JP2013071688A - Vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle capable of maintaining the stability of a vehicle body, improving turning performance and achieving a stable and comfortable traveling state without giving a rider a sense of incongruity.SOLUTION: The vehicle includes the vehicle body having a steering part and a body part connected to each other; a steerable steered wheel for steering the vehicle body; non-steerable non-steered wheels; a link mechanism for inclining the steering part or the body part in a turning direction; an inclining actuator device for operating the link mechanism; a rotational driving device imparting driving force to the steered wheel or the non-steered wheels; a driving command device for inputting a driving force generation command; and a control device for controlling the inclining actuator device and the rotational driving device. The control device limits the driving force generation command when the absolute value of a change of at least one value out of the steering amount of the steered wheel, the link angle of the link mechanism, and a yaw rate is larger than a predetermined value.

Description

  The present invention relates to a vehicle having at least a pair of left and right wheels.

  In recent years, in view of the problem of depletion of energy resources, there has been a strong demand for fuel saving of vehicles. On the other hand, the number of vehicle owners is increasing due to the low price of vehicles, and one person tends to own one vehicle. Therefore, for example, there is a problem that energy is wasted when only one driver drives a four-seater vehicle. The most efficient way to save fuel consumption by reducing the size of the vehicle is to configure the vehicle as a one-seater tricycle or four-wheel vehicle.

  However, depending on the running state, the stability of the vehicle may decrease. Therefore, a technique for improving the stability of the vehicle during turning by tilting the vehicle body in the lateral direction has been proposed (for example, see Patent Document 1).

JP 2008-155671 A

  However, in the conventional vehicle, in order to improve the turning performance, the vehicle body can be tilted inward in the turning direction. However, the tread is affected by the centrifugal force acting outward in the turning direction. When the vehicle is narrow, when the position of the center of gravity is high, or when the steering speed is high, the stability of the vehicle is likely to decrease, and the passenger may feel uncomfortable or feel uneasy.

  The present invention solves the problems of the conventional vehicle, and when the change in at least one of the steering amount, the link angle of the link mechanism for tilting the vehicle body, and the yaw rate is greater than a predetermined value, the driving force By restricting the generation command, even when the tread is narrow, the center of gravity is high, or the steering speed is high, the vehicle body can be smoothly tilted inward in the turning direction. Provides a highly safe vehicle that can maintain the vehicle's driving performance, improve turning performance, provide a comfortable ride, and realize a stable driving condition without causing the passengers to feel uncomfortable. The purpose is to do.

  Therefore, in the vehicle of the present invention, a vehicle body including a steering unit and a main body unit that are connected to each other, a wheel that is rotatably attached to the steering unit, and a steerable steering wheel that steers the vehicle body, A non-steering wheel that is rotatably attached to the main body and cannot be steered; a link mechanism that tilts the steering part or the main body in a turning direction; and an actuator device for tilting that operates the link mechanism A rotation drive device that applies a drive force to the steered wheel or the non-steer wheel, a drive command device that inputs a drive force generation command, and a control device that controls the tilt actuator device and the rotation drive device. When the absolute value of the change in at least one of the steering amount of the steered wheel, the link angle of the link mechanism, and the yaw rate is greater than a predetermined value, the control device To limit the power generation command.

  According to the configuration of the first aspect, since the driving force is not exhibited when the stability of the vehicle body tends to be lowered, the stability of the vehicle body can be maintained without sacrificing the maneuverability and the crisis avoidance performance.

  According to the configuration of claim 2, when the occupant starts turning the steering wheel, when the steering wheel is turned up, when the vehicle body starts to tilt, when the tilting is increased, or when turning is started, Or, when the yaw rate increases, the rotational drive device prevents the driving force from being exerted, so that not only the stability of the vehicle body can be maintained, but also the vehicle body tends to tilt inward in the turning direction and the turning performance is improved. To do.

  According to the configuration of the third aspect, since the restriction on the driving force generation command is released while the vehicle body is stable, the vehicle body does not become unstable even if the rotational driving device exerts the driving force.

  According to the configuration of the fourth aspect, the driving force generation command can be more appropriately limited, and the stability of the vehicle body can be more effectively maintained.

It is a right view which shows the structure of the vehicle in embodiment of this invention. It is a figure which shows the structure of the link mechanism of the vehicle in embodiment of this invention. It is a rear view which shows the structure of the vehicle in embodiment of this invention. It is a block diagram which shows the structure of the vehicle body tilt control system in embodiment of this invention. It is a block diagram of a control system in an embodiment of the present invention. It is a figure which shows the dynamic model explaining the inclination operation | movement of the vehicle body at the time of turning driving | running | working in embodiment of this invention. It is a flowchart which shows the operation | movement of the lateral acceleration calculation process in embodiment of this invention. It is a flowchart which shows the operation | movement of the link angular velocity estimation process in embodiment of this invention. It is a flowchart which shows the subroutine of the differentiation process of the yaw rate in embodiment of this invention. It is a flowchart which shows the subroutine of the filter process in embodiment of this invention. It is a flowchart which shows the operation | movement of the inclination control process in embodiment of this invention. It is a flowchart which shows the operation | movement of the steering control process in embodiment of this invention. It is a flowchart which shows the operation | movement of the link motor control process in embodiment of this invention. It is a block diagram of the control system which restrict | limits the driving force generation | occurrence | production command in embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1 is a right side view showing a configuration of a vehicle in an embodiment of the present invention, FIG. 2 is a diagram showing a configuration of a link mechanism of the vehicle in the embodiment of the present invention, and FIG. 3 is a vehicle in the embodiment of the present invention. It is a rear view which shows the structure. 3A is a diagram showing a state where the vehicle body is standing upright, and FIG. 3B is a diagram showing a state where the vehicle body is inclined.

  In the figure, reference numeral 10 denotes a vehicle according to the present embodiment, which includes a main body 20 as a vehicle body drive unit, a riding unit 11 as a steering unit on which an occupant gets on and steer, and a center in the width direction in front of the vehicle body. A wheel 12F as a steerable steering wheel which is a front wheel disposed on the left side, and a left wheel 12L and a right wheel 12R as non-steering wheels which are drive wheels disposed rearward as rear wheels and cannot be steered. And have. Furthermore, the vehicle 10 operates as a lean mechanism for leaning the vehicle body from side to side, that is, as a lean mechanism, that is, a vehicle body tilt mechanism, supporting the left and right wheels 12L and 12R, and the link mechanism 30. And a link motor 25 as a tilt actuator device. The vehicle 10 may be a three-wheeled vehicle with two front wheels on the left and right and one wheel on the rear, or may be a four-wheeled vehicle with two wheels on the left and right. As shown in the figure, a case will be described in which the front wheel is a single wheel and the rear wheel is a left and right tricycle. Further, although the steered wheel may function as a drive wheel, in the present embodiment, the description will be made assuming that the steered wheel does not function as a drive wheel.

