JP4910532B2 - Vehicle travel control device and vehicle travel control method - Google Patents

Description

  The present invention relates to a vehicular travel control device that maintains the stability of a vehicle, and in particular, estimates a vehicle state using road surface reaction force torque during travel, and drives the vehicle based on the estimated vehicle state. The present invention relates to a vehicular travel control device and a vehicular travel control method.

  As a conventional vehicular travel control device, the vehicle's turning state is estimated by detecting the yaw rate. Based on the estimation result, the vehicle's yaw rate behavior is reduced to eliminate understeer and oversteer. There has been a behavior control device controlled by a continuously variable transmission that shifts in stages (see, for example, Patent Document 1).

  In addition, the degree of grip representing the degree of lateral grip with respect to the wheels is estimated, and when the grip degree is determined to be less than a predetermined value, the vehicle is decelerated by executing any one of braking control, throttle control, and shift control. There has been a motion control device (see, for example, Non-Patent Document 2).

JP 2001-191820 A JP 2003-31465 A

  In the behavior control device of Patent Document 1, the difference between the target yaw rate and the actual yaw rate is used in order to determine the unstable state of the running vehicle. Therefore, since driving torque is controlled after the vehicle itself becomes unstable, there is a problem that sufficient behavior control using driving torque cannot be performed.

  Further, in the motion control device of Patent Document 2, deceleration is performed by braking control, throttle, or shift control based on the estimated grip degree, but as soon as the vehicle becomes unstable, the driver's will There was a problem that the vehicle decelerated regardless of the vehicle.

  The present invention has been made to solve such a problem, and performs control to maintain the stability of the vehicle without decelerating against the driver's will before the vehicle becomes completely unstable. An object of the present invention is to provide a vehicular travel control apparatus and a vehicular travel control method that do not decelerate contrary to the will of the driver as soon as an unstable state occurs.

The vehicle travel control apparatus according to the present invention calculates a road surface reaction force torque detecting means for detecting a road surface reaction force torque received by a vehicle tire from the road surface, and calculates a standard road surface reaction force torque during normal travel from the travel state quantity of the vehicle. The difference between the road surface reaction force torque and the reference road surface reaction force torque from the reference road surface reaction force torque calculated from the detected road surface reaction force torque or the calculated road surface reaction force torque, or the road surface reaction force torque Vehicle state calculation means for calculating the ratio of the reference road surface reaction torque and the drive torque control means for controlling the drive torque transmitted to the drive wheels. The drive torque control means is calculated by the vehicle state calculation means. until the deviation or the percentage that is found when the vehicle is changed more than a predetermined value than the value a ₀ of the difference or the ratio of the time of steady state, the accelerator is returned, the deviation Others in a range not decelerated from the vehicle speed V ₀ which changes the time of the above-mentioned ratio, according to the calculated the difference or the value of the ratio, and has a suppressing drive torque restraining means the drive torque.

The vehicle travel control method according to the present invention includes a first step of detecting a road surface reaction force torque received by a vehicle tire from a road surface, and a second step of calculating a reference road surface reaction force torque during normal travel from the travel state quantity of the vehicle. A deviation between the road surface reaction force torque and the reference road surface reaction force torque or a difference between the road surface reaction force torque and the reference road surface reaction force torque from the detected road surface reaction force torque and the calculated road surface reaction force torque. A third step of calculating a ratio with the above deviation or the ratio, when the calculated deviation or the ratio changes more than a predetermined value from the deviation or the ratio value A ₀ when the vehicle is in a stable state. A fourth step of calculating a drive torque correction amount according to the value, a fifth step of correcting a value of a target drive torque to be transmitted to the drive wheels based on the calculated drive torque correction amount, an accelerator In the on state, the vehicle speed is, outputs the target driving torque which is corrected if Hayakere than the vehicle speed V ₀ which time the aforementioned difference or the ratio is changed, the vehicle speed V ₀ as late than the same or the vehicle speed V ₀ and the vehicle speed V ₀ target those having a sixth steps of outputting a drive torque.

  According to the vehicle travel control device and the vehicle travel control method of the present invention, the vehicle state is calculated based on the reference road surface reaction torque and the road surface reaction torque, and the calculated vehicle state changes from the stable state. Before the vehicle becomes completely unstable, the driving force torque is suppressed in a range that does not decelerate from the vehicle speed at the time of change, so when the driver wants to accelerate, the acceleration or current vehicle speed should be set within a range that does not affect safety. Can be maintained.

