WO2023119424A1

WO2023119424A1 - Leaning vehicle

Info

Publication number: WO2023119424A1
Application number: PCT/JP2021/047352
Authority: WO
Inventors: 圭佑寺田; 誠吾大西
Original assignee: ヤマハ発動機株式会社
Priority date: 2021-12-21
Filing date: 2021-12-21
Publication date: 2023-06-29
Also published as: WO2023120580A1

Abstract

Provided is a leaning vehicle which leans a vehicle body to turn, the leaning vehicle being formed from: a plurality of wheels which include one or two front steered wheels; a handle which is operated by an occupant to change a steering angle of the front steered wheels and a leaning angle of the vehicle body during a turn operation; a leaning device which changes the leaning angle of the vehicle body during the turn; a steering device which changes the steering angle of the front steered wheels during the turn; and a braking device which brakes each wheel. The leaning vehicle controls the leaning device and the steering device such that a lateral acceleration acting on the vehicle body increases, from that in a balanced turn state in which the gravity acting on the vehicle body and a centrifugal force toward the outside of the turn at the steering angle and the leaning angle corresponding to a handle angle during the turn operation by the occupant, to a lateral acceleration set on the basis of the speed of the leaning vehicle. The leaning vehicle limits the leaning angle of the vehicle body when a braking force by the braking device exceeds a threshold value set in advance during the execution of the turn control.

Description

tilting vehicle

The present disclosure relates to a tilting vehicle that turns by tilting its body.

Conventionally, a tilting vehicle that turns by tilting the vehicle body is known. For example, Patent Document 1 discloses a leaning vehicle including two front wheels and one rear wheel. This leaning vehicle can control the state of the vehicle during turns. When the occupant operates the steering wheel to start turning from the straight-ahead state, the direction of the front wheels becomes a steering angle corresponding to the steering operation, and the vehicle body is tilted toward the turning center direction. A tilting vehicle calculates the current ZMP position based on the steering angle and the tilt angle. The ZMP position is a position where an imaginary straight line passing through the center of gravity of the leaning vehicle and parallel to the direction of the resultant force of gravity and inertial force acting on the center of gravity intersects the road surface. Further, the tilting vehicle calculates the target ZMP position based on the steering wheel operation amount by the passenger. The target ZMP position is calculated, for example, from the steering angle and the tilt angle preset according to the amount of operation of the steering wheel. The tilting vehicle controls the steering angle and tilting angle so that the current ZMP position moves to match the target ZMP position. When the occupant returns the steering wheel to the straight-ahead state after completing the turn, the steering angle and the tilt angle become zero, and the leaning vehicle returns to a straight-ahead state.

WO2020-138395

When performing control to change the steering angle and tilt angle from a state in which the vehicle turns at the steering angle and tilt angle based on the operation of the crew, it may be necessary to control the vehicle differently from the conventional one. For example, when a passenger performs a braking operation to apply a brake while the vehicle is turning, there is a possibility that a control content different from the conventional one may be required.

The present disclosure has been made in view of the conventional technology including the above problems, and one of its purposes is to provide a leaning vehicle that differs from conventional leaning vehicles in control during vehicle turning when a passenger performs a braking operation. to provide.

A tilting vehicle according to the present disclosure is a tilting vehicle that turns by tilting a vehicle body, and includes a plurality of wheels including one or two front steered wheels, and a steering angle of the front steered wheels and the A steering wheel operated to change the inclination angle of the vehicle body, a tilting device for changing the inclination angle of the vehicle body when turning, a steering device for changing the steering angle of the front steered wheels when turning, and a brake for braking each wheel. and acting on the vehicle body from a balanced turning state in which the gravity acting on the vehicle body and the centrifugal force toward the turning outer side are balanced at the steering angle and the tilt angle corresponding to the steering wheel angle at the time of turning operation by the crew member. and controlling the tilting device and the steering device so that the lateral acceleration set based on the speed of the tilting vehicle increases, and during execution of the turning control, the braking force of the braking device is applied in advance. When the set threshold value is exceeded, the tilt angle of the vehicle body is restricted.

In the above configuration, the leaning vehicle controls the braking device so that the ABS is activated by the wheel when the slip degree indicating the slip of the wheel on the road surface exceeds a preset reference slip degree. You may

In the above configuration, the threshold value is such that the braking force reaches the threshold value and the vehicle body tilts before the ABS is activated due to an increase in the slip degree of the wheels as the braking force by the braking device increases. It may be set so that the angle is restricted.

According to the tilting vehicle according to the present disclosure, a control different from that of a conventional tilting vehicle is performed when turning by changing the steering angle and the tilt angle of the wheels in response to the turning operation performed by the occupant while traveling straight ahead. be able to.

FIG. 1 is a diagram for explaining an outline of a leaning vehicle according to the present embodiment. FIG. 2 is a diagram for explaining control of the steering angle by the control device. FIG. 3 is a diagram for explaining control of the tilt angle by the control device. FIG. 4 is a diagram for explaining an example of turning control of a leaning vehicle. FIG. 5 is a diagram for explaining a method of determining the steering angle and the tilt angle for making the lateral acceleration acting on the center of gravity of the leaning vehicle equal to the target lateral acceleration. FIG. 6 is a diagram for explaining another method of determining the steering angle and the tilt angle for making the lateral acceleration acting on the center of gravity of the leaning vehicle equal to the target lateral acceleration. FIG. 7 is a diagram showing a specific example of a leaning vehicle. FIG. 8 is a diagram for explaining a specific example of the steering device, the tilting device, and the control device. FIG. 9 is a diagram for explaining the operation of the tilting device. FIG. 10 is a diagram for explaining an example of turning control performed using vehicle speed and steering wheel angle. FIG. 11 is a diagram for explaining an example of turning control performed using feedback control. FIG. 12 is a diagram showing another specific example of a leaning vehicle. FIG. 13 is an external view of the left front wheel portion of the leaning vehicle viewed from the right side. FIG. 14 is a diagram for explaining braking control performed on a leaning vehicle. FIG. 15 is a diagram for explaining a method of setting a reference slip degree during turning control. FIG. 16 is a diagram for explaining tilt restriction control. FIG. 17 is a diagram for explaining the relationship between the limitation of the tilt angle based on the braking force and the ABS control.

A tilting vehicle according to the present disclosure will be described below with reference to the accompanying drawings. A tilt wheel has a plurality of wheels. Although the number of front wheels and rear wheels included in the tilting vehicle is not particularly limited, in the present embodiment, a tilting vehicle including two front wheels and one rear wheel will be described as an example. Hereinafter, the leaning vehicle is simply referred to as "vehicle".

FIG. 1 is a schematic diagram for explaining a vehicle 1 according to this embodiment. With the front of the vehicle 1 as the front, the upper left side of FIG. 1 schematically shows a top view of the vehicle 1 traveling straight ahead, and the front view of the same vehicle 1 is shown below. The right side of FIG. 1 schematically shows a top view and a front view of the vehicle 1 during turning. When the vehicle 1 traveling straight as shown on the left side of FIG. 1 turns, the control device 100 shown in the center of FIG. In the top view of the vehicle 1 during turning shown in the present embodiment, illustration of the inclination of the vehicle 1 is omitted and the direction of the steered wheels is shown. is shown.

The vehicle 1 includes two front wheels 11 (11L, 11R) that are steering wheels, one rear wheel 12 that is a driving wheel, a frame 40, a prime mover 50, a seat 60, and a power transmission section 70. The vehicle 1 is a saddle type vehicle in which a passenger straddles a seat 60 to ride. The motor 50 supported by the frame 40 drives the rear wheels 12 through the power transmission section 70 , so that the vehicle 1 moves forward while rotating the

front wheels

11 and 12 contacting the road surface 700 . The type of prime mover 50 is not particularly limited, and may be an internal combustion engine, an electric motor, or a hybrid prime mover including an engine and an electric motor. The configuration of the power transmission section 70 is also not particularly limited, and may be a configuration including a drive chain or a configuration including a drive shaft.

The vehicle 1 includes a steering wheel 30, a control device 100, a steering device 10 including a steering mechanism 111 and a steering mechanism driving section 110, a tilting device 20 including a tilting mechanism 121 and a tilting mechanism driving section 120, and a braking device 80. include.

The occupant operates the steering wheel 30 to change the steering angle of the front wheels 11 and the tilt angle of the vehicle 1 during turning operation. The handle 30 functions as a turning operation input device. The occupant turns the steering wheel 30 to the left or right to change the orientation of the front wheels 11, which are steered wheels, to the left or right in the direction of travel and to tilt the vehicle 1 toward the center of turning. can be swiveled. The left-right direction referred to with respect to the vehicle 1 in this embodiment is the left-right direction viewed from the occupant of the vehicle 1 .

