JP2019177859A - Vehicle speed control device - Google Patents

Abstract

To solve the risk of a gap between a driving operation by a driver and a pedal operation to be executed when the size of a feedback process value increases despite under a determination that the pedal operation is unnecessary, if an accelerator pedal operation amount and a brake pedal operation amount are acquired as the sum of a feedforward process value and a feedback process value respectively, in a vehicle speed control device which controls a vehicle so that a predetermined command speed that changes with time and a traveling speed coincide with each other.SOLUTION: If a feedforward process value is "0", it is determined that a pedal operation is unnecessary. In this case, if the relation between a command speed and a traveling speed satisfies a predetermined condition, the pedal operation is not to be executed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vehicle speed control device that controls a vehicle so that the traveling speed matches a predetermined command speed that changes with time.

  For example, the vehicle speed control device is used for measuring the fuel consumption of a vehicle. Therefore, vehicle control similar to the driving operation by the driver of the vehicle is required for the vehicle speed control device. One of the vehicle speed control devices of this type (hereinafter also referred to as “conventional device”) uses a value (feedforward operation) obtained from a target value (target accelerator operation amount) of an accelerator operation amount by a feedforward process. (Quantity) and the value obtained by the feedback process (feedback manipulated variable) (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 2007-155643

  For example, the feedforward operation amount is determined based on vehicle characteristics acquired (learned) in advance. The vehicle characteristics are constituted by various combinations of travel speed, pedal operation amounts (accelerator pedal and brake pedal), and vehicle acceleration. As a result of the vehicle being controlled based on the feedforward operation amount, if the difference between the traveling speed and the command speed increases, the feedback operation amount is determined so that the difference decreases.

  If it is determined that the pedal operation is unnecessary based on the vehicle characteristics, the feedforward operation amount is set to “0”. When it is determined that the pedal operation is unnecessary based on the vehicle characteristics, the driver generally does not perform the pedal operation. Therefore, unnecessary pedal operations should be avoided in such cases. However, even in such a case, the pedal operation may be performed based on the feedback operation amount.

  In other words, in the conventional apparatus, it has not been considered whether or not the pedal operation is determined to be unnecessary based on the vehicle characteristics when determining the feedback operation amount. Therefore, according to the conventional apparatus, there is a possibility that the pedal operation is executed in a situation where the driver does not perform the pedal operation.

  Accordingly, one of the objects of the present invention is to provide a vehicle speed control device capable of avoiding unnecessary pedal operation when it is determined that the pedal operation is unnecessary based on vehicle characteristics. is there.

  A vehicle speed control device (hereinafter also referred to as “device of the present invention”) for achieving the above object includes a vehicle speed acquisition unit, a target operation amount setting unit, a signal output unit, a reference operation amount acquisition unit, and a differential operation. A quantity acquisition unit is included (vehicle speed control device 50).

The vehicle speed acquisition unit
An accelerator operation amount (Ap) that is a value greater than or equal to “0” representing the operation amount of the accelerator pedal (21) and a brake operation amount (Bp) that is a value greater than or equal to “0” that represents the operation amount of the brake pedal (23). Accordingly, the traveling speed (Vs) of the vehicle (10) that controls the driving force and the braking force is acquired.

The target manipulated variable setting unit
The target accelerator operation amount (Atg) and the target brake operation amount (Btg) for making the travel speed coincide with a predetermined command speed (Vd) that changes with time, the target accelerator operation amount and the target brake operation amount. Is set to be “0”.

The signal output unit is
An accelerator operation amount signal (Sap) that is a signal representing the target accelerator operation amount and the target brake operation amount so that the driving force and braking force of the vehicle are controlled according to the target accelerator operation amount and the target brake operation amount. Is output as a brake operation amount signal (Sbp).

Furthermore, the reference operation amount acquisition unit
An accelerator pedal operation amount map (a pedal operation amount map in FIG. 7) that is a previously acquired relationship between the combination of the traveling speed and the accelerator operation amount and the acceleration (Ac) of the vehicle corresponding to the combination. In addition, a value obtained by applying the command speed and command acceleration (Ad) that is a change amount per unit time of the command speed is obtained as a reference accelerator operation amount (Aff), and the travel speed and the In the brake pedal operation amount map (pedal operation amount map in FIG. 7) which is a previously acquired relationship between the combination of brake operation amounts and the acceleration of the vehicle corresponding to the combination, the indicated speed and the A value obtained by applying the commanded acceleration is acquired as a reference brake operation amount (Bff).

The differential operation amount acquisition unit
The difference accelerator operation amount (Afb), which increases as the accelerator speed difference (ΔVa) obtained by subtracting the command speed from the travel speed, and the brake speed difference (ΔVb), obtained by subtracting the command speed from the travel speed. The difference brake operation amount (Bfb) that increases as the value increases.

Furthermore, the target manipulated variable setting unit
The process of acquiring the sum of the reference accelerator operation amount and the differential accelerator operation amount as the target accelerator operation amount, or the sum of the reference brake operation amount and the differential brake operation amount is acquired as the target brake operation amount. Execute the process.

In addition, the differential manipulation amount acquisition unit
When the reference accelerator operation amount is “0” (condition (FA1)) and the magnitude of the accelerator speed difference is equal to or less than a predetermined speed threshold value (Vth) (condition (FA2)), the difference accelerator operation amount is set. Set to “0”,
If the reference brake operation amount is “0” (condition (FB1)) and the magnitude of the brake speed difference is a negative value (condition (FB2)), the difference brake operation amount is set to “0”. To do.

  When it is determined that the accelerator operation is unnecessary based on the vehicle characteristics, the reference accelerator operation amount is “0”. In this case, if the magnitude of the difference between the traveling speed and the instruction speed is small, the accelerator operation is not executed.

  On the other hand, when it is determined that the brake operation is unnecessary based on the vehicle characteristics, the reference brake operation amount is “0”. In this case, if the traveling speed is lower than the instruction speed, the brake operation is not executed.

  Therefore, according to the device of the present invention, when it is determined that the pedal operation is unnecessary based on the vehicle characteristics, there is a high possibility that the unnecessary pedal operation can be avoided.

  In the above description, in order to help understanding of the present invention, names and / or symbols used in the embodiment are attached to the configuration of the invention corresponding to the embodiment described later in parentheses. However, each component of the present invention is not limited to the embodiment defined by the names and / or symbols. Other objects, other features and attendant advantages of the present invention will be readily understood from the description of the embodiments of the present invention described with reference to the following drawings.

It is the schematic which showed the vehicle (this vehicle) by which the vehicle speed control apparatus (this control device) which concerns on embodiment of this invention is mounted, and the chassis dynamometer by which this vehicle is installed. It is a block diagram showing the functional block implement | achieved when this support apparatus performs a vehicle speed control process. It is a block diagram showing the functional block of the accelerator operation amount calculating part of this control apparatus. It is a figure showing the relationship (map) of acceleration and jerk, and a judgment value. It is a figure showing the relationship (map) between a judgment value and a gain. It is a block diagram showing the functional block of the brake operation amount calculating part of this control apparatus. It is the figure which showed the pedal operation amount map referred in order to determine a reference accelerator operation amount and a reference brake operation amount based on instruction | command speed and instruction | command acceleration. It is a time chart showing the change of the vehicle speed at the time of execution of an accelerator acceleration test, a brake operation amount, and an accelerator operation amount. It is an enlarged view of a pedal operation amount map. 6 is a time chart showing changes in vehicle speed, brake operation amount, and accelerator operation amount when an accelerator deceleration test is executed. It is a time chart showing the change of the vehicle speed at the time of execution of a brake acceleration test, a brake operation amount, and an accelerator operation amount. 6 is a time chart showing changes in vehicle speed, brake operation amount, and accelerator operation amount during execution of a brake deceleration test. 6 is a time chart showing changes in an instruction speed, a vehicle speed, a reference accelerator operation amount, a basic accelerator operation amount, a reference accelerator operation amount, and a basic brake operation amount when a brake feedback stop condition is satisfied. 6 is a time chart showing changes in an instruction speed, a vehicle speed, a reference accelerator operation amount, a basic accelerator operation amount, a reference accelerator operation amount, and a basic brake operation amount when an accelerator feedback stop condition is satisfied. It is a figure showing the judgment value and gain corresponding to each driving state of this vehicle.

