JP2010188928A - Vehicle behavior controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle behavior controller improving characteristics of vehicle behavior and comfort by controlling damping force of suspension and yaw motion of a vehicle according to a road surface condition. <P>SOLUTION: The vehicle behavior controller includes: suspension devices interposed between a vehicle body of the vehicle, and front wheels and rear wheels, each having a damping force-variable mechanism; a first yaw motion adjustment means adjusting driving force of right and left wheels in at least one of the front and rear wheels; a second yaw motion adjustment means adjusting a differential limit degree between the wheels; and a control means controlling the first and second yaw motion adjustment means according to the condition of a road surface to control the yaw motion of the vehicle, and controlling the damping force-variable mechanisms to adjust the damping force of the damping force-variable mechanisms. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle behavior control apparatus capable of adjusting a turning motion of a vehicle and a damping force of a suspension.

  There is a vehicle including a suspension device equipped with a damping force variable shock absorber (attenuating force varying means) capable of switching a damping characteristic. There are Patent Documents 1 and 2 as suspension devices used in such vehicles. In Patent Document 1, both damping stability and riding comfort of a vehicle are achieved by changing a damping force characteristic according to a traveling condition such as a vehicle speed and a sprung speed of the vehicle. In Patent Document 2, the vertical behavior of the vehicle is detected by a detection means such as a sensor, and the damping force characteristic is switched by switching to a preset mode according to the detection result.

JP-A-8-58333 Japanese Patent Laid-Open No. 10-278529

In the conventional suspension device, the vehicle is switched to the preset damping force based on information such as the vertical behavior of the vehicle. There is. Conventional damping force switching is performed in response to changes in the spring of the vehicle, so the damping force does not change even when the road surface changes, and this is also the case where the vehicle behavior characteristics are not what the driver expects. It is a factor that ends up. Further, when changing the vehicle behavior characteristic according to the road surface condition, not only the change of the damping force characteristic of the suspension but also the relationship with the yaw motion of the vehicle is important.
An object of the present invention is to provide a vehicle behavior control device that improves vehicle behavior characteristics and riding comfort by controlling yaw motion and suspension damping force according to road surface conditions.

  In order to set the above object, in the present invention, the suspension device provided between the vehicle body and the front and rear wheels and provided with a damping force varying mechanism, and the left and right wheels in at least one of the front wheels or the rear wheels. First yaw motion adjusting means for adjusting the driving force of the vehicle, second yaw motion adjusting means for adjusting the degree of differential restriction between the front and rear wheels, and first and second yaw motion according to the road surface condition Control means for controlling the yaw motion of the vehicle by controlling the adjusting means, and control means for controlling the damping force variable mechanism to adjust the damping force of the damping force variable mechanism.

  In the present invention, when the vehicle has road surface mode selection means for selecting the road surface condition by the driver, the control means controls the first and second yaw motion adjustments based on the road surface condition selected by the road surface mode selection unit. The control unit controls the yaw motion of the vehicle and the damping force variable mechanism to adjust the damping force.

  In the present invention, when the vehicle behavior detecting means for detecting information correlating with the behavior of the vehicle is further provided, the control means is the road surface condition when the detection value by the vehicle behavior detecting means is within a preset control region. When the first and second yaw motion adjusting means and the damping force variable mechanism are controlled based on the road surface condition selected by the mode selecting means, and the detection value by the vehicle behavior detecting means is outside the preset control region However, control is not performed on the first and second yaw motion adjusting means based on the road surface condition selected by the road surface condition mode selecting means, but control on the damping force variable mechanism is performed.

  In the present invention, in the case of having the damping force mode selection means for the driver to select a mode for arbitrarily changing the damping force of the damping force variable mechanism and the road surface condition mode selecting means for selecting the road surface condition, the control means Based on the mode selected by the force mode selection means and the road condition selected by the road condition mode selection means, the first and second yaw movement adjusting means are controlled to control the yaw movement of the vehicle, and the damping The damping force is adjusted by controlling the force variable mechanism.

  In the present invention, when the vehicle behavior detecting means for detecting information correlating with the behavior of the vehicle is further provided, the control means is configured such that when the detection value by the vehicle behavior detecting means is within a preset control region, the road surface Control is performed on the first and second yaw movement adjusting means and the damping force variable mechanism based on the road surface condition selected by the situation mode selecting means, and the detection value by the vehicle behavior detecting means is outside the preset control region. In this case, the damping force variable mechanism is controlled based on the damping force mode selected by the damping force mode selection means.

  According to the present invention, the suspension device that is interposed between the vehicle body and the front wheels and the rear wheels and includes the damping force variable mechanism, and the first and the second wheels that adjust the driving force of the left and right wheels in at least one of the front wheels and the rear wheels. 1 yaw motion adjusting means, second yaw motion adjusting means for adjusting the differential limit between the front and rear wheels, and the first and second yaw motion adjusting means according to the road surface condition to control the vehicle Control means for controlling the yaw motion of the vehicle and adjusting the damping force of the variable damping force mechanism by controlling the damping force variable mechanism, so that the yaw motion control and the damping of the suspension become the turning performance of the vehicle according to the road surface condition Because the force can be controlled, vehicle behavior characteristics and riding comfort are improved.