Embodiment 1 FIG.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a block diagram showing a vehicle travel control apparatus according to Embodiment 1 of the present invention.
The vehicle travel control apparatus according to the first embodiment includes a road surface reaction force torque detecting means 101 for detecting road surface reaction force torque received by a vehicle tire from the road surface, and a vehicle running state amount (here, a steering wheel angle and a vehicle speed). The road surface reaction force detected by the road surface reaction force torque detecting means 101 and the reference road surface reaction force torque calculating means 102 for calculating the road surface reaction force torque that the tire receives from the road surface during normal driving with respect to the above-described running state amount. The vehicle state calculation means 103 for calculating the running state of the vehicle using the torque and the reference road surface reaction force torque calculated by the reference road surface reaction force torque calculation means 102, the vehicle running state amount, the detection result, the calculation result, etc. A memory (not shown) for storing and a drive torque control means 104 for controlling the drive torque transmitted to the drive wheels of the vehicle are provided.

The operation of the first embodiment will be described based on the flowchart of FIG.
First, the road surface reaction torque detection means 101 detects the road surface reaction torque and stores it in the memory (step S101).
Next, the standard road surface reaction torque is calculated by the standard road surface reaction torque calculating means 102 and stored in the memory (step S102).
Next, the difference between the road surface reaction torque stored in the memory and the reference road surface reaction torque or the ratio (ratio) between the road surface reaction torque and the reference road surface reaction torque is calculated by the vehicle state calculation means 103 and stored in the memory. (Step S103).
Next, the drive torque control means 104 determines whether there is a change in the deviation or ratio calculated in step S103. If there is a change in the deviation or the ratio, step S105 is executed, and if there is no change, the process returns to the start (step S104).
In step S105, the drive torque control means 104 controls the drive torque so as to suppress the drive torque transmitted to the drive wheels and to accelerate or maintain the current vehicle speed within a range that does not affect the safety of the vehicle. That is, until the driver returns the accelerator, the drive torque transmitted to the drive wheels is suppressed within a range that does not decelerate from the vehicle speed at the time of the deviation or rate change.
Next, the drive torque control means 104 determines whether the deviation or ratio is greater than or less than a predetermined value (step S106). Note that the above predetermined value is a tire force limit from an actual vehicle test (where the tire force indicates a road reaction force torque generated between the tire and the road surface, and the tire force limit is a road reaction force torque). The predetermined value is a value that defines the saturation point of.
If the deviation or the ratio (when the road surface reaction force torque is used as a reference) is equal to or greater than a predetermined value, the drive torque is controlled so that the vehicle speed does not increase from the vehicle speed when it exceeds the predetermined value (step S107). In step S107, it is not accelerated. If the deviation or ratio (based on the road surface reaction force torque) is equal to or smaller than a predetermined value in step S106, the process returns to the start.
In step S106 in FIG. 2, it is determined whether or not the deviation or the ratio based on the road surface reaction force torque is equal to or greater than a predetermined value. However, when the ratio is calculated based on the reference road surface reaction torque, In step S106, it is determined whether or not the calculated ratio value is equal to or less than a predetermined value. If it is equal to or less than the predetermined value, the driving torque is set so that the vehicle speed does not increase from the vehicle speed when the value is equal to or less than the predetermined value in step S107. If it is greater than or equal to the predetermined value, return to the start.

  Here, the road surface reaction force torque detecting means 101 estimates the road surface reaction force torque from the steering torque of the driver and the assist torque of the electric power steering as proposed in, for example, Japanese Patent Laid-Open No. 2005-324737. Alternatively, the road surface reaction force torque may be directly measured using a load cell or the like, and a known technique may be used.

