JPH04500491A - Undercarriage control device with actuator adjustment circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Undercarriage control device conventional technology with actiniator adjustment circuit The present invention is equipped with a sensor that detects the running state, and the data of the sensor is a vehicle, which is provided in parallel with the device and input to a controller that controls a Y-active damper; In particular, the present invention relates to devices and methods for controlling the chassis of passenger cars and commercial vehicles.

The purpose of controlling a vehicle's chassis is to control the chassis in a way that increases both comfort and driving performance. It is to adjust. Comfort and driving safety are contradictory properties. Toi In order to make it more comfortable, the damper installed in the chassis in parallel with the spring device should be reduced. It is necessary to soften the damping characteristics, and on the other hand, to increase driving safety, it is necessary to harden the adjustment of the chassis. This is because the damping characteristics must be hard.

It is possible to detect the running condition of the vehicle with a predetermined sensor and input the signal to the controller. It is familiar. The controller controls the vehicle's dampers and improves driving comfort in non-hazardous conditions. (soft damping characteristics), while adjusting the damping characteristics to be harder in dangerous conditions. As a result, the adjustment of the chassis is strongly controlled.

There are three different types of dampers in use today. so-called passive A typical damper has a piston-cylinder device, and the cylinder chamber of the piston is vortexed by fluid. It is divided into two cylinder chambers. When the piston moves, it causes The movement of the piston is braked by the discharged medium passing through a certain cross-section of the flow. It will be done.

So-called bioactive dampers have a similar configuration to passive dampers, but with The flow cross section of the sliding cylinder chamber can be varied. This adjusts the damping force. can do.

This adjustment is performed until the damping characteristics change from soft to hard. Furthermore, both So-called active dampers that actively supply pressure medium to the cylinder chamber are known. Ru. Since this damper has to create a corresponding pressure, it must be bioactive. The energy consumption is considerably higher than that of a normal damper. On the contrary Bioactive dampers simply require energy to adjust the flow cross section. Ru.

When developing and designing vehicle control systems, traditional controller configuration and optimization methods are used. I can stay. However, this conventional method applies only to linear devices. Vehicle control A dynamic actuator (usually a large, constant device if a dynamic actuator is used) Since pressure is built up, the flow rate of the pressure medium is dependent on the drive signal obtained from the controller. It becomes linear. This is because the supply valve that supplies the pressure medium has a driving voltage and its opening. This is because there is a linear relationship in the cross section. If a bioactive damper is used, the No setting pressure is used. In addition to the controlled throttle cross-section, the flow rate of the pressure medium is It is related to the pressure difference between cylinder chambers. Therefore, nonlinear components occur, so linear Controller configurations and optimization methods that are available only for the device may not be used. (naru)

Advantages of invention In contrast, in the device according to the invention as defined in claim 1, a bioactive damper is provided. Even when using a controller, the design of chassis control can be done using conventional controller configurations and optimization methods. This has the advantage of being able to do the following. This is placed between the controller and the damper. and adjusts the nonlinear control characteristics of the damper according to the linear control voltage of the controller. This is made possible by a compensation circuit. This allows development and design similar to active devices. It becomes possible to do it. Furthermore, in a bioactive damper, the compensation circuit according to the invention is simply You just need a road.

As already mentioned, the dampers are separated from each other by a damper piston and a compensation circuit are filled with fluids that communicate with each other through the cross-section of the aperture aperture controlled by the driving voltage of It has two cylinder chambers. In that case, According to the equation, the flow rate of fluid passing through the throttle cross section related to the slide position can be determined.

However, Vq (u) is the total flow rate coefficient, and pl is the fluid in one first cylinder chamber. pressure, p2 is the fluid pressure in the other second cylinder chamber, A2 is the fluid pressure in the second cylinder chamber The related piston area, ΔFd, is the amount of change in damping force. Amount of change in damping force △Fd = Input 2 · △p; 1ΔP - P2 - PI.

According to the embodiment of the present invention, the total passing flow coefficient is equal to the leakage flow rate vqO, which is independent of the driving amount. It is formed from the sum of the passing flow coefficient V ql (u), and the flow rate q is Preferably, in order to eliminate the nonlinearity of the first summand in equation (3), A mathematical formula is used in which the amount is proportional to the size of the predetermined amount Ul.

Preferably, said quantity U1 is the control voltage of the controller.

According to a preferred embodiment of the invention, the formula is It is expressed as

As a result of the compensation performed by the compensation circuit (7), according to equation (4), and the driving amount U Insert the maximum value "1" for Ul (slide position U, control voltage and bow) This is derived from equation (5).

When realized by computer, nonlinear compensation is performed. Since the formula is scaled in order to .

drawing The present invention will be described in detail below based on the drawings.