  According to the present invention, when the road surface condition mode selecting means for selecting the road surface condition is provided, the control means is configured to adjust the first and second yaw motion adjusting means based on the road surface condition selected by the road surface condition mode selecting means. To control the yaw motion of the vehicle and adjust the damping force by controlling the damping force variable mechanism, so that the driver can operate the road surface condition mode selection means according to the road surface condition and the turning performance of the vehicle. Since the yaw motion and damping force can be adjusted, the operability is good, and the vehicle behavior characteristics and riding comfort are improved.

  According to the present invention, the first and second yaw motion adjusting means based on the road surface condition selected by the road surface condition mode selecting means when the detection value by the vehicle behavior detecting means is within a preset control region; When the control of the damping force variable mechanism is executed and the detection value by the vehicle behavior detection means is outside the preset control region, the first and second yaw based on the road surface condition selected by the road surface condition mode selection means Since the control of the damping force variable mechanism is performed without controlling the motion adjusting means, the yaw motion and damping force, which are the turning performance of the vehicle, can be adjusted according to the road surface condition, and the vehicle behavior characteristics and riding comfort are further improved. .

  According to the present invention, when both the damping force mode selecting means for the driver to select the mode for arbitrarily changing the damping force of the damping force variable mechanism and the road surface condition mode selecting means for selecting the road surface condition are provided, the control is performed. The means controls the yaw movement of the vehicle by controlling the first and second yaw movement adjusting means based on the mode selected by the damping force mode selection means and the road surface condition selected by the road surface condition mode selection means. At the same time, since the damping force is adjusted by controlling the damping force variable mechanism, options for controlling the yaw motion and damping force are expanded, so that vehicle behavior characteristics and riding comfort are further improved.

  According to the present invention, when the detected value by the vehicle behavior detecting means is within a preset control region, the control means is configured to perform the first and second based on the road surface condition selected by the road surface condition mode selecting means. When the control for the yaw motion adjusting means and the damping force variable mechanism is executed, and the detection value by the vehicle behavior detecting means is outside the preset control range, it is based on the damping force mode selected by the damping force mode selecting means. Since the control for the damping force variable mechanism is performed, the yaw motion and the damping force that are the turning performance of the vehicle can be adjusted according to the road surface condition, and the vehicle behavior characteristics and the riding comfort are further improved.

1 is a schematic block configuration diagram showing an overall configuration of a vehicle behavior control device for a vehicle according to an embodiment of the present invention. It is a typical control block diagram which mainly shows the yaw turning control by a vehicle behavior control apparatus. It is a typical control block diagram which shows the content of the damping force control by a vehicle behavior control apparatus. 2 is a flowchart showing the contents of a first control mode by the vehicle behavior control apparatus shown in FIG. 2 is a flowchart showing the contents of a first control mode by the vehicle behavior control apparatus shown in FIG. It is a typical block block diagram which shows the whole structure of the vehicle behavior control apparatus of the vehicle which is other embodiment of this invention. It is a typical control block diagram which shows the content of the damping force control by a vehicle behavior control apparatus. It is a flowchart which shows the content of the 3rd control form by the vehicle behavior control apparatus shown in FIG. It is a flowchart which shows the content of the 4th control form by the vehicle behavior control apparatus shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The vehicle behavior control device shown in FIG. 1 is applied to a four-wheel drive vehicle 1. The output of the engine 2 mounted on the vehicle 1 is transmitted to the center differential 5 via the transmission 3 and the intermediate gear mechanism 4. The center differential 5 is provided with a front-rear wheel differential limiting mechanism 19 which will be described in detail later. The output of the center differential 5 is transmitted to the front left and right wheels 8L and 8R via a front differential (hereinafter referred to as front differential) 6 and axles 7L and 7R, respectively, and the front wheel side hypoid gear mechanism 9, propeller shaft 10 and rear wheels. It is transmitted to the left and right wheels 14L, 14R of the rear wheel 14 via the side hypoid gear mechanism 11, the rear differential (hereinafter referred to as rear differential) 12, and the axles 13L, 13R.

  The center differential 5 is composed of differential pinions 5A and 5B and side gears 5C and 5D that mesh with these differential pinions 5A and 5B. Torque input from the differential pinions 5A and 5B is transmitted to the front wheel 8 via one side gear 5C, and is transmitted to the rear wheel 14 via the propeller shaft 10 and the like via the other side gear 5D. Further, the center differential 5 allows the differential between the front wheel 8 and the rear wheel 14 so that the turning ability of the vehicle 1 is not hindered.

  In the center differential 5, the torque output from the engine 2 can be variably distributed to the front and rear wheels 8, 14 while the differential allowed between the front wheel 8 and the rear wheel 14 is variably limited. A front-rear wheel differential limiting mechanism 19 serving as a yaw motion adjusting means is provided.

  The front-rear wheel differential limiting mechanism 19 is configured by a wet hydraulic multi-plate clutch mechanism, and the differential between the front wheels 8 and the rear wheels 14 is performed according to the hydraulic pressure input from a drive system hydraulic unit (not shown). The degree of restriction can be adjusted, and the distribution of torque (driving force) transmitted to the front wheels 8 and the rear wheels 14 can be changed as appropriate. The hydraulic pressure input from the drive system hydraulic unit to the front / rear wheel differential limiting mechanism 19 is controlled by the center differential controller 32, which will be described later.

  Therefore, according to the front-rear wheel differential limiting mechanism 19, the traction performance of the vehicle 1 can be improved by adjusting the differential limiting degree between the front wheel 8 and the rear wheel 14, while the front wheel 8 and the rear wheel The differential with the wheel 14 is allowed, and the turning performance of the vehicle 1 can be improved.