  Hereinafter, a vehicle speed control device (hereinafter also referred to as “the present control device”) according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a vehicle 10, a chassis dynamometer 30, a vehicle speed control device 50, and a pedal actuator 71. This control device is applied to the vehicle speed control device 50.

  The vehicle 10 includes an accelerator pedal 21, an accelerator pedal operation amount sensor 22, a brake pedal 23, driving wheels 24 and steering wheels 25.

  The accelerator pedal operation amount sensor 22 acquires an accelerator operation amount Ap that is an operation amount (depression amount) of the accelerator pedal 21, and an accelerator operation amount signal Sap that is a voltage signal representing the accelerator operation amount Ap is controlled by a control device ( (Not shown). When the accelerator pedal 21 is not operated, the accelerator operation amount Ap is “0”. The accelerator operation amount Ap increases as the operation amount of the accelerator pedal 21 increases.

  The voltage of the accelerator operation amount signal Sap is proportional to the accelerator operation amount Ap. In other words, when the accelerator operation amount Ap is constant, the accelerator operation amount signal Sap is a DC signal whose voltage does not change.

  The control device of the vehicle 10 determines the torque (driving force) to be generated in the driving wheels 24 based on the accelerator operation amount Ap, the vehicle speed Vs that is the traveling speed of the vehicle 10, and the like.

  When a depressing force is applied to the brake pedal 23, that is, when the brake operation amount Bp, which is the operation amount of the brake pedal 23, increases, the friction brake device (not shown) of the vehicle 10 is activated, thereby driving the drive wheel 24 and the steering wheel. A braking force is generated in the wheel 25. When the brake pedal 23 is not operated, the brake operation amount Bp is “0”. As the operation amount of the brake pedal 23 increases, the brake operation amount Bp increases.

  The vehicle 10 is installed on the chassis dynamometer 30. The chassis dynamometer 30 includes a load roller 41 and a control panel 42. The load roller 41 rotates according to the rotation of the drive wheel 24. The road roller 41 generates a rotational resistance corresponding to a traveling resistance when the vehicle 10 actually travels on the road in response to an instruction from the control panel 42.

  The control panel 42 acquires the vehicle speed Vs based on the rotation speed of the road roller 41 and transmits a vehicle speed signal Svs, which is a voltage signal representing the vehicle speed Vs, to the vehicle speed control device 50. The voltage of the vehicle speed signal Svs is proportional to the vehicle speed Vs.

  The vehicle speed control device 50 includes a DSP (digital signal processor) 61, an ADC (analog / digital converter) 62, and a DAC (digital / analog converter) 63. The DSP 61 of the vehicle speed control device 50 includes a program memory and a data memory (both not shown).

  The vehicle speed control device 50 transmits a brake operation amount signal Sbp which is a voltage signal representing the brake operation amount Bp to the pedal actuator 71. The pedal actuator 71 pushes the brake pedal 23 in accordance with the brake operation amount signal Sbp, thereby controlling the brake operation amount Bp. As the voltage of the brake operation amount signal Sbp increases, the brake operation amount Bp increases.

  In addition, the vehicle speed control device 50 is connected to the accelerator pedal operation amount sensor 22. The vehicle speed control device 50 can transmit an accelerator operation amount signal Sap to the control device of the vehicle 10 via the accelerator pedal operation amount sensor 22.

  Therefore, even if there is no driver who operates the accelerator pedal 21 and the brake pedal 23, the vehicle speed control device 50 transmits the accelerator operation amount signal Sap and the brake operation amount signal Sbp to thereby increase the driving force and the braking force of the vehicle 10. Can be controlled.

  The vehicle speed control device 50 executes a vehicle speed control process according to a program stored in the program memory of the DSP 61. The vehicle speed control process is a process of controlling the accelerator operation amount signal Sap transmitted to the pedal actuator 71 and the vehicle 10 so that the vehicle speed Vs matches the instruction speed Vd that changes with time.

  When the vehicle speed control process is executed, the vehicle speed control device 50 sets the target accelerator operation amount Atg and the target brake operation amount Btg at predetermined time intervals. The DAC 63 generates (outputs) an accelerator operation amount signal Sap and a brake operation amount signal Sbp according to the target accelerator operation amount Atg and the target brake operation amount Btg.

  The command speed Vd is determined based on, for example, the JC08 mode fuel consumption test and the WLTP fuel consumption test. The command speed Vd corresponding to each elapsed time Te, which is the time that has elapsed since the start of the vehicle speed control process, is stored in the data memory of the vehicle speed control device 50. Hereinafter, the amount of change per unit time of the command speed Vd is also referred to as command acceleration Ad.

  Hereinafter, the instruction speed Vd corresponding to the elapsed time Te is also expressed as the instruction speed Vd (Te). In addition, the commanded acceleration Ad at the elapsed time Te is also expressed as the commanded acceleration Ad (Te). That is, the elapsed time from the start of the vehicle speed control process for the command speed Vd and the command acceleration Ad may be given in parentheses.

  FIG. 2 is a configuration diagram showing functional blocks realized by the DSP 61 of the vehicle speed control device 50 when the vehicle speed control process is executed. The functional blocks at the time of execution of the vehicle speed control process include a filter unit 81, a first-out unit 82, an accelerator operation recognition unit 83, a brake operation recognition unit 84, an accelerator operation amount calculation unit 85, a brake operation amount calculation unit 86, an operation selection unit 87, and An operation amount output unit 88 is included.

  The filter unit 81 operates as a low pass filter. The filter unit 81 removes a noise component included in the vehicle speed signal Svs received from the chassis dynamometer 30. The filter unit 81 outputs the vehicle speed Vs acquired by removing the noise component from the vehicle speed signal Svs to the accelerator operation recognition unit 83, the brake operation recognition unit 84, the accelerator operation amount calculation unit 85, and the brake operation amount calculation unit 86. .

  The first-out unit 82 acquires first-out times corresponding to the accelerator operation recognition unit 83, the brake operation recognition unit 84, the accelerator operation amount calculation unit 85, and the brake operation amount calculation unit 86, respectively. The advance time is set in order to correct the control delay times of the accelerator operation recognition unit 83, the brake operation recognition unit 84, the accelerator operation amount calculation unit 85, and the brake operation amount calculation unit 86.

  The advance portion 82 outputs the reference accelerator advance time Taf to the accelerator operation recognition portion 83 and the accelerator operation amount calculation portion 85. The first-out unit 82 outputs the reference brake first-out time Tbf to the brake operation recognition unit 84 and the brake operation amount calculation unit 86.

  The advance portion 82 outputs the differential accelerator advance time Tab to the accelerator operation amount calculation portion 85. First-out unit 82 outputs differential brake first-out time Tbb to brake operation amount calculation unit 86.

  The accelerator operation recognition unit 83 acquires the sum of the elapsed time Te and the reference accelerator advance time Taf as the reference accelerator elapsed time Tafe (that is, Tafe = Te + Taf). In addition, the accelerator operation recognizing unit 83 acquires the reference accelerator operation amount Aff based on the instruction speed Vd (Tafe) and the instruction acceleration Ad (Tafe) corresponding to the reference accelerator elapsed time Tafe, and the reference accelerator operation amount Aff is obtained. It outputs to the operation selection part 87 as the recognition accelerator operation amount Ade.

  The reference accelerator operation amount Aff is an accelerator operation amount Ap that realizes a combination of the corresponding vehicle speed Vs and acceleration Ac. That is, when the vehicle speed Vs is equal to the commanded speed Vd (Tafe) and the accelerator operation amount Ap is equal to the acquired reference accelerator operation amount Aff (cognitive accelerator operation amount Ade), the acceleration Ac is equal to the commanded acceleration Ad (Tafe). Become.

  When the combination of the vehicle speed Vs and the acceleration Ac is realized by the accelerator operation, the reference accelerator operation amount Aff becomes a positive value. On the other hand, when the combination of the vehicle speed Vs and the acceleration Ac is realized by a brake operation, the reference accelerator operation amount Aff is “0”. A method for obtaining the reference accelerator operation amount Aff will be described later.

  The brake operation recognition unit 84 acquires the sum of the elapsed time Te and the reference brake advance time Tbf as the reference brake elapsed time Tbfe (that is, Tbfe = Te + Tbf). In addition, the accelerator operation recognition unit 83 acquires the reference brake operation amount Bff based on the instruction speed Vd (Tbfe) and the instruction acceleration Ad (Tbfe) corresponding to the reference brake elapsed time Tbfe, and uses the reference brake operation amount Bff. It outputs to the operation selection part 87 as recognition brake operation amount Bde.