The steering mechanism 111 can change the directions of the two front wheels 11 in the same direction. The steering mechanism 111 changes the steering angle of the front wheels 11 according to the driving by the steering mechanism driving section 110 . The steering mechanism drive unit 110 can drive the steering mechanism 111 to change the direction of the two front wheels 11 leftward or rightward. As shown in FIG. 1 , the steering angle A indicates the orientation of the front wheels 11 when the orientation of the front wheels 11 is changed to the left or right in the traveling direction, with the orientation of the front wheels 11 traveling straight ahead being 0 degrees.

The tilt mechanism 121 can change the tilt angle of the vehicle 1 to tilt left or right. The tilt mechanism 121 changes the tilt angle of the vehicle 1 according to the drive by the tilt mechanism driving section 120 . The tilt mechanism driving section 120 can drive the tilt mechanism 121 to increase or decrease the tilt angle of the vehicle 1 . When the vehicle 1 tilts, the vehicle body, that is, the entire vehicle 1 including the front wheels 11 and the rear wheels 12 tilts at the same tilt angle. Therefore, as shown in FIG. 1, the inclination angle B can be indicated by the inclination of the front wheels 11 to the left or right, with the angle of the front wheels 11 during straight running being 0 degrees. For example, the inclination angle B of the vehicle 1 is the inclination of the front wheels 11 with respect to the road surface 700 when the direction perpendicular to the road surface 700 is 0 degrees.

The vehicle 1 is a steer-by-wire vehicle in which the steering wheel 30 and the front wheels 11 are separated. When the occupant turns the steering wheel 30, the control device 100 detects the steering wheel angle as the amount of steering wheel operation by the occupant. As shown in FIG. 1, the steering wheel angle C indicates the amount of operation of the steering wheel 30 by the occupant when the direction of the steering wheel 30 during straight running is 0 degrees.

The control device 100 can acquire vehicle information indicating the state of the vehicle 1 . The vehicle information includes steering wheel angle and vehicle speed. For example, when the vehicle is stopped (vehicle speed is zero), when the occupant turns the steering wheel 30 to the right to set the steering wheel angle C to 10 degrees, the control device 100 detects this and controls the steering device 10 to turn the steering angle A of the front wheels 11. to 10 degrees. Specifically, the control device 100 controls the steering mechanism drive unit 110 to drive the steering mechanism 111, so that the front wheels 11 turn to the right and the steering angle A becomes 10 degrees.

The braking device 80 includes a left front brake 81a that brakes the left front wheel 11L, a right front brake 81b that brakes the right front wheel 11R, and a rear brake 81c that brakes the rear wheel 12. The configurations of the left front brake 81a, the right front brake 81b, and the rear brake 81c are not particularly limited, and may be disc brakes, drum brakes, or other brakes. The occupant's braking operation to apply the brake may be performed by manually operating the brake lever or may be performed by operating the brake pedal with the foot.

When the occupant starts turning the vehicle 1 while traveling straight ahead, the control device 100 executes turning control of the vehicle 1 . Further, the control device 100 executes tilt limit control for limiting the tilt angle by changing the upper limit value of the tilt angle of the vehicle 1 during turning based on the braking operation performed by the occupant.

The turning control is a control to turn the vehicle 1 in a state in which the lateral acceleration acting on the center of gravity of the vehicle 1 during turning is increased more than the lateral acceleration at the time of equilibrium. In turning control, the steering angle in the turning direction is added to increase the lateral acceleration, and the vehicle 1 turns in a steering angle additional turning state in which the steering angle is increased from the steering angle at the time of balance. Here, when the vehicle 1 is in balance, the steering angle of the front wheels 11 of the vehicle 1 during turning is made the same as the steering wheel angle (A=C) as when the vehicle is stopped, and the vehicle 1 is tilted toward the turning center side. (B>0), it means that the gravity acting on the center of gravity of the vehicle 1 and the centrifugal force are balanced.

Setting information in which the lateral acceleration is set according to the vehicle speed is prepared in advance, and the control device 100 refers to this setting information to determine the lateral acceleration according to the vehicle speed of the vehicle 1 . The control device 100 controls the steering device 10 and the tilting device 20 so that the lateral acceleration acting on the center of gravity of the vehicle 1 during turning becomes greater than the lateral acceleration during equilibrium.

The tilt limit control is a control that changes the upper limit of the tilt angle of the vehicle 1 based on the braking operation performed by the vehicle 1 during turning. When the occupant performs a braking operation, the braking device 80 causes the vehicle 1 to generate a braking force corresponding to the braking operation. As shown in FIG. 1, the control device 100 monitors this braking force (S1), and when the braking force exceeds a preset threshold value, changes the upper limit of the tilt angle of the vehicle 1 (S2). . For example, the upper limit of the tilt angle of the vehicle 1 is changed to a lower value, and the tilt angle of the vehicle 1 is restricted.

The turning control executed by the vehicle 1 will be described below with reference to FIGS. 2 to 6, and specific examples of the vehicle are shown in FIGS. 7 to 12. FIG. After describing braking control for generating a braking force on the vehicle 1 with reference to FIGS. 13 to 15, tilt limit control will be described with reference to FIGS. 16 and 17. FIG.

<Turn control>
FIG. 2 is a diagram for explaining control of the steering angle by the control device 100. As shown in FIG. FIGS. 2A to 2C show top views of the vehicle 1 during straight running, balancing, and turning control, respectively. FIG. 3 is a diagram for explaining control of the tilt angle by the control device 100. As shown in FIG. FIGS. 3A to 3C show front views of the vehicle 1 during straight running, balancing, and turning control, respectively. FIGS. 3(a)-(c) respectively show front views of the vehicle 1 shown in FIGS. 2(a)-(c).

As shown in FIGS. 2(a) and 3(a), during straight running, the steering angle, steering angle, and tilt angle are 0 degrees, and the vehicle 1 does not experience lateral acceleration. When the occupant operates the steering wheel 30 to set the steering wheel angle to C1 as shown in FIG. The steering angle A1 at this time is equal to the steering wheel angle C1 (A1=C1). Further, according to the steering wheel operation of the passenger, the vehicle 1 tilts toward the center of turning and the tilt angle becomes B1 as shown in FIG. state. A lateral acceleration G1 corresponding to the centrifugal force acts on the center of gravity of the vehicle 1 when balanced. The steering angle A1 does not necessarily have to be equal to the steering wheel angle C1, and the steering angle A1 can be made larger or smaller than the steering wheel angle.

Setting information that the control device 100 uses for turning control is prepared in advance. The setting information includes data indicating the correspondence between vehicle speed and lateral acceleration. The control device 100 uses the setting information to determine the lateral acceleration acting on the center of gravity of the vehicle 1 . The control device 100 detects that the vehicle 1 has started to turn by operating the steering wheel 30, refers to the setting information based on the vehicle speed, and determines the lateral acceleration to act on the center of gravity of the vehicle 1. The control device 100 increases the lateral acceleration acting on the center of gravity of the vehicle 1 by controlling the steering device 10 and the tilt device 20 .

The control device 100 can increase the steering angle of the front wheels 11 even when the occupant maintains the steering wheel angle at C1 during turning. Using this, the control device 100 can perform additional steering control to increase the steering angle of the front wheels 11 during turning from the same angle as the steering wheel angle. The control device 100 controls the steering mechanism drive section 110 to drive the steering mechanism 111, and as shown in FIG. Increase (A2>A1). A steering angle in the turning direction is added to increase the lateral acceleration of the vehicle 1, and the vehicle 1 turns in a steering angle additional turning state in which the steering angle is greater than the steering angle at the time of equilibrium.

A force that changes the tilt angle acts on the vehicle 1 as the steering angle changes. The control device 100 suppresses this change by controlling the tilt mechanism driving section 120 to drive the tilt mechanism 121 . Specifically, as the steering angle increases during turning, a force that tends to raise the vehicle 1, that is, a force that reduces the tilt angle B1 acts on the vehicle 1. The tilt mechanism driver 120 can be controlled to maintain the angle B1. That is, the control device 100 performs control so that the tilt angle B2 during rotation control shown in FIG. 3(c) is the same as the tilt angle B1 during balancing.

In this manner, the control device 100 further increases the steering angle from the turning state in which the gravity and the centrifugal force toward the turning outer side are balanced at the steering angle and the tilt angle according to the turning operation of the vehicle 1. The lateral acceleration acting on the center of gravity is increased to lateral acceleration G2. In addition, the control device 100 can suppress changes in the tilt angle of the vehicle 1 that occur as the steering angle increases.

FIG. 4 is a diagram showing an example of measured values of lateral acceleration obtained by performing turning control of a leaning vehicle. The vehicle 1 controls the steering device 10 and the tilting device 20 from a turning state in which the gravity acting on the vehicle body at the steering angle and the tilting angle according to the turning operation of the occupant is balanced with the centrifugal force toward the turning outer side. 1 is increased to a lateral acceleration set based on the speed of the vehicle 1, and when the speed range up to the maximum speed of the vehicle 1 is divided into five equal regions, The steering device 10 and the tilt device 20 are controlled so that the lateral acceleration change rate with respect to the vehicle speed change becomes smaller than the lateral acceleration change rate with respect to the vehicle speed change in the lowest speed range. The average increase rate of lateral acceleration in the maximum speed range is smaller than the average increase rate of lateral acceleration in the minimum speed range. Also, the average value of the lateral acceleration in the lowest speed range is smaller than the average value of the lateral acceleration in the highest speed range. The lateral acceleration gradually increases in the low vehicle speed range including the lowest speed range, and becomes a constant value in the high vehicle speed range including the maximum speed range.

