JP5402731B2 - Actuator control device - Google Patents

Description

  The present invention relates to an actuator operation control device for operating and controlling an actuator for controlling the operation of a wheel traveling on a road surface based on a distance between the sensor detected by a preview sensor attached to the vehicle and the road surface. About.

  Based on the distance between the sensor detected by the preview sensor and the road surface, a so-called preview control (preview control) that controls the operation of an actuator for controlling the vertical movement of a wheel traveling on the road surface, for example, an actuator of an active suspension. )It has been known.

  During preview control, for example, a preview sensor (distance sensor or the like) installed in front of the vehicle detects the distance from the sensor mounting position to the road surface position where the vehicle is scheduled to travel. Further, based on the detected distance, the operation of the actuator of the suspension connected to the wheel is controlled when the wheel travels on the preview position, which is the road surface position to be detected when the distance is detected. Control information (for example, a vertical displacement amount (a road surface displacement amount) from the reference position at the preview position) is acquired. Then, the operation of the actuator is controlled based on the acquired control information.

  In preview control, control information at a plurality of preview positions obtained for each sampling time is temporarily stored in, for example, a memory (RAM or register) of the suspension ECU. Then, the actuator is operated and controlled based on the control information read from the memory at an appropriate timing in anticipation of the compensation time indicating the control delay of the actuator.

  Patent Document 1 discloses an active suspension control device that stores a road surface displacement amount as control information at a thinning rate according to a vehicle speed, and that can execute preview control without requiring useless memory capacity.

  Further, Patent Document 2 discloses a method of performing preview control using a memory in which a storage area for control information is divided according to a vehicle speed range. According to this, the storage area of the control information in the memory is divided for each of a plurality of vehicle speed areas. In addition, the road surface displacement data sampling cycle stored in the divided region corresponding to the range where the vehicle speed is high is shorter than the data sampling cycle of the road surface displacement amount stored in the divided region corresponding to the range where the vehicle speed is low, respectively. A sampling period is set for each area. Further, each divided region is configured such that the number of data stored (saved) in the divided region corresponding to the range where the vehicle speed is high is larger than the number of data stored in the divided region corresponding to the range where the vehicle speed is low. The By doing so, the road surface displacement amount is recorded evenly with respect to the entire vehicle speed.

JP-A-4-342612 JP-A-9-136522

  The time obtained by dividing the distance (preview distance) between the preview position and the wheel scheduled to travel at the preview position (control target wheel position) by the vehicle speed is a margin time until the wheel travels at the preview position. Represents. If this margin time is less than the compensation time indicating the delay in controlling the actuator for controlling the operation of the wheel, the control is not in time, and the actuator cannot be controlled at an appropriate timing.

  According to the conventional control device including the active suspension control device described in the above patent document, the preview position is located immediately below the preview sensor. That is, the ground angle, which is the angle formed by the exit direction of the detection medium such as the ultrasonic wave emitted by the preview sensor and the road surface, is almost a right angle. In this case, especially when the wheel to be controlled is the front wheel, the preview distance is relatively short. Therefore, when the vehicle speed is high, the margin time is likely to be shorter than the control delay time.

  In order to extend the preview distance, the detection medium may be emitted obliquely forward from the preview sensor so that the preview position is more forward than the current position of the vehicle. That is, the preview distance can be extended by attaching the preview sensor to the vehicle so that the ground angle is an acute angle when viewed from the vehicle side. However, when the ground angle of the preview sensor is an acute angle, the preview position varies greatly depending on the pitch motion of the vehicle.

  FIG. 29 is a diagram in which the difference in the amount of change in the preview position due to the pitch motion is compared between when the reference ground angle is 90 ° and when it is 30 °. In the figure, the preview sensor is mounted 500 mm above the road surface. This figure also illustrates the amount of change in the preview position when the vehicle posture is pitched by 2 ° from a horizontal state (pitch angle = 0 °). When the reference ground angle of the preview sensor is 90 °, the preview position changes by 17.5 mm due to a pitch angle change of 2 °. On the other hand, when the reference ground angle of the preview sensor is 30 °, the preview position changes by 74.3 mm due to a pitch angle change of 2 °. Assuming that the vehicle is traveling at 80 km / h, the vehicle is about 3.3 msec. And travel 74.3mm. This means that when the actuator is operated at an appropriate timing, the pitch movement causes 3.3 msec. This suggests the possibility of a timing shift. The sampling period of the signal detected by the preview sensor is 3.3 msec. In the following cases, the amount of timing deviation described above is larger than the sampling period, so that in some cases, necessary control information is lacking. This deteriorates the control performance of the preview control.

  FIG. 30 is a graph showing temporal changes in the preview position when the ground angle is set to an acute angle (for example, 30 °) when viewed from the vehicle side. According to this graph, when no pitch motion is generated, the preview position advances (increases) in the traveling direction of the vehicle over time. However, when a pitch motion occurs in which the front of the vehicle sinks, the preview position does not advance in the traveling direction of the vehicle with time, and the preview position temporarily retracts (decreases).

  Control information used for preview control is stored (saved) in the order of sampling time (calculation order) in, for example, a shift register. That is, the storage position of the control information in the memory is determined in the order of the sampling time. And when reading control information, it reads in order of sampling time. However, as shown in FIG. 30, when the pitch motion occurs, the preview position may move backward as time elapses. In this case, if the control information is read out in the order of the sampling time, the control information is not read out in the order of the road surface through which the wheel to be controlled passes. This deteriorates the control performance of the preview control.

  The present invention has been made to cope with the above-described problem, and an actuator that controls the operation of an actuator for controlling the operation of a controlled wheel that travels on a planned traveling road surface based on a distance detected by a preview sensor. It is an object of the present invention to provide an actuator operation control device in which deterioration of control performance of preview control is effectively suppressed.

  The present invention includes a preview sensor that is attached to a vehicle and detects a distance from the attachment position to a road surface position where the vehicle is scheduled to travel every preset sampling time, and the distance detected by the preview sensor In the actuator operation control device for controlling the operation of the actuator for controlling the operation of the wheel that travels the preview position which is the road surface position that is the detection target when the distance is detected, Travel distance calculation means for calculating the travel distance of the vehicle based on the travel speed, and the preview position and its preview that are detected when the distance is detected based on the distance detected by the preview sensor This is the distance from the road surface position where the wheel to be controlled, which is the wheel that is scheduled to travel, is currently in contact with the ground. Based on a preview distance calculating means for calculating a preview distance, a preview position calculating means for calculating the preview position based on a value obtained by adding the preview distance to the travel distance of the vehicle, and a distance detected by the preview sensor. Necessary to control the operation of the actuator for controlling the operation of the wheel to be controlled when the wheel to be controlled travels the preview position that is the object of detection when the distance is detected. Control information calculating means for calculating control information as information, a memory having a plurality of storage locations for storing the control information calculated by the control information calculating means, and the preview position calculated by the preview position calculating means Based on the preview position when the wheel to be controlled travels Storage position calculation means for calculating a storage position representing a storage location in the memory of the control information calculated by the control information calculation means as information necessary for controlling the operation of an actuator for controlling the operation; and the memory An actuator operation control device comprising: control information recording means for recording the control information in a storage location represented by a storage position calculated by the storage position calculation means.

  According to the actuator operation control device provided by the present invention, based on the distance detected by the preview sensor, the preview position indicating the position of the road surface that is the detection target when the distance is detected is controlled. When the wheel travels, control information necessary for controlling the operation of the actuator for controlling the operation of the wheel to be controlled, for example, a road surface displacement amount at the preview position, is calculated. The control information calculated in this way is recorded in the memory. Further, since the control information is calculated based on the distance detected for each sampling time by the preview sensor, a plurality of control information at different preview positions is recorded in the memory. The storage position representing the storage location of each control information in the memory is calculated by the storage position calculation means. In this case, based on the preview position, the storage position calculation means controls as information necessary for controlling the operation of the actuator that controls the operation of the control target wheel when the control target wheel travels at the preview position. The storage position of the control information calculated by the information calculation means is calculated. That is, the storage position of the control information is calculated based on the preview position where the control information is required. Then, the control information is recorded in the storage location represented by the calculated storage position. Thus, according to the present invention, the storage position of the control information is not determined in order of the sampling time, but the storage position of the control information is determined based on the preview position.

  Since the storage position of the control information at the preview position in the memory is determined based on the preview position, a relationship is given between the storage position of the control information and the preview position where the control information is required. . For example, the preview position where the control information A calculated first is 1.5 m, the preview position where the control information B calculated next is 1.4 m, and the control information C calculated last. Consider the case where the required preview position is 1.6 m. In the conventional storage system, the control information is recorded in the calculation order (A, B, C order) and read in that order (A, B, C order). For this reason, the control information (control information A) at the preview position far from the traveling vehicle is read out earlier than the control information (control information B) at the near preview position. Therefore, a situation occurs in which the control information is not read in the order of the road surface through which the control target wheel passes, and as a result, the control performance of the preview control deteriorates. On the other hand, according to the present invention, the storage position of the control information at the preview position is calculated based on the preview position so that a relationship is given between the storage position of the control information and the preview position. For example, the storage position is calculated so as to increase as the preview position increases. Accordingly, the control information B at the preview position 1.4 m is represented by the storage position 3 and the control information A at the preview position 1.5 m is represented by the storage position 3. Control information C at the preview position 1.6 m is recorded in each storage location. Then, according to the relevance at the time of reading the control information, for example, in the above example, the control information is read in ascending order of the preview position by reading out the control information in order from the smaller storage position.

  That is, according to the present invention, at the time of recording control information, the storage position of each control information is reconfigured based on the preview position. Since the storage position of the control information is determined based on the preview position in this way, even if the preview position changes due to a posture change such as a pitch motion of the vehicle, it is represented by the storage position based on the change. Control information at the preview position is recorded in a memory location. Therefore, even when the preview position moves backward with time due to the pitch movement of the vehicle, the control information can be read in the order of the preview position based on the storage position related to the preview position. Thereby, deterioration of the control performance of the preview control can be suppressed.

  The actuator controlled by the operation control device of the present invention may be any actuator as long as it is an actuator for controlling the operation of the wheel to be controlled. For example, the operation control device of the present invention is applied to an actuator used for an active suspension or an actuator for changing a characteristic (damping coefficient) of a damping force generated by a shock absorber using a viscous fluid used for a passive suspension. Can be applied. These actuators control the vertical movement of the wheel to be controlled. Further, for example, the operation control device of the present invention can be applied to an actuator (for example, an electric motor) for rotating or braking the wheel to be controlled. In this case, the actuator controls the rotation operation of the wheel to be controlled.

  The control information may be any information as long as it is information necessary for controlling the operation of the actuator for controlling the operation of the control target wheel when the control target wheel travels in the preview position. For example, when the actuator is an actuator of an active suspension, the control information may be a road surface displacement amount (vertical displacement amount from the reference position) at the preview position, or the actuator outputs according to the road surface displacement amount. The target control force to be used may be used. Further, when the actuator is an actuator for changing the damping force characteristic of a shock absorber attached to each wheel, the control information may be the road surface displacement amount or according to the road surface displacement amount. The target damping force to be output from the shock absorber, or the target driving force or target driving amount of the actuator necessary for generating the target damping force in the shock absorber may be used. Further, when the actuator is an actuator for rotationally driving or braking the wheel to be controlled, the control information may be the road surface displacement amount or a target to be output by the actuator according to the road surface displacement. It may be a driving force or a target braking force. In other words, the control information is any information as long as it is derived based on the distance detected by the preview sensor and is necessary for deriving the control amount to be finally output by the actuator to be controlled. good.

  The preview sensor emits a detection medium such as an ultrasonic wave or a laser beam toward a road surface, and detects a distance between the preview position and the sensor mounting position based on a reflected wave or reflected light from the preview position. Any sensor can be used as long as the distance can be detected.

