JP4947414B2 - vehicle - Google Patents

Description

  The present invention relates to a vehicle, for example, a vehicle using posture control of an inverted pendulum.

Vehicles that use inverted pendulum attitude control (hereinafter simply referred to as inverted pendulum vehicles) are attracting attention. In the inverted pendulum vehicle, the control unit controls the operation of the rotating body and detects the movement state of the casing while the sensor unit detects the operation state of the casing so that the conveying device is stationary or moved.
In such an inverted pendulum vehicle, techniques described in Patent Documents 1 and 2 have been proposed as techniques for arranging auxiliary wheels that can appear and retract.

Patent Document 1 describes that an auxiliary wheel is brought out and grounded when a passenger gets on and gets off, thereby stabilizing the posture of the vehicle and facilitating getting on and off of the passenger. Further, it describes that the posture of the vehicle is maintained by taking out auxiliary wheels even when the posture control is difficult.
On the other hand, Patent Document 2 describes that an auxiliary wheel is protruded at the time of abnormal operation to hold the vehicle body in a stable state.
JP 2004-74814 A JP 2004-217170 A

However, none of the technologies described in the above-mentioned patent documents stop the vehicle stably with the vehicle tilted. That is, the cited document description technique is a technique for grounding the auxiliary wheel in the horizontal state of the vehicle, and since it is already in the horizontal state when getting on and off the vehicle, there is no particular description on the control at the time of getting on and off the vehicle. .
On the other hand, in the case of a vehicle that stably stops the vehicle while the vehicle is tilted, how to stand the vehicle to start after getting on, and when the vehicle gets off, How to incline and stop the vehicle is an element that affects the ride comfort when getting on and off.

In view of this, the present applicant has proposed in Japanese Patent Application No. 2007-22492 the stand-up control for raising the inverted pendulum vehicle that is stopped in the tilted state and the exit control until the inverted pendulum vehicle is stopped in the tilted state.
However, if the vehicle body stopped in the inclined state is raised or inclined to stop the inverted vehicle, the wheels rotate due to the reaction of the drive torque, and the vehicle moves forward or backward.
In other words, it was impossible to control the standing and tilting without the vehicle moving.

Accordingly, the present invention is capable of performing the tilt for raising elevational without moving the vehicle, and to provide an inverted pendulum vehicle.

(1) In order to achieve the above object, according to the first aspect of the present invention, a vehicle including a riding section and a vehicle body is controlled by controlling the torque of the drive wheel according to the inclination state of the vehicle body and the rotation state of the drive wheel. A vehicle that travels with the main body held in an inverted state, wherein a part of the vehicle is grounded at the time of stoppage, and a limiting mechanism that limits an inclination angle of the vehicle main body. The vehicle while moving the riding part forward by the riding part moving mechanism so that the riding part moving mechanism moving in the front-rear direction and the center of gravity of the vehicle main body are located on a vertical line passing through the ground point of the driving wheel There is provided a vehicle characterized by comprising a standing control means for raising a main body.
(2) In the invention according to claim 2, the standing-up control means is configured such that the center of gravity of the vehicle body is positioned on a vertical line passing through the grounding point of the drive wheel in a state where the inclination angle of the vehicle body is restricted by the restriction mechanism. 2. The vehicle according to claim 1, wherein the vehicle main body is started to stand after the riding section is moved until it is.
(3) In the invention according to claim 3, the standing control means determines whether or not the riding section has moved until the center of gravity of the vehicle body is located on a vertical line passing through the ground point of the drive wheel. The vehicle according to claim 2, wherein the determination is made based on a change in the inclination angle of the main body.
(4) In the invention according to claim 4, the standing control means determines a riding section target position of the riding section and a vehicle body inclination angle target value according to an elapsed time from the start of standing, and the riding section 3. The feedback state of the movement state of the riding section according to a target position, and the feedback control of the inclination state of the vehicle body according to the vehicle body inclination angle target value. Item 4. A vehicle according to Item 3.
(5) In the invention according to claim 5, the standing control means is arranged such that the riding section target position and the vehicle body inclination angle are set so that the standing speed at the start of standing and at the completion of standing is smaller than the standing speed during the standing. The target value is determined, and the vehicle according to claim 4 is provided.
( 6 ) The invention according to claim 6 , further comprising load acquisition means for acquiring a load acting on the riding section, and determining the riding section target position in accordance with the acquired load. 4. A vehicle according to 4 .
(7) In the invention of claim 7, wherein the load acquisition means, the measurement value by the load meter for measuring the mounting load of the riding section or the moving state of the riding section, before Symbol vehicle body inclination state, the drive The vehicle according to claim 6 , wherein an estimated value by a state observer using at least one of the rotation states of the wheels is a load acting on the riding section.

In the present invention, as the center of gravity of the vehicle body is positioned on the vertical line that passes through the ground contact point of the drive wheel, since the slope for raising elevation of the vehicle body while moving the riding section before towards the movement of the vehicle it is possible to perform tilt for causing elevation without.

Hereinafter, a preferred embodiment of a vehicle according to the present invention will be described in detail with reference to FIGS. 1 to 18.
(1) Outline of Embodiment In an inverted vehicle, it may be easier to get on and off the vehicle when the vehicle is tilted than when it is upright. For example, in the case of an inverted vehicle having a riding section at a relatively high position from the ground, it is preferable that the vehicle is in an inclined state because it is difficult for the passenger to get on when the vehicle is upright. In addition, by tilting both, the center of gravity is lowered, and the stability of the vehicle when getting on and off is increased.
In the vehicle of this embodiment, in order to further stabilize the tilted state, a stopper (limitation mechanism) is disposed as a structure fixed to the vehicle body, and the vehicle is located at a position equidistant from the ground point of the drive wheel and the ground point of the stopper. By moving the center of gravity of the main body (excluding drive wheels and drive motors, passengers, stoppers, vehicle bodies, etc.), the vehicle in an inclined state is stably stopped.
In this specification, the state where the front end of the stopper is grounded and the vehicle body is tilted and stopped is referred to as boarding / stopping.

In the boarding / alighting stop state, the center of gravity of the vehicle body is present in front of the vertical line of the contact point of the drive wheel. For this reason, when the vehicle is slowly raised or tilted, if the torque for controlling the standing or tilting is applied to the vehicle body, the wheel rotates due to the reaction and the vehicle moves back and forth. End up.
Therefore, in the present embodiment, by moving the riding section back and forth, even when the vehicle body is tilted, the center of gravity is on the vertical line of the driving wheel grounding point so that the center of gravity does not move. By controlling the inclination angle and the riding section position, the vehicle can stand up and tilt without moving the vehicle (without rotating the wheel).

FIG. 1 shows the state of a vehicle in standing control ((a) to (c)) and boarding / stopping control ((d) to (f)) according to the present embodiment.
In the present embodiment, as shown in FIGS. 1A and 1F, the riding section (seat) 13 is moved forward in the boarding / alighting stop state. In this state, the center of gravity P of the vehicle body is located between the ground point S1 of the drive wheel 12 and the ground point S2 of the stopper 17.
In this way, getting on and off is facilitated by moving the height of the riding section 13 forward.
In this state of boarding / exiting, if a standing-up command is issued after the passenger has boarded, boarding is performed until the center of gravity P is positioned on the vertical line V passing through the grounding point S1, as indicated by an arrow A1 in FIG. The part 13 is moved backward.
Between the start of rearward movement of the riding section 13 and the movement of the center of gravity P onto the vertical line V, both the grounding points S1 and S2 are grounded, and the center of gravity P is between the grounding points S1 and S2. Therefore, the inclination angle of the vehicle body does not change.

When the center of gravity P moves on the vertical line V, as shown in FIG. 1B, the riding part 13 is moved forward as indicated by the arrow A2 so that the center of gravity P does not move from the vertical line V. The vehicle body is raised as indicated by the arrow B1. FIG. 1C shows a state in which the standing control is completed.
Here, the movement of the center of gravity P is eliminated by moving the center of gravity 13 due to the forward movement of the riding section 13 and the center of gravity movement due to the standing of the vehicle body so as to cancel each other.

On the other hand, in the case of the getting-on / off stop control, as shown in FIG. 1D, the riding section 13 is moved to an arrow so that the center of gravity P does not move from the vertical line V from the state where the center of gravity P exists on the vertical line V. While moving backward as indicated by A3, the vehicle body is inclined forward as indicated by arrow B2.
And if the front-end | tip part of the stopper 17 earth | grounds at the grounding point 2, a vehicle will escape from an inverted state and will stop stably. Then, in order to make a vehicle into the initial state of a boarding / alighting stop, by moving the boarding part 13 ahead, a seat surface part is lowered | hung and alighting is made easy. FIG. 1 (f) shows a state where the getting-on / off stop control is completed.

According to the present embodiment, the following effects can be obtained.
(A) In the boarding / alighting stop state, the front end of the stopper is grounded and the center of gravity of the vehicle body exists between the driving wheel and the stopper grounding point, so that the vehicle can be stably stopped and And getting off can be made easy.
(B) Since the vehicle can be slowly raised and tilted without moving, it is possible to eliminate discomfort to the passenger until the completion of the raising and the stop of getting on and off.
(C) Since standing, getting on and off can be performed without moving the vehicle, it is not necessary to secure a wide space forward when getting on and off.