  The standard road surface reaction torque calculation means 102 is, for example, as proposed in Japanese Patent Application Laid-Open No. 2005-324737, the steering wheel angle (actual steering angle), the vehicle traveling speed (vehicle speed), and the standard road surface reaction force torque. The reference road surface reaction torque can be calculated using the steering wheel angle / travel speed-reference road surface reaction torque map that describes the relationship between the yaw rate generated in the vehicle and the steering angle (actual steering angle). In conversion, the standard road surface reaction torque may be calculated from the steering wheel angle / travel speed-standard road surface reaction torque map. Alternatively, the lateral road G (lateral acceleration) generated in the vehicle may be converted into a steering wheel angle (actual steering angle), and the standard road surface reaction torque may be calculated from the steering wheel angle / traveling speed-standard road surface reaction torque map. A known technique may be used.

FIG. 3 shows an example of the configuration of the vehicle state calculation means 103. When calculating the deviation, the adder / subtractor 301 subtracts the road surface reaction force torque from the reference road surface reaction force torque to calculate the deviation of the road surface reaction force torque. The calculated value is multiplied by the gain value K ₁ by the proportional gain 302 and used as the output of the vehicle state calculating means 103.
Here, assuming that the deviation between the reference road surface reaction torque and the road surface reaction torque is α ₁ , the reference road surface reaction torque is Talign_ref, and the road surface reaction force torque is Talign, the output α ₁ of the vehicle state calculation means 103 is given by Can be represented.

FIG. 4 shows another configuration example of the vehicle state calculation means 103. By subtracting the road surface reaction torque from the reference road surface reaction torque calculating the deviation of the road surface reaction torque at subtracter 401, a value obtained by multiplying the gain value K ₁ in the calculated value by a proportional gain 402, the road surface reaction force perform differentiated the deviation of the torque at the differentiator 403, as an output alpha ₁ of the vehicle state calculating section 103 and a value obtained by multiplying the gain value K ₂ on the differential value are summed in adder 405 with the differential gain 404 Yes. This calculation can be expressed by the following equation.

なお、上式においてｄ／ｄｔは時間微分を示している。

In the above equation, d / dt indicates time differentiation.

FIG. 5 shows still another configuration example of the vehicle state calculation means 103. Using the reference road surface reaction torque as a reference, the divider 501 divides the road surface reaction torque by the reference road surface reaction torque to calculate a ratio, which is used as the output α ₂ of the vehicle state calculation means 103. This calculation can be expressed by the following equation.

Further, as shown in FIG. 6, with reference to the road surface reaction force torque, the divider 601 calculates the ratio by dividing the reference road surface reaction torque by the road surface reaction force torque, and outputs α ₃ of the vehicle state calculation means 103. This calculation can be expressed by the following equation.

  FIG. 7 shows the configuration of the drive torque control means 104. The drive torque control means 104 has drive torque suppression means 701 that suppresses drive torque. The drive torque suppression means 701 has a relationship between the deviation or ratio calculated by the vehicle state calculation means 103, the target drive torque (accelerator depression amount for achieving the target vehicle speed, and the detected actual vehicle speed). The accelerator pedal depression amount / traveling speed-target driving torque map (generally calculated by the type of engine) is input, and the above-described deviation or ratio is transmitted to the driving wheel. The target drive torque value is corrected, and the corrected target drive torque is output.

Further, the drive torque control means 104 has a configuration necessary for controlling the drive torque. For example, as disclosed in Japanese Patent Laid-Open No. 5-206811, an accelerator pedal and an accelerator pedal are provided in the engine intake passage. A mechanical throttle valve that operates in conjunction with a motor throttle valve that is driven to open and close by a throttle motor is arranged in series to control a driving torque that is an engine output, or as disclosed in Japanese Patent Laid-Open No. 5-278623. The drive torque is controlled by controlling a shift solenoid valve that controls the transmission gear ratio.
In addition, the present embodiment can be applied to any vehicle having a travel control device that can control drive torque.

