JP4849238B2 - Vehicle travel control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the traveling movement of a vehicle optimally by optimizing the controlled variable of each control means while restraining any increase in operation load and consumption energy, in a vehicle including a steering control means, a braking/driving force control means, and a grounding load control means. <P>SOLUTION: When the vehicle requires urgent traveling movement control (440, 450), evaluation functions of all control means are computed to allot a target traveling movement controlled variable of the whole vehicle to all control means, thereby computing a target controlled variable of each control means (700). When the vehicle does not require urgent traveling movement control, a target controlled variable of a specified control means is computed based on the traveling state of the vehicle, a change amount of physical quantity of the vehicle due to the control of the specified control mens is computed based on the target controlled variable of the specified control means, thereby computing a target controlled variable of another control means based on the target traveling movement controlled variable of the whole vehicle and the change amount of physical quantity (500, 600). <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a vehicle travel control device, and more particularly, to a vehicle travel control device including a plurality of behavior control means for controlling the behavior of a vehicle in cooperation with each other.

  As one of travel control devices for vehicles such as automobiles, for example, as described in Patent Document 1 below, a plurality of behavior control means for controlling the behavior of a vehicle in cooperation with each other by different actions, and stabilizing the vehicle For calculating the target behavior control amount for the entire vehicle for the purpose of traveling, and allocating the target behavior control amount for the entire vehicle to the plurality of behavior control means according to the behavior control characteristics of the plurality of behavior control means. A travel control device having distribution control means for controlling a plurality of behavior control means based on the above is already known.

In the travel control device described in Patent Document 1 below, the plurality of behavior control means are independent of the steering control means for steering the wheels regardless of the steering operation by the driver and the braking / driving operation by the driver. The braking / driving force control means that can control the braking / driving force of each wheel individually. The distribution control means slips each wheel as a solution that brings the evaluation function set for the longitudinal force, lateral force, and yaw moment of the vehicle closer to zero. The target slip rate and the target slip angle of each wheel are calculated based on the correction amount and the steering control means and the braking / driving force control based on the target slip rate and the target slip angle. Control means.
JP 2003-159966 A

  Generally, in a vehicle such as an automobile, the ground load of each wheel can be controlled by an active suspension device or the like, and the traveling motion of the vehicle can also be controlled by controlling the ground load of each wheel. . In addition, the control effect of the traveling motion of the vehicle by the steering control means and the braking / driving force control means is affected by the ground load of each wheel.

  However, in the travel control device described in the above publication, the plurality of behavior control means are a steering control means and a braking / driving force control means, and the distribution control means is a target behavior control amount for the entire vehicle by calculating an evaluation function. Is distributed to the steering control means and the braking / driving force control means. In addition to the steering control means and the braking / driving force control means, the ground load of each wheel can be controlled as an active suspension device as a plurality of behavior control means. In order to optimally control the running motion of a vehicle, the target behavior control amount of the entire vehicle is applied to the steering control means, braking / driving force control means, and ground load control means. No investigation has been made as to whether or not the vehicle should be distributed. Accordingly, the vehicle described in the above-mentioned publication is applied to a vehicle equipped with steering control means, braking / driving force control means, and ground load control means. It can not be applied a control device.

  Further, the steering control means, the braking / driving force control means, and the ground load control means each have a characteristic in controlling the traveling motion of the vehicle, and depending on the traveling state of the vehicle, the target behavior control amount of the entire vehicle is controlled by the steering control means, Rather than distributing the braking / driving force control means and the ground load control means to all, it is preferable to control by giving priority to a specific control means by paying attention to the traveling state of the vehicle and the characteristics of each control means.

  In addition, there are many calculation parameters when trying to always distribute the target behavior control amount of the entire vehicle to all the control means by calculating the evaluation function for all of the steering control means, the braking / driving force control means, and the ground load control means. As a result, it is inevitable that the calculation load is constantly increased, and the control of each control means is compared to the case where there are two types of control means as in the case of the travel control device described in Patent Document 1. Although the amount is reduced, there is a problem that energy consumption increases due to the operation of all the control means.

  The present invention has been made in view of the above-described problems in the conventional vehicle travel control device configured to distribute the target behavior control amount of the entire vehicle to the steering control means and the braking / driving force control means by calculating the evaluation function. The main object of the present invention is to determine a traveling state of a vehicle in a vehicle including a steering control unit, a braking / driving force control unit, and a ground load control unit as a plurality of traveling motion control units. By changing the distribution mode of the target behavior control amount of the entire vehicle with respect to the steering control means, braking / driving force control means, and ground load control means according to the running conditions of the vehicle and the characteristics of each control means, the calculation load and energy consumption In other words, the control amount of each control means is optimized while suppressing the increase of the vehicle, and the running motion of the vehicle is optimally controlled.

[Means for Solving the Problems and Effects of the Invention]
According to the present invention, the main problem described above is the structure of claim 1, that is, a plurality of traveling motion control means for controlling the traveling motion of the vehicle in cooperation with each other by different actions, and the vehicle is allowed to travel stably. Means for calculating a target travel motion state quantity for the vehicle, means for calculating a target travel motion control amount for the entire vehicle for making the travel motion state quantity of the vehicle the target travel motion state quantity, Control means for calculating a target control amount for each of the plurality of traveling motion control means based on the target traveling motion control amount, and controlling the plurality of traveling motion control means based on the corresponding target control amounts. In the vehicle travel control device, the plurality of travel motion control means includes a ground load control means for controlling a ground load of each wheel, and a steering capable of steering the wheels regardless of a steering operation by a driver. Control means, and braking / driving force control means capable of individually controlling the braking / driving force of each wheel regardless of the braking / driving operation by the driver, the control means performing running motion control when the running state of the vehicle is urgent. It is determined whether or not the driving state is necessary, and when the driving state of the vehicle is a driving state that requires urgent driving motion control, an evaluation function set in advance for the plurality of driving motion control means is calculated. By distributing the target travel motion control amount of the entire vehicle to the plurality of travel motion control means, the target control amount of the plurality of travel motion control means is calculated, and the travel state of the vehicle is an emergency travel motion control. When the driving state is not necessary, a target control amount of a specific traveling motion control unit among the plurality of traveling motion control units is calculated based on the traveling state of the vehicle, and the specific traveling motion control is calculated. The amount of change in the physical quantity of the vehicle by the control of the specific travel motion control means is calculated based on the target control amount of the means, and the other amount of change in the target travel motion control amount of the entire vehicle and the amount of change in the physical quantity of the vehicle This is achieved by a vehicle travel control device that calculates a target control amount of the travel motion control means.

  According to the configuration of the first aspect, when the traveling state of the vehicle is a traveling state that requires urgent traveling motion control, the vehicle as a whole is calculated by calculating a preset evaluation function for the plurality of traveling motion control means. Since the target control amount of the plurality of travel motion control means is calculated by allocating the target travel motion control amount to the plurality of travel motion control means, all of the steering control means, the braking / driving force control means, and the ground load control means Is used to perform emergency running motion control, and thereby the running state of the vehicle can be reliably and effectively stabilized.

  Further, when the vehicle traveling state is not a traveling state requiring urgent traveling motion control, a target control amount of a specific traveling motion control unit among the plurality of traveling motion control units is calculated based on the traveling state of the vehicle. The change amount of the physical quantity of the vehicle by the control of the specific travel motion control means is calculated based on the target control amount of the specific travel motion control means, and based on the target travel motion control amount of the entire vehicle and the change amount of the physical quantity of the vehicle Since the target control amount of the other travel motion control means is calculated, the specific travel motion control means is preferentially controlled to stabilize the travel state of the vehicle, and the vehicle is controlled by the specific travel motion control means. The other travel motion control means can be supplementarily controlled based on the amount of change in the physical quantity of the vehicle and the target travel motion control amount of the entire vehicle. It can be controlled easily and reliably the vehicle dynamics control means as compared with the case of allocating all of the plurality of driving dynamics control means.

  According to the present invention, in order to effectively achieve the main problem described above, in the configuration of claim 1, the control means is a traveling state in which the traveling state of the vehicle requires emergency traveling motion control. Alternatively, it is determined whether or not the vehicle is in a traveling state in which the behavior of the vehicle may be deteriorated, and when the traveling state of the vehicle is a traveling state that requires emergency traveling motion control, the plurality of traveling motion control means By calculating the set first evaluation function, the target travel motion control amount of the entire vehicle is distributed to the plurality of travel motion control means, thereby calculating the target control amount of the plurality of travel motion control means, When the traveling state of the vehicle is not a traveling state that requires urgent traveling motion control but is a traveling state in which the behavior of the vehicle is likely to deteriorate, among the plurality of traveling motion control means based on the traveling state of the vehicle Calculating a target control amount of a specific travel motion control means, calculating a change amount of a physical quantity of the vehicle by control of the specific travel motion control means based on the target control amount of the specific travel motion control means, The target control amount of the other travel motion control means is calculated by calculating a second evaluation function preset for the other travel motion control means based on the overall target travel motion control amount and the amount of change in the physical quantity of the vehicle. When the vehicle traveling state is a traveling state that does not require urgent traveling motion control and there is no fear of deterioration of the behavior of the vehicle, the target control of the specific traveling motion control means is performed based on the traveling state of the vehicle. And a change amount of the physical quantity of the vehicle by the control of the specific travel motion control means is calculated based on the target control amount of the specific travel motion control means, and the target travel motion control of the entire vehicle is calculated. A target control amount of the other one of the travel motion control means is calculated based on the amount and the change amount of the physical quantity of the vehicle, the target travel motion control amount of the entire vehicle is reduced and corrected, and the target of the entire vehicle subjected to the reduction correction is calculated. A target control amount of the remaining travel motion control means is calculated based on the travel motion control amount (configuration of claim 2).

  According to the configuration of the second aspect, when the traveling state of the vehicle is a traveling state that requires emergency traveling motion control, the first evaluation function set in advance for the plurality of traveling motion control means is calculated. Since the target control amount of the plurality of travel motion control means is calculated by allocating the target travel motion control amount of the entire vehicle to the plurality of travel motion control means, the target travel motion control amount of the entire vehicle is It is distributed to all of the control means, and urgent running motion control is performed using all the control means, whereby the running state of the vehicle can be reliably and effectively stabilized.

  Further, when the vehicle traveling state is not a traveling state requiring urgent traveling motion control but is a traveling state in which the behavior of the vehicle may be deteriorated, a plurality of traveling motion control means are selected based on the traveling state of the vehicle. The target control amount of the specific travel motion control means is calculated, and the change amount of the physical quantity of the vehicle by the control of the specific travel motion control means is calculated based on the target control amount of the specific travel motion control means. The target control amount of the other travel motion control means is calculated by calculating a second evaluation function set in advance for the other travel motion control means based on the target travel motion control amount and the amount of change in the physical quantity of the vehicle. Therefore, priority is given to the specific traveling motion control means to control the vehicle to stabilize the traveling state, and the amount of change in the physical quantity of the vehicle and the overall view of the vehicle controlled by the specific traveling motion control means are controlled. Other travel motion control means can be controlled in an auxiliary manner based on the travel motion control amount, which makes it easier than calculating a preset evaluation function for all of the plurality of travel motion control means. And each traveling motion control means can be controlled reliably.

  In addition, when the vehicle traveling state is a traveling state that does not require urgent traveling motion control and there is no risk of deterioration of the behavior of the vehicle, a target control amount of a specific traveling motion control means is calculated based on the traveling state of the vehicle. The change amount of the physical quantity of the vehicle by the control of the specific travel motion control means is calculated based on the target control amount of the specific travel motion control means, and based on the target travel motion control amount of the entire vehicle and the change amount of the physical quantity of the vehicle The target control amount of the other one of the travel motion control means is calculated, the target travel motion control amount of the entire vehicle is reduced and corrected, and the remaining travel motion control is performed based on the corrected target travel motion control amount of the entire vehicle. Since the target control amount of the means is calculated, the priority of the control of each traveling motion control means is clarified without calculating the preset evaluation function for all of the plurality of traveling motion control means. Therefore, by calculating a preset evaluation function for all of the plurality of travel motion control means, the target travel motion control amount of the entire vehicle is simultaneously applied to all of the plurality of travel motion control means. Each traveling motion control means is controlled easily and reliably compared with the case where the target traveling motion control amount of the entire vehicle is distributed to each traveling motion control means by calculating a plurality of evaluation functions. be able to.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claim 1 or 2, the control means requires a running motion control in which the running state of the vehicle is urgent. When the vehicle is in a running state, the target load motion control amount of the entire vehicle is calculated by calculating a preset evaluation function for the ground load control means, the steering control means, and the braking / driving force control means. , By distributing to the steering control means and the braking / driving force control means, the target ground load of each wheel as the target control amount of the ground load control means, and the target slip of each wheel as the target control amount of the steering control means A target slip ratio of each wheel as a target control amount of the corner and the braking / driving force control means is calculated (configuration of claim 3).