(2) Details of Embodiment FIG. 2 illustrates an external configuration of a vehicle in the present embodiment in a state where an occupant is traveling and traveling forward.
As shown in FIG. 2, the vehicle includes two drive wheels 11a and 11b arranged on the same axis.
Both drive wheels 11a and 11b are driven by drive motors 12a and 12b, respectively.

Boarding on which driving loads 11a and 11b (referred to as driving wheels 11 when referring to both driving wheels 11a and 11b. The same applies to other configurations hereinafter) and the driving motor 12 are loaded with heavy loads, passengers, etc. A portion 13 (sheet) is arranged.
The riding section 13 includes a seat surface section 131 on which a driver sits, a backrest section 132, and a headrest 133.

The riding section 13 is supported by the support member 14 via a moving mechanism (not shown) that functions as a riding section moving mechanism. The support member 14 is fixed to a drive motor housing in which the drive motor 12 is accommodated.
As the moving mechanism, for example, a low-resistance linear moving mechanism such as a linear guide device is used, and the relative position between the riding section 13 and the support member 14 is changed by the driving torque of the riding section drive motor. Yes.

The linear guide device includes a guide rail fixed to the support member 14, a slider fixed to the riding section drive motor, and a rolling element.
In the guide rail, two track grooves are formed linearly along the longitudinal direction on the left and right side surfaces thereof.
The cross section along the width direction of the slider is formed in a U-shape, and two track grooves are formed on the inner sides of the two opposing side surfaces so as to face the track grooves of the guide rail. .
The rolling element is incorporated between the raceway grooves described above and rolls in the raceway groove with the relative linear motion of the guide rail and the slider.
The slider has a return passage that connects both ends of the raceway groove, and the rolling elements circulate between the raceway groove and the return passage.
The linear guide device is provided with a brake (clutch) for fastening the movement of the linear guide device. When the operation of the riding section is unnecessary, the slider is fixed to the guide rail by this brake, so that the relative position between the support member 14 to which the guide rail is fixed and the riding section 13 to which the slider is fixed is fixed. Hold. When the operation is necessary, the brake is released and the distance between the reference position on the support member 14 side and the reference position on the riding section 13 side is controlled to be a predetermined value.

  An input device 30 is arranged beside the riding section 13. This input device 30 is used to give instructions for vehicle acceleration, deceleration, turning, in-situ rotation, stop, braking, etc., as well as instructions for standing up and boarding / stopping in this embodiment. is there.

  The input device 30 in the present embodiment is fixed to the seat surface portion 131, but may be configured by a remote controller connected by wire or wirelessly. Moreover, an armrest may be provided and the input device 30 may be arranged on the upper part thereof.

  Further, although the input device 30 is arranged in the vehicle of this embodiment, in the case of a vehicle that automatically travels according to predetermined travel command data, a travel command data acquisition unit is arranged instead of the input device 30. Established. The travel command data acquisition unit may be configured by, for example, a reading unit that acquires travel command data from various storage media such as a semiconductor memory, and / or a communication control unit that acquires travel command data from the outside through wireless communication. .

Although FIG. 1 shows a case where a person is in the boarding section 13, it is not necessarily limited to a vehicle driven by a person. When stopping, when carrying only a load and making it run or stop according to run command data, it may be a case where it runs and stops in the state where nothing is boarded.
In this case, the stand-up instruction and the get-off instruction are performed by a remote control operation or the like, similarly to the travel command data.
In the present embodiment, control such as acceleration / deceleration is performed according to an operation signal input by operating the input device 30.

A control unit 16 is disposed between the riding section 13 and the drive wheel 11.
In the present embodiment, the control unit 16 is attached to the support member 14.
The control unit 16 may be attached to the lower surface of the seat surface portion 131 of the riding section 13. In this case, the control unit moves back and forth together with the riding section 13 by the moving mechanism.

A pair of stoppers 17 are fixed to the support member 14 and function as a limiting mechanism that limits the inclination angle of the vehicle body when a part of the support member 14 is brought into contact with the vehicle when it is stopped.
The pair of stoppers 17 are arranged so as to sandwich the drive wheel 12, but may be arranged between the drive wheels 12a and 12b.

The stopper 17 has a curved shape extending in the front-rear direction of the vehicle from the position of the support member 14 to be fixed, and the front end portion P1 and the rear end portion P2 are grounded to limit the inclination of the vehicle body. It is supposed to be.
The stopper 17 has the same distance from the rotational axis of the drive wheel 11 to the front end P1 and the distance from the rear end P2, and the front end portion from the ground in the upright state of the vehicle body (the vehicle body tilt angle is zero). The height to P1 and the height to the rear end P2 are the same.
In this embodiment, the boarding / alighting stop is performed in a state where the front end portion P1 is grounded, and the vehicle body inclination angle at this time is set to 15 degrees. The inclination angle when stopping and getting on and off can be set to an arbitrary angle as long as it is larger than the inclination angle of the vehicle body at the time of maximum acceleration of the vehicle.

  Further, the inclination angle of the rear end portion P2 at the time of grounding can be set to any angle as long as it is larger than the vehicle body inclination angle at the time of maximum deceleration of the vehicle. In this embodiment, this inclination angle is also set to the same 15 degrees, but both may be set to different values in accordance with the required acceleration and deceleration.

  The distance from the rotation shaft of the drive wheel 11 to the front end P1 of the stopper 17 is the vehicle center of gravity when the occupant is on board, and the occupant's weight and body shape when the occupant is on boarding, Both are designed so that the center of gravity of the vehicle is located in a region from the contact point of the drive wheel 11 to the front end P1 (vertically above the two points).

  In the present embodiment, a portion excluding the drive wheels 11 and the drive motor 12 among the respective parts constituting the vehicle is referred to as a vehicle main body. The vehicle body includes a riding section 13, a stopper 17, a control device 30, a control unit 16, a moving mechanism, and the like. The vehicle body includes a riding part 13 that moves in the vehicle longitudinal direction by a moving mechanism, and a vehicle body that includes parts other than the riding part 13.

  The vehicle according to the present embodiment includes a battery as another device. The battery supplies drive and calculation power to the drive motor 12, the riding section drive motor, the control ECU 20, and the like.

FIG. 3 shows the configuration of the control system in the first embodiment.
The control system includes a control ECU (electronic control unit) 20 that functions as a standing control unit and a boarding / alighting stop control unit, a control unit 31, a start / alight switch 32, an angle meter (angular velocity meter) 41, a driving wheel rotation angle meter 51, a drive A wheel actuator 52 (drive motor 12), a seat drive motor rotation angle meter (position sensor) 71, a seat drive actuator 72 (ride portion drive motor), and other devices are provided.

The control ECU 20 includes a main control ECU 21 and a drive wheel control ECU 22, and performs various controls such as vehicle travel and attitude control by drive wheel control, vehicle body control (inverted control), and the like. In addition, the control ECU 20 includes a seat control ECU 23, and performs standing-up / alighting stop control by movement of the riding section 13 in the present embodiment.
The control ECU 20 is configured by a computer system including a ROM storing various programs such as a stand-up / alighting stop control program and data in this embodiment, a RAM used as a work area, an external storage device, an interface unit, and the like. Yes.

Connected to the main control ECU 21 are a drive wheel rotation angle meter 51, an angle meter (angular velocity meter) 41, a seat drive motor rotation angle meter (position sensor) 71, and a control device 31 as an input device 30 and an activation / alighting switch 32. Has been.
The control device 31 supplies a travel command based on the operation of the passenger to the main control ECU 21. The control device 31 includes a joystick. The joystick is set to the neutral position in an upright state, instructing acceleration / deceleration by inclining in the front-rear direction, and instructing the turning curvature in the left-right direction by inclining in the left-right direction. The required acceleration / deceleration and the turning curvature increase according to the inclination angle.

The start / drop-off switch 32 is a switch for the passenger to give a start instruction after boarding and a get-off instruction (instruction for shifting to the boarding / stopping state) to the vehicle.
The start / get off switch 32 includes a start instruction switch and a get off instruction switch.

  The main control ECU 21 functions as the vehicle body control system 40 together with the goniometer 41, and performs vehicle body posture control with the counter torque of the drive wheels 12 based on the vehicle body tilt state as posture control of the inverted vehicle.

The main control ECU 21 functions as the drive wheel control system 50 together with the drive wheel control ECU 22, the drive wheel rotation angle meter 50, and the drive wheel actuator 52.
The driving wheel rotation angle meter 51 supplies the rotation angle of the driving wheel 11 to the main control ECU 21, the main control ECU 21 supplies a driving torque command value to the driving wheel control ECU 22, and the driving wheel control ECU 22 drives the driving torque to the driving wheel actuator 52. A drive voltage corresponding to the command value is supplied.
The drive wheel actuator 52 controls both the drive wheels 11a and 11b independently according to the command value.

The main control ECU 21 functions as a seat control system 70 together with the seat control ECU 24, the seat drive motor rotation angle meter (position sensor) 71, and the seat drive actuator 72.
The seat drive motor rotation angle meter 71 supplies the main control ECU 21 with the rotation angle or seat position of the seat drive motor, the main control ECU 21 supplies the drive thrust command value to the seat control ECU 24, and the seat control ECU 24 includes the seat drive actuator. A drive voltage corresponding to the drive thrust command value is supplied to 72.
The seat drive actuator 72 controls the position of the riding section 13 in the direction along the moving mechanism (linear guide device) according to the command value.

The main control ECU 21 functions as drive wheel torque determination means.
The main control ECU 21 functions as an upright control unit and a boarding / alighting stop control unit.