  The travel distance calculating means calculates the distance traveled by the vehicle from the start of control to the present. The travel distance calculating means preferably calculates the travel distance of the vehicle by multiplying the travel speed and travel time of the vehicle. In this case, the travel distance of the vehicle may be calculated by accumulating the product of the travel speed of the vehicle and the sampling time.

  The preview distance calculating means may calculate the preview distance based on the distance detected by the preview sensor and the amount representing the mounting angle and mounting position of the preview sensor when the distance is detected. For example, the preview distance can be calculated from the distance detected by the preview sensor and the ground angle of the preview sensor when the distance is detected. Also, the preview distance can be calculated from the distance detected by the preview sensor and the height from the road surface of the preview sensor when the distance is detected.

  The ground angle of the preview sensor may be an acute angle when viewed from the vehicle side. By attaching the preview sensor to the vehicle so that the ground angle becomes an acute angle, the preview distance can be extended. As a result, even if the traveling speed of the vehicle is high, the margin time can be made longer than the control delay time. In addition, when the ground angle is set to an acute angle as described above, the preview position varies greatly due to a change in the posture of the vehicle. In this case, the effect of the present invention is sufficiently exhibited by applying the present invention.

  Note that when the ground angle of the preview sensor is set to an acute angle when viewed from the vehicle side, the preview position changes greatly. Therefore, in order to accurately obtain the greatly changing preview position, the actuator operation control device of the present invention is provided with a preview. It is preferable to provide posture change amount acquisition means for acquiring the change amount of the sensor mounting posture. This posture change amount acquisition means may include means for acquiring a change amount of the ground angle of the preview sensor and means for acquiring a height change amount of the preview sensor from the road surface.

  The storage position calculation means is based on the preview position so that the storage position (address) of the memory representing the storage location of the control information is associated with the preview position where the control information is required. The storage position where the control information is to be recorded is calculated. Preferably, the storage position is calculated so that the larger the preview position, the larger (or smaller) the number (address number) representing the storage position, that is, the control information is arranged in order of the preview position. Thus, by calculating the storage position and reading out the control information in the order of the storage position, it is possible to control the operation of the actuator in order from the side with the smallest preview position.

  Further, the actuator operation control device of the present invention multiplies the traveling speed of the vehicle by a preview compensation time set in advance as a delay time related to the operation control of the actuator. Preview compensation distance calculation means for calculating a preview compensation distance, which is a distance traveled by the vehicle, and a road surface on which the vehicle travels after the preview compensation time has elapsed based on a value obtained by adding the preview compensation distance to the travel distance of the vehicle. Preview compensation position computing means for computing a preview compensation position representing a position, and readout position computing means for computing, as a readout position, a storage position calculated based on the preview position corresponding to the preview compensation position by the storage position computing means And among the storage locations in the memory, the read position calculation means Ri based on the recorded control information in a memory location represented by the calculated read position, and the control amount calculation means for calculating a control amount for controlling the operation of the actuator, further may be provided with.

  According to this, the storage position calculated by the storage position calculation means based on the preview position corresponding to the preview compensation position is calculated as the reading position. Then, a control amount for controlling the operation of the actuator is calculated based on the control information recorded in the storage location represented by the calculated read position. The actuator is controlled to operate based on the control amount thus calculated.

  The preview compensation distance is a length obtained by converting a preview compensation time, which is predetermined as a control delay time for compensating for the delay time due to the response time and communication time of the actuator and the internal filter, into a distance. The operation of the actuator that has started operation at the point where the vehicle is currently traveling (current position) is just completed when the vehicle has traveled to the preview compensation position. Therefore, by operating the actuator based on the control amount obtained based on the control information at the preview compensation position, the operation of the actuator can be completed at an appropriate timing. In addition, since the preview compensation distance is not affected by the pitch motion of the vehicle, the preview compensation distance advances (increases) over time even when the posture of the vehicle changes. Therefore, the control information can be read in the order of the preview position based on the preview compensation distance.

  Further, the storage position calculating means calculates the storage position based on the preview position and a tire ground contact length that is a length along a vehicle traveling direction of a portion where the wheel to be controlled is in contact with a traveling road surface. It is good to calculate. In particular, the storage position may be calculated based on a value obtained by dividing the preview position by the tire ground contact length. Similarly, the reading position calculation means may calculate the reading position based on the preview compensation position and the tire ground contact length. In particular, the read position is preferably calculated based on a value obtained by dividing the preview compensation position by the tire ground contact length.

  According to this, by calculating the storage position based on the value obtained by dividing the preview position by the tire contact length, the storage position changes every time the preview position changes by the tire contact length. That is, every time the preview position changes by the tire contact length, the control information at the preview position is stored in a different storage position. This indicates that the road surface interval in which the control information is recorded is the tire contact length. When the road surface interval in which the control information is recorded is shorter than the tire contact length, there arises a problem that the storage capacity of the storage area increases. In addition, since the road surface change in the section shorter than the tire contact length may be ignored when the tire gets over the change, it is not necessary to memorize such a road surface change in the minute section. . On the other hand, when the road surface interval in which the control information is recorded is longer than the tire contact length, the control information is insufficient and the riding comfort deteriorates. For these reasons, by setting the road surface interval in which the control information is recorded as the tire contact length, it is possible to suppress an increase in storage capacity and to store the control information at an optimal distance interval that is not excessive or insufficient.

  In this case, the distance detection interval by the preview sensor, that is, the sampling period (sampling time) can be detected every time the vehicle travels at least by the tire contact length even when the vehicle is traveling at high speed. It is good to be set to.

  Further, the travel distance calculating means is configured to determine the vehicle based on the travel speed of the vehicle and the maximum preview distance so that the travel distance of the vehicle repeatedly varies within a range not exceeding a preset maximum preview distance. It is preferable to calculate the travel distance. In this case, the travel distance calculating means is configured to calculate the travel distance of the vehicle at each sampling time, and the vehicle is operated during the sampling time by multiplying the sampling time and the travel speed of the vehicle. Unit travel distance calculation means for calculating the unit travel distance traveled, and the travel distance present value obtained by adding the unit travel distance to the previous travel distance calculated as the travel distance of the vehicle previously calculated is the maximum preview distance. A travel distance determination means for determining whether or not the travel distance determination means determines that the travel distance current value is equal to or less than the maximum preview distance. And when the travel distance determination unit determines that the travel distance current value is larger than the maximum preview distance, Further may be provided with travel distance setting means for setting a value obtained by subtracting the maximum preview distance from the row distance this value to the travel distance of the vehicle.

  According to this, since the travel distance of the vehicle repeatedly fluctuates within a range not exceeding the maximum preview distance, the preview position calculated based on the sum of the travel distance of the vehicle and the preview distance is also the maximum preview distance. It fluctuates repeatedly within the range of the length represented by Further, since the storage position calculation means calculates the storage position based on the preview position, the calculated storage position repeatedly fluctuates within a range corresponding to the maximum preview distance. This means that the memory location is used repeatedly each time the preview position changes by the maximum preview distance. For example, when the maximum preview distance is 2.0 m and the preview position on the actual road surface is 0 m to 2 m, the control information is stored in the storage location represented by the recording position 0 to the recording position 19, respectively. Even when the preview position on the actual road surface is 2 m to 4 m, the control information is stored in the storage locations represented by the recording position 0 to the recording position 19, respectively. In this way, by configuring so that the same storage location is repeatedly used for each maximum preview distance, a large amount of control information can be recorded with a small recording capacity.

  The storage position calculation means calculates the storage position based on a value obtained by dividing the preview position by the tire contact length when the preview position is equal to or less than the maximum preview distance, and the preview position is When the maximum preview distance is exceeded, the storage position may be calculated based on a value obtained by subtracting the maximum preview distance from the preview position divided by the tire contact length. Similarly, when the preview compensation position is equal to or less than the maximum preview distance, the readout position calculation means calculates the readout position based on a value obtained by dividing the preview compensation position by the tire contact length, When the preview compensation position exceeds the maximum preview distance, the readout position is calculated based on a value obtained by dividing the preview compensation position by subtracting the maximum preview distance by the tire contact length. Good.

  The actuator operation control apparatus according to the present invention further comprises control information erasing means for erasing the control information recorded in a storage location representing a road surface that has already traveled out of the control information recorded in the memory. It is good to be. Control information about the road surface that has already traveled is not necessary for future control. Therefore, by erasing such control information, new control information can be recorded in the storage location represented by the storage location that has become free.

  In this case, the actuator operation control apparatus according to the present invention provides a maximum preview compensation distance, which is an upper limit value of the preview compensation distance, based on a storage position representing a storage location from which the control information has been deleted by the control information deletion unit. Maximum preview compensation distance calculating means for calculating, and preview compensation distance upper limit guard means for setting the preview compensation distance to the maximum preview compensation distance when the preview compensation distance exceeds the maximum preview compensation distance. It is good.

It is the schematic of the system configuration | structure of the suspension apparatus which concerns on this embodiment. FIG. 3 is a partial cross-sectional schematic view of a suspension body. It is a partial section schematic diagram showing the internal structure of an actuator. It is a figure which shows an example of the attachment state of the preview sensor to a sprung member. It is a block diagram which shows the control structure of the electric motor by suspension ECU and a drive circuit. It is a block diagram which shows the internal structure of suspension ECU. It is a block diagram showing CPU for every function structure. It is a figure which shows the structure of RAM. It is a figure which shows the state from which the height and ground angle of a preview sensor change when a sprung member carries out the pitch motion. It is a figure which shows the state from which the height of a preview sensor changes when a sprung member roll-moves. It is a figure which shows the state from which the height of a preview sensor changes, when a sprung member carries out heave motion. It is a figure which shows the relationship between the ground angle of a preview sensor, sensor height, the distance detected by a preview sensor, and the road surface displacement amount in a preview position. It is a figure showing the relationship between a ground angle and the distance detected by a preview sensor. It is a flowchart which shows the flow of a travel distance calculation routine. It is a flowchart which shows the flow of a data recording routine. It is a flowchart which shows the flow of a preview compensation distance calculation routine. It is a flowchart which shows the flow of a data read routine. It is a figure showing the correspondence of a preview position and a data storage position. It is the figure which represented the maximum preview distance as a virtual distance on the storage area of RAM. It is a conceptual diagram of the storage area of RAM. It is the figure which contrasted the road surface displacement amount recorded in each storage position of the storage area of RAM, and the correction road surface displacement amount with the actual road surface displacement. It is the figure which showed the state by which the data of a road surface displacement amount are recorded on the storage area of RAM by the preview control of this embodiment with the driving state of a vehicle. It is a graph which shows the required time resolution of the road surface displacement amount currently recorded on the storage area of RAM. It is the figure which contrasted the sampling time used by the preview control by the conventional method, the number of the data memorize | stored, and the number of the data memorize | stored by the preview control by this embodiment. It is a block diagram showing CPU for every function structure. It is a block diagram showing CPU for every function structure. It is a block diagram showing CPU for every function structure. It is another example of a road surface shape calculation routine. It is the figure which compared the difference in the variation | change_quantity of the preview position by pitch motion in the case where a ground angle is 90 degrees and the case of 30 degrees. It is a graph showing the time change of a preview position when the ground angle is set to an acute angle when viewed from the vehicle side.

  Hereinafter, a suspension device including an actuator operation control device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a system configuration of a suspension apparatus according to the present embodiment.

  This suspension apparatus includes four sets of suspension bodies 10FR, 10FL, 10RR, and 10RL, and a suspension ECU 50 that controls the operations of the suspension bodies 10FR, 10FL, 10RR, and 10RL. The four suspension bodies 10FR, 10FL, 10RR, and 10RL include an unsprung member and a vehicle body B (sprung member) connected to each wheel (right front wheel WFR, left front wheel WFL, right rear wheel WRR, left rear wheel WRL). Are provided respectively. In the present specification, the positions where the suspension bodies 10FR, 10FL, 10RR, 10RL are attached to the vehicle body B are referred to as wheel positions (right front wheel position, left front wheel position, right rear wheel position, left rear wheel position). Hereinafter, the four sets of the suspension bodies 10FR, 10FL, 10RR, and 10RL and the wheels WFR, WFL, WRR, and WRL are simply collectively referred to as the suspension body 10 and the wheels W unless otherwise distinguished from front, rear, left, and right.

