JP5148679B2 - Control device and control method for damping force variable damper - Google Patents

Description

  The present invention relates to a control device for a damping force variable damper used for behavior control of an automobile and the like, and relates to a technique for suppressing a posture change of a vehicle body due to an input from a road surface.

  In order to suppress the change in the posture of the vehicle body due to input from the road surface or the like, a technique for controlling the damping force by a damping force variable damper provided for each wheel according to the motion state of the vehicle is known. . As a general control method, for each damper provided for each wheel, the motion state quantity of the vehicle body part near the damper is acquired, and the damping force of each damper is set / controlled based on the acquired motion state quantity. There is something to do.

  However, when the damping force is set independently for each damper, there is no correlation with the damping force of other dampers. There was a risk of lowering. As the damping force variable damper that adjusts the damping force by correlating the damping force for the front and rear or left and right wheels, a damping force adjustable hydraulic damper with a damping force adjustment mechanism is provided for the front and rear or left and right wheels, respectively. There has been proposed a configuration in which an oil chamber of a force-adjusting hydraulic damper is communicated by a pipe and a damping force is adjusted by a differential pressure between the oil chambers (see Patent Document 1).

JP 2002-127727 A

  However, in the damping force variable control device of Patent Document 1, the oil chambers of the damping force adjusting hydraulic damper are communicated with each other through an oil passage, and thus depend on the pressure difference between the oil chambers and the amount of movement of the oil liquid due to the pressure difference. The damping force is adjusted. For this reason, for example, the damping force adjusting hydraulic damper is controlled so that the left and right damping forces are different, or controlled so that the damping force increases when the damper stroke is in phase, or the damper stroke is in phase and input. It is not possible to control the damping force to be small when the sizes of are different. As a result, an appropriate damping force cannot be generated depending on the motion state or road surface state of the vehicle, and the posture change of the vehicle body may not be suppressed.

  The present invention has been made in view of such a background, can cope with various inputs, and compared with the one that controls the damping force independently for each damper provided for each wheel, It is an object of the present invention to provide a control device and a control method for a variable damping force damper capable of effectively suppressing a posture change of a vehicle body.

  In order to solve the above-mentioned problem, the first invention is installed in a four-wheel vehicle (V), and the damping force of the damper (6) disposed between the vehicle body (1) and each wheel (3) is variable. A control device (50) for a damping force variable damper to be controlled, which is provided in each vehicle body part (1a) adjacent to each damper and detects a movement state quantity detecting means (Vz) of the vehicle body part ( 13), a target damping force setting means (61) for setting a target damping force (Dt) of a damper adjacent to each motion state quantity detection means based on the detection result of each motion state quantity detection means, and one damper A correction value setting means (62) for setting a damping force correction value (Dc) for the vehicle body based on at least one of the movement state quantities of the vehicle body parts close to other dampers, and the above-mentioned based on the damping force correction value Target damping force compensation for correcting target damping force Characterized in that a means (63).

  According to this, the target damping force generated in one damper is set based on the motion state of the vehicle body part near the damper and is corrected in consideration of the motion state of the vehicle body part near the other damper. Correlation is created between each damper. Therefore, the effect of suppressing the change in the posture of the vehicle body can be improved as compared with the case where the damping force is controlled independently for each damper. In addition, since the target damping force can be appropriately corrected, it is possible to cope with various inputs.

  According to a second aspect of the present invention, in the damping force variable damper control device according to the first aspect of the invention, the correction value setting means sets the damping force correction value for one damper to the motion of a vehicle body part adjacent to another damper. It is set based on the average value (Vza) of the state quantity.

  According to this, the correction value of one damper is set based on the average value of the motion state quantities of the vehicle body parts that are close to the damper in the vehicle longitudinal direction, the left-right direction, and the diagonal direction with respect to the one damper. . Therefore, the target damping force is corrected in consideration of the motion state of the entire vehicle body, and as a result, the effect of suppressing the posture change of the vehicle body can be further improved.

  According to a third aspect of the present invention, in the damping force variable damper control device according to the first aspect of the invention, the damping force correction value for one damper is the damper among the motion state quantities of the vehicle body part adjacent to the other damper. Is set based on the one having the largest difference (Vzm) from the movement state quantity of the vehicle body part adjacent to the vehicle body.

  According to this, the correction value of one damper is set in consideration of the amount of motion state of the vehicle body part having the most different motion state with respect to the one damper. Therefore, the target damping force is corrected so as to increase within an appropriate range, and the effect of suppressing the change in posture of the vehicle body is improved.

  According to a fourth aspect of the present invention, in the damping force variable damper control device according to any one of the first to third aspects of the invention, the motion state quantity relates to vertical motion, and the target damping force correction means is When the movement direction (sign of Vz) of the vehicle body part adjacent to the one damper is different from the movement direction of the vehicle body part adjacent to the other damper, the absolute value of the target damping force is corrected to be increased. It is characterized by that.