Next, the stand-up / alighting / stopping control in the vehicle configured as described above will be described.
FIG. 4 is a flowchart showing the main flow of the stand-up / alighting stop control.
The main flow of the stand-up / alighting / stopping control shown in FIG. 4 is common to the first to fourth embodiments for the standing-up control and the boarding / alighting stop control described later.

First, the main control ECU 21 obtains a start / get-off instruction switch signal (step 1).
Next, the main control ECU 21 determines whether or not the vehicle body is in an inverted state (step 2). This determination is performed using, for example, a measured value of the vehicle body inclination angle.
When the vehicle body is not in an inverted state (step 2; N) and the start instruction switch is ON (step 3; Y), the main control ECU 21 executes an upright control process described later (step 4), and then the main routine. Return to
In the main routine after the standing control process, normal posture (inverted) control and traveling control are executed.

On the other hand, when the vehicle body is in an inverted state (step 2; Y) and the getting-off instruction switch is ON (step 5; Y), the main control ECU 21 determines whether or not the vehicle is stopped in an inverted state. (Step 6).
Here, the main control ECU 21 considers “stop” when the rotational speeds (absolute values) of the left and right drive wheels 11 are both equal to or less than a predetermined threshold as a determination condition as to whether or not the vehicle is stopped in an inverted state.
For example, when the vehicle is not yet stopped in an inverted state (step 6; N), such as when the vehicle is decelerating to stop, the main control ECU 21 returns to the main routine and determines that the vehicle is stopped (step 6; Y). ) Continue the inverted posture control until

When the main control ECU 21 determines that the vehicle is stopped in an inverted state (step 6; Y), it executes a boarding / stopping control described later (step 7), and then returns to the main routine.
In the main routine after the boarding / stopping control, since the vehicle is in a stopped state, a transition is made to the corresponding processing such as the subsequent stand-up control command and the monitoring of the ignition key off (power-off command).

  In this embodiment, the standing control is performed when the vehicle body is not in an inverted state and the start instruction switch is ON. However, a load sensor or the like is provided on the seat surface portion 131 of the riding section 13 to supply the command for the standing control. You may make it start standing control on the condition of a passenger's seating detection. For example, when seating cannot be detected even when a standing command is given, the standing control is not started. Further, the standing control may be started on the condition that only the seating is detected, even if the activation instruction switch is not operated by the passenger.

  Further, when the vehicle body is in an inverted stop state and the getting-off instruction switch is ON, the getting-on / off stop control is performed, but the main control ECU 21 detects some abnormality and determines that it is difficult to continue the vehicle attitude control. Moreover, you may make it make it transfer to boarding / alighting stop control forcibly.

Next, the contents of the stand-up control (step 4; FIG. 4) in the first embodiment will be described.
FIG. 5 is a flowchart showing the processing content of the standing control in the first embodiment.
In the following description, the riding section 13 is expressed as a seat.
The main control ECU 21 acquires state quantities of vehicle body tilt and wheel rotation from the sensor (step 11). That is, the main control ECU 21 acquires the rotation angle (seat position λ _S ) from the seat drive motor rotation angle meter (position sensor) 71 and acquires the vehicle body inclination angle θ ₁ (angular velocity) from the angle meter (angular velocity meter) 41.

Next, the main control ECU 21 determines the seat position target value λ _S ^* based on each state quantity acquired in step 11 (step 12).
That is, the main control ECU 21 determines the target value λ _S ^* of the seat position by the following formulas 1 and 2.

(Formula 1)
When r <1, λ _S ^* = λ _{S, init} (1−r) + λ _{S, n} r,
When r ≧ 1, λ _S ^* = λ _{S, n}

In Equation 1, a value (r = t / T ₁ ) obtained by making the time t from the start of control dimensionless at a predetermined time T ₁ is represented.
Also, λ _{S, init} represents the sheet position (initial position of the sheet) at the start of this control.
λ _{S, n} is a center-of-gravity correction position of the sheet expressed by Equation 2 described later. The center-of-gravity correction position is a seat (boarding portion) in a state where the center of gravity P of the vehicle main body including the occupant and the seat is located on the vertical line V passing through the contact point S1 of the drive wheel 11 (see FIG. 1B). 13).

T ₁ represents the seat backward movement time, and a preset value is used.
In the present embodiment, as shown in FIG. 6 (a), between the seat backward movement time T _1, from the initial position lambda _{S, init} sheet, so as to vary linearly to the center of gravity correction position lambda _{S, n} Then, the seat target position λ _S ^* is determined.
However, as indicated by the dotted line in FIG. 6A, the amount of change before the movement from the initial position λ _{S, init} to the center of gravity correction position λ _{S, n} before the completion of movement is greater than the amount of change between the two. Alternatively, the sheet target position λ _S ^* may be set so as to be smaller. Thereby, the shock to the passenger accompanying the acceleration / deceleration of the seat movement can be reduced.

The center-of-gravity correction position λ _{S, n} of the sheet is set by the following formula 2. In Equation 2, θ _{1, init} is the initial inclination angle of the vehicle body (value at the start of this control).
Further, l ₁ is the center-of-gravity distance from the axle of the vehicle main body, m _s is the riding section mass, and m ₁ is the mass of the vehicle main body (including the riding section).

(Formula 2)
λ _{S, n} = −l ₁ (m ₁ / m _s ) tan θ _{1, init}

Next, the main control ECU 21 determines a seat drive thrust command value S _S by the seat drive actuator 72 (step 13). That is, the main control ECU 21 uses the determined seat target position λ _S ^* to determine the seat drive thrust command value S _S according to the following Equation 3.
Here, {x} represents a time derivative of x, for example, {λ _S } represents a time derivative of λ _S. The same notation is used in the following description.

(Formula 3)
S _S = S _{S, f} −K _S7 (λ _S −λ _S ^* ) − K _S8 ({λ _S } − {λ _S ^* })

In Equation 3, λ _S is the current sheet position detected by the sheet drive motor rotation angle meter 71. This value lambda _S is to coincide with the seat position target value lambda _S ^* determined in step 11 is feedback-controlled.
K _S7 and K _S8 are feedback gains, and for example, values set in advance by the pole placement method are used.
S _{S, f} represents a feed forward torque for dry friction and gives a set value, and its positive / negative is changed in accordance with the moving direction (a negative value in the case of backward movement). Instead of S _{S, f} , an integral gain of the seat position deviation (λ _S −λ _S ^* ) may be given.
In the present embodiment, Equation 3 is used, but the first and third terms are terms for improving accuracy and may be omitted. For example, S _S = −K _S7 (λ _S −λ _S ^* ) may be given.

Next, the main control ECU 21 gives the determined drive thrust command value S _S to the seat control system 70 (step 14). That is, the main control ECU 21 supplies the determined seat drive thrust command value S _S to the seat control ECU 24, and the seat control ECU 24 supplies a drive voltage corresponding to the drive thrust command value S _S to the seat drive actuator 72.
As a result, the seat (the riding section 13) moves rearward toward the seat target position λ _S ^* .

Next, the main control ECU 21 determines whether or not the moved sheet has reached the center of gravity correction position (step 15). Here, the center-of-gravity correction position refers to a seat position when the center of gravity P of the vehicle main body is on a vertical line passing through the ground point S1 of the drive wheel 11, as shown in FIG.
When it is determined that the seat has reached the center of gravity correction position (step 15; Y), the main control ECU 21 proceeds to the processing after step 21 and starts to stand the vehicle body.

On the other hand, if the seat has not reached the center of gravity correction position (step 15; N), the main control ECU 21 determines whether or not the vehicle body has started to rise (step 16). The determination as to whether or not the vehicle body has started to rise is, for example, determined as “rise” when the amount of change from the initial value of the vehicle body inclination angle is equal to or greater than a predetermined threshold.
In this way, whether or not the vehicle body has started to rise before the seat reaches the center-of-gravity correction position λ _{S, n} of the seat set according to Equation 2 is determined from Equation 2. This is because the vehicle body may start to rise due to a parameter error or disturbance with respect to the center-of-gravity correction position λ _{S, n} as a calculated value. For example, the case where the actual occupant weight is significantly different from the assumed value and the center of gravity of the vehicle main body is deviated from the assumed position, or the case where the vehicle wakes up due to a disturbance such as wind power is applicable.
Thus, when the rising of the vehicle main body is detected (step 16; Y), the main control ECU 21 has reached the vertical line V passing through the ground point S1 of the drive wheel 11 with the actual center of gravity P of the vehicle main body. (Refer to FIG. 1 (b)), the rearward movement of the seat is immediately stopped, and the vehicle shifts to step 21.

When the seat has not reached the center-of-gravity correction position λ _{S, n} (step 15; N) and the vehicle body has not started to rise (step 16; N), the main control ECU 21 returns to step 11 to place the seat at the center-of-gravity correction position. Repeat the movement.
In the processing from step 11 to step 16 described above, after the standing control command is issued in the boarding / alighting stop state (FIG. 1A), the seat (boarding portion 13) is moved rearward, and the center of gravity P of the vehicle main body P Is a process until it reaches the vertical line V passing through the ground contact point S1 of the drive wheel 11 (FIG. 1B).

