JP2011178227A - Control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for a vehicle, capable of changing a turning characteristic according to a turning stage of the vehicle. <P>SOLUTION: When it is determined that a second condition is satisfied by a second condition determination means based on a time differential value of a steering angle and it is determined that a first condition is satisfied by a first condition determination means based on the steering angle, a camber angle adjusting device is operated to adjust a camber angle of at least a turning outer wheel of wheels to a first camber angle. In this case, whether or not the vehicle is in the turning state can be detected by acquiring the steering angle and the time differential value of the steering angle is steering angular velocity, and the steering angle and the time differential value of the steering angle directly reflect an operation of turning of a driver and reflect a turning stage of the vehicle based on an operation of the driver. Thus, the camber angle of the wheel is adjusted based on the two conditions of the first condition and the second condition, and thereby the turning characteristic of the vehicle can be changed according to the turning stage. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a vehicle control device used in a vehicle including a camber angle adjusting device for adjusting a camber angle of a wheel, and more particularly to a vehicle control device capable of changing a turning characteristic according to a turning stage of the vehicle. Is.

  2. Description of the Related Art Conventionally, there has been known a technique for ensuring traveling stability of a vehicle by adjusting a camber angle of a wheel according to the traveling state of the vehicle. With regard to this type of technology, for example, Patent Document 1 discloses a technology that improves the vehicle's limit travel performance by applying a negative camber to the wheel when the vehicle travels at a predetermined speed or higher.

JP-A-60-193781

  Here, when the vehicle turns, different turning characteristics are required depending on the turning stage. That is, it is required that the steering response is good from the initial stage to the middle stage of the turn (around the peak of the steering angle from the start of the turn), and stable at the final stage of the turn (when the steering angle approaches 0). Therefore, it is required that the direction of the vehicle be directed quickly in the direction of travel straight after turning.

  However, in the technology disclosed in Patent Document 1, a negative camber is applied based on the speed of the vehicle regardless of whether or not the vehicle is in a turning state, so that the turning characteristics of the vehicle are changed according to the turning stage. There was a problem that the required turning performance could not be obtained.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a vehicle control device that can change the turning characteristics of a vehicle according to the turning stage.

Means for Solving the Problems and Effects of the Invention

  In order to achieve this object, according to the vehicle control device of the first aspect, the second condition determination means determines that the second condition based on the time differential value of the steering angle is satisfied, and the first condition determination When it is determined by the means that the first condition based on the steering angle is satisfied, the camber angle adjusting device is operated by the first camber angle adjusting means so that at least the camber angle of the turning outer wheel of the wheels becomes the first camber angle. Adjusted. Here, it is possible to detect whether the vehicle is turning by acquiring the steering angle. In addition, since the time differential value (steering angular velocity) of the steering angle directly reflects the operation related to the turning of the driver, the steering angle and the time differential value of the steering angle are determined based on the driver's operation. It reflects the turning stage. As described above, the camber angle of the wheel is adjusted based on the two conditions of the first condition and the second condition that directly depend on the operation of the driver, thereby changing the turning characteristic of the vehicle according to the turning stage. There is an effect that can.

  According to the vehicle control device of the second aspect, since the first camber angle is an angle different from a predetermined angle of the camber angle when the vehicle travels straight, the camber angle of the wheel is adjusted by the first camber angle adjusting means. The size and direction of the canvas last generated by adjusting the can be made different from the size and direction of the canvas last generated on the wheels when the vehicle travels straight ahead. Thereby, in addition to the effect which the control apparatus for vehicles of Claim 1 shows, there exists an effect which can improve driving | running | working stability when a vehicle turns by the canvas last produced in the vehicle width direction of a vehicle.

  According to the vehicle control device of the third aspect, when the first camber angle adjusting means satisfies the first condition by the first condition determining means and then satisfies the second condition by the second condition determining means. When the determination is made, the camber angle of the wheel is adjusted to the first camber angle. Therefore, in addition to the effect exhibited by the vehicle control device according to claim 1 or 2, the wheel camber angle is arbitrarily determined without being influenced by the driver's habit. It is possible to adjust the camber angle of the wheel at the turning stage, and there is an effect that the reliability can be improved.

  In other words, the second condition determining means makes a determination based on the time differential value (steering angular velocity) of the steering angle, and some of the drivers are hesitant that the steering angular velocity is abnormally fast. If the determination by the means precedes the determination by the first condition determination means, the camber angle may be adjusted by a driver other than the set turning stage. On the other hand, since the steering angle directly reflects that the vehicle is in a turning state, the turning stage set by setting the judgment by the first condition judging means ahead of the judgment by the second condition judging means. It is possible to prevent the camber angle from being adjusted except for.

  According to the vehicle control device of the fourth aspect, the second condition except that the first condition determining means determines that the first condition is satisfied and the second condition determining means determines that the second condition is satisfied. The camber angle adjusting device is actuated by the camber angle adjusting means to adjust the camber angle to a second camber angle that is the same as the camber angle when the vehicle travels straight ahead or closer to the second camber angle than the first camber angle. Therefore, in addition to the effect produced by the vehicle control device according to any one of claims 1 to 3, an effect of suppressing the canvas last generated on the wheel by adjusting to the second camber angle and improving the steering response. There is.

  According to the vehicle control device of the fifth aspect, the first condition determining means performs the first operation until it is determined that the absolute value of the steering angle is not less than the first threshold value and not more than the second threshold value. Since it is determined that the condition is satisfied, it is determined that the first condition is satisfied until it is determined that the turning radius of the vehicle is small and the steering angle is greater than or equal to the first threshold value and then becomes smaller than the second threshold value. On the other hand, since the second condition determining means determines that the second condition is satisfied when it is determined that the time differential value of the absolute value of the steering angle is equal to or less than a predetermined negative value, the steering angle is set to 0. When returning, it is determined that the second condition is satisfied. Therefore, it is the final stage of the turn that satisfies both the first condition and the second condition.

