 24 and 44 NT map 3 Feedback system 34 PID control unit 35 Acceleration correction value calculator 36 Gain changer (gain setting means)
4. Accelerator pedal opening calculation system (opening calculation system)
6 Adder (addition means)
E Engine Vtrg Target vehicle speed Vr Calculated vehicle speed (actual vehicle speed)
ΔV Vehicle speed deviation Atrg Target acceleration A1 Basic correction acceleration A2 Correction acceleration Ftrg Target driving force Ttrg Target torque Gv Gain θa Basic accelerator pedal opening (feed forward control value, basic throttle opening)
θb Accelerator pedal opening correction value (feedback correction value, throttle opening correction value)
θ Accelerator pedal opening (throttle opening)

Claims (5)

A feedforward system for obtaining a “feedforward control value” by feedforward control, and a feedback system for obtaining a “feedback correction value” for bringing the actual vehicle speed closer to the target vehicle speed based on a deviation between the target vehicle speed and the actual vehicle speed. Alternatively, when performing a simulated engine operation, based on the value obtained by adding the “feedback correction value” obtained by the feedback system to the “feedforward control value” obtained by the feedforward system, In the automatic driving control device in the vehicle tester to determine "
A target acceleration storage means in which information on temporal changes in vehicle target acceleration corresponding to the simulated operation of the vehicle or engine is stored in advance;
The automatic driving control apparatus for a vehicle tester, wherein the feedforward system is configured to obtain a “feedforward control value” in response to a vehicle target acceleration signal from the target acceleration storage means. A feedforward system for obtaining a “feedforward control value” by feedforward control and a “feedback correction value” for bringing the actual engine speed closer to the target engine speed based on the deviation between the target engine speed and the actual engine speed. When performing a simulated operation of a vehicle or an engine, the “feedback correction value” obtained by the feedback system is added to the “feedforward control value” obtained by the feedforward system. In an automatic operation control apparatus in a vehicle tester that determines a “throttle opening” based on a value,
A target acceleration storage means in which information on temporal changes in engine speed target acceleration corresponding to the simulated operation of the vehicle or engine is stored;
2. The automatic operation control apparatus in a vehicle tester, wherein the feedforward system is configured to obtain a “feedforward control value” by receiving an engine speed target acceleration signal from the target acceleration storage means. In the automatic operation control apparatus in the vehicle tester according to claim 1,
The “feedforward control value” is the basic throttle opening (θa) obtained based on the vehicle target acceleration signal received from the target acceleration storage means,
The “feedback correction value” is a throttle opening correction value (θb) obtained based on a deviation (ΔV) between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr). Operation control device. Information on the temporal change in the vehicle target acceleration (Atrg) corresponding to the simulated operation of the vehicle or engine receives a vehicle target acceleration (Atrg) signal stored in advance from the target acceleration storage means (14). A vehicle inertia moment multiplier (21) that calculates a target driving force (Ftrg) by multiplying the acceleration (Atrg) by the vehicle inertia moment, and a target driving force (Ftrg) calculated by the vehicle inertia moment multiplier (21). A feedforward system (2) having an NT map (24) for obtaining a basic throttle opening (θa) from a target torque (Ttrg) calculated based on
A feedback system (3) having a PID control unit (34) for calculating a throttle opening correction value (θb) by performing PID control on a deviation (ΔV) between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr);
By adding the throttle opening correction value (θb) obtained by the feedback system (3) to the basic throttle opening (θa) obtained by the feedforward system (2), the throttle opening (θ) And an addition means (6) for determining the automatic driving control device in the vehicle tester. A feedforward system (2) to which target acceleration storage means (14) in which information on temporal changes in vehicle target acceleration (Atrg) corresponding to simulated operation of the vehicle or engine is stored in advance is connected;
A PID control unit (34) that calculates a corrected vehicle speed value (V1) by performing PID control on a deviation (ΔV) between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr), and the PID control unit (34). The acceleration correction value calculator (35) for calculating the basic correction acceleration (A1) by dividing the corrected vehicle speed value (V1) by the time (Tconst) required for correction of the vehicle speed, and the acceleration correction value calculator (35 A feedback system (3) having a gain setting means (36) for correcting the basic corrected acceleration (A1) calculated in (1) with a predetermined gain (Gv) to obtain the corrected acceleration (A2);
An acceleration adder (20) for adding the vehicle target acceleration (Atrg) from the feedforward system (2) and the corrected acceleration (A2) obtained by the feedback system (3) to obtain the target acceleration (Atrg '); The vehicle inertia moment multiplier (41) for calculating the target driving force (Ftrg) by multiplying the target acceleration (Atrg ') obtained by the acceleration adder (20) by the vehicle inertia moment, and the vehicle inertia moment Opening calculation having an NT map (44) for determining the throttle opening from the target torque (Ttrg) calculated based on the target driving force (Ftrg) calculated by the multiplication unit (41) and the current engine speed. System (4), and
The gain (Gv) for correcting the basic correction acceleration (A1) in the gain setting means (36) is variable, and the gain setting means (36) is a deviation between the target vehicle speed (Vtrg) and the actual vehicle speed (Vr). In the situation where this deviation increases, the correction acceleration (A2) is set to a gain obtained as a larger value than the basic correction acceleration (A1), while this deviation decreases. An automatic driving control device in a vehicle tester, characterized in that the corrected acceleration (A2) is set to a gain obtained as a value smaller than the basic corrected acceleration (A1) in the situation.

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