  After the center of gravity P of the vehicle main body reaches the vertical line V passing through the contact point S1 of the drive wheel 11 (steps 15; Y, 16; Y), the main control ECU 21 raises the vehicle main body through steps 21 to 25. Let The processing from Step 21 to Step 25 is performed after the center of gravity P of the vehicle body moves to the center of gravity correction position (position on the vertical line V) (FIG. 1B) until the vehicle body is completely raised (FIG. 1). (C)). In the process during this time, the center of gravity position P of the vehicle body and the position of the vehicle are controlled so as not to move.

First, the main control ECU 21 acquires each state quantity from the sensor (step 21). That is, the main control ECU 21 determines the rotation angle (seat position λ _S ) from the seat drive motor rotation angle meter (position sensor) 71, the vehicle body inclination angle θ ₁ (angular velocity) from the angle meter (angular velocity meter) 41, and the drive wheel rotation angle. The driving wheel rotation angle θ _W is acquired from the total 51.

Next, the main control ECU 21 determines target values λ _S ^* and θ ₁ ^* of the seat position and the vehicle body inclination angle (step 22). That is, the main control ECU 21 determines the target value λ _S ^* of the seat position according to Formula 4, and determines the target value θ ₁ ^* of the vehicle body tilt angle according to Formula 5 using the target value λ _S ^* .

(Formula 4)
When r <1, λ _S ^* = λ _{S, init2} (1-r),
When r ≧ 1, λ _S ^* = 0 (r ≧ 1)

(Formula 5)
θ ₁ ^* = − tan ⁻¹ (m _S λ _S ^* / m ₁ l ₁ )

In Equation 4, r represents a value (r = t / T ₂ ) obtained by making the time t from the start of this control loop (step 21 to step 25) dimensionless at a predetermined time T ₂ . In addition, λ _{S, init2} represents the sheet position (initial position of the sheet) at the same time.
λ _{S, n} represents the center of gravity correction position of the sheet described above.
T ₂ represents the seat forward movement time, and a preset value is used. In this embodiment, as shown in FIG. 6B, during the seat forward movement time T ₂ , the seat reference position of λ _S ^* = 0 from the initial seat position λ _{S, init2} The seat target position λ _S ^* is determined such that the center of gravity P of the main body linearly changes to the seat position on the vertical line passing through the ground point S1 of the drive wheel 11. Further, as shown in FIG. 6C, during the seat forward movement time T ₂ , the curve expressed by Equation 5 from the target value θ ₁ ^* of the vehicle body inclination angle to the upright posture of θ ₁ ^* = 0. The vehicle body tilt target value θ ₁ ^* is determined so as to change along
However, as indicated by the dotted lines in FIGS. 6B and 6C, when the movement starts from the initial position, the sheet target position is set so that the amount of change before completion of movement is smaller than the amount of change between the two. λ _S ^* and the vehicle body tilt target position θ ₁ ^* may be set. Thereby, the shock to the passenger accompanying the acceleration and deceleration of the seat movement and the vehicle body standing can be reduced.

Next, the main control ECU 21 determines command values S _S and τ _W for each actuator (step 23). That is, the main control ECU 21 uses the determined seat position and the target values λ _S ^* and θ ₁ ^{* of the} vehicle body inclination angle to calculate the seat drive thrust command value S _{S according} to Equation 6 and the drive wheel torque command value τ _W according to Equation 7. Respectively.

(Formula 6)
S _S = S _{S, f} −K _S7 (λ _S −λ _S ^* ) − K _S8 ({λ _S } − {λ _S ^* })

(Formula 7)
τ _W = −K _W2 {θ _W } + K _W3 (θ ₁ −θ ₁ ^* ) + K _W4 ({θ ₁ } − {θ ₁ ^* })

In Equation 7, K _W2 , K _W3 , K _W4 , K _S7 , and K _S8 are feedback gains, and for example, values set in advance by the pole placement method are used.
In the feedback control according to Equation 7, the seat position and speed may be taken into consideration.
In Equation 6, an integral gain may be given instead of the feedforward torque S _{S, f} for dry friction.

Next, the main control ECU 21 gives command values S _S and τ _W to each control system (step 24). That is, the main control ECU 21 supplies the determined command values S _S and τ _W to the seat control ECU 24 and the drive wheel control ECU 22, respectively.
Thus, the drive wheel control ECU22, by supplying a driving voltage corresponding to the command value tau _W to the driving wheels actuator 52, gives a drive torque tau _W to the driving wheels 11. The sheet control ECU24 is a drive voltage corresponding to the command value S _S to supply the sheet drive actuator 72 to move the seat (riding section 13) forward.
Then, the vehicle body stands up while gradually reducing the inclination angle θ by the drive torque τ _W from the drive wheels 11, and the amount of center of gravity movement due to the standing up is canceled out by the forward movement of the seat. For this reason, the standing operation is performed without the vehicle moving back and forth.

Next, the main control ECU 21 determines whether or not the standing is completed and the head is in an inverted state (step 25). For example, when the vehicle body inclination angle (absolute value) is equal to or less than a predetermined threshold, the main control ECU 21 determines “inverted (= standup completion)”.
When the vehicle body has not reached the inverted state (step 25; N), the main control ECU 21 returns to step 21 and continues the standing control.
On the other hand, when the standing state has been reached (step 25; Y), the main control ECU 21 ends the standing control process according to the present embodiment. Thereafter, the main control ECU 21 performs vehicle attitude (inversion) control and travel control in the inverted state.

Next, the contents of the boarding / alighting stop control (step 7; FIG. 4) in the first embodiment will be described.
FIG. 7 is a flowchart showing the processing contents of the boarding / alighting stop control in the first embodiment.
In the boarding / alighting stop control shown in FIG. 7, the processing from step 31 to step 36 moves the vehicle back and forth without moving the center of gravity P of the vehicle body from the inverted state (FIG. 1 (d)). Rather, the process is to ground the stopper front end S2, that is, the process up to the boarding / stopping state (FIG. 1 (f)).
Further, the processing from step 41 to step 45 is processing for moving the seat to the foremost position (boarding / alighting assistance position) in order to assist the passenger to get off in the boarding / stopping state.

The main control ECU 21 acquires each state quantity from the sensor (step 31). That is, the main control ECU 21 determines the rotation angle (seat position λ _S ) from the seat drive motor rotation angle meter (position sensor) 71, the vehicle body inclination angle θ ₁ (angular velocity) from the angle meter (angular velocity meter) 41, and the drive wheel rotation angle. The driving wheel rotation angle θ _W is acquired from the total 51.

Next, the main control ECU 21 determines the target value λ _S ^* of the seat position and the target value θ ₁ ^* of the vehicle body inclination angle (step 32). That is, the main control ECU 21 determines the target value λ _S ^* of the seat position by the following formulas 8 and 9. Further, the target value θ ₁ ^* of the vehicle body inclination angle is determined by Expression 10 using the determined target value λ _S ^* of the seat position.

(Formula 8)
λ _S ^* = λ _{S, n} r

(Formula 9)
λ _{S, n} = −l ₁ (m ₁ / m _s ) tan θ _{1, F}

(Formula 10)
θ ₁ ^* = − tan ⁻¹ (m _S {λ _S ^* } / m ₁ l ₁ )

In Equation 8, r represents a value (r = t / T ₂ ) obtained by making the time t from the start of this control loop (step 31 to step 36) dimensionless at a predetermined time T ₂ . T ₂ represents the seat rearward movement time, and a preset value is used.
λ _{S, n} is the center-of-gravity correction position of the sheet, and is calculated by Equation 9. The center-of-gravity correction position is the position of the seat (the riding section 13) when the center of gravity P of the vehicle body is on the vertical line V passing through the contact point S1 of the driving wheel when the vehicle body is in contact with the ground (when the boarding / alighting stop state).
In Equation 9, θ _{1 and F} are values set in advance in the state in which the stopper front end S2 is in contact with the ground, that is, the inclination angle of the vehicle body (vehicle body contact inclination angle) in the stoppage state. However, at the time of standing control shown in FIG. 5, the value immediately before the vehicle body stands (value in the boarding / stopping state) may be stored and used.

According to Expressions 8 and 9, the target value λ _S ^{* of the} seat position and the target value θ of the vehicle body inclination angle as represented by the solid lines in FIGS. 8A and 8B with respect to the seat rearward movement time T ₂ . ₁ ^* is set, but by setting an operation as shown by a dotted line, a shock to the passenger accompanying the acceleration / deceleration of the seat movement and the vehicle body inclination may be reduced.

Next, the main control ECU 21 determines command values S _S and τ _W for each actuator (step 33). That is, the main control ECU 21 calculates the seat drive thrust command value S _{S according} to Formula 11 from the seat position and the target values λ _S ^* and θ ₁ ^{* of the} vehicle body tilt angle determined by Formula 8 to Formula 10, and the drive wheel according to Formula 12. The torque command value τ _W is determined respectively.

(Formula 11)
S _S = S _{S, f} −K _S7 (λ _S −λ _S ^* ) − K _S8 ({λ _S } − {λ _S ^* })

(Formula 12)
τ _W = −K _W2 {θ _W } + K _W3 (θ ₁ −θ ₁ ^* ) + K _W4 ({θ ₁ } − {θ ₁ ^* })

In Equation 12, K _W2 , K _W3 , K _W4 , K _S7 , and K _S8 are feedback gains, and for example, values set in advance by the pole placement method are used.
Note that in the feedback control of Formula 12, the position and speed of the seat may be taken into consideration.
Further, in Formula 11, an integral gain may be given instead of the feedforward torque S _{S, f} for dry friction.