  According to the third aspect of the present invention, when the traveling state of the vehicle is a traveling state that requires emergency traveling motion control, the ground load control means, the steering control means, and the braking / driving force control means are set in advance. By calculating the function, the target running motion control amount of the entire vehicle is distributed to the ground load control means, the steering control means, and the braking / driving force control means, thereby the target ground load of each wheel as the target control amount of the ground load control means. Since the target slip angle of each wheel as the target control amount of the steering control means and the target slip ratio of each wheel as the target control amount of the braking / driving force control means are calculated, the target travel motion control amount of the entire vehicle is grounded. It is optimally distributed to all of the load control means, steering control means, and braking / driving force control means to calculate the target ground load of each wheel, the target slip angle of each wheel, the target slip ratio of each wheel, and Load control means, the steering control means, control the effective driving dynamics control of an emergency by using all of the drive force control means may be reliably performed and effectively.

  According to the invention, in the configuration of any one of claims 1 to 3, the specific traveling motion control means is configured to be the ground load control means (configuration of claim 4).

  According to the configuration of the fourth aspect, since the specific traveling motion control means is the ground load control means, the ground load control means can be prioritized over the steering control means and the braking / driving force control means. Compared to the case where the control means or the braking / driving force control means is a specific traveling motion control means, the control amount of the steering control means and the braking / driving force control means is reduced, so that the wheels are independent of the steering operation by the driver. The vehicle can be stably driven while suppressing a sense of discomfort caused by steering or controlling the braking / driving force of each wheel regardless of the braking / driving operation by the driver.

  According to the present invention, in order to effectively achieve the above main problem, in the configuration of claim 4, the control means does not require emergency traveling motion control in the vehicle traveling state. When the vehicle is in a traveling state in which the behavior of the vehicle may be deteriorated, a target grounding load of each wheel is calculated as a target control amount of the grounding load control means based on the traveling state of the vehicle, and based on the target grounding load, The change amount of the physical quantity of the vehicle by the control of the ground load control means is calculated, and the steering control means and the braking / driving force control means are preliminarily determined based on the target travel motion control quantity of the entire vehicle and the change quantity of the physical quantity of the vehicle. By calculating the set evaluation function, the target slip angle of each wheel as the target control amount of the steering control means and the target slip ratio of each wheel as the target control amount of the braking / driving force control means Configured to calculate (Configuration of Claim 5).

  According to the fifth aspect of the present invention, when the traveling state of the vehicle does not require emergency traveling motion control but is a traveling state in which the behavior of the vehicle may be deteriorated, the ground load control is performed based on the traveling state of the vehicle. The target ground load of each wheel as the target control amount of the means is calculated, the change amount of the physical quantity of the vehicle by the control of the ground load control means is calculated based on the target ground load, and the target travel motion control amount of the entire vehicle and the vehicle The target slip angle of each wheel and the braking / driving force control means as the target control amount of the steering control means by calculating a preset evaluation function for the steering control means and the braking / driving force control means based on the change amount of the physical quantity of The target slip ratio of each wheel as the target control amount is calculated.

  Therefore, the ground load control means can be prioritized over the steering control means and the braking / driving force control means, and the steering is performed based on the target travel motion control amount of the entire vehicle and the change amount of the physical quantity of the vehicle by the control of the ground load control means. The target slip angle of each wheel as the target control amount of the control means and the target slip ratio of each wheel as the target control amount of the braking / driving force control means are optimally calculated, and the wheels are steered regardless of the steering operation by the driver. In addition, it is possible to reliably and effectively reduce the possibility of deterioration in the behavior of the vehicle while suppressing the uncomfortable feeling caused by controlling the braking / driving force of each wheel regardless of the braking / driving operation by the driver.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claim 4 or 5, the control means does not require an emergency running motion control when the vehicle is running. When the vehicle is in a travel state in which there is no risk of deterioration in the behavior of the vehicle, the target ground load of each wheel as a target control amount of the ground load control means is calculated based on the travel state of the vehicle, and based on the target ground load Each wheel as a target control amount of the steering control means is calculated based on the amount of change in the physical amount of the vehicle by the control of the ground load control means and based on the target travel motion control amount of the entire vehicle and the change amount of the physical quantity of the vehicle The target slip angle of the vehicle as a target control amount of the braking / driving force control means is calculated based on the target travel motion control amount of the vehicle as a whole. Wheel Configured to calculate the target slip rate (Configuration of Claim 6).

  According to the configuration of the sixth aspect, when the running state of the vehicle is a running state that does not require urgent running motion control and there is no risk of deterioration of the behavior of the vehicle, the ground load control means is based on the running state of the vehicle. The target ground load of each wheel as a target control amount of the vehicle is calculated, and the amount of change in the physical quantity of the vehicle by the control of the ground load control means is calculated based on the target ground load, and the target travel motion control amount of the entire vehicle and the vehicle The target slip angle of each wheel as the target control amount of the steering control means is calculated based on the change amount of the physical quantity, the target travel motion control amount of the entire vehicle is reduced and corrected, and the target travel motion control of the entire vehicle is reduced and corrected. Based on the amount, the target slip ratio of each wheel as the target control amount of the braking / driving force control means is calculated.

  Accordingly, not only can the control of the ground load control means be given top priority, but then the control of the steering control means can be prioritized to control the traveling motion of the vehicle, the target travel motion control amount of the entire vehicle and the ground load control means. The target slip angle of each wheel as the target control amount of the steering control means is optimally calculated based on the change amount of the physical quantity of the vehicle by the control of the vehicle, and is controlled based on the target travel motion control amount of the entire vehicle that is reduced and corrected. The target slip ratio of each wheel as the target control amount of the driving force control means can be easily calculated.

  According to the present invention, in order to effectively achieve the above main problem, the braking / driving force according to the configuration of claim 6 is based on the target travel motion control amount of the entire vehicle corrected for reduction. A target slip ratio of each wheel as a target control amount of the braking / driving force control unit is calculated by calculating a preset evaluation function for the control unit (configuration of claim 7).

  According to the configuration of the seventh aspect, the target control of the braking / driving force control unit is performed by calculating the evaluation function set in advance for the braking / driving force control unit based on the target travel motion control amount of the entire vehicle that has been corrected for reduction. Since the target slip ratio of each wheel as an amount is calculated, the target slip ratio of each wheel can be easily calculated based on the target travel motion control amount of the entire vehicle that has been corrected for reduction.

  According to the present invention, in order to effectively achieve the main problem described above, in the configuration according to any one of claims 2 to 7, the change amount of the physical quantity of the vehicle is a wheel according to the change of the ground load. It is comprised so that it may be the variation | change_quantity of the characteristic value of a tire (structure of Claim 8).

  According to the configuration of the above aspect 8, since the change amount of the physical quantity of the vehicle is the change amount of the characteristic value of the wheel tire accompanying the change of the contact load, the change amount of the characteristic value of the wheel tire accompanying the change of the contact load is determined. In consideration, the target slip angle of each wheel as the target control amount of the steering control means and the target slip ratio of each wheel as the target control amount of the braking / driving force control means can be optimally calculated.

  According to the present invention, in order to effectively achieve the above-mentioned main problems, in the configuration according to any one of the above-described claims, the control means is provided when the vehicle is in a spin state or a drift-out state. Alternatively, when there is a high possibility that the vehicle will collide with an obstacle, the vehicle traveling state is determined to be a traveling state requiring urgent traveling motion control (structure of claim 9).

  According to the configuration of the ninth aspect, when the vehicle is in a spin state or a drift-out state or when the vehicle is highly likely to collide with an obstacle, the traveling state of the vehicle requires emergency traveling motion control. Since it is determined that the vehicle is in a running state, when the vehicle is in a spin state or a drift-out state or when there is a high possibility that the vehicle will collide with an obstacle, the steering control means, braking / driving force control means, All of them are used to control the running motion of the vehicle, thereby reliably and effectively stabilizing the running state of the vehicle, and reliably and effectively reducing the possibility of the vehicle colliding with an obstacle. can do.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration according to any one of claims 2 to 9, the control means may cause the vehicle to be in a spin state or a drift-out state. When there is such a situation, the vehicle is judged to be in a running state in which there is a risk of deterioration in the behavior of the vehicle (configuration of claim 10).

  According to the configuration of claim 10, when the vehicle may be in a spin state or a drift-out state, it is determined that the vehicle traveling state is a traveling state in which the behavior of the vehicle may be deteriorated. When there is a possibility that the vehicle is in a spin state or a drift-out state, the vehicle is controlled by giving priority to the specific traveling motion control means to stabilize the traveling state of the vehicle, and by controlling the specific traveling motion control means. Based on the change amount of the physical quantity of the vehicle and the target travel motion control amount of the entire vehicle, other travel motion control means are controlled in an auxiliary manner, thereby calculating a preset evaluation function for all of the plurality of travel motion control means. Each traveling motion control means can be controlled easily and surely as compared to the case, and the possibility that the vehicle will be in a spin state or a drift-out state reliably and effectively. It can be reduced.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration according to any one of claims 1 to 10, the steering control means includes a front wheel steering control means and a rear wheel steering. The control means is configured to set the weight for the rear wheel in the evaluation function to 0 when the running state of the vehicle is a side slip state of the rear wheel. ).

  According to the structure of the above-mentioned claim 11, when the running state of the vehicle is the side slip state of the rear wheel, the weight for the rear wheel in the evaluation function is set to 0. It is possible to reliably prevent the side slip state of the rear wheel from further deteriorating due to a decrease in the lateral force of the rear wheel by setting the control amount to zero.

  According to the present invention, in order to effectively achieve the above main problems, in the configuration according to any one of claims 1 to 11, the steering control means includes a front wheel steering control means and a rear wheel steering. The control means is configured to set the weight for the front wheel in the evaluation function to 0 when the vehicle is running in the side slip state of the front wheel (structure of claim 12).

  According to the structure of the above-mentioned claim 12, when the running state of the vehicle is the side slip state of the front wheel, the weight for the front wheel in the evaluation function is set to 0, so the control amount for the front wheel of each control means is Thus, it is possible to reliably prevent the side slip state of the front wheels from further deteriorating due to the decrease in the lateral force of the front wheels.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration according to any one of claims 5 to 12, the control means is configured such that the driving operation amount of the driver and the traveling state of the vehicle. The target ground load of each wheel is calculated as the ground load of each wheel necessary to at least change the posture of the vehicle to the target posture (configuration of claim 13).

  According to the structure of the above-mentioned claim 13, the target ground load of each wheel is obtained as the ground load of each wheel necessary for setting the vehicle posture to the target posture based on the driving operation amount of the driver and the running state of the vehicle. Since the calculation is performed, the posture of the vehicle can be reliably controlled to the target posture corresponding to the driving operation amount of the driver and the traveling state of the vehicle.

[Preferred embodiment of problem solving means]
According to one preferred aspect of the present invention, in the configuration according to any one of the above claims 1 to 13, the means for calculating the target travel motion control amount of the entire vehicle is a vehicle operation based on the driver's vehicle driving operation amount. It is configured to calculate a target travel motion control amount for the entire vehicle based on a deviation between a target travel motion state amount of the vehicle corresponding to the target travel motion and an actual travel motion state amount of the vehicle based on the travel state of the vehicle ( Preferred embodiment 1).

  According to another preferred aspect of the present invention, in the configuration of the preferred aspect 1, the target running motion state quantity of the vehicle is a target longitudinal acceleration, a target lateral acceleration, and a target yaw rate of the vehicle, The travel motion control amount is configured to be a target longitudinal force, a target lateral force, and a target yaw moment of the vehicle (preferred aspect 2).

  According to another preferred aspect of the present invention, in the configuration of any one of the first to thirteenth aspects or the preferred aspect 1 or 2, the ground load control means is provided corresponding to each wheel, and is damped. The electromagnetic shock absorber is configured to generate a force and increase / decrease the ground contact load of the wheel (preferred aspect 3).

  According to another preferred aspect of the present invention, in any one of the first to thirteenth aspects or the preferred aspects 1 to 3, the steering control means controls the front wheels regardless of the steering operation by the driver. The front wheel steering control means can be steered and the rear wheel steering control means can steer the rear wheels irrespective of the steering operation by the driver (preferred aspect 4).

  According to another preferred aspect of the present invention, in any one of the first to thirteenth aspects or the preferred aspects 1 to 3, the steering control means controls the front wheels regardless of the steering operation by the driver. It is configured to be steerable (preferred aspect 5).

  According to another preferred aspect of the present invention, in any one of the first to thirteenth aspects and the preferred aspects 1 to 3, the steering control means is a rear wheel regardless of the steering operation by the driver. Is configured to be steerable (preferred aspect 6).

