JP2011068224A - Inverted pendulum type moving body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverted pendulum type moving body capable of maintaining the attitude of a base body, even when a gravity center point is moved. <P>SOLUTION: The inverted pendulum type moving body includes the base body 2, a moving operation part constituted of a plurality of wheels 3 (4) including an omnidirectionaly moving wheel capable of being omnidirectionaly driven on a floor surface, a relative driving part for relatively moving at least one of the plurality of wheels 3 (4) in relation to the base body 2, an inclination detecting part 52 for detecting an inclined angle and change amount of the inclined angle of the base body 2, and a control part 50 for outputting a driving command to the relative driving part according to the inclined angle and the change amount of the inclined angle. When the inclination detecting part 52 detects inclination of the base body 2, the control part 50 relatively moves at least one of the plurality of wheels 3 (4) in relation to the base body 2 by driving the relative driving part according to the detected inclination and locates the gravity center point on a straight line connecting each center position of the moving operation part provided in each of the plurality of wheels 3 (4) or the inside of a polygonal shape connecting each center position of the moving operation part provided in each of the plurality of wheels 3 (4). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an inverted pendulum type moving body having a plurality of wheels.

  As the omnidirectional vehicle that can move in all directions (two-dimensional omnidirectional) on the floor surface, for example, those shown in Patent Documents 1 and 2 have been proposed by the present applicant. In the omnidirectional mobile vehicle found in these Patent Documents 1 and 2, a spherical or wheel-like or crawler-like moving operation unit capable of moving in all directions on the floor surface while being in contact with the floor surface; An actuator device having an electric motor or the like for driving the moving operation unit is assembled to a vehicle body. And this vehicle moves on a floor surface by driving a movement operation part with an actuator device.

  Further, as a technique for controlling the moving operation of this type of omnidirectional vehicle, for example, a technique found in Patent Document 3 has been proposed by the present applicant. In this technique, a vehicle base is provided so as to be tiltable in the front-rear and left-right directions with respect to a spherical moving operation unit. Then, the vehicle is moved according to the tilting motion of the base by measuring the tilt angle of the base and controlling the torque of the electric motor that drives the moving operation unit so as to keep the tilt angle at a required angle. I have to.

International Publication No. 08/132778 Pamphlet International Publication No. 08/1327979 Pamphlet Japanese Patent No. 3070015

By the way, in a moving body that performs inverted pendulum control in only one direction, if the center of gravity moves in the direction from directly above the ground point (or wheel rotation center), the wheel moves according to the amount of movement of the center of gravity. The base is inclined so that the center of gravity is returned to the position just above the grounding point.
However, when a load or the like is placed on the base body of the mobile body, the base body is inclined due to the above-described characteristics, and thus there is a problem that the placed load slips off. In addition, when the base body is tilted, the posture of the occupant is also tilted, and there is a problem that the riding comfort is deteriorated.
In addition, there is a base balancer that moves the balancer in accordance with the tilt of the base to relieve the tilt of the base. However, there is a problem that the weight of the base increases.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an inverted pendulum type moving body capable of maintaining the posture of the base body even when the center of gravity is moved. And

  In order to solve the above problem, the invention described in claim 1 is a plurality of wheels (e.g., an embodiment) including a base and an omnidirectional wheel attached to the base and capable of driving in all directions on the floor surface. A moving operation unit (for example, the actuator 422 in the embodiment), a relative drive unit that relatively moves at least one of the plurality of wheels with respect to the base, and A tilt detection unit (for example, the tilt sensor 52 in the embodiment) that detects the tilt angle and the change amount of the tilt angle, and a drive command (for example, the tilt angle and the change amount of the tilt angle to the relative drive unit) A control unit (for example, the control unit 50 in the embodiment) that outputs a slider drive command in the embodiment, and when the predetermined condition is satisfied, Parts are inverted pendulum type moving body, wherein the position of at least one wheel of the tilt angle of the plurality so as to approach a predetermined value wheel of the substrate be moved relative to the substrate. Thereby, the control part can move a wheel relatively with respect to a base | substrate according to the inclination of a base | substrate, when predetermined conditions are satisfied.