  When turning, the angle of the left and right wheels 12L and 12R with respect to the road surface 18, that is, the camber angle is changed, and the vehicle body including the riding portion 11 and the main body portion 20 is inclined toward the turning inner wheel, thereby improving turning performance and the occupant. It is possible to ensure the comfort of the car. That is, the vehicle 10 can tilt the vehicle body in the lateral direction (left and right direction). In the example shown in FIGS. 2 and 3 (a), the left and right wheels 12L and 12R are upright with respect to the road surface 18, that is, the camber angle is 0 degree. In the example shown in FIG. 3B, the left and right wheels 12L and 12R are inclined in the right direction with respect to the road surface 18, that is, a camber angle is given.

  The link mechanism 30 includes a left vertical link unit 33L that supports a left wheel 12L and a left rotation driving device 51L including an electric motor that applies driving force to the wheel 12L, a right wheel 12R, and the wheel 12R. A right vertical link unit 33R that supports a right rotation drive device 51R composed of an electric motor or the like that applies a driving force to an upper side, and an upper horizontal link unit 31U that connects the upper ends of the left and right vertical link units 33L and 33R; The lower horizontal link unit 31D that connects the lower ends of the left and right vertical link units 33L and 33R, and the central vertical member 21 that has an upper end fixed to the main body 20 and extends vertically. The left and right vertical link units 33L and 33R and the upper and lower horizontal link units 31U and 31D are rotatably connected. Further, the upper and lower horizontal link units 31U and 31D are rotatably connected to the central vertical member 21 at the center thereof. When the left and right wheels 12L and 12R, the left and right rotational drive devices 51L and 51R, the left and right vertical link units 33L and 33R, and the upper and lower horizontal link units 31U and 31D are described in an integrated manner, The rotation drive device 51, the vertical link unit 33, and the horizontal link unit 31 will be described.

  The rotary drive device 51 as a drive actuator device is a so-called in-wheel motor, and a body as a stator is fixed to the vertical link unit 33 and is a rotor attached to the body so as to be rotatable. A rotating shaft is connected to the shaft of the wheel 12, and the wheel 12 is rotated by the rotation of the rotating shaft. The rotational drive device 51 may be a motor other than an in-wheel motor.

  The link motor 25 is a rotary electric actuator including an electric motor or the like, and includes a cylindrical body as a stator and a rotating shaft as a rotor rotatably attached to the body. The body is fixed to the main body portion 20 via the mounting flange 22, and the rotating shaft is fixed to the lateral link unit 31 </ b> U on the upper side of the link mechanism 30. The rotation axis of the link motor 25 functions as an inclination axis for inclining the main body 20 and is coaxial with the rotation axis of the connecting portion between the central vertical member 21 and the upper horizontal link unit 31U. When the link motor 25 is driven to rotate the rotation shaft with respect to the body, the upper horizontal link unit 31U rotates with respect to the main body 20 and the central vertical member 21 fixed to the main body 20, The link mechanism 30 operates, that is, bends and stretches. Thereby, the main-body part 20 can be inclined. Note that the rotation axis of the link motor 25 may be fixed to the main body 20 and the central vertical member 21, and the body may be fixed to the upper horizontal link unit 31U.

  The link motor 25 includes a link angle sensor 25 a that detects a change in the link angle of the link mechanism 30. The link angle sensor 25a is a rotation angle sensor that detects the rotation angle of the rotation shaft with respect to the body in the link motor 25, and includes, for example, a resolver, an encoder, and the like. As described above, when the link motor 25 is driven to rotate the rotation shaft with respect to the body, the upper horizontal link unit 31U rotates with respect to the main body 20 and the central vertical member 21 fixed to the main body 20. Therefore, a change in the angle of the upper horizontal link unit 31U relative to the central vertical member 21, that is, a change in the link angle can be detected by detecting the rotation angle of the rotation shaft with respect to the body.

  The link motor 25 includes a lock mechanism (not shown) that fixes the rotation shaft to the body so as not to rotate. The lock mechanism is a mechanical mechanism, and preferably does not consume electric power while the rotation shaft is fixed to the body so as not to rotate. The lock mechanism can fix the rotation shaft so as not to rotate at a predetermined angle with respect to the body.

  The riding part 11 is connected to the front end of the main body part 20 via a connecting part (not shown). The connecting part may have a function of connecting the riding part 11 and the main body part 20 so as to be relatively displaceable in a predetermined direction.

  The boarding part 11 includes a seat 11a, a footrest 11b, and a windbreak part 11c. The seat 11 a is a part for a passenger to sit while the vehicle 10 is traveling. The footrest 11b is a part for supporting the occupant's foot, and is disposed on the front side (right side in FIG. 1) and below the seat 11a.

  Further, a battery device (not shown) is disposed behind or below the riding section 11 or on the main body section 20. The battery device is an energy supply source for the rotation drive device 51 and the link motor 25. In addition, a control device, an inverter device, various sensors, and the like (not shown) are accommodated in the rear portion or the lower portion of the riding portion 11 or in the main body portion 20.

  A steering device 41 is disposed in front of the seat 11a. The steering device 41 includes members necessary for steering such as a handlebar 41a as a steering device that is operated by an occupant to input steering command information such as a steering direction and a steering angle, a meter such as a speed meter, an indicator, and a switch. It is arranged. The occupant operates the handle bar 41a and other members to instruct the traveling state of the vehicle 10 (for example, traveling direction, traveling speed, turning direction, turning radius, etc.). As the steering device, other devices such as a steering wheel, a jog dial, a touch panel, and a push button can be used instead of the handle bar 41a.

  The wheel 12F is connected to the riding section 11 via a front wheel fork 17 that is a part of a suspension device (suspension device). The suspension device is a device similar to a suspension device for front wheels used in, for example, general motorcycles, bicycles, and the like, and the front wheel fork 17 is, for example, a telescopic type fork with a built-in spring. Then, as in the case of a general motorcycle, bicycle, etc., the wheel 12F as the steering wheel changes the steering angle in accordance with the operation of the handlebar 41a by the occupant, thereby changing the traveling direction of the vehicle 10.

  Specifically, the handle bar 41a is connected to the upper end of a steering shaft member (not shown), and the upper end of the steering shaft member is rotatably attached to a frame member (not shown) provided in the riding section 11. The steering shaft member is attached to the frame member in an obliquely inclined state so that the upper end is located behind the lower end. The rotation angle of the upper end of the steering shaft member with respect to the frame member, that is, the steering angle as the steering angle command value input by the occupant operating the handle bar 41a is determined by the steering angle sensor 62 as the input steering angle detection means. Detected. The handle angle sensor 62 includes, for example, an encoder.

A steering motor 65 as a steering actuator device is disposed between the upper end and the lower end of the steering shaft member, and the steering motor 65 has a handle angle detected by the handle angle sensor 62. Based on this, the lower end of the steering shaft member is rotated. The lower end of the steering shaft member is rotatably attached to the frame member and is connected to the upper end of the front wheel fork 17. The rotation angle of the lower end of the steering shaft member relative to the frame member, that is, the steering angle output from the steering motor 65 and transmitted to the wheel 12F via the front wheel fork 17 is the steering angle as output steering angle detection means. It is detected by the sensor 63. The steering angle sensor 63 is, for example, a rotation angle sensor that detects the rotation angle of the rotation shaft with respect to the body in the steering motor 65, and includes a resolver, an encoder, and the like. The distance between the left and right wheels 12L and 12R axle is the axle and the rear wheel of the wheel 12F is a front wheel, i.e., the wheel base is L _H.