Next, the main control ECU 21 gives command values S _S and τ _W to each control system (step 34). That is, the main control ECU 21 supplies the determined command values S _S and τ _W to the seat control ECU 24 and the drive wheel control ECU 22, respectively.
Thus, the drive wheel control ECU22, by supplying a driving voltage corresponding to the command value tau _W to the driving wheels actuator 52, gives a drive torque tau _W to the driving wheels 11. The sheet control ECU24 is a drive voltage corresponding to the command value S _S to supply the sheet drive actuator 72 to move the seat (riding section 13) backward.
Then, the vehicle body is inclined while gradually increasing the inclination angle θ by the drive torque τ _W from the drive wheel 11, and the center of gravity movement amount due to the vehicle body inclination is canceled by the rearward movement of the seat. For this reason, the forward tilting operation is performed without the vehicle moving back and forth.

Next, the main control ECU 21 arrives at the center of gravity correction position, that is, the seat position when the center of gravity P of the vehicle body in the vehicle ground contact state (boarding / stopping state) is on the vertical line V passing through the ground point S1 of the drive wheel. It is determined whether or not (step 35).
If the seat has not reached the center of gravity correction position (step 15; N), the main control ECU 21 returns to step 31 and continues the rearward movement of the seat and the forward tilt of the vehicle body.
When the seat reaches the center-of-gravity correction position (step 35; Y), the main control ECU 21 further determines whether or not the vehicle main body is actually grounded, that is, whether or not the front end S2 of the stopper 17 is grounded. Judgment is made (step 36). For example, when the vehicle body inclination angle is equal to or greater than a predetermined threshold, the main control ECU 21 determines that “grounding (= tilt completion)”.
When the vehicle body is not grounded (step 36; N), the seat has moved to the calculated center of gravity correction position. However, as in the case of standing control, the seat of the vehicle body is caused by parameter error or disturbance. Since it is assumed that the center of gravity P has not actually reached the center of gravity correction position, the main control ECU 21 returns to step 31 and continues to move the seat backward and tilt the vehicle body forward.

When the processing from the inverted state by the loop of step 31 to step 36 to the boarding / alighting stop state is completed, the main control ECU 21 performs the getting-off assistance processing by the loop of step 41 to step 45.
First, the main control ECU 21 acquires the current seat position (rotation angle) λ _S from the seat drive motor rotation angle meter (position sensor) 71 (step 41).
Next, the main control ECU 21 determines the target value λ _S ^* of the seat position from the following equation 13 (step 42).

(Formula 13)
When r <1, λ _S ^* = λ _{S, init1} (1−r) + λ _{S, end} r,
When r ≧ 1, λ _S ^* = λ _{S, end}

In Equation 13, r represents a value (r = t / T ₁ ) obtained by making the time t from the start of sheet movement dimensionless at a predetermined time T ₁ .
In addition, λ _{S, init1} represents the sheet position (initial position of the sheet) at the same time.
λ _{S, end} is a boarding / alighting assist position calculated by Equation 14 to be described later. The boarding / alighting assist position is a seat setting position when the passenger gets on and off, and in this embodiment, the center of gravity of the vehicle body is located at a point equidistant from the driving wheel grounding point S1 and the stopper grounding point S2 (see FIG. 1). The sheet position is set such that P is located.
In addition, although the above-mentioned position is set as the seat position where the vehicle body stability at the time of passenger getting on and off is set as the top priority, the boarding assistance position of this embodiment places importance on the ease of getting on and off of the passenger, You may make it move a boarding / alighting assistance position (seat position) further forward (stopper contact point S2 side). Further, in order to shorten the time from boarding to standing or from the inclination to getting off the vehicle, the amount of movement of the seat may be reduced by setting the boarding / alighting assistance position further rearward (drive wheel grounding point S1 side).

T ₁ represents the seat forward movement time, and a preset value is used.
In the present embodiment, as shown in FIG. 8C, during the seat forward movement time T ₁ , it changes linearly from the initial position λ _{S, init1} of the seat to the assisting position λ _{S, end.} Then, the seat target position λ _S ^* is determined.
However, as indicated by the dotted line in FIG. _8C , the amount of change immediately after the start of movement from the initial position λ _{S, init1} and immediately before completion of movement from the boarding / _alighting assist position λ _{S, end} is the amount of change between the two. Alternatively, the sheet target position λ _S ^* may be set to be smaller. Thereby, the shock to the passenger accompanying the acceleration / deceleration of the seat movement can be reduced.

The boarding / alighting assistance position λ _{S, end} is calculated from the following Expression 14.
In Equation 14, d is the distance from the center plane of the vehicle body (a plane passing through the center of gravity of the vehicle body and the axle of the drive wheel) to the front end S2 of the stopper 17, M is the total vehicle weight, θ _{1, init1} Is the vehicle body inclination angle.
Further, l ₁ is the center-of-gravity distance from the axle of the vehicle main body, m _s is the riding section mass, and m ₁ is the mass of the vehicle main body (including the riding section).

(Formula 14)
λ _{S, end} = (d / 2) (M / m _S ) −l ₁ (m ₁ / m _S ) tan θ _{1, init1}

Next, the main control ECU 21 determines a seat drive thrust command value S _S by the seat drive actuator 72 (step 43). That is, the main control ECU 21 uses the determined seat target position λ _S ^* to determine the seat drive thrust command value S _S according to the following Expression 15.
In Equation 15, K _S7 and K _S8 are feedback gains, and for example, values set in advance by the pole placement method are used.
S _{S, f} represents a feed forward torque for dry friction and gives a set value, and its positive / negative is changed in accordance with the moving direction (a negative value in the case of backward movement). An integral gain may be given instead of S _{S, f} .

(Formula 15)
S _S = S _{S, f} −K _S7 (λ _S −λ _S ^* ) − K _S8 ({λ _S } − {λ _S ^* })

Next, the main control ECU 21 gives the determined thrust command value S _S to the seat control system 70 (step 44). That is, the main control ECU 21 supplies the determined seat drive thrust command value S _S to the seat control ECU 24, and the seat control ECU 24 supplies a drive voltage corresponding to the drive thrust command value S _S to the seat drive actuator 72.
As a result, the seat (the riding section 13) moves forward toward the seat target position λ _S ^* .

Next, the main control ECU 21 determines whether or not the moved seat has reached the boarding / alighting assist position (step 45), and if not (step 45; N), the main control ECU 21 returns to step 41. Continue to move the seat forward.
On the other hand, if it is determined that the seat has reached the boarding / alighting assist position (step 45; Y), the main control ECU 21 ends the movement of the seat and ends the boarding / alighting stop control.
In the present embodiment, the seat movement is terminated when the seat reaches the boarding / alighting assistance position, but the seat movement may be terminated when the passenger switches the getting-off switch to OFF.

Next, a second embodiment will be described.
In the second embodiment, a balancer (weight body) that can move in the front-rear direction of the vehicle is disposed, and the vehicle body standing in the standing-up control described in the first embodiment (steps 21 to 25), and getting on and off In the process of tilting the vehicle body in the stop control (steps 31 to 36), due to the influence of parameter error, disturbance, etc., the balance of the tilt of the vehicle body and the movement of the seat cannot be maintained well and the vehicle moves. Some of the effects are compensated with a balancer. That is, the balancer is used for delicate balance adjustment of the vehicle body.
In the present embodiment, it is assumed that the balancer has a smaller weight than the total weight of the vehicle body. As the balancer, for example, (a) linear movement type, (b) rotary pendulum type, and (c) rotary inverted pendulum type can be used.
Here, the balancer is a part of the mass of the vehicle body that does not include the riding section. The balancer moves the vehicle body center axis (straight line passing through the center of gravity of the vehicle body and the vehicle body rotation center) and the wheel rotation center axis by an actuator attached to the vehicle body. It is defined as the part that can be moved freely in the vertical direction.

FIG. 9 shows a configuration of a vehicle control unit in the second embodiment. Portions that are the same as those of the control unit in the first embodiment shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted as appropriate.
As shown in FIG. 9, the control system in the second embodiment further includes a balancer control ECU 23, a balancer drive motor rotation angle meter 61, and a balancer drive actuator (motor) 62. It functions as a control system 60.

The balancer drive motor rotation angle meter (position sensor) 61 supplies a motor rotation angle corresponding to the balancer position to the main control ECU 21, the main control ECU 21 supplies a drive thrust command value to the balancer control ECU 23, and the balancer control ECU 23 Then, a drive voltage corresponding to the drive thrust command value is supplied to the balancer drive actuator 62.
Other configurations are the same as those of the first embodiment described in FIG.

FIG. 10 illustrates a configuration example of a balancer moving mechanism that moves the balancer 134 to an arbitrary position.
This balancer moving mechanism functions as a weight body moving means and constitutes a part of the vehicle body. The balancer moving mechanism moves the center of gravity of the vehicle body by moving the balancer 134, which is a heavy body, in the front-rear direction.
The balancer 134 is disposed between the riding section 13 and the drive wheel 11. The balancer 134 is configured to be movable in the front-rear direction (a direction perpendicular to the vehicle body central axis and the wheel rotation central axis) by the balancer drive actuator 62.

  The balancer moving mechanism of FIG. 10A according to the present embodiment moves the balancer 134 linearly on the slider by the slider type actuator 135.