  The invention described in claim 2 includes a base body and a plurality of wheels (for example, the wheel 3 and the wheel 4 in the embodiment) including an omnidirectional moving wheel attached to the base body and capable of being driven in all directions on the floor surface. A moving operation unit, a relative drive unit (for example, the actuator 422 in the embodiment) that relatively moves at least one of the plurality of wheels with respect to the base body, an inclination angle of the base body, and a change in the inclination angle A tilt detection unit that detects the amount (for example, the tilt sensor 52 in the embodiment) and a drive command (for example, a slider drive command in the embodiment) to the relative drive unit according to the tilt angle and the amount of change in the tilt angle. And a control unit (for example, the control unit 50 in the embodiment). The control unit detects when the tilt detection unit detects the tilt of the substrate. By driving the relative drive unit according to the tilt, at least one of the plurality of wheels is relatively moved with respect to the base body, and the center position of the moving operation unit of each of the plurality of wheels is connected. It is an inverted pendulum type moving body characterized in that the center of gravity is located on a straight line or inside a polygon that connects the center positions of the moving operation portions of each of the plurality of wheels. Thus, the control unit drives the relative drive unit according to the detected tilt when detecting the tilt of the base, and the relative drive unit moves the wheel relative to each other, thereby moving the wheel according to the tilt.

  According to a third aspect of the present invention, the inverted pendulum type moving body has a load sensor that detects a change in load applied to the base body, and the control unit detects a change in load by the load sensor. In this case, the relative driving unit is driven. The load sensor detects a change in load acting on the base, and the control unit can drive the relative drive unit when the change in load is detected.

  According to a fourth aspect of the present invention, when the control unit relatively moves at least one omnidirectional moving wheel among the plurality of wheels by the relative driving unit, an amount by which the relative driving unit relatively moves the wheel. The wheel is driven by the moving operation unit in the same amount and direction as the direction. Thereby, when the wheel is relatively moved, the frictional force generated between the floor surface and the wheel can be reduced.

According to the first aspect of the present invention, when the predetermined condition is satisfied, the control unit can move the wheel relative to the base in accordance with the tilt of the base. The inclination of the substrate can be set to a predetermined value by driving the part. As a result, it is possible to maintain the levelness of the base body, and to prevent a load placed on the base body from slipping down or deteriorating riding comfort.
According to the second aspect of the present invention, the control unit drives the relative drive unit according to the detected tilt when detecting the tilt of the base body, and the relative drive unit relatively moves the wheels, thereby depending on the tilt. Since the wheel can be moved, even when the center of gravity moves, the center position of the moving operation unit can be determined by driving the relative driving unit to move the center position of the moving operation unit of each of the plurality of wheels. By positioning the barycentric point directly above the connecting straight line, the level of the base can be maintained without tilting the base. As a result, it is possible to prevent the load placed on the base from slipping down and the ride comfort from being deteriorated.
According to the invention described in claim 3, the load sensor detects a change in the load acting on the base body, and the control unit can drive the relative drive unit when the change in the load is detected. It is possible to detect the case where the base body is inclined by placing a load or the like on the base body, and to maintain the level of the base body. Further, when the inverted pendulum type moving body is running, when the base body is inclined due to the movement of the center of gravity of the occupant, the operation feeling of the inverted pendulum type moving body is impaired by not driving the relative drive unit. Can be prevented.
According to the fourth aspect of the present invention, when the wheels are moved relative to each other, the frictional force generated between the floor and the wheels can be reduced, so that the orientation of the base body changes as the wheels move. Can be prevented. As a result, the horizontality of the base body can be maintained without impairing the operational feeling of the inverted pendulum type moving body due to the relative movement of the wheels.