Data 210a indicated by a dashed line in FIG. 4 indicates the lateral acceleration that the control device 100 applies to the center of gravity of the vehicle 1 by performing turning control. Data 210b indicated by a solid line in FIG. 4 represents an example of measured values of the lateral acceleration acting on the center of gravity of the vehicle 1 during turning control by the control device 100 . The actual measured value of the lateral acceleration varies depending on various factors such as the weight of the occupant, road surface conditions, wind direction, wind speed, equipment of the vehicle 1, setting conditions of the vehicle 1, and the like. Therefore, as shown in FIG. 4, the preset lateral acceleration data 210a may not match the measured lateral acceleration data 210b. The turning control by the control device 100 according to the present embodiment is not limited to control in which the value of the lateral acceleration actually measured by the vehicle 1 matches the lateral acceleration of the preset data 210a. The turning control by the control device 100 includes control indicating that the measured value of the lateral acceleration of the vehicle 1 differs from the data 210a set in the setting information, as indicated by the data 210b. Specifically, in the turning control by the control device 100, the measured value of the lateral acceleration acting on the center of gravity of the vehicle 1 during turning becomes a value that is greater than the lateral acceleration acting on the center of gravity of the vehicle 1 during balancing. control is included.

In the following, for the sake of simplicity of explanation, the control device 100 performs turning control so that the lateral acceleration acting on the center of gravity of the vehicle 1 is the target lateral acceleration, and the steering angle and the tilt angle of the vehicle 1 for obtaining the target lateral acceleration are the target lateral acceleration. The description will be continued by describing the steering angle and the target tilt angle. FIG. 5 is a diagram for explaining a method of determining the steering angle and the tilt angle for making the lateral acceleration acting on the center of gravity of the vehicle 1 equal to the target lateral acceleration. Vmax on the horizontal axis of FIGS. 5A to 5C indicates the maximum speed of the vehicle 1. In FIG. The maximum speed Vmax of the vehicle 1 referred to in the present embodiment is set to be equal to or higher than the actual maximum speed of the vehicle 1 . For example, the maximum speed may be a design value, a value obtained by actually measuring the maximum speed of the vehicle 1, or a value set based on a design value or an actual measurement value.

The solid line data 210 shown in FIG. 5(a) is the data indicating the target lateral acceleration. A target lateral acceleration corresponding to the vehicle speed is preset between lateral acceleration 0 and Ac1. Solid line data 220 shown in FIG. 5(b) indicates the target steering angle. A target steering angle corresponding to the vehicle speed is set in advance between steering angles 0 to D1. The solid line in FIG. 5(c) indicates the target tilt angle. A target tilt angle corresponding to the vehicle speed is set in advance between the tilt angles 0 to D2.

The dashed line in FIG. 5(a) indicates the lateral acceleration during equilibrium. The target lateral acceleration indicated by the solid line data 220 is set so that the difference from the lateral acceleration at equilibrium in the low vehicle speed region is smaller than the difference from the lateral acceleration at equilibrium in the high vehicle speed region. It is The dashed line in FIG. 5(b) indicates the steering angle at the time of balancing. The target steering angle indicated by the solid line data 220 has the same value as the steering angle at equilibrium in a part of the vehicle speed range from 0 (zero) to a predetermined speed, and the steering angle at equilibrium in the other speed regions. The difference from the target steering angle becomes smaller as the vehicle speed becomes higher than the angle. Although FIG. 5(c) does not show the tilt angle when balanced, when the control device 100 performs turning control to maintain the tilt angle when balanced, the target tilt angle shown in FIG. It will match the tilt angle at the time.

When the vehicle speed is high, the vehicle 1 turns with a smaller steering angle and a larger tilt angle of the front wheels 11 than when the vehicle speed is low. In other words, when the vehicle speed is low, the vehicle 1 turns with the steering angle of the front wheels 11 increased and the inclination angle decreased compared to when the vehicle speed is high. Therefore, the higher the vehicle speed, the smaller the target steering angle and the larger the target tilt angle.

FIG. 5(a) is a diagram showing an example of setting information for the control device 100 to determine the lateral acceleration during turning control. The control device 100 controls the steering device 10 and the tilt device 20 so that the target lateral acceleration acts on the center of gravity of the vehicle 1 during turning. For example, the control device 100 may acquire the lateral acceleration of the vehicle 1 and control the steering device 10 and the tilt device 20 so that this lateral acceleration becomes the target lateral acceleration. As a result, the steering angle of the vehicle 1 becomes the target steering angle and the tilt angle becomes the target tilt angle. A method for acquiring lateral acceleration, which is acceleration in the left-right direction of the vehicle 1, is conventionally known, and details thereof will be omitted. ) and the like to obtain the lateral acceleration acting on the center of gravity of the vehicle 1 .

The setting information used by the control device 100 includes data 220 shown in FIG. 5(b) and data 230 shown in FIG. 5(c) instead of or in addition to the data 210 shown in FIG. 5(a). You can In this case, the control device 100 can determine the target steering angle and the target tilt angle by referring to the data 220 and 230 based on the vehicle speed of the vehicle 1 . The control device 100 controls the steering device 10 to set the steering angle of the front wheels 11 to the target steering angle, and controls the tilt device 20 to set the tilt angle of the vehicle 1 to the target tilt angle, thereby acting on the center of gravity of the vehicle 1. The resulting lateral acceleration can be used as a target lateral acceleration corresponding to the vehicle speed.

FIG. 6 is a diagram for explaining another method of determining the steering angle and the tilt angle for making the lateral acceleration acting on the center of gravity of the vehicle 1 equal to the target lateral acceleration. The target steering angle data 221 and the target tilt angle data 231 shown in FIG. 6 are obtained from the data 210, 220, and 230 shown in FIG. Target lateral acceleration Ac1 and target steering angle D1 shown in FIG. 6(a) correspond to lateral acceleration Ac1 shown in FIG. 5(a) and steering angle D1 shown in FIG. 5(b), respectively. The target lateral acceleration Ac1 and the target tilt angle D2 shown in FIG. 6(b) correspond to the lateral acceleration Ac1 shown in FIG. 5(a) and the tilt angle D2 shown in FIG. 5(c), respectively.

Data 221 in FIG. 6(a) indicates the correspondence between the target steering angle and the target lateral acceleration. The smaller the target lateral acceleration, the larger the target steering angle. In other words, the larger the target lateral acceleration, the smaller the target steering angle. Data 231 in FIG. 6B indicates the correspondence between the target tilt angle and the target lateral acceleration. As the target lateral acceleration increases, the target tilt angle increases. In other words, the smaller the target lateral acceleration, the smaller the target tilt angle.

The setting information used by the control device 100 may include data 210 shown in FIG. 5(a), data 221 shown in FIG. 6(a), and data 231 shown in FIG. 6(b). In this case, the control device 100, which has determined the target lateral acceleration based on the vehicle speed of the vehicle 1 with reference to the data 210 of FIG. A target steering angle can be determined and a target lean angle can be determined from the data 231 of FIG. 6(b). The control device 100 controls the steering device 10 and the tilting device 20 to set the steering angle and the tilting angle of the vehicle 1 to the target steering angle and the target tilting angle, respectively. It can be lateral acceleration.

<Specific example of leaning vehicle>
Next, the turning control performed by the vehicle 1 will be described with a specific example. FIG. 7 is a diagram showing a specific example of the vehicle 1. As shown in FIG. A vehicle 1 shown in FIG. 7 includes a steering device 10 including a steering mechanism 111 and a steering mechanism driving section 110, a tilting mechanism 121 and a tilting mechanism driving section, which are disposed inside a vehicle body covered with a cowl 2 that constitutes the exterior of the vehicle 1. It has a tilting device 20 including 120 and a control device 100 . The vehicle 1 includes many components such as an accelerator and a brake in addition to the configuration shown in FIG.

FIG. 8 is a diagram for explaining specific examples of the steering device 10, the tilt device 20, and the control device 100. FIG. In the example shown in FIG. 8, a steering mechanism 111 is driven by a steering actuator 110 functioning as a steering mechanism driving section, and a tilting mechanism 121 is driven by a tilting actuator 120 functioning as a tilting mechanism driving section.

The control device 100 includes a vehicle information acquisition section 101 , a steering angle determination section 102 , a steering actuator control section 103 , a tilt angle determination section 104 and a tilt actuator control section 105 . The vehicle 1 is provided with a vehicle speed detection device 301 that detects the vehicle speed, and the vehicle information acquisition unit 101 acquires the vehicle speed from the vehicle speed detection device 301 . Since the vehicle speed detection device 301 is conventionally known, the description thereof is omitted. be.