  Here, in the final stage of turning, it is required that the direction of the vehicle be directed to the traveling direction of straight advance after turning, and the camber angle of the wheel is adjusted to the first camber angle. In addition to the effects of the vehicle control device described in any of the above, the vehicle can be in a stable understeering tendency at the final stage of turning, improving the running stability of the vehicle and moving the vehicle in the straight traveling direction. There is an effect that can be directed quickly.

  According to the vehicle control device of the sixth aspect, since the camber angle adjusting device is disposed on the rear wheel of the wheel, and the first camber angle adjusting means adjusts the camber angle of the rear wheel. In addition to the effect produced by the vehicle control device according to any one of the items 5, there is an effect that the device configuration of the vehicle can be simplified.

  According to the vehicle control device of the seventh aspect, the first camber angle is an angle changed from a predetermined angle of the camber angle when the vehicle travels straight ahead in the negative direction. By adjusting the camber angle of the wheel to the first camber angle, the canvas last in the turning center direction can be generated in the turning outer wheel. Thereby, in addition to the effect which the vehicle control apparatus in any one of Claim 1 to 6 shows, there exists an effect which can prevent that the vehicle front side swells outside the turning circle at the time of turning.

It is the schematic diagram which showed typically the vehicle by which the vehicle control apparatus in 1st Embodiment of this invention is mounted. It is a front view of a suspension apparatus. It is the block diagram which showed the electric constitution of the control apparatus for vehicles. It is a flowchart which shows a camber control process. (A) is a schematic diagram which shows the relationship between the time of a vehicle, and the absolute value of a steering angle, (b) is a schematic diagram which shows the relationship between time and the time differential value of the absolute value of a steering angle, (c ) Is a schematic diagram showing the relationship between time and camber angle. It is the schematic diagram which showed typically the vehicle by which the vehicle control apparatus in 2nd Embodiment is mounted. It is a front view of a suspension apparatus. It is the block diagram which showed the electric constitution of the control apparatus for vehicles. It is a flowchart which shows a camber control process.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram schematically showing a vehicle 1 on which a vehicle control device 100 according to the first embodiment of the present invention is mounted. Note that arrows UD, LR, and FB in FIG. 1 indicate the up-down direction, the left-right direction, and the front-rear direction of the vehicle 1, respectively.

  First, a schematic configuration of the vehicle 1 will be described. As shown in FIG. 1, the vehicle 1 includes a vehicle body frame BF, a plurality of (four wheels in the present embodiment) wheels 2 that support the vehicle body frame BF, and some of the plurality of wheels 2 (the book In the present embodiment, the wheel drive device 3 that rotationally drives the left and right front wheels 2FL, 2FR) and a part of the plurality of wheels 2 (in this embodiment, the left and right rear wheels 2RL, 2RR) are connected to the body frame BF. A plurality of suspension devices 4 that are suspended on the vehicle frame, a plurality of suspension devices 40 that suspends a part of the plurality of wheels 2 (in this embodiment, the left and right front wheels 2FL, 2FR) on the vehicle body frame BF, and a plurality of wheels 2 Among them, the steering device 5 is mainly configured to steer a part (in this embodiment, the left and right front wheels 2FL, 2FR).

  Next, the detailed configuration of each part will be described. As shown in FIG. 1, the wheel 2 includes left and right front wheels 2FL and 2FR located on the front side (arrow F direction side) of the vehicle 1 and left and right rear wheels located on the rear side (arrow B direction side) of the vehicle 1. Wheels 2RL and 2RR are provided. In the present embodiment, the left and right front wheels 2FL and 2FR are configured as driving wheels that are rotationally driven by the wheel driving device 3. In the wheel 2, the left and right front wheels 2FL, 2FR and the left and right rear wheels 2RL, 2RR are all configured to have the same shape, outer diameter, and characteristics. Note that a shaft (axle) that rotatably supports the left and right rear wheels 2RL and 2RR on the vehicle body frame BF and a wheel drive device that drives the rear wheels 2RL and 2RR are not shown.

  As described above, the wheel drive device 3 is a device for rotationally driving the left and right front wheels 2FL and 2FR, and is configured by an electric motor 3a as described later (see FIG. 3). As shown in FIG. 1, the electric motor 3a is connected to the left and right front wheels 2FL and 2FR via a differential gear (not shown) and a pair of drive shafts 31 (axles).

  When the driver operates the accelerator pedal 61, a rotational driving force is applied to the left and right front wheels 2FL, 2FR from the wheel drive device 3, and the left and right front wheels 2FL, 2FR rotate according to the operation amount of the accelerator pedal 61. Driven. The difference in rotation between the left and right front wheels 2FL and 2FR is absorbed by the differential gear.

  The suspension devices 4 and 40 function as a so-called suspension for mitigating vibration transmitted from the road surface to the vehicle body frame BF via the wheels 2, and are configured to be extendable and retractable as shown in FIG. The device 4 is provided on the left and right rear wheels 2RL and 2RR, and the suspension device 40 is provided on the left and right front wheels 2FL and 2FR, respectively. Further, the suspension device 4 in the present embodiment also has a function as a camber angle adjusting mechanism for adjusting the camber angle of the wheel 2.