It is the perspective view which looked at the electric vehicle in the embodiment of the present invention from the front side. It is the perspective view which looked at the electric vehicle in embodiment of this invention from the rear side. It is an expanded sectional view of a rear wheel. It is a perspective view of a rear wheel. It is a perspective view of a wheel body. It is a figure which shows the arrangement | positioning relationship between a wheel body and a free roller. It is a simplified diagram showing the relationship between the center of gravity of the electric vehicle and the wheel body in the embodiment. It is a flowchart which shows the process of the control unit of the electric vehicle of embodiment. It is a figure which shows the inverted pendulum model expressing the dynamic behavior of the electric vehicle of embodiment. It is a block diagram which shows the processing function regarding the process of FIG.8 S9. It is a block diagram which shows the processing function of the gain adjustment part shown in FIG. It is a block diagram which shows the processing function of the limit process part (or limit process part shown in FIG. 13) shown in FIG. It is a block diagram which shows the processing function of the gravity center speed restriction | limiting part 76 shown in FIG. It is a block diagram which shows the processing function of the attitude | position control calculating part 80 shown in FIG. It is a flowchart which shows the process of the attitude | position calculation calculating part 80 shown in FIG. It is a simplified diagram showing the relationship between the center of gravity of the electric vehicle and the wheel body in a modification of the embodiment. It is a simplified diagram showing the relationship between the center of gravity of the electric vehicle and the wheel body in a modification of the embodiment. It is a simplification figure showing the composition of the slider mechanism in the modification of an embodiment.

Embodiments of the present invention will be described below. First, the structure of an inverted pendulum type moving body having omnidirectional driving wheels in this embodiment will be described with reference to FIGS.
FIG. 1 is a perspective view of an electric vehicle viewed from the front side, and FIG. 2 is a perspective view of the electric vehicle viewed from the rear side.
As shown in FIGS. 1 and 2, the electric vehicle 1 of the present embodiment includes a base body 2, front wheels (second wheels) 3 and rear wheels (first wheels) that are omnidirectional drive wheels attached to the front and rear of the base body 2. Wheel) 4 and a seating portion 7 disposed above the rear wheel 4 and capable of seating the occupant (user) D forward of the electric vehicle 1.
The front wheel 3 and the rear wheel 4 move in all directions (two-dimensional all directions including the front-rear direction (first direction) and the left-right direction (second direction)) while touching the floor surface. And an actuator device 19 for driving the movable movement unit 5R.

  Here, in the description of the present embodiment, “front-rear direction” and “left-right direction” respectively match or substantially coincide with the front-rear direction and the left-right direction of the upper body of the occupant who has boarded the seat portion 7 in a standard posture. Means direction. Note that the “standard posture” is a posture assumed by design with respect to the seating portion 7, and the trunk axis of the occupant's upper body is generally directed vertically and the upper body is not twisted. It is posture. Further, in the description of the present embodiment, the suffixes “R” and “L” attached to the reference numerals are used to mean the right side and the left side of the electric vehicle 1, respectively.

The base body 2 includes a step floor 9 formed so as to bridge between the front wheel 3 and the rear wheel 4, a front wheel fender 11F and a rear wheel fender 11R constituting the front wheel 3 and the rear wheel 4, a rear wheel fender 11R and a seating portion. 7 is provided.
The step floor 9 is a flat plate-like member extending in parallel with the road surface T with a space between the step surface T, and is configured so that a foot portion, luggage, etc. of the occupant D can be placed on the upper surface thereof. ing. The front wheel fender 11F of the front wheel 3 is connected to the front end of the step floor 9, while the rear wheel fender 11R of the rear wheel 4 is connected to the rear end.
The connecting portion 10 is a columnar member extending upward, and the lower end is connected to the upper portion of the rear wheel fender 11R, and the seating portion 7 is connected to the upper end.

  The seating portion 7 includes a seat portion 12 that is L-shaped in side view for the passenger D to get on, and a base portion 14 that connects the seat portion 12 and the connecting portion 10 described above. The seat portion 12 extends in the front-rear direction to support the occupant D's buttocks and thighs, and the seat portion 12 extends upward from the rear end portion of the seat surface portion 13 to support the back of the occupant D. The seat back 15 is provided.