  Next, the drive system on the rear wheel 14 side will be described. The rear wheel 14 is provided with a rear differential 12 that allows a differential between the left and right wheels 14L, 14R. A left-right wheel driving force moving mechanism 15 serving as a first yaw motion adjusting means capable of appropriately changing the difference in driving force transmitted to 14R is provided.

  A crown gear 16 that meshes with the pinion gear 10A at the rear end of the propeller shaft 10 is provided on the outer periphery of the case 12A in the rear differential 12, and a planetary gear mechanism 12B is provided inside the case 12A. The planetary gear mechanism 12B allows the differential between the left and right rear wheels 14L and 14R. Therefore, the torque input from the engine 2 to the crown gear 16 through the propeller shaft 10, the pinion gear 10A, etc. is allowed to be differential between the left rear wheel 14L and the right rear wheel 14R by the planetary gear mechanism 12B, while the both wheels 14L. , 14R.

  The driving force moving mechanism 15 between the left and right wheels includes a speed change mechanism 15A and a transmission capacity variable control type torque transmission mechanism 15B. The left wheel 14L and the right wheel are controlled by a command from the ECU 40 serving as control means mounted on the vehicle 1. The difference in driving force (i.e., torque) with respect to 14R can be changed as appropriate according to the traveling state of the vehicle. Of these, the speed change mechanism 15A increases or decreases the rotational speed of one of the left and right wheels (here, the left wheel 14L) and outputs it to the torque transmission mechanism 15B.

  This transmission capacity variable control type torque transmission mechanism 15B is a wet hydraulic multi-plate clutch mechanism capable of adjusting the transmission torque capacity in accordance with the hydraulic pressure input from the drive system hydraulic unit controlled by the ECU 40 as the control means. The left and right wheels 14L, 14L, 14B are utilized by utilizing the rotational speed difference between the rotational speed accelerated or decelerated by the transmission mechanism 15A and the rotational speed of the other of the left and right wheels (the right wheel 14R in this embodiment). By exchanging torque between 14R, the drive torque of one wheel can be increased or decreased, and the drive torque of the other wheel can be decreased or increased. Note that the planetary gear mechanism 12B, the transmission mechanism 15A, and the torque transmission mechanism 15B described above are well-known techniques, and thus detailed descriptions of these structures are omitted. The hydraulic pressure input from the drive system hydraulic unit to the left / right wheel driving force moving mechanism 15 is controlled by the rear differential controller 31. The contents of this control will be described later.

  Therefore, for example, when the vehicle 1 moves forward while turning right, a predetermined hydraulic pressure is input from the drive system hydraulic unit (not shown) to the left-right wheel driving force moving mechanism 15 of the rear differential 12 and the right rear wheel 14R. When the torque transmitted to is reduced, the right rear wheel 14R decelerates. At this time, the torque transmitted to the left rear wheel 14L is increased and the speed of the left rear wheel 14L is increased. Accordingly, it is possible to cause the vehicle 1 to generate a clockwise (clockwise) yaw moment.

  The drive system hydraulic unit (not shown) includes an accumulator, a motor pump that pressurizes the hydraulic oil in the accumulator to a predetermined pressure, a pressure sensor that monitors the hydraulic pressure pressurized by the motor pump, and a motor. An electromagnetic control valve that outputs the hydraulic pressure in the accumulator whose pressure has been adjusted by the pump while further adjusting the pressure, and a supply destination of the hydraulic pressure adjusted by this electromagnetic control valve is a predetermined oil chamber of the driving force moving mechanism 15 between the left and right wheels. (Not shown) and a direction switching valve for switching to a predetermined oil chamber (not shown) of the front-rear wheel differential limiting mechanism 19 are provided.

  Shock absorbers (damping force variable mechanisms) 36, 37, 38, and 39 serving as damping force varying mechanisms constituting the suspension device are provided between a vehicle body (not shown) constituting the vehicle 1 and the respective wheels. The vehicle 1 controls the vibration input state from the wheels 8L, 8R, 14L, 14R by the suspension to the vehicle 1 by changing the damping force characteristics of the shock absorbers 36, 37, 38, 39. 40 is controlled.

  The damping force control of the shock absorbers 36, 37, 38, 39 is performed by switching the opening of a variable orifice (not shown) provided in each of the shock absorbers 36, 37, 38, 39 by the damping force switching actuators 36a, 37a, 38a, 39a. Here, the damping force state can be switched in multiple steps or continuously.

  Each of the rear differential controllers 31 is an electronic control unit including an interface, a memory, a CPU, etc. (not shown), and the hydraulic pressure corresponding to the driving force difference between the rear left wheel 14L and the rear right wheel 14R and its output. A signal indicating the destination (driving force distribution signal) is transmitted to the driving system hydraulic unit, and the driving system hydraulic unit receiving the driving force difference signal appropriately controls the hydraulic pressure for the driving force moving mechanism 15 between the left and right wheels of the rear differential 12. Thus, the driving force difference between the rear left wheel 14L and the rear right wheel 14R is adjusted.

  Each of the center differential controllers 32 is an electronic control unit having an interface, a memory, a CPU and the like (not shown), and the hydraulic pressure corresponding to the degree of differential restriction between the front wheels 8 and the rear wheels 14 A signal indicating the output destination (front / rear wheel differential limiting signal) is transmitted to the drive system hydraulic unit, and the drive system hydraulic unit receiving the front / rear wheel differential limit signal receives the front / rear wheel differential limiting mechanism of the center differential 5. The degree of differential restriction between the front wheel 8 and the rear wheel 14 is adjusted by appropriately controlling the hydraulic pressure for the engine 19.

