JP2005041289A - Suspension control system for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suspension control system for a vehicle having a plurality of suspension devices capable of enhancing the handling stability of the vehicle and/or the riding comfort of each occupant by controlling the damping forces of the suspension devices individually so as to suit the in-cabin situation of the occupants in the vehicle. <P>SOLUTION: The suspension control system of the vehicle has occupant sensors 40a-40d to sense the loads applied to the seat bottoms of the driver seat, the rear left seat, the assistant seat, and the rear left seat. A microcomputer 50 calculates the damping coefficients of the suspension devices so that their degrees of damping become the same on the basis of the load of the vehicle body B and a damping coefficient ratio common to the suspension devices S1-S4 and controls the suspension devices so that their elongation/contraction speeds become the same on the basis of the obtained damping coefficients. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle suspension control system.
[0002]
[Prior art]
Conventionally, in this type of vehicle suspension control system, there is an automobile suspension control system disclosed in Patent Document 1 below. According to this suspension control system, each suspension device interposed between each lower arm and the vehicle body in the vicinity of each wheel of the vehicle is driven by the damping force from the road surface of the vehicle via each wheel. It is controlled to absorb the acting shock.
[0003]
[Patent Document 1]
JP-A-5-345509
[0004]
[Problems to be solved by the invention]
By the way, in the suspension control system, the damping force of each suspension device is calculated in common to each suspension device based on the driving situation of the vehicle and road environment information from the in-vehicle navigation device.
[0005]
However, since the suspension control system does not take into account the passenger's boarding situation in the vehicle, for example, when the passenger is seated only in the driver's seat and when the passenger is seated in both the driver's seat and the rear seat. Then, the load applied to each suspension device is different.
[0006]
Therefore, the damping force of each suspension device cannot be controlled so as to be suitable for the riding conditions of each occupant in the vehicle, and as a result, the driving stability and riding comfort of the vehicle are deteriorated.
[0007]
Therefore, in order to deal with the above, the present invention separately controls the damping force of each suspension device so as to be suitable for the occupant's riding situation in the vehicle. An object of the present invention is to provide a vehicle suspension control system that improves the riding comfort of the vehicle.
[0008]
[Means for Solving the Problems]
In solving the above-described problem, a vehicle suspension control system according to the present invention is as described in claim 1.
It is interposed between the unsprung members (R1, R2) and the sprung member (B) of the vehicle so as to absorb the impact acting between the unsprung member and the sprung member. A suspension device (S1 to S4) that is extended and contracted;
A plurality of occupant sensors (40a to 40d) for detecting a load acting on each seating portion of a plurality of seats of the vehicle;
Based on the detection load of the plurality of occupant sensors, the load of the sprung member, and the damping factor ratio common to each suspension device, the damping factor of each suspension device is set so that the degree of damping of each suspension device is the same. Attenuation coefficient calculation means (150) for calculating,
Each suspension device is controlled based on each damping coefficient.
[0009]
According to this, based on each detected load, the load of the sprung member, and the damping coefficient ratio common to each suspension device, the damping coefficient of each suspension device is calculated so that the degree of damping of each suspension device is the same. As a result, the suspension devices are controlled independently from each other based on the corresponding damping coefficients so that the expansion and contraction speeds thereof are the same.
[0010]
Therefore, each suspension device is individually controlled by an optimum damping coefficient, that is, damping force in accordance with the riding situation of each occupant, and as a result, the steering stability of the vehicle and the riding comfort for each occupant can be improved.
[0011]
According to a second aspect of the present invention, there is provided a vehicle suspension control system according to the present invention.