  A pair of armrests 16 extending from the middle in the height direction toward the front are provided at both left and right ends of the seat back 15. The armrests 16 are supported so as to be rotatable about a pitch axis (an axis orthogonal to the front-rear direction) with respect to the seat back 15. A controller 6 for steering the movement operation of the electric vehicle 1 with the hand of the occupant D is installed at the tip of the armrest 16. A handrail 18 extending in the left-right direction is provided at the upper end portion of the seat back 15, and a baggage such as a bag can be hooked on the handrail 18. In addition, on the rear side of the seat back 15, a collapsible loading platform 17 is provided. The loading platform 17 is supported on the lower end side of the seat back 15 so as to be tiltable around the pitch axis. Specifically, the loading platform 17 is arranged so as to extend substantially parallel to the seat back 15 when not in use (see FIG. 2), and tilts to a position substantially orthogonal to the seat back 15 when in use. (Refer to FIG. 1), a load or the like can be placed on the upper surface thereof.

  The base portion 14 has an upper end portion connected to the lower surface of the seat surface portion 13, and a lower end portion connected to the upper end of the connection portion 10 via a drive mechanism (not shown). And the seating part 5 is comprised by the drive mechanism so that rotation around the yaw axis (normal line of the road surface T (refer FIG. 3)) is possible (refer arrow M in FIG. 1).

FIG. 3 is an enlarged cross-sectional view of the rear wheel, and FIG. 4 is a perspective view of the rear wheel. FIG. 5 is a perspective view of the wheel body, and FIG. 6 is a diagram showing an arrangement relationship between the wheel body and the free roller. Since both the front wheel and the rear wheel have the same configuration, the following description will be made taking the rear wheel as an example.
As shown in FIG. 3, a long rail 41 is provided inside the rear wheel fender 11 </ b> R, and a wheel support member 42 joined to the rear wheel 4 is penetrated by the rail 41 and the electric vehicle 1. Are slidably supported in the left-right direction (Y direction). Inside the wheel support member 42 are provided an actuator 422 fixed to the inner surface of the wheel member 42 by a fixing member 421 and a roller 423 that rotates when the actuator 422 is driven. The roller 423 is in pressure contact with the rail 41, and the wheel support member 42 moves in the Y direction along the rail 41 when the actuator 422 is driven. That is, the electric vehicle 1 has a slider function for moving the position of the rear wheel 4 in the Y direction by driving the actuator 422.

As shown in FIGS. 3 to 6, the rear wheel 4 has a wheel body 5R formed in an annular shape by a rubber-like elastic material or the like, and the wheel body 5R has a substantially circular cross-sectional shape. Due to the elastic deformation of the wheel body 5R, as indicated by the arrow Y1 in FIGS. 5 and 6, the wheel body 5R passes through the center C1 of the circular cross section (specifically, through the circular cross section center C1). It can be rotated around a circumference line that is concentric with the axis.
The wheel body 5R is disposed inside the cover member 21 with its axis C2 (axis C2 perpendicular to the diameter direction of the entire wheel body 5R) aligned with the left-right direction of the electric vehicle 1, and the wheel body 5R It is in contact with the road surface T at the lower end of the outer peripheral surface. The cover member 21 is a dome-shaped member that is formed in a circular shape in a side view and opens downward, and is disposed so as to cover almost the entire portion except the lower end portion of the rear wheel 4.

The wheel body 5R rotates around the axis C2 of the wheel body 5R as shown by an arrow Y2 in FIG. 5 (operation that rotates on the road surface T) by driving by the actuator device 19 (details will be described later). ) And an operation of rotating around the cross-sectional center C1 of the wheel body 5R. As a result, the wheel body 5R can move in all directions on the road surface T by a combined operation of these rotational operations.
The actuator device 19 is provided between the rotating member 27R and the free roller 29R interposed between the wheel body 5R and the right side wall 21R of the cover member 21, and between the wheel body 5R and the left side wall 21L of the cover member 21. Rotating member 27L and free roller 29L, electric motor 31R as an actuator disposed above rotating member 27R and free roller 29R, and electric motor as an actuator disposed above rotating member 27L and free roller 29L 31L.