  The reference brake operation amount Bff is a brake operation amount Bp that realizes a combination of the corresponding vehicle speed Vs and acceleration Ac. That is, when the vehicle speed Vs is equal to the command speed Vd (Tbfe) and the brake operation amount Bp is equal to the acquired reference brake operation amount Bff (that is, the recognized brake operation amount Bde), the acceleration Ac is the command acceleration Bd (Tbfe). Is equal to

  When the combination of the vehicle speed Vs and the acceleration Ac is realized by a brake operation, the reference brake operation amount Bff becomes a positive value. On the other hand, when the combination of the vehicle speed Vs and the acceleration Ac is realized by the accelerator operation, the reference brake operation amount Bff is “0”. A method for obtaining the reference brake operation amount Bff will be described later.

  The accelerator operation amount calculation unit 85 acquires the reference accelerator operation amount Aff in the same manner as the accelerator operation recognition unit 83. In addition, the accelerator operation amount calculation unit 85 acquires a differential accelerator operation amount Afb. Further, the accelerator operation amount calculation unit 85 outputs either the sum of the reference accelerator operation amount Aff and the differential accelerator operation amount Afb or the reference accelerator operation amount Aff to the operation selection unit 87 as the required accelerator operation amount Ana. .

  This will be described more specifically with reference to FIG. FIG. 3 is a configuration diagram illustrating functional blocks included in the accelerator operation amount calculation unit 85. The accelerator operation amount calculation unit 85 includes a feedforward calculation unit 90a, a gain determination unit 91a, a reference governor calculation unit 92a, a feedback calculation unit 93a, and an output value selection unit 94a. In addition, the accelerator operation amount calculation unit 85 includes a differentiator 95a, a differentiator 96a, a differentiator 97a, a differentiator 98a, and an adder 99a.

  The differentiator 95a acquires a commanded acceleration Ad (Tafe), which is a change amount per unit time, of the commanded speed Vd (Tafe) corresponding to the reference accelerator elapsed time Taf, and feeds the commanded acceleration Ad (Tafe) into the feedforward calculation unit 90a. Output to.

  The feedforward calculation unit 90a acquires the reference accelerator operation amount Aff based on the input command speed Vd (Tafe) and command acceleration Ad (Tafe), and uses the reference accelerator operation amount Aff as an output value selection unit 94a and an adder 99a. Output to.

  The differentiator 96a acquires an instruction acceleration Ad (Te) that is a change amount per unit time of the instruction speed Vd (Te), and outputs the instruction acceleration Ad (Te) to the gain determination unit 91a and the differentiator 97a.

  The differentiator 97a acquires the jerk Jk (Te) that is the amount of change per unit time of the commanded acceleration Ad (Te), and outputs the jerk Jk (Te) to the gain determination unit 91a.

  The gain determination unit 91a acquires the gain Ga based on the determination value Dv, and outputs the gain Ga to the reference governor calculation unit 92a. More specifically, the gain determination unit 91a obtains the determination value Dv by applying the combination of the commanded acceleration Ad (Te) and the jerk Jk (Te) to the relationship (determination value map) shown in FIG. To do.

  In application to the determination value map of FIG. 4, the acceleration Ac is classified into either “0” or “other than 0 (positive value or negative value)”. On the other hand, when applied to the judgment value map, the jerk Jk is classified into one of “0”, “small”, “medium”, and “large”.

  When the size of the jerk Jk is greater than “0” and equal to or less than a predetermined first jerk threshold Jth1, the jerk Jk is classified as “small”. When the size of the jerk Jk is larger than the first jerk threshold Jth1 and not more than the predetermined second jerk threshold Jth2, the jerk Jk is classified as “medium”. When the size of the jerk Jk is larger than the second jerk threshold Jth2, the jerk Jk is classified as “large”.

  When the determination value Dv is acquired, the gain determination unit 91a acquires the gain Ga by applying the determination value Dv to the relationship (gain map) shown in FIG.

  The subtractor 98a acquires an accelerator speed difference ΔVa that is a difference between the vehicle speed Vs and the command speed Vd (Te) corresponding to the elapsed time Te (that is, ΔVa = Vs−Vd (Te)), and the accelerator speed difference. ΔVa is output to the reference governor calculation unit 92a and the output value selection unit 94a.

  The reference governor calculation unit 92a obtains a corrected accelerator speed difference ΔVam that is the product of the gain Ga and the accelerator speed difference ΔVa (that is, ΔVam = Ga × ΔVa), and sends the corrected accelerator speed difference ΔVam to the feedback calculation unit 93a. Output

  The feedback calculator 93a acquires the basic accelerator operation amount Afp based on the corrected accelerator speed difference ΔVam, and outputs the basic accelerator operation amount Afp to the output value selection unit 94a. The feedback calculation unit 93a sets the basic accelerator operation amount Afp to a larger value as the corrected accelerator speed difference ΔVam is smaller.

  The output value selection unit 94a outputs “0” to the adder 99a as the differential accelerator operation amount Afb if a predetermined accelerator feedback stop condition is satisfied. On the other hand, if the accelerator feedback stop condition is not satisfied, the output value selection unit 94a outputs a value equal to the basic accelerator operation amount Afp to the adder 99a as the difference accelerator operation amount Afb.

The accelerator feedback stop condition is a condition that is satisfied when the following condition (FA1) and condition (FA2) are both satisfied.
Condition (FA1): The reference accelerator operation amount Aff acquired by the feedforward calculation unit 90a is “0” (that is, Aff = 0).
Condition (FA2): The accelerator speed difference ΔVa is smaller than a predetermined speed threshold value Vth (that is, | ΔVa | <Vth).

  The adder 99a outputs the sum of the reference accelerator operation amount Aff and the differential accelerator operation amount Afb as the required accelerator operation amount Ana.

  The brake operation amount calculation unit 86 acquires the reference brake operation amount Bff in the same manner as the brake operation recognition unit 84. In addition, the brake operation amount calculation unit 86 acquires the differential brake operation amount Bfb. Further, the brake operation amount calculation unit 86 outputs either the sum of the reference brake operation amount Bff and the differential brake operation amount Bfb and the reference brake operation amount Bff to the operation selection unit 87 as the required brake operation amount Bna. .

  This will be described more specifically with reference to FIG. FIG. 6 is a configuration diagram illustrating functional blocks included in the brake operation amount calculation unit 86. The brake operation amount calculation unit 86 includes a feedforward calculation unit 90b, a gain determination unit 91b, a reference governor calculation unit 92b, a feedback calculation unit 93b, and an output value selection unit 94b. In addition, the brake operation amount calculation unit 86 includes a differentiator 95b, a differentiator 96b, a differentiator 97b, a differentiator 98b, and an adder 99b.

  The differentiator 95b acquires a commanded acceleration Ad (Tbfe) that is a change amount per unit time of the commanded speed Vd (Tbfe) corresponding to the reference brake elapsed time Tbfe, and feeds the commanded acceleration Ad (Tbfe) to the feedforward calculating unit 90b. Output to.

  The feedforward calculation unit 90b acquires the reference brake operation amount Bff based on the input command speed Vd (Tbfe) and command acceleration Ad (Tbfe), and outputs the reference brake operation amount Bff to the output value selection unit 94b and the adder 99b. Output to.

  The differentiator 96a is a change amount per unit time of the command speed Vd (Tbbe) corresponding to the brake operation elapsed time Tbb (that is, Tbbe = Te + Tbb) which is the sum of the elapsed time Te and the difference brake advance time Tbb. The commanded acceleration Ad (Tbbe) is acquired, and the commanded acceleration Ad (Tbbe) is output to the gain determining unit 91b and the differentiator 97b.

  The differentiator 97b acquires the jerk Jk (Tbbe) that is the amount of change per unit time of the commanded acceleration Ad (Tbbe), and outputs the jerk Jk (Tbbe) to the gain determination unit 91b.

  The gain determination unit 91b acquires the gain Ga based on the determination value Dv, and outputs the gain Ga to the reference governor calculation unit 92b. That is, the gain determination unit 91b obtains the determination value Dv by applying the combination of the commanded acceleration Ad (Tbbe) and the jerk Jk (Tbbe) to the determination value map of FIG. Furthermore, the gain determination unit 91b acquires the gain Ga by applying the determination value Dv to the gain map of FIG.