Between the unsprung member (R1, R2) and the sprung member (B) of the vehicle on which the navigation device (N) is mounted, the unsprung member and the sprung member A suspension device (S1 to S4) that expands and contracts so as to absorb an impact acting between them;
A plurality of occupant sensors (40a to 40d) for detecting a load acting on each seating portion of a plurality of seats of the vehicle;
Corner determining means (136) for determining whether or not the vehicle is passing the corner (T) of the traveling path based on the traveling path information of the vehicle from the navigation device;
When it is determined that the corner determining means is not passing through the corner, a normal driving damping coefficient ratio common to each suspension device is set, and when the corner determining means determines that the corner is passing, the vehicle from the navigation device is Damping coefficient ratio setting means (133, 138, 135) for setting a corner running damping coefficient ratio common to each suspension device based on information representing a speed difference between the current speed and the recommended approach speed for the corner;
Based on the normal driving damping coefficient ratio or corner driving damping coefficient ratio and the detected loads of the plurality of occupant sensors and the loads of the sprung members, the damping coefficient of each suspension device is made the same as the degree of damping of each suspension device. And an attenuation coefficient calculating means (150) for calculating each,
Each suspension device is controlled based on each damping coefficient.
[0012]
In this way, if the damping coefficient ratio that is set using the output information of the navigation device during the corner passage or corner non-passing of the vehicle is used to calculate the damping coefficient of each suspension device, Each damping coefficient suitable for cornering is calculated independently so that each suspension device has the same degree of damping.
[0013]
Accordingly, each suspension device is individually controlled with an optimum damping coefficient, that is, a damping force according to the riding conditions of each occupant during normal traveling or corner traveling of the vehicle, and as a result, during normal traveling or corner traveling of the vehicle. At any time, the handling stability of the vehicle and the ride comfort for each occupant can be improved.
[0014]
According to a third aspect of the present invention, in the suspension control system for a vehicle according to the first or second aspect, the damping coefficient calculation means detects each of the suspension devices so that the degree of attenuation is the same. The load is weighted to be each weighted load, and each weighted load is used for calculation of each attenuation coefficient instead of each detected load.
[0015]
According to this, each attenuation coefficient is calculated as a value that more closely matches the passenger's boarding situation with respect to the vehicle, and as a result, the operational effect of the invention according to claim 1 or 2 can be further improved.
[0016]
According to a fourth aspect of the present invention, there is provided a vehicle suspension control system according to the present invention.
It is interposed between the unsprung members (R1, R2) and the sprung member (B) of the vehicle so as to absorb the impact acting between the unsprung member and the sprung member. A suspension device (S1 to S4) that is extended and contracted;
Suspension load calculating means for calculating a load applied to each suspension device based on relative displacement between the unsprung member and the sprung member;
Based on each calculated load calculated by the suspension load calculating means, the load of the sprung member, and the damping coefficient ratio common to each suspension apparatus, the damping coefficient of each suspension apparatus is made the same as the degree of attenuation of each suspension apparatus. And an attenuation coefficient calculating means for calculating each of
Each suspension device is controlled based on each damping coefficient.
[0017]
According to this, even if each suspension load applied to each suspension device is calculated based on the relative displacement between the unsprung member and the unsprung member, the same effect as that of the invention according to claim 1 can be obtained. be able to.
[0018]
In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an example in which a suspension control system according to the present invention is applied to a sedan type automobile. This suspension control system includes suspension devices S1 to S4 and an electronic control device E.
[0020]
As shown in FIG. 2, the suspension device S1 includes a lower arm R1 (unsprung member) provided in the vicinity of the right front wheel of the vehicle and a corresponding part of the vehicle body B (sprung member) with respect to the lower arm R1 (hereinafter, right side). It is also interposed between the front wheel corresponding part).
[0021]
As shown in FIG. 3, the suspension device S1 includes a damper 10 and a coil spring 20, and the damper 10 is supported on the lower arm R1 at the lower end thereof. The coil spring 20 is coaxially fitted to the damper 10 from the outside between a flange portion 10a provided at an axially intermediate portion of the outer peripheral surface of the damper 10 and the right front wheel corresponding portion of the vehicle body B. . As a result, the coil spring 20 biases the right front wheel corresponding part of the vehicle body B upward.
[0022]
Here, the configuration and function of the damper 10 will be described using the equivalent circuit shown in FIG. The damper 10 includes a piston 11 and a hydraulic cylinder 12, and the piston 11 is fitted in the cylinder 12 so as to be slidable in the axial direction. Divide into 12b.