  FIG. 2 is a schematic view of the suspension body 10. As shown in FIG. 2, the suspension body 10 includes a coil spring 20 and an actuator 30 arranged in parallel. The coil spring 20 is provided between the lower arm LA connected to the wheel W and the vehicle body B, absorbs an impact received from the road surface, enhances riding comfort, and elastically supports the vehicle body B. A member on the upper side of the coil spring 20, that is, the vehicle body B side is referred to as a “sprung member”, and a member on the lower side of the coil spring 20, that is, the wheel W side is referred to as a “unsprung member”. Therefore, the coil spring 20 and the actuator 30 are provided between the sprung member and the unsprung member of the vehicle.

  FIG. 3 is a partial cross-sectional schematic diagram showing the internal structure of the actuator 30. As shown in FIG. 3, the actuator 30 includes an electric motor 31 that is a drive source, and a ball screw mechanism 35 that converts the rotational motion of the electric motor 31 into a linear motion. The electric motor 31 includes a motor casing 311, a hollow rotating shaft 312, a permanent magnet 313, and a pole body 314. The motor casing 311 is formed in a cylindrical shape having an upper surface, a lower surface, and a side peripheral surface, and constitutes an outer wall of the electric motor 31. The rotating shaft 312 is disposed in the motor casing 311 and is rotatably supported by the motor casing 311 by a bearing 331. A permanent magnet 313 is fixed to the outer peripheral surface of the rotating shaft 312. The rotating shaft 312 and the permanent magnet 313 constitute a rotor of the electric motor 31. A pole body 314 (with a coil wound around a core) is fixed to the inner peripheral surface of the motor casing 311 so as to face the permanent magnet 313. The pole body 314 constitutes the stator of the electric motor 31.

  The ball screw mechanism 35 includes a ball screw 36 and a ball screw nut 38 that is screwed into a male screw portion 37 formed on the ball screw 36. The rotation of the ball screw 36 is restricted by the anti-rotation mechanism 40 while its axial movement is allowed. The ball screw nut 38 is connected to the lower end of the rotating shaft 312 at the upper end surface thereof, and supported by the motor casing 311 by the bearing 332 so as to be able to rotate integrally with the rotating shaft 312. Therefore, when the ball screw 36 moves linearly along the axial direction, the linear motion is converted into rotational motion of the ball screw nut 38 and the rotating shaft 312. Conversely, when the rotary shaft 312 rotates, this rotational driving force is transmitted to the ball screw nut 38, and the rotational motion of the ball screw nut 38 is converted into a linear motion of the ball screw 36.

  As shown in FIG. 2, the lower end of the ball screw 36 is connected to the lower arm LA. The lower arm LA is an unsprung member connected to the wheel side. That is, the ball screw 36 is connected to the unsprung member side. A mounting bracket 41 is connected to the motor casing 311 of the electric motor 31. An upper support 42 made of an elastic material connected to the vehicle body B is attached to the upper surface of the mounting bracket 41. As can be seen from such a connection structure, the electric motor 31 and the ball screw nut 38 connected to the rotor of the electric motor 31 are connected to the vehicle body B side, that is, the sprung member side, via the upper support 42.

  The actuator 30 expands and contracts as the ball screw 36 moves in the axial direction. As the actuator 30 expands and contracts, the wheel connected to the actuator 30 via the unsprung member moves up and down. Further, by controlling the expansion / contraction operation of the actuator 30, the vertical operation of the wheel connected to the actuator 30 is controlled.

  The coil spring 20 is interposed between an annular retainer 43 provided on the outer peripheral surface of the ball screw 36 connected to the unsprung member (lower arm LA) and a mounting bracket 41 connected to the sprung member (vehicle body B). Be dressed.

As shown in FIG. 1, each sprung acceleration sensor 61, vehicle speed sensor 62, and preview sensors 63R, 63L are attached to the vehicle. Sprung acceleration sensor 61 is disposed at each wheel position of the sprung member acceleration (acceleration on each ring spring) along the vertical direction at each wheel position of the sprung member to detect the G _b. The sprung acceleration sensor 61 detects, for example, an upward acceleration as a positive acceleration and a downward acceleration as a negative acceleration. The vehicle speed sensor 62 detects the traveling speed V of the vehicle.

  The preview sensors 63R and 63L are distance sensors, and detect the distance from the sensor mounting position to the measurement object (the road surface position in the present embodiment). The preview sensor 63R is attached in the vicinity of the right front end of the sprung member, and detects the distance between the road surface (scheduled road surface) on which the right front wheel WFR and the right rear wheel WRR are scheduled to travel and the sensor 63R mounting position. The preview sensor 63L is attached to the position of the left front end of the sprung member, and detects the distance between the planned road surface position of the left front wheel WFL and the left rear wheel WRL and the attachment position of the sensor 63L. In the following description, when the preview sensors 63R and 63L are not distinguished, they are collectively referred to as the preview sensor 63. The distance between the road surface position detected by the preview sensor 63 and the sensor mounting position is referred to as a sensor distance, and when the sensor distance is detected, the road surface position for which the distance is detected is referred to as a preview position.

In the present embodiment, the preview sensor 63 can be configured to include, for example, a transmitter that emits ultrasonic waves, a receiver that receives ultrasonic waves, and a distance calculation circuit. The distance calculation circuit calculates the sensor distance for each preset sampling time T _s based on the time required for the ultrasonic wave emitted from the transmitter to be reflected at the preview position and received by the receiver. Is calculated.

FIG. 4 is a diagram illustrating an example of the attachment state of the preview sensor 63 to the sprung member (vehicle body). As shown in the figure, the preview sensor 63 is attached to the front surface of the vehicle body B (sprung member). Further, the ground angle θ representing the angle formed between the emission direction of the ultrasonic wave emitted from the preview sensor 63 and the road surface is an acute angle when viewed from the vehicle side, that is, the detection medium from the preview sensor 63 is oblique to the vehicle. The preview sensor 63 is attached to be inclined with respect to the road surface so as to be emitted forward. The ground angle θ can be set to 30 degrees, for example, but is not limited thereto. As shown in the drawing, the preview sensor 63 detects a sensor distance _{z_ssr} that is a distance between the preview position and the mounting position of the sensor 63.

  As shown in FIG. 1, each sprung acceleration sensor 61, vehicle speed sensor 62, and preview sensor 63 are electrically connected to the suspension ECU 50. The suspension ECU 50 is electrically connected to a drive circuit 70 provided for each suspension body 10. Each electric motor 31 of each actuator 30 of each suspension body 10 is controlled by the suspension ECU 50 via each drive circuit 70. Each drive circuit 70 is electrically connected to a power storage device 110 such as an in-vehicle battery.

  FIG. 5 is a block diagram showing a control configuration of the electric motor 31 by the suspension ECU 50 and the drive circuit 70. The drive circuit 70 constitutes a three-phase inverter circuit, and switching elements SW11, SW12, SW21, respectively corresponding to the three-phase electromagnetic coils CL1, CL2, CL3 of the electric motor 31 (a three-phase brushless motor is used in this embodiment). SW22, SW31, SW32. These switching elements are duty-controlled based on a control signal from the suspension ECU 50 (PWM control). As a result, the amount of current supplied from the battery to the electric motor 31 and the amount of regenerative power sent from the electric motor 31 to the battery are controlled.

  FIG. 6 is a block diagram showing an internal configuration of the suspension ECU 50. Based on the sensor distance detected by the preview sensor 63, the suspension ECU 50 is an actuator 30 attached to the vehicle to move the control target wheel that travels on the road surface (planned road surface) where the sensor distance is detected. Control the operation of The suspension ECU 50 and the preview sensor 63 correspond to the actuator operation control device of the present invention. As shown in the figure, the suspension ECU 50 includes an input interface 51, a CPU 52, a ROM 53, a RAM 54, an output interface 55, and a bidirectional bus 56. The input interface 51, CPU 52, ROM 53, RAM 54, and output interface 55 are connected to each other by a bidirectional bus 56. The input interface 51 is electrically connected to each sensor, and is configured to transmit a signal from each sensor to the CPU 52. The CPU 52 is configured to execute a routine (program) for controlling the operation of the actuator 30. The ROM 53 stores in advance a routine (program) executed by the CPU 52 and tables, parameters, and the like that are referred to when the CPU 52 executes the routine. The RAM 54 is configured to temporarily store data as necessary when the CPU 52 executes a routine. The RAM 54 corresponds to the memory of the present invention. The output interface 55 outputs a control signal for controlling the operation of each actuator 30 to each drive circuit 70.

  FIG. 7 is a block diagram showing the CPU 52 for each functional configuration. As shown in the figure, the CPU 52 includes a state amount calculation unit 521, a position change amount calculation unit (posture change amount acquisition unit) 522, a travel distance calculation unit (travel distance calculation unit) 523, and a preview compensation distance calculation unit (preview compensation). Distance calculation means) 524, road surface shape calculation section (control information calculation means) 525, preview distance calculation section (preview distance calculation means) 526, data recording section 527, data reading section 528, target control force calculation section (control amount calculation means) 529.

The state quantity calculation unit 521 calculates a physical quantity necessary for the calculation executed in the CPU 52, in particular, a physical quantity related to the posture change of the sprung member. In the present embodiment, the state quantity calculation unit 521 calculates the displacement amount from the reference position along the vertical direction at each wheel position of the sprung member. The position change amount calculation unit 522 calculates the amount of change in the attachment posture of the preview sensor 63 accompanying the change in posture of the sprung member. The travel distance calculation unit 523 calculates a travel distance S of the vehicle that fluctuates within a maximum preview distance L _{p_max} that is a preset distance. The preview compensation distance calculation unit 524 calculates a preview compensation distance L _c that is a value obtained by converting a preview compensation time T _p that is a time necessary for compensating for a control delay such as an operation response time of the actuator 30 into a distance. The road surface shape calculation unit 525 calculates the road surface displacement amount (height displacement amount from the reference position) _{x_road} at the preview position.

The preview distance calculation unit 526 calculates a preview distance L _p that is a distance between the preview position and the road surface position where the wheel to be controlled is currently in contact with the ground. Here, the wheel to be controlled is a wheel that is scheduled to travel on the planned traveling surface whose distance is detected by the preview sensor 63. The control target wheels corresponding to the preview sensor 63R are the right front wheel WFR and the right rear wheel WRR, and the control target wheels corresponding to the preview sensor 63L are the left front wheel WFL and the left rear wheel WRL. The present embodiment shows an example in which the front wheels are controlled wheels.

The data recording unit 527 calculates a position (storage position i) where the road surface displacement amount _{x_road} calculated by the road surface shape calculation unit 525 is stored in the RAM _54, and also changes the road surface displacement to the storage location represented by the calculated storage position i. Record the quantity _{x_road} . The data reading unit 528 calculates a storage position (reading position n) representing a place where the amount of road surface displacement to be read from the RAM 54 is stored, and also stores the road surface displacement stored in the storage position represented by the calculated reading position n. calculating a corrected road displacement x _{_Road_c} by interpolating the amount _x _road. The target control force calculation unit 529 calculates a target control force F to be output by the actuator 30 of each suspension body 10 based on the corrected road surface displacement amount _{x_road_c,} and outputs a control signal based on the calculated target control force F. Output.

FIG. 8 is a diagram showing the configuration of the RAM 54. As shown in the figure, the RAM 54 has a storage area 541 for storing a plurality of road surface displacement amounts. In this storage area 541, for example, a plurality of storage locations where storage locations (addresses) are represented by numbers 0 to 19 are provided. Then, the road surface displacement amount _{x_road} calculated by the road surface shape calculation unit 525 is recorded in the storage location represented by the determined storage position.

In such a configuration, when the suspension ECU 50 controls the operation of each actuator 30, first, the state quantity calculation unit 521 in the CPU 52 receives the sprung acceleration at each wheel position from each sprung acceleration sensor 61 (each wheel spring on acceleration) enter the G _{b_i,} by integrating this second floor, it computes the each wheel sprung displacement x _{b_i} representing the vertical displacement amount from a reference position in each wheel position of the sprung member. Here, subscript i of the code x _{b_i} representing the sign G _{b_i} and Kakuwa sprung displacement representative of the acceleration each ring spring represents the wheel for each wheel position of the sprung member. Therefore, the subscript i is any one of the right front wheel fr, the left front wheel fl, the right rear wheel rr, and the left rear wheel rl. In other words, the state quantity calculation unit 521 performs second-order integration of the right front wheel sprung acceleration G _{b_fr} detected from the sprung acceleration sensor 61 installed at the right front wheel position, thereby causing the sprung displacement amount (right Front wheel sprung displacement amount) x _{b_fr} and left front wheel sprung acceleration G _{b_fl} detected by a sprung acceleration sensor 61 installed at the left front wheel position are integrated by second order integration. Front wheel sprung displacement amount) x _{b_fl} and right rear wheel sprung acceleration G _{b_rr} detected from sprung acceleration sensor 61 installed at the right rear wheel position by second-order integration, the sprung displacement amount at the right front wheel position (Right rear wheel sprung displacement amount) x _{b_rr} is obtained by integrating the left rear wheel sprung acceleration G _{b_rl} detected from the sprung acceleration sensor 61 installed at the left rear wheel position by second-order integration. Sprung displacement (left rear wheel bar The upper _{displacement)} x b_rl, computed respectively.

  Note that the amount of each sprung displacement can be obtained by other methods. For example, each sprung displacement is based on a detection value by an unsprung acceleration sensor that detects the acceleration along the vertical direction of each unsprung member and a detection value by a stroke sensor that detects the amount of expansion / contraction (stroke displacement) of each actuator 30. You may ask for the quantity. Further, the amount of sprung displacement may be estimated by designing the observer and obtaining the observer gain.

Further, the position change amount calculation unit 522 calculates the sensor height change amount _{dH_ssr} and the ground angle change amount _{dθ_ssr} . The sensor height change amount _{dH_ssr} is a change amount ( _{H_ssr−} H ₀ ) of the height _{H_ssr} from the road surface to the preview sensor 63 with respect to the reference height H ₀ . The ground angle change amount _{dθ_ssr} is a change amount (θ _{_ssr} −θ ₀ ) of the ground angle θ _{_ssr} of the preview sensor 63 with respect to the reference ground angle θ ₀ .

  For example, when the sprung member performs pitch motion, roll motion, or heave motion while the vehicle is running, the height from the road surface of the preview sensor 63 attached to the front of the sprung member and the ground angle of the preview sensor 63 change with the motion. To do.

FIG. 9 is a diagram illustrating a state in which the height and the ground angle of the preview sensor 63 change when the sprung member performs a pitch motion. In the figure, when the vehicle is in a horizontal state (when the pitch angle = 0 °), the ground angle of the preview sensor 63 is the reference ground angle θ ₀ . When the vehicle performs a pitch motion from the horizontal state by the angle θ _P , the pitch angle θ _P is a difference between the reference ground angle θ ₀ and the actual ground angle θ _{_ssr} (θ _P = θ ₀ −θ _{_ssr} ). Therefore, the pitch angle θ _P corresponds to the ground angle change amount _{dθ_ssr} .

（１）式において、dH_{P_ssr}はピッチ運動によるセンサ高さの変化量、dH_{R_ssr}はロール運動によるセンサ高さの変化量、dH_{H_ssr}はヒーブ運動によるセンサ高さの変化量である。車両が標準状態（ピッチ運動、ロール運動およびヒーブ運動が発生していない状態）であるときにおけるプレビューセンサ６３の高さを基準高さH₀と定義した場合、車両が姿勢変化したときにおけるプレビューセンサ６３の高さH_{_ssr}は、基準高さH₀に高さ変化量dH_{_ssr}を加算することにより求められる。 FIG. 10 is a diagram showing a state in which the height of the preview sensor 63 changes when the sprung member rolls. FIG. 11 is a diagram illustrating a state in which the height of the preview sensor 63 changes when the sprung member performs a heave motion. As can be seen from FIGS. 9 to 11, the height of the preview sensor 63 varies depending on the pitch motion, roll motion and heave motion of the sprung member. Therefore, the height change amount _{dH_ssr} can be expressed as the following equation (1).

(1) In the equation, dH _{P_ssr} amount of change in the sensor height by pitch motion, dH _{R_ssr} amount of change in the sensor height by roll motion, dH _{H_ssr} is the change amount of the sensor height by heave motion. When the height of the preview sensor 63 when the vehicle is in a standard state (a state in which pitch motion, roll motion, and heave motion are not generated) is defined as the reference height H ₀ , the preview sensor when the vehicle changes its posture the height H _{_Ssr} of 63 is obtained by adding the height variation dH _{_Ssr} the reference height H _0.

上記（２）式において、Laは、車両を側方から見た場合におけるバネ上部材の重心位置Oからプレビューセンサ６３が配置されている位置A（図９参照）までの距離、θ_Pはピッチ角度、αは、車両を側方から見た場合における重心位置Oとプレビューセンサ６３の配置位置Aとを通る線分OAとバネ上部材の重心位置Oを通り且つ車両前後方向に水平に伸びる線分OS1とのなす角である（図９参照）。 The sensor height change amount _{dHP_ssr} due to the pitch motion can be obtained by, for example, the following equation (2).

In the above equation (2), La is the distance from the center of gravity O of the sprung member when the vehicle is viewed from the side to the position A (see FIG. 9) where the preview sensor 63 is disposed, and θ _P is the pitch. The angle α is a line extending horizontally in the vehicle front-rear direction through the line segment OA passing through the center of gravity O when the vehicle is viewed from the side and the position A of the preview sensor 63 and the center of gravity O of the sprung member. This is the angle formed by the minute OS1 (see FIG. 9).

上記（３）式において、Lbは、車両を前後方向から見た場合におけるバネ上部材の重心位置Oからプレビューセンサ６３が配置されている位置B（図１０参照）までの距離、θ_Rはロール角度、βは、車両を前後方向から見た場合における重心位置Oとプレビューセンサ６３の配置位置Bとを通る線分OBとバネ上部材の重心位置Oを通り且つ車両左右方向に水平に伸びる線分OS2とのなす角である（図１０参照）。 The change amount dH _{R_ssr} of the sensor height due to the roll motion is obtained by, for example, the following equation (3).

In the above equation (3), Lb is the distance from the center of gravity O of the sprung member when the vehicle is viewed from the front-rear direction to the position B (see FIG. 10) where the preview sensor 63 is disposed, and θ _R is the roll The angle β is a line extending horizontally in the vehicle left-right direction through the line segment OB passing through the center of gravity O when the vehicle is viewed from the front-rear direction and the position B of the preview sensor 63 and the center of gravity S of the sprung member. This is the angle formed by the minute OS2 (see FIG. 10).

上記（４）式において、Lはホイールベース、L_Fはバネ上部材の重心位置から前輪軸位置までの前後方向距離、L_Rはバネ上部材の重心位置から後輪軸位置までの前後方向距離、x_{b_F}は右前輪バネ上変位量x_{b_fr}または左前輪バネ上変位量x_{b_fl}、x_{b_R}は右後輪バネ上変位量x_{b_rr}または左後輪バネ上変位量x_{b_rl}である。プレビューセンサ６３Ｒについてヒーブ運動によるセンサ高さ位置変化量dH_{H_ssr}を演算する場合は、右前輪バネ上変位量x_{b_fr}と右後輪バネ上変位量x_{b_rr}をそれぞれx_{b_F}，x_{b_R}に代入する。プレビューセンサ６３Ｌついてヒーブ運動によるセンサ高さ位置変化量dH_{H_ssr}を演算する場合は、左前輪バネ上変位量x_{b_fl}と左後輪バネ上変位量x_{b_rl}をそれぞれx_{b_F}，x_{b_R}に代入する。 The change amount dH _{H_ssr} of the sensor height due to the heave motion is obtained by, for example, the following equation (4).

In the above equation (4), L is the wheel base, L _F is the longitudinal distance from the center of gravity of the sprung member to the front wheel shaft position, L _R is the longitudinal distance from the center of gravity of the sprung member to the rear wheel shaft position, x _{b_F} is the right front wheel sprung displacement amount x _{b_fr} or the left front wheel sprung displacement amount x _{b_fl} , and x _{b_R} is the right rear wheel sprung displacement amount x _{b_rr} or the left rear wheel sprung displacement amount x _{b_rl} . When the sensor height position change amount dH _{H_ssr} due to the heave motion is calculated for the preview sensor 63R, the right front wheel sprung displacement amount x _{b_fr} and the right rear wheel sprung displacement amount x _{b_rr} are substituted into x _{b_F} and x _{b_R} , respectively. When calculating the sensor height position change amount dH _{H_ssr} due to the heave motion for the preview sensor 63L, the left front wheel sprung displacement amount x _{b_fl} and the left rear wheel sprung displacement amount x _{b_rl} are substituted into x _{b_F} and x _{b_R} , respectively.

The pitch angle theta _P and roll angle theta _R can be expressed as by using the displacement amount x _{b_i} each ring spring for example, the following (5) and (6).

In the above equation (5), when calculating the pitch angle θ _P for the preview sensor 63R, the right front wheel sprung displacement amount x _{b_fr} and the right rear wheel sprung displacement amount x _{b_rr} are substituted into x _{b_F} and x _{b_R} , respectively. . When calculating the pitch angle θ _P for the preview sensor 63L, the left front wheel sprung displacement amount x _{b_fl} and the left rear wheel sprung displacement amount x _{b_rl} are substituted into x _{b_F} and x _{b_R} , respectively. In the above equation (6), T is the tread of the vehicle.

The travel distance calculation unit 523 calculates a travel distance S of the vehicle that represents the distance traveled by the vehicle up to the present time based on the travel speed V of the vehicle. Specifically, the travel distance calculation unit 523 repeatedly executes the travel distance calculation routine shown in FIG. 14 every sampling time T _s . When this routine is started, first, the travel distance calculation unit 523 detects the preset sampling time (cycle) T _s and vehicle speed sensor 62 in step (hereinafter abbreviated as “S”) 100 in the figure. The unit travel distance ds traveled by the vehicle per sampling time T _s is calculated by multiplying the travel speed V of the vehicle (unit travel distance calculation means). Then, at S102, by adding the unit travel distance ds to the travel distance S that has been previously calculated, it calculates a travel distance present value S ₀ as the cumulative distance of the unit travel distance ds.

Then, the travel distance calculator 523, in S104, (travel distance determining means) determines the travel distance present value S ₀ is whether greater than the maximum preview distance L _{P_MAX.} The maximum preview distance L _{p_max} is a preview distance that is a distance between a preview position that is a target road surface position when the preview sensor 63 detects the sensor distance _{z_ssr} and a front wheel that is scheduled to travel on the road surface. L _{p is} the upper limit, and can be set arbitrarily. The maximum preview distance L _{p_max} is _preferably larger than the preview distance L _p acquired when the vehicle is traveling on a flat road surface. For example, the maximum preview distance L _{p_max} is set to 2.0 m.