  The subtractor 98b obtains a brake speed difference ΔVb that is a difference between the vehicle speed Vs and the command speed Vd (Te) corresponding to the elapsed time Te (that is, ΔVb = Vs−Vd (Te)), and the brake speed difference. ΔVb is output to the reference governor calculation unit 92b and the output value selection unit 94b.

  The reference governor calculation unit 92b acquires a corrected brake speed difference ΔVbm that is a product of the gain Ga and the brake speed difference ΔVb (that is, ΔVbm = Ga × ΔVb), and sends the corrected brake speed difference ΔVbm to the feedback calculation unit 93b. Output

  The feedback calculation unit 93b acquires the basic brake operation amount Bfp based on the corrected brake speed difference ΔVbm, and outputs the basic brake operation amount Bfp to the output value selection unit 94b. The feedback calculation unit 93b sets the basic brake operation amount Bfp to a larger value as the corrected brake speed difference ΔVbm is larger.

  If the predetermined brake feedback stop condition is satisfied, the output value selection unit 94b outputs “0” to the adder 99b as the differential brake operation amount Bfb. On the other hand, if the brake feedback stop condition is not satisfied, the output value selection unit 94a outputs a value equal to the basic brake operation amount Bfp to the adder 99b as the difference brake operation amount Bfb.

The brake feedback stop condition is a condition that is satisfied when both of the following conditions (FB1) and (FB2) are satisfied.
Condition (FB1): The reference brake operation amount Bff acquired by the feedforward calculation unit 90b is “0” (that is, Bff = 0).
Condition (FB2): The brake speed difference ΔVb is a negative value (that is, ΔVb = Vs−Vd <0).

  The adder 99b outputs the sum of the reference brake operation amount Bff and the difference brake operation amount Bfb as the required brake operation amount Bna.

  The operation selection unit 87 selects either an operation on the accelerator pedal 21 (accelerator operation) or an operation on the brake pedal 23 (brake operation) as an operation to be executed. Specifically, if the reference accelerator operation amount Aff becomes “0” when the accelerator operation has been selected so far, the operation selection unit 87 newly selects a brake operation. On the other hand, when the reference brake operation amount Bff becomes “0” when the brake operation has been selected so far, the operation selection unit 87 newly selects the accelerator operation.

  When the accelerator operation is selected, the operation selection unit 87 outputs the required accelerator operation amount Ana input from the accelerator operation amount calculation unit 85 to the operation amount output unit 88. On the other hand, the operation selection unit 87 outputs the necessary brake operation amount Bna input from the brake operation amount calculation unit 86 to the operation amount output unit 88 when the brake operation is selected.

  The operation amount output unit 88 obtains the target accelerator operation amount Atg and the target brake operation amount Btg based on the input value from the operation selection unit 87 (that is, one of the necessary accelerator operation amount Ana and the required brake operation amount Bna). Set. The operation amount output unit 88 outputs the set target accelerator operation amount Atg and target brake operation amount Btg to the DAC 63.

  When the input value from the operation selector 87 is the required accelerator operation amount Ana, the operation amount output unit 88 sets the target accelerator operation amount Atg to a value equal to the required accelerator operation amount Ana, while the target brake operation amount Btg is set. Set to “0”. Similarly, when the input value from the operation selection unit 87 is the required brake operation amount Bna, the operation amount output unit 88 sets the target brake operation amount Btg to a value equal to the required brake operation amount Bna, while the target accelerator operation amount The amount Atg is set to “0”.

  In addition, the operation amount output unit 88 performs simultaneous operation prohibition processing and rate limiter processing on the input value from the operation selection unit 87. The simultaneous operation prohibition process and the rate limiter process will be described by taking as an example a case where the input value from the operation selection unit 87 is the required accelerator operation amount Ana. Since these processes when the input value from the operation selection unit 87 is the required brake operation amount Bna are the same as those when the input value is the required accelerator operation amount Ana, description thereof will be omitted.

  The simultaneous operation prohibition process is executed in order to avoid switching between the accelerator operation and the brake operation in a short time. In general, when the driver drives the vehicle, a “step change” occurs in which a state in which one of the accelerator operation and the brake operation is performed is changed to a state in which the other one of the accelerator operation and the brake operation is performed. A certain amount of time is required when the driver makes a step change.

  Therefore, the operation amount output unit 88 sets the target accelerator operation amount Atg to “the target accelerator operation amount Atg” until a predetermined switching time Ti elapses after the input value from the operation selection unit 87 is switched from the necessary brake operation amount Bna to the necessary accelerator operation amount Ana. Set to “0”. The switching time Ti is set to a time required for a general driver of the vehicle 10 to switch between the accelerator pedal 21 and the brake pedal 23.

  The rate limiter process is executed to avoid sudden changes in the accelerator operation amount Ap and the brake operation amount Bp. In general, the driver of the vehicle does not change the accelerator operation amount Ap and the brake operation amount Bp abruptly in order to avoid sudden acceleration and deceleration (that is, a sudden change in the vehicle speed Vs).

  Therefore, the operation amount output unit 88 includes the required accelerator operation amount Ana newly input from the operation selection unit 87, the previous target accelerator operation amount Atgp that is the target accelerator operation amount Atg output last time by the operation amount output unit 88, and Is set to a predetermined accelerator operation change amount limit Apth or less. The difference between the required accelerator operation amount Ana newly input from the operation selection unit 87 and the previous target accelerator operation amount Atg is also referred to as an accelerator operation amount difference ΔAp (that is, ΔAp = Ana−Atgp).

  If the accelerator operation amount difference ΔAp is larger than the accelerator operation change amount limit Apth (that is, ΔAp> Apth), the operation selecting unit 87 sets the target accelerator operation amount Atg to “the previous target accelerator operation amount Atgp to the accelerator operation change amount limit Apth. Is set to a value obtained by adding (i.e. Atg ← Atgp + Apth).

  On the other hand, if the accelerator operation amount difference ΔAp is smaller than “a value obtained by multiplying the accelerator operation change amount limit Apth by“ −1 ”” (that is, ΔAp <−Apth), the operation selection unit 87 determines the target accelerator operation amount. Atg is set to “a value obtained by subtracting the accelerator operation change amount limit Apth from the previous target accelerator operation amount Atgp” (that is, Atg ← Atgp−Apth).

  When the above-described target accelerator operation amount Atg is not set by the simultaneous operation prohibition process and the rate limiter process, the operation amount output unit 88 sets the target accelerator operation amount Atg to a value equal to the required accelerator operation amount Ana. .

(Pedal operation amount map)
Next, a method for obtaining the reference accelerator operation amount Aff and the reference brake operation amount Bff will be described. The reference accelerator operation amount Aff and the reference brake operation amount Bff are obtained by applying the instruction speed Vd and the instruction acceleration Ad to the pedal operation amount map shown in FIG.

  Hereinafter, the combination of the command speed Vd and the command acceleration Ad is also referred to as “command operation state”. For example, the accelerator operation recognition unit 83 applies a combination of the instruction speed Vd (Tafe) and the instruction acceleration Ad (Tafe) to the pedal operation amount map as an instruction driving state.

  When the command operation state corresponds to the one-dot chain line Laa1 or the broken line Lad1 in FIG. 7, the reference accelerator operation amount Aff becomes the first accelerator operation amount Ap1. When the command operation state corresponds to the one-dot chain line Laa2 or the broken line Lad2, the reference accelerator operation amount Aff becomes the second accelerator operation amount Ap2. When the command operation state corresponds to the one-dot chain line Laa3 or the broken line Lad3, the reference accelerator operation amount Aff becomes the third accelerator operation amount Ap3.

  When the command operation state corresponds to the one-dot chain line Laa4 or the broken line Lad4, the reference accelerator operation amount Aff becomes the fourth accelerator operation amount Ap4. When the command operation state corresponds to the one-dot chain line Laa5, the reference accelerator operation amount Aff becomes the fifth accelerator operation amount Ap5. When the command operation state corresponds to the one-dot chain line Laa6, the reference accelerator operation amount Aff becomes the sixth accelerator operation amount Ap6.

  The first accelerator operation amount Ap1 is “0”. In addition, the first accelerator operation amount Ap1, the second accelerator operation amount Ap2, the third accelerator operation amount Ap3, the fourth accelerator operation amount Ap4, the fifth accelerator operation amount Ap5, and the sixth accelerator operation amount Ap6 increase in this order. (That is, 0 = Ap1 <Ap2 <Ap3 <Ap4 <Ap5 <Ap6).