The tilt mechanism 121 shown in FIG. 8 is a parallelogram link type tilt mechanism. The tilt mechanism 121 includes an upper arm 501, a lower arm 502, a left member 503, a right member 504, a left suspension 505L and a right suspension 505R.

The upper arm 501 and lower arm 502 are rotatably connected to the head pipe 40 a at the front end of the frame 40 . The left member 503 is rotatably connected to the left ends of the upper arm 501 and the lower arm 502, respectively. A left suspension 505L is connected to the lower end of the left member 503 via a bracket. The left front wheel 11L, which is a steering wheel, is rotatably connected to the left suspension 505L. The left suspension 505L enables vertical movement of the left front wheel 11L with respect to the left member 503. As shown in FIG. The right member 504 is rotatably connected to the right ends of the upper arm 501 and the lower arm 502, respectively. A right suspension 505R is connected to the lower end of the right member 504 via a bracket. A right front wheel 11R, which is a steering wheel, is rotatably connected to the right suspension 505R. The right suspension 505R allows the right front wheel 11R to move up and down with respect to the right member 504. As shown in FIG.

The upper arm 501 and the lower arm 502 rotate around the central axes Ca and Cb on the head pipe 40a, respectively, and the relative positions of the left front wheel 11L and the right front wheel 11R with respect to the frame 40 in the vertical direction of the vehicle body change. The front left wheel 11L and the front right wheel 11R are simultaneously tilted at the same angle.

Specifically, when the vehicle 1 is turned leftward, the tilt actuator 120 rotates the upper arm 501 and the lower arm 502 around the central axes Ca and Cb, respectively, clockwise in FIG. The front wheel 11L and the right front wheel 11R incline leftward. When the vehicle 1 is turned rightward, the tilt actuator 120 rotates the upper arm 501 and the lower arm 502 about the central axes Ca and Cb, respectively, counterclockwise in FIG. The right front wheel 11R inclines rightward.

For example, an electric motor fixed to the frame 40 is used as the tilt actuator 120. The tilt angle determination unit 104 determines the tilt angle of the vehicle 1 by controlling the rotation direction and rotation angle of the output shaft of the electric motor connected to the upper arm 501 or the lower arm 502 by the tilt actuator control unit 105. The tilt angle can be controlled. Control of the tilt actuator 120 is performed by controlling the output torque of the tilt actuator 120, for example.

The steering mechanism 111 includes a steering shaft 401 and a tie rod 402. The steering shaft 401 is inserted into the head pipe 40a and can rotate relative to the head pipe 40a. A central portion of tie rod 402 is connected to a lower end portion of steering shaft 401 . The tie rod 402 moves in the left-right direction as the steering shaft 401 rotates.

The left end of the tie rod 402 is connected to the left suspension 505L that supports the left front wheel 11L. A right end of the tie rod 402 is connected to a right suspension 505R that supports the right front wheel 11R. When the tie rod 402 moves in the left-right direction, the left front wheel 11L and the right front wheel 11R change direction in the left and right direction.

The steering shaft 401 is not mechanically connected to the steering wheel 30. When the passenger turns the steering wheel 30 , the steering actuator control section 103 controls the steering actuator 110 to rotate the steering shaft 401 . When turning the vehicle 1 leftward, the steering actuator 110 rotates the steering shaft 401 so that the right front wheel 11R and the left front wheel 11L turn leftward. When turning the vehicle 1 rightward, the steering actuator 110 rotates the steering shaft 401 so that the left front wheel 11L and the right front wheel 11R turn rightward.

For example, an electric motor fixed to the frame 40 is used as the steering actuator 110. The steering actuator control unit 103 controls the rotation direction and rotation angle of the output shaft of the electric motor connected to the steering shaft 401, thereby controlling the steering angle of the front wheels 11 to the steering angle determined by the steering angle determination unit 102. can do. The control of the steering actuator 110 is performed by controlling the output torque of the steering actuator 110, for example.

When the occupant turns the steering wheel 30 to start the turning operation, the turning control of the vehicle 1 is started. The vehicle information acquisition unit 101 acquires the vehicle speed of the vehicle 1 from the vehicle speed detection device 301 . A steering angle determination unit 102 determines a target lateral acceleration based on the vehicle speed acquired by the vehicle information acquisition unit 101, and determines a target steering angle corresponding to this target lateral acceleration. The steering actuator control unit 103 controls the steering actuator 110 that drives the steering mechanism 111 so that the steering angle of the front wheels 11 becomes the target steering angle determined by the steering angle determination unit 102 .

In addition, the tilt angle determination unit 104 determines the target lateral acceleration based on the vehicle speed acquired by the vehicle information acquisition unit 101, and determines the target tilt angle corresponding to this target lateral acceleration. The tilt actuator control unit 105 controls the tilt actuator 120 that drives the tilt mechanism 121 so that the tilt angle of the vehicle 1 becomes the target tilt angle determined by the tilt angle determination unit 104 . For example, when the steering angle of the vehicle 1 that starts turning and tilts increases, a force acts on the vehicle 1 to raise the vehicle 1 to the outside of the turn, that is, to reduce the tilt angle. The tilt actuator control unit 105 controls the tilt actuator 120 so that the tilted vehicle 1 does not rise to the outside of the turn, that is, the tilt angle does not decrease.

As a result, as described above, the steering angle of the front wheels 11 increases to the target steering angle larger than the steering angle at the time of balancing, and the tilt angle of the vehicle 1 is maintained at the target tilt angle. The lateral acceleration acting on the center of gravity becomes the target lateral acceleration, and the vehicle 1 turns.

FIG. 9 is a diagram for explaining the operation of the tilt actuator 120 that drives the tilt mechanism 121. FIG. The tilt actuator 120 changes the tilt angle of the vehicle 1 by applying torque to the tilt mechanism 121 . For example, the tilt angle of the vehicle 1 is changed by controlling the rotational direction and output torque of the output shaft of the electric motor that functions as the tilt actuator 120 . The value of the output torque of the output shaft is a value that has a proportional relationship with the current value applied to the electric motor.

When the vehicle speed of the vehicle 1 is high, the lateral acceleration acting on the center of gravity of the vehicle 1 that has started turning is greater than when the vehicle speed is low. Further, when the vehicle speed is high, the force that tends to raise the vehicle 1, that is, the force that tends to reduce the inclination angle, generated by increasing the steering angle during turning is greater than when the vehicle speed is low. Therefore, it is necessary to increase the torque of the tilt actuator 120 to suppress this. Therefore, as shown in FIG. 9, the control device 100 controls the tilt actuator 120 so that the torque increases as the lateral acceleration acting on the center of gravity of the vehicle 1 increases. Although FIG. 9 shows an example in which the relationship between lateral acceleration and torque changes linearly, this is an example, and the relationship between lateral acceleration and torque is not limited to this.

A lateral acceleration determination unit may be provided between the vehicle information acquisition unit 101 shown in FIG. 8 and the steering angle determination unit 102 and the tilt angle determination unit 104 . In this case, the lateral acceleration determination unit determines the target lateral acceleration corresponding to the vehicle speed, the steering angle determination unit 102 determines the target steering angle based on the target lateral acceleration, and the tilt angle determination unit 104 determines the target tilt angle. You just have to decide.

The timing at which the tilt actuator control section 105 starts controlling the tilt actuator 120 to obtain the target tilt angle precedes the timing at which the steering actuator control section 103 starts controlling the steering actuator 110 to obtain the target steering angle. may The control gain when the tilt actuator control section 105 controls the tilt actuator 120 may be set larger than the control gain when the steering actuator control section 103 controls the steering actuator 110 . In other words, when the operation of returning the tilt angle to 0 degrees when the vehicle 1 completes turning is compared with the operation of returning the steering angle to 0 degrees when traveling straight, the operation of returning the tilt angle to 0 degrees is found. The control timing and the control gain may be set so as to end earlier.

The control device 100 may control the steering angle and tilt angle of the front wheels 11 based on the vehicle speed and steering wheel angle. FIG. 10 is a diagram for explaining an example of turning control performed using vehicle speed and steering wheel angle. The vehicle information acquisition unit 101 shown in FIG. 10A acquires the vehicle speed from the vehicle speed detection device 301 and also acquires the steering wheel angle from the steering wheel angle detection device 302 . Since the steering wheel angle detection device 302 is conventionally known, the description thereof is omitted. For example, the steering wheel angle is detected using an angle sensor, an encoder, or the like.

FIG. 10(b) is a diagram showing an example of setting information used when performing turning control based on vehicle speed and steering wheel angle. A plurality of data 240 (240a to 240c) having different target lateral accelerations depending on steering wheel angles are prepared in advance. FIG. 10(b) shows an example of three data 240a to 240c, and target acceleration data 240 is prepared for each steering wheel angle.

The larger the steering wheel angle, the larger the target lateral acceleration is set. When the steering wheel angles increase to H1, H2, and H3 (H1<H2<H3), as shown in FIG. , it is set to a value larger than the target lateral acceleration data 40b of the steering wheel angle H2. Similarly, the target lateral acceleration data 240b for the steering wheel angle H2 is set to a value larger than the target lateral acceleration data 240c for the steering wheel angle H1.