  The wheels 8L, 8R, 14L, and 14R of the vehicle 1 are provided with brake devices 21L, 21R, 22L, and 22R, respectively, and are independent of the brake devices 21L, 21R, 22L, and 22R, respectively. A braking system hydraulic unit for supplying hydraulic pressure is provided. The vehicle 1 is provided with a brake device controller 33. The brake device controller 33 is an electronic control unit provided with an interface, memory, CPU, etc., not shown, and includes four brake devices 21L, 21R, provided on each wheel 8L, 8R, 14L, 14R. A signal (brake increase / decrease signal) indicating the oil pressure to be increased / decreased with respect to each of 22L and 22R is transmitted to a brake system hydraulic unit (not shown), and the brake system hydraulic unit receiving the brake increase / decrease signal receives The hydraulic pressure input to each brake device 21L, 21R, 22L, 22R is appropriately controlled. The brake system hydraulic unit is provided with a motor pump for adjusting the brake fluid pressure, an electromagnetic control valve, and the like. From the brake device controller 33 for each of the brake devices 21L, 21R, 22L, and 22R. In response to this instruction, a predetermined hydraulic pressure is input. As described above, the rear differential controller 31 and the brake device controller 33 are connected to the ECU 40 via signal lines, respectively, and operate based on a control signal from the ECU 40.

  The damping force controller 34 controls the damping force control current value for the damping force switching actuators 36a, 37a, 38a, 39a.

  The ECU 40 is a computer provided with an interface, memory, CPU, etc., not shown, and includes a wheel speed sensor (vehicle speed detection means) 46, a brake switch 47, a G sensor (acceleration / deceleration detection means) 48, and a yaw rate sensor 49. The detection results of the vertical acceleration sensor 50, the accelerator position sensor (hereinafter referred to as APS) 51, and the steering angle sensor 52 can be read. Each of these sensors functions as vehicle behavior detection means. The ECU 40 is connected to a road surface condition mode selecting means 60 for selecting a road surface state in contact with each wheel. In the present embodiment, the road surface condition mode selection means 60 can select three road surface conditions. Reference numeral 61 is a switch for selecting a paved road, reference numeral 62 is a switch for selecting an unpaved road, and reference numeral 63 is a switch for selecting a snowy road.

  The ECU 40 includes a control yaw moment calculation unit 41, an understeer / oversteer determination unit (hereinafter referred to as “US / OS determination unit”) 42, a yaw motion control unit (yaw motion control means) as programs recorded in a memory (not shown). 43) and a suspension control unit 45. In addition, a yaw motion control map 44 and a damping force characteristic map 45A used by the yaw motion control unit 43 are recorded in this memory. Among these, the control yaw moment calculator 41 obtains a control yaw moment that is a yaw moment to be added in order for the vehicle 1 to turn at the turning radius intended by the driver.

  That is, as shown in FIG. 2, the control yaw moment calculator 41 calculates the theoretical target yaw rate (based on the rudder angle measured by the rudder angle sensor 52 and the vehicle speed detected by the wheel speed sensor 46. (Target yaw momentum correlation value) is calculated, and further, control for correcting the theoretical target yaw rate by comparing with the actual yaw rate measured by the yaw rate sensor 49, that is, feedback control based on the actual yaw rate is performed. By executing, the control yaw moment is calculated.

  The US / OS determination unit 42 determines the turning state of the vehicle 1 that is turning, and the control yaw moment obtained by the control yaw moment calculation unit 41 and the side of the vehicle 1 measured by the G sensor 48. Based on the acceleration in the direction, whether the vehicle 1 that is turning is in an understeer (US) state (understeer state) or is substantially free of understeer (US) and oversteer (OS) ( It is determined whether the vehicle is in a neutral steer state or is in a state in which oversteer (OS) is occurring (oversteer state).

  The yaw motion control unit 43 generates the yaw moment corresponding to the control yaw moment by controlling the rear differential controller 31, the center differential controller 32, and the brake device controller 33 according to the turning state of the vehicle 1. It is.

  That is, the yaw motion control unit 43 determines the control yaw moment obtained by the control yaw moment calculation unit 41, the determination result (turning state of the vehicle 1) by the US / OS determination unit 42, and the vehicle 1 measured by the G sensor 48. The control values for the rear differential controller 31, the center differential controller 32, and the brake device controller 33 are obtained by applying to the yaw motion control map 44 based on the acceleration in the longitudinal direction (longitudinal acceleration).

  The control value for the rear differential controller 31 is a hydraulic value of the left-right wheel driving force moving mechanism 15, and the control value for the brake device controller 33 is a hydraulic pressure increase / decrease value of each brake device 21L, 21R, 22L, 22R. Further, the control value for the center differential controller 32 is a value indicating the degree of differential regulation between the front and rear wheels by the front and rear wheel differential limiting mechanism 19 of the center differential 5, and more specifically, between the front and rear wheels. This is the hydraulic pressure value of the differential limiting mechanism 19.