  Further, the vehicle 10 includes a throttle grip 35 as a drive command device that inputs a drive force generation command as a part of the control device 41. The throttle grip 35 is a member similar to a throttle grip used in a general motorcycle or the like, and is rotatably attached to one end of the handle bar 41a. According to the rotation angle, that is, the throttle opening, This is a device for inputting a driving force generation command as a command for causing the rotational driving device 51 to generate a driving force. Instead of the throttle grip 35, a throttle lever that is a lever-type input device and a throttle pedal that is a pedal-type input device can be used as a drive command device that inputs a drive force generation command.

  A vehicle speed sensor 54 as vehicle speed detecting means for detecting the vehicle speed, which is the traveling speed of the vehicle 10, is disposed at the lower end of the front wheel fork 17 that supports the axle of the wheel 12F. The vehicle speed sensor 54 is a sensor that detects the vehicle speed based on the rotational speed of the wheel 12F, and includes, for example, an encoder.

  In the present embodiment, the vehicle 10 has a lateral acceleration sensor 44. The lateral acceleration sensor 44 is a sensor composed of a general acceleration sensor, a gyro sensor, or the like, and detects the lateral acceleration of the vehicle 10, that is, the acceleration in the lateral direction (horizontal direction in FIG. 3) as the width direction of the vehicle body. To do.

  Since the vehicle 10 is stabilized by inclining the vehicle body toward the inside of the turn at the time of turning, the vehicle 10 is controlled so that the centrifugal force to the outside of the turn at the time of turning and the gravity are balanced by turning the vehicle body. By performing such control, for example, even if the road surface 18 is inclined in a direction perpendicular to the traveling direction (left and right direction with respect to the traveling direction), the vehicle body can always be kept horizontal. As a result, the vehicle body and the occupant are apparently always subjected to gravity downward in the vertical direction, the sense of incongruity is reduced, and the stability of the vehicle 10 is improved.

  Therefore, in the present embodiment, in order to detect the lateral acceleration of the leaning vehicle body, the lateral acceleration sensor 44 is attached to the vehicle body, and feedback control is performed so that the output of the lateral acceleration sensor 44 becomes zero. As a result, the vehicle body can be tilted to an inclination angle at which the centrifugal force acting during turning and gravity are balanced. Further, even when the road surface 18 is inclined in a direction perpendicular to the traveling direction, the vehicle body can be controlled to have an inclination angle that makes the vehicle body vertical. The lateral acceleration sensor 44 is disposed so as to be positioned at the center in the width direction of the vehicle body, that is, on the longitudinal axis of the vehicle body.

  However, if there is one lateral acceleration sensor 44, an unnecessary acceleration component may be detected. For example, while the vehicle 10 is traveling, only one of the left and right wheels 12L and 12R may fall into the depression on the road surface 18. In this case, since the vehicle body is tilted, the lateral acceleration sensor 44 is displaced in the circumferential direction and detects the acceleration in the circumferential direction. That is, an acceleration component that is not directly derived from centrifugal force or gravity, that is, an unnecessary acceleration component is detected.

  In addition, the vehicle 10 includes a portion that functions as a spring and has elasticity like the tire portions of the left and right wheels 12 </ b> L and 12 </ b> R. For this reason, the lateral acceleration sensor 44 is considered to be attached to the vehicle body through inevitable play and springs, and therefore acceleration generated by the displacement of the play and springs is also detected as an unnecessary acceleration component.

  Such an unnecessary acceleration component may deteriorate the controllability of the vehicle body tilt control system. For example, if the control gain of the vehicle body tilt control system is increased, control system vibration, divergence, and the like due to unnecessary acceleration components occur, so that it is not possible to increase the control gain even if responsiveness is to be improved. .

  Therefore, in the present embodiment, a plurality of lateral acceleration sensors 44 are provided at different heights. In the example shown in FIGS. 1 and 3, there are two lateral acceleration sensors 44, a first lateral acceleration sensor 44a and a second lateral acceleration sensor 44b, which are a first lateral acceleration sensor 44a and a second lateral acceleration sensor 44b. Are arranged at different height positions. By appropriately selecting the positions of the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b, unnecessary acceleration components can be effectively removed.

Specifically, as shown in FIG. 3 (a), the first lateral acceleration sensor 44a is in the back of the riding section 11, the distance from the road surface 18, i.e., is disposed at the position of L ₁ Height ing. The second lateral acceleration sensor 44b is the upper surface of the rear or body portion 20 of the riding portion 11, the distance from the road surface 18, i.e., is disposed at a position of L ₂ height. Note that L ₁ > L ₂ . When turning, when the vehicle is turned with the vehicle body tilted inward (right side in the drawing) as shown in FIG. 3B, the first lateral acceleration sensor 44a detects the lateral acceleration. The detection value a ₁ is output, and the second lateral acceleration sensor 44b detects the lateral acceleration and outputs the detection value a ₂ . Although the center of the tilting motion when the vehicle body tilts, that is, the roll center, is strictly located slightly below the road surface 18, it is considered that the center is substantially equal to the road surface 18 in practice.

It is desirable that both the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b are attached to a sufficiently rigid member. Further, if the difference between L ₁ and L ₂ is small, the difference between the detection values a ₁ and a ₂ is small. Therefore, it is desirable that the difference be sufficiently large, for example, 0.3 [m] or more. Furthermore, it is desirable that both the first lateral acceleration sensor 44 a and the second lateral acceleration sensor 44 b are disposed above the link mechanism 30. Further, when the vehicle body is supported by a spring such as a suspension, it is desirable that both the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b are arranged on a so-called “spring top”. Further, both the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b may be disposed between the axle of the front wheel 12F and the axles of the left and right wheels 12L and 12R as rear wheels. desirable. Furthermore, it is desirable that both the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b are disposed as close to the occupant as possible. Further, both the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b are preferably located on the central axis of the vehicle body extending in the traveling direction when viewed from above, that is, not offset with respect to the traveling direction. .

  In the present embodiment, a roll rate sensor 44c for detecting the angular velocity of the tilting motion of the vehicle body and a yaw rate sensor 44d as a yaw angular velocity detecting means for detecting the angular velocity of the turning motion of the vehicle body, that is, the yaw angular velocity of the vehicle body are arranged. It is installed. Specifically, it is desirable that both the roll rate sensor 44c and the yaw rate sensor 44d are located on the central axis of the vehicle body extending in the traveling direction when viewed from above, that is, not offset with respect to the traveling direction. It is arranged between the seat 11a and the footrest 11b.

  The roll rate sensor 44c is a general roll rate sensor, and for example, a gyro sensor is attached so as to detect a rotational angular velocity in a plane perpendicular to the road surface 18. . The yaw rate sensor 44d is a general yaw rate sensor, and for example, a gyro sensor is attached so as to detect a rotational angular velocity in a plane parallel to the road surface 18. Note that the three-dimensional gyro sensor can exhibit the functions of the roll rate sensor 44c and the yaw rate sensor 44d. That is, the roll rate sensor 44c and the yaw rate sensor 44d may be configured separately or may be configured integrally.

  The vehicle 10 in the present embodiment has a vehicle body tilt control system as a part of the control device. The vehicle body tilt control system is a kind of computer system, and includes a tilt control device and a steering control device including an ECU (Electronic Control Unit) or the like.

  The tilt control device includes arithmetic means such as a processor, storage means such as a magnetic disk and a semiconductor memory, an input / output interface, and the like, and includes a link angle sensor 25a, a first lateral acceleration sensor 44a, a second lateral acceleration sensor 44b, a roll rate. It is connected to a sensor 44c, a yaw rate sensor 44d, a vehicle speed sensor 54, a throttle grip 35, a rotary drive device 51 that is an in-wheel motor, a link motor 25, and the like. The tilt control device calculates a throttle opening target value as an output value of the driving force generation command based on the rotation angle of the throttle grip 35, that is, the throttle opening as the input value of the driving force generation command. The rotation drive device 51 is operated. Further, the tilt control device outputs a torque command value for operating the link motor 25.

  Further, the steering control device includes a calculation means such as a processor, a storage means such as a magnetic disk and a semiconductor memory, an input / output interface, and the like, and is connected to a handle angle sensor 62, a steering angle sensor 63, a vehicle speed sensor 54, and a steering motor 65. Has been. The steering control device outputs a control pulse for operating the steering motor 65. The tilt control device and the steering control device are connected to each other. In addition, the tilt control device and the steering control device are not necessarily configured separately, and may be configured integrally.

  The tilt control device performs feedback control and feedforward control during turning, so that the tilt angle of the vehicle body is such that the lateral acceleration value detected by the lateral acceleration sensor 44 becomes an angle that becomes zero. The motor 25 is operated. That is, the tilt angle of the vehicle body is controlled so that the centrifugal force to the outside of the turn balances with the gravity and the lateral acceleration component becomes zero. As a result, a force in a direction parallel to the longitudinal axis of the vehicle body acts on the vehicle body and the occupant on the riding section 11. Therefore, the stability of the vehicle body can be maintained and the turning performance can be improved.

  Also, when a disturbance in the tilt direction is received, a part due to the disturbance in the change in the tilt angle of the vehicle body is extracted, and for the remaining part, the tilt angle of the vehicle body is controlled in the normal mode, and the extracted part In contrast, the vehicle body tilt angle is controlled in the disturbance response mode. Therefore, the stability of the vehicle body can be maintained even when subjected to disturbance. In addition, the rider does not feel discomfort and the ride comfort is improved.

  Further, in the present embodiment, the driving force generation command is limited when the turning traveling is started. That is, the acceleration command value is limited when a change in at least one of a steering wheel angle as a steering amount, a link angle as an operation amount of the tilting actuator device, and a yaw rate becomes larger than a predetermined value.

  More specifically, when at least one of the steering wheel angle, the link angle, and the yaw rate has the same sign as the differential value, the throttle opening target value is controlled to be zero regardless of the throttle opening value. To do. That is, when the occupant starts turning the steering wheel, or when the steering wheel is turned up, when the link mechanism 30 starts to tilt, when the tilting increases, when the vehicle 10 starts turning, or When the yaw rate increases, the rotational drive device 51 is prevented from exerting a driving force.

  As a result, when the stability of the vehicle 10 is likely to decrease, the rotational driving device 51 does not exhibit the driving force, and thus it is possible to reliably prevent a decrease in stability. In addition, since the rotational drive device 51 does not exert a driving force, the vehicle body is easily inclined inward in the turning direction, and the turning performance is improved. Accordingly, when the stability of the vehicle 10 is likely to be lowered immediately after the start of turning, the driving force is not applied to the left and right wheels 12L and 12R as driving wheels, so that the stability of the vehicle 10 can be reliably maintained. it can.

  When the vehicle body tilt control is performed without performing such steering control, for example, when the tread (the distance between the ground contact points of the left and right wheels 12L and 12R) is narrow, when the center of gravity of the vehicle 10 is high, When the speed (the speed at which the steering wheel is turned) is high, the centrifugal force generated by turning acts as a force for inclining the vehicle body outward in the turning direction. May decrease. However, if the speed or acceleration of the steering angle of the wheel 12F as the steering wheel is reduced, the centrifugal force can be suppressed and the vehicle body can be smoothly tilted inward in the turning direction, so that the stability of the vehicle body is maintained. be able to. However, in this case, since the motion performance of the vehicle 10 is lowered, the maneuverability is deteriorated and the crisis avoidance performance is also lowered.

  On the other hand, in the present embodiment, as described above, when the occupant starts to cut the steering wheel, or when the steering wheel is increased, the link mechanism 30 starts to tilt, or the tilt is increased. When the vehicle 10 starts turning, or when the yaw rate increases, the rotational drive device 51 is prevented from exhibiting the driving force. As a result, when the stability of the vehicle 10 is liable to decrease, the rotational drive device 51 does not exhibit the driving force, so that the stability of the vehicle 10 is maintained without sacrificing maneuverability and crisis avoidance performance. be able to. In addition, since the rotational drive device 51 does not exert a driving force, the vehicle body is easily inclined inward in the turning direction, and the turning performance is improved.

  Next, the configuration of the vehicle body tilt control system will be described.

  FIG. 4 is a block diagram showing the configuration of the vehicle body tilt control system in the embodiment of the present invention.

  In the example shown in the figure, 46 is a tilt control ECU as a tilt control device, and includes a link angle sensor 25a, a first lateral acceleration sensor 44a, a second lateral acceleration sensor 44b, a roll rate sensor 44c, a yaw rate sensor 44d, and a vehicle speed sensor. 54 and the link motor 25. The tilt control ECU 46 includes a lateral acceleration calculation unit 48, a link angular velocity estimation unit 50, a disturbance calculation unit 43, a tilt control unit 47, and a link motor control unit 42.

  Reference numeral 61 denotes a steering control ECU as a steering control device, which is connected to a handle angle sensor 62, a steering angle sensor 63, a vehicle speed sensor 54, and a steering motor 65. Further, the steering control ECU 61 includes a steering control unit 66 and a steering motor control unit 67.

  Here, the lateral acceleration calculation unit 48 calculates a combined lateral acceleration based on the lateral acceleration detected by the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b. The link angular velocity estimation unit 50 calculates a link angular velocity prediction value based on the yaw rate as the yaw angular velocity detected by the yaw rate sensor 44d and the vehicle speed detected by the vehicle speed sensor 54. Further, the disturbance calculation unit 43 calculates a roll rate for the disturbance based on the roll rate as the angular velocity of the tilting motion of the vehicle body detected by the roll rate sensor 44c and the link angle detected by the link angle sensor 25a.

  The tilt controller 47 is based on the combined lateral acceleration calculated by the lateral acceleration calculator 48, the predicted link angular velocity calculated by the link angular velocity estimator 50, and the disturbance roll rate calculated by the disturbance calculator 43. Then, the speed command value as the control value is calculated and output. Further, the link motor control unit 42 is a control value for operating the link motor 25 based on the speed command value output from the tilt control unit 47 and the steering wheel steering angle command value output from the steering control unit 66. The torque command value is output.

  The steering control unit 66 calculates and outputs a steering wheel steering angle command value as a control value based on the steering wheel angle detected by the steering wheel angle sensor 62 and the vehicle speed detected by the vehicle speed sensor 54. The steering motor control unit 67 is a control pulse as a control value for operating the steering motor 65 based on the steering angle detected by the steering angle sensor 63 and the steering wheel steering angle command value output by the steering control unit 66. Is output.

  Next, the operation of the vehicle 10 configured as described above will be described. First, the operation of the lateral acceleration calculation process, which is a part of the operation of the vehicle body tilt control process in turning, will be described.

  FIG. 5 is a block diagram of the control system in the embodiment of the present invention, FIG. 6 is a diagram showing a dynamic model for explaining the leaning operation of the vehicle body during turning traveling in the embodiment of the present invention, and FIG. 7 is an embodiment of the present invention. It is a flowchart which shows the operation | movement of the lateral acceleration calculation process in the form.

  In the vehicle body tilt control process according to the present embodiment, control in which tilt control by the tilt control ECU 46 and steering control by the steering control ECU 61 are combined as shown in FIG. 4 is performed. Note that the tilt control by the tilt control ECU 46 is a combination of feedback control and feedforward control.

In FIG. 5, f ₁ is a transfer function represented by the equation (6) described later, G _P , G _RP , G _YD and G _SL are control gains for proportional control operation, and LPF is a low-pass filter. , S is a differential element. Further, f ₂ is a link angular velocity prediction value expressed by the following formula (10), and f ₃ is a roll rate gain.

  When turning is started, the vehicle body tilt control system starts the vehicle body tilt control process. By performing posture control, the vehicle 10 turns with the link mechanism 30 in a state where the vehicle body is tilted inward (right side in the drawing) as shown in FIG. Further, during turning, a centrifugal force to the outside of the turning acts on the vehicle body, and a lateral component of gravity is generated by tilting the vehicle body to the inside of the turn. Then, the lateral acceleration calculation unit 48 executes a lateral acceleration calculation process, calculates a combined lateral acceleration a, and outputs it to the tilt control unit 47. Then, the inclination control unit 47 performs feedback control, and outputs a speed command value as a control value such that the value of the combined lateral acceleration a becomes zero. Then, the link motor control unit 42 outputs a torque command value to the link motor 25 based on the speed command value output from the inclination control unit 47.

The vehicle body tilt control process is a process that is repeatedly executed by the vehicle body tilt control system at a predetermined control cycle T _S (for example, 5 [ms]) while the vehicle 10 is turned on. This is a process for improving turning performance and ensuring passenger comfort.

  In FIG. 6, 44A is a first sensor position indicating the position where the first lateral acceleration sensor 44a is disposed on the vehicle body, and 44B is a first position indicating the position where the second lateral acceleration sensor 44b is disposed on the vehicle body. Two sensor positions.

The acceleration detected by the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b and outputting the detected value is <1> centrifugal force acting on the vehicle body when turning, and <2> tilting the vehicle body toward the inside of the turn. The lateral component of the generated gravity, <3> the first lateral acceleration sensor 44a and the like due to the inclination of the vehicle body, the displacement of the backlash and the spring, etc., when only one of the left and right wheels 12L and 12R falls into the depression of the road surface The acceleration generated by the displacement of the second lateral acceleration sensor 44b in the circumferential direction, and the <4> operation of the link motor 25 or the reaction thereof causes the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b to be displaced in the circumferential direction. It is considered that there are four accelerations caused by this. Of these four acceleration, the <1> and <2>, the height of the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b, that is, independent of L ₁ and L _2. On the other hand, since <3> and <4> are accelerations generated by displacement in the circumferential direction, they are proportional to the distance from the roll center, that is, roughly proportional to L ₁ and L ₂ .

Here, the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44a and the second lateral acceleration sensor 44b detect and output the detected value. The acceleration <3> is defined as a _X1 and a _X2, and the first lateral acceleration sensor 44a and the second lateral acceleration. The acceleration of <4>, which is detected by the sensor 44b and outputs the detected value, is a _M1 and a _M2 . Further, the acceleration of <1> to the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b outputs the detected value detected by the a _T, a first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b is detected Then, the acceleration of <2> that outputs the detected value is defined as a _G. Since <1> and <2> are irrelevant to the heights of the first and second lateral acceleration sensors 44a and 44b, the detection values of the first and second lateral acceleration sensors 44a and 44b are equal. .

Then, only one of the left and right wheels 12L and 12R are inclined in the vehicle body due to the fall in a recess of a road surface 18, the angular velocity omega _R the circumferential direction of displacement by the displacement or the like of Gataya spring, the angular acceleration omega _{Let R} '. Further, the angular velocity of the circumferential displacement due to the operation of the link motor 25 or its reaction is ω _M , and the angular acceleration is ω _M ′. The angular velocity ω _M or the angular acceleration ω _M ′ can be obtained from the detection value of the link angle sensor 25a.

Then, a _X1 = L ₁ ω _R ′, a _X2 = L ₂ ω _R ′, a _M1 = L ₁ ω _M ′, a _M2 = L ₂ ω _M ′.

Further, when the detection value of the acceleration by the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b is detecting and outputting the a ₁ and a _2, a ₁ and a _2, four acceleration <1> to <4 It is represented by the following formulas (1) and (2).
_{a 1 = a T + a G} + L 1 ω R '+ L 1 ω M' ··· formula (1)
_{a 2 = a T + a G} + L 2 ω R '+ L 2 ω M' ··· formula (2)
Then, by subtracting equation (2) from equation (1), the following equation (3) can be obtained.
a ₁ −a ₂ = (L ₁ −L ₂ ) ω _R ′ + (L ₁ −L ₂ ) ω _M ′ Equation (3)
Here, the values of L ₁ and L ₂ are known because they are the heights of the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b. The value of ω _M ′ is known because it is a differential value of the angular velocity ω _M of the link motor 25. Then, on the right side of the equation (3), only the value of ω _R ′ of the first term is unknown, and all other values are known. Therefore, the value of ω _R ′ can be obtained from the detection values a ₁ and a _{2 of} the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b. That is, unnecessary acceleration components can be removed based on the detection values a ₁ and a ₂ of the first lateral acceleration sensor 44a and the second lateral acceleration sensor 44b.

When the vehicle body tilt control system starts the vehicle body tilt control process, the lateral acceleration calculation unit 48 starts the lateral acceleration calculation process, and first acquires the first lateral acceleration sensor value a ₁ (step S1) and the second lateral acceleration calculation process. An acceleration sensor value a ₂ is acquired (step S2). Then, the lateral acceleration calculation unit 48 calculates the acceleration difference Δa (step S3). The Δa is expressed by the following equation (4).
Δa = a ₁ −a ₂ Formula (4)
Then, the lateral acceleration calculation unit 48 performs ΔL call (step S4), and performs the L ₂ call (step S5). The ΔL is expressed by the following equation (5).
ΔL = L ₁ −L ₂ Formula (5)
Subsequently, the lateral acceleration calculation unit 48 calculates a combined lateral acceleration a (step S6). Incidentally, the synthetic lateral acceleration a lateral acceleration sensor 44 is a value corresponding to the lateral acceleration sensor value a when the one, first lateral acceleration sensor value a ₁ and the second lateral acceleration sensor value a ₂ Is obtained by the following equations (6) and (7).
a = a ₂ − (L ₂ / ΔL) Δa (6)
a = a ₁ − (L ₁ / ΔL) Δa (7)
Theoretically, the same value can be obtained by both equation (6) and equation (7), but since the acceleration caused by the circumferential displacement is proportional to the distance from the roll center, in practice, the roll center It is desirable to use a ₂ which is a detection value of the lateral acceleration sensor 44 closer to the second lateral acceleration sensor 44b as a reference. Therefore, in the present embodiment, the combined lateral acceleration a is calculated by Expression (6).

  Finally, the lateral acceleration calculation unit 48 sends the combined lateral acceleration a to the tilt control unit 47 (step S7), and ends the lateral acceleration calculation process.

Thus, in this embodiment, a first lateral acceleration sensor 44a and a second lateral acceleration sensor 44b is placed in different height positions, a first lateral acceleration sensor value a ₁ and the second lateral acceleration sensor A combined lateral acceleration a obtained by combining the value a ₂ is calculated, and feedback control is performed so that the value of the combined lateral acceleration a becomes zero to control the tilt angle of the vehicle body.

  As a result, unnecessary acceleration components can be removed, so that it is not affected by road surface conditions, the occurrence of vibrations and divergence of the control system can be prevented, and the control gain of the vehicle body tilt control system is increased. Control responsiveness can be improved.

  In the present embodiment, the case where there are two lateral acceleration sensors 44 has been described. However, if there are a plurality of lateral acceleration sensors 44 arranged at different heights, the number of lateral acceleration sensors 44 is three or more. There may be any number.

  Next, the operation of the link angular velocity estimation process for estimating the link angular velocity in turning travel will be described.

  FIG. 8 is a flowchart showing the operation of link angular velocity estimation processing in the embodiment of the present invention, FIG. 9 is a flowchart showing a subroutine of yaw rate differentiation processing in the embodiment of the present invention, and FIG. 10 is in the embodiment of the present invention. It is a flowchart which shows the subroutine of a filter process.

  When the link angular velocity estimation unit 50 starts the link angular velocity estimation process, the link angular velocity estimation unit 50 first acquires a yaw rate sensor value ψ that is a yaw rate value detected by the yaw rate sensor 44d (step S11), and a vehicle speed value detected by the vehicle speed sensor 54. The vehicle speed sensor value ν is obtained (step S12).

  Then, the link angular velocity estimation unit 50 performs yaw rate differentiation processing (step S13) and calculates Δψ. The Δψ is a value obtained by differentiating the yaw rate with time, and corresponds to the yaw angular acceleration.

In the yaw rate differentiation process, the link angular velocity estimation unit 50 first makes a ψ _old call (step S13-1). Note that ψ _old is the value of ψ (t) saved when the previous vehicle body tilt control process was executed. In the initial setting, ψ _old = 0.

Subsequently, the link angular velocity estimation unit 50 acquires a control cycle T _S (step S13-2).

Subsequently, the link angular velocity estimation unit 50 calculates the yaw rate differential value Δψ (step S13-3). Δψ is calculated by the following equation (8).
Δψ = (ψ (t) −ψ _old ) / T _S (8)
The link angular velocity estimation unit 50 stores ψ _old = ψ (t) (step S13-4), and ends the yaw rate differentiation process.

  Subsequently, the link angular velocity estimation unit 50 performs a filtering process on the yaw rate differential value Δψ (step S14).

In the filter processing, the link angular velocity estimation unit 50 first acquires a control cycle T _S (step S14-1).

  Subsequently, the link angular velocity estimation unit 50 acquires a cutoff frequency w (step S14-2).

Subsequently, the link angular velocity estimation unit 50 performs a Δψ _old call (step S14-3). Note that Δψ _old is a value of Δψ (t) saved when the previous vehicle body tilt control process was executed.

Subsequently, the link angular velocity estimation unit 50 calculates the filtered yaw rate differential value Δψ (t) (step S14-4). Δψ (t) is calculated by the following equation (9).
_{Δψ (t) = Δψ old /} (1 + T S w) + T S wψ / (1 + T S w) ··· (9)
The expression (9) is an expression of an IIR (Infinite Impulse Response) filter generally used as a bandpass filter, but a first-order lag low-pass filter may be simply used. As the IIR filter, for example, a Chebyshev type II filter may be used, or another filter may be used. Further, a generally used FIR (Finite Impulse Response) filter may be used. Furthermore, the cut-off frequency (−3 [dB] frequency) of the band pass filter is preferably 10 [Hz] or less, and more preferably several [Hz].

Then, the link angular velocity estimation unit 50 stores it as Δψ _old = Δψ (t) (step S14-5), and ends the filter process. That is, the value of Δψ (t) calculated at the time of execution of the current vehicle body tilt control process is stored in the storage unit as Δψ _old .

Subsequently, the link angular velocity estimation unit 50 calculates a link angular velocity prediction value f ₂ (step S15). Here, assuming that gravity is g, the link angular velocity predicted value f ₂ is calculated by the following equation (10).
f ₂ = dη / dt = (ν / g) (dψ / dt) (10)
As described above, the link angle sensor 25a detects a change in the angle of the upper horizontal link unit 31U with respect to the central vertical member 21, that is, a change in the link angle. Here, assuming that the link angle is η and the inclination angle of the vehicle body at the time of turning is controlled so that the centrifugal force a ₀ as the lateral acceleration and the gravity g are balanced, if the road surface 18 is horizontal, The relationship represented by the following formula (11) is established between the centrifugal force a ₀ and the gravity g.
a ₀ cos η = gsin η (11)
From the equation (11), the following equation (12) is derived.
a ₀ / g = sin η / cos η = tan η (12)
Further, the following equation (13) is derived from the equation (12).
a ₀ = g tan η (13)
On the other hand, assuming that the yaw rate sensor value, that is, the yaw rate is ψ, and the turning radius is r, the vehicle speed sensor value, that is, the vehicle speed ν and the centrifugal force a ₀ as the lateral acceleration acting on the vehicle body at the time of turning are It is represented by (14) and (15).
ν = rψ Equation (14)
a ₀ = rψ ² = νψ (15)
Then, the following equation (16) is derived from the equation (15) and the equation (13).
tan η = νψ / g (16)
Furthermore, it can be approximated as tan η≈η, and the change in the vehicle speed ν is sufficiently slow compared to the change in the link angle η, so that the vehicle speed ν can be regarded as a constant. From the above, the formula (10) can be obtained.

Subsequently, the link angular velocity estimation unit 50 calculates a link angular velocity control value a _f (step S16). The link angular velocity control value _af is calculated by the following equation (17).
a _f = Adη / dt (17)
Here, A is an arbitrary value of 0 to 1, and is a tuning constant determined according to the structure of the vehicle 10.

Finally, the link angular velocity estimation unit 50 sends the link angular velocity control value a _f to the inclination control unit 47 (step S17), and ends the link angular velocity estimation process.

  Next, the operation of the inclination control process for outputting the speed command value to the link motor control unit 42 will be described.

  FIG. 11 is a flowchart showing the operation of the tilt control process in the embodiment of the present invention.

  In the tilt control process, the tilt control unit 47 first receives the combined lateral acceleration a from the lateral acceleration calculation unit 48 (step S21).

Subsequently, the inclination control unit 47 makes an _old call (step S22). a _old is the combined lateral acceleration a stored when the vehicle body tilt control process is executed last time. In the initial setting, a _old = 0.

Subsequently, the inclination control unit 47 acquires the control cycle T _S (step S23), and calculates the differential value of a (step S24). Here, when the differential value of a is da / dt, the da / dt is calculated by the following equation (18).
da / dt = (a−a _old ) / T _S (18)
And the inclination control part 47 is preserve | saved as _aold = a (step S25). That is, the lateral acceleration sensor value a acquired at the time of execution of the current vehicle body tilt control process is stored as a _old in the storage unit.

Then, tilt control unit 47 calculates the first control value U _P (step S26). Here, if the control gain of the proportional control operation, that is, the proportional gain is _GP , the first control value _UP is calculated by the following equation (19).
U _P = G _P a ··· (19)
Then, tilt control unit 47 calculates the second control value U _D (step S27). Here, if the control gain of the differential control operation, that is, the differential time is G _D , the second control value U _D is calculated by the following equation (20).
U _D = G _D da / dt (20)
Subsequently, the inclination control unit 47 calculates a third control value U (step S28). Third control value U is the sum of the first control value U _P and the second control value U _D, is calculated by the following equation (21).
U = U _P + U _D ··· formula (21)
When the third control value U is calculated, the inclination control unit 47 receives the link angular velocity control value a _f from the link angular velocity estimation unit 50 (step S29).

Subsequently, the inclination control unit 47 calculates a fourth control value U (step S30). The fourth control value U is the sum of the third control value U and the link angular velocity control value _af, and is calculated by the following equation (22).
U = U + a _f Expression (22)
Finally, the tilt control unit 47 outputs the fourth control value U as a speed command value to the link motor control unit 42 (step S31), and ends the tilt control process.

  Next, the operation of the steering control process, which is a part of the vehicle body control operation in turning, will be described.

  FIG. 12 is a flowchart showing the operation of the steering control process in the embodiment of the present invention.

  In the steering control process, after obtaining the steering wheel angle δ, a function may be applied according to the vehicle speed ν. For example, in general, when the vehicle speed ν increases, it is not necessary to increase the steering angle of the steered wheels even when the steering wheel is largely turned. Therefore, the steering wheel angle δ used for the calculation in the steering control process can be determined by multiplying a function that is inversely proportional to the vehicle speed ν after being acquired from the steering wheel angle sensor 62.

  Further, the yaw rate of the vehicle body can be determined by the steering wheel angle δ. This constitutes feedback control so that a certain yaw rate is obtained at a certain steering angle δ regardless of the vehicle speed ν.

  These are all techniques employed when performing steer-by-wire.

  When the steering control process starts in the present embodiment, the steering control unit 66 first acquires a handle angle sensor value δ that is a value of the handle angle detected by the handle angle sensor 62 (step S41). The steering wheel angle is a steering angle command value input by an occupant operating the steering bar 41a.

Subsequently, the steering control unit 66 performs a filter process on the steering wheel angle sensor value δ (step S42). The filter process is a process using a low-pass filter similar to the filter process in the link angular velocity estimation process, and an IIR filter or FIR filter generally used as a band-pass filter can be used. A simple low-pass filter may be used. The filtered steering wheel angle sensor value δ is set as a steering angle target value δ ^* .

  Subsequently, the steering control unit 66 calculates a differential value dδ / dt of the steering wheel angle sensor value δ (step S43). Here, the steering wheel angle sensor value, that is, the differential value dδ / dt of the steering wheel angle δ represents the angular velocity of the steering wheel angle.

Subsequently, the steering control unit 66 calculates a second order differential value d ² δ / dt ² of the steering wheel angle sensor value δ (step S44). Here, the second-order differential value d ² δ / dt ² represents the angular acceleration of the steering wheel angle.

Then, the steering control unit 66 calculates the link angle correction value U _SL (step S45). Here, if the control gain for controlling the link angle according to the steering wheel angle, that is, the control gain for controlling the link angle so as to incline the vehicle body in the turning direction according to the direction in which the steering wheel is turned, is G _SL. The correction value _USL is calculated by the following equation (23).
U _SL = G _SL d ² δ / dt ² Formula (23)
Subsequently, the steering control unit 66 outputs the steering angle target value δ ^* to the steering motor control unit 67 (step S46).

Finally, the steering control unit 66 outputs the calculated link angle correction value _USL to the link motor control unit 42 (step S47), and ends the steering control process.

  Next, the operation of the link motor control process for outputting a torque command value to the link motor 25 will be described.

  FIG. 13 is a flowchart showing the operation of the link motor control process in the embodiment of the present invention.

  In the link motor control process, the link motor control unit 42 first receives the fourth control value U from the inclination control unit 47 (step S51).

Subsequently, the link motor control unit 42 receives a link angle correction value U _SL from the steering control unit 66 (step S52).

Subsequently, the link motor control unit 42 calculates a fifth control value U (step S53). The fifth control value U is calculated by the following equation (24) based on the fourth control value U and the link angle correction value U _SL .
U = U + U _SL (24)
Subsequently, the link motor control unit 42 acquires the angular velocity of the link angle, that is, the link angular velocity Δη (step S54). The link angular velocity Δη is calculated by acquiring the link angle η detected by the link angle sensor 25a and differentiating the link angle η with time. Further, the link motor control unit 42 can also acquire the value of the link angular velocity Δη from the disturbance calculation unit 43.

Subsequently, the link motor control unit 42 calculates a deviation as a control error (step S55). Here, when the deviation is ε, the ε is calculated by the following equation (25).
ε = U−Δη Formula (25)
U is the fifth control value U.

Subsequently, the link motor control unit 42 calculates a link motor control value as a torque command value for operating the link motor 25 (step S56). Here, when the link motor control value is U _M , the U _M is calculated by the following equation (26).
U _M = G _MP ε (26)
Note that _GMP is a motor control proportional gain, and the value of _{GMP is} a value set based on experiments or the like, and is stored in the storage means in advance.

Finally, the link motor control unit 42 outputs the link motor control value _UM to the link motor 25 (step S57), and ends the link motor control process.

  Although the link motor control process has been described here as proportional control, that is, P control, it may be PID control.

  Next, an operation for limiting a driving force generation command that is performed during the vehicle body tilt control process in turning traveling will be described.

  FIG. 14 is a block diagram of a control system for limiting a driving force generation command according to the embodiment of the present invention.

  In the vehicle body tilt control process in the present embodiment, control as shown in FIG. 14 is performed in order to limit the driving force generation command. The control shown in the figure is a control for limiting the driving force generation command under a predetermined condition during the vehicle body tilt control process.

Specifically, when at least one of the steering wheel angle δ, the link angle η, and the yaw rate ψ has the same sign as the differential value and the absolute value is equal to or greater than the threshold value, regardless of the value of the throttle opening th. The throttle opening target value th ^* is controlled to be zero.

In the figure, s is a differential element, and f ₄ is a transfer function represented by the following equation (27).

  Here, the value of δ is zero when the vehicle 10 goes straight, becomes positive when the vehicle 10 is steered to turn right, and becomes minus when the vehicle 10 is steered to turn left. Further, the value of η is zero when the vehicle 10 is standing upright, becomes positive when the link motor 25 of the link mechanism 30 is operated so as to incline in the right direction, and links so that it inclines in the left direction. It becomes negative when the motor 25 is activated. Further, the value of ψ is zero when the vehicle 10 goes straight, becomes positive when turning right, and becomes negative when turning left.

  Note that S, L, and Y are typically all zero, that is, S = L = Y = 0, but it can be said that the signs of the values of δ, η, and ψ are determined to be positive or negative. May be set for each. Further, dS, dL, and dY are desirably arbitrary values that can be said to be positive or negative in the sign of each differential value of δ, η, and ψ. Accordingly, a dead band having a certain width can be set in the vicinity of zero in the values of δ, η, and ψ and the differential values of δ, η, and ψ, and the control is stabilized.

G is a control gain of proportional operation expressed by the following equation (28).
G = G _sth × G _lth × G _yth (28)
Therefore, the throttle opening target value th ^* is expressed by the following equation (29).
th ^* = Gth (29)
As can be seen from the equations (27) to (29), when at least one of the handle angle δ, the link angle η, and the yaw rate ψ increases in the plus or minus direction, G _sth , G _lth or G _yth becomes Since it becomes zero, the throttle opening target value th ^* becomes zero. That is, when the occupant starts turning the steering wheel, or when the steering wheel is turned up, when the link mechanism 30 starts to tilt, when the tilting increases, when the vehicle 10 starts turning, or When the stability of the vehicle body tends to decrease, such as when the yaw rate increases, the throttle opening target value th ^* is set to zero to limit the drive force generation command for operating the rotary drive device 51. Therefore, the stability of the vehicle body can be reliably maintained even during turning. Furthermore, since the rotational drive device 51 does not exhibit a driving force during turning, the vehicle body easily tilts inward in the turning direction, so that the turning performance is improved.

  Further, when the steering wheel angle δ, the link angle η, and the yaw rate ψ are all not increased, the vehicle body becomes stable, and thus the limitation on the acceleration command value is released.

  Thus, in the present embodiment, the driving force generation command is limited when the cornering is started. That is, when a change in at least one of the steering wheel angle δ, the link angle η, and the yaw rate ψ as the steering amount of the steered wheel becomes greater than a predetermined value (S and dS, L and dL, and Y and dY) ( However, when S, L, Y, dS, dL, and dY are not zero, | δ |> | S | and | S ′ |> | dS |, | η |> | L | and | η ′ |> | DL | or | ψ |> | Y | and | ψ ′ |> | dY |), the driving force generation command is limited. As a result, when the stability of the vehicle body is likely to decrease, such as immediately after the start of turning, no driving force is applied to the left and right wheels 12L and 12R as drive wheels, so that the stability of the vehicle body can be reliably maintained. .

More specifically, when at least one of the steering wheel angle δ, the link angle η, and the yaw rate ψ has the same sign as its differential value, the throttle opening target value th ^* is zero regardless of the value of the throttle opening th ^. Control to be That is, when the occupant starts turning the steering wheel, or when the steering wheel is turned up, when the link mechanism 30 starts to tilt, when the tilting increases, when the vehicle 10 starts turning, or When the yaw rate increases, the rotational drive device 51 is prevented from exerting a driving force. As described above, when the stability of the vehicle body is likely to be reduced, the rotational driving device 51 does not exhibit the driving force, so that it is possible to reliably prevent the stability from being lowered. In addition, since the rotational drive device 51 does not exert a driving force, the vehicle body is easily inclined inward in the turning direction, and the turning performance is improved.

  Further, when the steering wheel angle δ, the link angle η, and the yaw rate ψ all do not increase, that is, when the steering wheel angle δ, the link angle η, and the yaw rate ψ all have signs different from the differential values, the driving force generation command Remove the restrictions. As described above, since the restriction on the driving force generation command is released while the vehicle body is stable, the vehicle body does not become unstable even if the rotational driving device 51 exerts the driving force.

  In the present embodiment, the steering motor 65 rotates the lower end of the steering shaft member based on the steering wheel angle detected by the steering wheel angle sensor 62, so that the wheel 12F as the steering wheel changes the steering angle. Although the case where a steering system called a so-called steer-by-wire is adopted has been described, the handlebar 41a and the lower end of the steering shaft member are mechanically connected to each other as in the case of a general motorcycle, bicycle, etc. It is also possible to change the steering angle of the wheel 12F directly by operating 41a. That is, it is not always necessary to employ a steering system called steer-by-wire.

  The present invention is not limited to the above-described embodiment, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

  The present invention can be used for a vehicle having at least a pair of left and right wheels.

DESCRIPTION OF SYMBOLS 10 Vehicle 11 Boarding part 12F, 12L, 12R Wheel 20 Main-body part 25 Link motor 35 Throttle grip 41a Handle bar 51L, 51R Rotation drive device 65 Steering motor

Claims (4)

A vehicle body including a steering unit and a main body unit coupled to each other;
A wheel rotatably attached to the steering unit, and a steerable steering wheel for steering the vehicle body;
Non-steering wheels that are rotatably attached to the main body and are not steerable;
A link mechanism for tilting the steering part or the main body part in a turning direction;
An inclination actuator device for operating the link mechanism;
A rotational drive device for applying a driving force to the steered wheel or the non-steered wheel;
A drive command device for inputting a drive force generation command;
A controller for controlling the tilting actuator device and the rotation driving device,
When the absolute value of a change in at least one of the steering amount of the steered wheel, the link angle of the link mechanism, and the yaw rate of the vehicle body is greater than a predetermined value, the control device issues the driving force generation command. Vehicle characterized by restriction.   The control device limits the driving force generation command when at least one of a steering amount of the steering wheel, a link angle of the link mechanism, and a yaw rate of the vehicle body has the same sign as a differential value thereof. Item 4. The vehicle according to Item 1.   The control device releases the restriction on the driving force generation command when all of the steering amount of the steered wheel, the link angle of the link mechanism, and the yaw rate of the vehicle body have signs different from the differential values. 2. The vehicle according to 2. A steering device for inputting steering command information;
A steering actuator device that changes a steering angle of the steered wheel based on steering command information input from the steering device;
The vehicle according to claim 1, wherein the control device controls the steering actuator device.

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