[0023]
Further, the damper 10 includes an electromagnetic throttle valve 13, and the electromagnetic throttle valve 13 communicates both hydraulic chambers 12a and 12b based on the throttle opening. Further, the damper 10 includes a piston rod 14, which extends from the piston 11 through the hydraulic chamber 12a and is connected to the right front wheel corresponding portion of the vehicle body B at the upper end thereof. Yes.
[0024]
In the damper 10 configured as described above, when the piston 11 slides upward, the hydraulic oil in the hydraulic chamber 12a flows through the electromagnetic throttle valve 13 and into the hydraulic chamber 12b. When the piston 11 slides downward, the hydraulic oil in the hydraulic chamber 12b flows through the electromagnetic throttle valve 13 and into the hydraulic chamber 12a. In the present embodiment, the electromagnetic throttle valve 13 adjusts the flow amount of the hydraulic oil between the hydraulic chambers 12a and 12b according to the throttle opening degree. It decreases (or increases) in response to an increase (or decrease) in the flow resistance of the hydraulic oil in the throttle valve 13 (that is, corresponding to the damping force of the damper 10 and the suspension device S1).
[0025]
The suspension device S2 is interposed between a lower arm R2 provided in the vicinity of the right rear wheel of the vehicle and a corresponding portion of the vehicle body B with respect to the lower arm R2 (hereinafter also referred to as a right rear wheel corresponding portion). ing. The suspension device S3 (see FIG. 1) is provided between a lower arm (not shown) provided in the vicinity of the left front wheel of the vehicle and a corresponding portion of the vehicle body B with respect to the lower arm (hereinafter also referred to as a left front wheel corresponding portion). It is intervened. The suspension device S4 (see FIG. 1) includes a lower arm (not shown) provided in the vicinity of the left rear wheel of the vehicle and a corresponding portion of the vehicle body B with respect to the lower arm (hereinafter also referred to as a left rear wheel corresponding portion). It is intervened between.
[0026]
Each of the suspension devices S2 to S4 includes a damper 10 and a coil spring 20 similarly to the suspension device S1, and each of the suspension devices S2 to S4 is separated from the suspension device S1 by the damper 10 and the coil spring 20. It performs the same function.
[0027]
Next, the configuration of the electronic control device E will be described in relation to the navigation device N based on FIG. The navigation device N includes a gyro sensor 30a, a GPS sensor 30b, and a vehicle speed sensor 30c, and the gyro sensor 30a detects the traveling direction of the automobile. The GPS sensor 30b detects the current position of the vehicle based on radio waves from a plurality of geostationary satellites. The vehicle speed sensor 30c detects the traveling speed of the vehicle.
[0028]
The navigation device N includes an input device 30d, a storage device 30e, a computer 30f, and an output device 30g, and the input device 30d inputs necessary information to the computer 30f by its operation. A series of map data is stored in the storage device 30e as a database so that it can be read out by the computer 30f.
[0029]
The computer 30f executes the navigation control program according to the flowcharts shown in FIGS. During the execution of the navigation control program, the computer 30f determines the route of the vehicle based on the operation output of the input device 30d, the stored data of the storage device 30e, and the detection outputs of the gyro sensor 30a, GPS sensor 30b, and vehicle speed sensor 30c. Processing necessary for guidance and processing necessary for analysis of the driving environment of the car are performed. The output device 30g displays data necessary for the vehicle as information under the control of the computer 30f.
[0030]
As shown in FIG. 1, the electronic control unit E includes occupant sensors 40a to 40d, a microcomputer 50, and drive circuits 60a to 60d.
[0031]
The occupant sensor 40a is built in the seating portion 71 of the driver's seat 70a (see FIG. 5) of the automobile, and the occupant sensor 40a detects a load applied on the seating portion 71. The occupant sensor 40b is built in the right seat 72 of the rear seat 70b (see FIG. 5) of the vehicle, and the occupant sensor 40b detects a load applied on the seat 72.