  Here, with reference to FIG. 2, the detailed structure of the suspension apparatus 4 is demonstrated. FIG. 2 is a front view of the suspension device 4. Here, only the configuration that functions as a camber angle adjusting mechanism will be described, and the configuration that functions as a suspension is the same as a known configuration, and thus description thereof is omitted. Further, since the configuration of each suspension device 4 is common to the left and right rear wheels 2RL and 2RR, the suspension device 4 corresponding to the right rear wheel 2RR is shown in FIG. 2 as a representative example. However, in FIG. 2, illustration of the drive shaft 31 and the like is omitted for easy understanding.

  As shown in FIG. 2, the suspension device 4 transmits a knuckle 43 supported by the vehicle body frame BF via a strut 41 and a lower arm 42, an RR motor 44RR that generates a driving force, and a driving force of the RR motor 44RR. The worm wheel 45 and the arm 46 are configured to mainly include a movable plate 47 that is swingably driven with respect to the knuckle 43 by the driving force of the RR motor 44RR transmitted from the worm wheel 45 and the arm 46. .

  The knuckle 43 supports the wheel 2 so as to be steerable. As shown in FIG. 2, the upper end (upper side in FIG. 2) is connected to the strut 41, and the lower end (lower side in FIG. 2) is connected via a ball joint. Are coupled to the lower arm 42. The RR motor 44RR applies a driving force for swing driving to the movable plate 47, is constituted by a DC motor, and has a worm (not shown) formed on its output shaft 44a. The worm wheel 45 transmits the driving force of the RR motor 44RR to the arm 46, meshes with a worm formed on the output shaft 44a of the RR motor 44RR, and constitutes a staggered shaft gear pair together with the worm.

  The arm 46 transmits the driving force of the RR motor 44RR transmitted from the worm wheel 45 to the movable plate 47, and has one end (right side in FIG. 2) via the first connecting shaft 48 as shown in FIG. The other end (left side in FIG. 2) is connected to the upper end (upper side in FIG. 2) via the second connection shaft 49 while being connected to a position eccentric from the rotation shaft 45 a of the worm wheel 45. The movable plate 47 supports the wheel 2 in a rotatable manner. As described above, the upper end (upper side in FIG. 2) is coupled to the arm 46, and the lower end (lower side in FIG. 2) is interposed via the camber shaft 50. The knuckle 43 is pivotally supported so as to be swingable.

  According to the suspension device 4 configured as described above, when the RR motor 44RR is driven, the worm wheel 45 rotates and the rotational motion of the worm wheel 45 is converted into linear motion of the arm 46. As a result, when the arm 46 moves linearly, the movable plate 47 is driven to swing with the camber shaft 50 as the swing shaft, and the camber angle of the wheel 2 is adjusted.

  In the present embodiment, the first connecting shaft 48, the rotating shaft 45a, the rotating shaft 45a of each connecting shaft 48, 49 and the worm wheel 45 in the direction from the vehicle body frame BF toward the wheel 2 (arrow R direction). A first camber state positioned in a straight line in the order of the second connecting shaft 49, and a second camber state positioned in a straight line in the order of the rotating shaft 45a, the first connecting shaft 48, and the second connecting shaft 49 (see FIG. 2), the camber angle of the wheel 2 is adjusted so that one of the camber states is established.

  Thereby, in the state where the camber angle of the wheel 2 is adjusted to the first camber state or the second camber state, even if an external force is applied to the wheel 2, no force in the direction of rotating the arm 46 is generated. A camber angle of 2 can be maintained. Further, in the present embodiment, in the first camber state, the camber angle of the wheel 2 is adjusted to a predetermined minus angle (in this embodiment, −4.5 °, hereinafter referred to as “first camber angle”). Then, a negative camber is applied to the wheel 2. On the other hand, in the second camber state (the state shown in FIG. 2), the camber angle of the wheel 2 has a smaller absolute value than the first camber angle, and a predetermined angle in the positive direction from the first camber angle (−1 in the present embodiment). .5 °, hereinafter referred to as “second camber angle”).

  The suspension device 40 is omitted in the function of adjusting the camber angles of the left and right front wheels 2FL, 2FR (that is, in the suspension device 4 shown in FIG. 2, the extension / retraction function by the RR motor 44RR is omitted). Except for (), the other configuration is the same as that of the suspension device 4, and the description thereof is omitted. That is, the camber angles of the rear wheels 2RL and 2RR can be adjusted to the first camber angle or the second camber angle, but the front wheels 2FL and 2FR cannot be adjusted.

  Returning to FIG. The steering device 5 is a device for steering an operation of the steering 63 by the driver to the left and right front wheels 2FL, 2FR, and is configured as a so-called rack and pinion type steering gear. According to the steering device 5, the operation (rotation) of the steering 63 by the driver is first transmitted to the universal joint 52 via the steering column 51, and the pinion 53 a of the steering box 53 is changed while the angle is changed by the universal joint 52. Is transmitted as rotational motion. Then, the rotational motion transmitted to the pinion 53a is converted into a linear motion of the rack 53b, and the tie rod 54 connected to both ends of the rack 53b moves by the linear motion of the rack 53b. As a result, the tie rod 54 pushes and pulls the knuckle 55, so that a predetermined rudder angle is given to the front wheels 2FL, 2FR (wheel 2).

  The accelerator pedal 61 and the brake pedal 62 are operation members operated by the driver, and the traveling speed and braking force of the vehicle 1 are determined according to the operation state (depression amount, depressing speed, etc.) of the pedals 61 and 62. The wheel drive device 3 is driven and controlled. The steering 63 is an operation member operated by the driver, and the left and right front wheels 2FL and 2FR are steered by the steering device 5 according to the operation state (steer angle, steer angular velocity, etc.).