  According to another preferred aspect of the present invention, in the configuration according to any one of claims 2 to 13 or preferred aspects 1 to 6, the target travel motion control amount of the entire vehicle is a target longitudinal force of the vehicle, The target lateral force and the target yaw moment, and when the vehicle traveling state is a traveling state that does not require urgent traveling motion control and there is no fear of deterioration of the behavior of the vehicle, the reduction target of the entire vehicle is corrected. The target control amount of the remaining travel motion control means is calculated based on the target longitudinal force of the vehicle as the travel motion control amount (preferred aspect 7).

  According to another preferred embodiment of the present invention, in the structure according to any one of claims 3 to 13 or preferred embodiments 1 to 7, the control means is a ground load control means, a steering control means, a braking / driving force. By calculating a preset evaluation function for the control means, the target correction amount of the ground load of each wheel, the target correction amount of the slip angle of each wheel, and the target correction amount of the slip ratio of each wheel are calculated, Calculate the target ground load of each wheel as the sum of the ground load and its target correction amount, calculate the target slip angle of each wheel as the sum of the slip angle of each wheel and its target correction amount, and the slip rate of each wheel And the target correction amount are calculated so as to calculate the target slip ratio of each wheel (preferred mode 8).

  According to another preferred embodiment of the present invention, in any one of the above-described claims 4 to 13 or the preferred embodiments 1 to 7, the control means is preset with respect to the steering control means and the braking / driving force control means. The target correction amount of the slip angle of each wheel and the target correction amount of the slip ratio of each wheel are calculated by calculating the calculated evaluation function, and the target of each wheel is calculated as the sum of the slip angle of each wheel and the target correction amount. The slip angle is calculated, and the target slip ratio of each wheel is calculated as the sum of the slip ratio of each wheel and the target correction amount (preferred aspect 9).

  According to another preferred aspect of the present invention, in any one of the above-described claims 7 to 13 or the preferred aspects 1 to 7, the control means is an evaluation function preset for the braking / driving force control means. By calculating the target correction amount of the slip ratio of each wheel and calculating the target slip ratio of each wheel as the sum of the slip ratio of each wheel and the target correction amount (preferred aspect 10). .

  According to another preferred aspect of the present invention, in the configuration of any one of claims 8 to 13 or preferred aspects 1 to 10, the change amount of the characteristic value of the wheel tire is the change amount of the equivalent cornering power. (Preferred aspect 11).

According to another preferred aspect of the present invention, in any one of the preferred aspects 8 to 11, the target longitudinal force of the vehicle is Fxt, the target lateral force is Fyt, and the target yaw moment is Mzt. The slip angle of each wheel is αi, the slip ratio is κi, the longitudinal force is Fxi, the lateral force is Fyi, the yaw moment is Mzi, and Wx, Wy, and Wm are the vehicle longitudinal force, lateral force, and yaw, respectively. Weight for moment, Wk and Wdk as weight for slip rate κi and target correction amount δκti, Waf and Wdaf as weight for front wheel slip angle αf and target correction amount δαft, respectively, War and Wdar The weights for the slip angle αr of the rear wheel and the target correction amount δαrt are set as Wfzf and Wdfzf for the front wheels Fzfl and Fzfr and the target correction amounts δFztfl and δFztfr, respectively. Wfzr and Wdfzr are weights for the rear wheels Fzrl and Fzrr and their target correction amounts δFztrl and δFztrr, respectively, and Σ is the sum of the left and right front wheels and the left and right rear wheels. Fxt-ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ²
+ Warαr ² + Wdarδαtr ²
+ WfzfFzfl ² + WdfzfδFztfl ²
+ WfzfFzfr ² + WdfzfδFztfr ²
+ WfzrFzrl ² + WdfzrδFztrl ²
+ WfzrFzrr ² + WdfzrδFztrr ²
By calculating the evaluation function L1, the target correction amount δαft of the front wheel slip angle, the target correction amount δαrt of the rear wheel slip angle, the target correction amount δκti of each wheel slip rate, and the target correction of the ground load of each wheel It is arranged to calculate the quantity δFzti (preferred aspect 12).

According to another preferred embodiment of the present invention, in any one of the preferred embodiments 9 to 11, the control means has the following formula: L2 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ²
+ Warαr ² + Wdarδαtr ²
By calculating the evaluation function L2, the target correction amount δαft for the slip angle of the front wheels, the target correction amount δαrt for the slip angle of the rear wheels, and the target correction amount δκti for the slip ratio of each wheel are calculated ( Preferred embodiment 13).

According to another preferred embodiment of the present invention, in the preferred embodiment 10 or 11, the control means is represented by the following formula: L3 = Wx (Fxt−ΣFxi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
By calculating the evaluation function L3, the target correction amount δκti of the slip ratio of each wheel is calculated (preferred aspect 14).

The present invention will now be described in detail with reference to a few preferred embodiments with reference to the accompanying drawings.
[First embodiment]

  FIG. 1 is a schematic configuration diagram showing a front wheel steering control device, a rear wheel steering control device, and a braking force control device of a first embodiment of a vehicle travel control device according to the present invention, and FIG. 2 is a diagram of the first embodiment. It is a schematic block diagram which shows a driving force control apparatus and a ground load control apparatus.

  In FIG. 1, a travel control device 10 is mounted on a vehicle 12, and includes a front wheel steering control device 14, a rear wheel steering control device 16, a braking force control device 18, a driving force control device 20, a ground load. And a control device 22. The front wheel steering control device 14 and the rear wheel steering control device 16 constitute steering control means capable of steering the front wheels and the rear wheels irrespective of the steering operation of the driver, respectively, and the braking force control device 18 and the driving force. The control device 20 constitutes a braking / driving force control means capable of individually controlling the braking / driving force of each wheel independently of the driver's braking / driving operation in cooperation with each other.

  In FIG. 1, 24FL and 24FR indicate left and right front wheels, which are the steering wheels of the vehicle 12, respectively, and 24RL and 24RR indicate left and right rear wheels, respectively. The left and right front wheels 24FL and 24FR, which are steering wheels, are rotated via a rack bar 30 and tie rods 32L and 32R by a rack-and-pinion type power steering device 28 driven in response to an operation of the steering wheel 26 by a driver. Steered.

  The steering wheel 26 is drivingly connected to a pinion shaft 42 of the power steering device 28 via an upper steering shaft 34, a turning angle varying device 36, a lower steering shaft 38, and a universal joint 40. In the illustrated first embodiment, the turning angle varying device 36 is connected to the lower end of the upper steering shaft 34 on the housing 36A side, and connected to the upper end of the lower steering shaft 38 on the rotor 36B side. The auxiliary steering drive motor 44 is included.

  Thus, the turning angle varying device 36 rotationally drives the lower steering shaft 38 relative to the upper steering shaft 34 to drive auxiliary steering of the left and right front wheels 24FL and 24FR relative to the steering wheel 26. It functions as the main device of the front wheel steering control device 14 that can steer the front wheels regardless of the steering operation of the vehicle, and is controlled by the electronic control device 46 as will be described in detail later.

  On the other hand, the left and right rear wheels 24RL and 24RR are connected via tie rods 52L and 52R by the hydraulic or electric power steering device 50 of the rear wheel steering device 48 regardless of the steering of the left and right front wheels 24FL and 24FR by the driver. Steered. The rear wheel steering device 48 functions as a main device of the rear wheel steering control device 16 and is controlled by the electronic control device 46 as described in detail later.

  The power steering device 28 may be either a hydraulic power steering device or an electric power steering device, but the steering generated by the auxiliary wheel driving of the front wheels by the turning angle varying device 36 and transmitted to the steering wheel 26. A rack coaxial having, for example, an electric motor and a conversion mechanism such as a ball screw type that converts the rotational torque of the electric motor into a force in the reciprocating direction of the rack bar 30 so as to generate an auxiliary steering torque that reduces fluctuations in the reaction torque. The electric power steering device of the type is preferable.

  The braking force of each wheel is controlled by controlling the pressure Pi (i = fl, fr, rl, rr) in the wheel cylinders 58FL, 58FR, 58RL, 58RR, that is, the braking pressure, by the hydraulic circuit 56 of the braking device 54. It has become so. Although not shown in FIG. 1, the hydraulic circuit 56 includes an oil reservoir, an oil pump, various valve devices, and the like, and the braking pressure of each wheel cylinder is normally driven according to the depression operation of the brake pedal 60 by the driver. Are controlled by the master cylinder 62, and are individually controlled by the electronic control unit 46 as necessary.

  Thus, the braking device 54 functions as a main device of the braking force control device 18 capable of individually controlling the braking force of each wheel regardless of the driver's braking operation, and is controlled by the electronic control device 46 as described in detail later. Is done.

  In the illustrated embodiment, as shown in FIG. 2, the driving torque of the driving device 64 comprising, for example, an engine and a transmission is transmitted to the front wheel propeller shaft 68 and the rear wheel propeller shaft 70 by the center differential 66. . The driving torque transmitted to the front wheel propeller shaft 68 is transmitted to the left front wheel axle 74L and the right front wheel axle 74R by the front wheel differential 72, thereby rotating the left and right front wheels 24FL and 24FR. Further, the driving torque transmitted to the rear wheel propeller shaft 70 is transmitted to the left rear wheel axle 78L and the right rear wheel axle 78R by the rear wheel differential 76, whereby the left and right rear wheels 24RL and 24RR are rotationally driven.

  The center differential 66 is controlled by the electronic control unit 46 so that the transmission ratio of the drive torque to the front wheel propeller shaft 68 and the rear wheel propeller shaft 70 can be controlled. Further, the front wheel differential 72 is controlled by the electronic control unit 46, whereby the transmission ratio of the drive torque to the left front wheel axle 74L and the right front wheel axle 74R can be controlled, and the rear wheel differential 76 is controlled by the electronic control unit 46. As a result, the transmission ratio of the drive torque to the left rear wheel axle 78L and the right rear wheel axle 78R can be controlled.

  Thus, the drive device 64, the center differential 66, the front wheel differential 72, and the rear wheel differential 76 function as main devices of the drive control device 20 capable of individually controlling the driving force of each wheel regardless of the driving operation of the driver. As will be described in detail later, it is controlled by the electronic control unit 46.

  Further, as shown in FIG. 2, electromagnetic shock absorbers 80FL, 80FR, 80RL, and 80RR are provided on the suspensions of the left and right front wheels 24FL and 24FR and the left and right rear wheels 24RL and 24RR, respectively. The shock absorbers 80FL to 80RR have a known structure as described in, for example, Japanese Patent Application Laid-Open No. 2005-96587, and are controlled by the electronic control unit 46 to generate a damping force and It functions as a main device of the ground load control device 22 that increases or decreases the ground load.

  As shown in FIG. 3, the electronic control unit 46 includes a steering control electronic control unit 84 that controls the turning angle varying unit 36 and the power steering unit 50, and an assist torque control electronic control that controls the power steering unit 28. A braking force control electronic control device 88 for controlling the braking force of each wheel by controlling the hydraulic circuit 56 of the device 86, the control device 54, the driving torque of the driving device 64 and each differential (DFT) 66, 72, The electronic control device 90 for controlling the driving force for controlling 76, the electronic control device for grounding load control 92 for controlling the shock absorbers 80FL to 80RR, and the collision prevention control when the vehicle 12 may collide with an obstacle. Collision prevention control electronic control unit 94 and integrated control electronic control unit 9 for controlling these electronic control units 84 to 94 in an integrated manner 6 is included.

  Each of the electronic control devices 84 to 96 described above may include a CPU, a ROM, a RAM, and an input / output port device, which are composed of a microcomputer and a drive circuit connected to each other by a bidirectional common bus. The electronic control devices 84 to 96 send and receive signals indicating necessary information to each other through the CAN 98 as necessary.

  In the illustrated embodiment, as shown in FIGS. 1 and 3, the upper steering shaft 34 is provided with a steering angle sensor 100 for detecting the rotation angle of the upper steering shaft as the steering angle θ. The turning angle varying device 36 is provided with a rotation angle sensor 102 for detecting the relative rotation angle of the housing 36A and the rotor 36B as the relative rotation angle θre of the lower steering shaft 38 with respect to the upper steering shaft 34, and these sensors. Is supplied to the steering control electronic control unit 84 and the like via the CAN 98.

  Although not shown in FIGS. 1 and 2, a CCD camera 104 that captures the front of the vehicle 12 at the front of the vehicle 12 and a radar such as a millimeter wave radar that emits a millimeter wave as a detection wave to the front of the vehicle. A sensor 106 is provided. The CCD camera 104 outputs a signal indicating image information ahead of the vehicle 12 to the electronic control unit 94 for collision prevention control via the CAN 98, and the radar sensor 106 detects obstacles such as the vehicle ahead and road signs, A relative distance Lre and a relative speed Vre between the obstacle and the vehicle 12 are detected, and signals indicating the detected values are output to the collision prevention control electronic control device 94 or the like (for example, Japanese Patent Laid-Open No. 2005-2005). (See 31967).