  Next, the yaw motion control map 44 will be described. In the present embodiment, the yaw motion control map 44 includes three types for paved roads, unpaved roads, and snowy roads corresponding to road surface conditions. The basic configuration of these maps will be described. As shown in FIG. 2, the horizontal axis of the yaw motion control map 44 shows the turning state of the vehicle 1, that is, the control yaw moment obtained by the control yaw moment calculator 41. The degree of understeer (US) occurring in the vehicle 1 or the degree of oversteer (OS) obtained from the determination result by the US / OS determination unit 42 is defined. On the other hand, the absolute values of the control values for the rear differential controller 31, the center differential controller 32, and the brake device controller 33 are defined on the vertical axis.

  The yaw motion control map 44 mainly defines an oversteer suppression region 44A and an understeer suppression region 44B. In this oversteer suppression area 44A, a rear differential control area 44A1, a center differential control area 44A2, and a brake control area 44A3 are defined in order from the smallest control yaw moment. In the understeer suppression area 44B, a rear differential control area 44B1 and a brake control area 44B2 are defined in order from the smallest control yaw moment. The oversteer suppression region 44A and the understeer suppression region 44B are referred to as a yaw turning (S-AWC) control region, and a region that does not belong to the oversteer suppression region 44A and the understeer suppression region 44B is referred to as a non-control region 44C.

  In this embodiment, the ECU 40 is outside the yaw turning (S-AWC) control region when the understeer (US) and the oversteer (OS) are not generated (neutral steer state) in the US / OS determination unit 42. In the case of an understeer (US) or oversteer (OS) state, it is determined that it is within the yaw turning (S-AWC) control region. The ECU 40 selects the paved road yaw motion control map 44 when the switch 61 is selected, and selects the unpaved road yaw motion control map 44 when the switch 62 is selected. If the switch 63 is selected, the snow road yaw motion control map 44 is selected.

  When the yaw motion control unit 43 suppresses the yaw motion of the vehicle 1, that is, when the oversteer occurring in the vehicle 1 is suppressed, the yaw motion control unit 43 is first positioned on the turning center side of the left and right wheels 14 </ b> L and 14 </ b> R. The rear differential controller 31 is controlled so that the driving force of the wheel (ie, the turning inner wheel) is increased, and then the center differential controller 32 is controlled so as to increase the differential restriction between the front and rear wheels 8, 14. It is supposed to be. Further, the yaw motion control unit 43 is a case where oversteer occurring in the vehicle 1 </ b> A is suppressed, and performs the driving force control between the left and right wheels by the rear differential controller 31, and the front and rear wheels by the center differential controller 32. The brake device controller 33 is controlled so that the braking force of the outer turning wheel is larger than the braking force of the inner turning wheel only when the control yaw moment cannot be generated even after the differential limiting control is executed. It has become.

  The suspension control unit 45 uses the road surface condition selected by the road surface condition mode selecting means 60 and the input information from the wheel speed sensor (vehicle speed detecting means) 46, the brake switch 47, the vertical acceleration sensor 50, the APS 51, and the steering angle sensor 52. The damping force switching actuators 6a, 7a, 8a and 9a are calculated so as to select a damping force from the damping force characteristic map 45A shown in FIG.

  The damping force characteristic map 45A is a suspension damping force set according to the selected road surface condition. When the damping force on the paved road is “large”, it is “small” on a snowy road, and on a non-paved road. It is set to be “medium”. When the damping force is “Large”, the damping force control current value is “Small”, when the damping force is “Small”, the damping force control current value is “Large”, and when the damping force is “Middle”, the damping force The force control current value is set to be “medium”.

  That is, when the damping force control current value is small, the opening of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, and 9a is narrow, the damping force is high, and the damping force control current value is large. The opening of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a is set large and the damping force is set low.

  A control form of the vehicle behavior control apparatus having such a configuration will be described with reference to FIGS. In FIG. 4, the control means 40 reads the detection result by each sensor and the signal from the road surface mode selection means 60 in step S1. In step S2, the type of switch selected by the road surface condition mode selection means 60 is determined. When a paved road is selected, in step S3, the yaw turning control for the paved road is performed, and in step S4. Performs damping force control for paved roads.

  In step S3, a control yaw moment is calculated, it is determined whether oversteer or understeer is occurring, and the yaw motion control map 44 for a paved road selected according to the road surface condition is used according to the occurrence condition. The left and right wheel driving force moving mechanism 15, the brake devices 21L, 21R, 22L and 22R, and the front and rear wheel differential limiting mechanism 19 are controlled as appropriate.

  In step S4, “large” is selected from the damping force characteristic map shown in FIG. 4, and the damping force controller 34 controls the opening degree of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a to be narrowed. The damping force is set high.

  When the type of switch selected by the road surface condition mode selection means 60 in step S2 is a snowy road, the snowy road yaw turning control is performed in step S7, and the snowy road damping force control is performed in step S8.

  In step S7, a control yaw moment is calculated, it is determined whether oversteer or understeer is occurring, and the snowy road yaw motion control map 44 selected according to the road surface condition is used in accordance with the occurrence condition. The left and right wheel driving force moving mechanism 15, the brake devices 21L, 21R, 22L and 22R, and the front and rear wheel differential limiting mechanism 19 are controlled as appropriate.

  In step S8, “small” is selected from the damping force characteristic map shown in FIG. 4, and the damping force controller 34 controls the opening degree of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a to be increased. The damping force is set low.

  When the type of switch selected by the road surface condition mode selection means 60 in step S2 is an unpaved road, the yaw turning control of the unpaved road is performed in step S5, and the damping force control of the unpaved road is performed in step S8. .