  According to this, when the other damper has a reverse-phase input in the vertical direction, for example, by subtracting the correction value, the target damping force is corrected so that its absolute value becomes large. Therefore, the absolute value of the target damping force is larger than that in the conventional control method in which skyhook control or the like is performed for each damper. This is the result of correcting the target damping force in consideration of the fact that the other dampers have an input in reverse phase, that is, the change in the posture of the vehicle is large. Further improve.

  According to a fifth aspect of the present invention, in the damping force variable damper control device according to any one of the first to fourth aspects of the invention, the amount of motion state relates to vertical motion, and the target damping force correction means is The correction is performed only when the movement direction of the vehicle body part adjacent to the one damper is different from the movement direction of the vehicle body part adjacent to the other damper.

  According to this, when the other damper has an in-phase input in the vertical direction, the target damping force of the damper is set without considering the motion state of the vehicle body part close to the other damper. In-phase input to other dampers suppresses changes in the attitude of the vehicle. In this case, the base value becomes a necessary and sufficient value. The posture change can be suppressed.

  According to a sixth aspect of the present invention, in the damping force variable damper control device according to any one of the first to fifth aspects of the invention, the vehicle body part adjacent to one damper moves up and down at a first vertical speed, and the other The vehicle body part close to the damper moves up and down at a second vertical speed, and the target damping force setting means sets the target damping force of the one damper based on the first vertical speed, and the correction value The setting means sets the correction value of the one damper based on the second vertical speed.

  According to this, the target damping force of the damper is set in consideration of the vertical speed of the vehicle body part close to the damper and the vertical speed of the vehicle body part close to another damper. The vertical speed of the vehicle body part can be calculated from an acceleration sensor, for example, and can be easily realized by using a conventional device for a control device.

  The seventh invention is a method for variably controlling the damping force of the damping force variable damper (6) disposed between the vehicle body (1) and each wheel (3) in the four-wheel vehicle (V). The step of detecting the motion state quantity (Vz) of the vehicle body part (1a) adjacent to each damper, and the target damping force (generated by the damper adjacent to each vehicle body part) based on the detected motion state quantity of each vehicle body part ( Dt), a step of setting a damping force correction value (Dc) for one damper based on at least one of the motion state quantities of the vehicle body parts close to the other damper, and the damping force correction And a step of correcting the target damping force based on the value.

  According to this, similarly to the first invention, the damping force generated in one damper is set in consideration of the movement state of the vehicle body part near the damper and the movement state of the vehicle body part near the other damper. Therefore, the target damping force is set so that there is a correlation between the dampers. Therefore, the effect of suppressing the change in the posture of the vehicle body can be improved and various inputs can be handled.

  According to the present invention, the target damping force is set so that there is a correlation between the dampers. Accordingly, the effect of suppressing the change in the posture of the vehicle body can be improved and various inputs can be handled.

Schematic configuration diagram of a four-wheeled vehicle according to an embodiment Vertical sectional view of a damper according to an embodiment The block diagram which shows schematic structure of the damping-force control apparatus which concerns on embodiment. The block diagram which shows schematic structure of the skyhook calculation control part which concerns on embodiment The flowchart which shows the procedure of damping force control which concerns on embodiment Driving current map according to the embodiment The flowchart which shows the procedure of the skyhook calculation control processing which concerns on Example 1. FIG. 7 is a flowchart showing the procedure of skyhook calculation control processing according to the second embodiment. Flowchart showing the procedure of skyhook calculation control processing according to the third embodiment. Flowchart showing the procedure of skyhook calculation control processing according to the fourth embodiment. Comparison diagram of pitch rate by skyhook calculation control processing according to embodiments 3 and 4 Flowchart showing the procedure of skyhook calculation control processing according to the fifth embodiment. Comparison diagram of roll rate by skyhook calculation control processing according to embodiment 5 Flowchart showing the procedure of skyhook calculation control processing according to the sixth embodiment. Comparison diagram of roll rate by skyhook calculation control processing according to embodiment 6 Comparison diagram of pitch rate by skyhook calculation control processing according to embodiment 6

  Hereinafter, an embodiment in which the present invention is applied to a four-wheeled vehicle will be described in detail with reference to the drawings. In the description, for the four wheels 3 and the members arranged with respect to them, that is, the tire 2, the suspension 7, etc., subscripts indicating front, rear, left and right are attached to the reference numerals, respectively, for example, the wheel 3fl. (Front left), wheel 3fr (front right), wheel 3rl (rear left), wheel 3rr (rear right), and collectively referred to as wheel 3, for example.