  In a situation where it is determined that there is an obstacle ahead of the vehicle based on information from the CCD camera 104, the collision prevention control electronic control unit 94 divides the relative distance Lre by the relative speed Vre to predict the collision time. Ta (allowance time until collision) is calculated. When the collision prediction time Ta is equal to or less than the reference value Ta1 (a positive constant), the collision prevention control electronic control unit 94 determines that the vehicle is likely to collide with an obstacle and prevents the collision. The target deceleration Gxtc is calculated, and a signal indicating these is output to the integrated control electronic control device 96 and the like.

  Further, as shown in FIG. 3, the longitudinal acceleration sensor 108 for detecting the longitudinal acceleration Gx of the vehicle, the lateral acceleration sensor 110 for detecting the lateral acceleration Gy of the vehicle, the vehicle speed sensor 112 for detecting the vehicle speed V, and the yaw rate γ of the vehicle. As a yaw rate sensor 114 to detect, a pressure sensor 116 to detect the master cylinder pressure Pm, pressure sensors 118FL to 118RR to detect the braking pressure Pi (i = fl, fr, rl, rr) of each wheel, and the depression amount of the accelerator pedal 120 An accelerator opening sensor 122 for detecting the accelerator opening α of the vehicle and a torque sensor 124 for detecting the steering torque Ts are connected. A signal indicating the value detected by these sensors is also integratedly controlled via the CAN 98 as necessary. Is output to the electronic control device 96 and the like.

  The steering angle sensor 100, the lateral acceleration sensor 110, the yaw rate sensor 114, and the torque sensor 124 detect the steering angle θ, the lateral acceleration Gy, the yaw rate γ, and the steering torque Ts with positive values generated when the vehicle turns to the left. The sensor 102 detects the relative rotation angle θre with the case of relative turning of the left and right front wheels in the left turn direction as positive.

  The integrated control electronic control unit 96 calculates the target yaw rate γt of the vehicle, the target lateral acceleration Gyt of the vehicle, and the target longitudinal acceleration Gxt of the vehicle according to the flowchart shown in FIG. The target longitudinal force Fxt of the vehicle for setting the longitudinal acceleration Gx to the target longitudinal acceleration Gxt, the target lateral force Fyt of the vehicle for setting the lateral acceleration Gy of the vehicle to the target lateral acceleration Gyt, and the yaw rate γ of the vehicle to the target yaw rate γt. The target yaw moment Mzt of the vehicle is calculated as a target travel motion control amount for the entire vehicle.

  Further, the integrated control electronic control device 96 determines whether or not the vehicle running state is an unstable state such as a spin state or a drift-out state. When the vehicle traveling state is not an unstable state, It is determined whether or not the collision prevention control electronic control unit 94 has determined that the vehicle may collide with an obstacle. The integrated control electronic control unit 96 requires an emergency running motion control when the running state of the vehicle is unstable or when the vehicle may collide with an obstacle. When the vehicle is in a running state, the running motion control in an emergency is performed.

  In an emergency running motion control, the integrated control electronic control unit 96 follows the flowchart shown in FIG. 7 and, as will be described in detail later, the target longitudinal force Fxt, the target lateral force Fyt, the target yaw force of the vehicle. The moment Mzt, the slip angle αi of each wheel, the slip ratio κi, the longitudinal force Fxi, the lateral force Fyi, and the yaw moment Mzi (i = fl, fr, rl, rr) are calculated, and based on these, the front wheel steering control device 14, By calculating the first evaluation function L1 of the following equation 1 for the rear wheel steering control device 16, the braking force control device 18, the driving force control device 20, and the ground load control device 22, the front wheel Slip angle target correction amount δαft, rear wheel slip angle target correction amount δαrt, slip rate target correction amount δκti, each wheel ground load target correction amount δFzti (i = fl, fr, rl, rr) ) Is calculated.

L1 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ²
+ Warαr ² + Wdarδαtr ²
+ WfzfFzfl ² + WdfzfδFztfl ²
+ WfzfFzfr ² + WdfzfδFztfr ²
+ WfzrFzrl ² + WdfzrδFztrl ²
+ WfzrFzrr ² + WdfzrδFztrr ² (1)

  In the above equation 1, Wx, Wy, and Wm are weights for the longitudinal force, lateral force, and yaw moment of the vehicle, respectively, and Wk and Wdk are weights for the slip ratio κi and the target correction amount δκti, respectively. Waf and Wdaf are weights for the front wheel slip angle αf and its target correction amount δαft, respectively, and War and Wdar are weights for the rear wheel slip angle αr and its target correction amount δαrt, respectively. Wfzf and Wdfzf are weights for the front wheels Fzfl and Fzfr and their target correction amounts δFztfl and δFztfr, respectively. Wfzr and Wdfzr are weights for the rear wheels Fzrl and Fzrr and their target correction amounts δFztrl and δFztrr, respectively. Σ means the sum of the left and right front wheels and the left and right rear wheels.

  The integrated control electronic control unit 96 calculates the front wheel target slip angle αft as the sum of the average value αf of the slip angles αfl and αfr of the left and right front wheels and the target correction amount δαft of the front wheels, and slips the left and right rear wheels. The target slip angle αrt of the rear wheel is calculated as the sum of the average value αr of the angles αrl and αrr and the target correction amount δαrt of the rear wheel slip angle, and each of the sums of the slip ratio κi and the target correction amount δκti of the slip ratio is calculated. The wheel target slip ratio κti is calculated, and the target ground load Fzti (i = fl, fr, rl, rr) of each wheel is calculated as the sum of the ground load Fzi of each wheel and the target correction amount δFzti of the ground load.

  Further, the integrated control electronic control unit 96 deteriorates the vehicle running state into an unstable state such as a spin state or a drift-out state when the vehicle running state is not a running state that requires emergency running motion control. It is determined whether or not there is a fear, and whether or not there is a possibility of deterioration of the behavior of the vehicle. The electronic control device 96 for integrated control performs traveling motion control during metastable when there is a possibility of deterioration of the behavior of the vehicle, and performs normal traveling motion control when there is no possibility of deterioration of the behavior of the vehicle.

  In the metastable running motion control, the integrated control electronic control unit 96 attenuates the vibrations of the vehicle body and the wheels while ensuring good riding comfort of the vehicle according to the flowchart shown in FIG. Calculates the target ground load Fzti (i = fl, fr, rl, rr) of each wheel to suppress the change in the posture of the vehicle body due to acceleration / deceleration, turning, etc., and equivalent cornering power of each wheel based on the target ground load Fzti Cpi (i = fl, fr, rl, rr) is calculated.

  The integrated control electronic control unit 96 calculates the slip angle αi (i = fl, fr, rl, rr) and the slip ratio κi (i = fl, fr, rl, rr) of each wheel, and slips each wheel. Based on the angle αi, slip ratio κi, equivalent cornering power Cpi, etc., the longitudinal force Fxi and lateral force Fyi (i = fl, fr, rl, rr) of each wheel and the yaw moment Mzi (i = fl, fr, rl, rr) is calculated and the front wheel steering control device 14 and the rear wheel are calculated based on the target longitudinal force Fxt, the target lateral force Fyt, the target yaw moment Mzt of the vehicle, and the longitudinal force Fxi, lateral force Fyi, and yaw moment Mzi of each wheel. By calculating the second evaluation function L2 of the following equation 2 set in advance for the steering control device 16, the braking force control device 18, and the driving force control device 20, the target correction amount δαft of the front wheel slip angle is calculated as follows. Target correction amount δαrt of wheel slip angle, slip ratio target of each wheel To calculate the Seiryo δκti.

L2 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ²
+ Warαr ² + Wdarδαtr ² (2)

  In the normal running motion control, the integrated control electronic control unit 96 follows the flowchart shown in FIG. 5 in the same manner as in the case of the metastable running motion control. Fzti (i = fl, fr, rl, rr) is calculated, and the equivalent cornering power Cpi (i = fl, fr, rl, rr) of each wheel is calculated based on the target ground load Fzti.

Then, the integrated control electronic control unit 96 calculates the target slip angle βt and the target yaw rate γt of the vehicle based on the steering angle θ and the vehicle speed V, and the target cutting angle δft and the rear wheel of the front wheel based on the target slip angle βt and the target yaw rate γt. The target cutting angle δrt of the wheel is calculated. The integrated control electronic control unit 96 is used to change the lateral force Fy and yaw moment Mz of the vehicle to the target lateral force Fyt and the target yaw moment Mzt based on the target turning angle δft of the front wheels and the target turning angle δrt of the rear wheels, respectively. The target slip angle αft of the front wheel and the target slip angle αrt of the rear wheel are calculated as values equivalent to the target slip angle of the front wheel and the target slip angle of the rear wheel. Further, the integrated control electronic control device 96 is based on the slip rate κi (i = fl, fr, rl, rr) of each wheel, the longitudinal force Fxi, and the target longitudinal force Fxt of the vehicle, and the braking force control device 18 and the driving force control. By calculating the preset third evaluation function L3 of the following equation 3 for the device 20, the target correction amount δκti of the slip ratio of each wheel is calculated, and the sum of the slip ratio κi and the target correction amount δκti is calculated. As a result, the target slip ratio κti of each wheel is calculated.
L3 = Wx (Fxt−ΣFxi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² ) (3)

  When the electronic control device 96 for integrated control calculates the target slip angle αft of the front wheels, the target slip angle αrt of the rear wheels, the target slip ratio κti of each wheel, and the target ground load Fzti of each wheel, the signals indicating them are respectively steered. The control output is output to the control electronic control device 84, the braking force control electronic control device 88, the driving force control electronic control device 90, and the ground load control electronic control device 92.

  The steering control electronic control device 84 controls the turning angle variable device 36 and the power steering device 50 so that the front wheel slip angle αf and the rear wheel slip angle αr become the target slip angles αft and αrt, respectively, and the braking force control. The electronic control device 88 and the driving force control electronic control device 90 cooperate with each other to control the control device 54 and the driving device 64 so that the slip ratio κi of each wheel becomes the target slip ratio κti. The control device 92 controls the shock absorbers 80FL to 80RR so that the ground load Fzi of each wheel becomes the target ground load Fzti.

  The electronic control device 86 for assist torque control controls the power steering device 28 in a manner known in the art so as to reduce the steering burden on the driver, and the front wheel slip by the turning angle varying device 36. The power steering device 28 is controlled so as to reduce the change in the steering reaction force accompanying the control of the angle αf.

  Next, a main routine of vehicle travel control achieved by the integrated control electronic control unit 96 in the first embodiment will be described with reference to the flowchart shown in FIG. The control according to the flowchart shown in FIG. 4 is started by closing an ignition switch (not shown), and is repeatedly executed at predetermined time intervals.

  First, at step 410, a signal indicating the steering angle .theta. Is read, and at step 420, the vehicle target motion state quantity for making the vehicle run stably based on the vehicle speed V or the like is used. The yaw rate γt, the target lateral acceleration Gyt of the vehicle, and the target longitudinal acceleration Gxt of the vehicle are calculated.

For example, for the target yaw rate γt, the steering gear ratio input from the steering control electronic control unit 84 is N, the vehicle wheelbase is L, the stability factor is Kh, and the steering-yaw rate transient transfer function is H (s). The target lateral acceleration Gyt is calculated according to the following equation (4), and the yaw rate-lateral acceleration transient transfer function is G (s) and is calculated according to the following equation (5).
γt = θ · V / {N · L (1 + Kh · V ² )} H (s) (4)
Gyt = γt ・ V ・ G (s) (5)

The target longitudinal acceleration Gxt is the engine speed Ne, throttle opening degree Ta, transmission gear ratio Rd based on the transmission shift position Ps, master cylinder pressure Pm, collision prevention. On the basis of the target deceleration Gxtc for, the function F (Ne, Ta, Rd, Pm, Gxtc) for calculating the target longitudinal acceleration of the vehicle is calculated according to the following equation (6).
Gxt = F (Ne, Ta, Rd, Pm, Gxtc) (6)

  In step 430, the target longitudinal force Fxt of the vehicle for making the longitudinal acceleration Gx of the vehicle the target longitudinal acceleration Gxt, the target lateral force Fyt of the vehicle for making the lateral acceleration Gy of the vehicle the target lateral acceleration Gyt, A target yaw moment Mzt of the vehicle for setting the yaw rate γ to the target yaw rate γt is calculated as a target travel motion control amount for the entire vehicle for stably traveling the vehicle.

In particular, the target longitudinal force Fxt and the target lateral force Fyt of the vehicle are calculated according to the following equations 7 and 8, respectively, where the vehicle mass is Mv. The target yaw moment Mzt is the vehicle yaw inertia moment Iy, and the vehicle target yaw rate γt The differential value is calculated according to the following equation 9 with γtd.
Fxt = Mv · Gxt (7)
Fyt = Mv · Gyt (8)
Mzt = Iy · γtd (9)

  In step 440, for example, a deviation Δγ between the target yaw rate γt and the actual yaw rate γ of the vehicle is calculated, and whether the absolute value of the yaw rate deviation Δγ is greater than or equal to a reference value γ1 (positive constant) for behavior deterioration determination. It is determined whether or not the running state of the vehicle is an unstable state such as a spin state or a drift-out state by determining whether or not, and if an affirmative determination is made, the process proceeds to step 700 and a negative determination is made. If YES, go to step 450.