  When the command operation state corresponds to the solid line Lba1 or the two-dot chain line Lbd1, the reference brake operation amount Bff is the first brake operation amount Bp1. When the command operation state corresponds to the solid line Lba2 or the two-dot chain line Lbd2, the reference brake operation amount Bff becomes the second brake operation amount Bp2.

  When the command operation state corresponds to the two-dot chain line Lbd3, the reference brake operation amount Bff is the third brake operation amount Bp3. When the command operation state corresponds to the two-dot chain line Lbd4, the reference brake operation amount Bff becomes the fourth brake operation amount Bp4. When the command operation state corresponds to the two-dot chain line Lbd5, the reference brake operation amount Bff becomes the fifth brake operation amount Bp5.

  The first brake operation amount Bp1 is a positive value. In addition, the first brake operation amount Bp1, the second brake operation amount Bp2, the third brake operation amount Bp3, the fourth brake operation amount Bp4, and the fifth brake operation amount Bp5 increase in this order (that is, 0 <Bp1 < Bp2 <Bp3 <Bp4 <Bp5).

  When the reference accelerator operation amount Aff acquired by applying the command operation state to the pedal operation amount map is a positive value, the reference brake operation amount Bff is “0”. On the other hand, when the reference brake operation amount Bff acquired by applying the commanded driving state to the pedal operation amount map is a positive value, the reference accelerator operation amount Aff is “0”.

  When the commanded acceleration Ad is a positive value and the reference accelerator operation amount Aff is a positive value, the commanded driving state is realized by the accelerator operation. That is, when the vehicle speed Vs is equal to the indicated speed Vd and the accelerator operation amount Ap is equal to the reference accelerator operation amount Aff, the acceleration Ac (in this case, the acceleration Ac is a positive value) that is a change amount per unit time. ) Is equal to the commanded acceleration Ad. The driving operation that increases the vehicle speed Vs by the accelerator operation (that is, sets the acceleration Ac to a positive value) is hereinafter also referred to as “accelerator acceleration”.

  On the other hand, even if the commanded acceleration Ad is a negative value, if the reference accelerator operation amount Aff is a positive value, the commanded driving state is realized by the accelerator operation (ie, accelerator deceleration). When the accelerator is decelerated, so-called engine braking is used.

  When the commanded acceleration Ad is a positive value and the reference brake operation amount Bff is a positive value, the commanded driving state is realized by a brake operation. Hereinafter, the driving operation for increasing the vehicle speed Vs by the brake operation is also referred to as “brake acceleration”. On the other hand, when the commanded acceleration Ad is a negative value and the reference brake operation amount Bff is a positive value, the commanded driving state is realized by a brake operation (that is, brake deceleration).

  Next, a method for generating a pedal operation amount map will be described. The pedal operation amount map of FIG. 7 shows vehicle characteristics of the vehicle 10 (specifically, acceleration Ac corresponding to each combination of the vehicle speed Vs and the accelerator operation amount Ap, and each combination of the vehicle speed Vs and the brake operation amount Bp). Represents the acceleration Ac) corresponding to. The vehicle characteristics of the vehicle 10 are acquired (learned) by experiments.

(1) Acceleration Acceleration An acceleration test performed to acquire vehicle characteristics (acceleration acceleration characteristics) related to acceleration of the vehicle 10 will be described.

  An example of changes with respect to time t of the accelerator operation amount Ap, the brake operation amount Bp, and the vehicle speed Vs when the accelerator acceleration test is executed is shown in the time chart of FIG. In this example, the accelerator acceleration characteristic in the vehicle 10 when the accelerator operation amount Ap is the third accelerator operation amount Ap3 is acquired.

  A curve Lv1 in FIG. 8 represents a change in the vehicle speed Vs. A broken line Lb1 represents a change in the brake operation amount Bp. A broken line La1 represents a change in the accelerator operation amount Ap.

  As understood from the curve Lv1, the vehicle speed Vs is “0” (that is, the vehicle 10 is stopped) until the time t0. At this time, the accelerator operation amount Ap is “0”, and the brake operation amount Bp is equal to the predetermined stop brake operation amount Bpp. The stop brake operation amount Bpp is set to a brake operation amount Bp sufficient to keep the vehicle 10 in a stopped state.

  When the brake operation amount Bp changes from the stop brake operation amount Bpp to “0” at time t0, the vehicle speed Vs starts to increase. That is, the vehicle 10 starts traveling due to a creep phenomenon. Thereafter, at time t1 when the switching time Ti has elapsed from time t0 (that is, t1 = t0 + Ti), the accelerator operation amount Ap changes from “0” to the third accelerator operation amount Ap3.

  As a result of the increase in the accelerator operation amount Ap, the acceleration Ac increases as compared to a state in which the accelerator operation amount Ap is “0”. Thereafter, the acceleration Ac gradually decreases. At time t2a, the vehicle speed Vs reaches the speed Vs1, and the acceleration Ac becomes substantially “0”.

  As a result of the accelerator acceleration test, the relationship between the vehicle speed Vs and the acceleration Ac in acceleration when the accelerator operation amount Ap is the third accelerator operation amount Ap3 is acquired based on the curve Lv1. That is, various combinations of the vehicle speed Vs represented by “a certain point” on the curve Lv1 and the acceleration Ac represented by the inclination of the curve Lv1 at “the point” are acquired.

  FIG. 9 is an enlarged view of the left half of the pedal operation amount map shown in FIG. A combination of the vehicle speed Vs and the acceleration Ac acquired as a result of the accelerator acceleration test when the accelerator operation amount Ap is the third accelerator operation amount Ap3 is represented by a solid line Laa3a and a broken line Laa3b in FIG. The curve representing the accelerator acceleration characteristic acquired by the accelerator acceleration test (in this case, the curve represented by the solid line Laa3a and the broken line Laa3b) is hereinafter also referred to as an “accelerator acceleration characteristic curve”.

  On the other hand, the alternate long and short dash line Laa3 in FIG. 7 is the same as the curve obtained by connecting the solid line Laa3a and the broken line Laa3c in FIG. By correcting a part of the accelerator acceleration characteristic curve (in this case, by obtaining a broken line Laa3c instead of the broken line Laa3b), a curve (in this case, a one-dot chain line Laa3) applied to the pedal operation amount map is obtained. Hereinafter, the processing is also referred to as “acceleration acceleration characteristic correction processing”.

  The accelerator acceleration characteristic correction process will be described. As understood from the solid line Laa3a and the broken line Laa3b, if the accelerator operation amount Ap is constant, the acceleration Ac increases as the vehicle speed Vs decreases, and then decreases. The broken line Laa3c is acquired so that the acceleration Ac continues to increase without decreasing even if the vehicle speed Vs decreases.

  For the accelerator operation amount Ap different from the third accelerator operation amount Ap3, the accelerator acceleration characteristic is acquired by the same accelerator acceleration test.

  Similarly to the case where the accelerator operation amount Ap is the third accelerator operation amount Ap3, the accelerator acceleration characteristic curve corresponding to the first accelerator operation amount Ap1 is represented by a solid line Laa1a and a broken line Laa1b. A broken line Laa1c is obtained by the accelerator acceleration characteristic correction processing for the accelerator acceleration characteristic curve. The one-dot chain line Laa1 is equal to a curve obtained by connecting the solid line Laa1a and the broken line Laa1c.

  The accelerator acceleration characteristic curve corresponding to the second accelerator operation amount Ap2 is represented by a solid line Laa2a and a broken line Laa2b. A broken line Laa2c is obtained by the accelerator acceleration characteristic correction process for the accelerator acceleration characteristic curve. The one-dot chain line Laa2 is equal to a curve obtained by connecting the solid line Laa2a and the broken line Laa2c.

  The accelerator acceleration characteristic curve corresponding to the fourth accelerator operation amount Ap4 is represented by a solid line Laa4a and a broken line Laa4b. A broken line Laa4c is obtained by the accelerator acceleration characteristic correction process for the accelerator acceleration characteristic curve. The alternate long and short dash line Laa4 is equal to a curve obtained by connecting the solid line Laa4a and the broken line Laa4c.

  The accelerator acceleration characteristic curve corresponding to the fifth accelerator operation amount Ap5 is represented by a solid line Laa5a and a broken line Laa5b. A broken line Laa5c is obtained by the accelerator acceleration characteristic correction process for the accelerator acceleration characteristic curve. The alternate long and short dash line Laa5 is equal to a curve obtained by connecting the solid line Laa5a and the broken line Laa5c.