For example, as shown in FIG. 10(b), the target lateral acceleration of each data 240 is defined by dividing the speed range from 0 (zero) to the maximum speed Vmax of the vehicle 1 into 5 equal parts. The change rate of the target lateral acceleration with respect to the vehicle speed change in the maximum speed range is set to be smaller than the change rate of the target lateral acceleration with respect to the vehicle speed change in the minimum speed range. The average increase rate of lateral acceleration in the maximum speed range is smaller than the average increase rate of lateral acceleration in the minimum speed range. Each data 240 is set such that the average value of the target lateral acceleration in the lowest speed range is smaller than the average value of the target lateral acceleration in the highest speed range. Each data 240 is set so that the lateral acceleration gradually increases in the low vehicle speed range including the lowest speed range, and becomes a constant value in the high vehicle speed range including the maximum speed range. Each data 240 is set so that the target lateral acceleration increases as the steering wheel angle increases.

When the occupant turns the steering wheel 30 to start the turning operation, the turning control of the vehicle 1 is started. The vehicle information acquisition unit 101 acquires the vehicle speed of the vehicle 1 from the vehicle speed detection device 301 and acquires the steering wheel angle from the steering wheel angle detection device 302 . The steering angle determination unit 102 selects data 240 corresponding to the steering wheel angle acquired by the vehicle information acquisition unit 101 from among the plurality of data 240 . The steering angle determination unit 102 refers to the selected data 240, determines the target lateral acceleration based on the vehicle speed acquired by the vehicle information acquisition unit 101, and determines the target steering angle corresponding to this target lateral acceleration. The steering actuator control section 103 controls the steering actuator 110 so that the steering angle of the front wheels 11 becomes the target steering angle.

Similarly, the tilt angle determination unit 104 selects the data 240 corresponding to the steering wheel angle acquired by the vehicle information acquisition unit 101 from among the plurality of data 240 . The tilt angle determination unit 104 refers to the selected data 240, determines the target lateral acceleration based on the vehicle speed acquired by the vehicle information acquisition unit 101, and determines the target tilt angle corresponding to this target lateral acceleration. The tilt actuator control section 105 controls the steering actuator 110 so that the tilt angle of the vehicle 1 becomes the target tilt angle.

A lateral acceleration determination unit may be provided between the vehicle information acquisition unit 101 and the steering angle determination unit 102 and the tilt angle determination unit 104 . In this case, the lateral acceleration determining section may select the data 240 corresponding to the steering wheel angle and determine the target lateral acceleration corresponding to the vehicle speed on the data 240 . Based on this target lateral acceleration, the steering angle determining section 102 determines the target steering angle, and the tilt angle determining section 104 determines the target tilt angle.

The control device 100 may perform feedback control to control the steering angle and the tilt angle while detecting the steering angle and the tilt angle of the vehicle 1 . FIG. 11 is a diagram for explaining an example of turning control performed using feedback control. A vehicle information acquisition unit 101 shown in FIG. 11 acquires vehicle speed from a vehicle speed detection device 301 and acquires a steering wheel angle from a steering wheel angle detection device 302 . The vehicle information acquisition unit 101 also acquires the tilt angle of the vehicle 1 from the tilt angle detection device 303 and the steering angle of the front wheels 11 from the steering angle detection device 304 . Since the steering angle detection device 304 is conventionally known, the description thereof is omitted. For example, the steering angle is detected using an angle sensor, an encoder, or the like. Since the tilt angle detection device 303 is conventionally known, the description thereof will be omitted.

Based on the vehicle information acquired by the vehicle information acquisition unit 101, the target steering angle is determined by the steering angle determination unit 102, and the target tilt angle is determined by the tilt angle determination unit 104, as described with reference to FIGS. be done.

When the target steering angle is determined, the steering actuator control section 103 starts controlling the steering actuator 110 that drives the steering mechanism 111 . The steering actuator control section 103 can acquire the steering angle of the front wheels 11 detected by the steering angle detection device 304 via the vehicle information acquisition section 101 . The steering actuator control unit 103 checks the steering angle of the front wheels 11 and controls the steering actuator 110 so that this steering angle becomes the target steering angle.

Also, when the target tilt angle is determined, the tilt actuator control unit 105 starts controlling the tilt actuator 120 that drives the tilt mechanism 121 . The tilt actuator control unit 105 can acquire the tilt angle of the vehicle 1 detected by the tilt angle detection device 303 via the vehicle information acquisition unit 101 . The tilt actuator control unit 105 checks the tilt angle of the vehicle 1 and controls the tilt actuator 120 so that the tilt angle becomes the target tilt angle.

Next, another example of the vehicle 1 will be explained. FIG. 12 is a diagram showing another specific example of the vehicle 1. As shown in FIG. This vehicle 1 has a double wishbone type tilting mechanism 121 as shown in FIG. 12(b) on a frame 40 located in front of the steering wheel 30 as shown in FIG. 12(a). The structure and operation of the vehicle 1 shown in FIG. 12 are disclosed, for example, in International Publication No. 2017/082426 filed by the applicant of the present application.

As shown in FIG. 12(b), the tilt mechanism 121 includes an upper left arm 601L, a lower left arm 602L, and an upper right arm 601R and a lower right arm 602R. The upper left arm 601L and the lower left arm 602L have their right ends rotatably connected to the frame 40, and their left ends rotatably connected to the upper and lower ends of the left member 603L. The upper right arm 601R and the lower right arm 602R are rotatably connected to the frame 40 at their left ends, and rotatably connected to the upper and lower ends of the right member 603R at their right ends. The left front wheel 11L is rotatably connected to the left member 603L, and the right front wheel 11R is rotatably connected to the right member 603R. As a result, the left front wheel 11L and the right front wheel 11R can be vertically moved with respect to the frame 40. As shown in FIG.

The lower end of the left damper 605L is rotatably connected to the crossbar forming the lower left arm 602L, and the lower end of the right damper 605R is rotatably connected to the crossbar forming the lower right arm 602R. The upper end of the left damper 605L is rotatably connected to the left end of the connecting portion 630, the upper end of the right damper 605R is rotatably connected to the right end of the connecting portion 630, and the central portion of the connecting portion 630 has a center damper 605L. The upper end of arm 620 is rotatably connected. The lower end of center arm 620 is rotatably connected to frame 40 . As the coupling portion 630 swings left and right around the connection portion with the center arm 620, the upward movement of the left front wheel 11L is transmitted as the downward movement of the right front wheel 11R, and the right front wheel 11R moves upward. is transmitted as downward movement of the left front wheel 11L. The front left wheel 11L moves upward and the right front wheel 11R moves downward, causing the front wheel 11 and the vehicle 1 to lean leftward. incline.

The tilt actuator 120 fixed to the frame 40 drives the center arm 620 so that the center arm 620 swings about its lower end. When the center arm 620 swings, the relative positions of the left front wheel 11L and the right front wheel 11R with respect to the frame 40 via the connecting portion 630 in the vertical direction of the vehicle body change. The control device 100 can control the tilt angle of the vehicle 1 by controlling the rotation direction and rotation angle of the center arm 620 via the tilt actuator 120 .

The steering mechanism 111 of the vehicle 1 shown in FIG. 12(b) includes a steering shaft 401, a left tie rod 402L and a right tie rod 402R. A left tie rod 402L connects the steering shaft 401 and a left member 603L that supports the left front wheel 11L. A steering shaft 401 and a right member 603R supporting the right front wheel 11R are connected by a right tie rod 402R. When the occupant turns the steering wheel 30, the control device 100 controls the steering actuator 110 to move the left tie rod 402L and the right tie rod 402R via the steering shaft 401, so that the left front wheel 11L is moved along the axis shown in FIG. 12(b). It rotates around C2a, and the right front wheel 11R rotates around the axis C2b. The control device 100 can control the steering angle of the front wheels 11 by controlling the direction and amount of movement of the left tie rod 402L and the right tie rod 402R via the steering actuator 110 .

Also in the vehicle 1 shown in FIG. 12, the control device 100 can control the turning of the vehicle 1 by controlling the steering actuator 110 and the tilt actuator 120 as described above.

<Brake control>
Next, braking control will be described. The braking device 80 of the vehicle 1 includes a left front brake 81a that brakes the left front wheel 11L, a right front brake 81b that brakes the right front wheel 11R, and a rear brake 81c that brakes the rear wheel 12. FIG. Although the type of brake is not particularly limited, the following is an example of a disc brake that brakes a wheel by pressing a brake pad to which the hydraulic pressure of the brake fluid is applied according to the braking operation of the occupant against the brake disc fixed to the wheel. continue the explanation.