  First, a schematic configuration of the automobile V according to the embodiment will be described with reference to FIG. As shown in the figure, a vehicle body 4 of an automobile (four-wheeled vehicle) V has wheels 3 with tires 2 mounted on the front, rear, left and right thereof. These wheels 3 are each provided with a suspension arm 4, a spring 5, and a variable damping force. It is suspended from the vehicle body 1 by a suspension 7 composed of a type damper (hereinafter simply referred to as a damper) 6 or the like. The automobile V includes an ECU (Electronic Control Unit) 8 used for various controls, a vehicle speed sensor 9 that detects vehicle speed, a lateral G sensor 10 that detects lateral acceleration, and a longitudinal G sensor 11 that detects longitudinal acceleration. A yaw rate sensor 12 for detecting the yaw rate is installed at an appropriate position of the vehicle body 1. Further, the automobile V has a vertical G sensor 13 (motion state amount detecting means) for detecting the vertical acceleration Gz of the damper base 1a (vehicle body part) constituting the upper part of the wheel house, and a stroke for detecting the stroke amount of the damper 6. A sensor 14 is provided for each of the wheels 3fl to 3frr.

  The ECU 8 includes a microcomputer, a ROM, a RAM, a peripheral circuit, an input / output interface, various drivers, and the like, and a damper for each wheel 3 via a communication line (CAN (Controller Area Network in this embodiment)). 6 and each sensor 9-14.

  FIG. 2 is a longitudinal sectional view of the damper 6 according to the embodiment. As shown in the figure, the damper 6 of the present embodiment is a monotube type (de carvone type), a cylindrical cylinder 22 filled with MRF (Magneto-Rheological Fluid), A piston rod 23 that slides in the axial direction with respect to the cylinder 22, a piston 26 that is attached to the tip of the piston rod 23 and divides the inside of the cylinder 22 into an upper oil chamber 24 and a lower oil chamber 25, and a lower portion of the cylinder 22 The main components are a free piston 28 defining a high-pressure gas chamber 27, a cover 29 for preventing dust from adhering to the piston rod 23 and the like, and a bump stop 30 for buffering at the time of full bound.

  The cylinder 22 is connected to the upper surface of the suspension arm 4 that is a wheel side member via a bolt 31 that is fitted into the eyepiece 22a at the lower end. Further, the piston rod 23 has a pair of upper and lower bushes 32 and a nut 33, and a stud 23a at the upper end thereof is connected to a damper base 1a which is a vehicle body side member.

  The piston 26 is provided with an annular communication passage 41 that allows the upper oil chamber 24 and the lower oil chamber 25 to communicate with each other, and an MLV coil 42 that is positioned inside the annular communication passage 41. When a current is supplied from the ECU 8 to the MLV coil 42, a magnetic field is applied to the MRF flowing through the annular communication path 41, and the ferromagnetic fine particles form a chain cluster. As a result, the apparent viscosity of the MRF passing through the annular communication passage 41 (hereinafter simply referred to as viscosity) increases, and the damping force in the extension direction and contraction direction of the damper 6 increases.

  FIG. 3 is a block diagram showing a schematic configuration of the damping force control device 50 according to the embodiment. As shown in the figure, the ECU 8 includes a damping force control device 50 that controls the damper 6. The damping force control device 50 includes the input interface 51 to which the above-described sensors 9 to 14 are connected, the roll moment, the pitch moment, the sprung speed, and the like obtained from the detection signals of the sensors 9 to 13. A damping force setting unit 52 that sets a target damping force, a driving current generation unit 53 that generates a driving current to each damper 6 (MLV coil 42) according to the target damping force input from the damping force setting unit 52, and a drive The output interface 54 outputs the drive current generated by the current generator 53 to each damper 6. The damping force setting unit 52 includes a skyhook calculation control unit 55 used for skyhook control, a roll calculation control unit 56 used for roll control, a pitch calculation control unit 57 used for pitch control, A sprung speed estimating unit (sprung speed estimating means) 58 for estimating a sprung speed at each wheel is accommodated.

  FIG. 4 is a block diagram showing a schematic configuration of the skyhook calculation control unit 55 according to the embodiment. As shown in the figure, the skyhook calculation control unit 55 includes target damping force setting units 61fl to 61rr provided for the respective wheels 3fl to 3rr, a damping force correction value setting unit 62, and a target damping force correction unit 63. It consists of. The target damping force setting units 61fl to 61rr are set in consideration of the operating characteristics of the suspension 7 based on the vertical accelerations Gzfl to Gzrr, which are detected values of the vertical G sensors 13fl to 13rr close to the wheels 3fl to 3rr. Target damping forces Dtfl to Dtrr are set using the wheel vibration model. In addition, the damping force correction value setting unit 62 calculates damping force correction values Dcfl to Dcrr, which will be described in detail later, on the basis of the vertical accelerations Gzfl to Gzrr in order to interpolate the target damping forces Dtfl to Dtrr. Set each. The target damping force correction unit 63 corrects the target damping forces Dtfl to Dtrr based on the damping force correction values Dcfl to Dcrr, respectively.