[0032]
The occupant sensor 40c is built in the seating portion 73 of the passenger seat 70c (see FIG. 5) of the automobile, and the occupant sensor 40c detects a load applied on the seating portion 73. The occupant sensor 40d is built in the left seating portion 74 of the rear seat 70d (see FIG. 5) of the automobile, and the occupant sensor 40d detects a load applied on the seating portion 74. In addition, the load concerning each seating part 71-74 is also hereafter called a seat load, and as this seat load, it is mounted in the weight of the passenger | crew who sits on each said seating part 71-74, or each seating part 71-74. Luggage.
[0033]
The microcomputer 50 executes the suspension control program according to the flowcharts shown in FIGS. During execution of the suspension control program, the microcomputer 50 determines the degree of attenuation of each suspension device S1 to S4 based on the output of the computer 30f of the navigation device N and the detection outputs of the occupant sensors 40a to 40d and the vehicle speed sensor 30c. Performs processing necessary for adjustment.
[0034]
The drive circuits 60a to 60d are controlled by the microcomputer 50 to drive the electromagnetic throttle valves 13 of the suspension devices S1 to S4.
[0035]
In the present embodiment configured as described above, when the computer 30f of the navigation device N starts executing the navigation control program according to the flowchart of FIG. 6, it is necessary for route guidance of the navigation device N in the navigation basic processing routine 100. The basic processing is as follows (see FIG. 7).
[0036]
First, if there is a request for displaying a desired map by operating the input device 30d, YES is determined in step 101 of FIG. In step 102, the map data representing the desired map is read out. Accordingly, the map data is read from the storage device 30e. Thereafter, in step 103, the desired map display process is performed. For this reason, the output device 30g displays the desired map based on the map data.
[0037]
Next, in step 104, route search processing is performed. In this route search process, a route search is performed on the display map based on detection outputs of the gyro sensor 30a and the GPS sensor 30b and an input destination by the input device 30d. In step 105, route guidance processing for the vehicle is performed based on the route search result. Accordingly, the car travels along the search guidance route.
[0038]
When the processing of the navigation basic processing routine 100 is completed as described above, the processing of the traveling environment recognition processing routine 110 (see FIG. 6 and FIG. 8) is performed as follows. First, as shown in FIG. 11, a position where the traveling road starts to bend from a straight road to a corner T (hereinafter referred to as a “curve start point K”), a radius of curvature of the corner T, and the corner T It is assumed that a plurality of nodes N serving as reference positions for calculating a recommended approach speed by an automobile are set along the road on the map data.
[0039]
Therefore, in step 111 of FIG. 8, the curve starting point K is determined as follows.
[0040]
First, as shown in FIG. 11, at each node N existing in the traveling direction of the automobile, an angle formed by the straight line Ya and the straight line Yb is calculated as the turning angle θ. Here, the straight line Ya is a straight line passing through nodes existing before and after a position separated by a predetermined distance La from the target node to the rear thereof. Further, the straight line Yb is a straight line passing through nodes existing before and after a position separated from the target node by a predetermined distance Lb forward.
[0041]
As described above, when the turning angle θ is calculated for each node N, the first node that specifies the turning angle θ larger than a predetermined value is determined as the turning point K. In step 112, the radius of curvature of the corner T as the curved path is calculated as a radius of a circle passing through a total of three nodes including two nodes located before and after the target node N in the corner T. Is done. Such calculation of the curvature radius is performed for each node N, and the recommended vehicle speed corresponding to each curvature radius is set as the recommended vehicle speed of each corresponding node N.
[0042]
Thereafter, in step 113, analysis processing of the vehicle speed introduced into the corner T of the vehicle is performed. In this analysis process, for each node N existing within a predetermined distance forward from the current position X of the vehicle, the vehicle speed at which the vehicle can safely decelerate to the corresponding recommended vehicle speed and the maximum of the vehicle at the current position X is obtained. Each vehicle speed is calculated. The minimum of the maximum vehicle speeds is set as the recommended vehicle speed Vreq at the current position X of the vehicle.