The electric motors 31 </ b> R and 31 </ b> L are respectively attached to the side walls 21 </ b> R and 21 </ b> L of the cover member 21. Although illustration is omitted, the power sources (capacitors) of the electric motors 31 </ b> R and 31 </ b> L are mounted at appropriate positions on the base 2.
The rotating member 27R is rotatably supported on the right side wall 21R via a support shaft 33R having a horizontal axis. Similarly, the rotating member 27L is rotatably supported by the left side wall 21L via a support shaft 33L having a left-right axis. In this case, the rotation axis of the rotation member 27R (axis of the support shaft 33R) and the rotation axis of the rotation member 27L (axis of the support shaft 33L) are coaxial.

The rotating members 27R and 27L are connected to the output shafts of the electric motors 31R and 31L via power transmission mechanisms including functions as speed reducers, respectively, and the power (torque) transmitted from the electric motors 31R and 31L, respectively. It is rotationally driven by. Each power transmission mechanism is of a pulley-belt type, for example. That is, as shown in FIG. 3, the rotating member 27R is connected to the output shaft of the electric motor 31R via the pulley 35R and the belt 37R. Similarly, the rotating member 27L is connected to the output shaft of the electric motor 31L via a pulley 35L and a belt 37L.
The power transmission mechanism described above may be constituted by, for example, a sprocket and a link chain, or constituted by a plurality of gears. In addition, for example, the electric motors 31R and 31L are arranged to face the rotating members 27R and 27L so that the respective output shafts are coaxial with the rotating members 27R and 27L. The output shaft may be connected to each of the rotating members 27R and 27L via a reduction gear (such as a planetary gear device).

Each rotating member 27R, 27L is formed in the same shape as a truncated cone that is reduced in diameter toward the wheel body 5R side, and its outer peripheral surface is a tapered outer peripheral surface 39R, 39L.
A plurality of free rollers 29R are arranged around the tapered outer peripheral surface 39R of the rotating member 27R so as to be arranged at equal intervals on a circumference concentric with the rotating member 27R. Each of these free rollers 29R is attached to the tapered outer peripheral surface 39R via a bracket 38R and is rotatably supported by the bracket 38R.
Similarly, a plurality (the same number as the free rollers 29R) of free rollers 29L are arranged around the tapered outer peripheral surface 39L of the rotating member 27L so as to be arranged at equal intervals on a circumference concentric with the rotating member 27L. Yes. Each of these free rollers 29L is attached to the tapered outer peripheral surface 39L via a bracket 38L and is rotatably supported by the bracket 38L.

The wheel body 5R is disposed coaxially with the rotating members 27R and 27L so as to be sandwiched between the free roller 29R on the rotating member 27R side and the free roller 29L on the rotating member 27L side.
In this case, as shown in FIG. 6, each free roller 29R, 29L has its axis C3 inclined with respect to the axis C2 of the wheel body 5R and the diameter direction of the wheel body 5R (the wheel body 5R is the axis When viewed in the direction of the center C2, it is arranged in a posture inclined with respect to the axial center C2 and the radial direction connecting the free rollers 29R and 29L. In such a posture, the outer peripheral surfaces of the free rollers 29R and 29L are in pressure contact with the inner peripheral surface of the wheel body 5R in an oblique direction.
More generally speaking, the free roller 29R on the right side is a frictional force component in the direction around the axis C2 at the contact surface with the wheel body 5R when the rotating member 27R is driven to rotate around the axis C2. (The frictional force component in the tangential direction of the inner periphery of the wheel body 5R) and the frictional force component in the direction around the center C1 of the cross section of the wheel body 5R (the frictional force component in the tangential direction of the circular cross section) In such a posture that it can act on the wheel body 5R, it is pressed against the inner peripheral surface of the wheel body 5R. The same applies to the left free roller 29L.