  Next, processing performed by the damping force control device 50 will be described with reference to FIG. When the vehicle V starts traveling, the damping force control device 50 executes damping force control whose procedure is shown in the flowchart of FIG. 5 at a predetermined processing interval (for example, 10 ms). When the damping force control is started, the damping force control device 50 detects the vehicle body speed input from the vehicle speed sensor 9, the acceleration of the vehicle body 1 obtained from the lateral G sensor 10, the front and rear G sensor 11, and the vertical G sensor 13, and the steering angle. The motion state of the automobile V is determined based on the steering speed and the like input from a sensor (not shown). Next, the damping force control device 50 calculates the skyhook control target value Dsh of each damper 6 based on the motion state of the automobile V by a skyhook calculation process described later in detail with reference to an embodiment (step 2). Then, the roll control target value Dr of each damper 6 is calculated (step 3), and the pitch control target value Dp of each damper 6 is calculated (step 4).

  Next, the damping force control device 50 determines whether or not the stroke speed Ss of each damper 6 is a positive value (step 5). If this determination is Yes (that is, the damper 6 is on the extension side). The largest control value among the three control target values Dsh, Dr, Dp is set as the target damping force Dtgt (step 6). The damping force control device 50 has the largest value among the three control target values Dsh, Dr, and Dp when the determination in step S5 is No (that is, when the damper 6 is operating on the contraction side). The smaller one is set as the target damping force (step 7).

  When the target damping force Dtgt is set, the damping force control device 50 searches / sets the target current from the target current map of FIG. 6 (step 8). Next, the damping force control device 50 outputs a drive current to the MLV coil 42 of each damper 6 based on the set target current (step 10).

  Next, the skyhook calculation process will be described in detail. The skyhook calculation control unit 55 performs the same skyhook calculation process for the damper 6 corresponding to each wheel 3, but only the damper 6fl corresponding to the left front wheel 3fl will be described below.

  FIG. 7 is a flowchart illustrating the procedure of the skyhook calculation control process according to the first embodiment. First, the skyhook calculation control unit 55 calculates the vertical speeds Vzfl, Vzfr, Vzrl, Vzrr from the integrated values of the vertical accelerations Gzfl, Gzfr, Gzrl, Gzrr of the damper base 1a corresponding to each wheel 3 (step S11). Next, the skyhook calculation control unit 55 sets the target damping force Dtfl in the target damping force setting unit 61fl by referring to a predetermined map based on the vertical speed Vzfl of the left front damper base 1afl (step S12). ). Next, the skyhook calculation control unit 55 calculates the average value Vza of the vertical speeds Vzfr, Vzrl, Vzrr of the right front, left rear, and right rear damper base 1a in the damping force correction value setting unit 62fl (step S13). The damping force correction value Dcfl is set by referring to a predetermined map based on the average value Vza (step S14).

Next, the skyhook calculation control unit 55 determines whether or not the input to the left front damper base 1afl and the other inputs to the damper bases 1afr, 1arl, and 1arr are in phase in the target damping force correction unit 63fl, That is, whether or not the vertical speed Vzfl and the average value Vza have the same sign is determined by the following expression 1 (step S15).
Vzfl · Vza> 0 (1)
When the input to the left front damper base 1afl and the other input to the damper base 1a are in phase (step S15: Yes), the target damping force correction unit 63fl calculates the skyhook from the target damping force Dtfl by the following equation 2. A control target value Dshfl is calculated (step S16).
Dshfl = K1 · Dtfl (2)
However, K1: It is a coefficient.
On the other hand, when the input to the left front damper base 1afl and the other inputs to the damper base 1a are in opposite phases (step S15: No), the target damping force correction unit 63fl corrects the target damping force Dtfl and the damping force correction. The skyhook control target value Dshfl is calculated from the value Dcfl by the following expression 3 (step S17).
Dshfl = K1 (Dtfl−K2 · Dcfl) (3)
Where K2 is a coefficient.
Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S18), and the process ends.

  In the present embodiment, by performing such processing, the damping force correction value Dcfl of the left front damper 6fl has three dampers 6rl, 6fr in the vehicle front-rear direction, the left-right direction, and the diagonal direction with respect to the left front damper 6fl. , 6rr is set based on the average value Vza of the vertical speeds Vzrl, Vzfr, Vzrr of the damper bases 1arl, 1afr, 1arr. When the three damper bases 1a have inputs of opposite phases, the vehicle V is regarded as having a large change in attitude, and the target damping force Dtcfl (conventional) is obtained by subtracting the damping force correction value Dcfl from the target damping force Dtcfl. The skyhook control target value Dshfl is set so that the absolute value thereof is larger than the target damping force). Therefore, the posture change of the vehicle body 1 is efficiently suppressed.

  If the three damper bases 1a have in-phase inputs, the in-phase inputs are considered to suppress the change in posture of the vehicle V, and the damper 6fl is not affected by the vertical speed Vz of the three damper bases 1a. Skyhook control target value Dshfl is set. Therefore, the skyhook control target value Dshfl is set based on the target damping force Dtc without causing the damper 6fl to generate more damping force than necessary, and the attitude change of the automobile V is appropriately suppressed.