[0043]
Next, the vehicle speed width ΔV is calculated based on the recommended vehicle speed Vreq and the current vehicle speed Vc of the vehicle using the following equation (1).
[0044]
[Expression 1]
ΔV = Vc−Vreq
According to the equation (1), the smaller the vehicle speed width ΔV, the closer the current vehicle speed Vc is to the recommended vehicle speed Vreq. Therefore, it is analyzed that the vehicle can enter the corner T at an appropriate vehicle speed. Conversely, as the vehicle speed width ΔV is larger, the current vehicle speed Vc is far away from the recommended vehicle speed Vreq. Therefore, the vehicle enters the corner T due to excessive speed, and the centrifugal force acting on the vehicle is increased at the corner T. It is analyzed that it becomes larger when the car turns.
[0045]
When the process in step 113 is completed as described above, a travel environment information transmission process is performed in step 120 of FIG. In this process, the information related to the curve start point K determined in the driving environment recognition process routine 110 and the vehicle speed width ΔV with respect to the recommended vehicle speed Vreq when entering the corner T are output to the electronic control unit E.
[0046]
When the microcomputer 50 of the electronic control unit E proceeds to the processing of the damping coefficient ratio setting processing routine 130 (see FIG. 10) while executing the suspension control program according to the flowchart of FIG. It is determined whether or not the vehicle is in corner control execution. Here, executing corner control means that the vehicle is located between the current position X and the escape position from the corner T. Therefore, if the vehicle is not in corner control, the determination in step 131 is NO. On the other hand, if the vehicle is in corner control, the determination in step 131 is YES.
[0047]
If the determination in step 131 is NO as described above, in the next step 132, it is determined whether or not the distance L from the current position X of the vehicle to the curve starting point K is less than a predetermined value. At this stage, if the distance L is not less than the predetermined value, it is determined NO in step 132, and then in step 133, the suspension coefficient S1 is used for the normal running of the vehicle. A setting process common to S4 is performed. The damping coefficient ratio Crate is a ratio of the damping coefficient C to the critical damping coefficient Cc (usually a value within a range of 0.35 to 0.5), and is expressed by the following equation (2).
[0048]
[Expression 2]
Cratio = C / Cc
On the other hand, if the determination in step 132 is YES, the distance L is less than the predetermined value, so that the flag F is set to F = 1 in step 134. Note that F = 0 indicates that the distance L is equal to or greater than a predetermined value.
[0049]
After the processing in step 134, the damping coefficient ratio common to the suspension devices S1 to S4 is set as follows in step 135 on the assumption that the vehicle is in a position immediately before entering the corner T. . Also, if the determination in step 131 is YES and it is determined in step 136 that the vehicle has not passed through the corner T based on the detection output of the gyro sensor 30a from the computer 30f, the determination is NO. The damping coefficient ratio common to the suspension devices S1 to S4 is set as follows.
[0050]
That is, the damping coefficient ratio “Crio” that should be set in common to each of the suspension devices S1 to S4 is set according to data representing the relationship between the vehicle speed width ΔV and the damping coefficient ratio “Crio” (hereinafter referred to as “ΔV-Cratio data”). Is done. Here, the ΔV-Cratio data is set to increase the damping coefficient ratio Crate by increasing the vehicle speed width ΔV, and to decrease the damping coefficient ratio Crate by decreasing the vehicle speed width ΔV.
[0051]
If the vehicle exits from the corner T and is determined YES in step 136 based on the detection output of the gyro sensor 30a from the computer 30f, F = 0 is set in step 137, and in step 138. Similarly to the processing in step 133, a damping coefficient ratio common to the suspension apparatuses S1 to S4 is set.
