Control device and control method

Abstract

Even if the number of independently controllable actuators is less than the number of control axes of the vehicle movement, an effective control is possible.SOLUTION: A control device is a control device that is mounted on a vehicle including one or more actuators capable of independent control and realizes control related to a plurality of control axes larger in number than the number of actuators, the control device including a combined control command amount generation unit that combines, for each actuator, a plurality of control demand amounts that are control amounts demanded for each control axis to generate a control command amount for the actuator, wherein the combined control command amount generation unit prioritizes a specific frequency component for each control axis.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a control device and a control method. [Background technology]

[0002] Generally, vehicle motion can occur in six components: longitudinal, lateral, yaw, vertical, pitch, and roll. It is known that the vehicle's attitude can be controlled by controlling one of six control axes corresponding to these six components. Patent Document 1 discloses a vehicle control device that includes: a head sway prediction model that determines a change in the head sway of an occupant in a first direction caused by vehicle motion in a second direction different from the first direction; and a vehicle motion generation unit that generates vehicle motion based on the head sway prediction model. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-128661 Summary of the Invention [Problem to be solved by the invention]

[0004] The invention described in Patent Document 1 leaves room for improvement in the processing when the number of independently controllable actuators is less than the number of control axes of vehicle motion. [Means for solving the problem]

[0005] A control device according to a first aspect of the present invention is mounted on a vehicle having one or more independently controllable actuators, and realizes control over a plurality of control axes, the number of which is greater than the number of the actuators. The control device includes a composite control command amount generator for each of the actuators that generates a control command amount for the actuator by combining a plurality of control request amounts, which are control amounts required for each of the control axes, and the composite control command amount generator prioritizes a specific frequency component for each of the control axes. A control method according to a second aspect of the present invention is a control method executed by a control device that includes one or more independently controllable actuators and controls a plurality of control axes, the number of which is greater than the number of the actuators, and includes a composite control command amount generation step of generating a control command amount for each of the actuators by combining the plurality of control request amounts, and in the composite control command amount generation step, prioritizing a specific frequency component for each of the control axes. [Effects of the Invention]

[0006] According to the present invention, even when the number of independently controllable actuators is less than the number of control axes of vehicle motion, effective control is possible. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a plan view showing a schematic configuration of a vehicle; [Figure 2] A diagram showing the force and moment acting on the center of gravity of the vehicle due to the driving force and driving force reaction force. [Figure 3] A diagram showing the relationship between typical actuators installed in a vehicle, the number of control inputs, and the controllable vehicle motion components. [Figure 4] Functional block diagram of a control device according to a first embodiment [Figure 5] A diagram showing how the human body responds to vibrations [Figure 6] Functional block diagram of a control device according to a second embodiment [Figure 7] Conceptual diagram showing the relationship between control command amount and control demand amount [Figure 8]Schematic diagram showing the behavior of a vehicle in a comparative example [Figure 9] FIG. 2 is a schematic diagram showing the behavior of a vehicle according to the present embodiment; [Figure 10] Diagram showing the mechanism by which pitch fluctuations cause vertical vibrations for the driver [Figure 11] Functional block diagram of a control device according to a third embodiment [Figure 12] FIG. 10 is a schematic diagram showing frequency division in the fourth embodiment; [Figure 13] Functional block diagram of a control device according to a fourth embodiment [Figure 14] FIG. 22 is a schematic diagram showing frequency division in a first modification of the fourth embodiment; [Figure 15] Functional block diagram of a control device according to a first modification of the fourth embodiment. [Figure 16] FIG. 13 is a schematic diagram illustrating the difference in response between braking / driving force and lateral force in a second modification of the fourth embodiment; [Figure 17] FIG. 22 is a schematic diagram showing frequency division in a second modification of the fourth embodiment; [Figure 18] Functional block diagram of a control device according to a second modification of the fourth embodiment. [Figure 19] FIG. 13 is a schematic diagram showing frequency division in the fifth embodiment; [Figure 20] Functional block diagram of a control device according to a fifth embodiment [Figure 21] FIG. 13 is a schematic diagram showing frequency division in the sixth embodiment; [Figure 22] Functional block diagram of a control device according to a sixth embodiment [Figure 23] Functional block diagram of a control device according to a seventh embodiment [Figure 24] Functional block diagram of a control device according to an eighth embodiment [Figure 25] Control device hardware configuration diagram DETAILED DESCRIPTION OF THE INVENTION

[0008] (Example of vehicle configuration) The forces acting on a vehicle will be described with reference to Figures 1 and 2. Figure 1 is a plan view showing a schematic configuration of a vehicle 1. Note that Figure 1 includes a control device 100, which will be explained in each embodiment below, but not all embodiments are premised on the same configuration as the vehicle 1. In particular, the actuators provided on the vehicle differ depending on the embodiment.

[0009] The vehicle 1 includes a vehicle momentum sensor 3, an accelerator pedal 4, a brake pedal 5, a steering wheel 6A, a steering mechanism 6B, an in-wheel motor 7, tires 8, and a controller area network 9 connecting the various devices. The in-wheel motor 7 is a collective term for a left front motor 7FL, a right front motor 7Fr, a left rear motor 7RL, and a right rear motor 7Rr. The tires 8 are a collective term for a left front tire 8FL, a right front tire 8Fr, a left rear tire 8RL, and a right rear tire 8Rr. However, FIG. 1 only clearly shows the configuration necessary for explaining this embodiment, and the vehicle 1 may actually include additional configuration not described here.

[0010] In addition, the coordinate system used in the description has the x-axis representing the front-to-rear direction of the vehicle 1, the y-axis representing the left-to-right direction, and the z-axis representing the up-to-down direction. The positive direction of the x-axis is the forward direction of the vehicle 1, the positive direction of the y-axis is the left direction, and the positive direction of the z-axis is the up direction. The vehicle 1 is driven by each in-wheel motor 7 generating a driving force based on input from the accelerator pedal 4. Each in-wheel motor 7 can independently generate driving torque and braking torque. Note that the driving method of the vehicle 1 covered by this embodiment is not limited to in-wheel motors 7, and the vehicle may be driven by a motor or engine mounted on the vehicle body as a driving device. The traveling direction of the vehicle 1 is changed by the steering mechanism 6B turning the front wheels in reference to input from the steering wheel 6A. Braking of the vehicle 1 is achieved by generating a braking force in the in-wheel motor 7 of each wheel in reference to the brake pedal 5. Note that a friction brake (not shown) is used or combined with other brakes to deal with areas that cannot be controlled by each in-wheel motor 7.

[0011] FIG. 2 shows the force and moment that the driving force and driving force reaction force exert on the center of gravity of the vehicle 1. The driving force generated by the tires 8 when braking and driving the vehicle 1 acts not only in the front-rear direction of the vehicle 1, but also in the up-down direction due to the driving force reaction force. The driving force of the front wheels F xf , rear wheel drive force F xr The front wheel suspension angle, which is the angle between the horizontal plane and the line connecting the center of the front wheel axle and the center of rotation of the suspension, is θ f The rear wheel suspension angle, which is the angle between the horizontal plane and the line connecting the rear wheel axle center and the suspension rotation center, is θ r In this case, when a driving force is applied to the front and rear wheels, the driving reaction force in the vertical direction of the front wheels is F xr tanθ f and the driving reaction force in the vertical direction of the rear wheels is F xr tanθ r is.

[0012] In the case of an in-wheel motor, θf and θr are the angles formed by the horizontal plane and a line connecting the tire's contact point and the suspension's rotation center, rather than the angle formed by the horizontal plane and a line connecting the axle center and the suspension's rotation center. However, even in this case, only the magnitude of the driving force reaction force changes; the driving force reaction force is still generated in the vertical direction.

[0013] (General theory on six-degree-of-freedom vehicle motion control) The six components that can occur at the center of gravity of vehicle 1, namely the longitudinal, lateral, yaw, vertical, pitch, and roll directions, are collectively referred to as the "six components of vehicle motion." Each of these six components is also called a "control axis." The influence of the driving forces of the front left wheel, front right wheel, rear left wheel, and rear right wheel on the five-directional motion, excluding the lateral motion, from the six components of vehicle motion, is expressed by the following equation 1.

[0014]

number

[0015] where Fx : Force applied in the longitudinal direction of vehicle 1, M z : Yaw moment, F z : Force applied in the vertical direction, M y : Pitch moment, M x These are usually calculated by a higher-level controller and passed to a lower-level controller as target values ​​of the force and moment to be applied to the center of gravity of the vehicle 1. In the lower-level controller, F xfl : Braking and driving force of the front left wheel, F xfr : Braking / driving force of the front right wheel, F xrl : Braking and driving force of the rear left wheel, and F xrr : The braking / driving force of the front right wheel is calculated. The braking / driving force is a concept that combines braking force and driving force, and for example, a positive value indicates a force that moves the vehicle 1 forward, and a negative value indicates a force that moves the vehicle 1 backward. The lower-level controller calculates the force and moment to be applied to the center of gravity of the vehicle 1, i.e., F x , M z , F z , M y , and M x , and calculate the magnitude of the driving force of each tire wheel to generate those forces and moments at the center of gravity of vehicle 1. The following are constants specific to vehicle 1, and l f : Distance from the front axle to the center of gravity, l r : Distance from rear axle to center of gravity, t f : Front wheel tread, t r :Rear wheel tread.

[0016] Here, F on the right side of Equation 1 xfl , F xfr , F xrl , and F xrrare called control inputs. Therefore, the number of control inputs, which means the number of control inputs, is four in Equation 1. Equation 1 shows that, in principle, it is possible to control the same number of vehicle motion components as the number of control inputs. The reason for this is that if Equation 1 is considered as a system of simultaneous equations, the control inputs correspond to the unknowns and the vehicle motion components correspond to the number of equations. For example, if the number of vehicle motion components to be controlled is greater than the number of control inputs, the number of equations to be satisfied will be greater than the unknowns, and no control input exists that satisfies all of the equations.

[0017] (Relationship between representative actuators and number of control inputs) Figure 3 is a diagram showing, as a general matter, the relationship between typical actuators mounted on a vehicle, the number of control inputs, and controllable vehicle motion components. However, each vehicle shown in Figure 3 is different from vehicle 1 shown in Figure 1. The names written at the top of Figure 3 are for convenience of explanation.

[0018] Vehicle C11 shown on the far left is a vehicle in which two front wheels connected by an axle 803 and a differential gear 802 that is not actively controlled are driven by a motor 801. A vehicle equipped with a differential gear 802 that is not actively controlled does not actively generate different driving forces on the left and right wheels, and outputs driving forces of the same magnitude on the left and right wheels when traveling straight. In this case, only one control input can be applied to the vehicle. This is because, although driving forces that can be applied to the vehicle are on the front right wheel and the front left wheel, they can only be driven by the same magnitude and cannot be driven independently.

[0019] In C11, there are three controllable vehicle motions: forward / backward, up / down, and pitch. Because the driving forces of the front left and right wheels are equal, no yaw moment or roll moment is generated, and as a result, control in the yaw and roll directions is not possible. Therefore, a vehicle with this configuration has one control input but three controllable vehicle motion components, which is an insufficient number of control inputs for the controllable vehicle motion components. Although not shown in Figure 3, the same applies when a similar configuration is used with two rear wheels driven.

[0020] C23 shows a case where an in-wheel motor 805 is used for driving. C24 shows a case where a differential gear 806 connecting the left and right wheels is actively controlled. C25 shows a case where an active suspension 807 is installed on the rear left wheel. The active suspension 807 is an actuator that generates force only in the vertical direction. C32 and C33 show cases where lateral force is generated in the tires by steering. C41 shows a case where in-wheel motors are installed on all four wheels. Note that the positions and number of actuators shown in Figure 3 are not limited to the method shown in Figure 3, and they may be installed in any positions and in any number.

[0021] -First embodiment- A first embodiment of a control device and a control method will be described below with reference to Fig. 4. In the first embodiment, a controller will be described for a case where there is one control input and three vehicle motion components that can be controlled by an actuator. That is, the vehicle configuration in this embodiment corresponds to C11 in Fig. 3. In this case, the control input is a driving force that is generated on the left and right front wheels with equal magnitudes, so there is one control input, and the controllable vehicle motion components are three components in the longitudinal direction, the vertical direction, and the pitch direction.

[0022] FIG. 4 is a functional block diagram of the control device 100 in the first embodiment. The control device 100 receives as input the accelerator position, brake position, and vehicle momentum. The accelerator position is a signal output by a sensor that measures the depression amount of the accelerator pedal 4. The brake position is a signal output by a sensor that measures the depression amount of the brake pedal 5. The vehicle momentum is the output of a sensor, such as an inertial sensor, mounted on the vehicle 1, and includes the current longitudinal acceleration, current vertical acceleration, and current pitch angular acceleration of the vehicle 1. The output of the control device 100 is a time-series torque command value for the drive motor 130.

[0023] Control device 100 includes a target signal calculation unit 101-0 and a composite control command generation unit 140-0. Target signal calculation unit 101-0 includes a longitudinal target state quantity calculation unit 101, a vertical target state quantity calculation unit 102, a pitch target state quantity calculation unit 103, a longitudinal force calculation unit 104, a vertical force calculation unit 105, and a pitch moment calculation unit 106. Composite control command generation unit 140-0 includes a control demand quantity calculation unit 149 and a control value synthesis unit 143. Control demand quantity calculation unit 149 includes a first braking / driving torque calculation unit 107, a second braking / driving torque calculation unit 108, a third braking / driving torque calculation unit 109, a first filter 110, a second filter 112, and a third filter 113.

[0024] The accelerator position and brake position are input to the longitudinal target state quantity calculation unit 101, which outputs a longitudinal target state quantity to the longitudinal force calculation unit 104. A correspondence table is stored in advance in the longitudinal target state quantity calculation unit 101, and the longitudinal target state quantity corresponding to the input accelerator position and brake position is calculated. The longitudinal target state quantity is a target state quantity in the longitudinal direction of the vehicle 1. For example, the longitudinal target state quantity is +0.1 G corresponding to the depression amount of the accelerator pedal 4.

[0025] The vertical target state quantity calculation unit 102 and the pitch target state quantity calculation unit 103 do not receive any input from outside the control device 100. The vertical target state quantity calculation unit 102 sets the vertical target state quantity to zero and outputs it to the vertical force calculation unit 105. The pitch target state quantity calculation unit 103 sets the pitch target state quantity to zero and outputs it to the pitch moment calculation unit 106. The longitudinal target state quantity is input to the longitudinal force calculation unit 104 from the longitudinal target state quantity calculation unit 101, and the current longitudinal acceleration is input from the vehicle momentum sensor 120.

[0026] The longitudinal force calculation unit 104 calculates the difference between the longitudinal target state quantity and the current longitudinal acceleration, and outputs the result to the first braking / driving torque calculation unit 107. The vertical force calculation unit 105 receives the vertical target state quantity from the vertical target state quantity calculation unit 102 and the current vertical acceleration from the vehicle momentum sensor 120. The longitudinal force calculation unit 104 calculates the difference between the vertical target state quantity and the current vertical acceleration, and outputs the result to the second braking / driving torque calculation unit 108. The pitch target state quantity from the pitch target state quantity calculation unit 103 and the current pitch from the vehicle momentum sensor 120 are input to the pitch moment calculation unit 106. The longitudinal force calculation unit 104 calculates the difference between the pitch target state quantity and the current pitch, and outputs the result to the third braking / driving torque calculation unit 109. The outputs of the longitudinal force calculation unit 104, the vertical force calculation unit 105, and the pitch moment calculation unit 106 are also referred to as "target signals." The target signals are time-series target values ​​for each control axis.

[0027] First braking / driving torque calculation unit 107 calculates a torque command value (hereinafter referred to as the "first torque command value") required to realize the longitudinal acceleration input from longitudinal force calculation unit 104. Second braking / driving torque calculation unit 108 calculates a torque command value (hereinafter referred to as the "second torque command value") required to realize the vertical acceleration input from vertical force calculation unit 105. Third braking / driving torque calculation unit 109 calculates a torque command value (hereinafter referred to as the "third torque command value") required to realize the pitch moment input from pitch moment calculation unit 106.

[0028] The first filter 110 applies a filter that extracts specific frequency components to the first torque command value to calculate a first filtered torque command value. The second filter 112 applies a filter that extracts specific frequency components to the second torque command value to calculate a second filtered torque command value. The third filter 113 applies a filter that extracts specific frequency components to the third torque command value to calculate a third filtered torque command value. However, the frequencies extracted by each filter are arbitrary. For example, they may be set in advance by an operator or may be set randomly.

[0029] For example, the first filter 110 is a low-pass filter that extracts frequencies between 0 and 10 Hz, the second filter 112 is a band-pass filter that extracts frequencies between 10 and 20 Hz, and the third filter 113 is a high-pass filter that extracts frequencies above 20 Hz. The processing of each filter can also be described as "giving priority to specific frequency components" or "applying predetermined frequency characteristics." The frequency band extracted by the first filter 110 is preferably far from the resonance frequencies in the vertical and pitch directions of the vehicle 1. This is to reduce the impact of torque control in the longitudinal direction on the vertical and pitch directions. The frequency band extracted by the second filter 112 is preferably far from the resonance frequencies in the pitch and longitudinal directions of the vehicle 1. The frequency band extracted by the third filter 113 is preferably far from the resonance frequencies in the longitudinal and vertical directions of the vehicle 1.

[0030] Hereinafter, the outputs of the filters, specifically the first filtered torque command value, the second filtered torque command value, and the third filtered torque command value, will be referred to as the "control demand amount." The control value synthesis unit 143 synthesizes the outputs of the filters. In other words, the control value synthesis unit 143 synthesizes the control demand amount for each control axis. Hereinafter, the output of the control value synthesis unit 143 will be referred to as the "control command amount." A value obtained by synthesizing the first filtered torque command value, the second filtered torque command value, and the third filtered torque command value, which are the control demand amounts, is input to the drive motor 130.

[0031] According to the first embodiment described above, the following advantageous effects can be obtained. (1) The vehicle 1 is equipped with one or more independently controllable actuators. The control device 100 is mounted on the vehicle 1 and realizes control of a plurality of control axes, the number of which is greater than the number of actuators. The control device 100 is equipped with a composite control command generator 140-0 that generates a control command for each actuator by combining a plurality of control demands, which are control amounts required for each control axis. The composite control command generator 140-0 prioritizes a specific frequency component for each control axis. Therefore, even if the number of independently controllable actuators is less than the number of control axes for vehicle motion, effective control is possible.

[0032] (2) The control device 100 includes a target signal calculation unit 101-0 that calculates a target signal, which is a time-series target value, for each control axis. The combined control command generation unit 140-0 includes a control demand calculation unit 149 that calculates, for each control axis, a time-series actuator drive torque that prioritizes specific frequency components based on frequency characteristics predetermined for the target signal and each control axis, as a control demand, and a control value combination unit 143 that generates a control command by combining, for each actuator, the control demands for each control axis.

[0033] (3) The control demand calculation unit 149 calculates the drive torque corresponding to the target signal, and each filter applies a frequency characteristic predetermined for each control axis to the drive torque to calculate the control demand.

[0034] (4) The control request amount calculation unit 149 applies frequency characteristics using one of a low-pass filter, a high-pass filter, a band-pass filter, and a band-stop filter.

[0035] (5) The actuator is an in-wheel motor provided on a wheel of the vehicle.

[0036] --Second embodiment-- A second embodiment of a control device and a control method will be described with reference to Figures 5 to 10. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the first embodiment. This embodiment differs from the first embodiment mainly in that the allocation of frequencies of vehicle motion components is determined based on human perception characteristics.

[0037] (Human vibration sensation) Figure 5 is a diagram illustrating how the human body perceives vibration, as described in Japanese Industrial Standards (JIS) C1510. This diagram, however, is a modified version of publicly available data (https: / / kikakurui.com / c1 / C1510-1995-01.html) for the purposes of explaining this embodiment. According to this description, humans are more sensitive to horizontal vibrations than vertical vibrations at frequencies below approximately 3 Hz, and are more sensitive to vertical vibrations than horizontal vibrations above this frequency. If the vehicle motion components of fore-and-aft, up-and-down, and pitch are classified based on the aforementioned human vibration sensation, horizontal vibrations are fore-and-aft, and vertical vibrations are up-and-down and pitch. The reason pitch is classified as vertical vibration will be explained in detail later. The frequency boundary that can be seen from Figure 5 is approximately 3 Hz, but for simplicity, the following description will use 3 Hz. In practice, it may be 2.5 Hz or 4 Hz.

[0038] 6 is a functional block diagram of a control device 100A according to the second embodiment. The control device 100A includes a longitudinal target state quantity calculation unit 101, a vertical target state quantity calculation unit 102, a longitudinal force calculation unit 104, a vertical force calculation unit 105, and a composite control command quantity generation unit 140. The composite control command quantity generation unit 140 includes a one-side frequency processing unit 141, an other-side frequency processing unit 142, and a control value synthesis unit 143. Hereinafter, the one-side frequency processing unit 141 and the other-side frequency processing unit 142 will be collectively referred to as the "control request quantity calculation unit."

[0039] One-side frequency processing section 141 includes a first braking / driving torque calculation section 107 and an LPF 1411. The other-side frequency processing section 142 includes a second braking / driving torque calculation section 108 and an HPF 1421. It can also be said that control device 100A includes LPF 1411 instead of first filter 110, and HPF 1421 instead of second filter 112. The processing of longitudinal target state quantity calculation section 101, vertical target state quantity calculation section 102, longitudinal force calculation section 104, vertical force calculation section 105, first braking / driving torque calculation section 107, and second braking / driving torque calculation section 108 is the same as in the first embodiment, and therefore description thereof will be omitted.

[0040] LPF 1411 is a low-pass filter that targets longitudinal motion, which is horizontal motion, among the vehicle motion components, and extracts frequency components of 3 Hz or less. In this embodiment, the input to LPF 1411 is represented by Tx, and the output of LPF 1411 is represented by Txl. HPF 1421 is a high-pass filter that targets up-and-down motion, which is vertical motion, among the vehicle motion components, and extracts frequency components of 3 Hz or more. In this embodiment, the input to HPF 1421 is represented by Tz, and the output of HPF 1421 is represented by Tzh. Control value synthesis unit 143 synthesizes the output of one-side frequency processing unit 141 and the output of the other-side frequency processing unit 142, i.e., Txl and Tzh, and outputs the result to drive motor 130.

[0041] Figure 7 is a conceptual diagram showing the relationship between the control command amount and the control demand amount. The horizontal axis represents time, and the vertical axis represents the magnitude of the command value. First, the longitudinal torque command value will be described. The longitudinal torque command value before applying the LPF 1411 contains both low-frequency and high-frequency signals. Therefore, if we measure the longitudinal torque command value for a certain period of time before applying the LPF 1411 and observe the resulting time waveform, we see a waveform in which low-frequency components with slow signal fluctuations and high-frequency components with fast signal fluctuations overlap. On the other hand, for the longitudinal torque command value after applying the LPF 1411, the LPF 1411 removes the high-frequency components from the torque command value, thereby removing the fast-fluctuation parts of the signal. Therefore, if we measure the longitudinal torque command value for a certain period of time after applying the LPF 1411 and observe the resulting time waveform, we can see a slow waveform containing only slow-fluctuation components. This slow waveform is the longitudinal torque command waveform shown on the left of Figure 7.

[0042] Next, we will explain the torque command value in the vertical direction. The torque command value in the vertical direction before applying the HPF 1421 contains both low-frequency and high-frequency components, just as before. On the other hand, the torque command value in the vertical direction after applying the HPF 1421 has the low-frequency components removed from the torque command value, and its time waveform becomes a jagged waveform with rapid fluctuations, as shown on the left side of Fig. 7.

[0043] The final torque command value is the sum of the torque command value in the forward / backward direction after application of the LPF 1411 and the torque command value in the upward / downward direction after application of the HPF 1421. Therefore, when checking the time waveform of the final torque command value, it has a shape obtained by adding the slowly changing torque command value in the forward / backward direction to the rapidly changing, jagged waveform of the torque command value in the upward / downward direction.

[0044] FIG. 8 is a schematic diagram showing the behavior of the vehicle 1 when two torque command values ​​are simply added together as a comparative example. Tx brings the vehicle behavior closer to the target value in the longitudinal direction, but at the same time, it has an unintended effect on the vehicle behavior in the vertical direction. The same is true for Tz. Tz brings the vehicle behavior closer to the target value in the vertical direction, but at the same time, it also has an effect on the vehicle behavior in the longitudinal direction. Thus, simply adding up the respective torque command values ​​poses a problem.

[0045] FIG. 9 is a schematic diagram illustrating the effects of this embodiment. In the frequency range below approximately 3 Hz, only Tx is applied to achieve the target value in the longitudinal direction, while in the frequency range above approximately 3 Hz, only Tz is applied to achieve the target value in the vertical direction. With this configuration, Tx, which controls the longitudinal direction of the vehicle 1, is effective only in the low frequency range, and Tz, which controls the vertical direction of the vehicle 1, is effective only in the high frequency range. This configuration controls one or more vehicle motion components, specifically two, as the number of control inputs, while offering the following advantages: That is, by prioritizing and controlling only vibrations in directions to which humans are sensitive according to the frequency band, deviation from the target value due to interference from the control of other components can be prevented, and vibrations that the driver finds strange or uncomfortable can be reduced.

[0046] (Why pitch and roll are considered vertical vibrations) The classification based on human vibration sensation can be extended to six degrees of freedom of vehicle motion, because the horizontal vibration felt by the driver can be considered as the fore-and-aft, lateral, and yaw movements in the vehicle motion, and the vertical vibration felt by the driver can be considered as the up-and-down, pitch, and roll movements in the vehicle motion.

[0047] Figure 10 shows the mechanism by which pitch fluctuations cause vertical vibrations for the driver. When a pitch angle fluctuation occurs in the vehicle, vertical vibrations occur at the driver's position. The same is true for roll. Therefore, pitch angle and roll angle fluctuations can be considered as vertical vibrations.

[0048] According to the second embodiment described above, the following advantageous effects can be obtained. (6) The frequency characteristics are realized by a high-pass filter and a low-pass filter with a threshold frequency based on human perception, specifically, a cutoff frequency set to approximately 3 Hz. The composite control command generator 140 applies a low-pass filter when the control axes are longitudinal and yaw, and a high-pass filter when the control axes are vertical, pitch, and roll. Therefore, by prioritizing and controlling only vibrations in directions to which humans are sensitive according to the frequency band, deviation from the target value due to interference from the control of other components can be prevented, and vibrations that the driver finds strange or uncomfortable can be reduced.

[0049] (Modification 1 of the second embodiment) In this embodiment, LPF 1411 and HPF 1421 are applied after torque calculation, but they may be substituted by changing the weight for each frequency when calculating the control request amount. For example, the output of first braking / driving torque calculation unit 107 may be frequency analyzed and decomposed into frequency components, and the amplitude of waves having frequencies of 3 Hz or higher may be reduced, for example to zero, to replace LPF 1411. Furthermore, combined control command amount generation unit 140 may use an IIR filter or FIR filter instead of a low-pass filter or high-pass filter.

[0050] (Modification 2 of the second embodiment) In the second embodiment, when there is one control input, the vehicle 1 is controlled in the longitudinal direction and the vertical direction, but the vehicle 1 may be controlled in the longitudinal direction and the pitch simultaneously.

[0051] -Third embodiment- A third embodiment of a control device and a control method will be described with reference to FIG. 11. In the following description, the same components as those in the second embodiment are given the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the second embodiment. This embodiment differs from the second embodiment mainly in that vehicle motion is grouped from the perspective of ride comfort. Specifically, this is as follows.

[0052] In the second embodiment, focusing on the fact that a person's vibration sensation differs between the horizontal and vertical directions, vehicle motion is classified into a first group in the horizontal direction (forward / backward, lateral, yaw) and a second group in the vertical direction (up / down, pitch, roll). In this embodiment, vehicle motion is grouped from the perspective of operability and ride comfort of the vehicle 1. That is, vehicle motion is divided into two groups for control: the first group (forward / backward, lateral, yaw) that is controlled to satisfy the driver's requested operation amount, and the second group (up / down, pitch, roll) that is controlled to suppress vibration in order to improve the ride comfort of the vehicle 1.

[0053] The longitudinal target state quantities of the vehicle 1 are determined mainly by the driver's operation. It is predicted that the driver's operation will mainly consist of low-frequency components and will not include operations with high-frequency components above a certain level. For example, it is unlikely that the driver will frequently change the opening degree of the accelerator pedal 4, and similarly, it is unlikely that the driver will frequently operate the steering wheel 6A. On the other hand, the target values ​​for the vertical, pitch, and roll movements are not determined based on the driver's operation. Rather, emphasis is placed on suppressing vibrations of the vehicle 1 caused by disturbances to improve ride comfort, and it is predicted that the disturbances will include many high-frequency components. Therefore, in this embodiment, the longitudinal, lateral, and yaw movements, which are groups that are controlled to satisfy the driver's requested operation quantities, are controlled in the low-frequency range, while the vertical, pitch, and roll movements, which are groups that are controlled with target values ​​set to zero to improve the ride comfort of the vehicle 1, are controlled in the high-frequency range, thereby achieving both operability and ride comfort of the vehicle 1.

[0054] FIG. 11 is a functional block diagram of a control device 100B according to the third embodiment. The difference from the control device 100A according to the second embodiment is that a frequency extraction unit 160 is further provided. The frequency extraction unit 160 stores the operation history of the steering angle, accelerator, and brake by the driver together with time data as a "driver operation history." The frequency extraction unit 160 calculates the maximum frequency from the driver operation history and sets it as the cutoff frequency of the LPF 1411 and the HPF 1421. Note that the frequency extraction unit 160 only needs to calculate the maximum frequency from the driver operation history, and does not need to store the driver operation history for a long period of time.

[0055] In this embodiment, the total steering angle of the steering wheel 6A operated by the driver is also input to the control device 100B. Furthermore, in this embodiment, the longitudinal target state quantity calculation unit 101, the vertical target state quantity calculation unit 102, the longitudinal force calculation unit 104, and the vertical force calculation unit 105 are generalized into a first target state quantity calculation unit 171, a second target state quantity calculation unit 172, a first control request quantity calculation unit 175, and a second control request quantity calculation unit 176, respectively. The first target state quantity calculation unit 171 calculates a first target state quantity based on the accelerator position, the brake position, and the total steering angle. The first target state quantity is any one of longitudinal, lateral, and yaw accelerations. The second target state quantity calculation unit 172 calculates the second target state quantity, i.e., any one of vertical, pitch, and roll accelerations, as zero.

[0056] The first control demand quantity calculation unit 175 acquires the current value of the state quantity corresponding to the first target state quantity from the vehicle momentum sensor 120 and calculates the first control demand quantity. For example, if the first target state quantity is the acceleration in the longitudinal direction, the first control demand quantity calculation unit 175 acquires the current acceleration in the longitudinal direction from the vehicle momentum sensor 120 and calculates the first control demand quantity by subtracting the acquired value from the first target state quantity. The second control demand quantity calculation unit 176 acquires the current value of the state quantity corresponding to the second target state quantity from the vehicle momentum sensor 120 and calculates the second control demand quantity. The configuration of the combined control command quantity generation unit 140 is the same as that of the second embodiment. However, the cutoff frequencies of the LPF 1411 and the HPF 1421 are set by the frequency extraction unit 160.

[0057] The state quantities set as the first target state quantity and the second target state quantity are arbitrary, but when control is performed in an independent braking / driving one-wheel model as in the second embodiment, it is possible to perform control in the longitudinal direction and vertical direction of the vehicle 1, or control in the longitudinal direction and pitch of the vehicle 1. This makes it possible to achieve both operability, i.e., control in the longitudinal direction, and ride comfort, i.e., vertical or pitch control.

[0058] According to the above-described third embodiment, the following advantageous effects can be obtained. (7) The control device 100B includes a frequency extraction unit 160 that extracts the maximum frequency of the operation based on the operation history of the driver who operates the vehicle 1. The frequency characteristics are realized by a high-pass filter or a low-pass filter that uses the maximum frequency of the driver's operation as the cutoff frequency. The composite control command amount generation unit 140 applies a low-pass filter when the control axes are longitudinal, lateral, and yaw, and applies a high-pass filter when the control axes are vertical, pitch, and roll. This allows for both operability and ride comfort of the vehicle 1.

[0059] --Fourth embodiment-- A fourth embodiment of a control device and a control method will be described with reference to Figures 12 and 13. In the following description, the same components as those in the second embodiment are designated by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the second embodiment. This embodiment differs from the second embodiment mainly in that the number of control inputs is increased from one to two.

[0060] In this embodiment, there are two control inputs, and vehicle motion that can be achieved by braking / driving forces in five directions: forward / backward, yaw, up / down, pitch, and roll. This applies, for example, to a case where in-wheel motors are mounted on the left and right front or rear wheels and driven independently. In the fourth embodiment, as in the second embodiment, the vehicle motion components to be controlled are classified into a first group that is controlled in the low frequency range and a second group that is controlled in the high frequency range based on human vibration sensation. Then, by controlling in the frequency band corresponding to each group, vehicle motion components in a number greater than the number of control inputs can be controlled.

[0061] FIG. 12 is a schematic diagram showing frequency division in this embodiment. To clarify the features of this embodiment, a general control method is shown on the left side of the figure as a conventional control technique for comparison. In FIG. 12, the dashed rectangular slots stacked along the vertical axis correspond to the number of control inputs, in other words, the number of actuators. In the conventional technique, each actuator uses the entire frequency range to collectively control two vehicle motion components. For example, as shown on the left side of FIG. 12, it controls the yaw angle and the fore-and-aft motion. However, this does not mean that the first-stage control input controls only the fore-and-aft motion and the second-stage control input controls only the yaw motion. FIG. 12 merely schematically illustrates the relationship between the number of control inputs and the number of controllable vehicle motion components, and the frequency bands that control the vehicle motion components to be controlled.

[0062] In contrast, in this embodiment, each control input is divided into two at a predetermined frequency, for example, 3 Hz, and different vehicle motion components are controlled. That is, in this embodiment, four vehicle motion components are controlled in a 2x2 fashion. In conventional methods, the number of controllable vehicle motion components is determined according to the number of control inputs, i.e., the number of slots, and the vehicle motion component to be controlled could only be determined from among these. In the case of the left and right independent drive described above, only two of the five controllable vehicle motion components are selected and controlled. On the other hand, in this embodiment, the slots are divided along the x-axis (frequency axis) by specifying the frequency band to which control is applied for each vehicle motion component, thereby increasing the number of controllable vehicle motion components.

[0063] For example, as described in the third embodiment, the number of slots can be increased to four by dividing each slot into two at approximately 3 Hz, where human vibration sensations are reversed. Then, by allocating the vehicle motion components to be controlled to each of these four slots, it is determined which vehicle motion components are to be controlled in which frequency band. For example, in the case of independent drive of the left and right wheels, there are four slots for the five controllable vehicle motion components, namely, fore-aft, yaw, up-down, pitch, and roll. Therefore, there are five simple ways to allocate the vehicle motion components to each slot. However, in a division method based on human vibration sensation, it is important to suppress vibrations in the planar system in frequency bands lower than approximately 3 Hz, so it is necessary to allocate the fore-aft and yaw components. Furthermore, it is important to suppress vibrations in the vertical system in frequency bands higher than approximately 3 Hz, so it is necessary to allocate two of the three components, up-down, pitch, and roll, to the remaining two slots. Therefore, there are essentially three possible allocation methods.

[0064] In the case of a vehicle configuration that allows the left and right sides to be driven independently (for example, IWM, onboard motor, active differential; see Figure 3), there are five controllable components, so the area near the person is a low-frequency body and is a sensitive planar component, yaw, which can be added and controlled. However, even in this case, if a half-car model is used, it is not possible to create a difference in drive between the left and right sides.

[0065] FIG. 13 is a functional block diagram of a control device 100C according to the fourth embodiment. In this diagram, functional blocks for controlling control axes belonging to the first group are shown in the upper row, and functional blocks for controlling control axes belonging to the second group are shown in the lower row. The main differences between FIG. 13 and FIG. 11 of the third embodiment are that the number of combinations of target state quantity calculation units and control request calculation units is increased from two to four, and that the frequency extraction unit 160 is deleted. Furthermore, the calculation results of the first control request amount calculation unit 175 and the second control request amount calculation unit 176 are input to the one-side frequency processing unit 141, and the calculation results of the third control request amount calculation unit 177 and the fourth control request amount calculation unit 178 are input to the other-side frequency processing unit 142.

[0066] The accelerator position, brake position, and total steering angle are input to a first target state quantity calculation unit 171 and a second target state quantity calculation unit 172. As described above, the first target state quantity and the second target state quantity are target values ​​of the acceleration in the longitudinal direction and the angular velocity in the yaw direction. The first target state quantity calculation unit 171 and the second target state quantity calculation unit 172 calculate the first target state quantity and the second target state quantity based on the input accelerator position, brake position, and total steering angle. The third target state quantity calculation unit 173 calculates the third target state quantity, which is any one of the accelerations in the vertical direction, pitch direction, and roll direction, as zero, and outputs the calculated result to a third control request quantity calculation unit 177. The fourth target state quantity calculation unit 174 calculates the fourth target state quantity, which is any one of the accelerations in the vertical direction, pitch direction, and roll direction, as zero, and outputs the calculated result to a fourth control request quantity calculation unit 178. The vehicle motion quantity sensor 120 outputs current state quantities corresponding to the first control demand quantity calculation unit 175 to the fourth control demand quantity calculation unit 178, respectively.

[0067] The first braking / driving torque calculation unit 107 receives the target longitudinal force and the target yaw moment at the center of gravity of the vehicle as the target vehicle motion, and distributes them to the driving forces of the respective wheels. xfl , the driving force of the front right wheel F xfr Then, the longitudinal force generated at the center of gravity of the vehicle by these two driving forces is F xfl +F xrf On the other hand, the yaw moment M1 generated at the center of gravity of the vehicle by the driving force moves the front wheel tread to t f When the counterclockwise direction is defined as positive with respect to the yaw direction motion, it is expressed by the following Equation 2.