  Next, a procedure for skyhook calculation control processing according to the second embodiment will be described with reference to FIG. In the embodiment described below, the same processing as in the first embodiment will be described briefly. As shown in the flowchart of FIG. 8, the skyhook calculation control unit 55 first calculates the vertical speeds Vzfl, Vzfr, Vzrl, Vzrr (step S21), and the target damping force setting unit 61fl based on the vertical speed Vzfl. The target damping force Dtfl is set by referring to a predetermined map (step S22). Next, in the damping force correction value setting unit 62fl, the skyhook calculation control unit 55 determines whether the left front damper base 1afl is up or down from among the vertical speeds Vzfr, Vzrl, Vzrr of the right front, left rear, and right rear damper base 1a. A value having the maximum difference from the speed Vzfl is selected as the maximum value Vzm (step S23), and a damping force correction value Dcfl is set by referring to a predetermined map based on the maximum value Vzm (step S24).

Next, the skyhook calculation control unit 55 determines whether or not the input to the left front damper base 1afl and the input to the damper base 1a selected as the maximum value Vzm are in phase in the target damping force correction unit 63fl. That is, whether or not the vertical speed Vzfl and the maximum value Vzm have the same sign is determined by the following expression 4 (step S25).
Vzfl · Vzm> 0 (4)
When the input to the left front damper base 1afl and the input to the damper base 1a related to the maximum value Vzm are in phase (step S25: Yes), the target damping force correction unit 63fl uses the above equation 2 to calculate the skyhook control target. A value Dshfl is calculated (step S26). On the other hand, when the input to the left front damper base 1afl and the input to the damper base 1a related to the maximum value Vzm are in reverse phase (step S25: No), the target damping force correction unit 63fl calculates the sky by the above equation 3. A hook control target value Dshfl is calculated (step S27). Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S28), and the process ends.

  In the present embodiment, by performing such a process, the damping force correction value Dcfl of the left front damper 6fl causes the vertical speeds of the damper bases 1arl, 1afr, 1arr adjacent to the other three dampers 6rl, 6fr, 6rr. A difference from the vertical velocity Vzfl is set based on the maximum value Vzm selected as the maximum from Vzrl, Vzfr, Vzrr. If the three damper bases 1a have inputs of opposite phases, the vehicle V is regarded as having a large attitude change, and the target value is obtained by subtracting the damping force correction value Dcfl based on the damper base 1a having the highest vertical speed Vz. Skyhook control target value Dshfl is set such that the absolute value thereof is larger than damping force Dtcfl (conventional target damping force). Therefore, the posture change of the vehicle body 1 is efficiently suppressed.

  Similarly to the first embodiment, when the three damper bases 1a have in-phase inputs, the skyhook control target value Dshfl of the damper 6fl is more than necessary without being affected by the vertical speed Vz of the three damper bases 1a. Since the setting is made without generating the damping force, the posture change of the automobile V is appropriately suppressed.

Next, a procedure for skyhook calculation control processing according to the third embodiment will be described with reference to FIG. As shown in the flowchart of FIG. 9, the skyhook calculation control unit 55 first calculates the vertical speeds Vzfl, Vzfr, Vzrl, Vzrr (step S31), and the target damping force setting unit 61fl based on the vertical speed Vzfl. The target damping force Dtfl is set by referring to a predetermined map (step S32). Next, in the damping force correction value setting unit 62fl, the skyhook calculation control unit 55 calculates the average value Vzfa from the vertical speeds Vzfl and Vzfr of the left and right damper bases 1afl and 1afr at the front of the vehicle body by the following expression 5. An average value Vzra is calculated from the vertical speeds Vzrl and Vzrr of the left and right damper bases 1arl and 1arr at the rear of the vehicle body according to the following equation 6 (step 33).
Vzfa = (Vzfl + Vzfr) / 2 (5)
Vzra = (Vzrl + Vzrr) / 2 (6)
Then, the damping force correction value setting unit 62fl sets the damping force correction value Dcfl by referring to a predetermined map based on the average value Vzra of the vertical speed of the rear part of the vehicle body (step S34).

Next, in the target damping force correction unit 63fl, the skyhook calculation control unit 55 performs input to the front part of the vehicle body (damper base 1afl, damper base 1afr) and input to the rear part of the vehicle body (damper base 1arl, damper base 1arr). Is in phase, that is, whether or not the average value Vzfa of the front part of the vehicle body and the average value Vzra of the rear part of the vehicle body have the same sign is determined by the following expression 7 (step S35).
Vzfa · Vzra> 0 (7)
When the input to the front part of the vehicle body and the input to the rear part of the vehicle body are in phase (step S35: Yes), the target damping force correction unit 63fl calculates the skyhook control target value Dshfl by the above-described equation 2 (step S36). ). On the other hand, when the input to the front part of the vehicle body and the input to the rear part of the vehicle body are in opposite phases (step S35: No), the target damping force correction unit 63fl calculates the skyhook control target value Dshfl by the above-described equation 3. (Step S37). Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S38), and the process ends.