The front wheel 3 has the same configuration as the rear wheel 4 described above, and the front wheel 3 and the rear wheel 4 are arranged such that the axis (rotation axis) C2 of the wheel body 5R is parallel to each other ( 1 and 2). When the rotating members 27R and 27L are driven to rotate at the same speed in the same direction by the electric motors 31R and 31L of the front wheel 3 and the rear wheel 4, respectively, each wheel body 5R has the same direction as the rotating members 27R and 27L. Will rotate around the axis C2. Thereby, each wheel body 5R rotates on the road surface T in the front-rear direction, and the entire electric vehicle 1 moves in the front-rear direction. In this case, the wheel body 5R does not rotate around the center C1 of the cross section.
Further, for example, when the rotating members 27R and 27L are rotationally driven in the opposite directions at the same speed, each wheel body 5R rotates around the center C1 of the cross section. As a result, each wheel body 5R moves in the direction of the axis C2 (that is, in the left-right direction), and as a result, the entire electric vehicle 1 moves in the left-right direction. In this case, the wheel body 5R does not rotate around the axis C2.

Further, when the rotating members 27R and 27L are driven to rotate in different directions (speeds including directions) in the same direction or in the opposite direction, each wheel body 5R rotates around its axis C2. At the same time, it will rotate around its cross-sectional center C1.
At this time, the wheel body 5R moves in a direction inclined with respect to the front-rear direction and the left-right direction by a combined operation (combining operation) of these rotational operations, and as a result, the entire electric vehicle 1 is in the same direction as the wheel body 5R. Will move. The moving direction of the wheel body 5R in this case changes depending on the difference between the rotational speeds (rotational speed vectors whose polarities are defined according to the rotational direction) including the rotational direction of the rotating members 27R and 27L. .
Since each wheel body 5R is moved as described above, the rotational speeds (including the rotational direction) of the electric motors 31R and 31L are controlled, and consequently the rotational speeds of the rotating members 27R and 27L are controlled. Thus, the moving speed and moving direction of the electric vehicle 1 can be controlled.

  Here, schematic operation control of the electric vehicle 1 will be described. Basically, in the electric vehicle 1 of the present embodiment, when the occupant D seated on the seat portion 12 tilts the upper body (specifically, When the upper body is tilted so as to move the position of the center of gravity G of the entire occupant D and the electric vehicle 1 (position projected on the horizontal plane), the base body 2 is seated on the side where the upper body is tilted. Tilt with. At this time, the movement operation of the wheel body 5R is controlled so that the electric vehicle 1 moves to the side on which the base body 2 is inclined. That is, in the present embodiment, the operation of the occupant D moving the upper body and, in turn, tilting the base body 2 together with the seat portion 12 is one basic maneuvering operation (operation request of the electric vehicle 1) with respect to the electric vehicle 1. The moving operation of the wheel body 5R is controlled via the actuator device 19 in accordance with the steering operation.

  Specifically, the center of gravity G of the electric vehicle 1 (and the entire occupant D) of the base body 2 in a state where the center of gravity G is located almost directly above the straight line connecting the center point of the front wheel 3 and the center point of the rear wheel 4. The movement operation of the front wheels 3 and the rear wheels 4 is controlled so that the posture is a target posture and basically the actual posture of the base 2 is converged to the target posture. That is, the movement operation of the front wheels 3 and the rear wheels 4 is controlled so that the vertical direction of the electric vehicle 1 coincides with the direction of gravity. Specifically, when it is determined that the center of gravity G has moved in the front-rear direction with respect to the target posture, the wheel body 5R of the front wheel 3 and the rear wheel 4 described above is rotated around the axis C2, and the electric vehicle 1 Is moved back and forth. On the other hand, when it is determined that the center of gravity G has moved in the left-right direction with respect to the target posture, each wheel body 5R is rotated around the center C1 to move the electric vehicle 1 in the left-right direction. Or the attitude | position of the base | substrate 2 is converged to a target attitude | position by the combined operation | movement of these rotation operation | movement. Therefore, when the electric vehicle 1 is desired to be moved, the center of gravity of the occupant D is inclined toward the traveling direction. Then, the electric vehicle 1 moves in the traveling direction so as to maintain the target posture. The movement operation of the electric vehicle 1 can also be controlled by steering the controller 6 that is grounded to the armrest 16.