FIG. 1 is a two-mass, one-wheel model diagram of a vehicle with active chassis control.

FIG. 2 is a block diagram of the control circuit.

FIG. 3 is a model diagram of a bioactive damper.

FIG. 4 is a diagram showing the nonlinearity of the control characteristics of the bioactive damper.

In Figure 1, each wheel area of a vehicle equipped with chassis control is illustrated as a two-mass, one-wheel model. ing. The wheel mass mr is applied to the wheel area via a spring device 1 having a spring constant ca. It is combined with the vehicle body mass ma of the vehicle belonging to the area. In parallel with the spring device l An active damper 2 is provided. The damping force Fd can be adjusted via the drive voltage Vd. It is possible to The elastic portion of the wheel is determined by a spring constant cr. The wheels are S The vehicle travels on the road 3 having the irregularities shown. This unevenness S is determined for the inertial frame 4. It will be done. The wheel distance relative to the inertial system 4 is illustrated by Xr. Running path 3 and wheel quality A relative wheel distance Xrr occurs between the amount mr. Furthermore, wheel mass rnr and vehicle body mass ma A relative spring displacement amount Xar is formed in between. The vehicle body mass nla is the distance in the inertial frame 4. It has a distance Xa (vehicle body distance).

The dynamic running state of the vehicle is detected by sensors installed on the vehicle body and wheel supports. It will be done. FIG. 2 shows the sensor 5 connected to the controller 6 as a block diagram. There is. The controller 6 is connected to the bioactive damper 2 via a compensation circuit 7 according to the invention. . As the input quantity of the controller 6, for example, the damping force Fd determined by the sensor, the relative spring Displacement fiXa+, wheel acceleration Xr, and vehicle body acceleration Xa are used. displacement amount The conventional method is to convert velocity to acceleration, or vice versa. This can be done by differentiation or integration using the method.

FIG. 3 shows a model of a bioactive damper 2. In FIG.

The bioactive damper is divided by the piston 9 into two cylinder chambers 10.11. It has a cylinder 8. A gas chamber is provided in the upper part of the cylinder chamber IO by a separation piston 12. 13 is formed. The volume of this gas chamber is V, and a pressure P Gas is applied. Balancing the volume. The damper 2 has an elastic support portion 14 having a spring constant cg. It is connected to the vehicle chassis via. The elastic support 14 has a distance of X.

The upper first cylinder chamber 10 has a fluid (eg oil) pressure p1. Further The cylinder chamber 10 of No. 1 has a hydraulic capacity C1 and has an area A1 on the piston 9 side. Ru. The lower cylinder chamber 11 also has a pressure p2 and a hydraulic capacity C2. That piss The cross-sectional area of the ton surface can be controlled by applying a driving voltage Vd, Thereby, the flow rate q of the fluid passing through the cross section of the aperture opening can be changed. good Preferably, to displace the aperture 15, a secondary system (encircled by the block in Fig. 3) is used. ) can be described by the position side 81! Using a magnetic actuator device I can do it. The sliding position U of the aperture 15 is driven via an electromagnetic actuator device. It can be displaced by voltage Vd. In that case, the total flow rate coefficient of the throttle 15 is There is no linear relationship with the id position 11u.

This nonlinearity is illustrated in FIG. As a result, the control circuit for undercarriage control Therefore, conventional controller configurations and optimization methods cannot be used. Because these are This is because it is effective for linear devices. In the present invention, this nonlinearity is compensated for using a compensation circuit. 7, the bioactive damper 2 used here It becomes possible to use the conventional controller configuration and optimization method for J.

An equation for the flow rate q can be obtained from the model of the damper 2 described above. However, ΔFd decreases This is the amount of change in damping force. For this ΔFd = Enter, ・Δp; Mp"p2-pl・ A relationship exists.

As is clear from Figure 4, the characteristic curve does not deviate from the zero point of the coordinate system, and there is no leakage into the fluid. amount is occurring. This leakage flow rate VqO is unrelated to the drive amount (slide position U). It becomes quantity. A formula that takes this relationship into account is used for the total flow rate coefficient Vq(u). It will be done. That is, VQ(u)=VqO+Vql(u). Substituting this relationship into equation (2) Then, the relationship is obtained. However, VqO is the leakage flow coefficient and Vql is the passing flow coefficient. be.

In the conventional controller configuration and optimization method described above, a multivariable controller (controller 6) A linear controlled object model is required to calculate the control coefficients. In contrast, the aperture It can be seen that equation (3) has a nonlinear relationship. The present invention aims to solve this problem. Since nonlinear compensation is performed in , the first summand of equation (3) is linearly similar to relationship, i.e. is obtained.