  In this embodiment, by performing such processing, the damping force correction value Dcfl of the left front damper 6fl is set based on the input of the rear part of the vehicle body (average value Vzra of the vertical speed of the rear part of the vehicle body). When the vehicle body rear portion has an input in reverse phase to the vehicle body front portion, it is assumed that the pitch change of the vehicle V is large, and the target value is obtained by subtracting the damping force correction value Dcfl based on the damper bases 1arl and 1arr at the vehicle body rear portion. Skyhook control target value Dshfl is set such that the absolute value thereof is larger than damping force Dtcfl (conventional target damping force). Therefore, the pitch change of the vehicle body 1 is efficiently suppressed.

  When there is an input in phase with the front part of the vehicle body at the rear part of the vehicle body, the skyhook control target value Dshfl of the damper 6fl is not affected by the average value Vzra of the vertical speeds of the damper bases 1arl and 1arr at the rear part of the vehicle body. Since the setting is made without generating more damping force than necessary, the pitch change of the automobile V is appropriately suppressed.

  Furthermore, with reference to FIG. 10, the procedure of the skyhook calculation control process which concerns on Example 4 is demonstrated. As shown in the flowchart of FIG. 10, the skyhook calculation control unit 55 first calculates the vertical speeds Vzfl and Vzrl from the vertical accelerations Gzfl and Gzrl of the left damper bases 1afl and 1arl (step S41), and sets the target damping force. In the part 61fl, the target damping force Dtfl is set by referring to a predetermined map based on the vertical speed Vzfl (step S42). Then, the skyhook calculation control unit 55 sets the damping force correction value Dcfl by referring to a predetermined map based on the vertical speed Vzrl in the damping force correction value setting unit 62fl (step S43).

Next, the skyhook calculation control unit 55 determines whether or not the input to the left front damper base 1afl and the input to the left rear damper base 1arl are in phase in the target damping force correction unit 63fl, that is, the vertical speed Vzfl. And the vertical speed Vzrl are determined by the following equation 8 (step S44).
Vzfl · Vzrl> 0 (8)
When the input to the left front damper base 1afl and the input to the left rear damper base 1arl are in phase (step S44: Yes), the target damping force correction unit 63fl uses the above equation 2 to calculate the skyhook control target value Dshfl. Is calculated (step S45). On the other hand, when the input to the left front damper base 1afl and the input to the left rear damper base 1arl are in opposite phases (step S44: No), the target damping force correction unit 63fl controls the skyhook control according to the above equation 3. A target value Dshfl is calculated (step S46). Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S47), and the process ends.

  In this embodiment, by performing such processing, the damping force correction value Dcfl of the left front damper 6fl is set based on the input (vertical speed Vzrl) to the left rear damper base 1arl. When the left rear damper base 1arl has an input opposite to the left front damper base 1afl, it is assumed that the left side of the vehicle body 1 has a large pitch change, and the damping force correction value Dcfl based on the left rear damper base 1arl is obtained. By subtracting, the skyhook control target value Dshfl is set so that its absolute value becomes larger than the target damping force Dtcfl (conventional target damping force). Therefore, the pitch change of the vehicle body 1 is efficiently suppressed.

  When the left rear damper base 1arl has an input in phase with the left front damper base 1afl, the skyhook control target value Dshfl of the damper 6fl is not affected by the vertical speed Vzrl of the left rear damper base 1arl. That is, since the setting is made without generating an excessive damping force, the pitch change of the automobile V is appropriately suppressed.

  Here, when a vibration that is 180 degrees different from the front and rear wheels 3 (reverse phase) is applied to the vehicle V when the vehicle V is 1.2 Hz, the amplitude is 7 mm, the conventional technique (skyhook control target value) is used. FIG. 11 shows a graph comparing Dshfl = target damping force Dt) and Examples 3 and 4 (skyhook control target value Dshfl = target damping force Dt−damping force correction value Dc). In the third embodiment, the damping force correction value Dc is set for each wheel 3 based on the average value Vzfa of the vertical speed of the front part of the vehicle body or the average value Vzra of the vertical speed of the rear part of the vehicle body. 4 sets a damping force correction value Dc for each wheel 3 based on the vertical speed Vz of the damper base 1a corresponding to the front or rear wheel 3 in the same vehicle width direction. In the figure, the time axis is shifted in order to avoid difficulty in discriminating the graph. As can be seen from FIG. 11, in both Example 3 and Example 4, the pitch rate of the vehicle body 1 when a reverse-phase input is made is reduced as compared with the prior art.

  Furthermore, with reference to FIG. 12, the procedure of the skyhook calculation control process which concerns on Example 5 is demonstrated. As shown in the flowchart of FIG. 12, the skyhook calculation control unit 55 first calculates the vertical speeds Vzfl and Vzfr from the vertical accelerations Gzfl and Gzfr of the damper bases 1afl and 1afr at the front of the vehicle body (step S51). In the force setting unit 61fl, the target damping force Dtfl is set by referring to a predetermined map based on the vertical speed Vzfl (step S52). Then, the skyhook calculation control unit 55 sets the damping force correction value Dcfl in the damping force correction value setting unit 62fl by referring to a predetermined map based on the vertical speed Vzfr (step S53).