  In step 450, based on information input from the electronic control unit 94 for collision prevention control, there is an obstacle ahead in the traveling direction of the vehicle, and the predicted collision time Ta is less than the reference value Ta1 for determining the possibility of collision. It is determined whether or not there is a possibility of a collision. If an affirmative determination is made, the process proceeds to step 700. If a negative determination is made, the process proceeds to step 460.

  In step 460, for example, by determining whether or not the absolute value of the yaw rate deviation Δγ is equal to or greater than a reference value γ2 (a positive constant smaller than γ1) for determining the possibility of behavior deterioration, A determination is made as to whether there is a possibility of deterioration to an unstable state such as a drift-out state. If an affirmative determination is made, the process proceeds to step 600, and if a negative determination is made, the process proceeds to step 500.

  In step 500, vehicle running control during normal time is performed as described later in accordance with the routine shown in FIG. 5, and in step 600, the vehicle in a quasi-unstable state as described later in accordance with the routine shown in FIG. In step 700, the vehicle travel control in an emergency is performed as will be described later in accordance with the routine shown in FIG.

  Next, normal vehicle travel control in the first embodiment will be described with reference to the flowchart shown in FIG.

  First, in step 510, the vehicle body and wheel vibrations are attenuated and the change in the posture of the vehicle body due to acceleration / deceleration, turning, etc. is suppressed while ensuring good riding comfort of the vehicle according to the flowchart shown in FIG. The target ground load Fzti (i = fl, fr, rl, rr) of each wheel is calculated, and in step 520, a signal indicating the target ground load Fzti is output to the ground load control electronic control unit 92. When the ground load control electronic control unit 92 receives the signal indicating the target ground load Fzti, the ground load Fzi (i = fl, fr, rl, rr) of each wheel is electromagnetically controlled so as to become the corresponding target ground load Fzti. The shock absorbers 80FL to 80RR are controlled so that the ground load Fzi of each wheel is controlled.

  In step 530, the deviation of the ground load of each wheel as the deviation between the target ground load Fzti and the standard ground load of each wheel (for example, the value when the vehicle is stopped) Fz0i (i = fl, fr, rl, rr). ΔFzi (i = fl, fr, rl, rr) is calculated. In step 540, based on the ground load deviation ΔFzi, the amount of change ΔCpi (equivalent cornering power of each wheel) from a map not shown in the figure. i = fl, fr, rl, rr) is calculated, and the equivalent cornering power Cpi (i = fl, fr) of each wheel is calculated as the sum of the standard value Cp0i (positive constant) of the equivalent cornering power of each wheel and the amount of change ΔCpi. , Rl, rr) are calculated.

  In step 550, based on the steering angle θ, the vehicle speed V, and the equivalent cornering power Cpi of each wheel, the front wheel target for setting the lateral force Fy and yaw moment Mz of the vehicle to the target lateral force Fyt and target yaw moment Mzt, respectively. The front wheel target slip angle αft and the rear wheel target slip angle αrt are calculated as values equivalent to the slip angle and the rear wheel target slip angle.

For example, the target slip angle βt and the target yaw rate γt of the vehicle are calculated based on the steering angle θ and the vehicle speed V, and the distances in the vehicle front-rear direction between the center of gravity of the vehicle and the front wheel axle and the rear wheel axle are Lf and Lr, respectively. The average value of the equivalent cornering powers Cpfl and Cpfr of the front wheels is the equivalent cornering power Cpf of the front wheels, the average value of the equivalent cornering powers Cprl and Cprfr of the left and right rear wheels is the equivalent cornering power Cpr of the rear wheels, and s is the Laplace operator. Based on the target slip angle βt and the target yaw rate γt, the target cutting angle δft of the front wheels and the target cutting angle δrt of the rear wheels are calculated according to the following equation 10.

Then, based on the target cutting angle δft of the front wheel and the target cutting angle δrt of the rear wheel, the target slip angle αft of the front wheel and the target slip angle αrt of the rear wheel are calculated according to the following equations 11 and 12, respectively.

In step 570, the slip angle β of the vehicle body is estimated in a manner known in the art, and based on the target slip angle αft of the front wheels, the target slip angle αrt of the rear wheels, the slip angle β of the vehicle body, etc. The front wheel target rudder angle δft and the rear wheel target rudder angle δrt are calculated according to the following equations 13 and 14 corresponding to the above equations 11 and 12, and signals indicating the target rudder angles δft and δrt are calculated as the steering control electronic control unit 84. Is output. The target rudder angles δft and δrt may be values calculated according to the above equation 10.

  When the steering control electronic control unit 84 receives the signals indicating the target steering angles δft and δrt, the steering angle control amount Δδf of the front wheels and the rear wheels based on the target steering angles δft and δrt, the steering angle θ, the target steering gear ratio Rgt, and the like. A steering angle control amount Δδr of the steering wheel, the steering angle variable device 36 of the front wheel steering control device 14 and the power steering device 50 of the rear wheel steering control device 16 are controlled based on the steering angle control amounts Δδf and Δδr, Thus, the steering angle δf of the left and right front wheels and the steering angle δr of the left and right rear wheels are controlled to be the target steering angles δft and δrt, respectively.

  In step 575, the slip angle αi (i = fl, fr, rl, rr) of each wheel is calculated based on the information input from the steering control electronic control unit 84, and each wheel is determined based on the wheel speed Vwi of each wheel. The wheel slip ratio κi (i = fl, fr, rl, rr) is calculated. Further, based on the slip angle αi, the slip ratio κi, the equivalent cornering power Cpi, etc. of each wheel, for example, the longitudinal force Fxi of each wheel and the like in the manner known in the art as shown in Equations 31-40 of the above-mentioned Patent Document 1. The lateral force Fyi (i = fl, fr, rl, rr) is calculated, and the yaw moment Mzi (i = fl, fr, rl, rr) of the vehicle due to the longitudinal force Fxi and the lateral force Fyi is calculated.

  In step 580, the evaluation function L3 of the above equation 3 set in advance for the braking force control device 18 and the driving force control device 20 based on the slip ratio κi of each wheel, the longitudinal force Fxi, and the target longitudinal force Fxt of the vehicle. By performing the calculation, the target correction amount δκti (i = fl, fr, rl, rr) of the slip ratio of each wheel is calculated, and the target slip ratio of each wheel is calculated as the sum of the slip ratio κi and the target correction amount δκti. κti (i = fl, fr, rl, rr) is calculated.

  In step 590, the target braking / driving force Fxti (i = fl, fr, rl, rr) of each wheel is calculated based on the target slip ratio κti of each wheel, the wheel speed Vwi of each wheel, and the longitudinal acceleration Gx of the vehicle. The When the target longitudinal force Fxt of the vehicle is a driving force, the target braking force Fbti (i = fl, fr, rl, rr) of each wheel is set to 0, and the driving device is based on the target longitudinal force Fxt of the vehicle. 64 target outputs Fdt are calculated, and the target control amounts of the center differential 66, front wheel differential 72, and rear wheel differential 76 are calculated based on the target braking / driving force Fxti of each wheel.

  On the other hand, when the target longitudinal force Fxt of the vehicle is a braking force, the target output Fdt of the drive device 64 and the target control amount such as the center differential 66 are set to 0, and based on the target braking / driving force Fxti of each wheel. A target braking force Fbti for each wheel is calculated. A signal indicating the target control amount such as the target output Fdt and the center differential 66 is output to the driving force control electronic control device 90, and a signal indicating the target braking force Fbti of each wheel is output to the braking force control electronic control device 88. Is done.

  The driving force control electronic control unit 90 controls the output of the driving unit 64 based on the target output Fdt, and controls the center differential 66, the front wheel differential 72, and the rear wheel differential 76 based on the corresponding target control amounts. The power control electronic control device 88 controls the braking device 54 so that the braking force of each wheel becomes the corresponding target braking force Fbti, and thereby the braking / driving force Fxi of each wheel becomes the corresponding target braking / driving force Fxti. It is controlled as follows.

  Next, with reference to a flowchart shown in FIG. 6, the vehicle travel control in the semi-unstable state in the first embodiment will be described.

  Steps 610 to 645 are respectively performed in the same manner as in steps 510 to 540 and step 575 in the above-described normal vehicle travel control, and steps 670 and 690 are respectively performed in the above-described normal vehicle travel control. Steps 570 and 590 are performed in the same manner.

  In step 650, based on the target longitudinal force Fxt, the target lateral force Fyt, the target yaw moment Mzt of the vehicle, and the longitudinal force Fxi, lateral force Fyi, and yaw moment Mzi of each wheel, the front wheel steering controller 14 and the rear wheel By calculating the evaluation function L2 of the above-described formula 2 for the steering control device 16, the braking force control device 18, and the driving force control device 20, the front wheel slip angle target correction amount δαft, the rear wheel slip A target correction amount Δαrt for the corner and a target correction amount Δκti for the slip ratio of each wheel are calculated.

  The average value of the left and right front wheel slip angles αfl and αfr is the front wheel slip angle αf, the left and right rear wheel slip angles αrl and αrr is the rear wheel slip angle αr, and the average slip angle αf and the front wheel The target slip angle αft of the front wheel is calculated as the sum of the target correction amount δαft of the slip angle, and the target slip angle αrt of the rear wheel is calculated as the sum of the average value αr of the slip angle and the target correction amount δαrt of the rear wheel slip angle. The target slip ratio κti of each wheel is calculated as the sum of the slip ratio κi and the target correction amount Δκti of the slip ratio.

  Next, the vehicle travel control in an emergency in the first embodiment will be described with reference to the flowchart shown in FIG.

  First, in step 730, the ground contact load deviation ΔFzi of each wheel is calculated as the difference between the target ground load Fzti (i = fl, fr, rl, rr) of each wheel one cycle before and the standard ground load Fz0i. In step 740, the equivalent cornering power Cpi of each wheel is calculated in the same manner as in steps 540 and 640 described above. In step 745, the same procedure as in steps 575 and 645 described above is calculated. In this technical field, the slip angle αi of each wheel, the slip rate κi of each wheel, the longitudinal force Fxi and lateral force Fyi of each wheel, the yaw moment Mzi of the vehicle by the longitudinal force Fxi and lateral force Fyi are calculated. Then, the ground load Fzi (i = fl, fr, rl, rr) of each wheel is calculated in a known manner.

  In step 750, according to the flowchart shown in FIG. 9, the target longitudinal force Fxt, the target lateral force Fyt, the target yaw moment Mzt, the slip angle αi of each wheel, the slip rate κi, the longitudinal force Fxi, the lateral force Fyi, Based on the yaw moment Mzi, the target slip angle αft of the front wheels, the target slip angle αrt of the rear wheels, the target slip ratio κti of each wheel, and the target ground load Fzti of each wheel are calculated.

  When step 750 is completed, steps 760, 770, and 790 are sequentially executed in the same manner as in steps 520, 570, and 590 in the above-described normal vehicle traveling control, whereby the ground load Fzi, Control is performed so that the steering angle δf of the front wheels, the steering angle δr of the rear wheels, and the braking / driving force Fxi of each wheel have corresponding target values.

  Next, calculation control of the target ground load Fzti in step 510 described above will be described with reference to the flowchart shown in FIG.

First, at step 511, as shown in FIG. 11, the vertical speed Zbdi of the vehicle body 12B at the wheel position is calculated for each wheel by integration of the vertical acceleration Gzbi, and at the wheel position by integration of the vertical speed Zbdi. A vertical displacement amount Zbi of the vehicle body 12B is calculated. For each wheel 24, the vertical speed Zwdi of the wheel 24 is calculated by integrating the vertical acceleration Gzwi, and the vertical displacement amount Zwi of the wheel 24 is calculated by integrating the vertical speed Zwdi. Kbd, Kb, Kwd, Kw are the feedback gains for the vertical speed Zbdi, the vertical displacement Zbi, the vertical speed Zwdi, and the vertical displacement Zwi, respectively, and T is a transformer to give a good ride comfort according to the following equation 15. A grounding load feedback target control amount Fz1ti for attenuating the vibrations of the vehicle body and the wheel while ensuring is calculated. In FIG. 11, 80 indicates a shock absorber and 81 indicates a suspension spring.
Fz1ti = [Kbd Kwd Kb Kw] [Zbdi Zwdi Zbi Zwi] ^T (15)

  In step 512, it is known in the art from the target model of the vehicle based on the driving operation amount of the driver such as the steering angle θ, the accelerator opening degree Ta, the master cylinder pressure Pm, or the vehicle state amount such as the vehicle speed V. In this manner, the target motion state quantity in the three directions of the vehicle roll direction, pitch direction, and vertical direction, that is, the target roll quantity Rt, target pitch quantity Pt, and target heave quantity Ht of the vehicle are calculated.