[0052]
When the processing of the damping coefficient ratio setting processing routine 130 (see FIG. 9) is completed as described above, load input processing is performed in the next step 140. In this load input process, the detection output of the occupant sensor 40a is set in step 140 as the seat load Wa applied to the seating portion 71 of the driver's seat 70a. Further, the detection output of the occupant sensor 40b is set in step 140 as the seat load Wb applied to the right seating portion 72 of the rear seat 70b. Further, the detection output of the occupant sensor 40c is set at step 140 as the seat load Wc applied to the seating portion 73 of the passenger seat 70c. Further, the detection output of the occupant sensor 40d is set in step 140 as the seat load Wd applied to the left seating portion 74 of the rear seat 70d.
[0053]
Next, in the damping coefficient calculation processing routine 150, a damping coefficient (corresponding to the magnitude of the damping force of the suspension device) is calculated according to the riding situation. First, in this damping coefficient calculation processing, the loads W1, W2, W3, and W4 applied to the suspension devices S1, S2, S3, and S4 are based on the vehicle body weight Wm and the seat loads Wa to Wd, respectively, according to the following numbers. It is calculated using equations 3 to 6, respectively. Hereinafter, the loads W1, W2, W3, and W4 are also referred to as suspension loads W1, W2, W3, and W4.
[0054]
[Equation 3]
W1 = Wm / 4 + Wa × K1 + Wb × K2 + Wc × K3 + Wd × K4
[0055]
[Expression 4]
W2 = Wm / 4 + Wa × K2 + Wb × K1 + Wc × K4 + Wd × K3
[0056]
[Equation 5]
W3 = Wm / 4 + Wa × K3 + Wb × K4 + Wc × K1 + Wd × K2
[0057]
[Formula 6]
W4 = Wm / 4 + Wa × K4 + Wb × K3 + Wc × K2 + Wd × K1
Here, the coefficient K1 is a load coefficient considering the same position riding in the automobile. K2 is a load coefficient in consideration of the front-rear symmetrical riding in the automobile. K3 is a load coefficient in consideration of right and left target riding in the automobile. K4 is a load coefficient in consideration of diagonal position riding in the automobile. Note that K1 + K2 + K3 + K4 = 1, and for example, K1 = 0.5, K2 = 0.2, K3 = 0.2, and K4 = 0.1 are set.
[0058]
Accordingly, the damping coefficient C1 of the suspension apparatus S1, the damping coefficient C2 of the suspension apparatus S2, the damping coefficient C3 of the suspension apparatus S3, and the damping coefficient C4 of the suspension apparatus S4 are the damping coefficient ratio Craatio common to the suspension apparatuses S1 to S4. Based on the suspension loads W1 to W4, the following formulas 7 to 10 are used.
[0059]
[Expression 7]
C1 = Cratio × 2 {(W1 / g) × ks}^1/2
[0060]
[Equation 8]
C2 = Cratio × 2 {(W2 / g) × ks}^1/2
[0061]
[Equation 9]
C3 = Cratio × 2 {(W3 / g) × ks}^1/2
[0062]
[Expression 10]
C4 = Cratio × 2 {(W4 / g) × ks}^1/2
Here, ks is a common spring constant in the suspension devices S1 to S4. In each of the equations (7) to (10), the term on the right side excluding the damping coefficient ratio Craatio is a term corresponding to the critical damping coefficient Cc. It is assumed that the critical damping coefficient ratio Craatio is preset to a value within the range of 0.35 to 0.5 described above.
[0063]
When the damping coefficients C1 to C4 are calculated in this way, the throttle opening of the electromagnetic throttle valve 13 of each suspension device S1 to S4 is adjusted so that the damping degree of each suspension device S1 to S4 is the same. Based on the throttle opening degree-damping coefficient data that defines the relationship between the opening degree and the damping coefficient, it is set separately for each damping coefficient. In addition, making the damping degree of each suspension device S1 to S4 the same means making the sliding speed of the piston of the damper of each suspension device S1 to S4 the same.
[0064]
Here, in the throttle opening degree-damping coefficient data, the throttle opening degree of the electromagnetic throttle valve 13 (for example, the throttle opening degree of the electromagnetic throttle valve of the suspension device S1) corresponds to make the degree of attenuation of each suspension device the same. It is set to decrease (or increase) in response to an increase (or decrease) in the damping coefficient (for example, the damping coefficient of the suspension device S1).