  The accelerator acceleration characteristic curve corresponding to the sixth accelerator operation amount Ap6 is represented by a solid line Laa6a and a broken line Laa6b. A broken line Laa6c is obtained by the accelerator acceleration characteristic correction process for the accelerator acceleration characteristic curve. The alternate long and short dash line Laa6 is equal to a curve obtained by connecting the solid line Laa6a and the broken line Laa6c.

  The reason why the accelerator acceleration characteristic correction process is executed will be described. In general, the driver of the vehicle does not perform rapid acceleration when the vehicle speed Vs is relatively low (for example, when starting the vehicle). Therefore, when the command speed Vd is relatively small, the reference accelerator operation amount Aff is set to a value smaller than the accelerator operation amount Ap corresponding to the command acceleration Ad.

  For example, as understood from the broken line Laa3c, when the vehicle speed Vs is the speed Vs2, and the accelerator operation amount Ap is the fourth accelerator operation amount Ap4, the acceleration Ac is the acceleration Ac1 as understood from the broken line Laa4b. Become. On the other hand, when the command speed Vd is the speed Vs2 and the command acceleration Ad is the acceleration Ac1, the reference accelerator operation amount Aff is set to the third accelerator operation amount Ap3 as understood from the broken line Laa3c. As a result, sudden acceleration of the vehicle 10 is avoided.

(2) Accelerator Deceleration Next, an accelerator deceleration test performed to acquire vehicle characteristics (accelerator deceleration characteristics) related to accelerator deceleration of the vehicle 10 will be described.

  An example of changes with respect to time t of the accelerator operation amount Ap, the brake operation amount Bp, and the vehicle speed Vs during execution of the accelerator deceleration test is shown in the time chart of FIG. In this example, the accelerator deceleration characteristic in the vehicle 10 when the accelerator operation amount Ap is the third accelerator operation amount Ap3 is acquired.

  A curve Lv2 in FIG. 10 represents a change in the vehicle speed Vs. A broken line Lb2 represents a change in the brake operation amount Bp. A broken line La2 represents a change in the accelerator operation amount Ap.

  During the period up to time t0, the vehicle speed Vs is “0”. At this time, the accelerator operation amount Ap is “0”, and the brake operation amount Bp is the stop brake operation amount Bpp. At time t0, the brake operation amount Bp changes from the stop brake operation amount Bpp to “0”, and the vehicle speed Vs starts to increase.

  Thereafter, at time t1, the accelerator operation amount Ap changes from “0” to a predetermined reference accelerator operation amount Apr, and as a result, the acceleration Ac increases. The reference accelerator operation amount Apr is set to an accelerator operation amount Ap that can increase the vehicle speed Vs from “0” to a predetermined reference speed Vsr in a relatively short time.

  The reference accelerator operation amount Apr is larger than the third accelerator operation amount Ap3 (that is, Apr> Ap3). On the other hand, the reference speed Vsr is set to a value larger than the maximum value of the instruction speed Vd.

  Thereafter, when the vehicle speed Vs reaches the reference speed Vsr at time t2b, the accelerator operation amount Ap decreases from the reference accelerator operation amount Apr to the third accelerator operation amount Ap3. As a result, the vehicle speed Vs decreases. That is, accelerator deceleration is executed. Thereafter, at time t3b, the vehicle speed Vs reaches the speed Vs1, and the acceleration Ac becomes substantially “0”.

  As a result of the accelerator deceleration test, the relationship between the vehicle speed Vs and the acceleration Ac in the accelerator deceleration when the accelerator operation amount Ap is the third accelerator operation amount Ap3 is based on the curve Lv2 as in the case of the accelerator acceleration test. To be acquired. A combination of the acquired vehicle speed Vs and acceleration Ac is represented by a broken line Lad3 in FIG. For the accelerator operation amount Ap different from the third accelerator operation amount Ap3, the accelerator deceleration characteristic is acquired by the same accelerator deceleration test.

(3) Brake Acceleration A brake acceleration test performed to acquire vehicle characteristics (brake acceleration characteristics) related to brake acceleration of the vehicle 10 will be described.

  FIG. 11 shows an example of changes in the brake operation amount Bp, the accelerator operation amount Ap, and the vehicle speed Vs with respect to time t when the brake acceleration test is executed. In this example, the brake acceleration characteristic in the vehicle 10 when the brake operation amount Bp is the second brake operation amount Bp2 is acquired.

  A curve Lv3 in FIG. 11 represents a change in the vehicle speed Vs. A broken line Lb3 represents a change in the brake operation amount Bp. A broken line La3 represents a change in the accelerator operation amount Ap. In this example, the accelerator operation amount Ap is maintained at “0”.

  During the period up to time t0, the brake operation amount Bp is the stop brake operation amount Bpp, and the vehicle speed Vs is “0”. At time t0, the brake operation amount Bp changes from the stop brake operation amount Bpp to the second brake operation amount Bp2, and as a result, the vehicle speed Vs starts to increase due to a creep phenomenon. Thereafter, at time t2c, the vehicle speed Vs reaches the speed Vs3, and the acceleration Ac becomes substantially “0”.

  As a result of the brake acceleration experiment, the relationship between the vehicle speed Vs and the acceleration Ac in the brake acceleration when the brake operation amount Bp is the second brake operation amount Bp2 is acquired based on the curve Lv3. A combination of the acquired vehicle speed Vs and acceleration Ac is represented by a solid line Lba2 in FIG. A similar brake acceleration test is performed on the first brake operation amount Bp1 in addition to the second brake operation amount Bp2.

(4) Brake deceleration A brake deceleration test performed to acquire vehicle characteristics (brake deceleration characteristics) related to brake deceleration of the vehicle 10 will be described.

  FIG. 12 shows an example of changes with respect to time t of the brake operation amount Bp, the accelerator operation amount Ap, and the vehicle speed Vs when the brake deceleration test is executed. In this example, the brake deceleration characteristic in the vehicle 10 when the brake operation amount Bp is the third brake operation amount Bp3 is acquired.

  A curve Lv4 in FIG. 12 represents a change in the vehicle speed Vs. A broken line Lb4 represents a change in the brake operation amount Bp. A broken line La4 represents a change in the accelerator operation amount Ap.

  During the period up to time t0, the brake operation amount Bp is the stop brake operation amount Bpp, and the vehicle speed Vs is “0”. At time t0, the brake operation amount Bp changes from the stop brake operation amount Bpp to “0”. Next, at time t1, the accelerator operation amount Ap changes from “0” to the reference accelerator operation amount Apr.

  Thereafter, when the vehicle speed Vs reaches the reference speed Vsr at time t2d, the accelerator operation amount Ap changes from the reference accelerator operation amount Apr to “0”. As a result, the vehicle speed Vs starts to decrease. Next, at time t3d when the switching time Ti has elapsed from time t2d (that is, t3d = t2d + Ti), the brake operation amount Bp changes from “0” to the third brake operation amount Bp3. As a result, the magnitude of the acceleration Ac (in this case, the acceleration Ac is a negative value) increases. That is, brake deceleration is performed.

  After the magnitude of the acceleration Ac increases due to brake deceleration, the magnitude of the acceleration Ac decreases as the vehicle speed Vs decreases. That is, the acceleration Ac increases. When the acceleration Ac reaches a predetermined negative damping acceleration Acw before the vehicle 10 stops due to brake deceleration (in this example, when the vehicle speed Vs becomes the speed Vs4 at the time t4d), the brake operation amount Bp becomes the third value. The brake operation amount Bp3 changes to a predetermined damping brake operation amount Bpw. Since the damping brake operation amount Bpw is smaller than the third brake operation amount Bp3 (that is, Bpw <Bp3), the magnitude of the acceleration Ac decreases after time t4d. Next, the vehicle speed Vs becomes “0” at time t6d. That is, the vehicle 10 stops.

  If the state in which the brake operation amount Bp is the third brake operation amount Bp3 continues until the vehicle 10 stops, as represented by the broken line Lb4q in FIG. 12, the magnitude of the acceleration Ac increases until the vehicle 10 stops. A relatively large state continues. A change in the vehicle speed Vs in this case is represented by a broken line Lv4q. In this case, the vehicle 10 stops at time t5d earlier than time t6d. That is, the vehicle 10 stops suddenly.