Fig. 13 is an external view of the left front wheel 11L section viewed from the right side. The left front wheel 11L is provided with a vehicle speed detection device 301a for detecting the wheel speed of the left front wheel 11L. The left front brake 81a includes a left caliper 82a and a left brake disc 83a. The left caliper 82a is fixed to the left suspension 505L. The left brake disc 83a is fixed to the left front wheel 11L. A left front brake pipe 84a is connected to the left caliper 82a. The left caliper 82a has two left brake pads facing each other with a disc-shaped left brake disc 83a interposed therebetween. The left front wheel 11L is braked by the left caliper 82a receiving hydraulic pressure through the left front brake pipe 84a and pressing the brake pads against both surfaces of the left brake disc 83a. Since the right front brake 81b and the rear brake 81c have the same configuration as the left front brake 81a, description thereof will be omitted.

FIG. 14 is a diagram for explaining braking control of the vehicle 1. FIG. The control device 100 includes a vehicle information acquisition section 101 , a braking control section 107 and a hydraulic pressure control section 106 . The control device 100 also includes a left slip degree acquisition unit 108 a , a right slip degree acquisition unit 108 b , a rear slip degree acquisition unit 108 c and a reference slip degree setting unit 109 .

A left front brake 81a that brakes the left front wheel 11L includes a left caliper 82a and a left brake disc 83a. A right front brake 81b that brakes the right front wheel 11R includes a right caliper 82b and a right brake disc 83b. A rear brake 81c for braking the rear wheel 12 includes a rear caliper 82c and a rear brake disc 83c.

The braking device 80 includes two braking operation portions 91 (91a, 91b) and two master cylinders 92 (92a, 92b) provided corresponding to the braking operation portions 91, respectively. The occupant brakes the front wheels 11 and the rear wheels 12 by operating the two brake operation units 91 and changing the hydraulic pressures of the three calipers 82 (82a to 82c) via the hydraulic pressures of the two master cylinders 92. can do. The brake operation unit 91 may be a brake lever operated by the passenger's hand or a brake pedal operated by the passenger's foot. . For convenience of explanation, the first braking operation portion 91a is hereinafter referred to as the left lever 91a, and the second braking operation portion 91b is referred to as the right lever 91b.

When the occupant grips the right lever 91b to apply the brake, the right master cylinder 92b operates to generate hydraulic pressure. The generated hydraulic pressure is transmitted to the hydraulic pressure control section 106 via the right brake pipe 93b. The braking control unit 107 can acquire vehicle information from the vehicle information acquisition unit 101 . The brake control unit 107 causes the hydraulic pressure control unit 106 to generate a hydraulic pressure corresponding to the vehicle information and the hydraulic pressure transmitted from the right brake pipe 93b. For example, in addition to the hydraulic pressure of the right brake pipe 93b, the hydraulic pressure generated by the hydraulic pressure control unit 106 is controlled based on the wheel speeds of the

wheels

11 and 12, the tilting state of the vehicle 1, and the like.

The hydraulic pressure generated by the hydraulic pressure control unit 106 is transmitted to the left caliper 82a via the left front brake pipe 84a, and the left front brake 81a brakes the left front wheel 11L. Similarly, the hydraulic pressure generated by the hydraulic pressure control unit 106 is transmitted to the right caliper 82b via the right front brake pipe 84b, and the right front brake 81b brakes the right front wheel 11R.

When the occupant grips the left lever 91a to apply the brake, the left master cylinder 92a operates to generate hydraulic pressure. The generated hydraulic pressure is transmitted to the hydraulic pressure control section 106 via the left brake pipe 93a. The brake control unit 107 causes the hydraulic pressure control unit 106 to generate hydraulic pressure according to the hydraulic pressure transmitted from the left brake pipe 93a, the wheel speeds of the

wheels

11 and 12, the tilting state of the vehicle 1, and the like.

The hydraulic pressure generated by the hydraulic pressure control unit 106 is transmitted to the left caliper 82a via the left front brake pipe 84a, and the left front brake 81a brakes the left front wheel 11L. Also, the hydraulic pressure generated by the hydraulic pressure control unit 106 is transmitted to the right caliper 82b via the right front brake pipe 84b, and the right front brake 81b brakes the right front wheel 11R. Furthermore, the hydraulic pressure generated by the hydraulic pressure control unit 106 is transmitted to the rear caliper 82c via the rear brake pipe 84c, and the rear brake 81c brakes the rear wheel 12.

That is, when the occupant performs a braking operation with the right lever 91b, the left front wheel 11L and the right front wheel 11R are braked, and when the occupant performs a braking operation with the left lever 91a, the left front wheel 11L, the right front wheel 111R and the rear wheel 12 are braked. be done. However, the hydraulic pressure of the brake fluid filled in the rear brake pipe 84c, the hydraulic pressure of the brake fluid filled in the left front brake pipe 84a, and the hydraulic pressure of the brake fluid filled in the right front brake pipe 84b are independent. It has an adjustable configuration. Therefore, the braking control unit 107 can independently control the rear brake 81c, the left front brake 81a, and the right front brake 81b. The braking control of the vehicle 1 is not limited to front-rear interlocking control in which the front wheels 11 and the rear wheels 12 are braked by operating the left lever 91a. 12 may be braked.

A vehicle speed detection device 301 (301a to 301c) is provided for each of the left front wheel 11L, right front wheel 11R, and rear wheel 12. Vehicle information acquisition unit 101 acquires wheel speeds of

wheels

11 and 12 from vehicle speed detection device 301 . The vehicle information acquisition unit 101 also acquires the tilt angle of the vehicle 1 . For example, the vehicle information acquisition unit 101 acquires the tilt angle from the tilt angle detection device 303 . Further, for example, the vehicle information acquisition unit 101 can also acquire the tilt angle determined by the tilt angle determination unit 104 when turning control is performed.

The left slip degree acquisition unit 108a acquires the slip degree of the left front wheel 11L based on the wheel speed Va of the left front wheel 11L and the vehicle speed V of the vehicle 1. The degree of slip is a measure of the degree of slippage of the tire on the road surface. For example, the slip degree Sa of the left front wheel 11L is calculated by Sa=(Va-V)/V. As the wheel slip on the road increases and the wheel speed Va increases, the value of the slip degree Sa also increases.

Similarly, the right slip degree acquisition unit 108b acquires the slip degree of the right front wheel 11R based on the wheel speed Vb of the right front wheel 11R and the vehicle speed V of the vehicle 1. For example, the slip degree Sb of the right front wheel 11R is calculated by calculating Sb=(Vb−V)/V. The rear slip degree acquiring unit 108 c acquires the slip degree of the rear wheels 12 based on the wheel speed Vc of the rear wheels 12 and the vehicle speed V of the vehicle 1 . For example, the slip degree Sc of the rear wheels 12 is calculated by calculating Sc=(Vc-V)/V.

The reference slip degree setting unit 109 can determine the reference slip degree of each of the front left wheel 11L and the front right wheel 11R based on the tilt angle of the vehicle 1 acquired by the vehicle information acquisition unit 101. The reference slip degree is a slip degree that serves as a threshold value for determining whether or not the ABS should be operated. ABS is activated when the slip degree acquired by the slip degree acquisition unit 108 (108a to 108c) reaches the reference slip degree. The reference slip degrees include a left reference slip degree that is the reference slip degree of the left front wheel 11L, a right reference slip degree that is the reference slip degree of the right front wheel 11R, and a rear reference slip degree that is the reference slip degree of the rear wheel 12. is included.

When the slip degree of the left front wheel 11L acquired by the left slip degree acquisition unit 108a reaches the left reference slip degree, the braking control unit 107 controls the hydraulic pressure control unit 106 to increase the brake fluid filling the left front brake pipe 84a. The ABS of the left front wheel 11L is activated by changing the pressure. The braking control unit 107 automatically activates the ABS regardless of the operation of the passenger.

Similarly, when the slip degree of the right front wheel 11R acquired by the right slip degree acquisition unit 108b reaches the right reference slip degree, the braking control unit 107 controls the hydraulic pressure control unit 106 to fill the right front brake pipe 84b. The ABS of the right front wheel 11R is activated by changing the brake fluid pressure. When the slip degree of the rear wheels 12 acquired by the rear slip degree acquisition unit 109c reaches the rear reference slip degree, the braking control unit 107 controls the hydraulic pressure control unit 106 to increase the brake fluid filling the rear brake pipe 84c. The ABS of the rear wheels 12 is activated by changing the pressure.

The reference slip degree setting unit 109 can change the reference slip degree based on the vehicle information acquired by the vehicle information acquisition unit 101. When the vehicle 1 starts turning and, as described above, the control device 100 increases the steering angle to increase the lateral acceleration acting on the center of gravity of the vehicle 1, when the turning control is performed, the inclination angle of the vehicle 1 is The reference slip degree can be changed according to.

FIG. 15 is a diagram for explaining a method of setting the reference slip degree during turning control. The reference slip degree setting unit 109 sets the reference slip degree according to the tilt angle of the vehicle 1 based on the data 250 indicated by the solid line in FIG. For example, the reference slip degree setting unit 109 can acquire the current tilt angle of the vehicle 1 from the vehicle information acquisition unit 101 and set the reference slip degree corresponding to this tilt angle. Further, for example, when the target tilt angle is determined by turning control, the reference slip degree setting unit 109 can acquire the target tilt angle and set the reference slip degree corresponding to the target tilt angle. The reference slip degree setting unit 109 determines the reference slip degree by a preset method.