  In step 513, the actual model of the vehicle based on the amount of driving operation of the driver or the vehicle's lateral acceleration Gy, longitudinal acceleration Gx, vertical displacement amount Zbi and vertical displacement amount Zwi at each wheel position. Further, the estimated motion state quantity in the three directions of the vehicle, that is, the estimated roll quantity Ra, the estimated pitch quantity Pa, and the estimated heave quantity Ha of the vehicle are calculated in a manner known in the art.

  In step 514, the deviations of the motion state quantities in the three directions, that is, the roll quantity deviation ΔR, the pitch quantity deviation ΔP, and the heave quantity deviation ΔH are calculated as deviations between each target motion state quantity and the estimated movement state quantity. Therefore, based on the roll amount deviation ΔR, the pitch amount deviation ΔP, and the heave amount deviation ΔH, in order to suppress the change in the posture of the vehicle body due to acceleration / deceleration, turning, etc. in a manner known in the art from the inverse model of the vehicle. The target control amounts in three directions of the vehicle, that is, the target anti-roll moment Mrt, the target anti-pitch moment Mpt, and the target anti-heave force Fzt are calculated.

  In step 516, the feedforward target control amount Fz2ti of the ground load of each wheel is calculated based on the target anti-roll moment Mrt, the target anti-pitch moment Mpt, and the target anti-heave force Fzt in a manner known in the art. In step 517, the target ground load Fzti of each wheel is calculated as the sum of the feedback target control amount Fz1ti and the feedforward target control amount Fz2ti.

  Next, calculation control of the target ground load Fzti in step 750 described above will be described with reference to the flowchart shown in FIG.

  First, in step 511, for example, the front wheel steering control device 14, the rear wheel steering control device 16, the braking force control device 18, and the driving force control device 20 are performed in the same manner as described in the above-mentioned Patent Document 1. , The control response frequency of the ground load control device 22 is obtained, and the values Wx, Wy, Wm, Wk, Wdk, Waf, Wdaf, War, Wdar, Wfzf, Wfzr, Wdfzf, and Wdfzr are calculated.

  In step 752, as in the case of step 450 described above, it is determined whether or not it is determined that the vehicle may collide with an obstacle ahead in the traveling direction, and an affirmative determination is made. Sometimes, the process proceeds to step 757a, and when a negative determination is made, the process proceeds to step 753.

  In step 753, the weight Wm is corrected to be increased and the weights Wx and Wy are corrected to be reduced so that the yaw moment of the vehicle is effectively controlled and the running state of the vehicle is effectively stabilized. . In this case, the reduction amount of the weight Wx is set to be smaller than the reduction amount of Wy so that the deceleration control of the vehicle is performed to some extent effectively.

  In step 754, it is determined whether or not the rear wheel is in a skid state, that is, whether or not the vehicle is in a spin state. If an affirmative determination is made, the process proceeds to step 755. When a negative determination is made, that is, when it is determined that the traveling state of the vehicle is in a drift-out state and the front wheels are in a skidding state, the routine proceeds to step 756.

  In step 755, the weights War and Wdar for calculating the steering angle control amount for the rear wheel in the above equation 1 are set to 0, and the weights Wfzr and Wdfzr for calculating the ground load control amount for the rear wheel are each 0. In step 756, the weights Waf and Wdaf for calculating the steering angle control amount for the front wheels in the above equation 1 are set to 0, and the weights Wfzf and Wdfzf for calculating the ground load control amount for the front wheels are set to 0, respectively. Each is set to 0.

  In step 757a, the weight Wx is increased and corrected, and the weights Wy and Wm are adjusted so that the vehicle yaw moment control and the vehicle deceleration control are effectively performed to reduce the possibility of a vehicle collision. Is reduced and corrected. In this case, the reduction amount of the weight Wm is set smaller than the reduction amount of Wy so that the collision avoidance of the vehicle by the steering operation of the driver is effectively performed.

  In step 757b, the steering-yaw rate transient transfer function H (s) and the yaw rate-lateral acceleration transient transfer function in the above equations 4 and 5 are used so that the collision avoidance of the vehicle by the steering operation of the driver is effectively performed. G (s) is corrected to increase.

  In step 757c, the weights Waf, Wdaf, War, and Wdar for calculating the steering angle control amount in the above equation 1 are increased and corrected so that the collision avoidance of the vehicle by the steering operation of the driver is effectively performed. The other weights, that is, the weights Wfzf, Wdfzf, Wfzr, and Wdfzr of the ground load control amount calculation are reduced and corrected.

  In step 758, based on the target longitudinal force Fxt, the target lateral force Fyt, the target yaw moment Mzt of the vehicle, the slip angle αi of each wheel, the slip ratio κi, the longitudinal force Fxi, the lateral force Fyi, and the yaw moment Mzi, By performing the calculation of the evaluation function L1 of the above-described formula 1 in advance for the steering control device 14, the rear wheel steering control device 16, the braking force control device 18, the driving force control device 20, and the ground load control device 22, Front wheel slip angle target correction amount δαft, rear wheel slip angle target correction amount δαrt, each wheel slip rate target correction amount δκti, each wheel ground load target correction amount δFzti (i = fl, fr, rl) , Rr) is calculated.

  In step 759, the target slip angle αft of the front wheel is calculated as the sum of the average value αf of the slip angles αfl and αfr of the left and right front wheels and the target correction amount δαft of the front wheel slip angle. The target slip angle αrt of the rear wheel is calculated as the sum of the average value αr of αrr and the target correction amount δαrt of the rear wheel slip angle, and the target of each wheel is calculated as the sum of the slip ratio κi and the target correction amount δκti of the slip ratio. The slip ratio κti is calculated, and the target ground load Fzti of each wheel is calculated as the sum of the ground load Fzi of each wheel and the target correction amount δFzti of the ground load.

As will be understood from the above description, in steps 420 and 430, the vehicle target longitudinal force Fxt and the target lateral force for making the vehicle traveling state the optimum traveling state in accordance with the driving operation amount of the driver and the vehicle state amount. The force Fyt and the target yaw moment Mzt are calculated, and in steps 440 to 700, the vehicle longitudinal force Fx, lateral force Fyt, and yaw moment Mz become the target longitudinal force Fxt, target lateral force Fyt, and target yaw moment Mzt, respectively. The electromagnetic shock absorbers 80FL to 80RR, the steering angle varying device 36 of the front wheel steering control device 14, and the power steering device 50 of the rear wheel steering control device 16, the driving device 64, and the braking device according to the traveling state of the vehicle 54 etc. are controlled appropriately.
Next, the operation of the first embodiment configured as described above will be described for (1) normal running, (2) quasi-unstable, and (3) emergency.

(1) During normal running of the vehicle During normal running when the running state of the vehicle is stable and the vehicle may not collide with an obstacle, a negative determination is made in steps 440 to 460 of the flowchart shown in FIG. The travel control during normal travel of the vehicle is performed according to the flowchart shown in FIG.

  That is, in step 511, the feedback target control amount Fz1ti of the ground load for attenuating the vibrations of the vehicle body and the wheels while ensuring good riding comfort of the vehicle is calculated. In steps 512 to 516, acceleration / deceleration and turning The feedforward target control amount Fz2ti of the ground load for suppressing the change in the posture of the vehicle body due to the above is calculated, and in step 517, the target grounding of each wheel is obtained as the sum of the feedback target control amount Fz1ti and the feedforward target control amount Fz2ti. The load Fzti is calculated, and in step 520, the electromagnetic shock absorbers 80FL to 80RR are controlled so that the ground contact load Fzi of each wheel becomes the corresponding target ground load Fzti.

  In steps 530 and 540, the equivalent cornering power Cpi of each wheel is calculated based on the ground contact load of each wheel. In step 550, the target slip angle αft and the rear of the front wheel are calculated based on the equivalent cornering power Cpi of each wheel. The target slip angle αrt of the wheel is calculated, and in step 570, the steering angle δf of the left and right front wheels and the steering angle δr of the left and right rear wheels become the target steering angles δft and δrt for achieving the target slip angles αft and αrt, respectively. Thus, the turning angle varying device 36 and the power steering device 50 are controlled.

  In steps 575 and 580, the target slip of each wheel is calculated by calculating the evaluation function L3 of the above equation 3 based on the slip ratio κi, the longitudinal force Fxi, the lateral force Fyi, the yaw moment Mzi and the target longitudinal force Fxt of the vehicle. The rate κti (i = fl, fr, rl, rr) is calculated, and in step 590, the target braking / driving force Fxti of each wheel is calculated, and the longitudinal force Fx of the vehicle is calculated based on the target braking / driving force Fxti. The target output Fdt of the driving device 64 for setting the target longitudinal force Fxt, the target control amount of the center differential 66, etc., the target braking force Fbti of each wheel are calculated, and the braking / driving force Fxi of each wheel is converted into the target braking / driving force Fxti. Thus, the braking device 54 and the like are controlled.

(2) When quasi-unstable When there is no possibility that the vehicle will collide with an obstacle, but when the quasi-unstable state where the running state of the vehicle may become unstable, steps 440 and 450 of the flowchart shown in FIG. In step 460, an affirmative determination is made. Thus, according to the flowchart shown in FIG. 6, traveling control when the vehicle is quasi-unstable is performed.

  That is, Steps 610 to 645 are executed in the same manner as in Steps 510 to 540 and Step 575 in the above-described normal vehicle traveling control, so that in Step 650, the ground load Fzi of each wheel is set. The electromagnetic shock absorbers 80FL to 80RR are controlled so as to achieve the corresponding target ground load Fzti.

  In step 650, the target slip angle αft of the front wheels, the target slip angle αrt of the rear wheels, and the target slip ratio κti of each wheel are calculated by the calculation of the evaluation function L2 of Equation 2 above. Steps 670 and 690 are respectively performed in the same manner as in steps 570 and 590 in the above-described normal vehicle traveling control, whereby the steering angle δf of the left and right front wheels and the steering angle δr of the left and right rear wheels are respectively set as the target The steered angle varying device 36 and the power steering device 50 are controlled so as to achieve the target steering angles δft and δrt for achieving the slip angles αft and αrt, and the braking / driving force Fxi of each wheel becomes the target braking / driving force Fxti. Thus, the braking device 54 and the like are controlled.

(3) Emergency In the case of emergency driving of a vehicle in which the driving state of the vehicle is unstable or the vehicle may collide with an obstacle, an affirmative determination is made in step 440 or 450 of the flowchart shown in FIG. As a result, the vehicle travel control in an emergency is performed according to the flowchart shown in FIG.

  That is, in steps 730 and 740, the equivalent cornering power Cpi of each wheel is calculated based on the ground load Fzi of each wheel. In step 745, the slip of each wheel is performed in the same manner as in steps 575 and 645 described above. The yaw moment Mzi of the vehicle is calculated by the angle αi, the slip ratio κi of each wheel, the longitudinal force Fxi and lateral force Fyi of each wheel, and the longitudinal force Fxi and lateral force Fyi.

  In step 750, the target slip angle αft of the front wheels, the target slip angle αrt of the rear wheels, the target slip ratio κti of each wheel, and the target ground load Fzti of each wheel are calculated by calculating the evaluation function L1 of the above equation 1. In steps 760, 770, and 790, the same control as that in steps 520, 570, and 590 in the above-described normal vehicle traveling control is sequentially executed, whereby the ground load Fzi of each wheel, the front wheel The electromagnetic shock absorbers 80FL to 80RR, the turning angle variable device 36 and the power steering device 50, braking so that the steering angle δf, the steering angle δr of the rear wheels, and the braking / driving force Fxi of each wheel have corresponding target values. The device 54 and the like are controlled.

  Thus, according to the first embodiment shown in the drawing, when the vehicle traveling state is a traveling state requiring urgent traveling motion control, the front wheel steering control device 14 and the rear wheel steering control device as steering control means. 16. Calculate the first evaluation function L1 set in advance for the braking force control device 18 and the driving force control device 20 as the braking / driving force control means and the ground load control device 22 as the ground load control means. By distributing the target longitudinal force Fxt, the target lateral force Fyt, and the target yaw moment Mzt of the vehicle as the target travel motion control amount to all of the plurality of travel motion control means, the front wheel is set as the target control amount of all the travel motion control means. Target slip angle αft, rear wheel target slip angle αrt, target slip ratio κti of each wheel, and target ground load Fzti of each wheel.

  Therefore, when the vehicle is in an unstable traveling state or the vehicle may collide with an obstacle, the target traveling motion control amount of the entire vehicle is distributed to all of the plurality of traveling motion control means, An emergency running motion control is performed using all the control means, whereby the running state of the vehicle can be reliably and effectively stabilized.