Below, the main operation | movement of the drive torque suppression means 701 by this Embodiment is demonstrated.
FIG. 8A shows a time response waveform (solid line) of the reference road surface reaction torque and a time response waveform (dashed line) of the road surface reaction force torque when the drive torque is not controlled, and the accelerator is on. When the vehicle is in a stable state, the standard road surface reaction torque and the road surface reaction torque torque match, but when the vehicle starts to become unstable (understeer state), the standard road surface reaction torque increases as time passes. There is a characteristic that a deviation occurs between the force torque and the road surface reaction torque.
FIG. 8B is a time change waveform of the deviation (α ₁ ) generated corresponding to the time response waveform of FIG. In FIG. 8B, the deviation value when the vehicle is in a stable state is A ₀ (A ₀ = 0), the time when the deviation starts to change from A ₀ is t ₀ , and the deviation at the tire force limit time is shown. The value is A ₁ , and the point in time when the calculated deviation becomes A ₁ without control is t ₂ .
FIG. 8C is a diagram for explaining the drive torque control method according to the present embodiment. The solid line indicates the speed change when the control according to the present embodiment is performed, and the broken line indicates the speed change when there is no control. Show.
In the present embodiment, the drive torque suppression means 701 suppresses the drive torque of the vehicle according to the calculated deviation value within a range not decelerating from the vehicle speed V ₀ when the deviation changes. That is, as shown by a solid line in FIG. 8C, in the first section (acceleration possible section) from time t ₀ to time t ₁ , the degree of acceleration of the vehicle speed is not controlled according to the calculated deviation value (broken line) ) (In FIG. 8C, time t ₀ + Δt to time t ₁ ). Further, when the deviation α ₁ between the standard road surface reaction torque and the road surface reaction torque becomes a predetermined value A ₁ , the drive torque is not increased from the time t ₁ when the deviation reaches the predetermined value A _1. The vehicle speed V ₁ (limit vehicle speed) at time t ₁ is maintained (limit vehicle speed maintenance section: second section).

In this way, since the vehicle can be accelerated as much as possible from the deviation occurrence time t ₀ , the driver's will can be respected until the driver returns the accelerator, and the vehicle tire force The vehicle speed can be maintained at the limit.
FIG. 8 (d) shows changes in vehicle speed when the conventional drive torque control method is applied. Unlike the present invention, the driving torque is not controlled until time t ₂ when the calculated deviation becomes A _1, and the vehicle speed is controlled to the limit vehicle speed at time t ₂ when the deviation reaches the predetermined value A ₁ .

FIG. 9 is a diagram for explaining the operation of the drive torque suppressing means 701 when the ratio α ₂ is calculated with reference to the standard road surface reaction torque.
FIG. 9A shows a time response waveform (solid line) of the reference road surface reaction torque and a time response waveform (dashed line) of the road surface reaction torque when the driving torque is not controlled. FIG. 9B shows the time response of the ratio α ₂ when the ratio α ₂ is calculated with reference to the standard road surface reaction torque with respect to the time response waveform of FIG. When the ratio α ₂ is calculated based on the reference road surface reaction torque, when the vehicle starts to become unstable (time point t ₀ ), the road surface reaction torque becomes smaller than the reference road surface reaction torque. The reference road surface reaction torque becomes larger, and the ratio α ₂ becomes smaller than the ratio when the vehicle is stable (A ₀ = 1).
In the driving torque suppression unit 701, when it is determined that the ratio α ₂ calculated by the vehicle state calculation unit 103 is smaller than the stable state ratio A ₀ = 1, as shown by a solid line in FIG. in the time t ₀ ~ ratio alpha ₂ is the predetermined value a ₁ and since the time t ₁ of the first section (acceleration-probable section), as compared to the acceleration of the vehicle to the control without (dashed line), moderately (Fig. 9 (c ) At time t ₀ + Δt to time t ₁ ). Further, when the ratio α ₂ between the reference road surface reaction torque and the road surface reaction torque decreases to a predetermined value A ₁ , the drive torque is not increased from the time t ₁ when the ratio α ₂ reaches the predetermined value A _1. The driving torque of the vehicle is suppressed and the vehicle speed V ₁ (limit vehicle speed) at time t ₁ is maintained (limit vehicle speed maintenance section: second section).
In this way, the vehicle can be accelerated as much as possible from the rate change time t ₀ , so that the driving force is not decelerated from the vehicle speed V ₀ at the rate change time t ₀ until the driver returns the accelerator. By suppressing this, the driver's will can be respected, and the vehicle speed can be maintained at the limit of the tire force of the vehicle.