  It is not preferable that an impact is applied to the vehicle 10 and the chassis dynamometer 30 as a result of the sudden stop of the vehicle 10. Therefore, when the brake deceleration test is executed, if the acceleration Ac becomes larger than the damping acceleration Acw (that is, when Acw <Ac <0), the brake operation amount Bp is reduced to the damping brake operation amount Bpw. The damping brake operation amount Bpw is set to a brake operation amount Bp at which the vehicle 10 does not stop suddenly.

  The process of reducing the brake operation amount Bp to the damping brake operation amount Bpw before the vehicle 10 stops is hereinafter referred to as “braking force attenuation process”. When the vehicle 10 does not stop because the brake operation amount Bp in the brake deceleration test is small (specifically, when the brake operation amount Bp is the first brake operation amount Bp1 and the second brake operation amount Bp2), the braking force is attenuated. Processing is not performed.

  As a result of this brake deceleration experiment, the relationship between the vehicle speed Vs and the acceleration Ac in the brake deceleration when the brake operation amount Bp is the third brake operation amount Bp3 is acquired based on the curve Lv4. The relationship between the vehicle speed Vs and the acceleration Ac acquired as a result of the brake deceleration test when the brake operation amount Bp is the third brake operation amount Bp3 is represented by a solid line Lbd3a and a broken line Lbd3b in FIG.

  On the other hand, the two-dot chain line Lbd3 in FIG. 7 is the same as the curve obtained by connecting the solid line Lbd3a and the broken line Lbd3c in FIG. A broken line Lbd3b represents the relationship between the vehicle speed Vs and the acceleration Ac when the braking force attenuation process is executed. On the other hand, the broken line Lbd3c is acquired by estimating the relationship between the vehicle speed Vs and the acceleration Ac when the braking force attenuation process is not executed. The process of estimating the relationship between the vehicle speed Vs and the acceleration Ac when the braking force attenuation process is not executed is hereinafter also referred to as “brake deceleration characteristic correction process”.

  Also for the brake operation amount Bp different from the third brake operation amount Bp3, the brake deceleration characteristics are respectively acquired by the same brake deceleration test.

  The relationship between the vehicle speed Vs and the acceleration Ac acquired by the brake deceleration test when the brake operation amount Bp is the fourth brake operation amount Bp4 is represented by a solid line Lbd4a and a broken line Lbd4b. The broken line Lbd4c is acquired by performing the brake deceleration characteristic correction process on the broken line Lbd4b. The two-dot chain line Lbd4 in FIG. 7 is the same as the curve obtained by connecting the solid line Lbd4a and the broken line Lbd4c in FIG.

  The relationship between the vehicle speed Vs acquired by the brake deceleration test and the acceleration Ac when the brake operation amount Bp is the fifth brake operation amount Bp5 is represented by a solid line Lbd5a and a broken line Lbd5b. The broken line Lbd5c is acquired by performing the brake deceleration characteristic correction process on the broken line Lbd5b. The two-dot chain line Lbd5 is the same as the curve obtained by connecting the solid line Lbd5a and the broken line Lbd5c.

(Significance of accelerator feedback stop condition and brake feedback stop condition)
Here, the significance of the provision of the accelerator feedback stop condition and the brake feedback stop condition will be described.

  FIG. 13 is a time chart showing changes in pedal operation that occur in accordance with changes in the command speed Vd and the vehicle speed Vs. A broken line Ld5 in FIG. 13 represents a change in the instruction speed Vd. A broken line Lv5 represents a change in the vehicle speed Vs.

  In the period from time t0 to time t2e, the command speed Vd is the speed Vs6. The command speed Vd starts decreasing at time t2e and reaches speed Vs5 at time t4e. After time t4e, the instruction speed Vd is the speed Vs5.

  In a period from time t0 to “time t1e that is earlier than time t2e by a time corresponding to the advance time”, the operation selection unit 87 selects the accelerator operation. In a period from time t1e to “time t3e that is earlier than time t4e by a time corresponding to the advance time”, the operation selection unit 87 selects the brake operation. After time t3e, the operation selection unit 87 selects the accelerator operation.

  A broken line Laf5 represents a change in the reference accelerator operation amount Aff. The reference accelerator operation amount Aff is a positive value during a period from time t0 to time t1e and a period after time t3e. On the other hand, during the period from time t1e to time t3e, the reference accelerator operation amount Aff is “0”.

  A solid line Lab5 represents a change in the basic accelerator operation amount Afp. In the period shown in FIG. 13, the basic accelerator operation amount Afp is set to “0” or a minute value.

  A broken line Lbf5 represents a change in the reference brake operation amount Bff. In the period shown in FIG. 13, the reference brake operation amount Bff is set to “0”. In other words, in the period from time t2e to time t4e, both the reference accelerator operation amount Aff and the reference brake operation amount Bff are set to “0”. That is, according to the vehicle characteristics of the vehicle 10 acquired in advance, during this period, the vehicle speed Vs is set to the indicated speed by maintaining both the accelerator operation amount Ap and the brake operation amount Bp at “0” (that is, by the engine brake). Vd can be matched.

  As understood from the broken line Lv5, the vehicle speed Vs is smaller than the command speed Vd during the period from the time t2e to the time t4e. In other words, an engine brake larger than the vehicle characteristics of the vehicle 10 acquired in advance is generated.

  A solid line Lbb5 represents a change in the basic brake operation amount Bfp. As understood from the solid line Lbb5, a state in which the basic brake operation amount Bfp becomes a positive value temporarily occurs during the period from time t2e to time t4e.

  However, since the reference brake operation amount Bff is “0” in the period from time t2e to time t4e, the condition (FB1) is satisfied. In addition, since the vehicle speed Vs is smaller than the command speed Vd during this period, the condition (FB2) is satisfied.

  That is, the brake feedback stop condition is satisfied. Therefore, during the period from time t2e to time t4e, the differential brake operation amount Bfb is set to “0”. In other words, the target brake operation amount Btg is set to “0” during this period, and therefore the brake operation is not executed.

  Thus, when the brake operation is selected by the operation selection unit 87, the brake operation amount Bp determined by the feedforward process (that is, the reference brake operation amount Bff) even if the vehicle speed Vs is smaller than the instruction speed Vd. Is “0”, the differential brake operation amount Bfb is also set to “0”. As a result, unnecessary brake operation is avoided.

  Next, an example where the accelerator feedback stop condition is satisfied will be described. FIG. 14 is a time chart showing changes in pedal operation that occur with changes in the command speed Vd and the vehicle speed Vs. A broken line Ld6 in FIG. 14 represents a change in the instruction speed Vd. A broken line Lv6 represents a change in the vehicle speed Vs.

  In the period from time t0 to time t2f, the instruction speed Vd is the speed Vs8. The command speed Vd starts decreasing at time t2f and reaches speed Vs7 at time t4f. After time t4f, the command speed Vd is the speed Vs7. In the period shown in FIG. 14, the operation selection unit 87 selects the accelerator operation.

  A broken line Laf6 represents a change in the reference accelerator operation amount Aff. The reference accelerator operation amount Aff is a positive value during a period from time t0 to time t1f and a period after time t3f. On the other hand, during the period from time t1f to time t3f, the reference accelerator operation amount Aff is “0”.

  A solid line Lab6 represents a change in the basic accelerator operation amount Afp. The basic accelerator operation amount Afp is set to “0” or a minute value during a period from time t0 to time t1f and a period after time t3f. On the other hand, during the period from time t1f to time t3f, the magnitude of the basic accelerator operation amount Afp temporarily increases.

  A broken line Lbf6 represents a change in the reference brake operation amount Bff. In the period shown in FIG. 14, the reference brake operation amount Bff is set to “0”. In other words, during the period from time t2f to time t4f, both the reference accelerator operation amount Aff and the reference brake operation amount Bff are set to “0”. That is, according to the vehicle characteristics of the vehicle 10 acquired in advance, the vehicle speed Vs can be matched with the command speed Vd by maintaining both the accelerator operation amount Ap and the brake operation amount Bp at “0” during this period. .

  A solid line Lbb6 represents a change in the basic brake operation amount Bfp. As understood from the solid line Lbb6, the basic brake operation amount Bfp is set to “0” or a minute value in the period shown in FIG.

  As understood from the broken line Lv6, the vehicle speed Vs is higher than the command speed Vd in the period from time t2f to time t4f. In other words, an engine brake smaller than the vehicle characteristics of the vehicle 10 acquired in advance is generated.