The balancer moving mechanism shown in FIGS. 10B and 10C is a mechanism using a rotationally moving balancer. A balancer 134 is disposed at one end of the support shaft 136, and the rotors of the balancer support shaft rotation motors 137 and 138 are fixed to the other end of the support shaft 136.
Then, the balancer support shaft motors 137 and 138 move the balancer 134 on a circumferential path whose radius is the support shaft 136.
In the balancer moving mechanism shown in FIG. 10B, the balancer support shaft rotating motor 137 is disposed below the seat surface portion 131, and the balancer 134 moves on the lower side of the circumferential track.
In the balancer moving mechanism of FIG. 10C, the balancer support shaft rotating motor 138 is disposed coaxially with the drive wheel 11, and the balancer 134 moves on the upper side of the circumferential track.

As another example of the balancer moving mechanism, the balancer 134 may be moved by a telescopic actuator.
For example, one end of each of the two telescopic actuators is fixed to the front and rear of the vehicle, the other end is fixed to the balancer 134, one of the two telescopic actuators is extended, and the other is contracted, thereby making the balancer 134 straight. It may be moved.

FIG. 11 illustrates a dynamic model of a vehicle attitude control system including the balancer of the present embodiment. Other parts of the dynamic model excluding the balancer can be applied to other embodiments.
The balancer 134 in FIG. 11 illustrates the case of FIG. 10A that moves in a direction perpendicular to the axle and the vehicle central axis.

Each symbol in FIG. 11 is as follows.
(A) State quantity θ _W : Tire rotation angle [rad]
θ ₁ : tilt angle of main body (vertical axis reference) [rad]
λ ₂ : Balancer position (vehicle center axis reference) [m]
λ _S : seat position (vehicle center axis reference) [m]
(B) Input τ _W : Drive motor torque (two wheels total) [Nm]
S _B : Balancer drive thrust [N]
S _S : Seat driving force [N]
(C) Parameter m _W : Tire mass [kg]
R _W : Tire radius [m]
I _W : Tire inertia moment (around axle) [kgm ² ]
m ₁ : Mass of the main body (including passengers) [kg]
l ₁ : Distance from the center of gravity of the main unit (from the axle) [m]
I ₁ : Moment of inertia of body (around center of gravity) [kgm ² ]
m ₂ : Mass of the balancer [kg]
l ₂ : Balancer center of gravity distance (from axle) [m]
I ₂ : Balancer's moment of inertia (around the center of gravity) [kgm ² ]
m _S : Mass of riding section [kg]
The balancer position λ ₂ is positive in front of the vehicle (same as the positive direction of the vehicle body inclination angle θ ₁ ).

Next, the vehicle standing up control and boarding / stopping control in the second embodiment configured as described above will be described.
FIG. 12 is a flowchart showing the processing content of the standing control in the second embodiment.
In the description of the configuration diagrams and flowcharts in each embodiment described below, the same reference numerals and step numbers are assigned to the same parts as those in the first embodiment, and the description of the same parts is appropriately omitted.
In the standing control in the second embodiment, the main control ECU 21 moves the seat (the riding section 13) backward after the standing control command is issued in the boarding / alighting stop state (FIG. 1A), as in the first embodiment. The center of gravity P of the vehicle main body is moved to the vertical line V (FIG. 1B) passing through the ground point S1 of the drive wheel 11 (steps 11 to 16).

When the center of gravity P of the vehicle body moves onto the drive wheel set point S1, the main control ECU 21 acquires the seat position λ _S , the vehicle body inclination angle θ ₁ , and the drive wheel rotation angle θ _W from each sensor (step 21), and further The rotation angle (balancer position λ ₂ ) is acquired from the balancer drive motor rotation angle meter (position sensor) 61 (step 22).
Next, the main control ECU 21 determines the target value λ _S ^* of the seat position according to Formula 4, and uses the determined target value λ _S ^* to determine the target value θ ₁ ^* of the vehicle body tilt angle according to Formula 5 respectively. Determine (step 22). The target value of the balancer is the reference position, that is, λ _B ^* = 0.
Then, the main control ECU 21 uses the determined seat position and the target values λ _S ^* and θ ₁ ^{* of the} vehicle body tilt angle to calculate the seat drive thrust command value S _{S according} to Equation 6 and the drive wheel drive torque command value τ according to Equation 7. Each _W is determined (step 23).

Next, the main control ECU 21 determines a drive thrust command value S _B for the balancer according to the following equation 16 (step 232).

(Formula 16)
S _B = −K _B1 θ _W −K _B2 {θ _W } −K _B5 λ ₂ −K _B6 {λ ₂ }
In Equation 16, K _B1 and K _B2 are feedback gains that suppress movement of the vehicle (rotation of the drive wheels), and K _B5 and K _B6 are feedback gains that control the position of the balancer itself. Each feedback gain is set in advance by, for example, a pole placement method.
In Formula 16, by giving a feedback gain K _B1 to the rotation angle θ _W of the drive wheel 11, the steady deviation of the drive wheel rotation speed (vehicle movement at a constant speed) is reduced, and the movement amount of the vehicle is suppressed. I am doing so.

Next, the main control ECU 21 supplies the command values S _S and τ _W determined to the seat control ECU 24 and the drive wheel control ECU 22 (step 24), and further supplies the command value S _B determined by Expression 16 to the balancer control ECU 23. (Step 242).
Thus, the drive wheel control ECU 22 raises the vehicle body by supplying a drive voltage corresponding to the command value τ _W to the drive wheel actuator 52, and the seat control ECU 24 applies the drive voltage corresponding to the command value S _S to the seat. By supplying the drive actuator 72, the seat (the riding section 13) is moved forward.
The balancer control ECU 23 moves the balancer by driving the balancer drive actuator 62 with a drive voltage corresponding to the command value S _B , thereby canceling the deviation of the center of gravity movement amount associated with the standing of the vehicle body and the forward movement of the seat. Suppresses moving back and forth.

  Next, the main control ECU 21 determines whether or not the standing has been completed (step 25). If it has not been completed (step 25; N), the main control ECU 21 returns to step 21 to continue the standing control and reach the standing state. If this is the case (step 25; Y), the standing-up control process according to the present embodiment is terminated.

Next, the boarding / alighting stop control process in the second embodiment will be described with reference to the flowchart of FIG.
The main control ECU 21 acquires the seat position λ _S , the vehicle body inclination angle θ ₁ , and the drive wheel rotation angle θ _W from each sensor (step 31), and further acquires the balancer position λ ₂ from the balancer drive motor rotation angle meter 61. (Step 312).
Then, the main control ECU 21 determines the target value λ _S ^* of the seat position by Expression 8 and Expression 9, and determines the target value θ ₁ ^* of the vehicle body inclination angle by Expression 10 (Step 32).
The balancer target position is the reference position (λ _B ^* = 0) as in the standing control.

Next, the main control ECU 21 determines the seat drive thrust command value S _{S according} to Formula 11 from the seat position determined by Formula 8 to Formula 10 and the target values λ _S ^* and θ ₁ ^{* of the} vehicle body tilt angle, and Formula 12 Thus, the drive wheel torque command value τ _W is determined (step 33).
Further, the main control ECU 21 determines the balancer drive thrust command value S _B using the equation 16 described in the standing control of the second embodiment (step 332).

Next, the main control ECU 21 supplies the determined command values S _S and τ _W to the seat control ECU 24 and the drive wheel control ECU 22, respectively (step 34), and further, the command value S _B determined by the equation 16 to the balancer control ECU. Is supplied (step 342).
Thus, the drive wheel control ECU 22 tilts the vehicle body by supplying a drive voltage corresponding to the command value τ _W to the drive wheel actuator 52, and the seat control ECU 24 applies the drive voltage corresponding to the command value S _S to the seat. By supplying the drive actuator 72, the seat (the riding section 13) is moved backward.
Then, the balancer control ECU 23 moves the balancer by driving the balancer drive actuator 62 with a drive voltage corresponding to the command value S _B , and the center-of-gravity movement amount associated with the inclination of the vehicle body and the rearward movement of the seat as in the case of standing up. This cancels the deviation and prevents the vehicle from moving back and forth.

Next, the main control ECU 21 determines whether or not the seat has reached the center of gravity correction position and whether or not the vehicle body is grounded (steps 35 and 36). When the seat has reached the center of gravity correction position (step 35; N), or when the vehicle body is not grounded (step 36; N), the main control ECU 21 returns to step 31 and moves the seat backward and the vehicle body. Continue to lean forward.
On the other hand, when the seat has reached the center of gravity correction position (step 35; Y) and the vehicle body is in contact with the ground (step 36; Y), as in the first embodiment, a vehicle exit assistance by a loop from step 41 to step 45 Perform the process.

In the second embodiment, the balancer is used for delicate balance adjustment of the vehicle main body against disturbance or the like, but may be used as assistance for moving the vehicle center of gravity by moving the seat. For example, when the seat is moved backward from the boarding / alighting assist position at the beginning of the standing control (steps 11 to 16), the balancer is also moved backward to reduce the amount of seat movement necessary for moving the center of gravity. Can be shortened.
In addition, when the seat is moved forward from the center of gravity correction position (steps 41 to 45) in the boarding / alighting stop control described later (steps 41 to 45), the center of gravity P of the vehicle body is moved to the driving wheel ground contact point S1 and the stopper by moving the balancer backward. While being held at the intermediate position of the contact point S2, the getting-off assist position can be moved further forward, which makes it easier for the rider to get on and off.