  The vehicle control device 100 is a device for controlling each part of the vehicle 1 configured as described above. For example, the camber angle adjusting device 44 (see FIG. 3).

  Next, a detailed configuration of the vehicle control device 100 will be described with reference to FIG. FIG. 3 is a block diagram showing an electrical configuration of the vehicle control device 100. As shown in FIG. 3, the vehicle control device 100 includes a CPU 71, a ROM 72, and a RAM 73, which are connected to an input / output port 75 via a bus line 74. The input / output port 75 is connected to a device such as the wheel drive device 3.

  The CPU 71 is an arithmetic unit that controls each unit connected by the bus line 74, and the ROM 72 is a control program executed by the CPU 71 (for example, the program of the flowchart shown in FIG. 4) or fixed value data (see FIG. 5). This is a non-rewritable non-volatile memory for storing T1, T2, T3) and the like shown in the figure.

  The RAM 73 is a memory for storing various data in a rewritable manner when executing the control program, and as shown in FIG. 3, a camber flag 73a and a turning flag 73b are provided. The camber flag 73a is a flag indicating whether or not the camber angle of the wheel 2 is adjusted to the first camber angle, and the CPU 71 displays the camber angle of the wheel 2 when the camber flag 73a is on. Is determined to have been adjusted to the first camber angle. The turning flag 73b is a flag indicating whether or not a first condition to be described later is satisfied. The CPU 71 determines that the first condition is satisfied when the turning flag 73b is on.

  As described above, the wheel drive device 3 is a device for rotationally driving the left and right front wheels 2FL, 2FR (see FIG. 1), and an electric motor 3a that applies a rotational driving force to the left and right front wheels 2FL, 2FR. A drive control circuit (not shown) for driving and controlling the electric motor 3a based on an instruction from the CPU 71 is mainly provided. However, the wheel drive device 3 is not limited to the electric motor 3a, and other drive sources can naturally be adopted. Examples of other drive sources include a hydraulic motor and an engine.

  The camber angle adjusting device 44 is a device for adjusting the camber angle of each wheel 2, and as described above, the driving force for swinging is applied to the movable plate 47 (see FIG. 2) of each suspension device 4, respectively. A total of two RL motors to be provided, RR motors 44RL and 44RR, and a drive control circuit (not shown) for driving and controlling each of the motors 44RL and 44RR based on an instruction from the CPU 71 are mainly provided.

  The acceleration sensor device 81 is a device for detecting the acceleration of the vehicle 1 and outputting the detection result to the CPU 71. The acceleration sensor device 81a includes a longitudinal acceleration sensor 81a, a lateral acceleration sensor 81b, and the acceleration sensors 81a and 81b. It mainly includes an output circuit (not shown) that processes the detection result and outputs it to the CPU 71.

  The longitudinal acceleration sensor 81a is a sensor that detects the acceleration in the longitudinal direction (arrow FB direction in FIG. 1) of the vehicle 1 (body frame BF), so-called longitudinal G, and the lateral acceleration sensor 81b is the vehicle 1 (vehicle body). This is a sensor that detects the acceleration in the left-right direction (the direction of arrow LR in FIG. 1) of the frame BF, that is, the so-called lateral G. In the present embodiment, each of these acceleration sensors 81a and 81b is configured as a piezoelectric sensor using a piezoelectric element.

  Further, the CPU 71 time-integrates the detection results (front and rear G, lateral G) of the respective acceleration sensors 81a and 81b input from the acceleration sensor device 81 to calculate the speeds in two directions (front and rear directions and left and right directions), respectively. At the same time, the traveling speed of the vehicle 1 can be acquired by synthesizing these two-direction components.

  The accelerator pedal sensor device 61a is a device for detecting the operation amount of the accelerator pedal 61 and outputting the detection result to the CPU 71. An angle sensor (not shown) for detecting the depression amount of the accelerator pedal 61; It mainly includes an output circuit (not shown) that processes the detection result of the angle sensor and outputs it to the CPU 71.

  The brake pedal sensor device 62a is a device for detecting the operation amount of the brake pedal 62 and outputting the detection result to the CPU 71. An angle sensor (not shown) for detecting the depression amount of the brake pedal 62; It mainly includes an output circuit (not shown) that processes the detection result of the angle sensor and outputs it to the CPU 71.

  The steering sensor device 63a is a device for detecting a rotation angle (steering angle θ) of a steering shaft (not shown) and outputting the detection result to the CPU 71, and an angle sensor (not shown) for detecting the rotation angle of the steering shaft. And an output circuit (not shown) that processes the detection result of the angle sensor and outputs the result to the CPU 71.

  In the present embodiment, each angle sensor is configured as a contact-type potentiometer using electric resistance. Further, the CPU 71 time-differentiates the detection result (operation amount) of each angle sensor input from each sensor device 61a, 62a, 63a, and the time of the absolute value of the depression speed of each pedal 61, 62 and the steering angle θ. The differential value (d | θ | / dt) can be acquired. It is also possible to acquire the rotation direction (steering direction) of the steering shaft.

  Examples of the other input / output device 90 shown in FIG. 3 include a yaw rate sensor device and a roll angle sensor device. The yaw rate sensor device is a device for detecting the yaw rate of the vehicle 1 and outputting the detection result to the CPU 71, and the vehicle 1 around the vertical axis passing through the center of gravity of the vehicle 1 (arrow UD direction axis in FIG. 1). A yaw rate sensor that detects the rotational angular velocity of the (body frame BF) and an output circuit that processes the detection result of the yaw rate sensor and outputs the result to the CPU 71 are mainly provided. The roll angle sensor device is a device for detecting the roll angle of the vehicle 1 and outputting the detection result to the CPU 71. A roll angle sensor that detects the rotation angle of the vehicle 1 (body frame BF) and an output circuit that processes the detection result of the roll angle sensor and outputs the result to the CPU 71 are mainly provided.