  In step S5, a control yaw moment is calculated, whether or not oversteer or understeer is occurring is determined, and the unpaved road yaw motion control map 44 selected according to the road surface condition is used in accordance with the occurrence condition. The left and right wheel driving force moving mechanism 15, the brake devices 21L, 21R, 22L and 22R, and the front and rear wheel differential limiting mechanism 19 are controlled as appropriate.

  In step S6, "medium" is selected from the damping force characteristic map shown in FIG. 4, and the opening degree of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a is set to "medium" by the damping force controller 34. The damping force is set to the damping force between the paved road and the snowy road.

  As described above, the yaw motion of the vehicle 1 is controlled by controlling the driving force moving mechanism 15 between the left and right wheels, the differential limiting mechanism 19 between the front and rear wheels, and the brake devices 21L, 21R, 22L, and 22R according to the road surface condition. Since the damping force switching actuators 6a, 7a, 8a, and 9a are controlled to adjust the damping force of the shock absorbers 36 to 39, the yaw motion control and the suspension damping force control that become the turning performance of the vehicle 1 according to the road surface condition. Vehicle behavior characteristics and ride comfort are improved.

  Further, in this embodiment, since the driver selects and operates the road surface condition mode selection means 60, the yaw motion and the damping force that are the turning performance of the vehicle 1 can be adjusted according to the road surface condition, so that the operability is good and the vehicle behavior is improved. The characteristics and ride comfort are improved.

  FIG. 5 shows another form of control of the vehicle behavior control apparatus. In the control mode shown in FIG. 5, the left-right wheel driving force moving mechanism 15 based on the road surface condition selected by the road surface condition mode selecting means 60 when the detection value by the vehicle behavior detecting means is within a preset control region. The control for the front-rear wheel differential limiting mechanism 19, the brake devices 21L, 21R, 22L, 22R and the damping force switching actuators 6a, 7a, 8a, 9a is executed, and the detection values by the vehicle behavior detecting means are preset. When the vehicle is outside the control region, the right wheel driving force moving mechanism 15 and the front / rear wheel differential limiting mechanism 19 based on the road surface condition selected by the road surface mode selection means 60 and the brake devices 21L, 21R, 22L, 22R and damping force switching actuators 6a, 7a, 8a and 9a are not controlled, and normal damping is performed based on a general damping force characteristic map 45B as shown in FIG. It is obtained to perform the control. As contents of the flowchart, Step S11 and Steps S19 and S20 for determining whether or not the intervention area of the yaw turning control shown in Step S11 is added to the flowchart of FIG.

  In FIG. 5, in step S <b> 11, it is determined whether or not it is an intervention area for yaw turning control. For this determination, for example, the determination result of the US / OS determination unit 42 is used. Here, when understeer (US) or oversteer occurs in the turning vehicle, the process proceeds from step S12 to step S18, and yaw turning control and damping force control according to the road surface condition are executed. On the other hand, if understeer or oversteer has not occurred (neutral steer state), the process proceeds to step S19 because it is not an intervention area for yaw turning control, yaw turning control is canceled, and step S20 is proceeded to. Perform damping force control.

  The normal damping force control is to obtain a damping force from the input information from the wheel speed sensor (vehicle speed detecting means) 46, the brake switch 47, the vertical acceleration sensor 50, the APS 51, and the steering angle sensor 52, and generate this damping force. In addition, a damping force control current value for the damping force switching actuators 6a, 7a, 8a and 9a is calculated by the suspension control unit 45, and the damping force switching actuators 6a, 7a, 8a and 9a are operated by the damping force controller 34. . Examples of normal damping force control include well-known skyhook control that always keeps the sprung of the vehicle at a constant height, roll suppression control that suppresses the inclination of the vehicle body, and lateral G suppression control. At least one of these normal damping force controls may be set in the ECU 40.

  As described above, when the detected value by the vehicle behavior detecting means is within the preset control region (yaw turning control intervention region), the left-right wheel drive is performed based on the road surface condition selected by the road surface condition mode selecting means 60. The yaw movement of the vehicle 1 is controlled by controlling the force moving mechanism 15, the front-rear wheel differential limiting mechanism 19, and the brake devices 21L, 21R, 22L, and 22R, and the damping force switching actuators 6a, 7a, 8a, and 9a are controlled. The damping force of the shock absorbers 36 to 39 is adjusted by control, and when the detection value by the vehicle behavior detection means is outside the preset control area (yaw turning control intervention area), the road surface condition mode selection means selects Since the first and second yaw motion adjusting means and the damping force variable mechanism based on the road surface condition are not controlled, only the normal damping force control is executed. Yaw movement as a turning performance vehicle 1 and can adjust the damping force, it is possible to further improve the ride comfort and vehicle performance characteristics.

  FIG. 6 has both a damping force mode selection means 70 for the driver to select a mode for arbitrarily changing the damping forces of the shock absorbers 6, 7, 8, and 9 and a road surface condition mode selection means 60 for selecting the road surface condition. 1 shows a vehicle behavior control device. The contents of the yaw motion control control map 440 and the damping force characteristic map 450A are different from the vehicle behavior control device shown in FIG.

  The damping force mode selection means 70 is a switch for switching the damping force in two stages of a normal mode and a sports mode. Reference numeral 71 indicates a switch for switching to the normal mode, and reference numeral 72 indicates a switch for switching to the sports mode.