Next, a third embodiment will be described.
In the third embodiment, the mass of the riding section 13 (passenger and seat) is measured, and the control parameter is corrected according to the measured value, so that the standing control and the boarding / stopping control are performed more stably. It is.
FIG. 14 illustrates a configuration of a vehicle control system according to the third embodiment. Portions that are the same as those in the control system in the first embodiment shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted as appropriate.
As shown in FIG. 14, the control system in the third embodiment includes a seat load meter 73 as part of the seat control system 70 detects the riding section load (vertical load) W _S, the main control The ECU 21 is supplied.
In the third embodiment, the riding section mass is evaluated using a load meter. However, the riding section mass may be evaluated using a discrete measurement method in which the mass is evaluated step by step with a simple system. Alternatively, the passenger himself / herself may input mass (weight) and use the input value.

Next, standing control and boarding / stopping control in the third embodiment configured as described above will be described. In addition, the same step number is attached | subjected to the process similar to standing control and boarding / alighting stop control in 1st Embodiment, and the description is abbreviate | omitted suitably.
FIG. 15 is a flowchart showing the processing content of the standing up control in the third embodiment.
The main control ECU 21 acquires the vertical load (carrying part load W _S ) acting on the seat from the seat load meter 73 (step 101), and determines the riding part mass m _S by the following equation 17 (step 102).

(Formula 17)
m _S = m _{S, 0} + W _S / g cos θ ₁

In Equation 17, m _{S, 0} is the non-fluctuating portion of the riding section mass (mass without depending on the presence or absence of the passenger; seat, etc.), W _S is the riding section load (vertical force) acquired in step 101, and g is the gravitational acceleration. , Θ ₁ is the vehicle body inclination angle.
Here, the riding section mass m _S is the mass of a portion that can be moved by the seat control system, and includes the mass of the loaded object when not only the passenger but also a load is loaded.
In this embodiment, a load meter that measures a vertical load (a component perpendicular to the seating surface) is used, but a load meter that can also measure a horizontal component may be used. In this case, the riding section mass m _S can be determined without using the value of the vehicle body inclination angle θ ₁ .

Note that a high-frequency component may be removed by applying a low-pass filter to the riding section mass m _S obtained by Expression 17. Thereby, the vibration of the vehicle body and the seat due to noise can be eliminated.
Also for the mass m ₁ of the vehicle body, a difference from the standard value of the riding section mass (a value set in advance based on the assumption) is added.
In the initial stage (at the start of this control loop), the vehicle body inclination angle θ ₁ uses a design value or a value stored at the end of the previous boarding / stopping control.
In this embodiment, the influence of the riding section mass fluctuation is considered only in the vehicle body weight m _1. However, the center of gravity distance l ₁ of the vehicle body may be corrected in consideration of the influence of the riding section mass fluctuation. Good.

In the present embodiment, only the parameters that are directly affected by the riding section mass fluctuation are corrected. However, for example, the feedback gain may be corrected in consideration of the influence.
For example, the feedback gain K _S7 in Formula 3, Formula 6, Formula 11, and Formula 15 may be corrected according to Formula 18 below.
In Equation 18, the symbol [x] represents the standard value of x.

(Formula 18)
K _S7 = (m _S / [m _S ]) [K _S7 ]

When the riding section mass m _S is determined by Expression 17, the main control ECU 21 performs the processing from step 11 to step 16 in the same manner as in the first embodiment.
However, the value of the riding section mass m _S (and the vehicle body mass m ₁ ) determined in step 102 is used in Formula 2 for determining the gravity center correction position λ _{S, n} used in Formula 1.

When the center of gravity P of the vehicle main body moves on a vertical line passing through the contact point S1 of the drive wheel, the main control ECU 21 reads from the seat load meter 73 a vertical load (carrying portion load W) applied to the seat, similarly to steps 101 and 102. _S ) is obtained (step 201), and the riding section mass m _S is determined by the above equation 17 (step 202).
When the riding section mass m _S is determined by Expression 17, the main control ECU 21 performs the processing from step 21 to step 25 as in the first embodiment.
However, in Formula 5 for determining the vehicle body tilt angle target value θ ₁ ^* , the value of the riding section mass m _S (and the vehicle mass m ₁ ) determined in step 202 is used.

Next, the boarding / alighting stop control in the third embodiment will be described with reference to FIG.
The main control ECU 21 obtains the vertical load (carrying part load W _S ) acting on the seat from the seat load meter 73 (step 301), similarly to the steps 101 and 102 in the standing control, and determines the riding part mass m _S as described above. This is determined by Equation 17 (step 302).
When the riding section mass m _S is determined, the main control ECU 21 performs the processing from step 31 to step 36 as in the first embodiment.
However, in the equation for determining the center-of-gravity correction position λ _{S, n} used in Equation 8 (Equation 9) and the equation for determining the vehicle body tilt angle target value θ ₁ ^{* in} Equation 10, the riding section mass m _S (and The value of the vehicle body mass m ₁ ) is used.

When the processing from the inverted state by the loop of step 301 to step 36 to the stoppage state is completed, the main control ECU 21 performs a vertical load (acting on the seat) from the seat load meter 73 as in steps 301 and 302. The riding section load W _S ) is acquired (step 401), and the riding section mass m _S is determined by the above equation 17 (step 402).
When the riding section mass m _S is determined by Expression 17, the main control ECU 21 performs the processing from step 41 to step 45 in the same manner as in the first embodiment.
However, the value of the riding section mass m _S (and the vehicle body mass m ₁ ) determined in Step 402 is used in the determination formula (Formula 14) of the boarding / alighting assist position λ _{S, end} used in Formula 13.

  In this embodiment, in order to cope with the case where the riding section mass changes during the standing control and the getting on / off control described with reference to FIGS. 15 and 16, the riding section load is acquired every time in the control loop. Although described, the load may be measured only once before the start of the control loop. In this case, the mass change during the control cannot be dealt with, but the stability of the control can be improved.

Next, a fourth embodiment will be described.
In the third embodiment, the case where the value of the riding section mass m _S (and the vehicle body mass m ₁ ) is calculated by the mathematical expression 17 from the actual measurement value by the seat load meter 73 has been described. In the fourth embodiment, the riding section mass m _S is calculated. The mass is estimated, and the control parameter is corrected according to the estimated value. The riding section mass is estimated by, for example, a state observer.
The control system in the fourth embodiment is the same as that in the first embodiment shown in FIG.

FIG. 17 is a flowchart showing the processing contents of the standing control in the fourth embodiment.
The main control ECU 21 first estimates the riding section mass (step 103). That is, the main control ECU 21 estimates the riding section mass m _S from the seat movement state by the seat movement model of the following Expression 19. In Expression 19, S _{S, f0} is dry friction and uses a preset value. To do.
In addition, g represents a gravitational acceleration, and C _S represents a viscous friction coefficient with respect to sheet movement.
At the start of this control loop (step 101 to step 16), a predetermined standard value is given to the riding section mass as an initial value of the observer.

(Formula 19)
m _S = (− S _S ± S _{S, f 0} + C _S {λ _S }) / g sin θ ₁

In Formula 19, for example, a larger riding section mass m _S is estimated as the thrust S _S required for moving the seat is larger at a constant seat moving speed {λ _S }.
In addition, in the seat movement model according to Equation 19, inertia is not considered, and dry friction is a constant value that does not depend on weight, but the riding section mass is measured using a more detailed model that strictly considers them. m _S may be Estimated A high-frequency component may be removed by applying a low-pass filter to the riding section mass m _S obtained by Expression 19. As a result, the observer can be stabilized and vibrations of the vehicle body and the seat due to noise can be eliminated.

When the riding section mass m _S is estimated by Expression 19, the main control ECU 21 performs the processing from step 11 to step 16 in the same manner as in the first embodiment.
However, in Equation 2 for determining the center-of-gravity correction position λ _{S, n} used in Equation 1, the value of the riding section mass m _S (and the vehicle body mass m ₁ ) estimated in Step 103 is used.

When the center of gravity P of the vehicle body moves on a vertical line passing through the contact point S1 of the driving wheel, the main control ECU 21 determines the riding section mass m _S again (step 203). That is, the main control ECU 21 estimates the riding section mass m _S from the vehicle body tilt state (θ ₁ ) using the vehicle body tilt model of Equation 20.
In Equation 20, m _C is a non-fluctuating amount of the vehicle body weight and is represented by [m ₁ ] − [m _S ]. The symbol [x] represents the standard value of x.
When this control loop (step 203 to step 25) is opened, a predetermined standard value is given to the riding section mass as an initial value of the observer.

(Formula 20)
m _S = ((τ _W / g) −m _C l ₁ sin θ ₁ ) / (l ₁ sin θ ₁ + λ _S cos θ ₁ )

In Formula 20, for example, at a constant vehicle body inclination angle θ ₁ and seat position λ _S , a larger riding section mass m _S is estimated as the torque τ _W required for the vehicle body to stand up is larger.
Although the vehicle body inclination model according to Equation 20 does not consider inertia and friction, the riding section mass m _S may be estimated using a more detailed model that strictly considers these. Moreover, you may estimate from another dynamical systems, such as rotation of a driving wheel.
A high-frequency component may be removed by applying a low-pass filter to the riding section mass m _S obtained by Expression 20. As a result, the observer can be stabilized and vibrations of the vehicle body and the seat caused by noise can be suppressed.