Next, in the target damping force correction unit 63fl, the skyhook calculation control unit 55 determines whether or not the input to the left front damper base 1afl and the input to the right front damper base 1afr are in phase, that is, the vertical speed Vzfl. Whether or not the vertical speed Vzfr has the same sign is determined by the following expression 9 (step S54).
Vzfl · Vzfr> 0 (9)
When the input to the left front damper base 1afl and the input to the right front damper base 1afr are in phase (step S54: Yes), the target damping force correction unit 63fl calculates the skyhook control target value Dshfl by the above equation 2. Calculate (step S55). On the other hand, when the input to the left front damper base 1afl and the input to the right front damper base 1afr are in opposite phases (step S54: No), the target damping force correction unit 63fl uses the above equation 3 to calculate the skyhook control target. A value Dshfl is calculated (step S56). Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S57), and the process ends.

  In this embodiment, by performing such processing, the damping force correction value Dcfl of the left front damper 6fl is set based on the input (vertical speed Vzfr) to the right front damper base 1afr. When the right front damper base 1afr has an input opposite in phase to the left front damper base 1afl, it is assumed that the roll change of the front portion of the vehicle body 1 is large, and the damping force correction value Dcfl based on the right front damper base 1afr is subtracted. Thus, the skyhook control target value Dshfl is set so that the absolute value thereof is larger than the target damping force Dtcfl (conventional target damping force). Therefore, the roll change of the vehicle body 1 is efficiently suppressed.

  When the right front damper base 1arl has an input in phase with the left front damper base 1afl, the skyhook control target value Dshfl of the damper 6fl is not affected by the vertical speed Vzrl of the right front damper base 1arl, that is, necessary. Since it is set without generating the above damping force, the roll change of the automobile V is appropriately suppressed.

  Here, when a vibration different from the right and left wheels 3 by 180 degrees with respect to the left and right wheels 3 (in the opposite phase) is applied to the vehicle V, the conventional technology (the skyhook control target value) for the roll rate of the vehicle body 1 is applied. FIG. 13 shows a graph comparing Dshfl = target damping force Dt) and Example 5 (skyhook control target value Dshfl = target damping force Dt−damping force correction value Dc). In the fifth embodiment, for each wheel 3, the damping force correction value Dc is set based on the vertical speed Vz of the damper base 1a corresponding to the left or right wheel 3 paired with the wheel 3. As can be seen from FIG. 13, in Example 5, the roll rate of the vehicle body 1 when there is an input in reverse phase is reduced as compared with the prior art.

  Furthermore, with reference to FIG. 14, the procedure of the skyhook calculation control process which concerns on Example 6 is demonstrated. As shown in the flowchart of FIG. 14, the skyhook calculation control unit 55 first calculates the vertical speeds Vzfl and Vzrr from the vertical accelerations Gzfl and Gzrr of the right rear damper base 1arr that is diagonally opposite the left front damper base 1afl. In step S61, the target damping force setting unit 61fl sets the target damping force Dtfl by referring to a predetermined map based on the vertical speed Vzfl (step S62). Then, the skyhook calculation control unit 55 sets the damping force correction value Dcfl in the damping force correction value setting unit 62fl by referring to a predetermined map based on the vertical speed Vzrr (step S63).

Next, the skyhook calculation control unit 55 determines whether or not the input to the left front damper base 1afl and the input to the right rear damper base 1arr are in phase in the target damping force correction unit 63fl, that is, the vertical speed Whether or not Vzfl and the vertical speed Vzrr have the same sign is determined by the following expression 9 (step S64).
Vzfl · Vzrr> 0 (9)
When the input to the left front damper base 1afl and the input to the right rear damper base 1arr are in phase (step S64: Yes), the target damping force correction unit 63fl uses the above equation 2 to calculate the skyhook control target value Dshfl. Is calculated (step S65). On the other hand, when the input to the left front damper base 1afl and the input to the right rear damper base 1arr are in reverse phase (step S64: No), the target damping force correction unit 63fl controls the skyhook control according to the above equation 3. A target value Dshfl is calculated (step S66). Then, the skyhook control target value Dshfl is output to the damping force setting unit 52 (step S67), and the process ends.

  In this embodiment, by performing such processing, the damping force correction value Dcfl of the left front damper 6fl is set based on the input (vertical speed Vzrr) to the right rear damper base 1arr. When the right rear damper base 1arr has an input opposite in phase to the left front damper base 1afl, it is considered that the roll change and pitch change of the vehicle body 1 are large, and the damping force correction value Dcfl based on the right rear damper base 1arr. Is subtracted, the skyhook control target value Dshfl is set so that its absolute value becomes larger than the target damping force Dtcfl (conventional target damping force). Therefore, both the roll change and the pitch change of the vehicle body 1 are efficiently suppressed.