This causes the flow rate to be proportional to the magnitude of the quantity U1, which will be explained in detail later. child The quantity is the control voltage Ul (output voltage of the controller 6). The direction of fluid flow is determined by the damping force. It is determined by the direction of change ΔFd. In the above equation, we use the bioactive dunnoku. In this case, the direction of the flow becomes the direction of the change in damping force ΔFd at that time, resulting in L). It is a premise.

To determine what kind of nonlinear compensation to perform, solve equation (4) for Vql (u). It is recognized by this. That is, becomes. Comparing Equation (3) and Equation (5), you can see that the nonlinearity is gone. It becomes clear. That is, since the contents of the square root are in the numerator on the one hand and in the denominator on the other hand, , because they cancel each other out.

By inserting the maximum value rlJ into the drive amount U or Ul, the formula ( 5) Can be intertwined. In other words, a computer is used to realize nonlinear compensation. When using , equation (5) is scaled. As a result, the calculation range is exceeded. You can avoid it. In that case, it will be done according to the law. That is, the formula (6 ) is substituted into equation (5), and the damping force change ΔFd is scaled to obtain the relationship ΔFd. Replaced by +a-Fd.

Next, the entire equation is related to the maximum flow rate Vql (1). The formula is obtained It will be done.

Solving the scaled equation (7) for the quantity U yields. leakage flow coefficient The VqO1 passing flow coefficient VQI and the maximum fluid flow rate depend on the damper parameters used. This is known as a ta. For these values, the Dan A used in the experiment has this value. The following table is obtained for the well-rescaled backflow curve.

The flow rate q of a bioactive device is given by equations (3) and (4).

When using an active damper instead of a bioactive damper, for the flow rate q: Linear relationship below holds true.

It can be seen that the direction of the flow rate q is completely unrelated to the damping force.

In active devices, energy is therefore removed or supplied. Ul If the signs of and ΔFd are the same, then equation (3) and equation (9) have identity. exists. In other words, it is an active device to which conventional controller configurations and optimization methods can be applied. means that it can be replaced by bioactive equipment in this operating area. do.

In other regions, both equations (3) and (9) cannot be matched. In this case, The damper can be fully closed or fully open, allowing The power conversion in the active device is therefore as small as possible. The difference can be made as small as possible.

international search report -m--1--1 PCT/DE 90100401SA 37200

Claims (1)

[Claims] 1) Equipped with a sensor that detects the running condition, and the sensor data is transmitted to the spring device. A vehicle, especially a passenger vehicle, input to the controller that controls the semi-active dampers that cooperate The non-glandular control feature of the damper (2) is used in a device for controlling the chassis of commercial vehicles. A compensation circuit (7) that adjusts the linear control voltage of the controller (6) 6) and a damper (2). 2) The dampers (2) are separated from each other by a damper piston (9) and connected to a compensation circuit (7). ), which are controlled by the drive voltage (Vd) of the The body has two grooved cylinder chambers (10, 11), and Vq(u) is completely passed through. quantity coefficient, p1 is the fluid pressure in one first cylinder chamber (10), and p2 is the other first cylinder chamber (10). The fluid pressure in the second cylinder chamber (11), A2, is related to the second cylinder chamber (11). ΔFd is the piston area, and ΔFd is the change in damping force (ΔFd≒A2・Δp, Δp=p2− As p1), there are ▲ mathematical formulas, chemical formulas, tables, etc. ▼ [1] ▲ mathematical formulas, chemical formulas, tables, etc. There is a 2. The device according to claim 1, wherein the flow rate q of the fluid is determined. 3) The total passing flow coefficient (Vq(u)) is in communication with the leakage flow rate (Vq0), which is unrelated to the driving amount. It is formed from the sum of overflow coefficients (Vq1), and the flow rate (q) is ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Claim No. 3 characterized by The device according to item 1 or 2. 4) In order to eliminate the nonlinearity of the first summand of equation (3), the flow rate of the pressure medium is set to a predetermined amount. A claim characterized in that a mathematical formula proportional to the magnitude of (U1) is used. The device according to any one of the items 1 to 3 below. 5) Claim characterized in that said quantity (U1) is a control voltage of a controller (6). The device according to any one of the items 1 to 4 below. 6) If the above formula is the maximum flow rate, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Claims characterized by being expressed in [4] The device according to any one of the ranges 1 to 3. 7) Result of compensation performed by compensation circuit (7) According to formula (4) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Claim No. 1 characterized by [5] The device according to any one of items 1 to 6. 8) Maximum damping force (■d) for the amount of change in damping force (ΔFd), and driving amount (u , U1), the maximum flow rate (■ ) in any one of claims 1 to 9, The device described. 9) The equation is scaled by a computer to perform nonlinear compensation. The device according to any one of claims 1 to 8, characterized in that Place.