  As another input / output device 90, for example, the current position of the vehicle 1 is acquired using GPS, and the acquired current position of the vehicle 1 is acquired in association with map data in which information on roads is stored. A navigation device and the like are also exemplified.

  Next, camber control processing will be described with reference to FIGS. 4 and 5. FIG. 4 is a flowchart showing camber control processing. This process is a process that is repeatedly executed by the CPU 71 (for example, at intervals of 0.2 seconds) while the power of the vehicle control device 100 is turned on, and each wheel 2 (left and right rear wheels 2RL, 2RR). This is a process for adjusting the camber angle. FIG. 5A is a schematic diagram showing the relationship between the time t of the vehicle 1 and the absolute value (| θ |) of the steering angle, and FIG. 5B is the time of time t and the absolute value of the steering angle. FIG. 5 is a schematic diagram showing the relationship between the differential value (d | θ | / dt), and FIG. 5C is a schematic diagram showing the relationship between the time t and the camber angle.

  The CPU 71 obtains the steering angle θ based on the output signal of the steering sensor device 63a regarding the camber control process shown in FIG. 4 (S1). Next, the CPU 71 determines whether or not the absolute value (| θ |) of the steering angle θ is equal to or greater than the first threshold value T1 (see FIG. 5A) (S2). As a result, when it is determined that the absolute value (| θ |) of the steering angle is equal to or greater than the first threshold value T1 (S2: Yes), the turning flag 73b indicating that the first condition is satisfied is turned on ( The process proceeds to S3) and S4.

  On the other hand, if it is determined that the absolute value of the steering angle is smaller than the first threshold T1 as a result of the process of S2 (S2: No), the first condition is not satisfied, so the process skips to the process of S4. . In the process of S4, it is determined whether or not the turning flag 73b is on. If it is determined that the turning flag 73b is off (S4: No), the first condition is not satisfied, and the camber control process is terminated.

  On the other hand, if it is determined as a result of the process of S4 that the turning flag 73b is on (S4: Yes), then the absolute value (| θ |) of the steering angle, which is the extinction condition of the first condition, is It is determined whether or not it is equal to or less than a second threshold value T2 (see FIG. 5A) (S5). When it is determined that the absolute value (| θ |) of the steering angle is larger than the second threshold value T2 (S5: No), it indicates that the first condition has not disappeared (the vehicle 1 is turning). Therefore, the time differential value (d | θ | / dt) of the absolute value of the steering angle, which is a condition for establishing the second condition, is equal to or less than the negative predetermined value T3 (see FIG. 5B). Whether or not (S6). When it is determined that the time differential value (d | θ | / dt) of the absolute value of the steering angle is larger than the negative predetermined value T3 (S6: No), whether the steering angle is not returned to the 0 direction, This indicates that the steering angular velocity returning to the 0 direction is slow, and it is not necessary to adjust the camber angle of the wheel 2, and thus this camber control process is terminated.

  On the other hand, if it is determined that the time differential value (d | θ | / dt) of the absolute value of the steering angle is equal to or less than the predetermined negative value T3 as a result of the process of S6, the second condition is also satisfied. In this case, the steering angle is returned to the zero direction at a steering angular velocity equal to or greater than the predetermined value T3, indicating that it is necessary to prepare for straight travel at the end of the turn, so the camber angle of the wheel 2 is set to the first angle. It is necessary to adjust the camber angle. Next, the CPU 71 determines whether or not the camber flag 73a is on (S7). If it is determined that the camber flag 73a is on (S7: Yes), the camber angle of the wheel 2 has already been adjusted to the first camber angle (a negative camber is assigned), so this camber control is performed. End the process.

  On the other hand, if it is determined that the camber flag 73a is OFF as a result of the process of S7 (S7: No), the camber angle adjusting device 44 is activated to camber the wheels 2 (left and right rear wheels 2RL, 2RR). The angle is adjusted to the first camber angle (S8) (see FIG. 5C), the camber flag 73a is turned on (S9), and this camber control process is terminated.

  Further, if it is determined that the absolute value (| θ |) of the steering angle is equal to or smaller than the second threshold value T2 as a result of the process of S5 (S5: Yes), it indicates that the first condition has disappeared. Therefore, the turning flag is turned off (S10), and then the camber angle adjusting device 44 is operated to adjust the camber angle of the wheel 2 (left and right rear wheels 2RL, 2RR) to the second camber angle (S11) (FIG. 5). (See (c)), the camber flag 73a is turned off (S12), and the camber control process is terminated.

  According to the first embodiment described above, the camber angle adjusting device 44 is operated when the second condition based on the time differential value of the steering angle is satisfied and the first condition based on the steering angle is satisfied. The camber angle of the wheel 2 is adjusted to the first camber angle. Here, since the steering angle can detect whether the vehicle 1 is in a turning state, and the time differential value of the steering angle is the steering angular velocity, both directly reflect the operation related to the turning of the driver. It reflects the turning stage of the vehicle 1 based on the driver's operation. From the above, the turning characteristic of the vehicle 1 can be changed according to the turning stage by adjusting the camber angle of the wheel 2 based on the two conditions of the first condition and the second condition.