FIG. 10 is a diagram for explaining the operation of the drive torque suppressing means 701 when the ratio α ₃ is calculated based on the road surface reaction torque.
FIG. 10B shows a time response waveform (solid line) of the reference road surface reaction torque and a time response waveform (broken line) of the road surface reaction torque when the drive torque is not controlled (FIG. 10A). On the other hand, the time response of the ratio α ₃ when the ratio α ₃ is calculated based on the road surface reaction torque is shown. When the ratio α ₃ is calculated based on the road surface reaction torque, when the vehicle starts to become unstable (time point t ₀ ), the road surface reaction torque becomes smaller than the reference road surface reaction torque, so the road surface used as a reference The reaction torque becomes smaller and the ratio α ₃ becomes larger than the ratio when the vehicle is stable (A ₀ = 1).
In the drive torque suppressing means 701, when it is determined that the ratio α ₃ calculated by the vehicle state calculating means 103 is larger than the stable state ratio A ₀ = 1, as shown by a solid line in FIG. in the time t ₀ ~ ratio alpha ₃ exceeds a predetermined value a ₁ and since the time t ₁ of the first section (acceleration-probable section), as compared to the acceleration of the vehicle to the control without (dashed line), moderately (Fig. 10 (c ) At time t ₀ + Δt to time t ₁ ). Further, when the ratio α ₃ between the reference road surface reaction torque and the road surface reaction torque increases to a predetermined value A ₁ , the drive torque is not increased from the time t ₁ when the ratio α ₃ reaches the predetermined value A _1. The driving torque of the vehicle is suppressed and the vehicle speed V ₁ (limit vehicle speed) at time t ₁ is maintained (limit vehicle speed maintenance section: second section).
In this way, the vehicle can be accelerated as much as possible from the rate change time t ₀ , so that the driving force is not decelerated from the vehicle speed V ₀ at the rate change time t ₀ until the driver returns the accelerator. By suppressing this, the driver's will can be respected, and the vehicle speed can be maintained at the limit of the tire force of the vehicle.

The operation of the drive torque suppression unit 701 will be further described. FIG. 11 shows a detailed flowchart of step S105 of the flowchart of FIG.
In step S104 of the flowchart of FIG. 2, if there is a change in the deviation or ratio, in step S201, the deviation or ratio between the reference road reaction force torque and the road surface reaction torque calculated by the vehicle state calculation unit 103 is stable. The vehicle speed V ₀ at the time point t ₀ when the state value A ₀ is changed is detected, and the detected vehicle speed V ₀ is stored in the memory.
Next, in step S202, the correction amount of the target drive torque is calculated based on the deviation or the ratio calculated by the vehicle state calculation means 103.

FIG. 12 shows the correction amount of the target drive torque, and FIG. 12A shows the correction amount of the drive torque according to the deviation α ₁ between the standard road reaction torque and the road reaction torque. In FIG. 12A, the value of the correction amount when the vehicle is in a stable state (deviation A ₀ = 0) is set to 1, and the correction amount is changed until the deviation α ₁ increases to a predetermined value A ₁ (first section). It is set to be continuously smaller.
FIG. 12B shows the amount of correction of the drive torque according to the ratio α ₂ calculated with reference to the reference road surface reaction force torque. The value of the amount of correction when the vehicle is in a stable state (deviation A ₀ = 1) is set to 1. The correction value is set to be continuously decreased until the ratio α ₂ decreases to the predetermined value A ₁ (first interval).
FIG. 12C shows the amount of correction of the drive torque according to the ratio α ₃ calculated based on the road surface reaction force torque. The value of the amount of correction when the vehicle is in a stable state (deviation A ₀ = 1) is set to 1. Until the ratio α ₃ increases to the predetermined value A ₁ (first interval), the correction amount is set to be continuously decreased.

In FIG. 12, the deviation α ₁ or the ratios α ₂ and α ₃ are close to the stable state value A ₀ (region S in FIG. 12), but the value of the correction amount remains unchanged and remains 1. By providing such a flat region S in the vicinity of A ₀ , as shown in FIGS. 8C, 9C, and 10C, the deviation α ₁ or the ratios α ₂ , α ₃ However, since the driving torque is not suppressed immediately at time t ₀ and is gradually suppressed from time t ₀ + Δt, there is no sense of incongruity.

In FIG. 12, a flat region S is provided in the correction amount in the first section, but such a region S is not provided in the first section, and the deviation α ₁ or the ratios α ₂ and α ₃ have values. Accordingly, the correction amount may be changed uniformly. In this case, immediately the driving torque from the time t ₀ is suppressed.
Such a setting method of the driving torque correction amount may be determined from the result obtained in the actual vehicle test.