  The ECU 40A has the same function as that of the ECU 40, and based on the mode selected by the damping force mode selection means 70 and the road surface condition selected by the road surface condition mode selection means 60, The front / rear wheel differential limiting mechanism 19 and the brake devices 21L, 21R, 22L, and 22R are controlled to control the yaw motion of the vehicle 1, and the damping force switching actuators 6a, 7a, 8a, and 9a are controlled to control the damping force. It has a function to adjust.

  In the present embodiment, the yaw motion control control map 440 and the damping force characteristic map 45B correspond to the mode set by the damping force mode selection means 70 and the road surface condition selected by each switch of the road surface condition mode selection means 60. , Each with six maps. As shown in FIG. 7, the damping force characteristic map 45B is set so that the damping force is maximized in the case of a pavement road in the sport mode when the normal mode is used as a reference.

  A control mode of the vehicle behavior control apparatus having such a configuration will be described with reference to FIGS. In FIG. 8, the control means 40 </ b> A reads detection results from the sensors and signals from the road surface condition mode selection means 60 and the damping force mode selection means 70 in step S <b> 31. In step S32, the mode selected by the damping force mode selection means 70 is determined. If the normal mode is selected, the process proceeds to step S33. If the sport mode is selected instead of the normal mode, the step is performed. Proceed to S40.

  In step S33 and step S40, the type of switch selected by the road surface condition mode selection means 60 is determined. When the paved road is selected, the yaw turning control for the paved road is performed in steps S34 and S41, and the damping force control for the paved road is performed in steps S35 and S42. That is, in step S34 and step 41, the control yaw moment is calculated, it is determined whether oversteer or understeer is occurring, and the yaw motion control for the paved road selected according to the road surface condition according to the occurrence condition. Using the map 440, the left / right wheel driving force moving mechanism 15, the brake devices 21L, 21R, 22L, 22R, and the front / rear wheel differential limiting mechanism 19 are appropriately controlled.

  In step S35, the damping force “large” is selected from the map of FIG. 7, and in step S42, the damping force “large” is selected from the map of FIG. The damping force controller 34 controls the damping force switching actuators 6a, 7a, 8a, and 9a so that the opening of an orifice (not shown) is narrowed, and the damping force is set high.

  When the type of switch selected by the road surface condition mode selection means 60 in steps S33 and S40 is a snowy road, the yaw turning control for the snowy road is performed in steps S38 and S45, and the snow in the steps S39 and S46. Control the damping force for the road.

  In steps S38 and S45, a control yaw moment is calculated, it is determined whether oversteer or understeer is occurring, and a yaw motion control map 440 for a snowy road selected according to the road surface condition according to the occurrence condition. The right and left wheel driving force moving mechanism 15, the brake devices 21L, 21R, 22L, and 22R, and the front and rear wheel differential limiting mechanism 19 are controlled as appropriate.

  In steps S39 and S46, “small” is selected from the damping force characteristic map shown in FIG. 7, and the opening degree of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a and 9a is increased by the damping force controller 34. Thus, the damping force is set low.

  If the type of switch selected by the road surface condition mode selection means 60 in step S33 or step 40 is an unpaved road, yaw turning control of the unpaved road is performed in steps S36 and S43, and steps S37 and S44 are performed. The damping force control of the unpaved road is performed at

  In steps S36 and S43, a control yaw moment is calculated, it is determined whether oversteer or understeer is occurring, and the yaw motion control map of the unpaved road selected according to the road surface condition according to the occurrence condition. 440 is used to control the right / left wheel driving force moving mechanism 15, the brake devices 21 </ b> L, 21 </ b> R, 22 </ b> L, 22 </ b> R, and the front / rear wheel differential limiting mechanism 19 as appropriate.

  In steps S37 and S44, “medium” is selected from the damping force characteristic map shown in FIG. 7, and the opening of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a is set to “medium” by the damping force controller 34. The damping force is set to the damping force between the paved road and the snowy road.

  As described above, when both the damping force mode selection means 70 for the driver to select the mode for arbitrarily changing the damping force of the shock absorbers 36 to 39 and the road surface condition mode selection means 60 for selecting the road surface condition are provided, Based on the mode selected by the damping force mode selection means 70 and the road surface condition selected by the road surface condition mode selection means 60, the ECU 40A determines the left / right wheel driving force moving mechanism 15, the front / rear wheel differential limiting mechanism 19, and Since the brake devices 21L, 21R, 22L, 22R are controlled to control the yaw motion of the vehicle 1 and the damping force switching actuators 6a, 7a, 8a, 9a are controlled to adjust the damping forces of the shock absorbers 36 to 39. The options of yaw motion control and damping force control are expanded, and vehicle behavior characteristics and riding comfort can be further improved.

  FIG. 9 is a flowchart showing another control mode of the vehicle behavior control apparatus. In the control mode shown in FIG. 9, when the detected value by the vehicle behavior detecting means is within a preset control region, the driving force between the left and right wheels based on the road surface condition selected by the road surface condition mode selecting means 60. A control region in which the movement mechanism 15, the front-rear wheel differential limiting mechanism 19, the brake devices 21L, 21R, 22L, and 22R and the shock absorbers 36 to 39 are controlled, and the detection values by the vehicle behavior detection means are set in advance. In other cases, the shock absorbers 36 to 39 are controlled based on the damping force mode set by the damping force mode selection means 70.

  As contents of the flowchart, steps S21 to S23 are added to the flowchart of FIG. For this reason, the description up to step S10 to step S19 will be outlined, and the content of the added steps S21 to S23 will be mainly described.