  In addition, when the second condition is satisfied after the first condition is satisfied, the camber angle of the wheel 2 is adjusted to the first camber angle. The camber angle of the wheel 2 can be adjusted. That is, some drivers have a habit of abnormally high steering angular velocity, so the second condition may be satisfied regardless of the turning state. Therefore, if the camber angle is adjusted to the first camber angle when the first condition is met after the second condition is met, the camber angle is set to the first camber angle other than the set turning stage depending on the driver. The camber angle may be adjusted. On the other hand, since the steering angle directly reflects that the vehicle 1 is in a turning state, the steering angle is set on the condition that the second condition is satisfied after the first condition is satisfied. The camber angle can be prevented from being adjusted outside the turning stage, and the reliability can be improved.

  Further, except that the first condition is satisfied and the second condition is satisfied, the camber angle adjusting device 44 is operated to adjust the camber angle of the wheel 2 to the second camber angle having an absolute value smaller than the first camber angle. Therefore, canvas rust generated on the wheel 2 can be suppressed, and the steering response can be improved.

  The first condition is established when it is determined that the absolute value of the steering angle is equal to or greater than the first threshold value, and disappears when it is determined that the absolute value of the steering angle is equal to or less than the second threshold value. Therefore, it is established when the turning radius of the vehicle 1 is smaller than the predetermined radius. On the other hand, the second condition is satisfied when it is determined that the time differential value of the absolute value of the steering angle is equal to or less than a predetermined negative value. This corresponds to when the steering angle is returned to zero. Therefore, both the first condition and the second condition are satisfied at the final stage of turning. In the final stage of turning, when the vehicle 1 is required to be directed quickly in the direction of straight travel after turning, the camber angle of the wheel 2 (rear wheels 2RL, 2RR) is adjusted to the first camber angle and negative. Since the camber is applied, the vehicle 1 can be made to have a stable understeer tendency, the running stability of the vehicle 1 can be improved, and the vehicle 1 can be directed quickly in the straight traveling direction.

  Further, as a criterion for determining whether or not the second condition is satisfied, whether the time differential value of the absolute value of the steering angle is equal to or less than a predetermined negative value is used, as shown in FIG. It is possible to easily determine whether the turning starts when the absolute value increases or the turning end when the absolute value of the steering angle decreases, and the camber angle of the wheel 2 at the end of turning can be reliably adjusted to the first camber angle. .

  Further, since the process of S5 is performed after the processes of S2 and S4, even if the second condition is satisfied, if the first condition disappears, the camber angle of the wheel 2 is adjusted to the second camber angle. Therefore, the camber angle of the wheel 2 is adjusted to the second camber angle when the steering angle approaches 0 (by turning the turn). Accordingly, when the turn with the steering angle within the predetermined range is completed, the camber angle of the wheel 2 can be reliably adjusted to the second camber angle.

  In the flowchart (camber control procedure) shown in FIG. 4, the processing of S1 is performed as the steering angle acquisition unit according to claim 1, the processing of S2 and S4 is performed as the first condition determination unit, and the second condition determination unit. Corresponds to the process of S6, and the first camber angle adjusting means corresponds to the process of S8. The second camber angle adjusting means described in claim 4 corresponds to the process of S11.

  Next, a second embodiment will be described with reference to FIGS. In 1st Embodiment, although the vehicle 1 which is the control object of the vehicle control apparatus 100 demonstrated the case where the camber angle of right-and-left rear wheel 2RL and 2RR was comprised by the camber angle adjustment apparatus 44, it comprised. The vehicle 201 in the second embodiment is configured such that the camber angles of the left and right front wheels 2FL, 2FR can be adjusted by the camber angle adjusting device 44, and the camber angles are not adjusted for the left and right rear wheels 2RL, 2RR. ing.

  In the first embodiment, the case where the left and right rear wheels 2RL and 2RR are adjusted to the first camber angle (−4.5 °) for the vehicle 1 that is the control target of the vehicle control device 100 has been described. In the second embodiment, a case will be described in which the turning outer wheel of the left and right front wheels 2FL, 2FR is adjusted to the first camber angle (+ 2.5 ° in the present embodiment). In addition, the same code | symbol is attached | subjected about the part same as 1st Embodiment, and the description is abbreviate | omitted.

  FIG. 6 is a schematic diagram schematically showing a vehicle 201 on which the vehicle control device 200 according to the second embodiment is mounted. Note that arrows UD, LR, and FB in FIG. 6 indicate the up-down direction, the left-right direction, and the front-rear direction of the vehicle 201, respectively.

  First, a schematic configuration of the vehicle 201 will be described. As shown in FIG. 6, the vehicle 201 includes a plurality of (four wheels in the present embodiment) wheels 2. In the present embodiment, the left and right front wheels 2FL, 2FR are suspended from the vehicle body frame BF by the suspension device 204, while the left and right rear wheels 2RL, 2RR are suspended from the vehicle body frame BF by the suspension device 40. Note that the suspension device 40 has a function of adjusting the camber angles of the left and right rear wheels 2RL, 2RR (that is, the extension / contraction function by the RR motor 44RR is omitted in the suspension device 4 shown in FIG. 2). Except for (), the other configuration is the same as that of the suspension device 4, and the description thereof is omitted. In addition, the suspension device 204 in the present embodiment also has a function as a camber angle adjustment mechanism that adjusts the camber angle of the wheel 2.

  Here, with reference to FIG. 7, the detailed structure of the suspension apparatus 204 is demonstrated. FIG. 7 is a front view of the suspension device 204. Here, only the configuration that functions as a camber angle adjusting mechanism will be described, and the configuration that functions as a suspension is the same as a known configuration, and thus description thereof is omitted. Further, since the configuration of each suspension device 204 is common to the left and right front wheels 2FL and 2FR, the suspension device 204 corresponding to the right front wheel 2FR is illustrated in FIG. 7 as a representative example. However, in FIG. 7, illustration of the drive shaft 31 and the like is omitted for easy understanding.

