JP2014012447A - Vehicle body damping control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure suppression of vehicle body vibration caused by a disturbance input even when a position of wheel center is varied from a designed position in a disturbance input traveling scene where a suspension is displaced.SOLUTION: A vehicle body damping control apparatus comprises an input conversion unit 204, a vehicle body vibration estimation unit 205, and a torque command value calculation unit 206. The input conversion unit 204 of the vehicle body damping control apparatus includes a suspension stroke calculation unit 302 and a vertical force conversion unit 303 which estimate a disturbance input on the basis of wheel speed fluctuation using a tire displacement nonlinear map mapping a relation characteristic between a force-and-aft direction displacement and a vertical direction displacement with respect to a position of wheel center on the basis of a suspension geometry. A nonlinear map correction processing unit 321 is provided to correct, when the position of wheel center is varied from the designed position in a static state on a flat road, tire displacement nonlinear maps F(MapF) and F(MapR) in a direction to suppress a deviation of the position of wheel center.

Description

  The present invention relates to a vehicle system vibration control device that suppresses an estimated sprung behavior of a vehicle body during driving by correction control of driving torque.

  2. Description of the Related Art Conventionally, a driving force control device for a vehicle is known in which driving torque and wheel speed are input, vehicle vibration is estimated from these differential values, and driving torque is controlled to suppress vehicle vibration (for example, Patent Document 1).

JP 2009-247157 A

  However, in the conventional driving force control device, although the vehicle body vibration due to the torque fluctuation input is included in the vibration suppression control object, the sprung behavior due to the disturbance is not included in the control object. There was a problem that the effect of suppressing vehicle body vibration could not be expected.

  The present invention has been made paying attention to the above problem, and in a disturbance input traveling scene in which the suspension is displaced, even when the wheel center position is changed from the design position, a vehicle system that ensures suppression of vehicle body vibration due to disturbance input. An object is to provide a vibration control device.

In order to achieve the above-mentioned object, the vehicle system vibration control device of the present invention includes a front-rear direction of a wheel center position based on a suspension geometry in an input conversion unit that converts sensing information from a vehicle acquired during traveling into wheel input. A disturbance input estimation unit is provided that estimates a disturbance input based on wheel speed fluctuations using a tire displacement nonlinear map in which a relationship characteristic of a vertical displacement with respect to a displacement is mapped.
The disturbance input estimation unit is provided with a non-linear map correction processing unit that corrects the tire displacement non-linear map in a direction to suppress the wheel center position deviation when the wheel center position in a flat road stationary state changes from the design position. It was.
Here, the “suspension geometry” means a geometric shape such as an arm length and an attachment position designed to determine a movement of a suspension that supports each wheel of the vehicle on the vehicle body, and a relative position.

The disturbance input is estimated using a tire displacement nonlinear map determined by the design value of the wheel center position in a flat road stationary state. On the other hand, if there are assembly errors in the production line or changes over time due to continuous use for many years, the wheel center position changes from the design position. Therefore, even if the wheel center position is changed from the design position, if the tire displacement nonlinear map determined by the design position standard is used as it is, the estimation accuracy of the disturbance input is lowered.
On the other hand, when the wheel center position in the flat road stationary state is changed from the design position, the nonlinear map correction processing unit corrects the tire displacement nonlinear map in a direction to suppress the wheel center position deviation. Therefore, when the wheel center position changes from the design position due to an assembly error or a secular change, the disturbance input estimation unit using the tire displacement nonlinear map ensures the estimation accuracy of the disturbance input based on the wheel speed fluctuation.
As described above, when the wheel center position is changed from the design position, the wheel center position is adjusted in a disturbance input traveling scene in which the suspension is displaced by correcting the tire displacement nonlinear map in a direction to suppress the wheel center position deviation. Even if the position is changed from the design position, it is possible to ensure suppression of vehicle body vibration due to disturbance input.

1 is an overall system configuration diagram showing an engine vehicle to which a vehicle system vibration control device of Embodiment 1 is applied. It is a control block diagram which shows the control program structure in the engine control module in the engine vehicle system of Example 1. FIG. It is a control block diagram which shows the vehicle system vibration control apparatus in the engine control module of Example 1. FIG. 6 is a schematic diagram showing that the tire is displaced in the front-rear direction when the suspension strokes in the description of the suspension stroke calculation unit of the first embodiment. It is a front-wheel tire displacement nonlinear characteristic figure which shows an example of the relationship characteristic of the front-back and up-down direction displacement of the wheel center position based on the suspension geometry in the suspension stroke calculation part which has in the input conversion part of Example 1. FIG. It is a rear-wheel tire displacement nonlinear characteristic figure which shows an example of the relationship characteristic of the front-back and up-down direction displacement of the wheel center position based on the suspension geometry in the suspension stroke calculation part which has in the input conversion part of Example 1. FIG. It is a vehicle model figure which shows what represented the vehicle model which has in the vehicle body vibration estimation part of Example 1 graphically. It is a block diagram which shows the structure of the 1st-3rd regulator part which has in the torque command value calculation part of Example 1, the 1st-3rd tuning gain setting part, and an adder. It is a gain function explanatory drawing which shows the function which each regulator gain set to the 1st-3rd regulator part which has in the torque command value calculation part of Example 1 exhibits. 3 is a block diagram illustrating a detailed configuration of a high-pass filter, a suspension stroke calculation unit, a vertical force conversion unit, and a nonlinear map correction processing unit that are included in the input conversion unit of Embodiment 1. FIG. It is a flowchart which shows the gradient determination process structure (a) in the gradient determination part of the nonlinear map correction process part of Example 1, and the steady state determination process structure (b) in a steady state determination part. 6 is a flowchart illustrating a gradient-corresponding nonlinear map correction processing configuration in a nonlinear map correction unit of the nonlinear map correction processing unit according to the first embodiment. 3 is a flowchart illustrating a non-linear map correction processing configuration corresponding to a wheel center position change in a non-linear map correction unit of the non-linear map correction processing unit of the first embodiment. Front wheel tire displacement non-linear map on flat road (a), front wheel tire displacement non-linear map on down slope road (b), front wheel tire displacement non-linear map on up slope road (c) used in the non-linear map correction processing of Embodiment 1 It is a figure which shows an example. Rear wheel tire displacement non-linear map on flat road (a), rear wheel tire displacement non-linear map on uphill road (b), rear wheel tire displacement non-linear map on downhill road used in the non-linear map correction processing of Embodiment 1 It is a figure which shows an example of (c). It is a flowchart which shows the flow of the vehicle structure vibration control process performed in the engine control module of Example 1. FIG. It is explanatory drawing of the basic effect | action of vehicle structure vibration control, and shows the driving condition (a), the time chart (b) of an axle torque characteristic, and the time chart (c) of a pitch angular velocity characteristic. It is a principle explanatory view showing basic principles of “improvement of steering response”, “suppression of load fluctuation”, and “suppression of roll speed”, which are the effects aimed at the vehicle system vibration control of the first embodiment. It is a logic block diagram which shows the logic detail of the vehicle structure vibration control of Example 1. FIG. Pitch rate (no control), steering input, control command value (= drive torque command value), pitch rate (after control) representing the effect realized during steering in a vehicle equipped with the vehicle system vibration control device of the first embodiment. It is a time chart which shows the contrast characteristic of a yaw rate (after control) and a roll rate (after control). It is an operation explanatory view showing that a change to the vehicle height (suspension geometry) in a flat road stationary state occurs due to an assembly error or a secular change. It is an operation explanatory view showing that a balance position changes in a design value state at the initial stage of production and a vehicle state after being put on the market in the rear wheel tire displacement characteristics in a flat road stationary state. It is an operation explanatory view showing how the rear wheel tire displacement characteristic changes from the rear wheel tire displacement characteristic in the design value state in the initial stage of production when the balance position is corrected in the vehicle state after being put on the market. It is explanatory drawing which shows the map axis | shaft base point correction | amendment method of the rear-wheel tire displacement nonlinear map by the suspension vertical displacement difference which the nonlinear map correction | amendment part of the nonlinear map correction | amendment process part of Example 1 has. It is a figure which shows the selection table of the front-wheel tire displacement nonlinear map and the rear-wheel tire displacement nonlinear map which show the other Example which divided the tire displacement nonlinear map correction process in steps.

  Hereinafter, the best mode for realizing a vehicle system vibration control device of the present invention will be described based on Example 1 shown in the drawings.

First, the configuration will be described.
The configuration in the first embodiment is defined as [overall system configuration], [internal configuration of engine control module], [input conversion unit configuration of vehicle system vibration control device], [vehicle body vibration estimation unit configuration of vehicle system vibration control device], [ The torque command value calculation unit configuration of the vehicle system vibration control device] and the [tire displacement nonlinear map correction processing configuration] will be described separately.