  If the understeer (US) or oversteer has occurred in the turning vehicle from the determination result of the US / OS determination unit 42 in step S11 of FIG. 9, the process proceeds to step S12 to step S18 and the road surface condition is changed. The corresponding yaw turning control and damping force control are executed. On the other hand, if understeer or oversteer is not occurring (neutral steer state), the process proceeds to step S19 as not being an intervention area for yaw turning control, and yaw turning control is canceled, and the process proceeds to step S21.

  In step S21, the mode selected by the damping force mode selection means 70 is determined. If the normal mode is selected, the process proceeds to step S22 to perform damping force control for the normal mode, not the normal mode. If the sport mode is selected, the process proceeds to step S23 to perform the damping force control for the sport mode.

  In the normal mode damping force control, for example, the damping force controller 34 controls the damping force switching actuators 6a, 7a, 8a, and 9a so that the opening degree of the orifice (not shown) becomes “medium”, thereby reducing the damping for the sports mode. In the force control, the opening degree of the orifice (not shown) by the damping force switching actuators 6a, 7a, 8a, 9a is set to “large”.

  Thus, the control means 40A moves the driving force between the left and right wheels based on the road surface condition selected by the road surface condition mode selection means 60 when the detection value by the vehicle behavior detection means is within a preset control region. The control for the mechanism 15, the front-rear wheel differential limiting mechanism 19, the brake devices 21L, 21R, 22L, 22R and the shock absorbers 36 to 39 is executed, and the detection value by the vehicle behavior detecting means is outside the preset control range. In this case, since the damping force control for the shock absorbers 36 to 39 is performed based on the damping force mode selection means 70, the yaw motion and the damping force that are the turning performance of the vehicle 1 can be adjusted according to the road surface condition, and the vehicle behavior The characteristics and ride comfort are further improved.

  In each of the above forms, a paved road, an unpaved road, and a snowy road are set as options for the road surface condition. The damping force characteristic corresponding to the paved road is a high damping force characteristic that is assumed to travel mainly on a dry paved road. The damping force characteristic corresponding to the unpaved road is assumed to be traveling on a dirt road surface such as a wet road surface or sandy ground, and is set to a damping force characteristic lower than that of a paved road. The damping force characteristic corresponding to the snowy road is the characteristic with little change in grounding load with emphasis on the stability on the low mu road and the lowest damping force characteristic.

  In addition, when a snowy road is selected as the road surface condition, it may run with a studless tire. Therefore, when a snowy road is selected as the road surface condition, a change in grounding load occurs when the studless tire is mounted. It is good also as a damping force characteristic in which there is less.

DESCRIPTION OF SYMBOLS 1 Vehicle body 8L, 8R Front wheel 14L, 14R Rear wheel 15 1st yaw motion adjustment means 19 2nd yaw motion adjustment means 36-39 Damping force variable mechanism 40, 40A Control means 46-52 Vehicle behavior detection means 60 Road surface condition mode Selection means 70 Damping force mode selection means

Claims (5)

A suspension device interposed between the vehicle body and the front and rear wheels and provided with a variable damping force mechanism;
First yaw motion adjusting means for adjusting the driving force of the left and right wheels in at least one of the front wheels or the rear wheels;
A second yaw motion adjusting means for adjusting a differential limiting degree between the front and rear wheels;
Control for controlling the yaw motion of the vehicle by controlling the first and second yaw motion adjusting means according to the road surface condition, and controlling the damping force variable mechanism to adjust the damping force of the damping force variable mechanism And a vehicle attitude control device. Having a road surface mode selection means for a driver to select the road surface state;
The control means controls the yaw movement of the vehicle by controlling the first and second yaw movement adjusting means based on the road surface condition selected by the road condition mode selection means, and controls the damping force variable mechanism. The vehicle attitude control device according to claim 1, wherein the damping force is adjusted. Vehicle behavior detecting means for detecting information correlated with the behavior of the vehicle,
The control means includes first and second yaw movement adjustment means based on the road surface condition selected by the road surface condition mode selection means when the detection value by the vehicle behavior detection means is within a preset control region. And when the detected value by the vehicle behavior detecting means is out of a preset control region, the first and the first based on the road surface condition selected by the road surface condition mode selecting means are executed. 4. The vehicle attitude control device according to claim 1, wherein the second yaw motion adjusting means is not controlled but the damping force variable mechanism is controlled. Damping force mode selection means for the driver to select a mode for arbitrarily changing the damping force of the damping force variable mechanism;
Road surface condition mode selection means for selecting the road surface condition;
The control means controls the first and second yaw movement adjusting means to control the yaw movement of the vehicle based on the mode selected by the damping force mode selection means and the road surface condition selected by the road surface condition mode selection means. 3. The vehicle attitude control device according to claim 2, wherein the vehicle attitude control device adjusts the damping force by controlling the motion and controlling the damping force variable mechanism. Vehicle behavior detecting means for detecting information correlated with the behavior of the vehicle,
The control means adjusts the first and second yaw motion adjustments based on the road surface condition selected by the road surface condition mode selection means when the detection value by the vehicle behavior detection means is within a preset control region. If the detected value by the vehicle behavior detecting means is outside the preset control range, the control is performed based on the damping force mode selected by the damping force mode selecting means. The vehicle attitude control device according to claim 4, wherein the damping force variable mechanism is controlled.

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