When the riding section mass m _S is estimated by Expression 20, the main control ECU 21 performs the processing from step 21 to step 26 in the same manner as in the first embodiment.
However, in Equation 5 for determining the vehicle body tilt angle target value θ ₁ ^* , the value of the riding section mass m _S (and the vehicle body mass m ₁ ) estimated in step 203 is used.

FIG. 18 is a flowchart showing the processing contents of the boarding / alighting stop control in the fourth embodiment.
The main control ECU 21 first estimates the riding section mass (step 303). For this estimation, the vehicle body tilt model of Formula 20 described in the standing control of the fourth embodiment is used.
Next, the main control ECU 21 performs the processing from step 31 to step 36 as in the first embodiment.
However, in the equation for determining the center-of-gravity correction position λ _{S, n} used in Equation 8 (Equation 9) and the equation for determining the vehicle body tilt angle target value θ ₁ ^{* in} Equation 10, the riding section mass m _S ( The value of the vehicle body mass m ₁ ) is used.

When the processing from the inverted state by the loop from step 303 to step 36 is completed, the main control ECU 21 determines the riding section mass m _S (step 403). For this estimation, the seat movement model of Equation 19 described in the standing control of the fourth embodiment is used.
Next, the main control ECU 21 performs the processing from step 41 to step 45 in the same manner as in the first embodiment.
However, the riding section mass m _S estimated in Step 403 is used in the determination formula (Formula 14) of the boarding / alighting assist position λ _{S, end} used in Formula 13.

In the stand-up control and the boarding / alighting stop control of the fourth embodiment described above, the riding section mass m _S is estimated in the same loop (same period) as the control loop, but is estimated in another loop (period). May be. For example, when the calculation amount is large, the period of the estimation calculation may be increased.

In the fourth embodiment, the riding section mass m _S is estimated by an observer based on a mechanical model, but a simpler method may be used. For example, instead of Equation 19, the result of measuring the relationship between the minimum thrust required to move the seat and the riding section mass m _S at that time is stored in advance as a map, and the estimation is performed using it. May be.

In the third embodiment and the fourth embodiment described above, the riding section mass m _S in the first embodiment is determined by measurement and estimation, respectively. In the second embodiment, in the third embodiment and the fourth embodiment. The determined and estimated riding section mass m _S may be used.

Further, in each of the above-described embodiments, the inclination direction of the vehicle main body in the state where the vehicle stops getting on and off is forward, but, for example, when the riding part has no backrest and only the seat surface part, or rides from behind without the seat surface part. In the case of a vehicle configured as described above, the vehicle may be inclined backward.
Moreover, you may make it employ | adopt the following structure as a vehicle.
(1) Configuration 1 A vehicle that travels while maintaining a vehicle body including a riding portion and a vehicle body in an inverted state by controlling torque of the drive wheel according to a tilt state of the vehicle body and a rotation state of the drive wheel. A limiting mechanism that limits a tilt angle of the vehicle body by being partly grounded, a riding portion moving mechanism that moves the riding portion in the front-rear direction of the vehicle with respect to the vehicle body, and a center of gravity of the vehicle body is the The vehicle body is tilted until the boarding portion is moved to the rear side by the riding portion moving mechanism so as to be positioned on a vertical line passing through the grounding point of the drive wheel until the boarding / stopping state where a part of the restriction mechanism is grounded. There is provided a vehicle characterized by comprising a boarding / alighting stop control means.
(2) Configuration 2 The vehicle according to Configuration 1, wherein the boarding / alighting stop control unit moves the riding section forward after the boarding / alighting stop.
(3) Configuration 3 The boarding / alighting stop control means determines a boarding part target position of the boarding part and a vehicle body inclination angle target value according to an elapsed time from the start of tilting for the boarding / alighting stop, and the boarding The vehicle according to Configuration 1 or Configuration 2, wherein the vehicle state is feedback-controlled according to a target position, and the vehicle tilt state is feedback-controlled according to the vehicle body tilt angle target value. ,I will provide a.
(4) Configuration 4 The configuration 1, the configuration 2, or the configuration 3 according to the configuration 1, the configuration 2, or the configuration 3, wherein the boarding / alighting stop control unit determines that the boarding / alighting stop state is present when the vehicle body inclination angular velocity is equal to or less than a predetermined threshold. Vehicle.
(5) Configuration 5: The vehicle according to Configuration 3, further comprising load acquisition means for acquiring a load acting on the riding section, and determining the riding section target position according to the acquired load. provide.
(6) Configuration 6 The load acquisition means includes at least a measurement value obtained by a load meter that measures a load mounted on the riding section, or a moving state of the riding section, an inclined state of the vehicle body, and a rotation state of the driving wheel. The vehicle according to Configuration 5, wherein an estimated value by a state observer using one is used as a load acting on the riding section.
According to the above configuration, since the center of gravity of the vehicle body is positioned on a vertical line passing through the grounding point of the driving wheel, the vehicle body is inclined to stop getting on and off while moving the riding portion backward. It is possible to incline to stop getting on and off without moving the vehicle.

It is explanatory drawing showing the state of the vehicle in the standing-up control and boarding / alighting stop control by this embodiment. It is the figure which illustrated the external appearance structure of the state which is drive | working ahead about the vehicle in this embodiment. It is a block diagram of the control system in 1st Embodiment and 4th Embodiment. It is a flowchart showing the main flow of standing-up / alighting stop control. It is a flowchart showing the processing content of standing control in 1st Embodiment. FIG. 6 is an explanatory diagram showing temporal changes in a seat position target value λ _S ^* and a vehicle body tilt angle target value θ ₁ ^* in standing control. It is a flowchart showing the processing content of the boarding / alighting stop control in 1st Embodiment. FIG. 6 is an explanatory diagram showing temporal changes of a seat position target value λ _S ^* and a vehicle body tilt angle target value θ ₁ ^{* in} the getting-on / off stop control. It is a block diagram of the control system in 2nd Embodiment. It is a figure showing each structural example of the balancer moving mechanism. It is a dynamic model figure of the vehicle attitude control system in the second embodiment. It is a flowchart showing the processing content of standing control in 2nd Embodiment. It is a flowchart showing the processing content of the boarding / alighting stop control in 2nd Embodiment. It is a block diagram of the control system in 3rd Embodiment. It is a flowchart showing the processing content of standing control in 3rd Embodiment. It is a flowchart showing the processing content of the boarding / alighting stop control in 3rd Embodiment. It is a flowchart showing the processing content of standing control in 4th Embodiment. It is a flowchart showing the processing content of the boarding / alighting stop control in 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Drive wheel 12 Drive motor 13 Riding part 14 Support member 131 Seat surface part 132 Backrest part 133 Headrest 16 Control unit 17 Stopper 20 Control ECU
21 Main control ECU
22 Drive wheel control ECU
23 Balancer control ECU
24 Seat control ECU
30 Input device 31 Control device 32 Start / Get off switch 40 Car body control system 41 Angle meter 50 Drive wheel control system 51 Drive wheel rotation angle meter 52 Drive wheel actuator 60 Balancer control system 61 Balancer drive motor rotation angle meter 62 Balancer drive actuator (motor )
70 seat control system 71 seat drive motor rotation angle meter 72 seat drive actuator 73 seat load meter 134 balancer 135 slider type actuator 136 support shaft 137, 138 balancer support shaft motor

Claims (7)

By controlling the torque of the drive wheel according to the tilt state of the vehicle body and the rotation state of the drive wheel, the vehicle travels while holding the vehicle body including the riding section and the vehicle body in an inverted state,
A limiting mechanism that limits the inclination angle of the vehicle body by partially grounding at the time of stopping;
A riding section moving mechanism that moves the riding section in the longitudinal direction of the vehicle with respect to the vehicle body;
Standing control means for raising the vehicle main body while moving the riding portion forward by the riding portion moving mechanism so that the center of gravity of the vehicle main body is located on a vertical line passing through the ground point of the drive wheel;
A vehicle characterized by comprising:   The standing control means moves the riding section until the center of gravity of the vehicle body is located on a vertical line passing through the ground point of the driving wheel in a state where the inclination angle of the vehicle body is limited by the limiting mechanism. The vehicle according to claim 1, wherein the vehicle main body starts to stand.   The standing-up control means determines whether or not the riding section has moved until the center of gravity of the vehicle main body is located on a vertical line passing through the grounding point of the drive wheel, based on a change in the inclination angle of the vehicle main body. The vehicle according to claim 2, wherein the vehicle is a vehicle.   The standing control means determines a riding section target position of the riding section and a vehicle body inclination angle target value according to an elapsed time from the start of standing, and a movement state of the riding section according to the riding section target position 4. The vehicle according to claim 1, wherein the vehicle is subjected to feedback control, and the tilt state of the vehicle body is feedback-controlled according to the vehicle body tilt angle target value. 5.   The standing control means determines the riding section target position and the vehicle body tilt angle target value so that the standing speed at the start of standing up and when the standing up is completed are smaller than the standing speed during the standing up. The vehicle according to claim 4. A load acquisition means for acquiring a load acting on the riding section;
The vehicle according to claim 4, wherein the riding section target position is determined according to the acquired load. The load acquisition means uses at least one of a measurement value obtained by a load meter that measures a load mounted on the riding section, or a moving state of the riding section, an inclined state of the vehicle body, and a rotating state of the driving wheel. The vehicle according to claim 6 , wherein an estimated value obtained by a state observer is a load acting on the riding section.

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