In the example shown in FIG. 15, the reference slip degree setting unit 109 maintains the reference slip degree at a constant value S1 in the tilt angle range of 0 to E1, and maintains the reference slip degree at a constant value S1 in the tilt angle range of E1 to E2. The slip degree is linearly reduced, and the reference slip degree is maintained at a constant value S2 in the angle range equal to or greater than the inclination angle E2. However, FIG. 15 is an illustration schematically showing the reference slip degree, and does not limit the value of the reference slip degree.

Data 251 indicated by a dashed line in FIG. 15 indicates the reference slip degree during equilibrium. Specifically, in the balanced turning state shown in FIGS. 2(b) and 3(b), the relationship between the inclination angle and the reference slip degree of a conventional vehicle turning without turning control is shown. ing.

When the vehicle 1 turns, as described above, the turning control is performed to increase the lateral acceleration acting on the center of gravity of the vehicle 1. As shown in FIG. The vehicle 1 turns in the additional turning state with the steering angle increased from the steering angle A1. While the turning control is being performed, the reference slip degree setting unit 109 sets the reference slip degree based on the data 250 indicated by the solid line in FIG. During turning control, the tilt angle is controlled so as to maintain the tilt angle B1 of the vehicle 1 at the time of balancing. When the tilt angle of the vehicle 1 during turning control is the same as the tilt angle during balancing, the reference slip degree for turning control indicated by data 250 is a smaller value than the reference slip degree during balancing indicated by data 251. become.

In the example shown in FIG. 15, the reference slip degree for turning control indicated by the solid line is set to a value smaller than the reference slip degree in equilibrium indicated by the dashed line in the entire tilt angle range. For example, the reference slip degree data 250 during turning control is obtained by translating the data 251 of the reference slip degree during equilibrium by a predetermined value in the direction in which the reference slip degree becomes lower. However, FIG. 15 is only an example, and does not limit the relationship between the reference slip degree during balancing and the reference slip degree during turning control. For example, the reference slip degree during turning control may be the same as the reference slip degree during balancing when the tilt angle is in a predetermined angle range from 0 degree. Further, for example, the difference between the reference slip degree during turning control and the reference slip degree during balancing may have different values depending on the angle range.

The left reference slip degree and the right reference slip degree during turning control may be set to different values. Specifically, the reference slip degree setting unit 109 sets different reference slip degrees for the steered wheel (inner wheel) on the turning center side and the steered wheel (outer wheel) on the outer side during turning of the vehicle 1. good too. In other words, when the vehicle 1 tilts and turns, a different reference slip degree is set for the inner wheel and the outer wheel, with the steered wheel of the left front wheel 11L and the right front wheel 11R being the inner wheel in the direction in which the vehicle 1 is tilted. good too.

The tilt angle information acquired by the vehicle information acquisition unit 101 includes information indicating in which direction the vehicle 1 is leaning, left or right. The reference slip degree setting unit 109 acquires this information, identifies which of the front left wheel 11L and the front right wheel 11R is the inner wheel, and can set different reference slip degrees for the inner and outer wheels.

For example, similar to the data 250 shown in FIG. A reference slip degree for the inner ring is set based on the data, and a reference slip degree for the outer ring is set based on the data for the outer ring. Further, for example, after the reference slip degree setting unit 109 sets the reference slip degree based on the data 250 shown in FIG. can be different values. Specifically, for example, the reference slip degree obtained from the data 250 is used as the reference slip degree of the inner ring, and a value obtained by increasing or decreasing the value of this reference slip degree by a predetermined ratio is used as the reference slip degree of the outer ring. Just do it. The reference slip degree obtained from the data 250 may be used as the reference slip degree for the outer ring, and a value obtained by increasing or decreasing the value of this reference slip degree may be used as the reference slip degree for the inner ring.

The braking control unit 107 executes braking control based on the left reference slip degree, right reference slip degree, and rear reference slip degree set by the reference slip degree setting unit 109 . If there is a wheel whose slip degree acquired by the slip degree acquisition unit 108 has reached the left reference slip degree set by the reference slip degree setting unit 109, ABS is activated.

The braking control unit 107 can be set to activate the ABS of the right front wheel 11R when the ABS of the left front wheel 11L is activated. In this case, when the ABS of the left front wheel 11L is activated, the brake control unit 107 controls the hydraulic pressure control unit 106 to activate the ABS of the right front wheel 11R regardless of the slip ratio of the right front wheel 11R. The braking control unit 107 can activate ABS on both the right front wheel 11R and the rear wheel 12 when the ABS on the left front wheel 11L is activated.

The braking control unit 107 can be set to activate the ABS of the rear wheel 12 when the ABS of the left front wheel 11L is activated. In this case, when the ABS of the left front wheel 11L is activated, the brake control unit 107 controls the hydraulic pressure control unit 106 to activate the ABS of the rear wheel 12 regardless of the slip ratio of the rear wheel 12 .

Similarly, when the slip degree of the right front wheel 11R reaches the right reference slip degree while the vehicle 1 is turning, control is performed to activate the ABS of the right front wheel 11R. Also in this case, in addition to the right front wheel 11R, the ABS of the left front wheel 11L may be set to be activated, or the ABS of the rear wheel 12 may be set to be activated.

Although FIG. 15 shows an example in which the reference slip degree is set based on the tilt angle of the vehicle 1, the reference slip degree setting unit 109 sets the steering wheel angle, tilt angle, and A reference slip degree can be set according to at least one of the lateral accelerations. For example, the reference slip degree setting unit 109 may set the reference slip degree based on the steering wheel angle, or may set the reference slip degree based on the lateral acceleration. Also, an example in which the inner and outer wheels of the vehicle 1 during turning are specified based on the inclination angle of the vehicle 1 has been described, but it is possible to specify the inner and outer wheels based on the steering wheel angle, steering angle, lateral acceleration, and the like. There may be.

<Tilt limit control>
Next, tilt restriction control will be described. As described above, the control device 100 performs turning control for controlling the steering angle and tilt angle of the vehicle 1 during turning, and braking control for generating braking force on the vehicle 1 based on the braking operation of the occupant. The control device 100 further executes tilt limit control for limiting the upper limit of the tilt angle of the vehicle 1 during turning based on the braking force.

FIG. 16 is a diagram for explaining tilt restriction control. As shown in FIG. 16 , data 260 that sets the upper limit of the tilt angle of the vehicle 1 according to the braking force acting on the vehicle 1 is prepared in advance.

For example, as shown in FIG. 16, the upper limit of the tilt angle is set to a constant value F1 from the tilt angle of 0 degrees to the threshold value T1. When the braking force exceeds the threshold value T1, the upper limit value of the tilt angle linearly decreases, and when the braking force reaches the threshold value T2, the upper limit value of the tilt angle becomes the value F2 (F1>F2). After the braking force exceeds the threshold T2, the upper limit of the tilt angle is set to a constant value F2. If the braking force of the vehicle 1 decreases after the upper limit of the inclination angle is changed due to an increase in the braking force while the vehicle 1 is turning, the upper limit is also changed in accordance with the braking force. For example, after the braking force exceeds the threshold value T2 and the upper limit value of the tilt angle is changed from the value F1 to the value F2, when the braking force becomes equal to or less than the threshold value T1, the upper limit value returns from the value F2 to the value F1. .

The control device 100 executes turning control so that the tilt angle of the vehicle 1 during turning does not exceed the upper limit set according to the braking force. When the vehicle 1 starts to turn, if the occupant is not performing a braking operation, or if the occupant is performing a braking operation but the braking force is equal to or less than the threshold value T1, the control device 100 controls the vehicle 1 to Turning control is performed so that the tilt angle does not exceed the upper limit value F1. When the vehicle 1 starts to turn, if the occupant is performing a braking operation and the braking force exceeds the threshold value T1 and is equal to or less than the threshold value T2, the control device 100 sets the upper limit of the tilt angle based on the data 260. A value is set, and turning control is executed so that the tilt angle of the vehicle 1 does not exceed this upper limit value. If the occupant is performing a braking operation when the vehicle 1 starts to turn and the braking force exceeds the threshold value T2, the control device 100 prevents the tilt angle of the vehicle 1 from exceeding the upper limit value F2. to execute turning control. Similarly, while the vehicle 1 is turning, the control device 100 changes the upper limit of the inclination angle based on the braking force, and executes turning control so as not to exceed this upper limit.