Next, in step S203, the value of the target drive torque is corrected by multiplying the input target drive torque by the drive torque correction amount obtained based on the deviation or ratio.
Next, in step S204, it is determined whether the vehicle speed is faster than the vehicle speed V ₀ at the time of change stored in the memory. If the vehicle speed is high, the corrected target drive torque is output (step S205). If the vehicle speed is slow, a target drive torque that is the vehicle speed V ₀ at the time of change is output (step S206).

In this way, if the deviation or ratio changes, the driving torque is suppressed until the driver returns the accelerator, and the deviation is corrected by correcting the target driving torque in a range that does not decelerate from the vehicle speed at the time when the deviation or ratio changes. Alternatively, since the vehicle can be accelerated as much as possible from the time t ₀ when the ratio changes, the driver's will can be respected, and the vehicle speed can be maintained at the limit of the tire force of the vehicle.
In the first section, since the output of the drive torque control means is continuously changed according to the deviation or the ratio, it is possible to provide a vehicular travel control device that does not give the driver a sense of incongruity.

FIG. 13 shows a detailed flowchart of step S107 in the flowchart of FIG.
In step S106 of the flowchart of FIG. 2, when the deviation or ratio is a predetermined value A _1, at step S301, the deviation or ratio detecting vehicle speed (limit speed) V ₁ time t ₁ which reaches the predetermined value A ₁ Then, the detected limit vehicle speed V ₁ is stored in the memory.
Next, in step S302, the target drive torque as a critical vehicle speed V _1, namely, calculates a target driving torque which the vehicle can travel in a safe range, in step S303, and outputs the calculated target drive torque.

  As described above, in the present embodiment, the vehicle speed decelerates from the vehicle speed at the time of change until the driver returns the accelerator from the time when the deviation or ratio between the reference road surface reaction torque and the road surface reaction torque changes or near the change time. Since the driving force is suppressed within a range that is not allowed to be accelerated, the acceleration or the current vehicle speed can be maintained within a range that does not affect safety.

In this embodiment, the determination of the saturation point (limit of tire force) of the road surface reaction torque is a low-pass when estimating the road surface reaction torque, as proposed in Japanese Patent Application Laid-Open No. 2005-324737. When the time constant of the filter is not optimal, the saturation point of the road reaction force torque is obtained from the deviation between the standard road reaction torque and the road reaction torque using the value obtained by correcting the road reaction torque with the friction torque. Alternatively, as proposed in Japanese Patent Laid-Open No. 2003-160042, the peak point of the road surface reaction force torque at which the absolute value of the road surface reaction torque turns from an increase to a decrease as the absolute value of the steering angle increases. May be determined as the saturation point of the road surface reaction torque.
Further, as proposed in Japanese Patent Application Laid-Open No. 2003-341538, the vehicle state is detected using the alignment torque received from the road surface and the side slip angle β, and the slope of the alignment torque with respect to the side slip angle is determined from the slope of the approximate straight line. If it is greatly different, it may be determined that the road surface reaction force torque is saturated, and other known techniques may be used.

Further, in the present embodiment, the vehicle state calculation means 103 calculates either a deviation or a ratio between the reference road surface reaction torque and the road surface reaction force torque, and the drive torque control means 104 calculates any one of the calculated deviation or ratio. Although the driving torque is controlled by the vehicle state calculating means 103, both the deviation and the ratio are calculated, and the driving torque control means 104 combines the calculated deviation and the ratio, and either the deviation or the ratio changes. Alternatively, the driving torque may be suppressed within a range that does not decelerate from the vehicle speed V ₀ at the time of deviation or rate change until the driver returns the accelerator from around the time of change.
Further, after either the deviation or the ratio reaches the predetermined value, the drive torque may be suppressed so as not to exceed the vehicle speed V ₁ at the time when the predetermined value is reached.

  Further, in the present embodiment, the engine control has been described with respect to output torque control. However, the engine control may be applied to other devices that control the vehicle speed, and any known system that can control the vehicle speed is known. Technology can be used.

1 is a block diagram showing a vehicle travel control apparatus according to Embodiment 1 of the present invention. It is a flowchart which shows operation | movement of the vehicle travel control apparatus by Embodiment 1 of this invention. It is a figure which shows the structure of the vehicle state calculating means which concerns on Embodiment 1 of this invention. It is a figure which shows the other structure of the vehicle state calculating means which concerns on Embodiment 1 of this invention. It is a figure which shows the further another structure of the vehicle state calculating means which concerns on Embodiment 1 of this invention. It is a figure which shows the further another structure of the vehicle state calculating means which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the drive torque control means which concerns on Embodiment 1 of this invention. It is a figure explaining the control action of the drive torque control means concerning Embodiment 1 of this invention. It is a figure explaining other control operations of the drive torque control means concerning Embodiment 1 of this invention. It is a figure explaining the further another control action of the drive torque control means concerning Embodiment 1 of this invention. It is a flowchart which shows a part of operation | movement of the drive torque control means based on Embodiment 1 of this invention. It is a figure explaining operation | movement of the drive torque suppression means which concerns on Embodiment 1 of this invention. It is a flowchart which shows a part of operation | movement of the drive torque control means based on Embodiment 1 of this invention.

Explanation of symbols

  101 road surface reaction force torque detection means, 102 standard road surface reaction torque calculation means, 103 vehicle state calculation means, 104 drive torque control means, 701 drive torque suppression means.

Claims (5)

Road surface reaction force torque detecting means for detecting road surface reaction force torque received by the tire of the vehicle from the road surface, reference road surface reaction force torque calculating means for calculating a reference road surface reaction force torque during normal running from the running state amount of the vehicle, detected Based on the road surface reaction force torque and the calculated standard road surface reaction torque, the difference between the road surface reaction force torque and the reference road surface reaction torque or the ratio of the road surface reaction force torque and the reference road surface reaction torque is Vehicle state calculation means for calculating, and drive torque control means for controlling the drive torque transmitted to the drive wheels,
The drive torque control unit, the deviation or the percentage calculated by the vehicle state calculating means, when the vehicle has changed more than a predetermined value than the value A ₀ of the difference or the ratio of the time of steady state, the accelerator is returned Until the vehicle speed V ₀ at the time of the change of the deviation or the ratio, a drive torque suppressing means for suppressing the drive torque according to the calculated value of the deviation or the ratio is provided. A vehicle travel control device. Vehicle A ₀ values of deviation or percentage of time in a stable state, the calculated deviation or percentage above A t ₀ altered when more than a predetermined value than _0, V ₀ a vehicle speed at time t _0, the road surface reaction torque the value of the deviation or percentage of saturated point as a _1, until the calculated deviation or ratio is the a _1, computed according to the value of the deviation or the ratio, can accelerate while suppressing the driving torque and then, at time t ₁ the deviation becomes a _1, the vehicle control system which comprises suppressing the driving torque so as not to exceed the vehicle speed V ₁ of the time point t _1. The vehicle travel control apparatus according to claim 1, wherein the predetermined value is a value that defines a limit of tire force. The drive torque suppression means corrects the target drive torque transmitted to the drive wheels in the first section with a correction amount that continuously changes according to the value of the deviation or ratio calculated by the vehicle state calculation means,
The vehicle travel control apparatus according to any one of claims 1 to 3, wherein the target drive torque is suppressed. A first step of detecting a road surface reaction force torque received by a vehicle tire from the road surface; a second step of calculating a reference road surface reaction force torque during normal driving from a vehicle running state amount; A third step for calculating a deviation between the road surface reaction force torque and the reference road surface reaction torque or a ratio between the road surface reaction force torque and the reference road surface reaction torque from the reference road surface reaction torque When the deviation or the ratio is changed by a predetermined value or more from the deviation or the ratio value A ₀ when the vehicle is in a stable state, a driving torque correction amount corresponding to the deviation or the ratio value is calculated. Fourth step, fifth step of correcting the value of the target drive torque transmitted to the drive wheel based on the calculated drive torque correction amount, the accelerator being in the on state, and the vehicle speed being the deviation or If Hayakere than the vehicle speed V ₀ which time the serial rate is changed and outputs the corrected target driving torque, the sixth steps of outputting the target drive torque as a vehicle speed V ₀ as late than the same or the vehicle speed V ₀ and the vehicle speed V ₀ A vehicle travel control method comprising the vehicle.

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