[0065]
For example, in the car, when an occupant is in only the seating portion 71 of the driver seat 70a and the left seating portion 74 of the rear seat 70d, the seat load detected by the right seating portion 72 of the rear seat 70b is Wb = Similarly, the seat load detected at the seating portion 73 of the passenger seat 70c is Wc = 0.
[0066]
Here, in the above formulas 3 to 6, the load coefficient K1 having the maximum value among the load coefficients affects only the suspension loads W1 and W4, and the suspension loads W2 and W3 include the load coefficient K2. And only K3. Accordingly, it is understood that the suspension loads W2 and W3 are smaller than the suspension loads W1 and W4 when the values of the load coefficients K1 to K3 described above are taken into consideration.
[0067]
Accordingly, the damping coefficients C1 to C4 are individually determined so as to correspond to the suspension devices S1 to S4 by using the above formulas 7 to 10 from the suspension loads W1 to W4 having the load differences as described above. It is calculated and each throttle opening is determined corresponding to each attenuation coefficient.
[0068]
Incidentally, if the relationship between the damping force and the damping coefficient of each suspension device S1 to S4 is laid, the damping force of each suspension device S1 to S4 is set so that the damping degree of each suspension device is the same. Based on each damping force-damping coefficient data that defines the relationship with the coefficient, the setting is made separately according to each damping coefficient C1 to C4. Here, in the damping force-damping coefficient data, the damping force (for example, the damping force of the suspension device S1) increases the corresponding damping coefficient (for example, the damping coefficient C1) so that the degree of damping of each suspension device is the same. It is set to increase (or decrease) according to (or decrease).
[0069]
When the throttle opening degree of each electromagnetic throttle valve 13 of the suspension devices S1 to S4 is determined as described above, the throttle opening degree of the electromagnetic throttle valve 13 is converted into data in each drive circuit 60a ~ in step 160 of FIG. To 60d.
[0070]
Accordingly, each of the drive circuits 60a to 60d drives each electromagnetic throttle valve 13, and adjusts the throttle opening of each electromagnetic throttle valve 13 to the corresponding set throttle opening. Here, when the determined throttle opening of the electromagnetic throttle valve 13 is small, the flow rate of the hydraulic oil between the hydraulic chambers 12a and 12b of the corresponding damper 10 is reduced, and the degree of attenuation of each suspension device is made the same. Thus, the damping force of the suspension device corresponding to the damper 10 is increased. Conversely, when the determined throttle opening of the electromagnetic throttle valve 13 is large, the flow rate of the hydraulic oil between the hydraulic chambers 12a and 12b of the corresponding damper 10 is increased, and the degree of attenuation of each suspension device is made the same. Thus, the damping force of the corresponding suspension device is reduced.
[0071]
Accordingly, the damping force ratio Crate of the suspension devices S1 to S4, that is, the damping degree is controlled for each suspension device S1 to S4 so that the suspension devices S1 to S4 are all the same. The
[0072]
Accordingly, each suspension device described above is individually controlled with an optimum damping force in accordance with the riding situation of each occupant, and as a result, the handling stability of the vehicle and the riding comfort for each occupant can be improved.
[0073]
In carrying out the present invention, the following various modifications are possible without being limited to the above embodiment.
(1) The suspension load applied to each suspension device S1 to S4 may be detected by a pressure sensor or other various sensors without using the occupant sensors 40a to 40d.
(2) Each suspension load may be calculated from the detection output of a displacement sensor that detects the stroke of the piston 11 provided in each suspension device when the vehicle is stopped. Each suspension load may be calculated from the detection output of a displacement sensor that detects the relative displacement between the unsprung member and the unsprung member.
(3) The target vehicle is not limited to a sedan type automobile, and may be applied to a vehicle having a seat different from a sedan type such as a wagon, a microbus, or a train.