  However, since the magnitude of the difference between the vehicle speed Vs and the command speed Vd (that is, the accelerator speed difference ΔVa) is smaller than the speed threshold Vth in the period from time t2f to time t4f, the condition (FA2) is satisfied. In addition, since the reference accelerator operation amount Aff is “0” during this period, the condition (FA1) is satisfied.

  That is, the accelerator feedback stop condition is satisfied. Therefore, in the period from time t2f to time t4f, the differential accelerator operation amount Afb is set to “0”. In other words, the target accelerator operation amount Atg is set to “0” during this period, and thus the accelerator operation is not executed.

  In this way, when the accelerator operation is selected by the operation selection unit 87, if the accelerator feedback stop condition is satisfied, unnecessary execution of the accelerator operation is avoided.

(Significance of gain Ga)
Next, the significance of setting the gain Ga will be described. FIG. 15 is a diagram showing determination value Dv and gain Ga set for each driving state of vehicle 10. A polygonal line Lv7 represents a change in the instruction speed Vd.

  In the table of FIG. 15, the classification of the commanded acceleration Ad, the classification of the jerk Jk, the determination value Dv, and the gain Ga corresponding to each of the driving states of the vehicle 10 (circle Cd1 to circle Cd10) are shown. As can be understood from the gain Ga corresponding to each of the circles Cd1 to Cd10, when the driving state of the vehicle 10 changes greatly, the gain Ga is set to a large value.

  When the gain Ga is large, the differential accelerator operation amount Afb and the differential brake operation amount Bfb are set to large values as compared with the case where the gain Ga is small, so that the difference between the vehicle speed Vs and the command speed Vd is shortened. Become smaller. In other words, when the degree of change in the driving state is small, the gain Ga is small, and a sudden pedal operation is avoided.

  From the above, it is understood that the pedal operation similar to the case where the driver drives the vehicle 10 is executed by setting the gain Ga according to the degree of change in the driving state of the vehicle 10.

(Vehicle speed control process execution procedure)
Next, procedures necessary for executing the vehicle control process will be described.

(1) Installation of Vehicle 10 and Vehicle Speed Control Device 50 First, the vehicle 10 is installed on the chassis dynamometer 30. Next, the vehicle speed control device 50 is installed in the vehicle 10. Specifically, the vehicle speed control device 50 and the accelerator pedal operation amount sensor 22 are connected. In addition, the pedal actuator 71 is disposed in the vehicle interior of the vehicle 10 so that the pedal actuator 71 connected to the vehicle speed control device 50 can push the brake pedal 23. Further, the control panel 42 and the vehicle speed control device 50 are connected.

(2) Condition setting The control panel 42 is set so that the rotational resistance generated by the road roller 41 when the vehicle 10 travels matches the travel resistance when the vehicle 10 travels.

(3) Channel setting Regarding the relationship between the voltage of the vehicle speed signal Svs and the vehicle speed Vs represented by the vehicle speed signal Svs, the settings of the control panel 42 and the vehicle speed control device 50 are made to coincide with each other.

(4) Calibration With respect to the relationship between the voltage of the accelerator operation amount signal Sap and the accelerator operation amount Ap represented by the accelerator operation amount signal Sap, the setting of the vehicle speed control device 50 is matched with the setting of the control device provided in the vehicle 10. In addition, regarding the relationship between the voltage of the brake operation amount signal Sbp and the operation amount of the pedal actuator 71 corresponding to the brake operation amount signal Sbp (the amount of pushing against the brake pedal 23, that is, the brake operation amount Bp), 50 and the pedal actuator 71 are set to coincide with each other.

(5) Learning of vehicle characteristics By executing the accelerator acceleration test, the accelerator deceleration test, the brake acceleration test, and the brake deceleration test described above, the travel characteristics of the vehicle 10 are acquired (learned), and thus the pedal operation amount map is acquired. Is done.

(6) Registration of Driving Pattern The command speed Vd corresponding to each elapsed time Te is registered in the vehicle speed control device 50.

(7) Execution of vehicle speed control process The vehicle speed control process is executed.

  As described above, according to the present control device, when the reference accelerator operation amount Aff is set to “0” and when the reference brake operation amount Bff is set to “0”, that is, the vehicle 10 When it is determined that the pedal operation is unnecessary based on the vehicle characteristics, there is a high possibility that unnecessary execution of the pedal operation can be avoided. As a result, according to the present control device, there is a high possibility that the driver can perform the same pedal operation as when driving the vehicle 10.

  As mentioned above, although embodiment of the vehicle speed control apparatus which concerns on this invention was described, this invention is not limited to the said embodiment, A various change is possible unless it deviates from the objective of this invention. For example, the vehicle speed control device 50 according to the present embodiment transmits the accelerator operation amount signal Sap to the accelerator pedal operation amount sensor 22. However, the vehicle speed control device 50 may be connected to a pedal actuator that operates (pushes in) the accelerator pedal 21 and controls the pedal actuator so that the accelerator operation amount Ap becomes equal to the target accelerator operation amount Atg.

  In addition, the vehicle speed control device 50 according to the present embodiment is connected to the pedal actuator 71. However, when the vehicle 10 includes a brake pedal operation amount sensor that detects the brake operation amount Bp and the control device of the vehicle 10 controls the braking force according to the detected brake operation amount Bp, the vehicle speed control device 50 is The brake operation amount signal Sbp may be transmitted to the control device of the vehicle 10 via the brake pedal operation amount sensor and connected to the brake pedal operation amount sensor.

  In addition, the vehicle speed control device 50 according to the present embodiment is used together with the vehicle 10 and the chassis dynamometer 30. However, the vehicle speed control device 50 may be used together with a VRS (Virtual Real Simulator) including a vehicle driving engine and a simulator that behaves as a vehicle constituent device other than the engine.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 21 ... Accelerator pedal, 22 ... Accelerator pedal operation amount sensor, 23 ... Brake pedal, 24 ... Drive wheel, 25 ... Steering wheel, 30 ... Chassis dynamometer, 41 ... Road roller, 42 ... Control panel, 50 ... Vehicle speed control device 71 ... Pedal actuator.

Claims (1)

Acquire the travel speed of the vehicle that controls the driving force and the braking force according to the accelerator operation amount that is 0 or more that represents the operation amount of the accelerator pedal and the brake operation amount that is 0 or more that represents the operation amount of the brake pedal. A vehicle speed acquisition unit,
The target accelerator operation amount and the target brake operation amount for making the travel speed coincide with a predetermined command speed that changes with time so that at least one of the target accelerator operation amount and the target brake operation amount is zero. A target operation amount setting section to be set;
An accelerator operation amount signal that is a signal that represents the target accelerator operation amount and a signal that represents the target brake operation amount so that the driving force and braking force of the vehicle are controlled according to the target accelerator operation amount and the target brake operation amount. A signal output unit for outputting a brake operation amount signal,
A vehicle speed control device comprising:
In the accelerator pedal operation amount map, which is a previously acquired relationship between the combination of the travel speed and the accelerator operation amount and the acceleration of the vehicle corresponding to the combination, the instruction speed and the unit of the instruction speed A value obtained by applying an indicated acceleration that is a change amount per time is obtained as a reference accelerator operation amount, a combination of the travel speed and the brake operation amount, and an acceleration of the vehicle corresponding to the combination, A reference operation amount acquisition unit that acquires, as a reference brake operation amount, a value obtained by applying the instruction speed and the instruction acceleration to a brake pedal operation amount map that is a previously acquired relationship between
The differential accelerator operation amount that increases as the accelerator speed difference obtained by subtracting the command speed from the travel speed increases, and the differential brake operation amount that increases as the brake speed difference obtained by subtracting the command speed from the travel speed increases. And a differential operation amount acquisition unit for acquiring
With
The target manipulated variable setting unit
The process of acquiring the sum of the reference accelerator operation amount and the differential accelerator operation amount as the target accelerator operation amount, or the sum of the reference brake operation amount and the differential brake operation amount is acquired as the target brake operation amount. Execute the process,
The differential operation amount acquisition unit
If the reference accelerator operation amount is 0 and the magnitude of the accelerator speed difference is less than or equal to a predetermined speed threshold, the difference accelerator operation amount is set to 0,
If the reference brake operation amount is 0 and the magnitude of the brake speed difference is a negative value, the difference brake operation amount is set to 0.
A vehicle speed control device configured as described above.

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