  When the right rear damper base 1arl has an input in phase with the left front damper base 1afl, the skyhook control target value Dshfl of the damper 6fl is not affected by the vertical speed Vzrl of the right rear damper base 1arl. That is, since the setting is made without generating an excessive damping force, the pitch change and roll change of the automobile V are appropriately suppressed.

  Here, when a vibration different from the right and left wheels 3 by 180 degrees with respect to the left and right wheels 3 (in the opposite phase) is applied to the vehicle V, the conventional technology (the skyhook control target value) for the roll rate of the vehicle body 1 is applied. A graph comparing Dshfl = target damping force Dt) and Example 6 (skyhook control target value Dshfl = target damping force Dt−damping force correction value Dc) is shown in FIG. A graph comparing Example 6 is shown in FIG. In the sixth embodiment, the damping force correction value Dc is set for each wheel 3 based on the vertical speed Vz of the damper base 1a corresponding to the wheel 3 that is diagonally opposite the wheel 3. As can be seen from FIG. 15, in the sixth embodiment, the roll rate of the vehicle body 1 when there is an input in reverse phase is reduced as compared with the prior art. Further, as can be seen from FIG. 16, in the sixth embodiment, the pitch rate of the vehicle body 1 when there is an input in reverse phase is also reduced compared to the prior art.

  Although description of specific embodiment is finished above, the aspect of the present invention is not limited to the above embodiment. For example, in the above embodiment, the vertical G sensor is used as the state quantity detection means and the vertical speed is adopted as the movement state quantity. For example, a correction value is set based on the vertical acceleration, or the lateral G and the front and rear of each vehicle body part are set. A correction value may be set based on G. Moreover, in the said embodiment, what sets a correction value based only on the vehicle body part of the front-back direction is shown in Example 4, and what sets a correction ground only based on the vehicle body part of the vehicle width direction is shown in Example 5, respectively. Although shown, it is good also as an Example which performs these together. In addition, the specific configuration of the control device, the specific control procedure, the setting method, the calculation method, and the like can be changed as appropriate without departing from the spirit of the present invention.

1 Body 1a Damper base (body part)
3 Wheel 6 Damper 7 Suspension 13 Vertical G sensor (Motion state quantity detection means)
DESCRIPTION OF SYMBOLS 50 Damping force control apparatus 55 Skyhook calculation control part 61 Target damping force setting part 62 Damping force correction value setting part 63 Target damping force correction part V Car Dsh Skyhook control target value Dt Target damping force Dc Damping force correction value Vz Vertical speed Vza Average vertical speed Vzm Maximum vertical speed

Claims (5)

A damping force variable damper control device that is installed in a four-wheel vehicle and variably controls the damping force of a damper disposed between a vehicle body and each wheel,
A movement state quantity detecting means provided at each vehicle body part adjacent to each damper, and detecting a movement state quantity of the vehicle body part;
Target damping force setting means for setting a target damping force of a damper adjacent to each motion state quantity detection means based on the detection result of each motion state quantity detection means;
A correction value for setting a damping force correction value for one damper based on a movement state quantity of a vehicle body part adjacent to another damper having the largest difference from a movement state quantity of a vehicle body part adjacent to the damper. Setting means;
A damping force variable damper control device comprising: a target damping force correcting unit that corrects the target damping force based on the damping force correction value. The amount of motion state relates to vertical motion,
The target damping force correction means increases the absolute value of the target damping force when the movement direction of the vehicle body part adjacent to the one damper is different from the movement direction of the vehicle body part adjacent to the other damper. The control device for a variable damping force damper according to claim 1, wherein correction is performed. The amount of motion state relates to vertical motion,
The target damping force correction means performs the correction only when the movement direction of the vehicle body part adjacent to the one damper is different from the movement direction of the vehicle body part adjacent to the other damper. A control device for a damping force variable damper according to claim 1 or 2. A vehicle body part close to one damper moves up and down at a first vertical speed, and a vehicle body part close to another damper moves up and down at a second vertical speed.
The target damping force setting means sets a target damping force of the one damper based on the first vertical speed,
4. The damping force variable damper according to claim 1, wherein the correction value setting unit sets a correction value of the one damper based on the second vertical speed. 5. Control device. A method of variably controlling the damping force of a damping force variable damper disposed between a vehicle body and each wheel in a four-wheel vehicle,
Detecting a motion state quantity of a vehicle body part adjacent to each damper;
Setting a target damping force to be generated in a damper adjacent to each vehicle body part based on the detected motion state quantity of each vehicle body part;
Setting a damping force correction value for one damper based on a motion state quantity of a vehicle body part adjacent to another damper having a largest difference from a motion state quantity of a vehicle body part adjacent to the damper; ,
And a step of correcting the target damping force based on the damping force correction value.

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