[Overall system configuration]
FIG. 1 is an overall system configuration diagram illustrating an engine vehicle to which the vehicle system vibration control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.
Here, “vehicle system vibration control” has a function of suppressing vehicle body vibration by appropriately controlling the drive torque by the vehicle actuator (“engine 106” in the first embodiment) in accordance with the vibration of the vehicle body. Refers to control. In the vehicle system vibration control of the first embodiment, the effect of improving the yaw response at the time of steering, the effect of improving the linearity at the time of steering, and the effect of suppressing the roll behavior are also obtained.

  As shown in FIG. 1, the engine vehicle to which the vehicle system vibration control device of the first embodiment is applied is a rear wheel drive vehicle by manual shift, and includes an engine control module (ECM) 101 and an engine 106. Yes.

  The engine control module 101 (hereinafter referred to as “ECM101”) performs drive torque control of the engine 106. This ECM101 is connected to the steering wheel 110 and signals from wheel speed sensors 103FR, 103FL, 103RR, 103RL connected to the left and right front wheels 102FR, 102FL (driven wheel) and the left and right rear wheels 102RR, 102RL (drive wheel). A signal from the steering angle sensor 111 is input. Further, a signal from the brake stroke sensor 104 that detects the driver operation amount to the brake pedal and a signal from the accelerator opening sensor 105 that detects the driver operation amount to the accelerator pedal are input. A torque command value for driving the engine 106 is calculated according to these input signals, and the torque command value is sent to the engine 106.

  The engine 106 generates a drive torque according to the torque command value from the ECM 101, and the generated drive torque is increased / decreased by the MT transmission 107 according to the shift operation of the driver. The drive torque changed by the MT transmission 107 is further changed by the shaft 108 and the differential gear 109 and transmitted to the left and right rear wheels 102RR and 102RL to drive the vehicle.

[Internal configuration of engine control module]
The vehicle structure vibration control device is configured in the form of a control program in the ECM 101, and FIG. 2 shows a block configuration representing the control program in the ECM 101. Hereinafter, the internal configuration of the ECM 101 will be described with reference to FIG.

  As shown in FIG. 2, the ECM 1101 includes a driver request torque calculation unit 201, a torque command value calculation unit 202, and a vehicle system vibration control device 203.

  The driver request torque calculation unit 201 inputs the brake operation amount information by the driver from the brake stroke sensor 104 and the accelerator operation amount information by the driver from the accelerator opening sensor 105, and calculates the driver request torque.

  The torque command value calculation unit 202 includes a torque command value obtained by adding the correction torque value from the vehicle system vibration control device 203 to the driver request torque from the driver request torque calculation unit 201, and other in-vehicle systems (for example, VDC and TCS). Etc.) is input. Based on the input information, a drive torque command value for the engine 106 is calculated.

  The vehicle system vibration control device 203 has a three-part configuration including an input conversion unit 204, a vehicle body vibration estimation unit 205, and a torque command value calculation unit 206. The input conversion unit 204 converts sensing information from the vehicle acquired during traveling into wheel input. The vehicle body vibration estimation unit 205 estimates the sprung behavior of the vehicle body using each wheel input from the input conversion unit 204 and the vehicle model. The torque command value calculation unit 206 suppresses the sprung behavior of the vehicle body based on the sprung behavior state quantity (bounce speed, bounce amount, pitch speed, pitch angle) of the vehicle body estimated by the vehicle body vibration estimation unit 205. The correction torque value is calculated.

[Configuration of input converter of vehicle system control device]
Based on FIGS. 3-6, the structure of the input conversion part 204 is demonstrated among the vehicle structure vibration control apparatuses 203 of 3 parts structure.

  The input conversion unit 204 converts sensing information from the vehicle into an input format (specifically, a dimension of torque or force applied to the wheels) to the vehicle model 307 used in the subsequent vehicle body vibration estimation unit 205. As shown in FIG. 3, the input conversion unit 204 includes a drive torque conversion unit 301, a high-pass filter 316, a suspension stroke calculation unit 302, a vertical force conversion unit 303, a vehicle body speed estimation unit 304, and a turning behavior estimation. A unit 305, a turning resistance calculation unit 306, and a nonlinear map correction processing unit 321. In the input conversion unit 204, as input to the vehicle body vibration estimation unit 205, the drive shaft end torque Tw, the front wheel vertical force Ff and the rear wheel vertical force Fr, the front wheel turning resistance force Fcf, and the rear wheel turning resistance force Fcr , Is calculated.

<Calculation configuration of drive shaft end torque Tw>
The drive torque converter 301 adds the gear ratio to the driver request torque from the driver request torque calculator 201 and converts the engine end torque to the drive shaft end torque Tw. Here, the gear ratio is calculated from the ratio of the wheel speed (the average left and right rotational speed of the drive wheel) and the engine rotational speed. This gear ratio is the total gear ratio of the MT transmission 107 and the differential gear 109.

<Configuration for calculating front and rear wheel vertical forces Ff and Fr>
The high-pass filter 316 removes low-order steady components from the wheel speed signals from the wheel speed sensors 103FR, 103FL, 103RR, and 103RL. As the high-pass filter 316, a low-order filter having high stability and low calculation load is used.

The suspension stroke calculation unit 302 calculates the suspension stroke speed and the suspension stroke amount based on the wheel speed information after the high-pass filter process. When the suspension strokes, as shown in FIG. 4, the tire also has a displacement in the front-rear direction, and this relationship is determined by the suspension geometry of the vehicle. This is illustrated in FIGS. 5 and 6, which show nonlinear characteristics with respect to the displacement in the vertical and longitudinal directions of the tire, and this relationship is directly mapped by an approximate expression or the like as a tire displacement nonlinear map f (MapF), Prepare f (MapR). The tire displacement nonlinear maps f (MapF) and f (MapR), the front and rear positions xtf and xtr of the tire, and the vertical displacements Zf and Zr of the front and rear wheels have the following relationship.
Zf = F (MapF) xtf (1)
Zr = F (MapR) xtr (2)
Here, the front and rear positions xtf and xtr of the tire are estimated from wheel speed differential values representing wheel speed fluctuations. For example, when traveling on an uneven road, which is a road surface disturbance, when the tire rides on a convex portion, the wheel speed is reduced and the tire is displaced in the vehicle rearward direction with respect to the vehicle body. On the other hand, when the tire gets over the convex portion, the wheel speed is accelerated, and the tire is displaced in the vehicle front direction with respect to the vehicle body. Therefore, if the acceleration / deceleration of the tire is determined based on whether the wheel speed differential value is positive or negative, the front and rear positions xtf and xtr of the tire can be estimated based on the absolute value of the wheel speed differential value.
Therefore, once the tire displacement nonlinear maps F (MapF), F (MapR) and the front / rear positions xtf, xtr of the tire are determined, the vertical displacements Zf, Zr of the front / rear wheels are calculated by the above formulas (1), (2). Is required.
When the above equations (1) and (2) are differentiated with respect to time, the tire longitudinal speed and the tire vertical speed are obtained, and the suspension stroke speed and the suspension stroke amount are calculated using this relationship.

  In the vertical force conversion unit 303, the spring coefficient and the damping coefficient are added to the suspension stroke speed and the suspension stroke amount calculated by the suspension stroke calculation unit 302, respectively, and the sum is taken to obtain the front wheel vertical force Ff and the rear wheel. Convert to vertical force Fr.

  The non-linear map correction processing unit 321 uses the tire displacement non-linear maps F (MapF) and F (MapR) of the front and rear wheels based on the suspension geometry used in the suspension stroke calculation unit 302, the estimated gradient value and the design position of the wheel center position. Correction processing is performed according to the change from. Detailed configuration will be described later.

<Calculation configuration of front and rear wheel turning resistance forces Fcf and Fcr>
The vehicle body speed estimation unit 304 outputs the wheel speed average value of the driven wheels 102FR and 102FL among the wheel speed information as the vehicle body speed V (= vehicle speed V).

  In the turning behavior estimation unit 305, the vehicle body speed V from the vehicle body speed estimation unit 304 and the steering angle from the steering angle sensor 111 are input, the tire turning angle δ is calculated from the steering angle, and a well-known linear two-wheel model Is used to calculate the yaw rate γ and the vehicle body slip angle βv.

The turning resistance calculation unit 306 inputs the yaw rate γ, the vehicle body slip angle βv, and the tire turning angle δ from the turning behavior estimation unit 305, and calculates a front wheel turning resistance force Fcf and a rear wheel turning resistance force Fcr by driver steering. . That is, based on the yaw rate γ, the vehicle body slip angle βv, and the tire turning angle δ, the tire slip angles βf and βr of the front and rear wheels, which are tire side slip angles, are calculated using the following equations.
The front tire slip angle βf and the rear tire slip angle βr are
βf = βv + lf ・ γ / V-δ
βr = βv−lr ・ γ / V
It is calculated by the following formula. Here, lf and lr are distances from the center of gravity of the vehicle body to the front and rear axles.
Then, the tire lateral forces Fyf and Fyr of the front and rear wheels are calculated from the product of the tire slip angles βf and βr of the front and rear wheels and the cornering powers Cpf and Cpr of the front and rear wheels. Further, the front wheel turning resistance force Fcf and the rear wheel turning resistance force Fcr are calculated from the product of the tire slip angles βf and βr of the front and rear wheels and the tire lateral forces Fyf and Fyr of the front and rear wheels.