  As shown in FIG. 7, the suspension device 204 transmits the knuckle 43 supported by the vehicle body frame BF via the strut 41 and the lower arm 42, the FR motor 44FR that generates a driving force, and the driving force of the FR motor 44FR. The worm wheel 45 and the arm 246, and the movable plate 47 that is swingably driven with respect to the knuckle 43 by the driving force of the FR motor 44FR transmitted from the worm wheel 45 and the arm 246 are mainly configured. .

  The arm 246 transmits the driving force of the FR motor 44FR transmitted from the worm wheel 45 to the movable plate 47, and one end (right side in FIG. 7) is connected via the first connecting shaft 248 as shown in FIG. The other end (left side in FIG. 7) is connected to the upper end (upper side in FIG. 7) via the second connection shaft 49 while being connected to a position eccentric from the rotation shaft 45 a of the worm wheel 45.

  According to the suspension device 204 configured as described above, when the FR motor 44FR is driven, the worm wheel 45 rotates and the rotational motion of the worm wheel 45 is converted into linear motion of the arm 246. As a result, when the arm 246 moves linearly, the movable plate 47 is driven to swing with the camber shaft 50 as the swing shaft, and the camber angle of the wheel 2 is adjusted.

  In the present embodiment, the connecting shafts 248, 49 and the rotating shaft 45a of the worm wheel 45 are in the direction from the vehicle body frame BF toward the wheel 2 (arrow R direction), the rotating shaft 45a, the first connecting shaft 248, A first camber state positioned in a straight line in the order of the second connecting shaft 49, and a second camber state positioned in a straight line in the order of the first connecting shaft 248, the rotating shaft 45a, and the second connecting shaft 49 (see FIG. 7), the camber angle of the wheel 2 is adjusted.

  Thereby, in the state in which the camber angle of the wheel 2 is adjusted to the first camber state or the second camber state, even if an external force is applied to the wheel 2, no force in the direction of rotating the arm 246 is generated. A camber angle of 2 can be maintained. In the present embodiment, in the first camber state, the camber angle of the wheel 2 is adjusted to a predetermined angle in the plus direction (in this embodiment, + 2.5 °, hereinafter referred to as “first camber angle”). The wheel 2 is given a positive camber. On the other hand, in the second camber state (the state shown in FIG. 7), the camber angle of the wheel 2 has a smaller absolute value than the first camber angle, and a predetermined angle in the negative direction from the first camber angle (−1 in the present embodiment). .5 °, hereinafter referred to as “second camber angle”).

  In the suspension device 40, the function of adjusting the camber angles of the left and right rear wheels 2RL, 2RR is omitted (that is, the extension / contraction function by the RR motor 44RR is omitted in the suspension device 4 shown in FIG. 2). Except for the point), the other configuration is the same as that of the suspension device 4, and the description thereof is omitted. That is, the camber angles of the front wheels 2FL and 2FR can be adjusted to the first camber angle or the second camber angle, but the rear wheels 2RL and 2RR cannot be adjusted.

  Next, with reference to FIG. 8, the vehicle control apparatus 200 mounted on the vehicle 201 will be described. The vehicle control device 200 is a device for controlling each part of the vehicle 201. For example, the vehicle control device 200 is an FL motor 44FL that is a part of the camber angle adjusting device 44 according to the operation state of the pedals 61 and 62 and the steering 63. , FR motor 44FR is controlled to operate.

  Next, camber control processing will be described with reference to FIG. FIG. 9 is a flowchart showing camber control processing. This process is a process that is repeatedly executed by the CPU 71 (for example, at intervals of 0.2 seconds) while the power source of the vehicle control device 200 is turned on, and for each wheel 2 (left and right front wheels 2FL, 2FR) This is a process for adjusting the camber angle. In the camber control process in the second embodiment described below, differences from the camber control process (see FIG. 4) in the first embodiment will be described.

  With respect to the camber control process shown in FIG. 9, the CPU 71 acquires the steering angle θ and the steering direction based on the output signal of the steering sensor device 63a (S21). If it is determined that the camber flag 73a is OFF as a result of the processing of S7 (S7: No), the camber angle adjusting device 44 is operated to turn the outer wheel of the wheel 2 (the left and right front wheels 2FL, 2FR). Is adjusted to the first camber angle (S22), the camber flag 73a is turned on (S9), and the camber control process is terminated. In the process of S22, it is determined which of the left and right front wheels 2FL, 2FR is a turning outer wheel based on the turning direction acquired in the process of S21, and the turning outer wheel of the left and right front wheels 2FL, 2FR is determined. The camber angle is adjusted to the first camber angle (positive camber).

  According to the second embodiment described above, the vehicle control device 200 adjusts the camber angle of the turning outer wheel of the left and right front wheels 2FL, 2FR to a positive camber, so that the canvas last generated in the turning outer wheel A moment opposite to the turning direction is generated in the front wheels 2FL and 2FR of the vehicle 201 to prevent the behavior of the vehicle 201 from becoming temporarily unstable at the end of turning, as in the first embodiment. The traveling stability of the vehicle can be improved, and the vehicle can be directed quickly in the traveling direction of straight travel after turning. In addition, the suspension device 204 is disposed on the front wheels 2FL and 2FR in the wheel 2 and the camber angle of the front wheels 2FL and 2FR is adjusted, so that the device configuration of the vehicle 201 can be simplified.