  Further, when the vehicle is not in a driving state that requires urgent driving motion control but in a driving state in which the behavior of the vehicle may be deteriorated, the ground load control device 22 is set to one of a plurality of driving motion control means. As specific traveling motion control means, a target ground load Fzti, which is a target control amount of the ground load control device 22, is calculated based on the traveling state of the vehicle, and the vehicle is controlled by the ground load control device 22 based on the target ground load Fzti. The amount of change in the equivalent cornering power Cpi of each wheel is calculated as the amount of change in the physical quantity of the vehicle, and the front wheel steering, which is another running motion control means, is calculated based on the target running motion control amount of the entire vehicle and the equivalent cornering power Cpi of each wheel. A second evaluation function L2 set in advance for the control device 14, the rear wheel steering control device 16, the braking force control device 18, and the driving force control device 20 is calculated. Front wheel target slip angle Arufaft, the rear wheel target slip angle Arufart, the target slip ratio κti of each wheel is calculated which is a target control amount of the driving dynamics control means by.

  Accordingly, the control of the ground load control device 22 is prioritized to control the vehicle running state, and the change amount of the equivalent cornering power Cpi of each wheel and the target travel motion of the entire vehicle controlled by the ground load control device 22 are controlled. Based on the control amount, the front wheel steering control device 14, the rear wheel steering control device 16, the braking force control device 18, and the driving force control device 20 as other traveling motion control means can be supplementarily controlled. Thus, each traveling motion control means can be controlled easily and reliably as compared to the case where the preset evaluation function is calculated for all of the plurality of traveling motion control means.

  Further, when the vehicle traveling state is a traveling state that does not require urgent traveling motion control and there is no possibility of deterioration of the behavior of the vehicle, the target ground contact that is the target control amount of the ground load control device 22 based on the traveling state of the vehicle. The load Fzti is calculated, and the change amount of the equivalent cornering power Cpi of each wheel is calculated as the change amount of the physical quantity of the vehicle by the control of the contact load control device 22 based on the target contact load Fzti, and the target running motion control amount of the entire vehicle is calculated. The front wheel target slip angle αft and the rear wheel, which are target control amounts of the front wheel steering control device 14 and the rear wheel steering control device 16 as another traveling motion control means based on the equivalent cornering power Cpi of each wheel. The target longitudinal force Fxt of the vehicle, which is the target travel motion control amount of the entire vehicle, which is calculated and reduced and corrected, the slip ratio κi of each wheel, and the longitudinal force Fxi are calculated. Based on the above, the target slip ratio κti of each wheel, which is the target control amount of the braking force control device 18 and the driving force control device 20 as the remaining traveling motion control means, is calculated.

  Accordingly, not only can the control of the ground load control device 22 be given the highest priority, but then the control of the front wheel steering control device 14 and the rear wheel steering control device 16 can be given priority to control the running motion of the vehicle. The target slip of the front wheel as the target control amount of the front wheel steering control device 14 and the rear wheel steering control device 16 based on the total target running motion control amount and the change amount of the equivalent cornering power Cpi of each wheel by controlling the ground load. The angle αft and the rear wheel target slip angle αrt are optimally calculated, and the targets of the braking force control device 18 and the driving force control device 20 are based on the target longitudinal force Fxt of the vehicle, the slip ratio κi of each wheel, and the longitudinal force Fxi. The target slip ratio κti of each wheel as a control amount can be easily calculated.

  Further, according to the first embodiment shown in the figure, since the specific traveling motion control means is the ground load control device 22, the front wheel steering control device 14 and the rear wheel steering control device 16 as the steering control means and the braking / driving operation are performed. The control of the ground load control device 22 can be prioritized over the control of the braking force control device 18 and the driving force control device 20 as force control means, whereby the steering control means or the braking / driving force control means can perform a specific traveling motion. The steering control amount and the braking / driving force control amount are reduced as compared with the control means, and the wheels are steered regardless of the steering operation by the driver, or each wheel regardless of the braking / driving operation by the driver. The vehicle can be stably driven while suppressing a sense of incongruity due to the braking / driving force being controlled.

  Further, according to the first embodiment shown in the drawing, when the vehicle traveling state is not a traveling state requiring urgent traveling motion control, but the traveling state is likely to deteriorate the behavior of the vehicle, the target ground load Fzti The amount of change in the equivalent cornering power Cpi of each wheel is calculated as the amount of change in the physical quantity of the vehicle under the control of the ground load control device 22, and is based on the target running motion control amount of the entire vehicle and the equivalent cornering power Cpi of each wheel. By calculating the second evaluation function L2, the front wheel target slip angle αft, which is the target control amount of the front wheel steering control device 14, the rear wheel steering control device 16, the braking force control device 18, and the driving force control device 20, is calculated. Since the target slip angle αrt of the wheel and the target slip ratio κti of each wheel are calculated, the change of the equivalent cornering power Cpi of each wheel under the control of the ground load control device 22 is not taken into consideration. As compared with the case where the wheel is not connected, the target slip angle and the target slip ratio of each wheel can be accurately calculated, and the slip angle and the slip ratio of each wheel can be accurately controlled.

  Similarly, when the traveling state of the vehicle is a traveling state that does not require urgent traveling motion control and there is no possibility of deterioration of the behavior of the vehicle, the physical quantity of the vehicle by the control of the ground load control device 22 based on the target ground load Fzti. The amount of change in the equivalent cornering power Cpi of each wheel is calculated as the amount of change in the front wheel, and the target slip angle αft of the front wheel and the target slip angle of the rear wheel are calculated based on the target running motion control amount of the entire vehicle and the equivalent cornering power Cpi of each wheel. Since αrt is calculated, the target slip angle of each wheel is accurately calculated and the slip angle of each wheel is compared with the case where the change in the equivalent cornering power Cpi of each wheel under the control of the ground load control device 22 is not taken into consideration. Can be controlled accurately.

  Also, according to the first embodiment shown in the figure, when an affirmative determination is made at step 440, that is, when the vehicle is in a spin state or a drift-out state, or an affirmative determination is made at step 450. In this case, that is, when there is a high possibility that the vehicle will collide with an obstacle, the emergency running motion control is performed in step 700. Therefore, when the vehicle is in the spin state or the drift out state, the spin state or the drift out state is performed. Can reliably and effectively stabilize the traveling motion of the vehicle, and when the vehicle is highly likely to collide with an obstacle, the traveling motion of the vehicle is not deteriorated. Can be reliably and effectively decelerated to reliably and effectively reduce the possibility of the vehicle colliding with an obstacle.

  Further, according to the first embodiment shown in the figure, if an affirmative determination is made in step 460, that is, if there is a possibility that the vehicle will be in a spin state or a drift-out state, a quasi-anxiety is made in step 600. Since the regular running motion control is performed, it is possible to reliably and effectively reduce the possibility that the vehicle will be in the spin state or the drift-out state, and to continue the stable running motion of the vehicle.

  In particular, according to the first embodiment shown in the drawing, the front wheel steering control device 14 and the rear wheel steering control device 16 are provided as steering control means, and the slip angles of the front wheels and the rear wheels are controlled. Compared to the case where only one of the rear wheels is controlled, the vehicle traveling motion can be reliably and effectively controlled by controlling the steering angle of the wheels.

  Further, according to the first embodiment shown in the figure, when there is a high possibility that the vehicle will collide with an obstacle, when the vehicle is in a skidding state of the rear wheel, in step 754 of FIG. An affirmative determination is made, and in step 755, the weights War and Wdar of the rear wheel steering angle control amount calculation in the third evaluation function L3 are set to 0, and the rear wheel ground load control amount calculation is performed. Since the weights Wfzr and Wdfzr are set to 0 respectively, the steering angle control amount and the ground load control amount for the rear wheels are set to 0, thereby causing the lateral force of the rear wheels to decrease, thereby causing the rear wheels to slip. It is possible to reliably prevent the state from getting worse.

  Further, according to the first embodiment shown in the figure, when there is a high possibility that the vehicle will collide with an obstacle, when the vehicle is in a skidding state, the result is negative in step 754 of FIG. In step 756, the steering wheel control amount calculation weights Waf and Wdaf are each set to 0, and the front wheel contact load control amount calculation weights Wfzf and Wdfzf are each set to 0. Therefore, the steering angle control amount and the ground load control amount for the front wheels can be set to 0, thereby reliably preventing the side slip state of the front wheels from further deteriorating due to the decrease in the lateral force of the front wheels.

Further, according to the first embodiment shown in the figure, when there is a high possibility that the vehicle will collide with an obstacle, the running state of the vehicle is a skidding state of the rear wheel, and the weight War or the like for the rear wheel is 0. And when the vehicle is in a high risk of colliding with an obstacle, the vehicle is in a skidding state of the front wheels, and the weight Waf or the like for the front wheels is set to 0, In step 753, the weight Wm is corrected to increase, and the weights Wx and Wy are corrected to decrease. Therefore, the control of the yaw moment of the vehicle is more effective than when the weights are not corrected. This can be performed and the running state of the vehicle can be effectively stabilized.
[Second Example]

  FIG. 10 is a flowchart showing a main routine of vehicle travel control in the second embodiment of the vehicle travel control apparatus according to the present invention. In FIG. 10, the same steps as those shown in FIG. 4 are assigned the same step numbers as those shown in FIG.

  In these two embodiments, if a negative determination is made in step 450, the process proceeds directly to step 500. Therefore, the determination in step 460 and the control in step 600 in the first embodiment are not performed. The other steps are executed in the same manner as in the first embodiment described above.

  Therefore, according to the two embodiments shown in the drawings, during normal driving in which the driving state of the vehicle is stable and there is no possibility of the vehicle colliding with an obstacle, steps 440 to 460 in the flowchart shown in FIG. A negative determination is made, whereby travel control during normal travel of the vehicle is performed in the same manner as in “(1) During normal travel of the vehicle” in the first embodiment.

  Further, when the vehicle is in an unstable traveling state or the vehicle is likely to collide with an obstacle, an affirmative determination is made in step 440 or 450 of the flowchart shown in FIG. As a result, the vehicle travel control in an emergency is performed in the same manner as in “(3) Emergency” in the first embodiment.

  Therefore, according to the two embodiments shown in the drawings, (1) control during normal driving of the vehicle or (3) emergency control is performed in the above-described first embodiment, and (2) control during quasi-unstable is performed. Except for the fact that it is not performed, it is possible to obtain the same operational effects as in the case of the above-described first embodiment, and it is possible to simplify the traveling control of the vehicle as compared with the case of the above-described first embodiment.

  Although the present invention has been described in detail with reference to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

  For example, in each of the above-described embodiments, the front wheel steering control device 14 and the rear wheel steering control device 16 are provided as the steering means. However, the traveling control device of the present invention is the front wheel steering control device 14 or the rear wheel steering control device 14. The present invention may be applied to a vehicle having only one of the wheel steering control devices 16.

  In particular, when the travel control device of the present invention is applied to a vehicle having only the front wheel steering control device 14, only the target slip angle αft of the front wheels is calculated in steps 550, 650, and 750, and steps 575 and 645 are performed. , 745, only the slip angles αfl, αfr of the left and right front wheels are calculated. Further, the first evaluation function L1 and the second evaluation function L2 are corrected as shown in the following equations 16 and 17, respectively.

L1 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ²
+ WfzfFzfl ² + WdfzfδFztfl ²
+ WfzfFzfr ² + WdfzfδFztfr ²
+ WfzrFzrl ² + WdfzrδFztrl ²
+ WfzrFzrr ² + WdfzrδFztrr ² (16)
L2 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Wafαf ² + Wdafδαtf ² (17)

  When the travel control device of the present invention is applied to a vehicle having only the rear wheel steering control device 16, only the target slip angle αrt of the rear wheels is calculated in steps 550, 650, 750, and step 575, In 645 and 745, only the slip angles αrl and αrr of the left and right rear wheels are calculated. Further, the first evaluation function L1 and the second evaluation function L2 are corrected as shown in the following equations 18 and 19, respectively.

L1 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Warαr ² + Wdarδαtr ²
+ WfzfFzfl ² + WdfzfδFztfl ²
+ WfzfFzfr ² + WdfzfδFztfr ²
+ WfzrFzrl ² + WdfzrδFztrl ²
+ WfzrFzrr ² + WdfzrδFztrr ² (18)

L2 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² )
+ Warαr ² + Wdarδαtr ² (19)

  In each of the above-described embodiments, the vehicle includes the collision prevention control electronic control device 94, the CCD camera 104, and the radar sensor 106 for performing the collision prevention control when there is a possibility of collision with the obstacle. However, the travel control device of the present invention may be applied to a vehicle that does not include a collision prevention device, in which case the determination in step 450 is omitted.