[0068] M1 = -t f x 0.5 x F xfl +t f x F xfr Formula 2

[0069] Therefore, the relationship between the driving force of each wheel and the center of gravity of the vehicle can be expressed by Equation 3.

[0070]

number

[0071] The first braking / driving torque calculation unit 107 calculates the driving force F xfl , F xfr In addition, F in Equation 3 x is the target longitudinal force, M z is the target yaw moment, so it is a constant in Equation 3, and F xfl , F xfr Since is an unknown quantity, it is possible to use an inverse matrix to perform the distribution. The torque command value for the motor is then calculated by multiplying the calculated driving force by the tire radius.

[0072] The second braking / driving torque calculation unit 108 receives control demands in the up / down direction and pitch direction, for example, as input, and calculates two-wheel driving force command values ​​that achieve the demands. In doing so, the second braking / driving torque calculation unit 108 calculates the driving force command values ​​based on Equation 4.

[0073]

number

[0074] The formula for calculating the driving force command value from the control request amount can be easily found by extracting the corresponding driving force and vehicle motion component elements from Equation 1. By applying LPF 1411 and HPF 1421 to the torque command value calculated above and then adding them up, control is performed in the low frequency range in the longitudinal direction and yaw direction, and in the high frequency range in the vertical direction and pitch direction.

[0075] According to the above-described fourth embodiment, the following advantageous effects can be obtained. (8) The vehicle 1 is equipped with two of the actuators, and realizes control of a first control axis, a second control axis, a third control axis, and a fourth control axis. These control axes are, for example, the yaw direction, the longitudinal direction, the pitch direction, and the roll direction. The specific frequency components prioritized for the first control axis and the second control axis are predetermined frequencies, for example, frequencies of 3 Hz or less. The specific frequency components prioritized for the third control axis and the fourth control axis are frequencies higher than the predetermined frequency. The control value synthesis unit 143 calculates a control command amount for the first actuator by synthesizing the control request amount for the first control axis and the control request amount for the third control axis. The control value synthesis unit 143 calculates a control command amount for the second actuator by synthesizing the control request amount for the second control axis and the control request amount for the fourth control axis.

[0076] (Modification 1 of the fourth embodiment) In the fourth embodiment described above, the number of control inputs was two, and vehicle motion could be achieved in five directions by braking / driving forces. However, as will be explained below, the present invention can be applied to a case where the number of control inputs is two and vehicle motion could be achieved in three directions, i.e., forward / backward, up / down, and pitch. This corresponds, for example, to a case where the left and right front wheels are driven simultaneously, and the left and right rear wheels are driven simultaneously and independently of the front wheels.

[0077] FIG. 14 is a diagram showing the relationship between control components and corresponding frequency bands in Modification 1 of the fourth embodiment. There are two control inputs, and by dividing the frequency band into two, up to four components can be controlled, but there are only three vehicle motion components to be controlled. Therefore, the following two patterns are possible. The first pattern is a pattern in which the longitudinal movement and pitch are controlled in low frequency ranges, and the vertical movement and pitch are controlled in high frequency ranges. The second pattern is a pattern in which the longitudinal movement and vertical movement are controlled in low frequency ranges, and the pitch and vertical movement are controlled in high frequency ranges. In the first pattern, pitch is controlled over the entire frequency range, and in the second pattern, vertical movement is controlled over the entire frequency range. The choice of which pattern to use is left to the discretion of the user of the control device 100C, etc.

[0078] FIG. 15 is a functional block diagram of a control device 100C in a first modified example of the fourth embodiment. The difference from FIG. 13 is that there are three sets of target state quantity calculation units and control demand quantity calculation units, one less set. The second control demand quantity calculation unit 176 outputs its calculation results to both the first braking / driving torque calculation unit 107 and the second braking / driving torque calculation unit 108, with the LPF 1411 applied to the former and the HPF 1421 applied to the latter. That is, the output of the second control demand quantity calculation unit 176 is used for control over the entire frequency range. When the first pattern is selected from the two patterns described above, the first target state quantity is longitudinal, the second target state quantity is pitch, and the third target state quantity is vertical. When the second pattern is selected, the first and second patterns are swapped, with the first target state quantity being pitch, the second target state quantity being longitudinal, and the third target state quantity being vertical.

[0079] (Modification 2 of the fourth embodiment) When the left and right rear wheels are independently driven and the front wheels are steered, control may be performed in a manner generally similar to that of variant 1 of the fourth embodiment described above. However, it is preferable to omit the low-pass filter in consideration of the delayed response to the generation of lateral force associated with front wheel steering, as described below.

[0080] Figure 16 is a schematic diagram showing the difference in response between braking / driving force and lateral force. It is generally known that the response of lateral force generated by steering, i.e., by angled wheels, is slower than that of braking / driving force generated by a motor, i.e., the force in the longitudinal direction of vehicle 1. Specifically, it is known that the relationship between motor torque and driving force can be approximated by a constant multiple, while the relationship between steering angle and lateral force can be approximated by a first-order lag. Note that this constant multiple is the value obtained by dividing the driving force by the tire radius. As shown on the left side of Figure 16, when the target value of braking / driving force is changed at time t1, the target value is reached in an extremely short time. This shows that the braking / driving force can also track high-frequency target values.

[0081] On the other hand, the relationship between steering angle and lateral force, which is approximated by a first-order delay, changes lateral force gradually when steering is changed at time t2, as shown on the right side of Fig. 16. This first-order delay has the same characteristics as the LPF 1411, and the gain decreases in the high-frequency band above a certain frequency. Therefore, it is expected that lateral force can only be generated in the low-frequency band, making it difficult to control vehicle motion components in the high-frequency band by steering.

[0082] Figure 17 is a schematic diagram showing a division method that takes into account the difficulty of controlling vehicle motion components in the high frequency band by steering. There are three control inputs: left rear wheel, right rear wheel, and front wheel steering, so there are three slots. However, as mentioned above, with front wheel steering, vehicle motion components can only be controlled in the low frequency band, so one slot cannot use the high frequency band slot. Therefore, three combinations are possible, as shown in Figure 16.

[0083] FIG. 18 is a functional block diagram of a control device 100C in a second modification of the fourth embodiment. The number of control inputs is three, and since they are divided by a predetermined frequency, for example, 3 Hz, six components can be simply controlled (3 x 2). However, as mentioned above, front wheel steering is only in the low frequency band, so there are five control targets. As shown in FIG. 18, this functional block diagram has five sets of target state quantity calculation units and control request quantity calculation units. The first to third target state quantities are longitudinal, lateral, and yaw. Originally, these three quantities are in any order and can be interchanged, but the order is fixed to omit the LPF 1411 described later.

[0084] One-side frequency processing unit 141 calculates the rear right wheel driving force, rear left wheel driving force, and front wheel steering angle required to realize the longitudinal, lateral, and yaw movements of vehicle 1, and then applies LPF 1411. However, since the steering angle has a first-order lag with respect to the lateral force generated in the tires due to steering, i.e., a relationship with LPF 1411, the lateral force due to steering does not affect the high frequency band even if one-side frequency processing unit 141 does not explicitly apply LPF 1411. Therefore, the third LPF from the top, which corresponds to third control requirement calculation unit 177, can be omitted. On the other hand, the other-side frequency processing unit 142 calculates the rear right wheel driving force and rear left wheel driving force required to realize the target pitch and vertical movement of vehicle 1, and then applies HPF 1421. Finally, the two command values ​​are summed to obtain the final command value.