[Configuration of vehicle vibration estimation unit of vehicle system vibration control device]
Based on FIGS. 3 and 7, the configuration of the vehicle body vibration estimation unit 205 in the three-part vehicle vibration control device 203 will be described.

  The vehicle body vibration estimation unit 205 includes a vehicle model 307 (also referred to as “vibration model”), as shown in FIG. The vehicle model 307 is represented by a motion equation of vehicle body vertical vibration and a motion equation of vehicle body pitching vibration obtained by modeling an actual vehicle (vehicle body, front wheel suspension, rear wheel suspension, etc.) on which this system is mounted. Then, the “drive shaft end torque Tw”, “front and rear wheel vertical forces Ff and Fr”, and “front and rear wheel turning resistance forces Fcf and Fcr” calculated by the input conversion unit 204 are input to the vehicle model 307. Thereby, an estimated value by the vehicle model 307 of the sprung behavior state quantity (bounce speed, bounce quantity, pitch speed, pitch angle) of the vehicle body is calculated.

[Configuration of torque command value calculation unit of vehicle system vibration control device]
Based on FIGS. 3, 8 and 9, the configuration of the torque command value calculation unit 206 in the three-part vehicle system vibration control device 203 will be described.

  As shown in FIG. 3, the torque command value calculation unit 206 includes a first regulator unit 308, a second regulator unit 309, a third regulator unit 310, and a first tuning gain as a correction torque value generation processing configuration. A setting unit 317, a second tuning gain setting unit 318, a third tuning gain setting unit 319, and an adder 320 are provided. Further, as the actuator matching processing configuration of the corrected torque value, a limit processing unit 311, a band pass filter 312, a nonlinear gain amplification unit 313, a limit processing unit 314, and an engine torque conversion unit 315 are provided.

<Correction torque value generation processing configuration>
The first regulator unit 308 provides regulator gains F1 and F2 that suppress the sprung behavior to a minimum with respect to the “sprung behavior by torque input” that is the control target. As shown in FIG. 8, the first regulator unit 308 has a Trq-dZv gain F1 (bounce speed gain), a Trq-dSp gain F2 (pitch speed gain), as shown in FIG. ,give. As shown in FIG. 9, these regulator gains F1 and F2 contribute to the stabilization of the load, the Trq-dZv gain F1 suppresses the bounce speed, and the Trq-dSp gain F2 suppresses the pitch speed.

  The second regulator unit 309 provides regulator gains F3 to F6 that suppress the sprung behavior to the minimum with respect to the “sprung behavior due to disturbance” that is the control target. As shown in FIG. 8, the second regulator unit 309 has a Ws-SF gain F3 (front / rear balance gain) and a Ws-dSF gain F4 (front / rear balance change speed gain) as shown in FIG. Ws-dZv gain F5 (bounce speed gain) and Ws-dSp gain F6 (pitch speed gain) are given. As shown in FIG. 9, these regulator gains F3 to F6 contribute to the stabilization of the load. The Ws-SF gain F3 suppresses the longitudinal load change, and the Ws-dSF gain F4 indicates the longitudinal load change speed. The Ws-dZv gain F5 suppresses the bounce speed, and the Ws-dSp gain F6 suppresses the pitch speed.

  The third regulator unit 310 provides regulator gains F7 and F8 that improve behavior responsiveness due to steering with respect to the “sprung behavior due to steering” that is the object of control. As shown in FIG. 8, the third regulator unit 310 has a Str-dWf gain F7 (front wheel load change speed gain) and a Str-dWr gain F8 (rear wheel load change) as shown in FIG. Speed gain). As shown in FIG. 9, these regulator gains F7 and F8 contribute to the addition of a load. The Str-dWf gain F7 adds a front wheel load, and the Str-dWr gain F8 suppresses rear wheel load fluctuations. .

  The first tuning gain setting unit 317 sets the tuning gain K1 for the Trq-dZv gain F1, as shown in FIG. 8, in order to perform weighting adjustment on the output from the first regulator unit 308, and Trq-dSp Set tuning gain K2 for gain F2. The tuning gains K1 and K2 are values in the positive direction that suppress vibrations, and are values included in the front and rear G fluctuation range that does not give a sense of incongruity. The tuning gains K1 and K2 can be corrected with respect to the preset initial values according to the vehicle state, the traveling state, the driver selection, and the like.

  The second tuning gain setting unit 318 sets a tuning gain K3 with respect to the Ws-SF gain F3 as shown in FIG. 8 in order to perform weighting adjustment on the output from the second regulator unit 309, and Ws-dSF. The tuning gain K4 is set for the gain F4, the tuning gain K5 is set for the Ws-dZv gain F5, and the tuning gain K6 is set for the Ws-dSp gain F6. The tuning gains K3 to K6 are values in the positive direction that suppress vibration and are included in the front-to-back G fluctuation range that does not give a sense of incongruity, like the tuning gains K1 and K2. The tuning gains K3 to K6 can be corrected according to the vehicle state, the traveling state, the driver selection, and the like with respect to the preset initial values.

  The third tuning gain setting unit 319 sets the tuning gain K7 with respect to the Str-dWf gain F7 as shown in FIG. 8 in order to perform weighting adjustment on the output from the third regulator unit 310, and the Str-dWr Set tuning gain K8 for gain F8. Unlike the tuning gains K1 to K6, the tuning gains K7 and K8 are set to values in the negative direction that promote vibration and values that are included in the front and rear G fluctuation range that does not give a sense of incongruity. The tuning gains K7 and K8 can be corrected with respect to the preset initial values according to the vehicle state, the traveling state, the driver selection, and the like.

  The adder 320 performs regulator processing for each behavior to be controlled with respect to the sprung behavior state amount (bounce speed, bounce amount, pitch speed, pitch angle) of the vehicle body calculated by the vehicle body vibration estimation unit 205. Are integrated with the tuning gains K1 to K8, and the sum is calculated to calculate a correction torque value required for the control. This correction torque value is a value obtained by adding the correction torque value A based on the tuning gains K1 and K2, the correction torque value B based on the tuning gains K3 to K6, and the correction torque value C based on the tuning gains K7 and K8.

<Compensation processing configuration for correction torque value>
The limit processing unit 311 performs a maximum value limiting process of the absolute value of the correction torque value on the correction torque value from the adder 320 as a drive system resonance countermeasure, and a torque within a range that the driver does not feel as a G fluctuation. Restrict to.

  The band-pass filter 312 extracts the sprung vibration component of the vehicle body and removes the drive system resonance frequency component so as to suppress the sprung resonance as a countermeasure for the drive system resonance as in the limit processing unit 311. The reason for this is that in an actual vehicle, particularly an engine vehicle, when a vibration component is inadvertently added to the drive torque, vibration that interferes with the drive system resonance may be generated. In addition, an engine vehicle or the like is necessary because there is a possibility that the expected control effect cannot be sufficiently obtained because of poor response to the drive torque command and a dead zone.

  The non-linear gain amplifying unit 313 is used in the vicinity of the correction torque value positive / negative switching region (= actuator dead zone region) as a countermeasure against the response of the actuator (engine 106) to the correction torque value output from the bandpass filter 312. Amplify the correction torque value.

  The limit processing unit 314 performs a final limit process on the corrected torque value output from the nonlinear gain amplification unit 313 after the amplification process.

  The engine torque conversion unit 315 converts the corrected torque value after the limit processing from the limit processing unit 314 into an engine end torque value corresponding to the gear ratio, and outputs this as a final correction torque value.

[Tire displacement nonlinear map correction processing configuration]
The tire displacement nonlinear map correction processing configuration by the nonlinear map correction processing unit 321 will be described with reference to FIGS.

  As shown in FIG. 10, the nonlinear map correction processing unit 321 includes a gradient determining unit 321a, a steady state determining unit 321b, and a nonlinear map correcting unit 321c.

  The gradient determination unit 321a calculates the gradient estimated value SLP, determines that the gradient estimated value SLP exceeds the positive threshold value α, and determines that the gradient is an upward gradient, and if the gradient estimated value SLP falls below the negative threshold value −α, determines that the gradient is a downward gradient. When the threshold value is equal to or greater than the negative threshold value −α and equal to or smaller than the positive threshold value α, the road is determined to be a flat road.

That is, as shown in FIG. 11 (a), in step S301, the gradient estimated value SLP of the own vehicle traveling road is calculated by the following equation (3) that compares the estimated value of the own vehicle acceleration with the actual acceleration.
SLP = [{Tw−Rw (Fa + Fr)} / MvRw] −s · V (3)
However, Tw: Driving shaft end torque, Rw: Tire radius, Fa: Air resistance, Fr: Rolling resistance, Mv: Vehicle weight, s: Laplace operator, V: Vehicle speed.
The air resistance Fa and rolling resistance Fr can be calculated by the following formulas (4) and (5).
Fa = μa · sv · V ² (4)
Fr = μr ・ Mv ・ g (5)
Here, μa: air resistance coefficient, sv: front projected area, μr: rolling resistance coefficient, and g: gravitational acceleration.
In step S302, following the calculation of the gradient estimated value SLP in step S301, it is determined whether or not the gradient estimated value SLP exceeds the positive threshold value α. If it is determined that SLP> α, the process proceeds to step S303. The gradient flag fSLP = 1 (uphill gradient) is determined, and the process proceeds to the end.
In step S304, following the determination that SLP ≦ α in step S302, it is determined whether or not the gradient estimated value SLP is below a negative threshold value −α, and if it is determined that SLP <−α. The process proceeds to step S305, where it is determined that the gradient flag fSLP = 2 (downhill gradient) and the flow proceeds to the end.
In step S306, following the determination that SLP ≧ −α in step S304, it is determined that the gradient flag fSLP = 0 (flat road), and the process proceeds to the end.

  The steady state determination unit 321b determines whether the vehicle is in a steady state traveling at a constant speed based on the accelerator opening speed and the brake operation speed.

  That is, as shown in FIG. 11B, in step S401, it is determined whether or not the accelerator opening speed | ΔACC | is less than the acceleration determination threshold ACC0 for a predetermined time Ta. In the next step S402, it is determined whether or not the brake operation speed | ΔBRK | is less than the deceleration determination threshold BRK0 for a predetermined time Tb. When both the non-acceleration condition in step S401 and the non-deceleration condition in step S402 are satisfied, the process proceeds to step S403, where it is determined that the steady flag fACC = 1 (steady travel) and the process proceeds to the end. On the other hand, when one of the non-acceleration condition in step S401 and the non-deceleration condition in step S402 is not established, the process proceeds to step S404, and it is determined that the steady flag fACC = 0 (unsteady travel) and the process proceeds to the end.

  The nonlinear map correction unit 321c, when the determined estimated gradient shifts from a flat road to a gradient road, or when the estimated gradient shifts from a gradient road to a flat road, the tire displacement nonlinear maps F (MapF), F ( The base point correction value is calculated with MapR) as the changed tire displacement nonlinear map F (MapF), F (MapR).

  That is, as shown in FIG. 12, in step S501, it is determined whether or not the gradient flag fSLP = 0 (flat road). When fSLP = 0, the process proceeds to step S502, and it is determined whether or not the gradient flag fSLP = 1 or 2 (uphill or downhill). If it is determined in step S502 that the gradient flag fSLP = 1 or 2 due to the transition from the flat road to the gradient road, whether or not the steady flag fACC = 1 (steady travel) is determined in the next step S503. Determine whether. When the steady running condition in step S503 is not satisfied, the flow from step S502 to step S503 is repeated, and the tire displacement nonlinear maps F (MapF) and F (MapR) are waited for to be changed. Then, when the steady running condition of step S503 is satisfied, the process proceeds to step S504, and the base point correction values of the tire displacement nonlinear maps F (MapF) and F (MapR) are calculated. When shifting from a flat road to an ascending slope, in step S804, the tire displacement non-linear map (FIG. 14 (c) and FIG. 14 (c)) The base point movement amount up to (b) in FIG. 15 is set as the target movement amount, and a base point correction value that gradually changes over time toward the target movement amount is calculated and output to the suspension stroke calculation unit 302. When shifting from a flat road to a downward slope, in step S504, the base point movement amount from the flat tire displacement nonlinear map to the downward slope tire displacement nonlinear map (FIGS. 14B and 15C). Is used as a target movement amount, and a base point correction value that gradually changes over time toward the target movement amount is calculated and output to the suspension stroke calculation unit 302.

  On the other hand, when the gradient flag fSLP = 1 or 2 (uphill gradient or downhill) in step S501, the process proceeds to step S505, and it is determined whether or not the gradient flag fSLP = 0 (flat road). If it is determined in step S505 that the gradient flag fSLP = 0 because of the transition from the gradient road to the flat road, whether or not the steady flag fACC = 1 (steady running) is determined in the next step S506. to decide. When the steady running condition of step S506 is not satisfied, the flow from step S505 to step S506 is repeated, and the tire displacement nonlinear maps F (MapF) and F (MapR) are waited to be changed. Then, when the steady running condition in step S506 is satisfied, the process proceeds to step S507, and base point correction values for the tire displacement nonlinear maps F (MapF) and F (MapR) are calculated. When shifting from an ascending road to a flat road, in step S507, the tire displacement non-linear map on the flat road (FIG. 14 (a) and FIG. 14 (a)) The base point movement amount up to (a) in FIG. 15 is set as the target movement amount, and a base point correction value that gradually changes over time toward the target movement amount is calculated and output to the suspension stroke calculation unit 302. On the other hand, when shifting from a downhill road to a flat road, in step S507, a flat tire displacement nonlinear map (FIG. 14 (b) and FIG. 15 (c)) is changed from a downhill road tire displacement non-linear map (FIG. 14 (b) and FIG. 15 (c)). The base point movement amount up to a) and FIG. 15 (a)) is set as the target movement amount, and a base point correction value that gradually changes over time toward the target movement amount is calculated and output to the suspension stroke calculation unit 302. .

  The non-linear map correction unit 321c changes the wheel center position due to an assembly error or a secular change in addition to the map correction based on the gradient estimation, whereas the tire displacement non-linear map F (MapF), F (MapR) based on the initial design value. The suspension vertical displacement difference, which is the correction information, is used as the stored value, and the stored value is updated.

  That is, as shown in FIG. 13, in step S601, it is determined whether or not there is a stored value update request by an input from a vehicle connector (DCL) or the like. In addition, the stored value update request is based on the input of measured values that show changes in the suspension characteristics from the vehicle connector (DCL), correction of new cars by input at the vehicle assembly factory, and inspection correction by input from service (market) tools. Is assumed. However, depending on the specifications of the vehicle, the user may input a measurement value from a navigation system or the like (in this case, the input value is constrained for protection against performance degradation). When there is a stored value update request, the process proceeds from step S601 to step S602, and the suspension vertical displacement measurement value is read. Here, the suspension vertical displacement measurement value is a value that indicates a change in the suspension characteristics in the target vehicle, such as the distance from the ground to the vehicle floor (K in FIG. 10), the distance from the wheel center position to the fender arch (in FIG. 10). L) etc.

  In the next step S603, it is determined whether or not the read suspension vertical displacement measurement value is within the normal value range (standard, performance compensation range, design range). Only when the value is within the range, the process proceeds to step S604. In step S604, it is determined whether (front design value−front measurement value) ≧ difference set value or (rear design value−rear measurement value) ≧ difference set value, and at least one of the conditions is satisfied Only proceeds to step S605. In step S605, the suspension vertical displacement difference, which is the vertical displacement difference between the design value and the measured value, is calculated. In the next step S606, the suspension vertical displacement difference is updated as the stored value, and the process proceeds to the end. The stored value is stored in the storage medium in the ECM 1101 by update storage while the vehicle is stationary and stable, and the stored value is continuously used until the next update. The tire displacement nonlinear correction map is derived from the tire displacement nonlinear maps F (MapF) and F (MapR) based on the initial design values stored in advance and the suspension vertical displacement difference that is updated and stored.

Next, the operation will be described.
The functions of the vehicle system vibration control device of the first embodiment are as follows: [vehicle system vibration control processing operation], [travel performance improvement effect exhibited by vehicle system vibration control], [tire displacement nonlinear map correction operation by road surface gradient], [ The tire displacement nonlinear map correction action due to wheel center position change] will be described separately.

[Car system vibration control processing action]
FIG. 16 is a flowchart illustrating a flow of a vehicle system vibration control process executed by the engine control module 101 of the first embodiment. Hereinafter, the vehicle system vibration control processing operation will be described with reference to FIG.

  When the vehicle system vibration control process is started, the driver request torque is calculated by the driver request torque calculation unit 201 in step S1401. In the next step S1402, the drive torque converter 301 adds the gear ratio to the driver request torque, and converts the unit from the engine end torque to the drive shaft end torque Tw. In the next step S1403, the high-pass filter 316 performs filter processing for removing low-order steady components from the wheel speed signals of the wheel speed sensors 103FR, 103FL, 103RR, and 103RL. In the next step S1404, the wheel speed information after the high-pass filter processing by the suspension stroke calculation unit 302, and the front and rear wheel tire non-linear maps F (MapF) and F (F) corrected according to the road surface gradient and the wheel center position change. Based on (MapR), the suspension stroke speed and the suspension stroke amount are calculated. In the next step S1405, the vertical stroke converting unit 303 converts the suspension stroke speed and the suspension stroke amount into the front and rear wheel vertical forces Ff and Fr. In the next step S1406, the steering angle is detected by the steering angle sensor 111. In the next step S1407, the vehicle body speed V is calculated by the vehicle body speed estimation unit 304. In the next step S1408, the turning behavior estimation unit 305 calculates the yaw rate γ and the vehicle body slip angle βv (= vehicle body side slip angle). In the next step S1409, the turning resistance calculating unit 306 calculates front and rear tire slip angles βf, βr (tire slip angles). In the next step S1410, the turning resistance force calculation unit 306 calculates front and rear tire lateral forces Fyf and Fyr. In the next step S1411, the turning resistance calculation unit 306 calculates front and rear wheel turning resistance forces Fcf and Fcr. The above processing is performed in the input conversion unit 204.

  In the next step S1412, the vehicle body vibration estimation unit 205 inputs the drive shaft end torque Tw, the front and rear wheel vertical forces Ff and Fr, and the front and rear wheel turning resistance forces Fcf and Fcr to the vehicle model 307, thereby Behavioral state quantities (bounce speed, bounce quantity, pitch speed, pitch angle) are calculated. In the next step S1413, the tuning gains K1 to K8 are corrected by the vehicle speed, the road surface gradient, and the like. In the next step S <b> 1414, the first tuning gain setting unit 317 calculates a correction torque value A that suppresses vibration due to driver requested torque. In the next step S1415, the second tuning gain setting unit 318 calculates a correction torque value B that suppresses vibration due to disturbance. In the next step S1416, the third tuning gain setting unit 319 calculates a correction torque value C that amplifies fluctuations in the longitudinal load due to steering. In the next step S1417, the adder 320 outputs a correction torque value that is the sum of the correction torque value A, the correction torque value B, and the correction torque value C.

In the next step S1418, the limit processing unit 311 performs drive system resonance countermeasure limit processing on the correction torque value. In the next step S1419, the bandpass filter 312 performs a filter process for removing the drive system resonance component on the correction torque value. In the next step S1420, nonlinear gain processing for amplifying the correction torque value in the vicinity of the positive / negative switching region is performed in the nonlinear gain amplifying unit 313. In the next step S1421, the limit processing unit 314 performs final limit processing on the corrected torque value after amplification processing. In the next step S1422, the engine torque conversion unit 315 converts the drive shaft end correction torque value into an engine end correction torque value, which is output as the final correction torque value.
The vehicle structure vibration control process that proceeds from step S1401 to step S1422 is repeated every predetermined control cycle.

[Driving performance improvement effect demonstrated by vehicle system vibration control]
A basic action for helping understanding of the mechanism by which the sprung behavior of the vehicle body is controlled by executing the vehicle system vibration control process will be described with reference to FIG.

The vehicle system vibration control is a control aiming to stabilize the load and improve the turning performance by suppressing the change speed of the vehicle body behavior due to torque fluctuation or disturbance by correcting the engine torque. Therefore, as a specific running situation, as shown in FIG. 17 (a), a case where the vehicle starts and accelerates from a stop, enters a constant speed state, and then decelerates and stops is taken as an example.
When starting and accelerating from the stop, the driving torque rapidly increases, so that a load movement occurs in which the wheel load of the rear wheel increases and the wheel load of the front wheel decreases, and the vehicle body behavior becomes a nose up in which the front side of the vehicle body is lifted. At this time, as shown in FIGS. 17 (a) and 17 (b), when the driving torque to the rear wheel, which is the driving wheel, is reduced, a nose-down behavior occurs in which the front side of the vehicle body sinks like during deceleration, The nose-up due to load movement and the nose-down due to torque-down cancel each other, and the body behavior is stabilized.
In a steady state where the vehicle enters a constant speed state after starting, control of correcting the driving torque is not performed because the vehicle body behavior is stable. After that, when the vehicle is decelerated and stopped by performing a brake operation or the like, a load movement occurs in which the wheel load of the rear wheel decreases and the wheel load of the front wheel increases due to a sudden decrease in the drive torque. It becomes a nose down where the front side of the car body sinks. At this time, as shown in FIGS. 17 (a) and 17 (b), when the driving torque to the rear wheel, which is the driving wheel, is increased, a nose-up behavior in which the front side of the vehicle body is lifted as during acceleration occurs. The nose-down due to movement and the nose-up due to torque-up cancel each other, and the vehicle behavior becomes stable.
Therefore, looking at the change in the pitch angular velocity of the vehicle body, as shown in FIG. 17C, the solid line characteristic of “with vibration suppression” is smaller in the change of the pitch angular velocity of the vehicle body than the dotted line characteristic of “without vibration suppression”. It will be suppressed.
Hereinafter, the driving performance improvement effect exhibited by performing the vehicle system vibration control will be described by dividing it into <scenes and effects aiming at performance improvement>, <vehicle system vibration control logic>, and <effect confirmation operation>.

<Scenes and effects aimed at improving performance>
Scenes and effects aimed at improving performance through vehicle system vibration control
(a) To obtain a stable linear turning performance with a gentle roll and good linearity in lane changes and scenes such as S-shaped roads.
(b) To obtain stable cruising performance of the vehicle due to the lack of correction steering and good pitch damping in scenes such as high-speed cruising.
It is in. To achieve the effect (a) above, it is necessary to “improve the steering response” and “suppress roll speed”, and to achieve the effect (b) above, it is necessary to “suppress load fluctuation”. It is.

  As shown in FIG. 18, the “improvement of steering response” means that when deceleration = torque down during steering, the front wheel load increases, the cornering power Cp of the front tire increases, and the tire lateral force increases. Thus, the steering response is improved. That is, since the cornering power Cp has a load dependency that increases as the wheel load increases, “increase in steering response” is realized by increasing the wheel load during steering.

  As shown in FIG. 18, for example, when a nose-up behavior occurs, the above-mentioned “inhibition of load fluctuation” causes a motion (nose-down) in the opposite phase to the vehicle body vibration when deceleration = torque down. The load fluctuation is suppressed by canceling the load fluctuation. On the other hand, when nose-down behavior occurs, if acceleration = torque up is performed, motion in the opposite phase to the vehicle body vibration (nose-up) occurs, and load fluctuation is suppressed by offsetting the load fluctuation. The load fluctuation is suppressed both when vibration (load fluctuation) occurs due to driver input and when vibration (load fluctuation) occurs due to road disturbance. That is, “suppression of load fluctuation” is realized by a driving torque having a phase opposite to that of the pitch behavior estimated from the torque fluctuation and the road surface disturbance.

  As shown in FIG. 18, the “roll speed reduction” improves the linearity of the yaw rate by the above-described “improvement of steering response” and “suppression of load fluctuation”. Therefore, the lateral G change is gentle in proportion to the yaw rate, the peak value of the roll rate is reduced, and the roll speed is suppressed. That is, as a result of combining “improvement of steering response” and “suppression of load fluctuation”, “suppression of roll speed” is realized.

<Vehicle system control logic>
The vehicle system vibration control logic that achieves the effects (a) and (b) targeted by the present control will be described with reference to FIG.
As shown in FIG. 19, the vehicle system vibration control logic includes a driver request torque (= drive shaft end torque Tw), front wheel vertical force Ff, rear wheel vertical force Fr, front wheel turning resistance force Fcf, and rear wheel turning resistance force Fcr. , Input to the vehicle model 307. Thereby, the bounce speed, the bounce amount, the pitch speed, and the pitch angle, which are the sprung behavior state quantities of the vehicle body, are calculated.
Then, as shown in FIG. 19, each of the sprung behavior state quantities of the vehicle body is multiplied by regulator gains F1 to F8 that optimize the bounce speed, the bounce amount, the pitch speed, and the pitch angle. Multiply the tuning gains K1 to K8.
With the above processing, correction torque values A, B, and C are obtained for each of the “sprung behavior by torque input”, “sprung behavior by disturbance”, and “sprung behavior by steering”, which are control targets. Then, by adding the correction torque values A, B, and C, a final correction torque value (= control torque in FIG. 19) is obtained, and a drive torque command value for obtaining a drive torque obtained by adding the control torque to the driver request torque is obtained. And output to the engine 106 of the actual vehicle.
Here, among the corrected torque values A, B, and C, the corrected torque value C corrects the driving torque so as to add the front wheel load during steering, and positively applies the wheel load to the left and right front wheels 102FR and 102FL. This is the correction torque value for getting on.

  Therefore, at the time of steering, the yaw response is improved by actively promoting the nose-down behavior so that the front wheel load is increased by the correction torque value C, and at the same time, unnecessary vibration components are suppressed by the correction torque values A and B. This ensures linearity. That is, the effect (a) targeted by the present control for suppressing the roll rate is realized by adding the correction torque value C to the correction torque values A and B.

  On the other hand, among the above correction torque values A, B, and C, the correction torque values A and B stabilize the longitudinal load fluctuation and reduce the vehicle body vibration regardless of the fluctuation of the driving torque and the road surface disturbance during traveling on the straight road. It is a correction torque value to suppress. Therefore, when cruising on a straight road, the pitch behavior, bounce behavior, and front / rear load change due to torque fluctuation and road disturbance are estimated, and the estimated pitch behavior, bounce behavior, and front / rear load change are out of phase with the corrected torque values A and B. When the drive torque is given, the pitch behavior, bounce behavior, and front-rear load change are suppressed. That is, the effect (b) targeted by the present control for obtaining a stable cruise performance of the vehicle is realized by the correction torque values A and B.

<Effect confirmation action>
The effects (a) and (b) aimed by the above control are realized based on FIG. 20, which shows the contrast characteristics (solid line characteristics with control, dotted line characteristics without control) when steering from straight running. The confirming action of being performed will be described.
In the vehicle system vibration control, as indicated by an arrow J in FIG. 20, a control command value (= drive torque command value) is output by (command torque for suppressing vehicle body vibration) + (command torque for controlling steering response). .
For this reason, in the straight traveling region up to the time t1, as shown by the arrow E in FIG. 20, the pitch rate is suppressed as compared to the case without control, and the riding comfort is improved by the stable traveling performance of the vehicle. I understand that.
Then, in the steering transition region after time t1, as shown by the arrow F in FIG. 20, it can be seen that the change in the pitch rate is suppressed and appropriate load movement is realized. As shown by the arrow G in FIG. 20, in the steering transition region, as shown by the arrow G in FIG. 20, it can be seen that the yaw rate rises earlier than in the case of no control, and the initial response is improved. Further, it can be seen that in the steering transition region, in the late turn period, as shown by the arrow H in FIG. 20, the yaw rate changes more gently than in the case of no control, and the turn entrainment is suppressed.
In the steering transition region (from the early turn to the late turn), the control for suppressing the change in the pitch rate and the control for suppressing the change in the yaw rate are performed at the same time. As shown by the arrow I of 20, it can be seen that the roll rate is suppressed as compared with the case of no control.

[Tyre displacement nonlinear map correction action by road surface gradient]
To achieve the desired effects (a) and (b) regardless of the road gradient, the effect of suspension geometry changes due to the road gradient is grasped, and the front wheel vertical force Ff is accurately determined regardless of the road gradient. And a device for calculating the rear wheel vertical force Fr is necessary. Hereinafter, based on FIG.11 and FIG.12, the tire displacement nonlinear map correction | amendment effect | action by the road surface gradient reflecting this is demonstrated.

In Example 1, when the wheel center position of the front and rear wheels is displaced in the vertical direction on a gradient road where the vehicle body posture changes in a stationary state, the front and rear wheel tire displacement nonlinear maps F (MapF) and F (MapR) are represented by the wheel center. A configuration including a non-linear map correction processing unit 321 that corrects in a direction to suppress the displacement is employed.
For example, when the vehicle body position in a stationary state changes due to wheel load movement (small front wheel load, large rear wheel load) on the uphill, and the wheel center position of the rear wheel tire is displaced upward (bound direction), the uphill It moves so that the position which balances in a stationary state may become the base position of a tire displacement nonlinear characteristic. Then, by correcting the movement of the tire displacement nonlinear maps F (MapF) and F (MapR) for the front and rear wheels set based on the initial design value standard, the tire displacement nonlinear maps F (MapF) and F (MapR) are changed to the gradient road. Approximate the tire displacement nonlinear characteristics at.
For this reason, in the suspension stroke calculation unit 302 and the vertical force conversion unit 303 using the tire displacement linear characteristics, the front / rear wheel vertical force, which is a disturbance input based on wheel speed fluctuations, despite the change in the vehicle body posture in a gradient road running scene. The estimation accuracy of Ff and Fr is ensured.
As a result, the slope displacement running scene where the vehicle body posture changes in a stationary state by correcting the movement of the tire displacement nonlinear maps F (MapF) and F (MapR) in a direction that suppresses the wheel center position shift in accordance with the vehicle body posture change. In this case, even if the wheel center position of the front and rear wheels is changed from the balanced position on the flat road due to the slope road, suppression of vehicle body vibration due to disturbance input is ensured.

In the first embodiment, as the nonlinear map correction processing unit 321, the gradient determination unit 321 a that determines ascending gradient, descending gradient, and flat road, and the tire displacement nonlinear maps F (MapF) and F (MapR) are changed based on the gradient determination. A configuration including a non-linear map correction unit 321c to be used is adopted.
That is, in the gradient determination unit 321a, when the gradient estimated value SLP exceeds the positive threshold value α, in the flowchart of FIG. 11A, the process proceeds from step S301 to step S302 to step S303, and the upward gradient (gradient flag fSLP = 1). ). When the estimated slope value SLP falls below the negative threshold value −α, the process proceeds from step S301 to step S302 to step S304 to step S305 in the flowchart of FIG. 11A, and the descending slope (gradient flag fSLP = 2). Determined. Further, when the estimated slope value SLP is greater than or equal to the negative threshold value −α and less than or equal to the positive threshold value α, in the flowchart of FIG. 11A, the process proceeds from step S301 → step S302 → step S304 → step S306. It is determined that the gradient flag fSLP = 0).
When the nonlinear map correction unit 321c determines that a transition from a flat road to a gradient road is made, the flow proceeds to step S501 → step S502 → step S503 → step S504 in the flowchart of FIG. 12, and in step S504, the flat road The tire displacement non-linear map is changed to the tire displacement non-linear map on the slope road. If it is determined that the road is changed from a slope road to a flat road, the process proceeds from step S501 to step S505 to step S506 to step S507 in the flowchart of FIG. Changed to a road tire displacement nonlinear map.
In this way, the road surface gradient is determined by dividing it into three patterns, and the tire displacement nonlinear map F (MapF), F (MapR) is changed based on the gradient determination result, so that it corresponds to the road surface gradient. The tire displacement nonlinear maps F (MapF) and F (MapR) can be changed easily and accurately.

The first embodiment includes a steady state determination unit 321b that determines whether or not a steady state traveling at a constant speed, and the nonlinear map correction unit 321c shifts from a flat road to a gradient road, or When it is determined that the road is shifted to a flat road, a configuration is adopted in which the map change is waited until it is determined to be a steady state.
In other words, generally, when acceleration or deceleration occurs, the gradient estimation accuracy decreases, so if the tire displacement nonlinear map is changed by an incorrect gradient estimated value, the driver is uncomfortable. there is a possibility.
Therefore, in the flowchart of FIG. 11 (b), the steady state (constant speed running) is determined based on the accelerator opening speed | ΔACC | and the brake operation speed | ΔBRK |. In the flowchart of FIG. 12, only when it is determined in step S503 or step S506 that fACC = 1 (steady running), the process proceeds to step S503 → step S504 or step S506 → step S507, and the tire Change the displacement nonlinear map F (MapF), F (MapR).
Therefore, during a run in which the road surface gradient changes in an unsteady state, it waits for a change in the tire displacement non-linear maps F (MapF) and F (MapR) until it is determined to be in a steady state, thereby causing an incorrect slope estimate SLP. By changing the tire displacement nonlinear maps F (MapF) and F (MapR), a sense of incongruity given to the driver is prevented.

In the first embodiment, the gain correction value calculation unit 321d changes the tire displacement nonlinear maps F (MapF) and F (MapR) between the tire displacement nonlinear map on the flat road and the tire displacement nonlinear map on the gradient road. In some cases, a configuration for calculating a base point correction value that gradually changes with time has been adopted.
That is, when the tire displacement nonlinear maps F (MapF) and F (MapR) are changed between a flat road and a slope road, for example, the values of the tire displacement nonlinear maps F (MapF) and F (MapR) are suddenly changed. Then, the total correction torque value may change suddenly, and the vehicle behavior may become unstable.
Therefore, in the flowchart of FIG. 12, when the process proceeds to step S504 or step S507, the modified tire displacement nonlinear map is set as a target value, and the base point correction value that gradually changes with the passage of time from the tire displacement nonlinear map before the change. Is calculated.
Therefore, in the driving scene in which the tire displacement nonlinear maps F (MapF) and F (MapR) are changed between the flat road and the slope road, the vehicle behavior is calculated by calculating the base point correction value that gradually changes with time. Stability is ensured.

[Tire displacement nonlinear map correction effect by wheel center position change]
In order to realize the effects (a) and (b) aimed at by this control regardless of the change from the initial design value of the wheel center position, grasp the change effect on the tire displacement nonlinear map due to the change of the wheel center position. However, it is necessary to devise a method for accurately calculating the front wheel vertical force Ff and the rear wheel vertical force Fr. Hereinafter, based on FIG. 13, FIG. 21 to FIG. 24, the tire displacement nonlinear map correction action by the wheel center position change reflecting this will be described.

For example, the tire displacement nonlinear map F (MapF), F (MapR) determined by the initial design value of the wheel center position is given as a comparative example.
In the case of this comparative example, as shown in FIG. 21, the wheel center position changes from the initial design value due to assembly errors in the factory production line or aging due to continuous use for many years, and the vehicle height (suspension geometry) is reduced. Changes occur.
In view of this, the case where the wheel center position changes from the initial stage of production in which the wheel center position is in the design value state after market entry is taken as an example. In this case, as shown in FIG. 22, the wheel center position is determined according to the rear wheel tire displacement nonlinear characteristics from the initial stage of production, the balance position K (initial design value position), in a certain vehicle state and timing after market launch. To the balance position L (change position from the design value position).

  Therefore, in the comparative example in which the tire displacement nonlinear maps F (MapF) and F (MapR) are provided by the fixed map based on the initial design value, the tire displacement nonlinearity increases as the width of the wheel center position changes from the initial design value. Since the approximation with respect to the characteristics is reduced and the accuracy of calculating the front and rear wheel vertical forces Ff and Fr calculated as disturbance inputs is reduced, the effect of suppressing vehicle body vibration against disturbance inputs cannot be expected.

On the other hand, in Example 1, when the wheel center position in a flat road stationary state has changed from the design position, the tire center non-linear maps F (MapF) and F (MapR) of the front and rear wheels are shifted to the wheel center position. A configuration including a non-linear map correction processing unit 321 that corrects in a direction to suppress the above is adopted.
For example, when the wheel center position of the rear tire is displaced upward (bound direction) from the design position, the balance position L (FIG. 23) in the displaced state becomes a balance position of the tire displacement nonlinear characteristics. The tire displacement nonlinear characteristic is moved as indicated by an arrow M in FIG. And by correcting the front and rear wheel tire non-linear maps F (MapF) and F (MapR) to be maps based on the characteristics after movement, the difference between the true tire non-linear characteristics and the tire non-linear correction map The tire displacement nonlinear map is suppressed to be smaller than that of the comparative example in which the fixed map is used, and the characteristic approximation is improved when the wheel center position is changed from the design position.
For this reason, the estimation accuracy of the front and rear wheel vertical forces Ff and Fr, which are disturbance inputs based on wheel speed fluctuations, is ensured despite the change of the wheel center position from the design position in a flat road stationary state.
As a result, if the wheel center position changes from the design position, the disturbance displacement nonlinear map F (MapF), F (MapR) is corrected in the direction to suppress the wheel center position deviation, so that the disturbance input that displaces the suspension. Even when the wheel center position is changed from the design position in the traveling scene, suppression of vehicle body vibration due to disturbance input is ensured.

In the first embodiment, the nonlinear map correction processing unit 321 reads a suspension vertical displacement measurement value in which the change in the suspension characteristic in the target vehicle can be understood, and a displacement difference is generated in the suspension vertical displacement measurement value with respect to the initial design value. A configuration that corrects the tire displacement nonlinear maps F (MapF) and F (MapR) in the direction to suppress the wheel center position deviation was adopted.
That is, in the flowchart of FIG. 13, the process proceeds from step S601 to step S602 to step S603 to step S604. In step S604, (front design value−front measurement value) ≧ difference set value or (rear design value−rear Only when at least one of the conditions of (measured value) ≧ difference set value is satisfied, the process proceeds to step S605 and subsequent steps.
Therefore, when reading the suspension vertical displacement measurement value, if there is a displacement difference with respect to the initial design value, the tire displacement nonlinear map F (MapF), with good response without waiting for confirmation of the occurrence of the displacement difference multiple times. F (MapR) is corrected.

In the first embodiment, when the tire displacement nonlinear map correction process is executed as the nonlinear map correction processing unit 321 based on the reading of the suspension vertical displacement measurement value, the suspension vertical displacement difference is updated and stored as a saved value. Then, the suspension stroke calculation unit 302 employs a configuration in which disturbance input is estimated based on wheel speed fluctuations using the updated and stored values as tire displacement nonlinear map correction information.
That is, in the flowchart of FIG. 13, the process proceeds from step S601 to step S602 → step S603 → step S604 → step S605. When the suspension vertical displacement difference is calculated in step S605, the suspension vertical movement is determined in the next step S606. The displacement difference is updated as a saved value.
Therefore, when corrected, the suspension vertical displacement difference is updated and stored as a stored value, and immediately reflected in the estimation of disturbance input, thereby correcting the tire displacement nonlinear maps F (MapF) and F (MapR). The estimation accuracy of the front and rear wheel vertical forces Ff and Fr, which are disturbance inputs with good response, is ensured.

In the first embodiment, the nonlinear map correction processing unit 321 employs a configuration in which the suspension vertical displacement difference is updated and stored as a saved value in a state where the vehicle is stationary and stable.
That is, in the flowchart of FIG. 13, when the process proceeds from step S601 to step S602, step S603, step S604, step S605, and step S606, it is confirmed in step S606 that the vehicle is stationary and stable. Then, the suspension vertical displacement difference is updated as the stored value.
Therefore, as in the case of changing the tire displacement nonlinear map F (MapF), F (MapR) during driving, the vehicle behavior is reliably prevented from becoming unstable due to a sudden change in the correction torque value accompanying the map change. Is done.

In the first embodiment, the nonlinear map correction processing unit 321 includes a measurement value information determination unit (step S603) that determines whether or not the read suspension vertical displacement measurement value is within the normal value range. When the measured value is outside the normal value range, a configuration is adopted in which the tire displacement nonlinear map correction information is not updated as the stored value.
That is, in the flowchart of FIG. 13, in step S603, it is determined whether or not the read suspension vertical displacement measurement value is within the normal value range (standard, performance compensation range, design range), and is outside the normal value range. When judged, go to the end.
Therefore, when the suspension vertical displacement measurement value is out of the normal range due to erroneous measurement etc., the correction of the tire displacement nonlinear map F (MapF), F (MapR) is prohibited, and the driver can correct the tire displacement nonlinear map by mistake. It is avoided that the user feels uncomfortable.

In the first embodiment, the nonlinear map correction processing unit 321 employs a configuration in which a suspension vertical displacement difference that is a displacement difference between an initial design value and a suspension vertical displacement measurement value is calculated, and the suspension vertical displacement difference is updated and stored as a saved value. did.
That is, in the flowchart of FIG. 13, in step S605, the suspension vertical displacement difference is calculated, and in the next step S606, the suspension vertical displacement difference is updated as a saved value. Then, when the suspension vertical displacement difference is stored, as shown in FIG. 24, a point P where the tire displacement nonlinear maps F (MapF) and F (MapR) intersect based on the design value standard is obtained, and the tire displacement before the movement is obtained. As shown by the arrow R, the map axis base point correction is performed to move the base point Q of the nonlinear maps F (MapF) and F (MapR) to the intersection point Q obtained from the suspension vertical displacement difference. By this map axis base point correction, a tire displacement nonlinear correction map for the front and rear wheels is created.
Therefore, since the initial design values of the tire displacement nonlinear maps F (MapF) and F (MapR) are pre-stored information, the initial design value and the suspension vertical displacement difference can be simply updated and stored. A tire displacement nonlinear correction map is acquired by the map axis base point correction process according to the above.

Next, the effect will be described.
In the vehicle system vibration control device of the first embodiment, the effects listed below can be obtained.

(1) An input conversion unit 204 that converts sensing information from the vehicle acquired during traveling into wheel input; a vehicle body vibration estimation unit 205 that estimates the sprung behavior of the vehicle body using the wheel input and the vehicle model 307; In the vehicle system vibration control device, comprising a torque command value calculation unit 206 that corrects the drive torque based on the estimation result of the sprung behavior,
The input conversion unit 204 uses a tire displacement nonlinear map in which a relationship characteristic of a vertical displacement with respect to a longitudinal displacement of a wheel center position based on a suspension geometry is used, and a disturbance input that estimates a disturbance input based on a wheel speed variation An estimation unit (suspension stroke calculation unit 302, vertical force conversion unit 303),
When the wheel center position is changed from the design position in a stationary state on a flat road, the disturbance input estimation unit (suspension calculation unit 302, vertical force conversion unit 303) changes the tire displacement nonlinear map F (MapF), F ( A non-linear map correction processing unit 321 that corrects (MapR) in a direction that suppresses the wheel center position shift is provided (FIG. 3).
For this reason, in a disturbance input travel scene in which the suspension is displaced, even if the wheel center position changes from the design position, it is possible to ensure suppression of vehicle body vibration due to disturbance input.

(2) The nonlinear map correction processing unit 321 reads a suspension vertical displacement measurement value in which the change in the suspension characteristic in the target vehicle is known, and when a displacement difference occurs in the suspension vertical displacement measurement value with respect to the initial design value, The tire displacement nonlinear map is corrected in a direction to suppress the wheel center position deviation (FIG. 13).
For this reason, in addition to the effect of (1), if the displacement difference is generated with respect to the initial design value when reading the suspension vertical displacement measurement value, the response is good without waiting for confirmation of the occurrence of the displacement difference multiple times. The tire displacement nonlinear maps F (MapF) and F (MapR) can be corrected.

(3) When the nonlinear map correction processing unit 321 corrects the tire displacement nonlinear map F (MapF), F (MapR) based on the reading of the suspension vertical displacement measurement value, the tire displacement nonlinear map correction information (suspension vertical displacement difference) ) As a stored value,
The disturbance input estimation unit (suspension calculation unit 302, vertical force conversion unit 303) estimates the disturbance input based on wheel speed fluctuation using the updated stored value as tire displacement nonlinear map correction information ( FIG. 13).
For this reason, in addition to the effect of (2), when the tire displacement nonlinear map F (MapF), F (MapR) is corrected, it is immediately reflected in the estimation of the disturbance input, so that the tire displacement nonlinear map F (MapF) , F (MapR) correction processing, it is possible to ensure the estimation accuracy of the front and rear wheel vertical forces Ff and Fr which are disturbance inputs with good response.

(4) When the non-linear map correction processing unit 321 updates and stores the tire displacement non-linear map correction information (suspension vertical displacement difference) as a stored value, the non-linear map correction processing unit 321 performs the operation while the vehicle is stationary and stable (FIG. 13).
For this reason, in addition to the effect of (3), the vehicle behavior is unstable due to a sudden change in the correction torque value accompanying the map change, as in the case of changing the tire displacement nonlinear maps F (MapF), F (MapR) during driving. Can be reliably prevented.

(5) The nonlinear map correction processing unit 321 includes a measurement value information determination unit (step S603) for determining whether or not the read suspension vertical displacement measurement value is a value within a normal range. When the measured value is outside the normal range, the tire displacement nonlinear map correction information is not updated as the stored value (FIG. 13).
For this reason, in addition to the effect of (3) or (4), correction of tire displacement nonlinear maps F (MapF) and F (MapR) is prohibited when the suspension vertical displacement measurement value is outside the normal value range due to erroneous measurement etc. By doing so, it is possible to avoid giving the driver a sense of incongruity due to erroneous tire displacement nonlinear map correction.

(6) The nonlinear map correction processing unit 321 calculates a suspension vertical displacement difference that is a displacement difference between the initial design value and the suspension vertical displacement measurement value, and updates and stores the suspension vertical displacement difference as a saved value (FIG. 13). Step S605 → Step S606).
For this reason, in addition to the effects of (3) to (5), only the suspension vertical displacement difference is updated and stored, and the tire displacement nonlinear correction is performed by the map axis base point correction process based on the initial design value stored in advance and the suspension vertical displacement difference. A map can be obtained.

  As mentioned above, although the vehicle system vibration control device of the present invention has been described based on the first embodiment, the specific configuration is not limited to the first embodiment, and the invention according to each claim of the claims. Design changes and additions are permitted without departing from the gist of the present invention.

  In the first embodiment, as the nonlinear map correction processing unit 321, an example in which nonlinear map correction processing is performed in accordance with the gradient determination value (uphill and downhill) and the change of the wheel center position from the design position in a flat road stationary state. Indicated. However, as shown in FIG. 25, the non-linear map correction processing includes “design value equivalent”, “no vehicle tilt”, “vehicle tilting backward”, “vehicle tilting forward”, “vehicle tilting large”, and “vehicle It may be an example that is divided into “large forward tilt”. Moreover, it is good also as an example which performs only the nonlinear map correction | amendment process according to the change from the design position of a wheel center position.

  In the first embodiment, an example in which the drive shaft end torque Tw, the front and rear wheel vertical forces Ff and Fr, and the front and rear wheel turning resistance forces Fcf and Fcr are calculated as input information to the vehicle model 307 as the input conversion unit 204 is shown. It was. However, any input conversion unit may be used as long as it calculates at least the front and rear wheel vertical forces Ff and Fr as disturbance inputs.

  In the first embodiment, an example in which a state quantity represented by a bounce speed, a bounce amount, a pitch speed, and a pitch angle is used as the sprung behavior of the vehicle body estimated by the vehicle body vibration estimation unit 205 is shown. However, the sprung behavior of the vehicle body estimated by the vehicle body vibration estimation unit may be one of pitch behavior, bounce behavior, or a combination of these behaviors as a state quantity.

  In the first embodiment, an example in which the engine 106 is used as an actuator that outputs a control command value has been described. However, an actuator, such as a motor as a power source, a continuously variable transmission, a friction clutch, etc., is provided in the drive system and can control the drive torque transmitted to the drive wheels by an external command. It ’s fine.

  In the first embodiment, an example in which the sprung behavior of the vehicle body is estimated using the vehicle model 307 as the vehicle body vibration estimation unit 205 is shown. However, the vehicle body vibration estimation unit may be an example in which estimation is performed using one or a plurality of equations of motion corresponding to a vehicle model.

  In the first embodiment, an example of the MT transmission 107 that manually changes the transmission gear stage is shown as the transmission. However, the transmission may be an example of an automatic transmission that automatically changes the transmission gear stage and the gear ratio.

  In the first embodiment, the vehicle system vibration control device of the present invention is applied to an engine vehicle. However, the vehicle system vibration control device of the present invention can of course be applied to a hybrid vehicle or an electric vehicle. Furthermore, in the case of a hybrid vehicle, the response performance in the torque command value calculation unit of the vehicle system vibration control device may be switched between an engine travel mode and a motor travel mode with different actuators (power sources).

101 Engine control module (ECM)
102FR, 102FL Left and right front wheels (driven wheels)
102RR, 102RL Left and right rear wheels (drive wheels)
103FR, 103FL, 103RR, 103RL Wheel speed sensor
104 Brake stroke sensor
105 Accelerator position sensor
106 engine
107 MT transmission
108 shaft
109 Differential gear
110 Steering wheel
111 Steering angle sensor
201 Driver required torque calculation section
202 Torque command value calculator
203 Vehicle control system
204 Input converter
205 Body vibration estimation unit
206 Torque command value calculator
301 Drive torque converter
302 Sustain stroke calculation unit (disturbance input estimation unit)
303 Vertical force converter (disturbance input estimator)
304 Body speed estimation part
305 Turning behavior estimation unit
306 Turning resistance calculation unit
307 Vehicle model
308 First regulator
309 Second regulator
310 Third regulator
311 Limit processing section
312 Bandpass filter
313 Nonlinear Gain Amplifier
314 Limit processing section
315 Engine torque converter
316 high pass filter
317 First tuning gain setting section
318 Second tuning gain setting section
319 Third tuning gain setting section
320 Adder
321 Nonlinear map correction processor
321a Gradient judgment part
321b Steady state determination unit
321c Nonlinear Map Correction Unit

Claims (6)

An input conversion unit that converts sensing information from the vehicle acquired during traveling into wheel input, a vehicle body vibration estimation unit that estimates the sprung behavior of the vehicle body using the wheel input and the vehicle model, and the sprung behavior In a vehicle system vibration control device comprising a torque command value calculation unit for correcting drive torque based on an estimation result,
The input conversion unit uses a tire displacement nonlinear map in which a relationship characteristic of a vertical displacement with respect to a longitudinal displacement of a wheel center position based on a suspension geometry is mapped, and a disturbance input estimation that estimates a disturbance input based on a wheel speed variation Part
The disturbance input estimation unit is provided with a non-linear map correction processing unit that corrects the tire displacement non-linear map in a direction to suppress the wheel center position deviation when the wheel center position in a flat road stationary state changes from the design position. A vehicle system vibration control device characterized by this. In the vehicle system vibration control device according to claim 1,
The non-linear map correction processing unit reads a suspension vertical displacement measurement value in which a change in the suspension characteristics in the target vehicle can be recognized, and when a displacement difference occurs in the suspension vertical displacement measurement value with respect to an initial design value, a wheel center position deviation is detected. A vehicle structure vibration control device that corrects a tire displacement nonlinear map in a direction that suppresses vibration. In the vehicle system vibration control device according to claim 2,
The nonlinear map correction processing unit updates and stores the tire displacement nonlinear map correction information as a saved value when the tire displacement nonlinear map correction processing is executed based on reading the suspension vertical displacement measurement value,
The disturbance input estimation unit estimates disturbance input based on wheel speed fluctuation using the updated stored value as tire displacement nonlinear map correction information. In the vehicle system vibration control device according to claim 3,
The non-linear map correction processing unit, when updating and storing tire displacement non-linear map correction information as a stored value, is performed in a state where the vehicle is stopped and stable. In the vehicle system vibration control device according to claim 3 or 4,
The nonlinear map correction processing unit includes a measurement value information determination unit that determines whether the read suspension vertical displacement measurement value is within a normal range, and the suspension vertical displacement measurement value is outside the normal range. In such a case, the vehicle structure vibration control device is characterized in that the tire displacement nonlinear map correction information is not updated as a stored value. In the vehicle system vibration control device according to any one of claims 3 to 5,
The non-linear map correction processing unit calculates a suspension vertical displacement difference which is a displacement difference between an initial design value and a suspension vertical displacement measurement value, and updates and stores the suspension vertical displacement difference as a saved value. Vibration control device.