  Further, in each of the above-described embodiments, in steps 540, 640, and 740, the change amount ΔCpi of the equivalent cornering power of each wheel is calculated as the change amount of the characteristic value of the wheel tire with the change of the ground load. The equivalent cornering power Cpi of each wheel is calculated as the sum of the standard value Cp0i of the equivalent cornering power of the wheel and the amount of change ΔCpi. In addition to the equivalent cornering power Cpi of each wheel, the change in ground load is also calculated. As a change amount of the characteristic value of the wheel tire due to the change, a change amount ΔKdi (i = fl, fr, rl, rr) of each wheel driving stiffness is calculated, and a standard value Kd0i (a positive constant) of the driving stiffness of each wheel is calculated. The driving stiffness Kdi (i = fl, fr, rl, rr) of each wheel is calculated as the sum of the change amount ΔKdi, and in steps 575, 645, 745, etc. Cornering power Cpi and longitudinal force Fxi on each wheel based on the driving stiffness Kdi, lateral force Fyi, may be modified such that the yaw moment Mzi is calculated.

  In each of the above-described embodiments, when the vehicle normally travels, the third evaluation function L3 of the above equation 3 is calculated in step 580, so that the target correction amount δκti of the slip ratio of each wheel is obtained. The target slip rate κti of each wheel is calculated as the sum of the slip rate κi and the target correction amount δκti, but each wheel is controlled by controlling the steering angle of each wheel based on the slip angle αi. The lateral force Fyi and the yaw moment Mzi are calculated, and based on the vehicle target lateral force Fyt and the target yaw moment Mzt, which are reduced and corrected by the sum ΣFyi of the lateral force Fyi and the sum ΣMzi of the yaw moment Mzi, respectively, By calculating the third evaluation function L3, the target correction amount δκti of the slip ratio of each wheel may be corrected so as to be calculated.

L3 = Wx (Fxt−ΣFxi) ²
+ Wy (Fyt-ΣFyi) ²
+ Wm (Mzt-ΣMzi) ²
+ Σ (Wkκi ² ) ² + Σ (Wdkδκti ² ) (20)

  In each of the above-described embodiments, the weights of the rear wheels and the front wheels are reduced to 0 in steps 755 and 756, respectively. These weights may be modified to be reduced to positive values other than 0, as long as they are smaller than the non-state values.

  In each of the above-described embodiments, the target ground load Fzti of each wheel is calculated in a specific manner in steps 511 to 517 during normal driving of the vehicle. The target ground load Fzti of each wheel is used in this technical field as long as it is a value for attenuating the vibration of the vehicle body and the wheel while ensuring the ride comfort and suppressing the posture change of the vehicle body due to acceleration / deceleration or turning. The calculation may be performed in any known manner.

  Further, in each of the above-described embodiments, the turning angle varying device 36 as the main device of the front wheel steering control device 14 rotates the lower steering shaft 38 relative to the upper steering shaft 34 to thereby provide the driver. The left and right front wheels 24FL and 24FR are automatically steered without depending on the steering operation of the rear wheel, and the rear wheel steering device 48 of the rear wheel steering control device 16 is controlled by the power steering device 50 to the left and right tie rods 52L. And 52R are driven to automatically steer the left and right rear wheels 24RL and 24RR. The front wheel steering control device 14 and the rear wheel steering control device 16 are independent of the driver's steering operation. As long as the wheel can be steered, any configuration known in the art may be used, such as a steering device of a type that expands and contracts a tie rod.

  In each of the above-described embodiments, the main device of the contact load control device 22 is the shock absorbers 80FL to 80RR. However, any configuration known in the art can be used as long as the wheel contact load can be controlled. For example, an active stabilizer device may be used.

1 is a schematic configuration diagram showing a front wheel steering control device, a rear wheel steering control device, and a braking force control device of a first embodiment of a vehicle travel control device according to the present invention; FIG. It is a schematic block diagram which shows the driving force control apparatus and grounding load control apparatus of a 1st Example. It is a block diagram which shows the control system in a 1st Example. 3 is a flowchart showing a main routine of vehicle travel control achieved by the integrated control electronic control unit in the first embodiment. 3 is a flowchart showing a normal vehicle travel control routine in the first embodiment. 3 is a flowchart showing a vehicle travel control routine during quasi-unstable in the first embodiment. It is a flowchart which shows the traveling control routine of the vehicle in emergency in a 1st Example. FIG. 6 is a flowchart showing a calculation control routine of a target ground load Fzti in step 510 of the flowchart shown in FIG. 5. It is a flowchart which shows the calculation control routine of the target ground load Fzti in step 750 of the flowchart shown by FIG. It is a flowchart which shows the main routine of the traveling control of the vehicle achieved by the electronic controller for integrated control in a 2nd Example. It is explanatory drawing which shows the model of a vehicle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Driving control device, 14 ... Steering control device for front wheels, 16 ... Steering control device for rear wheels, 18 ... Braking force control device, 20 ... Driving force control device, 22 ... Ground load control device, 28 ... Power steering device, 36 ... Steering angle variable device, 46 ... Electronic control device, 48 ... Rear wheel steering control device, 50 ... Power steering device, 54 ... Braking device, 64 ... Drive device, 80FL-80RR ... Shock absorber, 84 ... For steering control Electronic control device 86 ... Electronic control device for assist torque control, 88 ... Electronic control device for braking force control, 90 ... Electronic control device for driving force control, 92 ... Electronic control device for ground load control, 94 ... For collision prevention control Electronic control device 96 ... Electronic control device for integrated control, 100 ... Steering angle sensor, 102 ... Rotation angle sensor, 104 ... CCD camera, 106 ... Radar sensor, 108 ... Front and rear Acceleration sensor, 110 ... Lateral acceleration sensor, 112 ... Vehicle speed sensor, 114 ... Yaw rate sensor, 116 ... Pressure sensor, 118FL-118RR ... Pressure sensor, 122 ... Accelerator opening sensor, 124 ... Torque sensor

Claims (13)

  A plurality of traveling motion control means for controlling the traveling motion of the vehicle in cooperation with each other by different actions, a means for calculating a target traveling motion state quantity for the vehicle to stably travel, and the traveling motion state of the vehicle A means for calculating a target travel motion control amount for the entire vehicle for setting the amount to the target travel motion state amount, and a target control for each of the plurality of travel motion control means based on the target travel motion control amount for the entire vehicle. And a plurality of travel motion control means for controlling the plurality of travel motion control means based on the corresponding target control amounts, respectively. The ground load control means for controlling the ground load, the steering control means capable of steering the wheels regardless of the steering operation by the driver, and the control of each wheel regardless of the braking / driving operation by the driver. Braking / driving force control means capable of individually controlling power, wherein the control means determines whether or not the traveling state of the vehicle is a traveling state that requires emergency traveling motion control, and the traveling state of the vehicle is When the traveling state requires urgent traveling motion control, the target traveling motion control amount of the entire vehicle is calculated by calculating a preset evaluation function for the plurality of traveling motion control means. The target control amount of the plurality of traveling motion control means is calculated by distributing the means, and when the traveling state of the vehicle is not a traveling state requiring urgent traveling motion control, the plurality of the plurality of traveling motion control means are calculated based on the traveling state of the vehicle. A target control amount of a specific travel motion control means is calculated, and the specific travel motion control means of the specific travel motion control means is calculated based on the target control amount of the specific travel motion control means. The amount of change in the physical quantity of the vehicle due to the control is calculated, and the target control amount of the other travel movement control means is calculated based on the target travel movement control quantity of the entire vehicle and the change amount of the physical quantity of the vehicle. Vehicle travel control device.   The control means determines whether the vehicle traveling state is a traveling state requiring emergency traveling motion control or a traveling state in which the vehicle behavior may be deteriorated, and the vehicle traveling state is an emergency traveling motion. When the driving state requires control, a target evaluation value of the vehicle as a whole is calculated by calculating a first evaluation function set in advance for the plurality of traveling motion control means. To calculate the target control amount of the plurality of running motion control means, and the running state of the vehicle is not a running state that requires emergency running motion control, but the running state of the vehicle may deteriorate. Is calculated based on the running state of the vehicle, the target control amount of the specific travel motion control means among the plurality of travel motion control means is calculated, and the target control amount of the specific travel motion control means is calculated. Accordingly, the amount of change in the physical quantity of the vehicle under the control of the specific running movement control means is calculated, and the other running movement control means is preliminarily determined based on the target running movement control amount of the entire vehicle and the amount of change in the physical quantity of the vehicle. By calculating the set second evaluation function, the target control amount of the other traveling motion control means is calculated, and the traveling state of the vehicle does not require urgent traveling motion control, and the behavior of the vehicle may be deteriorated. When there is no traveling state, a target control amount of the specific traveling motion control means is calculated based on the traveling state of the vehicle, and the specific traveling motion control means is calculated based on the target control amount of the specific traveling motion control means. The amount of change in the physical quantity of the vehicle due to the control of the vehicle is calculated, and the target amount of control of the other movement control means is calculated based on the target amount of movement control of the entire vehicle and the amount of change of the physical quantity of the vehicle The target travel motion control amount for the entire vehicle is reduced and corrected, and the target control amount for the remaining travel motion control means is calculated based on the target travel motion control amount for the entire vehicle subjected to the reduction correction. The vehicle travel control device according to claim 1.   The control means calculates a preset evaluation function for the ground load control means, the steering control means, and the braking / driving force control means when the running state of the vehicle is a traveling state that requires emergency traveling motion control. By distributing the target running motion control amount of the entire vehicle to the ground load control means, the steering control means, and the braking / driving force control means, the target of each wheel as the target control amount of the ground load control means The ground contact load, the target slip angle of each wheel as a target control amount of the steering control means, and the target slip ratio of each wheel as a target control amount of the braking / driving force control means are calculated. 3. A vehicle travel control apparatus according to 2.   4. The vehicle travel control apparatus according to claim 1, wherein the specific travel motion control means is the ground load control means.   When the vehicle traveling state does not require urgent traveling motion control but there is a possibility that the behavior of the vehicle may deteriorate, the target control amount of the ground load control unit is based on the traveling state of the vehicle. And calculating the amount of change in the physical quantity of the vehicle under the control of the ground load control means based on the target ground load, and calculating the target travel motion control amount of the entire vehicle and the vehicle By calculating a preset evaluation function for the steering control means and the braking / driving force control means based on the amount of change in physical quantity, the target slip angle of each wheel as the target control amount of the steering control means and the braking / driving are calculated. 5. The vehicle travel control apparatus according to claim 4, wherein a target slip ratio of each wheel is calculated as a target control amount of the force control means.   When the vehicle traveling state is a traveling state that does not require urgent traveling motion control and there is no fear of deterioration of the vehicle behavior, the control means determines the target control amount of the ground load control unit based on the traveling state of the vehicle. And calculating a change amount of a physical quantity of the vehicle by the control of the ground load control means on the basis of the target ground load, and calculating a target travel motion control quantity of the entire vehicle and a physical quantity of the vehicle. The target slip angle of each wheel as a target control amount of the steering control means is calculated based on the change amount of the steering control means, the target travel motion control amount of the entire vehicle is reduced and corrected, and the target travel of the entire vehicle subjected to the reduction correction is corrected. 6. The vehicle travel control apparatus according to claim 4, wherein a target slip ratio of each wheel as a target control amount of the braking / driving force control means is calculated based on a motion control amount.   A target of each wheel as a target control amount of the braking / driving force control means is calculated by calculating a preset evaluation function for the braking / driving force control means based on the reduction-corrected target traveling motion control amount of the entire vehicle. The vehicle travel control apparatus according to claim 6, wherein a slip ratio is calculated.   The vehicle travel control apparatus according to claim 2, wherein the change amount of the physical quantity of the vehicle is a change amount of the characteristic value of the wheel tire according to the change of the ground load.   The control means determines that the traveling state of the vehicle is a traveling state requiring emergency traveling motion control when the vehicle is in a spin state or a drift-out state or when the vehicle is highly likely to collide with an obstacle. The vehicle travel control device according to claim 1, wherein the vehicle travel control device is a vehicle travel control device.   3. The control unit according to claim 2, wherein when the vehicle is likely to be in a spin state or a drift-out state, the vehicle traveling state is determined to be a traveling state in which the behavior of the vehicle may be deteriorated. The vehicle travel control device according to any one of claims 9 to 9.   The steering control means includes a front wheel steering control means and a rear wheel steering control means, and the control means is a weight for the rear wheel in the evaluation function when the vehicle is running in a side slip state. 11. The vehicle travel control device according to claim 1, wherein the vehicle travel control device is set to 0.   The steering control means comprises a front wheel steering control means and a rear wheel steering control means, and the control means sets the weight for the front wheels in the evaluation function to 0 when the vehicle is running in a skidding state. The vehicle travel control apparatus according to claim 1, wherein the vehicle travel control apparatus is set to   The control means calculates a target grounding load of each wheel as a grounding load of each wheel necessary to at least change the vehicle posture to the target posture based on the driving operation amount of the driver and the running state of the vehicle. The vehicle travel control device according to any one of claims 5 to 12.

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