[0085] --Fifth embodiment-- A fifth embodiment of a control device and a control method will be described with reference to Figures 19 and 20. In the following description, the same components as in the first embodiment are designated by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as in the first embodiment. This embodiment differs from the first embodiment mainly in that the number of control inputs is four and there are five possible vehicle motions. In this embodiment, there are four control inputs, and the vehicle motions that can be realized by braking / driving forces are five directions: forward / backward, yaw, up / down, pitch, and roll. This corresponds to, for example, a case where in-wheel motors are installed on all four wheels and the four wheels are braked and driven independently.

[0086] Fig. 19 is a diagram showing the relationship between control components and corresponding frequency bands in the fifth embodiment. In this embodiment, four actuators are provided, so the number of control inputs is four and the frequency band is divided into two, so up to eight components can be controlled. In contrast, there are five vehicle motion components to be controlled, so three components have a margin and can be controlled across the entire frequency range. Therefore, six combinations are possible, as shown in Fig. 19.

[0087] FIG. 20 is a functional block diagram of a control device 100D according to the fifth embodiment. Similar to FIG. 18, this functional block diagram includes five sets of target state quantity calculation units and control request quantity calculation units. The first control request quantity calculation unit 175 outputs only to the one-side frequency processing unit 141, and the fifth control request quantity calculation unit 180 outputs only to the other-side frequency processing unit 142. The second control request quantity calculation unit 176 to the fourth control request quantity calculation unit 178 output to the one-side frequency processing unit 141 and the other-side frequency processing unit 142 to perform control over the entire frequency range. For example, when the upper left combination shown in FIG. 19 is used, the first target state quantity is longitudinal, the fifth target state quantity is vertical, and the second to fourth target state quantities are yaw, roll, and pitch, in any order.

[0088] According to the above-described fifth embodiment, the following advantageous effects can be obtained. (9) When the number of actuators is N (N is an integer greater than or equal to 1), the number of control axes is M, and 2N>M is satisfied, the composite control command generator 140 prioritizes the full frequency range for 2N-M of the control axes, prioritizes the low frequency range for MN of the control axes excluding the 2N-M, and prioritizes the high frequency range for the remaining MN control axes. Specifically, since the number of actuators, N, is 4, and the number of control axes, M, is 5, the condition 2*4>5 is satisfied. In this case, the three 2N-M control axes, such as yaw, roll, and pitch, prioritize the full frequency range, the one MN control axis, such as forward / backward, prioritizes the low frequency range, and the remaining MN control axes, such as up / down, prioritize the high frequency range.

[0089] -Sixth embodiment- A sixth embodiment of a control device and a control method will be described with reference to Figures 21 and 22. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the first embodiment. This embodiment differs from the first embodiment in that the frequency is divided into three or more parts.

[0090] FIG. 21 is a diagram showing the relationship between control components and corresponding frequency bands in the sixth embodiment. In this example, there is one control input, and the control frequency is divided into five to control five vehicle components. In this case, the frequencies that separate the frequency bands are called f1 to f4. Here, the frequencies are, in order from the lowest to the highest, longitudinal, yaw, vertical, roll, and pitch. As a criterion for dividing the frequency bands to be controlled, it is conceivable to extract and control frequency bands near the resonance points of each vehicle motion.

[0091] FIG. 22 is a functional block diagram of a control device 100E according to the sixth embodiment. The configuration will be described here in association with FIG. 21. This functional block diagram includes five sets of target state quantity calculation units and control request quantity calculation units. The first to fifth target state quantities are longitudinal, yaw, vertical, roll, and pitch, respectively. The combined control command quantity generation unit 140 includes a braking / driving torque calculation unit 144, an LPF 1411, a first BPF 1431, a second BPF 1432, a third BPF 1433, an HPF 1421, and a control value combination unit 143.

[0092] The LPF 1411 extracts frequency components of frequency f1 Hz or less from a torque command value for vehicle motion in the longitudinal direction. The first BPF 1431 is a band-pass filter and extracts frequency components of frequency f1 Hz to f2 Hz from a torque command value for vehicle motion in the yaw direction. The second BPF 1432 is a band-pass filter and extracts frequency components of frequency f2 Hz to f3 Hz from a torque command value for vehicle motion in the vertical direction. The third BPF 1433 is a band-pass filter and extracts frequency components of frequency f3 Hz to f4 Hz from a torque command value for vehicle motion in the roll direction. The HPF 1421 extracts frequency components of frequency f4 Hz or more from a torque command value for vehicle motion in the pitch direction. However, the correspondence between the first BPF 1431 to the third BPF 1433 and yaw, vertical, and roll is in no particular order and may be interchanged as desired.

[0093] According to the sixth embodiment described above, the following advantages can be obtained: Even when there is only one actuator, three or more control axes can be controlled by dividing the frequency into multiple parts.

[0094] --Seventh embodiment-- A seventh embodiment of a control device and a control method will be described with reference to FIG. 23. In the following description, the same components as those in the fourth embodiment will be assigned the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the fourth embodiment. This embodiment differs from the fourth embodiment in that the frequency division is dynamically changed. However, the description here is based on the fourth embodiment as an example, and may be combined with any other embodiment or modification.

[0095] 23 is a functional block diagram of a control device 100F according to the seventh embodiment. The control device 100F further includes a crisis response unit 185 in addition to the configuration of the control device 100C according to the fourth embodiment. The crisis response unit 185 detects a dangerous event and changes the configuration of the control device 100F. The change in configuration is directed to the control axes targeted by the first target state quantity calculation unit 171 to the third target state quantity calculation unit 173, and also changes the accelerator position, brake position, and total steering angle to be input to the second target state quantity calculation unit 172 and the third target state quantity calculation unit 173 as necessary, and changes the connections between the functional blocks.

[0096] The emergency response unit 185 detects an impending danger for the vehicle 1 using captured images captured by a camera (not shown) equipped in the vehicle 1, the output of an acceleration sensor (not shown) equipped in the vehicle 1, the amount of steering angle operation by the driver, and the like. For example, when using captured images, the emergency response unit 185 detects a moving object such as an automobile from the captured images, tracks it over time, and determines that a dangerous event has occurred if there is a high possibility of the moving object colliding with the vehicle 1. When the emergency response unit 185 detects the occurrence of a dangerous event, it does not control vertical vehicle motion components (up / down, pitch, roll) related to ride comfort, but controls horizontal motion components (forward / backward, lateral, yaw) across all frequency ranges. For example, the outputs of the emergency response unit 185, the first control demand amount calculation unit 175, and the second control demand amount calculation unit 176 are input not only to the one-side frequency processing unit 141 but also to the other-side frequency processing unit 142, thereby validating the horizontal motion components across all frequency ranges. This processing enables the emergency response unit 185 to improve the safety of the vehicle 1.

[0097] --Eighth embodiment-- An eighth embodiment of a control device and a control method will be described with reference to Fig. 24. In the following description, the same components as those in the second embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the second embodiment. In this embodiment, the order of torque calculation and filter application is different from that of the second embodiment.

[0098] FIG. 24 is a functional block diagram of a control device 100G in the eighth embodiment. The difference from FIG. 6 in the second embodiment is that the order of the first braking / driving torque calculation unit 107 and the LPF 1411 is swapped, and the order of the second braking / driving torque calculation unit 108 and the HPF 1421 is swapped. Swapping these orders does not affect the calculation results. Specifically, the LPF 1411 and the HPF 1421 are applied to the target signals calculated by the longitudinal force calculation unit 104 and the vertical force calculation unit 105, and then the driving torque corresponding to the target signal to which the frequency characteristic has been applied is calculated. The calculated driving torque is the control request amount itself, and is combined in the control value combination unit 143.

[0099] According to the above-described eighth embodiment, the following advantageous effects can be obtained. (10) One-side frequency processing section 141 and other-side frequency processing section 142, which can also be called control demand amount calculation sections, calculate the control demand amount by applying a frequency characteristic predetermined for each control axis to the target signal and then calculating the corresponding drive torque. Therefore, even if the calculation procedure is different from that of the second embodiment, the same effects as those of the second embodiment can be obtained.

[0100] In none of the above-described embodiments and modifications does the hardware configuration of the control device 100 be illustrated. However, the control device 100 may be realized by the following hardware configuration.

[0101] FIG. 25 is a diagram showing the hardware configuration of the control device 100. However, the control devices 100A to 100E may also be realized by a similar hardware configuration. The control device 100 includes a CPU 41, which is a central processing unit, a ROM 42, which is a read-only storage device, a RAM 43, which is a readable and writable storage device, and a communication device 45. The CPU 41 loads a program stored in the ROM 42 into the RAM 43 and executes it, thereby performing the various calculations described above. For example, the target signal calculation unit 101-0 and the composite control command amount generation unit 140-0 shown in FIG. 4 are also realized by the CPU 41, the ROM 42, and the RAM 43.

[0102] The control device 100 may be realized by a field programmable gate array (FPGA), which is a rewritable logic circuit, or an application specific integrated circuit (ASIC), which is an integrated circuit for a specific application, instead of the combination of the CPU 41, the ROM 42, and the RAM 43. Furthermore, the control device 100 may be realized by a combination of different configurations, for example, a combination of the CPU 41, the ROM 42, the RAM 43, and the FPGA, instead of the combination of the CPU 41, the ROM 42, and the RAM 43.

[0103] The communication device 45 is a communication module that enables the control device 100 to communicate with other devices mounted on the vehicle 1. The communication that the communication device 45 achieves may be wireless communication or wired communication. When the communication device 45 achieves wired communication, the communication device 45 may have an AD converter or a DA converter built in and achieve analog communication with the outside of the control device 100, for example, communication at 4-20 mA or 1-5 V. Also, for the sake of convenience, FIG. 24 illustrates the control device 100 as being composed of one hardware device, but the control device 100 may be composed of multiple hardware devices.

[0104] In each of the above-described embodiments and modifications, the functional block configurations are merely examples. Some functional configurations shown as separate functional blocks may be configured as an integrated unit, or a configuration shown in a single functional block diagram may be divided into two or more functions. Furthermore, some of the functions of each functional block may be provided by other functional blocks.

[0105] In the above-described embodiments and modifications, the program is stored in ROM 42, but the program may be stored in a non-volatile memory (not shown). Furthermore, the control device 100 may be provided with an input / output interface (not shown), and the program may be loaded from another device as needed via the input / output interface and a medium available to the control device 100. Here, the medium refers to, for example, a storage medium detachable from the input / output interface, or a communication medium, i.e., a wired, wireless, or optical network, or a carrier wave or digital signal propagating through the network. Furthermore, some or all of the functions realized by the program may be realized by a hardware circuit or FPGA.

[0106] The above-described embodiments and modifications may be combined with each other. For example, in the fourth and fifth embodiments, the frequency band to be controlled may be divided based on the highest frequency of the driver's operation from the driver operation history, as in the second embodiment. Although various embodiments and modifications have been described above, the present invention is not limited to these. Other aspects conceivable within the scope of the technical concept of the present invention are also included within the scope of the present invention. [Explanation of symbols]

[0107] 1: Vehicle 7: In-wheel motor 100, 100A to 100G: Control device 107: First braking / driving torque calculation unit 108: Second braking / driving torque calculation unit 109: Third braking / driving torque calculation unit 110: First filter 112: Second filter 113: Third filter 140, 140-0: Composite control command amount generation unit 141: One-side frequency processing section 142: Other side frequency processing section 143: Control value synthesis unit 144: Braking / driving torque calculation unit 149: Control demand amount calculation unit 160: Frequency extraction unit 171: First target state quantity calculation unit 172: Second target state quantity calculation unit 173: Third target state quantity calculation unit 175: First control demand amount calculation unit 176: Second control demand amount calculation unit 177: Third control demand calculation unit

Claims

1. A control device that is mounted on a vehicle having one or more independently controllable actuators and that realizes control of a plurality of control axes that is greater than the number of the actuators, comprising: a composite control command amount generating unit for generating a control command amount for each of the actuators by combining a plurality of control request amounts, which are control amounts required for each of the control axes; The control device, wherein the composite control command amount generator prioritizes a specific frequency component for each of the control axes.

2. The control device according to claim 1, a calculation unit that calculates a target signal that is a time-series target value for each of the control axes, The composite control command amount generator a control demand amount calculation unit that calculates, for each control axis, a drive torque of the actuator in a time series in which the specific frequency component is prioritized, as the control demand amount, based on the target signal and frequency characteristics predetermined for each control axis; a synthesis unit that synthesizes the control request amounts for the respective control axes for the corresponding actuators to generate the control command amounts, A control device, wherein the control request amounts corresponding to the same actuator each have a different specific frequency component that is given priority.

3. The control device according to claim 2, the vehicle includes two of the actuators, and controls a first control axis, a second control axis, a third control axis, and a fourth control axis are realized; the specific frequency component prioritized for the first control axis and the second control axis is a frequency equal to or lower than a predetermined frequency, the specific frequency component prioritized for the third control axis and the fourth control axis is a frequency greater than the predetermined frequency, The synthesis unit calculating a control command amount for the first actuator by combining the control demand amount for the first control axis and the control demand amount for the third control axis; a control device that calculates a control command amount for the second actuator by combining the control demand amount for the second control axis and the control demand amount for the fourth control axis.

4. The control device according to claim 2, The control device wherein the control demand amount calculation unit calculates a drive torque corresponding to the target signal, and calculates the control demand amount by applying a frequency characteristic predetermined for each of the control axes to the drive torque.

5. The control device according to claim 2, The control device, wherein the control demand calculation unit calculates the control demand by applying a frequency characteristic predetermined for each of the control axes to the target signal and then calculating a corresponding drive torque.

6. The control device according to claim 2, The control device, wherein the control request amount calculation unit applies the frequency characteristics using any one of a low-pass filter, a high-pass filter, a band-pass filter, and a band-stop filter.

7. The control device according to claim 2, When the number of the actuators is N (N is an integer of 1 or more), the number of the control axes is M, and 2N>M is satisfied, The composite control command amount generator 2N-M of the control axes prioritize the entire frequency range, M-N of the control axes excluding the 2N-M axes prioritize a low frequency range, The remaining M-N control axes prioritize the high frequency range.

8. The control device according to claim 2, the frequency characteristics are realized by a high-pass filter and a low-pass filter in which threshold frequencies based on human perception are set; The composite control command amount generator When the control axes are longitudinal and yaw, a low-pass filter is applied; A control device that applies a high pass filter when the controlled axes are up / down, pitch, and roll.

9. The control device according to claim 2, a frequency extraction unit that extracts a maximum frequency in an operation based on an operation history of a driver who operates the vehicle; the frequency characteristics are realized by a high-pass filter or a low-pass filter having the maximum frequency as a cutoff frequency, The composite control command amount generator applying a low pass filter when the control axes are fore-aft, lateral, and yaw; A control device that applies a high-pass filter when the control axis is up / down, pitch, or roll.

10. The control device according to claim 1, The control device, wherein the actuator is an in-wheel motor provided on a wheel that constitutes the vehicle.

11. A control method executed by a control device that includes one or more independently controllable actuators and controls a plurality of control axes, the number of which is greater than the number of the actuators, comprising: a composite control command amount generating step of generating, for each of the actuators, a control command amount for the actuator by combining the plurality of control request amounts; In the synthetic control command amount generating step, a specific frequency component is given priority for each of the control axes.

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