  In the flowchart shown in FIG. 9 (camber control treatment), the processing of S21 corresponds to the steering angle acquisition means according to claim 1, and the processing of S22 corresponds to the first camber angle adjustment means.

  The present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and various improvements and modifications can be made without departing from the spirit of the present invention. It can be easily guessed.

  The numerical values given in the above embodiments are merely examples, and other numerical values can naturally be adopted. For example, the values of the first camber angle and the second camber angle described in the above embodiments can be set arbitrarily.

  In each of the above-described embodiments, the case where the vehicles 1,201 to which the vehicle control devices 100, 200 are applied is the front wheel drive system, but is not limited thereto, and the rear wheel drive system vehicle is not limited thereto. It is also possible to apply to four-wheel drive type vehicles.

  In the first embodiment, the camber angles of the rear wheels 2RL and 2RR are adjusted. In the second embodiment, the camber angles of the front wheels 2FL and 2FR are adjusted. However, the present invention is not limited to these. In addition, it is possible to adjust the camber angles of the four wheels by providing each suspension device with a camber angle adjustment function.

  In the second embodiment, the case where the camber angles of the turning outer wheels of the front wheels 2FL and 2FR are adjusted has been described. However, the present invention is not necessarily limited to this. In the vehicle 1 capable of adjusting the angle, the camber angle of the turning outer wheel can be adjusted.

  In each of the above embodiments, the case where the second condition is satisfied when the time derivative of the absolute value of the steering angle is equal to or less than a predetermined negative value (T3 shown in FIG. 5B) has been described. It is not limited, and the sign of the predetermined value and the value can be arbitrarily set. In addition to T3, another predetermined value can be provided. Thereby, the turning stage where the second condition is satisfied can be arbitrarily set, the camber angle of the wheel 2 can be adjusted according to the turning stage of the vehicles 1 and 201, and the turning characteristic can be arbitrarily changed.

  In each of the above embodiments, the camber angle of the wheel 2 is adjusted to the first camber angle or the second camber angle by the camber angle adjusting device 44, and when the vehicle 1,201 travels straight, the wheel 2 is the second camber angle. The case where the camber angle is set has been described. That is, the case where the predetermined camber angle and the second camber angle when the vehicles 1 and 201 are traveling straight ahead has been described is not limited to this. When the suspension device and the camber angle adjusting device can adjust the camber angle of the wheel 2 to an arbitrary angle, the second camber angle adjusting means sets the camber angle (second camber angle) of the wheel 2 from the first camber angle. Can be adjusted to an angle close to a predetermined angle (a camber angle when the vehicle 1,201 travels straight). In this case, the predetermined camber angle when the vehicles 1,201 travel straight ahead and the second camber angle are not the same, but the camber angle of the wheel 2 is adjusted to the second camber angle, so that the canvas The steering response can be secured by reducing the last.

100,200 Vehicle control device 1,201 Vehicle 2 Wheel 2FL Left front wheel (part of the wheel)
2FR Right front wheel (part of the wheel)
2RL Left rear wheel (part of wheel)
2RR Right rear wheel (part of the wheel)
4,204 Suspension device 44 Camber angle adjustment device 44FL FL motor (part of camber angle adjustment device)
44FR FR motor (part of camber angle adjustment device)
44RL RL motor (part of camber angle adjustment device)
44RR RR motor (part of camber angle adjustment device)

Claims (7)

A vehicle control device used in a vehicle including a plurality of wheels and a camber angle adjusting device that adjusts a camber angle of at least some of the plurality of wheels,
Steering angle acquisition means for acquiring the steering angle of the vehicle;
First condition determining means for determining whether the steering angle acquired by the steering angle acquiring means is within a predetermined range that satisfies the first condition;
Second condition determination means for determining whether a time differential value of the steering angle acquired by the steering angle acquisition means satisfies a predetermined second condition;
When the second condition determining means determines that the second condition is satisfied and the first condition determining means determines that the first condition is satisfied, the camber angle adjusting device is operated to And a first camber angle adjusting means for adjusting at least the camber angle of the turning outer wheel to the first camber angle.   The vehicle control device according to claim 1, wherein the first camber angle is an angle different from a predetermined angle of the camber angle when the vehicle travels straight.   The first camber angle adjusting unit is configured to detect the camber when the second condition determining unit determines that the second condition is satisfied after the first condition determining unit determines that the first condition is satisfied. 3. The vehicle control device according to claim 1, wherein an angle adjusting device is operated to adjust a camber angle of at least a turning outer wheel of the wheels to a first camber angle. 4.   The wheels are operated by operating the camber angle adjusting device, except that the first condition determining means determines that the first condition is satisfied and the second condition determining means determines that the second condition is satisfied. A second camber angle adjusting means for adjusting the camber angle to a second camber angle that is equal to or closer to the predetermined angle than the first camber angle when the vehicle travels straight. The vehicle control device according to claim 1, wherein the vehicle control device is provided. The first condition determination means satisfies the first condition until it is determined that the absolute value of the steering angle is equal to or greater than a first threshold value and is equal to or less than a second threshold value that is smaller than the first threshold value. To judge,
The second condition determining means determines that the second condition is satisfied when it is determined that the time differential value of the absolute value of the steering angle is equal to or less than a predetermined negative value. Item 5. The vehicle control device according to any one of Items 1 to 4. The camber angle adjusting device is disposed on a rear wheel of the wheels,
The vehicle control device according to any one of claims 1 to 5, wherein the first camber angle adjusting means adjusts a camber angle of the rear wheel.   The vehicle control device according to any one of claims 1 to 6, wherein the first camber angle is an angle that changes in a negative direction from a predetermined angle of the camber angle when the vehicle travels straight. .

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