[Brief description of the drawings]
FIG. 1 is a block diagram of an automotive suspension control system according to the present invention.
FIG. 2 is a schematic layout diagram of suspension devices for the automobile.
3 is an enlarged side view of the suspension device of FIG. 2. FIG.
FIG. 4 is an equivalent circuit diagram of a damper of the suspension device.
FIG. 5 is a plan view of the automobile.
6 is a flowchart showing a navigation control program executed by a computer of the navigation apparatus of FIG.
FIG. 7 is a detailed flowchart of the navigation basic processing routine of FIG.
FIG. 8 is a detailed flowchart of a travel environment recognition process routine of FIG.
9 is a flowchart showing a suspension control program executed by the microcomputer of the electronic control device of FIG.
10 is a detailed flowchart showing an attenuation coefficient ratio setting processing routine of FIG.
FIG. 11 is a schematic view of a road including a curved road starting point on which the automobile travels.
[Explanation of symbols]
B ... body, E ... electronic control device, N ... navigation device, T ... corner,
R1, R2 ... Lower arm, S1, S2, S3, S4 ... Suspension device,
30f: Computer, 40a, 40b, 40c, 40d ... Occupant sensor,
50: Microcomputer.

Claims (4)

A suspension device which is interposed between an unsprung member and an unsprung member of a vehicle and which extends and contracts so as to absorb an impact acting between the unsprung member and the unsprung member. ,
A plurality of occupant sensors for detecting loads acting on the respective seats of the plurality of seats of the vehicle;
Based on the detected loads of the plurality of occupant sensors, the load of the sprung member, and the damping coefficient ratio common to the suspension apparatuses, the damping coefficient of the suspension apparatuses is set to the same degree of attenuation of the suspension apparatuses. And a damping coefficient calculating means for calculating each,
A vehicle suspension control system for controlling each suspension device based on each damping coefficient. A shock absorber acting between the unsprung member and the sprung member is interposed between the unsprung member and the unsprung member of the vehicle on which the navigation device is mounted. A suspension device that expands and contracts,
A plurality of occupant sensors for detecting loads acting on the respective seats of the plurality of seats of the vehicle;
Corner determination means for determining whether or not the vehicle is passing through the corner of the travel path based on the travel path information of the vehicle from the navigation device;
When it is determined that the corner determining means is not passing through the corner, a normal driving damping coefficient ratio common to the suspension devices is set, and when the corner determining means determines that the corner is passing, the navigation is performed. A damping coefficient ratio setting means for setting a corner traveling damping coefficient ratio common to the suspension devices based on information representing a speed difference between the current speed of the vehicle from the device and a recommended approach speed for the corner;
Based on the normal driving damping coefficient ratio or corner driving damping coefficient ratio, the detected loads of the plurality of occupant sensors, and the loads of the sprung members, the damping coefficients of the suspension apparatuses are determined by the attenuation of the suspension apparatuses. Attenuation coefficient calculation means for calculating the same degree so as to be the same,
A vehicle suspension control system for controlling each suspension device based on each damping coefficient. The damping coefficient calculation means weights the detected loads so as to make the degree of damping of the suspension devices the same, and sets the weighted loads as the weighted loads, and replaces the weighted loads with the detected loads. 3. The vehicle suspension control system according to claim 1, wherein the suspension control system is used for calculating a damping coefficient. A suspension device which is interposed between an unsprung member and an unsprung member of a vehicle and which extends and contracts so as to absorb an impact acting between the unsprung member and the unsprung member. ,
Suspension load calculating means for calculating a load applied to each suspension device based on a relative displacement between the unsprung member and the sprung member;
Based on each calculated load calculated by the suspension load calculating means, the load of the sprung member, and the damping coefficient ratio common to each suspension apparatus, the damping coefficient of each suspension apparatus is calculated as the degree of attenuation of each suspension apparatus. Attenuation coefficient calculation means for calculating each so as to be the same,
A vehicle suspension control system for controlling each suspension device based on each damping coefficient.

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