For example, the control device 100 starts turning control, and based on the vehicle speed of the vehicle 1, the steering device 10 and the steering device 10 so that the steering angle of the vehicle 1 during turning becomes the target steering angle Dx and the inclination angle becomes the target inclination angle Dy. Assume that the tilting device 20 is to be controlled. Further, it is assumed that the braking force exceeds the threshold value T1 and the upper limit value of the tilt angle is changed to the angle Dz, and this angle Dz is smaller than the target tilt angle Dy (Dz<Dy). In this case, the control device 100 controls the steering device 10 so that the steering angle of the front wheels 11 becomes the target steering angle Dx. As for the tilt angle of the vehicle 1, the control device 100 controls the tilt device 20 so that the tilt angle of the vehicle 1 becomes the target tilt angle Dy if the braking force acting on the vehicle 1 is equal to or less than the threshold value T1. On the other hand, if the braking force exceeds the threshold value T1 and the tilt angle is limited to the angle Dz, the control device 100 adjusts the tilt device 20 so that the tilt angle of the vehicle 1 becomes the angle Dz smaller than the target tilt angle Dy. Control. Further, when the braking force acting on the vehicle 1 exceeds the threshold value T1 and the tilt angle is limited to the angle Dz after the tilt angle of the vehicle 1 reaches the target tilt angle Dy due to the turning control performed by the control device 100, The control device 100 controls the tilt device 20 so that the tilt angle of the vehicle 1 becomes an angle Dz smaller than the target tilt angle Dy, that is, the vehicle 1 is raised to the outside of the turn. Further, when the braking force acting on the vehicle 1 becomes equal to or less than the threshold value T1 after the control device 100 performs turning control and the tilt angle of the vehicle 1 reaches the angle Dz, the control device 100 controls the tilt angle of the vehicle 1. is a target tilt angle Dy larger than the angle Dz, that is, the tilt device 20 is controlled so that the vehicle 1 is tilted toward the inside of the turn.

The braking force used for tilt limit control is, for example, the braking force acting on the vehicle 1 by operating the left front brake 81a, the right front brake 81b, and the rear brake 81c. For example, the braking control unit 107 uses the braking force calculated based on the hydraulic pressure applied to the caliper 82 by the hydraulic pressure control unit 106 to determine whether the braking force exceeds the threshold value. Based on this, the upper limit of the tilt angle is set to a value corresponding to the braking force. However, the determination is not limited to the manner in which the determination is made based on the value of the braking force acting on the vehicle 1 . For example, the determination may be made based on the amount of operation of the brake operation unit 91 by the occupant, may be made based on the hydraulic pressure of the master cylinder 92, or may be made based on the hydraulic pressure of the caliper 82. may Further, the tilt limit control may be performed based on the braking force of the front wheels 11, ie, the steering wheels, without using the braking force of the rear wheels 12, ie, the driving wheels.

FIG. 17 is a diagram for explaining the relationship between the upper limit of the tilt angle based on the braking force and ABS control. Data 260 shown in the upper diagram of FIG. 17 corresponds to the tilt angle upper limit data 260 shown in FIG.

The data 270 shown in the lower diagram of FIG. 17 is a diagram showing the operating conditions of the ABS. When the braking force acting on the vehicle 1 increases and the

wheels

11 and 12 begin to slip, the degree of slip ceases to be 0 (zero) and the degree of slip increases as the braking force increases. When the slip degree increases and reaches the reference slip degree Ts, ABS is activated. The dashed line portion of the data 270 shown in FIG. 17 indicates the operating region of the ABS. In this region, ABS control is actually performed to avoid slipping of the

wheels

11 and 12 by operating the ABS, and the degree of slip changes, so the degree of slip is indicated by a dashed line.

As shown in FIG. 17, the value of the braking force T3 when the slip degree of the

wheels

11 and 12 reaches the reference slip degree Ts and the ABS is activated is the braking force threshold value for changing the upper limit value of the inclination angle of the vehicle 1. It becomes a larger value than T1 and T2 (T1<T2<T3). In other words, the thresholds T1 and T2 are set to values smaller than the value T3 of the braking force applied by the ABS. Therefore, when the braking force acting on the turning vehicle 1 increases due to the braking operation of the occupant, the control for limiting the tilt angle of the vehicle 1 is started first, and then the ABS is activated.

In the present embodiment, the turning control has mainly been described for the control until the vehicle 1 is turned into a turning state. Control is performed to return the angle and the tilt angle to 0 degrees, and the vehicle 1 returns to the straight-ahead state.

In the present embodiment, an example has been described in which the control device 100 detects a change in the steering wheel angle caused by a turning operation by an occupant and starts turning control. It may be a mode in which it is started by detecting a change in angle or the like. The turning operation performed by the passenger includes an operation for changing the steering angle of the front wheels 11 and an operation for changing the tilt angle of the vehicle 1 . When the vehicle 1 turns, the steering wheel angle, that is, the steering angle of the front wheels 11, and the tilt angle of the vehicle 1 change. The control device 100 may decide to start turning control based on a change in at least one of the steering wheel angle, the steering angle, and the tilt angle.

In the present embodiment, an example in which the vehicle 1 has two front wheels 11 that are steering wheels and one rear wheel 12 that is a driving wheel has been described. It may have two rear wheels that are driving wheels, or it may have two front wheels that are steering wheels and two rear wheels that are driving wheels. Also, the present invention is not limited to a mode in which only the rear wheels 12 are driven, and may be a mode in which only the front wheels 11 are driven, or a mode in which both the front wheels 11 and the rear wheels 12 are driven. For example, if an in-wheel motor is used, it is possible to drive the steered wheels. In either case, the steering angle and the tilt angle of the front wheels 11 are controlled as described above, and the lateral acceleration acting on the center of gravity of the vehicle 1 can be set to the target lateral acceleration to turn the vehicle 1 .

The configuration of the steering device 10 shown in this embodiment is an example, and the configuration of the steering device 10 is not particularly limited as long as the steering angle of the steered wheels can be controlled as described above. Similarly, the configuration of the tilt device 20 shown in this embodiment is an example, and the configuration of the tilt device 20 is not particularly limited as long as the tilt angle of the steered wheels can be controlled as described above. Further, since the entire vehicle 1 including the front wheels 11, the rear wheels 12, and the vehicle body inclines at the same angle during turning, in the above example, the control for changing the inclination angle of the vehicle 1 is performed by adjusting the inclination of the vehicle body of the vehicle 1. It corresponds to the control to change the angle.

In the present embodiment, for turning control, the vehicle speed, steering wheel angle, etc. are used as input values, and output values such as target lateral acceleration, target steering angle, and target tilt angle are obtained. However, these processes may be performed using a two-dimensional map or an arithmetic expression that indicates the relationship between the input value and the output value. Moreover, the aspect using a three-dimensional map may be sufficient. For example, the target lateral acceleration and the target tilt angle may be determined from the vehicle speed using a three-dimensional map showing the relationship between the vehicle speed, the target steering angle and the target tilt angle for obtaining the target lateral acceleration. Similarly, the setting of the reference slip degree in braking control may be performed using a map or an arithmetic expression.

Regarding the turning control described in the present embodiment, the execution order of the steering angle control by the steering device 10 and the tilt angle control by the tilt device 20 is not particularly limited. The control of the steering angle and the control of the tilt angle may be executed in parallel. The control of the steering angle may be performed after performing the control to increase the tilt angle first. Control for increasing the steering angle may be performed first, and then control for the tilt angle may be performed. For example, the control device 100 may gradually increase the steering angle of the front wheels 11 and the tilt angle of the vehicle 1 to the target steering angle and the target tilt angle.

1 vehicle 2 cowl 10 steering device 11 (11L, 11R) front wheel 12 rear wheel 20 tilting device 30 steering wheel 40 frame 50 prime mover 60 seat 70 power transmission unit 80 braking device 91 braking operation unit 100 control device 110 steering mechanism driving unit (steering actuator )
111 steering mechanism 120 tilting mechanism driving unit (tilting actuator)
121 Tilt Mechanism

Claims

A tilting vehicle that turns by tilting the vehicle body,
a plurality of wheels, including one or two front steerable wheels;
a handle operated by an occupant to change a steering angle of the front steered wheels and an inclination angle of the vehicle body during a turning operation;
a tilt device for changing the tilt angle of the vehicle body when turning;
a steering device that changes the steering angle of the front steered wheels when turning;
A braking device for braking each wheel,
The lateral acceleration acting on the vehicle body from a balanced turning state in which the gravity acting on the vehicle body at the steering angle and the tilt angle corresponding to the steering wheel angle and the tilt angle corresponding to the steering wheel angle during the turning operation by the occupant and the centrifugal force toward the turning outer side are balanced, controlling the tilting device and the steering device so as to increase the lateral acceleration set based on the speed of the tilting vehicle; A tilting vehicle, wherein the tilting angle of the vehicle body is limited when exceeding the tilting angle.
If there is a wheel whose slip degree indicating the slip of said wheel on the road surface exceeds a preset reference slip degree, said braking device is controlled to activate ABS at said wheel. A leaning vehicle according to claim 1.
The threshold is such that the braking force reaches the threshold and the tilt angle of the vehicle body is limited before ABS is activated by increasing the slip degree of the wheels as the braking force of the braking device increases. 3. A leaning vehicle according to claim 2, characterized in that it is set so that: