Vehicle

Abstract

A vehicle (100) is provided with a steering portion (22) disposed above a front wheel (1), a link portion (30) linked with a first member (20) that supports the front wheel (1) and enables the first member (20) to swing in a left-right direction about an axis extending in a front-rear direction with respect to a second member (12) that supports a rear wheel (2), an input portion (24) that inputs a travel command including an acceleration command, a control portion (40) that controls a travel actuator (4), a steering angle detection portion (42) that detects a steering angle of the steering portion (22) in the left-right direction, and a swing angle detection portion (43) that detects a swing angle of the first member (20) in the left-right direction. The control portion (40) controls the travel actuator (4) to generate a driving force lower than a driving force corresponding to the acceleration command based on the steering angle and the swing angle.

Description

Technical Field

[0001] This invention relates to a vehicle having front wheels and rear wheels. Background Technology

[0002] As such vehicles, there are previously known vehicles configured to swing in the left and right directions via a swing mechanism (see, for example, Patent Document 1). In the vehicle described in Patent Document 1, the front wheel is also configured to be able to turn left and right depending on the operation of the handlebars.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 6935610. Summary of the Invention

[0006] The problem the invention aims to solve

[0007] However, when turning and accelerating or decelerating in an inappropriate manner, the vehicle's posture may become unstable.

[0008] Solution for solving the problem

[0009] One technical solution of the present invention includes: a front wheel and a rear wheel; a steering unit disposed above the front wheel; a footrest for a passenger; a first member supporting the front wheel so as to be rotatable and capable of steering according to the steering unit; a second member disposed behind the first member and supporting the rear wheel so as to be rotatable; a connecting part connected to the connecting first member in such a way that the first member can swing in the left-right direction relative to the second member about an axis extending in the front-rear direction; a driving actuator driving at least one of the front wheel and the rear wheel; an input unit inputting a driving command including an acceleration command; a control unit controlling the driving actuator to generate a driving force corresponding to the driving command input by the input unit; a steering angle detection unit detecting the steering angle of the steering unit in the left-right direction; and a sway angle detection unit detecting the sway angle of the first member relative to the second member in the left-right direction. The control unit controls the driving actuator to generate a driving force lower than the driving force corresponding to the acceleration command input by the input unit based on the steering angle detected by the steering angle detection unit and the sway angle detected by the sway angle detection unit.

[0010] Invention Effects

[0011] By employing this invention, the effects of inappropriate maneuvers during steering can be suppressed, thereby improving vehicle stability. Attached Figure Description

[0012] Figure 1This is a perspective view showing the overall structure of a vehicle according to an embodiment of the present invention, viewed from the left oblique front.

[0013] Figure 2 This is a front view showing the overall structure of a vehicle according to an embodiment of the present invention.

[0014] Figure 3 This is a cross-sectional view showing a schematic structure of a Nedhart rubber spring installed at the connection part of a vehicle according to an embodiment of the present invention.

[0015] Figure 4 This is a block diagram illustrating the control structure of a vehicle's driving system according to an embodiment of the present invention.

[0016] Figure 5A It is shown in Figure 4 A graph showing the relationship between the steering angle, yaw angle, and first correction coefficient when the steering angle is above 0° in the calculation of motor command values.

[0017] Figure 5B It is shown in Figure 4 A graph showing the relationship between the steering angle, yaw angle, and first correction factor when the steering angle is below 0°, used in calculating motor command values.

[0018] Figure 6 It is shown in Figure 4 A graph showing the relationship between vehicle speed and the second correction coefficient used when calculating motor command values.

[0019] Figure 7 It is shown in Figure 4 A diagram illustrating how the correction factor used in calculating motor command values ​​changes with increasing vehicle speed.

[0020] Figure 8 This is a diagram illustrating an example of the sway angle of gravity relative to a baseline when a vehicle is on an incline. Detailed Implementation

[0021] The following is for reference Figures 1 to 8 Embodiments of the present invention will be described. The vehicle of an embodiment of the present invention is a three-wheeled vehicle having a single front wheel and a pair of left and right rear wheels, configured such that a user can ride in a standing position.

[0022] Figure 1 This is a perspective view showing the overall structure of the vehicle 100 according to an embodiment of the present invention. Figure 2 This is the front view. Below, as shown in the figure, the three orthogonal axial directions are defined as the front-rear direction (length direction), left-right direction (width direction), and up-down direction (height direction) of the vehicle 100, and the structure of each part is described according to this definition. Figure 1This is a picture of vehicle 100 viewed from the left diagonal front. Figure 2 This is a picture of vehicle 100 viewed from the front.

[0023] like Figure 1 , Figure 2 As shown, the vehicle 100 has front wheels 1 and rear wheels 2, and a frame FL constituting the frame of the vehicle 100, which is configured as a whole in a left-right symmetrical manner with reference to a centerline CL1 passing through the center of the vehicle 100 in the left-right direction. More specifically, the front wheels 1 are arranged along the centerline CL1, and the left and right rear wheels 2 are arranged in symmetrical positions with the centerline CL1 separated by the centerline CL1. The front wheels 1 and rear wheels 2 have the same diameter. It should be noted that the diameter of the front wheels 1 may be smaller or larger than that of the rear wheels 2. The centerline CL1 is the swing center of the connecting part 30 described later, and extends backward at a downward slope. It should be noted that the centerline CL1 may also extend backward horizontally or backward at an upward slope. The frame FL has a main frame 10 extending from the front wheels 1 to the rear wheels 2 and a longitudinal frame 20 erected above the front wheels 1.

[0024] The main frame 10 has a front frame 11 extending rearward from above the front wheel 1 and a rear frame 12 connected to the front frame 11 and extending to the rear wheel 2. The front frame 11 is configured to slope forward with an upward gradient (front higher than rear). The front end 11a of the front frame 11 is located above the front wheel 1, and the rear end 11b extends approximately horizontally.

[0025] The longitudinal frame 20 has a generally cylindrical or cylindrical shaft 21 extending rearward along an axis CL2 at a predetermined angle in the direction of gravity, with its upper end positioned further rearward than its lower end. The shaft 21 passes through the front end 11a of the front frame 11 and is rotatably supported on the front frame 11 about the axis CL2. A handlebar 22 is mounted on the upper end of the shaft 21, and a pair of left and right front forks 23 are fixed to the lower end. It should be noted that the longitudinal frame 20 can also be composed of a longitudinal tube extending upward from the front end 11a of the front frame 11 and a shaft passing through the interior of the longitudinal tube. In this case, the longitudinal tube is integrally formed with the front frame 11, and the shaft is configured to rotate within the longitudinal tube about the axis CL2.

[0026] The front wheel 1's rotation axle 1a is supported by a pair of left and right front forks 23, allowing it to rotate. The front wheel 1 is steered by rotating the handlebar 22 around the axis CL2. The handlebar 22 is a horizontal bar handlebar extending in a roughly straight line in the left-right direction, with resin or rubber handlebars 22a for the user to grip at both ends of the handlebar 22. A brake lever 22b is located in front of the handlebars 22a.

[0027] Although detailed illustrations are omitted, the drive motor 4 (hub motor) and braking unit 5 are housed inside the front wheel 1. For example, the drive motor 4 is positioned on the left side and the braking unit 5 on the right side. The vehicle 100 is configured as an electric vehicle driven by the drive motor 4. A throttle lever 24 is provided on or near the handlebar 22 or the handlebar 22a. The throttle lever 24 is configured to be operable by the occupant while holding the handlebar 22a, and the input of the throttle lever 24 includes a driving command, such as an acceleration command for the vehicle 100. The throttle lever 24 is configured to be adjustable in amount of operation, such that the greater the amount of operation input to the throttle lever 24, the greater the driving force of the drive motor 4.

[0028] The braking unit 5 is configured as, for example, a drum brake. It should be noted that the braking unit 5 is also provided on the rear wheel 2. These braking units 5 operate according to the operation of the brake operating lever 22b, applying braking force to the front wheel 1 and the rear wheel 2. It should be noted that the travel motor 4, which is an electric motor, may not be provided on the front wheel 1, but may be provided in the rear wheel 2 or both the front wheel 1 and the rear wheel 2. This improves the traction and climbing ability of the vehicle 100.

[0029] The elongated battery 6 is supported on the rear surface of the longitudinal frame 20 by a support member. The battery 6 is a secondary battery, such as a lithium-ion battery, that stores electricity supplied to the drive motor 4. The battery 6 is connected to the drive motor 4 via wires passing through the longitudinal frame 20. The power supplied from the battery 6 to the drive motor 4 is controlled by a power control unit (not shown). It should be noted that the battery 6 can also be disposed inside the longitudinal frame 20, or around other structural components such as the main frame 10.

[0030] Although the illustration is omitted, the handlebars 22 include a power switch that indicates the main power supply, a turn signal switch that indicates left or right turns, and an accelerator lever for inputting driving commands, all operable by the user. A display showing vehicle information such as remaining battery capacity and set speed can also be installed. Furthermore, although the illustration is omitted, a pair of left and right turn signals that flash according to the operation of the turn signal switch are located below the handlebars 22, and a headlight is located at the upper end of the longitudinal frame 20.

[0031] The rear frame 12 extends rearward through the inside of the left and right rear wheels 2. Although not shown in the figure, support frames (e.g., a pair of front and rear support frames) extending in the left and right directions are joined on the left and right sides of the rear frame 12 at a position in front of the rear wheels 2. A rear wheel support portion extending in the left and right directions is joined at the rear part (e.g., the rear end) of the rear frame 12, and the rear wheel support portion supports the rotation axle 2a of the rear wheel 2 so that it can rotate.

[0032] A roughly rectangular plate, or pedal, 25, is mounted on the upper surface of a pair of supporting frames. It extends longitudinally from the rear frame 12 to the left and right rear wheels 2, and laterally within the length between the left and right rear wheels 2. The pedal 25 is fixed to the supporting frames by welding or the like, and its longitudinal ends are supported by the rear frame 12 via the supporting frames. The pedal 25 serves as a footrest for a standing user (occupant), and its upper surface (placement surface) is a horizontal plane parallel to the road surface 101. The pedal 25's longitudinal length and lateral width are defined by a predetermined portion capable of supporting the user's foot, for example, from the heel to the ball of the big toe.

[0033] The front frame 11 and the rear frame 12 of the main frame 10 are connected by a connecting part 30. That is, the front frame 11 is connected to the rear frame 12 by the connecting part 30 in a manner that allows it to swing left and right about a centerline CL1 extending in the longitudinal direction. The connecting part 30 has a Nederhardt rubber spring 31 fixed to the bottom surface of the flat plate portion of the front frame 11.

[0034] Figure 3 This is a cross-sectional view showing the schematic structure of the Nedhart rubber spring 31 installed in the connecting part 30. (See attached image.) Figure 3 As shown, the Niedhart rubber spring 31 is housed within a generally rectangular frame-shaped housing 311 fixed to the rear end 11b of the front frame 11. A generally circular shaft 312 is disposed within the housing 311, fixed to the front end of the rear frame 12, and extends longitudinally along the centerline CL1. It should be noted that the front end of the rear frame 12 can also be configured to have a generally circular cross-section and used as the shaft 312. The Niedhart rubber spring 31 has a generally rhomboid cam block 313 splinedly engaged with the shaft 312 in a manner capable of rotating integrally with it, and rubber rollers 314 arranged opposite to the concave surfaces of the cam block 313.

[0035] Figure 3 This is the initial state of the front frame 11 without any swaying. At this point, as... Figure 2 As shown by the solid line, the longitudinal frame 20 does not tilt to the left or right, and the vehicle 100 is in a reference posture. When a torque is applied to the housing 311 from this initial state, causing the housing 311 to rotate about the axis CL1, the rubber roller 314 is pressed between the housing 311 and the cam block 313, resulting in elastic deformation, and the rubber roller 314 becomes elliptical. At this time, the front frame 11 and the longitudinal frame 20 swing together, and the vehicle 100 is in a reference posture. Figure 2The double-dotted line indicates that the vehicle is tilted. In this case, as the rotation angle of the housing 311 increases, the rotational resistance to the housing 311 increases. When the torque acting on the housing 311 becomes 0, the rubber roller 314 returns to its original shape by means of elasticity, and the front frame 11 returns to the reference position.

[0036] In this way, by configuring the front frame 11 of the main frame 10 to swing via the connecting part 30, the user of the vehicle 100, who is standing, can easily turn the vehicle 100 left and right. For example, when turning the vehicle 100 left and right, the user slightly bends their knees and ankles, tilting their upper body to the left and right. As a result, with the footrest 25, which is integrated with the rear frame 12, remaining horizontal, the user can maintain a stable posture with both feet on the footrest 25, causing the longitudinal frame 20 and the front frame 11 to swing together, tilting the front wheel 1 left and right. Consequently, the vehicle 100 can turn smoothly, improving its maneuverability.

[0037] Furthermore, by providing a Niedhart rubber spring 31 at the connecting part 30, a restoring force can be applied to the front frame 11 when it swings left and right from its reference posture, effectively suppressing the swaying of the front frame 11. It should be noted that the cam block 313 may not be a quadrilateral, but rather formed into other polygonal shapes (e.g., a triangle). It may not be that all surfaces of the cam block 313 are concave, but for example, two surfaces are concave, with the rubber roller 314 positioned facing these concave surfaces. As an example, it may also be positioned on two surfaces of a triangular cam block. The restoring force may also be applied to the front frame 11 using an elastic member such as a coil spring, rather than the Niedhart rubber spring 31. That is, the configuration of the restoring force application part is not limited to the Niedhart rubber spring 51.

[0038] Although the illustration is omitted, the center point of the load acting on the pedal 25 due to the user's weight in a standing position (the center point of the load acting from the soles of the feet) is located within a triangular area connecting the contact points of the front wheel 1 and the contact points of the left and right rear wheels 2 when viewed from above. Therefore, the user can ride in a stable posture in the vehicle 100, whether in motion or parked.

[0039] The longitudinal frame 20 is rotatably mounted at the rear via a rotating mechanism 201 located above the front end 11a of the front frame 11. Figure 1 (The direction of arrow A). This allows the vehicle to move 100 degrees from... Figure 1The vehicle's driving posture changes to a folded posture. In the folded posture, the longitudinal frame 20 and the rear frame 12 are arranged approximately parallel between the left and right rear wheels 2. By standing the folded vehicle 100 upright with the rear wheels 2 as a fulcrum and positioning the front wheels 1 on top to allow the rear wheels 2 to rotate, the vehicle 100 can be easily transported. It should be noted that a handle 14 for gripping when transporting the vehicle 100 is provided at the front end of the front frame 11.

[0040] However, in this embodiment, the handlebars 22 are configured to turn left and right around the axis CL2, and the longitudinal frame 20 is configured to swing left and right around the centerline CL1. Therefore, when the vehicle 100 starts or turns, if the throttle lever 24 is operated (throttle operation) when the relationship between the steering angle and the swing angle is inappropriate, the stability of the vehicle 100 may decrease. Specifically, when the handlebars 22 are turned to the left and the longitudinal frame 20 is swinging to the right, the change in centrifugal force of the vehicle 100 may increase when the throttle is operated, resulting in a decrease in the stability of the vehicle 100. Therefore, in order to suppress the decrease in the stability of the vehicle 100 when the relationship between the steering angle and the swing angle is inappropriate, this embodiment is configured as follows.

[0041] The following, such as Figure 1 As shown, the amount of operation of the handlebar 22 from the axis L1 extending in the longitudinal direction is defined as the steering angle θs. The steering angle θs when the handlebar 22 is operated to the left is defined as the positive steering angle, and the steering angle θs when the handlebar 22 is operated to the right is defined as the negative steering angle. Furthermore, as... Figure 2 As shown, the amount of sway of the longitudinal frame 20 from the axis L2 extending in the vertical direction is defined as the sway angle θr. The sway angle θr when the longitudinal frame 20 sways to the left is defined as the positive sway angle, and the sway angle θr when it sways to the right is defined as the negative sway angle.

[0042] Figure 4 This is a block diagram schematically showing the structure of the controller 40 installed in the power control unit that controls the drive of the driving motor 4. The controller 40 is configured as a computer, including an arithmetic unit such as a CPU (Central Processing Unit), a storage unit such as ROM (Read-Only Memory) and RAM (Random Access Memory), and other peripheral circuits. Figure 4 As shown, the controller 40 receives signals from the throttle sensor 41, the steering angle sensor 42, the yaw angle sensor 43, and the vehicle speed sensor 44.

[0043] Throttle sensor 41 is mounted on throttle lever 24 and detects the command value (throttle command value Th) corresponding to the amount of operation of throttle lever 24. Steering angle sensor 42 is mounted on, for example, shaft 21 and detects the amount of rotation of shaft 21 according to the operation of handlebar 22, i.e., detects steering angle θs. Sway angle sensor 43 is mounted on connecting part 30 and detects sway angle θr. Vehicle speed sensor 44 is mounted on the rotating shaft 1a of front wheel 1 or the drive motor 4 and detects vehicle speed v based on the rotational speed of rotating shaft 1a or drive motor 4.

[0044] The controller 40 performs prescribed processing based on the input signals from the sensors 41-44 to control the drive of the travel motor 4. The travel motor 4 is, for example, an embedded magnet type synchronous motor having a rotor and a stator arranged around the rotor, and is driven by power supplied from the battery 6 to the coils of the stator through the controller 40. It should be noted that synchronous reluctance motors without magnets, switched reluctance motors, etc., can also be used as the travel motor 4.

[0045] The controller 40 calculates a correction coefficient γ for correcting the throttle command value Th based on the steering angle θs, yaw angle θr, and vehicle speed v detected by sensors 42-44. Specifically, the calculation unit 40A calculates a first correction coefficient α using a function f(θs,θr) with the steering angle θs and yaw angle θr as parameters, and the calculation unit 40B calculates a second correction coefficient β using a function g(v) with the vehicle speed v as a parameter. Further, the calculation unit 40C calculates α raised to the power of β as the correction coefficient γ. Further, the calculation unit 40C multiplies the correction coefficient γ by the throttle command value Th to obtain a corrected throttle command value Th' (called the motor command value), and outputs it to the motor output unit 40D. The motor output unit 40D controls the drive motor 4 to output a drive torque corresponding to the motor command value Th'.

[0046] Figure 5A , Figure 5B This is a diagram illustrating an example of the characteristics representing the relationship between the steering angle θs, the yaw angle θr, and the first correction factor α. In particular, Figure 5A This refers to the characteristics when the steering angle θs is above 0° (when turning to the left). Figure 5B This refers to the characteristics when the steering angle θs is below 0° (when turning to the right). Specifically, Figure 5A The characteristics f10 (solid line), f11 (dashed line), f12 (single-dot dashed line), and f13 (double-dot dashed line) represent the relationship between the sway angle θr and α when the steering angle θs is 0°, 10°, 20°, and 30°, respectively. Figure 5BThe characteristics f20 (solid line), f21 (dashed line), f22 (single-dot dashed line), and f23 (double-dot dashed line) represent the relationship between the yaw angle θr and α when the steering angle θs is 0°, -10°, -20°, and -30°, respectively. These characteristics are pre-stored in memory.

[0047] The first correction coefficient α is calculated within the range of greater than 0 and less than 1. The larger the first correction coefficient α, the larger the correction coefficient γ and the motor command value Th'. For example Figure 5A , Figure 5B As shown, when the steering angle θs is 0° (characteristics f10, f20), in the region where the sway angle θr is small, α is 1 or approximately 1. As the magnitude (absolute value) of the sway angle θr increases, α gradually decreases. Therefore, when the magnitude of the sway angle θr reaches or exceeds a specified value, the motor command value Th' decreases, and the motor output is suppressed.

[0048] When the signs of the steering angle θs and the yaw angle θr are the same, that is... Figure 5A When the swing angle θr is positive, in Figure 5B When the sway angle θr is negative, characteristics f11~f13 and f21~f23 are the same as characteristics f10 and f20. In the region where the sway angle θr is small, α is approximately constant, and α gradually decreases as the magnitude of the sway angle θr increases. However, when comparing with the same sway angle θr, α decreases as the steering angle θs increases. In other words, the rate of decrease of α increases with the increase of the steering angle θs. As a result, as the magnitude of the steering angle θs increases, the correction coefficient γ and the motor command value Th' decrease, and the motor output is suppressed.

[0049] On the other hand, when the signs of the steering angle θs and the yaw angle θr are different from each other, that is... Figure 5A When the swing angle θr is negative, in Figure 5B When the sway angle θr is positive, the characteristics f11~f13 and f21~f23 also show almost no fixed range for α as the magnitude of the sway angle θr increases. For example, α decreases sharply along a curve approximated by a convex parabola or an inverse proportional curve. This rate of decrease is greater than the rate of decrease when the signs of the steering angle θs and the sway angle θr are the same. It should be noted that when comparing with the same sway angle θr, α decreases as the steering angle θs increases. Thus, when the signs of the steering angle θs and the sway angle θr are different, α decreases sharply as the magnitude of the sway angle θr increases. Therefore, compared with when the signs of the steering angle θs and the sway angle θr are the same, the motor output is suppressed to a greater extent.

[0050] Figure 6 This is a graph illustrating an example of the characteristic representing the relationship between vehicle speed v and the second correction coefficient β. This characteristic is pre-stored in memory. The second correction coefficient β is set in the range of 0 to 1. Figure 6 As shown, the second correction coefficient β is 1 or approximately 1 in the region of low vehicle speed v, and gradually decreases as vehicle speed v increases. More specifically, β is approximately constant in the region of low vehicle speed v, but decreases sharply as vehicle speed v increases when it reaches a specified value or higher.

[0051] Figure 7 This is a diagram illustrating an example of the relationship between the sway angle θr, vehicle speed v, and correction factor γ (=α^β) when the steering angle θs is a specified angle (e.g., -30°). Figure 7 The characteristics h0 (solid line), h1 (dashed line), h2 (single-dot dashed line), and h3 (double-dot dashed line) represent the relationship between the sway angle and γ at vehicle speeds of 0 km / h, 10 km / h, 20 km / h, and 25 km / h, respectively. This characteristic is derived from the characteristics of the first correction coefficient α. Figure 5A , Figure 5B ) and the characteristics of the second correction coefficient β Figure 6 ) obtained. For example Figure 7 As shown, the correction coefficient γ increases with increasing vehicle speed v. Therefore, with increasing vehicle speed v, the motor command value Th' increases, and the degree of suppression of motor output decreases.

[0052] In this implementation, when the steering direction of the handlebars 22 and the swing direction of the longitudinal frame 20 are different, compared to when the steering direction and swing direction are the same, the motor command value Th' when the throttle lever 24 is operated is smaller, and the motor output is suppressed. For example, if a sudden throttle operation is performed while the handlebars 22 is turning to the left and the longitudinal frame 20 is swinging to the right, the motor output is suppressed. As a result, the change in centrifugal force of the vehicle 100 is reduced, preventing a decrease in the stability of the vehicle 100.

[0053] Furthermore, as the vehicle speed v increases, the degree of suppression of motor output decreases, allowing the user to accelerate the vehicle 100 without any noticeable discomfort. That is, as the vehicle speed v increases, the change in vehicle speed v relative to the change in the throttle command value Th decreases. Therefore, when motor output is suppressed, the vehicle speed is difficult to increase even when the user is operating the throttle, which can easily cause a feeling of discomfort for the user. In this respect, because the suppression rate of motor output decreases as the vehicle speed v increases in this embodiment, the user's discomfort can be reduced. It should be noted that when the vehicle speed v is high, the change in centrifugal force when operating the throttle lever 24 is small. Therefore, even if the degree of suppression of motor output decreases, the impact on the stability of the vehicle 100 is small and will not be a problem.

[0054] The following effects can be achieved by adopting this implementation method.

[0055] (1) The vehicle 100 of this embodiment includes: a front wheel 1 and a rear wheel 2; a handlebar 22 disposed above the front wheel 1; a footrest 25 for a passenger (user) to place their feet; a front frame 11 and a longitudinal frame 20, which support the front wheel 1 so that it can rotate and can be steered according to the handlebar 22; a rear frame 12 disposed behind the front frame 11 and supporting the rear wheel 2 so that it can rotate; and a connecting part 30, which allows the front frame 11 and the longitudinal frame 20 to be aligned with the rear frame 12 with a centerline CL1 extending in the longitudinal direction. The center of gravity swings left and right, connected to the front frame 11 and the longitudinal frame 20; a travel motor 4 drives the front wheel 1; a throttle lever 24 receives driving commands, including acceleration commands, from the occupant's input; a controller 40 controls the travel motor 4 to generate driving force corresponding to the driving command (throttle command value Th) input from the throttle lever 24; a steering angle sensor 42 detects the left and right steering angle θs of the handlebars 22; and a sway angle sensor 43 detects the left and right sway angle θr of the longitudinal frame 20. Figure 1 , 4 The controller 40, based on the steering angle θs detected by the steering angle sensor 42 and the sway angle θr detected by the sway angle sensor 43, controls the drive motor 4 to generate a driving force lower than the driving force corresponding to the throttle command value Th input through the throttle lever 24. Figure 4 ).

[0056] With this structure, in a vehicle 100 where the longitudinal frame 20 can swing and the front wheels 1 can steer, when the throttle lever 24 is suddenly operated while the swing direction and steering direction are inconsistent, such as during a turn, the centrifugal force is suppressed from changing significantly with the increase or decrease of vehicle speed. As a result, inappropriate acceleration and deceleration operations with inappropriate relationships between vehicle speed, steering angle, and swing angle can be suppressed, and the posture of the vehicle 100 can be prevented from becoming unstable.

[0057] (2) When the steering direction of the handlebars 22 and the swing direction of the longitudinal frame 20, determined by the values ​​detected by the steering angle sensor 42 and the swing angle sensor 43, are not in the same direction, the controller 40 controls the travel motor 4, so that the driving force for the same acceleration command is reduced compared to when the steering direction and the swing direction are in the same direction. Figure 5A , Figure 5B Therefore, when the throttle is operated, for example, with the handlebars 22 turning to the left and the longitudinal frame 20 swinging to the right, the increase or decrease in vehicle speed is suppressed, so the change in centrifugal force is small, and the vehicle's posture can be prevented from becoming unstable.

[0058] (3) The larger the steering angle θs detected by the steering angle sensor 42, the greater the rate of reduction of the driving force of the controller 40 in response to the throttle command value Th. Figure 5A , Figure 5BThe larger the steering angle θs, the more unstable the vehicle posture becomes relative to the increase or decrease of vehicle speed. However, by suppressing the motor output to a greater extent, the vehicle posture can be stabilized when the steering angle θs is large.

[0059] (4) The vehicle 100 is also equipped with a vehicle speed sensor 44 for detecting vehicle speed v. Figure 4 The controller 40 also controls the drive motor 4 to generate a driving force lower than the driving force corresponding to the acceleration command input from the throttle lever 24, based on the vehicle speed v detected by the vehicle speed sensor 44, i.e., controls the motor output ( Figure 4 , Figure 6 In this way, the vehicle speed v is also taken into account when controlling the driving motor 4 in addition to the steering angle θs and yaw angle θr, thereby properly preventing the vehicle posture from becoming unstable when the throttle lever 24 is suddenly operated.

[0060] (5) The slower the vehicle speed v detected by the vehicle speed sensor 44, the greater the rate of reduction of the driving force in response to the acceleration command by the controller 40. Figure 6 , Figure 7 Therefore, there is no need to excessively suppress the acceleration of the vehicle 100, which can prevent the vehicle's posture from becoming unstable.

[0061] It should be noted that in the above embodiment, the controller 40, as the control unit, calculates the correction coefficient γ of the throttle command value Th based on the steering angle θs, the yaw angle θr, and the vehicle speed v. However, it is also possible to calculate the correction coefficient γ based on the steering angle θs and the yaw angle θr instead of considering the vehicle speed v. When calculating the correction coefficient γ based on the steering angle θs, the yaw angle θr, and the vehicle speed v, or based on the steering angle θs and the yaw angle θr, the yaw angle (denoted by θrg) that takes into account the direction of gravity can also be used. This point will be explained below.

[0062] Figure 8 This is a front view of a vehicle 100 situated on sloping ground at an angle (inclination angle) θg formed by the road surface and the horizontal line. Figure 8 In this configuration, the left-right direction of the vehicle 100 aligns with the inclination direction of the road surface (inclined surface). In this state, the angle of the longitudinal frame 20 from the reference line L3 extending along the direction of gravity is defined as the sway angle θrg. This sway angle θrg can be calculated using the value of an inclination sensor (not shown) that detects the inclination angle θg of the road surface. That is, the sway angle θrg of the longitudinal frame 20 relative to the direction of gravity can be calculated using the detected value (θg) of the inclination sensor and the detected value (θr) of the sway angle sensor 43. It should be noted that the inclination sensor can also be, for example, a sway-type or buoy-type sensor installed on the rear frame 12. A gyroscope sensor or a gravity-type inclination sensor can also be used to calculate the sway angle θrg. In other words, the configuration of the sway angle detection unit that detects the sway angle θrg from the reference line L3 can be of any form.

[0063] This configuration allows for the detection (calculation) of the sway angle θrg from the baseline L3 extending in the direction of gravity. Consequently, when the vehicle 100 is traveling on a road surface that is tilted in the left-right direction, the motor output can be effectively suppressed based on the sway angle θg. For example, the sway angle θrg when the longitudinal frame 20 is swaying on the upward tilting side is smaller than the sway angle θr when traveling on a non-tilted surface, thus preventing excessive suppression of the output of the travel motor 4.

[0064] The above embodiments can be modified in various ways. Several modifications will be described below. In the above embodiments, the handlebar 22, which serves as the steering part, is configured as a crossbar, but the configuration of the steering part is not limited to this. In the above embodiments, the pedal 25 (mounting part) is constructed from a single sheet of material, but the mounting part can also be divided into left and right sections. In the above embodiments, the front wheel 1 is supported by the front frame 11 and the longitudinal frame 20 so that it can rotate and be operated by the handlebar 22, but the configuration of the first component is not limited to the above. In the above embodiments, the rear wheel 2 is supported by the rear frame 12 so that it can rotate, but the configuration of the second component is not limited to this.

[0065] In the above embodiment, the first component (front frame 11) is connected by a connecting part 30 equipped with a Nederhardt rubber spring 31, allowing the first component (front frame 11) to swing relative to the second component (rear frame 12) around the centerline CL1 (axis). However, force-applying components other than the Nederhardt rubber spring can also be used, and the configuration of the connecting part is not limited to the above description. In the above embodiment, a travel motor 4 is provided at the front wheel 1 as a travel actuator. However, as long as it is configured to drive at least one of the front wheel 1 and the rear wheel 2, the configuration of the travel actuator is not limited to the above description. The brake (brake unit 5) also contributes to the vehicle's travel action and is included in the travel actuator. Therefore, the controller 40 can control the brake in addition to or in place of the travel motor 4. A prime mover can also be used instead of the travel motor 4 as a travel actuator.

[0066] In the above embodiments, a driving command including an acceleration command is input by operating the throttle lever 24 provided on the handlebar 22. However, a driving command can also be input by pressing the pedal. The configuration of the input unit is not limited to those described above. The driving command includes not only acceleration commands but also deceleration commands. In the above embodiments, the steering angle θs is detected by the steering angle sensor 42, but the configuration of the steering angle detection unit is not limited to those described above. In the above embodiments, the yaw angle θr is detected by the yaw angle sensor 43, but the configuration of the yaw angle detection unit is not limited to those described above. In the above embodiments, the vehicle speed v is detected by the vehicle speed sensor 44, but the configuration of the vehicle speed detection unit is not limited to those described above.

[0067] In the above embodiment, the steering angle θs and the yaw angle θr are used as parameters, according to Figure 5A , Figure 5B The first correction coefficient α was calculated based on the characteristics, but α can also be calculated based on other characteristics. In the above embodiment, the vehicle speed v is used as a parameter, according to... Figure 6 The second correction coefficient β is calculated based on the characteristics, but β can also be calculated based on other characteristics. In the above embodiment, the correction coefficient γ of the throttle command value Th is calculated using the first correction coefficient α and the second correction coefficient β, but the formula for calculating the correction coefficient of the motor command value Th' is not limited to the above. The correction coefficient γ can also be calculated without distinguishing between the first correction coefficient α and the second correction coefficient β. The correction coefficient γ can also be calculated using a map or the like without using a formula. Therefore, the configuration of the control unit is not limited to the above.

[0068] In this embodiment, the vehicle's posture becomes unstable because the steering angle and yaw angle become inappropriate with changes in vehicle speed. Therefore, to improve vehicle posture stability, an actuator (not shown) can apply torque to either the shaft serving as the rotation center of the steering angle or the shaft serving as the rotation center of the yaw angle, or both, to assist in preventing the steering angle and yaw angle from becoming inappropriate. That is, for example, if the yaw angle is insufficient, torque can be applied in the direction that increases the yaw angle; conversely, if the steering angle is too large, torque can be applied in the direction that decreases the steering angle, thus assisting in operation. Consequently, if the steering angle and yaw angle are close to an appropriate state, the output suppression amount for throttle operation controlled as described above decreases.

[0069] In the above embodiment, the vehicle 100 is configured with a single front wheel 1 and a pair of left and right rear wheels 2, but it can also be configured with a single front wheel and a single rear wheel or a pair of front wheels and a single rear wheel. It should be noted that a single wheel also includes, for example, a pair of front wheels located in one place, i.e., a double front wheel.

[0070] The above description is merely an example, and the above embodiments and modifications do not limit the invention as long as they do not destroy its features. One or more of the above embodiments and modifications can be combined in any way, and modifications can also be combined with each other.

[0071] Explanation of reference numerals in the attached figures

[0072] 1: Front wheel;

[0073] 2: Rear wheel;

[0074] 11: Front frame;

[0075] 12: Rear frame;

[0076] 20: Longitudinal frame;

[0077] 22: Handlebars;

[0078] 24: Throttle lever;

[0079] 25: Pedal;

[0080] 30: Connecting part;

[0081] 40: Controller;

[0082] 42: Steering angle sensor;

[0083] 43: Swing angle sensor;

[0084] 44: Vehicle speed sensor;

[0085] 100: Vehicles.

Claims

1. A vehicle characterized by comprising: have: Front wheel (1) and rear wheel (2); A steering unit (22) is positioned above the front wheel (1); The footrest (25) is for the occupant's feet; The first component (11, 20) supports the front wheel (1) so that it can rotate and can be steered according to the steering part (22); The second component (12), which is positioned behind the first component (11, 20), supports the rear wheel (2) so that it can rotate; The connecting part (30) is connected to the first member (11, 20) in such a way that the first member (11, 20) can swing in the left-right direction relative to the second member (12) about an axis (CL1) extending in the front-back direction; A driving actuator (4) that drives at least one of the front wheel (1) and the rear wheel (2); The input unit (24) receives driving commands including acceleration commands; The control unit (40) controls the driving actuator (4) to generate a driving force corresponding to the driving command input by the input unit (24); Steering angle detection unit (42) detects the steering angle of the steering unit (22) in the left and right directions; The swing angle detection unit (43) detects the swing angle of the first member (11, 20) relative to the second member (12) in the left-right direction; and The vehicle speed detection unit (44) detects vehicle speed. The control unit (40) controls the driving actuator (4) to generate a driving force lower than the driving force corresponding to the acceleration command input by the input unit (24) based on the steering angle detected by the steering angle detection unit (42), the sway angle detected by the sway angle detection unit (43), and the vehicle speed detected by the vehicle speed detection unit (44). The control unit (40) calculates a first correction coefficient (α) based on the steering angle and the yaw angle being within the range of greater than 0 and less than 1, calculates a second correction coefficient (β) based on the vehicle speed being within the range of greater than 0 and less than 1, uses the β power of the first correction coefficient (α) as the correction coefficient (γ), calculates the corrected acceleration command obtained by multiplying the correction coefficient (γ) by the acceleration command, and controls the driving actuator (4) to output the driving force corresponding to the corrected acceleration command. The correction coefficient (γ) increases as the first correction coefficient (α) increases, and also increases as the vehicle speed increases.

2. The vehicle according to claim 1, characterized in that, When the steering direction of the steering unit (22) obtained from the detection values ​​of the steering angle detection unit (42) and the swing angle detection unit (43) is not in the same direction as the swing direction of the first member (11, 20), the control unit (40) controls the driving actuator (4) so ​​that the driving force for the same acceleration command is reduced compared with when the steering direction and the swing direction are in the same direction.

3. The vehicle according to claim 2, characterized in that, The larger the steering angle detected by the steering angle detection unit (42), the greater the reduction rate of the driving force for the acceleration command by the control unit (40).

4. The vehicle according to claim 3, characterized in that, The slower the vehicle speed detected by the vehicle speed detection unit (44), the greater the reduction rate of the driving force for the acceleration command is made by the control unit (40).

5. The vehicle according to any one of claims 1 to 4, characterized in that, The swing angle detection unit (43) is configured to detect the swing angle from the reference line (L3) extending in the direction of gravity.

6. The vehicle according to any one of claims 1 to 4, characterized in that, It also includes a force-applying part that applies a rotational force centered on the axis (CL1) to the first member (11, 20) to suppress the swaying of the first member (11, 20) in the left-right direction. The force-applying part includes a buffer (31), the buffer (31) having a shaft member (312), a block member (313) coupled to the shaft member (312), a plurality of elastic members (314) arranged facing each other with a plurality of concave surfaces formed on the block member (313), and a housing member (311) arranged around the plurality of elastic members (314) to restrict the movement of the plurality of elastic members (314).

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