When the travel distance current value S ₀ is equal to or less than the maximum preview distance L _{p_max} (S104: No), the travel distance current value S ₀ is directly set as the travel distance S of the vehicle in S108 (travel distance setting means). Thereafter, this routine is terminated. On the other hand, if the travel distance current value S ₀ is greater than the maximum preview distance L _{p_max} (S104: Yes), the vehicle travel distance S is _obtained by subtracting the maximum preview distance L _{p_max} from the travel distance current value S _{0 in} S106. (Travel distance setting means). Thereafter, this routine is terminated. The travel distance S of the vehicle calculated by executing such a travel distance calculation routine increases from 0 as the vehicle travels. When the maximum preview distance L _{p_max} is _exceeded , the value returns to 0 again, and then increases again as the vehicle travels. That is, the travel distance S of the vehicle repeatedly increases within a range not _exceeding the maximum preview distance L _{p_max} .

Road shape calculating section 525, sensor distance z _{_Ssr} and detected by the preview sensor 63, and inputs the sensor height change amount calculated by the position change amount calculating portion 522 dH _{_ssr} and ground angle variation dθ _{_ssr.} Then, based on the input value, when the sensor distance _{z_ssr} is detected, the road surface displacement amount _{x_road} at the preview position which is the road surface position to be detected is calculated. The road surface displacement amount _{x_road} is a vertical displacement amount from the reference position of the traveling road surface. In the present embodiment, for example, the operation of the actuator 30 of the suspension body 10 connected to the wheel is controlled according to the amount of displacement of the road surface on which each wheel travels so that the vehicle can ensure a good ride comfort when traveling. The Therefore, this road surface displacement amount is necessary for controlling the operation of the actuator 30 that is connected to the control target wheel and controls the operation of the control target wheel when the control target wheel travels in the preview position having the road surface displacement amount. Information. The road surface displacement amount _{x_road} corresponds to the control information of the present invention.

FIG. 12 is a diagram illustrating a relationship between the ground angle _{θ_ssr} , the sensor height _{H_ssr} , the sensor distance _{z_ssr,} and the road surface displacement amount _{x_road} at the preview position where the sensor distance _{z_ssr} is detected. As can be seen from the figure, the following equation (7) is established between them.

路面形状演算部５２５は、上記（８）式に基づいて、路面変位量x_{_road}を演算する。 In the above equation (7), the ground angle θ _{_ssr} is represented by the reference ground angle θ ₀ and the pitch angle θ _P (= dθ _{_ssr} ), and the sensor height H _{_ssr} is represented by the reference height H ₀ and the height change amount dH _{_ssr.} The Therefore, the road surface displacement amount _{x_road} can be expressed as the following equation (8).

The road surface shape calculation unit 525 calculates the road surface displacement amount _{x_road} based on the equation (8).

The preview distance calculation unit 526 _inputs the sensor distance _{z_ssr} , the sensor height change amount _{dH_ssr} calculated by the position change amount calculation unit 522 and / or the ground angle change amount _{dθ_ssr} , and inputs these values. based on the subject and previews position as controlled wheel of the detection (for example, front wheels) is for calculating a preview distance L _p between the road surface position currently ground when the sensor distance z _{_Ssr} was detected.

したがって、プレビュー距離L_pは、下記（１０）式のように表される。

プレビュー距離演算部５２６は、上記（１０）式に基づいて、プレビュー距離L_pを演算する。 FIG. 13 is a diagram illustrating the relationship between the ground angle _{θ_ssr} and the sensor distance _{z_ssr} . As can be seen from the figure, the preview distance L _p is defined as the _difference between the preview position R1 that is the detection target when the sensor distance _{z_ssr} is detected, and the vertical line extending vertically downward from the mounting position of the preview sensor 63 and the road surface. It is represented by the sum of the distance _{L_ssr} between the intersection R2 and the distance D between the intersection R2 and the ground contact point R3 of the wheel to be controlled (front wheel). The distance _{L_ssr} is expressed by the following equation (9).

Therefore, the preview distance L _p is expressed by the following equation (10).

The preview distance calculation unit 526 calculates the preview distance L _p based on the above equation (10).

Note that (10) As can be seen from the equation, the preview distance L sensor height change amount dH _{_Ssr} the calculation of _p is not used, the sensor distance z _{_Ssr} and ground angle variation d [theta] _{_Ssr} preview distance L _p on the basis of Is calculated. On the other hand, the preview distance L _p can also be calculated based on the sensor distance _{z_ssr} and the sensor height change amount _{dH_ssr} . In this case, the preview distance L _p is expressed by the following equation (11).

The data recording unit 527 repeatedly executes the data recording routine shown in FIG. When the data recording routine is started, the data recording unit 527, first in S200 of FIG. 15, it calculates the preview position D _p by adding the travel distance S and preview distance L _p of the vehicle. Since the vehicle travel distance S repeatedly fluctuates within the range of 0 to _{L p_max} as described above, the preview position D _p is within the range of L _{p to} L _p + L _{p_max} (the length represented by the maximum preview distance L _{p_max} It fluctuates repeatedly within the range. The process of S200 corresponds to the preview position calculation means of the present invention.

Next, the data recording unit 527 determines whether or not the preview position D _p is larger than the maximum preview distance L _{p_max} (S202). When the preview position D _p is less than or equal to the maximum preview distance L _{p_max} (S202: No), the preview position D _p is divided by a predetermined tire contact length _{L_tire} , and data is obtained by _rounding off the decimal point of the division result. The storage position i is calculated (S206). On the other hand, when the preview position D _p is larger than the maximum preview distance L _{p_max} (S202: Yes), the value _obtained by subtracting the maximum preview distance L _{p_max} from the preview position D _p is divided by the tire contact length _{L_tire} , The data storage position i is calculated by rounding off the decimal part (S204). Here, the tire contact length _{L_tire} is the length along the vehicle traveling direction of the portion where the tire portion of the wheel traveling at the preview position is in contact with the road surface, and is measured in advance by experiments or the like. The tire contact length _{L_tire} is set to about 0.1 m, for example.

The process of S206 from S202, the storage position i is obtained based on the preview position D _p. The storage position i is an address indicating a location where the road surface displacement amount _{x_road at} the preview position D _p used when calculating the storage position i is stored in the storage area 541 of the RAM 54. For example, when S = 0.2 m, L _p = 1.4 m, L _{p_max} = 2.0 m, and L _{_tire} = 0.1 m, the calculation result of the preview position D _{p in} S200 is 1.6 m, and this calculation result The determination result of S202 received is No, and in response to this determination result, the storage position i is calculated in S206. In this case, a calculation result of storage position i = 16 is derived. For example, when S = 1.1 m, L _p = 1.4 m, L _{p_max} = 2.0 m, and L _{_tire} = 0.1 m, the calculation result of the preview position D _{p in} S200 is 2.5 m. Upon receiving the calculation result, the determination result in S202 is Yes, and in response to this determination result, the storage position i is calculated in S204. In this case, the storage position i = 5 is obtained by dividing the value (= 0.5 m) obtained by subtracting L _{p_max} (= 2.0 m) from D _p (= 2.5 m) by _{L_tire} (= 0.1 m). The operation result is derived.

FIG. 18 is a diagram illustrating a correspondence relationship between the preview position _Dp and the storage position i. According to this figure, when the preview position D _p has a size within the range from the preview distance L _p to the maximum preview distance L _{p_max} , the storage position i representing the size corresponding to the preview position D _p is calculated. The On the other hand, when the preview position D _p has a size within the range to a value obtained by adding the preview distance L _p to a maximum preview distance L _{P_MAX} from the maximum preview distance L _{P_MAX} is the range of the range of 0 to preview distance L _p And the storage position i representing the size corresponding to the value after the shift is calculated. Therefore storage position i increases with the increase from 0 to _L p_max / L _tire preview position D _p in the range of up to an integer value, stored position when the preview position exceeds the maximum preview distance L _{P_MAX} i Returns to 0. Then, the storage position i is increased according to the increase of the preview again position D _p from it. That is, the minimum value of the storage position i is 0 and the maximum value is approximately L _{p_max} / _{L_tire} , and the storage position i repeatedly fluctuates (increases) within these ranges according to the preview position D _p .

Thus, the storage position i to be calculated on the basis of the preview position D _p, a constant relationship between the computed storage location i and the preview position D _p occurs. Therefore, as will be described later, the road surface displacement amount _{x_road} can be read out in the correct order based on this relationship. Further, the number of storage locations for storing the road surface displacement amount _{x_road} is sufficient if it represents the maximum value of the storage location i. Specifically, in the present embodiment, the number of memory locations of a road surface displacement x _{_Road} is an integer _L p_max / L _tire. The processing of S202 to S206 corresponds to the storage position calculation means of the present invention.

After calculating the storage location i in S204 or S206, the data recording unit 527 calculates the current location storage location j by dividing the vehicle travel distance S by the tire ground contact length _{L_tire} and _rounding off the decimal point in S208. Calculate. The current location storage position j represents a location where the road surface displacement amount of the road surface position where the vehicle is currently traveling is stored in the storage area 541 of the RAM 54.

Thereafter, in S210, it is determined whether the current location storage position j is equal to the previous storage position tmpj. The previous storage location tmpj is the storage location that was the current location storage location j when this routine was executed last time. That is, in S210, it is determined whether or not the storage location that was the current location storage location when this routine was executed last time is equal to the storage location that is the current location storage location when this routine is executed. If the current location storage position j and the previous storage position tmpj are not equal (S210: No), the process proceeds to S212, and the road surface displacement amount data _{tmp_x_road} [tmpj] stored in the previous storage position tmpj is deleted. In other words, if the road surface displacement data stored at the current location storage position when this routine was executed last time is already past data when this routine is executed this time, the past data will be Not necessary for control. Therefore, the data is erased and the storage location is made empty. The processes of S210 and S212 correspond to control information erasing means.

On the other hand, when the current location storage position j is equal to the previous storage position tmpj (S210: Yes), the process of S212 is skipped and the process proceeds to S214. Then, it is determined at S214, whether the data _{tmp_x} _road stored in the storage locations i [i] is cleared, that is whether the memory location i is empty. If the storage position i is empty (S214: Yes), the process proceeds to S216, in the storage location represented by the stored position i, the road shape calculating section 525 road displacement at the preview position D _p which is calculated by x _{_road} is recorded as record data tmp_x _{_road} [i].

On the other hand, if the storage position i is not empty (S214: No), the process proceeds to S218. In the situation where the determination result in S214 is No, that is, the situation where data is already recorded in the storage position i, the preview position has once retracted due to the pitch motion of the vehicle, the sampling time is short, or the vehicle is running This may occur when the distance traveled by the vehicle between the previous execution of this routine and the current execution of this routine is less than or equal to the tire ground contact length _{L_tire} because the speed V is small. In this case, the road surface displacement amount recorded at the storage position i when this routine was executed last time and the road surface displacement amount to be recorded when this routine is executed this time should be used effectively. Thus, the data recording unit 527, at S218, already recorded the displayed data _{tmp_x} _road [i] between the current calculated average value of the road surface displacement _{x _road ((tmp_x _road [i} ] + x _road) / 2 the)), as recording data _{tmp_x} _road [i], and records in the storage location represented by the storage locations i. The processing of S214 to S218 corresponds to the control information recording means of the present invention.

Thereafter, the data recording unit 527 proceeds to S220, substitutes the current location storage position j for the previous storage location tmpj, and ends this routine once. As can be seen from the above, the data recording unit 527, a preview position D _p based on the value obtained by dividing the tire contact length L _{_Tire,} a storage position is calculated i for road displacement x _{_Road} at the preview position D _p, The road surface displacement amount _{x_road} is recorded in the storage location represented by the storage position i thus calculated. The storage area 541 of this for RAM 54, the preview position D _p is each time advanced by the tire contact length _L _tire, road displacement x _{_Road} is recorded.

The preview compensation distance calculation unit 524 repeatedly executes the preview compensation distance calculation routine shown in FIG. When preview compensation distance calculating routine is started, preview compensating distance calculator 524, first at S300, by multiplying the preview compensation time T _p to the running speed V of the vehicle, calculates a preview compensation distance L _c. The preview compensation time T _p is a time set in advance as a control delay time for compensating for the operating time and communication time of the actuator 30 and the delay due to the internal filter. Therefore, the preview compensation distance L _c represents the distance traveled by the vehicle during the control delay time (preview compensation time T _p ).

Next, the preview compensation distance calculation unit 524 calculates the current location storage position j by dividing the vehicle travel distance S by the tire ground contact length _{L_tire} and _rounding down the decimal part (S302). Subsequently, the variable c is set to 0, and the maximum preview compensation distance L _{c_max} is _set to the maximum preview distance L _{p_max} (S304).

Thereafter, the preview compensation distance calculation unit 524 determines whether or not the road surface displacement amount data _{tmp_x_road} [c] recorded in the storage location represented by the data storage position c of the storage area 541 of the RAM 54 has been deleted, that is, It is determined whether or not the storage position c is empty (S306). If the storage position c is not empty (S306: No), the variable c is incremented (S314), and the incremented variable c _{divides the} maximum preview distance L _{p_max} by the tire ground contact length _{L_tire} and _rounds off the decimal part. It is determined whether the value is larger than the maximum value of the storage position (S316). When the variable c is equal to or less than the maximum value of the storage position (S316: No), the process returns to S306. On the other hand, when the variable c exceeds the maximum value of the storage position (S316: Yes), the process proceeds to S318.

If it is determined in S306 that the storage position c is empty (S306: Yes), the process proceeds to S308. The variable c when the determination result of S306 is Yes indicates the smallest storage position among the storage positions that represent the storage places that have been made free. In S308, the preview compensation distance calculation unit 524 determines whether or not the variable c is larger than the current location storage position j (S308). If the variable c is larger than the current position storage position j (S308: Yes), by multiplying the tire contact length L _{_Tire} the difference (c-j) between the variables c and the current location storage location j, the maximum preview compensation distance L _{c_max} Is calculated (S310). On the other hand, if the variable c is equal to or less than the current location storage location j (S308: No), since the maximum preview distance L _{P_MAX,} multiplied by the tire contact length L _{_Tire} the difference between the current location storage position j and the variable c (j-c) The maximum preview compensation distance L _{c_max} is calculated by subtracting the obtained value.

FIG. 19 is a diagram _{showing the} maximum preview compensation distance L _{c —} max calculated as described above as a virtual distance on the storage area 541 of the RAM 54. In the figure, each storage location in the storage area 541 is displayed by one grid. The number on each cell is a memory position that represents the memory location. Further, when road surface displacement amount data is recorded at a storage location, hatched lines are drawn on the cells representing the storage location. When the storage location is empty, it is not shaded. In the figure, the current location storage position is represented by j, and the smallest storage location among the storage locations representing the empty storage locations is represented by c. This c is the same value as the variable c used for the determination when the determination result in S306 of the preview compensation distance calculation routine is Yes.

FIG. _19A shows an example in which the maximum preview compensation distance L _{c_max} calculated in S310 is shown as a virtual distance on the storage area 541 when the determination result in S308 is Yes (c> j). As can be seen from the figure, the area in which the road surface displacement data is recorded is a continuous area represented by the storage position 0 to the storage position 14. No data is recorded in the area from the storage position 15 to the storage position 19. In addition, since the storage location 0 corresponds to the current location storage location j, data is recorded in the storage area 541 in 15 (c−j) storage locations that are continuous from the current location storage location j (storage location 0). Will be. Because each memory location is the preview position D _p data is recorded each time the advances by the tire contact length L _{_Tire,} by representing the length of each memory location in the tire contact length L _{_Tire,} the storage area 541, the vehicle It can be seen that the road surface displacement data on the road surface ahead is stored by the distance represented by the length (c−j) times the tire contact length _{L_tire} . In other words, the road surface displacement data ahead is not stored in the storage area 541. Accordingly, as shown in S310, the maximum preview compensation distance L _{c_max} , which is the maximum distance by which the control information (road surface displacement amount) can be compensated in view of the storage amount, is _represented by (c−j) and the tire contact length _{L_tire} . It is represented by the product of

FIG. 19B shows an example in which the maximum preview compensation distance L _{c_max} calculated in S312 is shown as a virtual distance on the storage area 541 when the determination result in S308 is No (c <j). As can be seen from the figure, the area in which the road surface displacement data is recorded includes a continuous area represented by storage position 0 to storage position 4 and a continuous area represented by storage position 9 to storage position 19. It is divided into two. No data is recorded in the area from storage position 5 to storage position 8. Since the data is recorded at the storage position 0 after the data is recorded at the storage position 19, the storage area 541 has 16 consecutive storage locations from the current location storage position j (storage position 9) to the storage position 4. It can be seen that data is recorded in Therefore, it can be seen that the storage area 541 stores from the current value of the vehicle to road surface displacement data on the road surface ahead by a distance represented by a length 16 times the tire ground contact length _{L_tire} . This magnification (16 times) is obtained by subtracting (j−c) from the total number of storage locations (= L _p — _max / L — _tire ). Therefore, as shown in S312, the maximum preview compensation distance L _{c_max} is represented by a value obtained by subtracting the product of the tire contact length _{L_tire} and (j−c) from the maximum preview distance L _{p_max} . Note that if the determination result in S316 is Yes, there is no erased data among the road surface displacement data recorded in the storage area 541, that is, there is no empty storage location. The preview compensation distance L _{c_max} is set to the maximum preview distance L _{p_max} . The processes of S306 to S316 correspond to the maximum preview compensation distance calculation means.

After setting the maximum preview compensation distance L _{c_max in S306} to _S316 , the preview compensation distance calculation unit 524 determines whether the preview compensation distance L _c is larger than the maximum preview compensation distance L _{c_max} in S318. . When the preview compensation distance L _c is larger than the maximum preview compensation distance L _{c_max} (S318: Yes), the preview compensation distance L _c is set to the maximum preview compensation distance L _{c_max} (S320). As a result, the preview compensation distance _Lc is restricted to the upper limit (upper limit guard). The process of S320 corresponds to preview compensation distance upper limit guard means. Thereafter, this routine is terminated. On the other hand, when the preview compensation distance L _c is _{equal to} or less than the maximum preview compensation distance L _{c_max} (S318: No), the upper limit of the preview compensation distance is not required, so that the process of S320 is skipped and the routine ends.

Data reading unit 528 repeatedly executes the data reading routine shown in FIG. When data reading routine is started, the data reading unit 528, first, in S400, by adding the travel distance S and preview compensating distance L _c of the vehicle, calculates the preview compensation position D _c. The preview compensation position D _c represents the position of the road surface on which the vehicle travels when the preview compensation time T _p has elapsed. The process of S400 corresponds to the preview compensation position calculation means of the present invention.

Next, the data reading unit 528 determines whether or not the preview compensation position D _c is greater than the maximum preview distance L _{p_max} (S402). When the preview compensation position D _c is equal to or _smaller than the maximum preview distance L _{p_max} (S402: No), the readout position n is calculated by dividing the preview compensation position D _c by the tire ground contact length _{L_tire} and _rounding down the decimal point ( S404). On the other hand, when the preview compensation position D _c is larger than the maximum preview distance L _{p_max} (S402: Yes), the value _obtained by subtracting the maximum preview distance L _{p_max} from the preview compensation position D _c is divided by the tire contact length _{L_tire} and the decimal point is obtained. Is read out to calculate the reading position n (S406). The read position n calculated in S404 or S406 is the position where the vehicle travels after the preview compensation time T _p (control delay time) has elapsed, of the road surface displacement amount recorded in the storage area 541 of the RAM 54, that is, the preview compensation position. This represents a place where the road surface displacement amount at the preview position corresponding to D _c is stored. The processing of S404 and S406 corresponds to the reading position calculation means of the present invention. In addition, since the preview compensation position D _c is not affected by the pitch motion of the vehicle, the preview compensation position D _c has a length represented by the preview maximum distance L _{p_max} even when such a motion occurs. Increases repeatedly within the range. Thus, the read position is calculated based on such preview compensation position D _c also repeats increased within the maximum value of the memory location from 0.

Then, the data reading unit 528, by adding the 1/2 of the tire contact length L _{_Tire} to a value obtained by multiplying the tire contact length L _{_Tire} on the calculated read position n, calculates the preview compensation position threshold TMPD _c (S408). Here, the preview compensation position threshold value tmpD _c will be described. FIG. 20 is a diagram showing the preview compensation position threshold value tmpD _c as a virtual distance on the storage area 541 of the RAM 54. Since the reading position n is an integer value obtained by dividing the preview compensation position D _c by the tire contact length _{L_tire} , the preview compensation position D _c is a value _obtained by multiplying the storage position (n−1) by the tire contact length _{L_tire.} And a value _obtained by multiplying the read position n by the tire contact length _{L_tire} . The preview compensation position threshold value tmpD _c (= n * _{L_tire} + _{L_tire} / 2) is the median value of the preview compensation position D _c estimated as described above.

If the preview compensation position D _c is smaller than the preview compensation position threshold value tmpD _c , the true preview compensation position D _c is stored with the preview position having the road surface displacement amount recorded at the storage location represented by the readout position n, and There is a high possibility that the position is between the preview position having the road surface displacement amount recorded in the storage location represented by the position (n−1). Therefore, true preview compensation is performed by using the road surface displacement amount recorded at the memory location represented by the read position n and the road surface displacement amount recorded at the memory location represented by the memory location (n−1). A more correct road surface displacement amount at the position D _c can be calculated.

When the preview compensation position D _c is larger than the preview compensation position threshold tmpD _c , the true preview compensation position D _c is a preview position having a road surface displacement amount recorded at the storage location represented by the readout position n. There is a high possibility that the position is between the preview position having the road surface displacement amount recorded at the storage location represented by the storage location (n + 1). Therefore, the true preview compensation position D is obtained by using the road surface displacement amount recorded at the storage location represented by the read position n and the road surface displacement amount recorded at the storage location represented by the storage location (n + 1). More correct road surface displacement in _c can be calculated.

Based on the above, in the present embodiment, at S410, it determines whether the Preview compensation position Dc is smaller than the preview compensation position threshold TMPD _c. When the preview compensation position Dc is smaller than the preview compensation position threshold value tmpD _c (S410: Yes), the road surface displacement amount data _{tmp_x_road} [n] recorded in the storage location represented by the readout position n is obtained in S412. The road surface displacement amount at the preview compensation position D _c is calculated using the road surface displacement amount data _{tmp_x_road} [n−1] recorded at the storage location represented by the storage position (n−1). Specifically, as shown in the following equation (12), a corrected road surface displacement amount _{x_road_c} linearly interpolated by _{tmp_x_road} [n] and _{tmp_x_road} [n-1] is calculated.

On the other hand, when the preview compensation position D _c is larger than the preview compensation position threshold value tmpD _c (S410: No), the road surface displacement amount data _{tmp_x_road} [recorded at the storage location represented by the read position n in S414] The road surface displacement amount at the preview compensation position D _c is calculated using the road surface displacement amount data _{tmp_x_road} [n + 1] recorded at the storage location represented by n] and the recording position (n + 1). Specifically, as shown in the following equation (13), the corrected road surface displacement amount _{x_road_c} linearly interpolated by _{tmp_x_road} [n] and _{tmp_x_road} [n + 1] is calculated.

FIG. 21 is a diagram _comparing the road surface displacement amount _{x_road} recorded in each storage location of the storage area 541, the corrected road surface displacement amount _{x_road_c} calculated in S412 or S414, and the actual road surface displacement. In the figure, the corrected road surface displacement amount _{x_road_c} is represented by a thick line, the road surface displacement amount _{x_road} recorded in the storage area 541 is represented by a thin line, and the actual road surface displacement is represented by a dotted line. The numbers in the figure represent the storage positions of the road surface displacement amounts recorded in the storage area 541. As can be seen from the figure, the road surface displacement amount x _{_road} recorded at each storage location changes in a stepwise manner, while the corrected road surface displacement amount x _{_road_c} is the road surface displacement amount x _recorded at the adjacent storage location. _{Changes smoothly} by interpolating with _{_road} . A depression is formed in the actual road surface corresponding to the portion represented by the storage position 6. However, since the size of the recess is less than the tire contact length _{L_tire} and the wheel gets over the recess, the wheel is not affected by the recess.

After calculating the corrected road surface displacement amount _{x_road_c} as described above, the data reading unit 528 once ends this routine.

The target control force calculation unit 529 inputs the corrected road surface displacement amount _{x_road_c} calculated by the data reading unit 528. Then, a target control force F to be output by the actuator 30 is calculated by multiplying the input corrected road surface displacement amount _{x_road_c} by a predetermined gain. The predetermined gain value is a value calculated in advance so that, for example, when the vehicle gets over the corrected road surface displacement amount _{x_road_c} , the on-spring transmission rate of the road surface input becomes small. Then, each switching element is controlled so that the switching element of the drive circuit 70 opens and closes at a duty ratio corresponding to the calculated target control force F or a deviation between the target control force F and the control force output from the actuator 30. Output a signal. Thereby, each switching element opens and closes according to the designated duty ratio, and the operation of the actuator 30 is controlled by such duty control. The operation of the actuator 30 controlled in this way is completed after the preview compensation time T _{p has} elapsed. Controlled wheel just the vehicle during operation completion (eg front wheels) is, through the preview position D _p that corresponds to the modified road displacement _x _road_c. In this way, preview control is performed at an optimal timing.

22 (a) to 22 (h) are views showing a state in which road surface displacement data is recorded in the storage area 541 of the RAM 54 by the above-described preview control, together with the traveling state of the vehicle. In the figure, the storage area 541 has a storage location for storing 20 pieces of data. The storage position representing each storage location increases in order from the right. That is, the storage position representing the rightmost storage location is the smallest storage location (i = 0), and the storage location representing the leftmost storage location of the storage area 541 is the largest storage location (i = 19). The maximum preview distance L _{p_max} is 2.0 m, and the tire contact length _{L_tire} is 0.1 m.

FIG. 22A shows a recorded state of the road surface displacement when the travel distance S is 0 m. At this time, the preview position D _p obtained by adding the preview distance L _p and the travel distance S is 1.65 m. The road surface displacement amount at the preview position is recorded in the storage location represented by the storage position 16 in the storage area 541.

FIG. 22B shows a recorded state of the road surface displacement when the vehicle travel distance S is 0.25 m. As can be seen from the figure, at this point of time, the front wheel of the vehicle is fitted in the recess, so that a pitch motion is generated such that the front sinks. Thus, the sensor height and ground angle greatly changes, resulting preview position D _p is retracted to 1.55 m. The road surface displacement amount at the preview position is recorded in the storage location represented by the storage position 15 in the storage area 541. Further, when road surface displacement amounts are stored in the storage positions (storage position 0 and storage position 1) representing the already traveled position, those road surface displacement amounts are deleted. In the figure, the storage location represented by the symbol c is the storage location from which the road surface displacement amount has been deleted.

FIG. 22C shows a recorded state of the road surface displacement when the vehicle travel distance S is 0.45 m. At this time the preview position D _p is 1.95 m. The road surface displacement at the preview position is recorded in the storage location represented by the storage position 19. Further, since the preview position D _p in a state that is shown in FIG. 22 (b) is retracted once, while the vehicle from FIG 22 (b) to FIG. 22 (c) proceeds, the preview position D _p The road surface displacement amount at a position near 1.65 m may be calculated again. In this case, the recalculated road surface displacement amount and the average value of the road surface displacement amount already recorded in the storage location represented by the storage position 16 are calculated, and the calculated average value is represented by the storage location 16. Is recorded in the memory location.

FIG. 22D shows a recorded state of the road surface displacement when the vehicle travel distance S is 0.65 m. At this time, the value obtained by adding the preview distance L _p and the travel distance S is 2.1 m, which exceeds the maximum preview distance L _{p_max} . Therefore, a value (0.1 m) obtained by subtracting the maximum preview distance L _{p — max} (2.0 m) from the added value (2.1 m) is calculated as the preview position D _p . The road surface displacement at the preview position is recorded in the storage location represented by the storage position 1.

FIG. 22E shows a recorded state of the road surface displacement when the vehicle travel distance S is 1.3 m. At this time, the sum of the preview distance L _p and the travel distance S is 2.65 m, which exceeds the maximum preview distance L _{p_max} . Therefore, a value (0.65 m) obtained by subtracting the maximum preview distance L _{p_max} (2.0 m) from the added value (2.65 m) is calculated as the preview position D _p . The road surface displacement at the preview position is recorded in the storage location represented by the storage position 6.

FIG. 22 (f) shows a recorded state of the road surface displacement when the vehicle travel distance S is 1.95 m. At this time, a value obtained by adding the preview distance L _p and the travel distance S is 3.05 (m), which exceeds the maximum preview distance L _{p_max} . Therefore, a value (1.05 m) obtained by subtracting the maximum preview distance L _p — _max (= 2.0 m) from the added value (3.05 m) is calculated as the preview position D _p . The road surface displacement amount at the preview position is recorded in the storage location represented by the storage position 10. Further, as can be seen from the figure, in the storage area 541, the road surface displacement amount is recorded in the continuous storage area from the storage position 0 to the storage position 10 and the storage position 19, and the continuous storage from the storage position 11 to the storage position 18. The road surface displacement amount is not recorded in the storage area. Since the storage position 19 is a storage position representing the current location of the vehicle, the tire contact length _{L_tire} (0.1 m) is _added to the number of storage locations (12) where road surface displacement is stored continuously from the storage position 19. The distance (1.2 m) multiplied by is set as the maximum preview compensation distance L _{c —} max. Therefore, when the calculated preview compensation distance L _c exceeds 1.2 m, the preview compensation distance L _c is restricted to 1.2 m.

FIG. 22G shows a recorded state of the road surface displacement amount when the vehicle travel distance S is 2.15 m. As can be seen from the figure, since the travel distance S (2.15 m) exceeds the maximum preview distance L _{p_max} in this situation, a value obtained by subtracting the maximum preview distance L _{p_max} (2.0 m) from the travel distance S (0) .15 m) is set as the travel distance S. Also, the preview position D _p is 1.75 m. Therefore, the road surface displacement amount at the preview position is stored in the storage location represented by the storage position 17. Data is recorded in continuous storage areas from storage position 1 to storage position 17, and no data is recorded in storage positions 18, 19, 0. Since the storage position 1 is a storage position representing the current location of the vehicle, the tire contact length _{L_tire} (0.1 m) is _added to the number of storage locations (17) where road surface displacement is recorded continuously from the storage position 1. The distance (1.7 m) multiplied by is set as the maximum preview compensation distance L _{c —} max. Therefore, when the calculated preview compensation distance L _c exceeds 1.7 m, the preview compensation distance L _c is restricted to 1.7 m.

FIG. 22 (h) shows the recorded state of the road surface displacement when the vehicle travel distance S is 0.95 (m). At this time, the sum of the preview distance L _p and the travel distance S is 2.75 m, which exceeds the maximum preview distance L _{p_max} . Therefore, a value (0.75 m) _obtained by subtracting the maximum preview distance L _{p_max} from the added value is calculated as the preview position D _p . The road surface displacement amount at the preview position is recorded in the storage location represented by the storage position 7. Further, as can be seen from the figure, in the storage area 541, road surface displacement is recorded in a continuous storage area from the storage position 0 to the storage position 7 and a continuous storage area from the storage position 9 to the storage position 19. At position 8, the amount of road surface displacement is not recorded. Since the storage position 9 is a storage position representing the current location of the vehicle, the tire ground contact length _{L_tire} (0.1 m) is _added to the number of storage locations (19) where the road surface displacement amount is stored continuously from the storage position 9. The distance (1.9 m) multiplied by is set as the maximum preview compensation distance L _{c —} max. Therefore, when the calculated preview compensation distance L _c exceeds 1.9 m, the preview compensation distance L _c is restricted to 1.9 m.

  Although the reading position is not shown in FIG. 22, the reading position repeatedly increases within the range from 0 to the maximum value of the storage position as described above. That is, the road surface displacement amount is read in the order of the storage positions. Since the order of the storage positions represents the order of the preview positions, the road surface displacement amount is read in the order of the preview positions. For this reason, for example, after the road surface displacement amount at the preview position 1.65 m is recorded in the storage position 16 as shown in FIG. 22A, a pitch motion occurs, and the preview as shown in FIG. Even when the position is retreated to 1.55 m and the road surface displacement amount at that position is recorded in the storage position 15, the road surface displacement amount on the side where the preview position is smaller is read out first. That is, the road surface displacement amount at the storage position 15 recorded later is read out first, and the road surface displacement amount at the storage position 16 recorded earlier is read out later. Thus, the road surface displacement amount is read in the order of the preview position, so that the order in which the wheels pass the road surface (the road surface passage order) matches the reading order of the road surface displacement amount at the road surface position. Therefore, it is possible to suppress the deterioration of the control performance of the preview control due to the mismatch between the road surface passing order and the reading order.

As described above, according to the present embodiment, based on the preview position D _p representing the target road surface position of the detection when the sensor distance z _{_Ssr} is detected by preview sensor 63, at the preview position D _p A storage position i for storing the road surface displacement amount _{x_road} is calculated. Then, the road surface displacement amount _{x_road} is recorded in the storage location represented by the calculated storage location i in the storage area 541 of the RAM 54 having a plurality of storage locations. Therefore, even when the preview position D _p is changed by the posture change such as the pitch motion of the vehicle, a road surface displacement x _{_Road} in a storage position in light of the change is recorded. Thus even when the preview position D _p is retracted, on the basis of the calculated memory location in light of the preview position D _p, a road surface displacement x _{_Road} in order from the side (side preview position is small) close to the vehicle Can be read. Thereby, deterioration of the control performance of the preview control can be suppressed.

FIG. 23 is a graph showing the required time resolution of road surface displacement data recorded in the storage area 541 of the RAM 54. Here, the required time resolution is the time interval required from the time when a certain road surface displacement data is recorded until the next data is recorded. The smaller the required time resolution, the more precisely the road surface displacement data. Will be recorded. In FIG. 23, the horizontal axis represents the traveling speed V of the vehicle, and the vertical axis represents the necessary time resolution. Further, the graph indicated by the symbol A is a graph showing the change of the necessary time resolution with respect to the traveling speed V when the preview control shown in the present embodiment is performed. The graph indicated by the symbol B is a graph showing a change in the required time resolution with respect to the traveling speed V when the preview control shown in Patent Document 2 is performed. FIG. 24 shows the preview control sampling time T _s represented by the graph B, the number of road surface displacement data stored in each speed range, and the preview control according to the present embodiment represented by the graph A. 5 is a diagram comparing the number of road surface displacement data stored in FIG.

  As can be seen from FIG. 24, in the case of the conventional method, each speed region of the low speed region (20 to 60 km / h), the medium speed region (60 to 130 km / h), and the high speed region (130 to 250 km / h). The sampling time is fixed. When recording data at every sampling time, the time resolution is equal to the sampling time. Further, when comparing the sampling times of the respective speed regions, the sampling time is shorter as the speed is higher. Therefore, the required time resolution when the preview control is executed by the conventional method decreases stepwise as the traveling speed increases, as shown in the graph B of FIG. When the required time resolution changes stepwise in this way, the required time resolution at a speed near the boundary of the change increases. For example, in graph B, the required time resolution near a traveling speed of 50 km / h is 12 ms, and the vehicle travels about 0.17 m during 12 ms. Since 0.17 m is longer than the tire ground contact length of a general vehicle, it cannot cover the amount of road surface displacement that is originally required for control. Therefore, it is not possible to ensure appropriate accuracy of control based on the road surface displacement amount.

On the other hand, since the preview control of the present embodiment records data (road surface displacement amount) every time the vehicle advances by the tire contact length _{L_tire} , the required time resolution is obtained by dividing the tire contact length _{L_tire} by the traveling speed. Become. Therefore, the required time resolution is inversely proportional to the traveling speed as shown in graph A of FIG. By defining the storage resolution (required time resolution) of data (road surface displacement amount) by the tire ground contact length as in this embodiment, the road surface displacement amount recording interval is set to the tire ground contact even when the traveling speed V is large or small. _Becomes long _{L_tire} . Therefore, data can always be recorded with an optimum roughness.

  Further, as can be seen from FIG. 24, in the conventional method, a dedicated storage area is required for each speed area, so that a storage area for storing 55 data in total is required. In the present embodiment, it is only necessary to have a common storage area for all speeds, and therefore, for example, a storage area sufficient to store 20 pieces of data is sufficient. As described above, the storage area can be saved by executing the preview control of the present embodiment.

Further, according to this embodiment, ground angle of the preview sensor 63, since the preview sensor 63 such that an acute angle as viewed from the vehicle side is attached to the vehicle, it is possible to extend the preview distance L _p. For this reason, the margin time can be made longer than the control delay time (preview compensation time T _p ) even when the vehicle traveling speed V is high.

Further, the data reading unit 528, the calculated storage location in the data recording unit 527 based on the preview position D _p that corresponds to the preview compensation position D _c is computed as the read position n. Then, the target control force F of the actuator 30 is calculated by the target control force calculation unit 529 based on the road surface displacement stored in the storage location represented by the calculated read position n. Based on the target control force F calculated in this way, the operation of the actuator 30 is controlled. In this way, by compensating for the delay in preview control on a position basis, the operation of the actuator 30 can be completed at an appropriate timing.

Further, by calculating the storage position i based on the preview position D _p to a value obtained by dividing the tire contact length L _{_Tire,} each time the preview position D _p is changed by the tire contact length L _{_Tire} min, the preview position D _p The road surface displacement amount _{x_road at} is stored. That is, the road surface interval where the road surface displacement amount _{x_road} is recorded is the tire contact length _{L_tire} . When the road surface interval in which the road surface displacement amount _{x_road} is recorded is shorter than the tire contact length, there arises a problem that the storage capacity of the storage area increases. Further, since the road surface change in the section shorter than the tire contact length _{L_tire} may be ignored when the tire gets over the change as shown in FIG. 21, the road surface change in such a minute section. There is little need to remember. On the other hand, when the road surface interval in which the road surface displacement amount _{x_road} is recorded is longer than the tire ground contact length _{L_tire} , the information on the road surface displacement amount is insufficient and the riding comfort deteriorates. For these reasons, the road surface interval where the road surface displacement amount is recorded as in the present embodiment is the tire ground contact length _{L_tire} , so that an increase in storage capacity can be suppressed, and an optimal distance interval without excess or deficiency. _Can store the road surface displacement amount _{x_road} .

Further, since the vehicle travel distance S is calculated so as to repeatedly vary within a range not _exceeding the maximum preview distance L _{p_max} , the preview position D calculated based on the vehicle travel distance S and the preview distance L _{p p} also fluctuates repeatedly within the range of the length represented by the maximum preview distance L _{p_max} , and the storage position i calculated based on the preview position D _p also fluctuates repeatedly within the range corresponding to the maximum preview distance L _{p_max.} To do. By repeatedly changing the storage position i, the storage location of the storage area 541 is repeatedly used. Thereby, a large amount of control information can be recorded with a small recording capacity.

  Moreover, the road surface displacement memorize | stored in the memory | storage location showing the road surface already drive | worked among the road surface displacement memorize | stored in the memory area 541 of RAM54 is erase | eliminated. As a result, a new road surface displacement can be recorded at the storage location represented by the storage location that has become free.

As mentioned above, although embodiment of this invention was described, this invention should not be limited to the said embodiment. For example, in the above-described embodiment, the example in which the preview control of the present invention is applied when the control force (driving force) generated by the actuator of the suspension is obtained has been described. That is, in the above-described embodiment, the example in which the preview control of the present invention is applied to the operation control of the actuator that operates the wheel to be controlled has been shown. However, the present invention can be applied not only to the operation control of the actuator that actively moves the wheel to be controlled, but also to the operation control of the actuator that is used to control the operation of the wheel to be controlled. For example, in a suspension including a shock absorber that generates a damping force, the actuator changes the damping force characteristic of the shock absorber, whereby the vertical movement (vertical vibration) of the wheel by an external input is controlled. The preview control of the present invention can also be applied to such actuator operation control. In this case, as shown in FIG. 25, the CPU 52 has a target damping force calculation unit 529 instead of the target control force calculation unit. The target damping force calculation unit 529 receives the corrected road surface displacement amount _{x_road_c} output from the data reading unit 528, and calculates the target damping force F to be generated by the shock absorber based on the corrected road surface displacement amount _{x_road_c} . Then, a control signal is output to an actuator that controls the damping force characteristics of the shock absorber so that the calculated target damping force F is generated.

Further, the present invention can be applied not only to an actuator that controls the vertical movement of a wheel, but also to an actuator that controls the rotational movement of a wheel. For example, in a vehicle that travels by rotating each wheel with an actuator built in each wheel, the present invention can also be applied when controlling the driving force and braking force of the actuator. In this case, as shown in FIG. 26, the CPU 52 has a target driving force calculation unit (or target braking force calculation unit) 529. The target driving force calculation unit 529 receives the corrected road surface displacement amount _{x_road_c} output from the data reading unit 528, and the target driving force (or target braking force) to be generated by the actuator based on the corrected road surface displacement amount _{x_road_c.} Calculate F. Then, a control signal is output to the actuator so that the calculated target driving force (or target braking force) F is generated.

In the above-described embodiment, an example in which the road surface displacement amount is calculated as the control information has been shown. Any information that is necessary for control may be used. For example, when controlling the actuator of the active suspension as in this embodiment, the road surface gradient at the preview position may be calculated instead of the road surface displacement at the preview position. The target control force that is finally output by the actuator may be used as control information. In this case, as shown in FIG. 27, the target control force calculation unit 529 calculates the target control force F based on the road surface displacement amount _{x_road} calculated by the road surface shape calculation unit 525. The data recording unit 527, based on the preview position D _p, calculates the storage position i representing the storage location of the calculated target control force F based on the road surface displacement x _{_Road} at the preview position D _p. Then, the target control force F is recorded in the storage location represented by the calculated storage position i. During the data read, the target control force F recorded in the read position n which is calculated on the basis of the preview compensation position D _c is output.

In the above embodiment, when it is determined in the road surface shape calculation routine (FIG. 15) that data has already been recorded at the storage position i (S214: No), the road surface displacement amount _{x_road} calculated this time. When already recorded an average value of the data _{tmp_x} _road recorded [i] in the memory location i in the storage position i (S218) has shown an example already recorded the displayed data and the current computed road surface displacement The larger one (maximum value) of the quantity may be recorded in the storage position. In this case, as shown in FIG. 28, when it is determined that data has already been recorded at the storage position i (S214: No), the road surface displacement amount _{x_road} calculated this time is stored at the storage position i in S218. recorded data _{tmp_x} _road to greater or not than the [i] is determined, when large recording the road surface displacement x _{_Road} in the storage position i, otherwise already recorded data _{tmp_x} _road [i ] May be left in the memory position i as it is.

_Further, the sampling time (sampling period) T _s of the sensor distance _{z_ssr} can be freely set within a range in which road surface displacement can be recorded at least for each tire contact length _{L_tire} . Thus, the present invention can be modified without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 10 ... Suspension main body, 20 ... Coil spring, 30 ... Actuator, 31 ... Electric motor, 35 ... Ball screw mechanism, 50 ... Suspension ECU, 51 ... Input interface, 52 ... CPU, 521 ... State quantity calculating part, 522 ... Position change amount Calculation unit 523 ... Travel distance calculation unit 524 ... Preview compensation distance calculation unit 525 ... Road surface shape calculation unit 526 ... Preview distance calculation unit 527 ... Data recording unit 528 ... Data reading unit 529 ... Target control force calculation 53, ROM, 54, RAM, 541, storage area, 55, output interface, 56, bidirectional bus, 61, sprung acceleration sensor, 62, vehicle speed sensor, 63, preview sensor, 70, drive circuit, _Dc ... preview compensation position, D _p ... preview _position, L _tire ... tire contact length, L _c ... Purebi Over compensation distance, L _{c_max} ... maximum preview compensation distance, L _p ... preview distance, L _{P_MAX} ... maximum preview distance, TMPD _c ... preview compensation position threshold, T _p ... preview compensation time, T _s ... sampling _time, x _road ... road Displacement amount, x _{_road_c} … corrected road surface displacement amount, z _{_ssr} … sensor distance

Claims (4)

A preview sensor that is attached to the vehicle and detects a distance from the attachment position to a road surface position where the vehicle is scheduled to travel for each preset sampling time, based on the distance detected by the preview sensor, In an actuator operation control device that controls the operation of an actuator for controlling the operation of a wheel that travels in a preview position, which is a road surface position that is a detection target when the distance is detected,
A travel distance calculating means for calculating the travel distance of the vehicle based on the travel speed of the vehicle;
Based on the distance detected by the preview sensor, the preview position that is the detection target when the distance is detected and the control target wheel that is a wheel that is scheduled to travel in the preview position are currently grounded. Preview distance calculating means for calculating a preview distance that is a distance between the road surface position and
Preview position calculation means for calculating the preview position based on a value obtained by adding the preview distance to the travel distance of the vehicle;
Based on the distance detected by the preview sensor, for controlling the operation of the wheel to be controlled when the wheel to be controlled travels the preview position that is detected when the distance is detected. Control information calculating means for calculating control information which is information necessary for controlling the operation of the actuator;
A memory having a plurality of storage locations for storing the control information calculated by the control information calculation means;
Based on the preview position calculated by the preview position calculation means, information necessary for controlling the operation of an actuator that controls the operation of the wheel to be controlled when the wheel to be controlled travels at the preview position. Storage position calculation means for calculating a storage position representing a storage location in the memory of the control information calculated by the control information calculation means;
Control information recording means for recording the control information in a storage location represented by a storage position calculated by the storage position calculation means among the storage locations in the memory;
An actuator operation control device comprising: The actuator operation control device according to claim 1,
A preview compensation distance, which is a distance traveled by the vehicle during the preview compensation time, is calculated by multiplying the traveling speed of the vehicle by a preview compensation time set in advance as a delay time related to the control of the actuator operation. Preview compensation distance calculating means for
Preview compensation position calculation means for calculating a preview compensation position representing a position of a road surface on which the vehicle travels after the preview compensation time has elapsed, based on a value obtained by adding the preview compensation distance to the travel distance of the vehicle;
Read position calculation means for calculating a storage position calculated based on the preview position corresponding to the preview compensation position by the storage position calculation means as a read position;
A control amount for controlling the operation of the actuator is calculated based on the control information recorded in the storage location represented by the read position calculated by the read position calculation means among the storage locations in the memory. Control amount calculation means for
An actuator operation control device, further comprising: In the actuator operation control device according to claim 1 or 2,
The storage position calculation means calculates the storage position based on the preview position and a tire ground contact length that is a length along a vehicle traveling direction of a portion where the control target wheel is in contact with a traveling road surface. An actuator operation control device. The actuator operation control device according to any one of claims 1 to 3,
The travel distance calculating means is configured to travel the vehicle based on the travel speed of the vehicle and the maximum preview distance so that the travel distance of the vehicle repeatedly varies within a range not exceeding a preset maximum preview distance. An operation control device for an actuator, characterized in that

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