Further, as shown in FIG. 7B, when the center of gravity G moves leftward with respect to the base body 2 by placing a load on the base body 2, for example, the step floor 9, the front wheel fender 11F and the rear wheel fender The base body 2 is controlled to be prevented from tilting in the Y direction by driving the wheel body 5R and the actuator 422 provided in each of the wheel bodies 5R by the slider mechanism provided in 11R.
Specifically, the center of gravity G is located almost directly above the straight line connecting the center point of the wheel body 5F and the wheel body 5R (center point on the axis C2) (more precisely, the center of gravity point is the wheel The target position is a state where the body 5F and the wheel body 5R are located almost directly above the straight line connecting the ground contact surfaces, and the actual posture of the base body 2 is the target posture (in this embodiment, the base body 2 and the seating portion 7 are The slider mechanism, that is, the actuator 422 is controlled so as to converge to an attitude that maintains the level.
FIG. 7A is a simplified diagram showing the relationship between the center of gravity G of the electric vehicle 1 and the wheel bodies 5F and 5R in the embodiment. FIG. 7 (b) is a simplified diagram showing the relationship between the wheel body 5 </ b> F and the outside wheel 5 </ b> R when the barycentric point G moves leftward with respect to the base 2.

In the present embodiment, in order to perform the operation control of the electric vehicle 1 as described above, as shown in FIG. 1 and FIG. The occupant boarded the control unit 50, the inclination sensor 52 for measuring the inclination angle θb of the predetermined part of the base 2 with respect to the vertical direction (the direction of gravity) and its change rate (= dθb / dt), and the vehicle 1. A rotary sensor 56R, 56L as an angle sensor for detecting the rotational angle and rotational angular velocity of the output shafts of the electric motors 31R, 31L, respectively. Installed in place.
In this case, the control unit 50 and the inclination sensor 52 are attached in the state accommodated in the inside of the connection part 10, for example. Further, the load sensor 54 is built in the seat surface portion 13 of the seat portion 12. The rotary encoders 56R and 56L are provided integrally with the electric motors 31R and 31L, respectively. The rotary encoders 56R and 56L may be attached to the rotating members 27R and 27L, respectively.

More specifically, the tilt sensor 52 includes an acceleration sensor and a rate sensor (angular velocity sensor) such as a gyro sensor, and outputs detection signals of these sensors to the control unit 50. Then, the control unit 50 executes a predetermined measurement calculation process (this may be a known calculation process) based on the outputs of the acceleration sensor and the rate sensor of the tilt sensor 52, and thereby the part on which the tilt sensor 52 is mounted. The measured value of the tilt angle θb with respect to the vertical direction (the connecting portion 10 in the present embodiment) and the measured value of the tilt angular velocity θbdot, which is the rate of change (differential value), are calculated.
In this case, the tilt angle θb to be measured (hereinafter also referred to as the base body tilt angle θb) is more specifically, the component θb_x in the Y axis direction (pitch direction) and the X axis direction (roll direction), respectively. It consists of component θb_y. Similarly, the measured tilt angular velocity θbdot (hereinafter also referred to as the base tilt angular velocity θbdot) is also measured in the Y-axis direction (pitch direction) component θbdot_x (= dθb_x / dt) and the X-axis direction (roll direction). Component θbdot_y (= dθb_y / dt).

In the description of the present embodiment, a variable such as a motion state quantity having a component in each direction of the X axis and the Y axis (or a direction around each axis) such as the base body inclination angle θb, or a relation to the motion state quantity. For a variable such as a coefficient to be processed, a suffix “_x” or “_y” is added to the reference symbol of the variable when each component is expressed separately.
In this case, for a variable related to translational motion such as translational speed, a subscript “_x” is added to the component in the X-axis direction, and a subscript “_y” is added to the component in the Y-axis direction.
On the other hand, for variables related to rotational motion, such as angle, rotational speed (angular velocity), angular acceleration, etc., the subscript “_x” is added to the component around the Y axis for convenience in order to align the subscript with the variable related to translational motion. In addition, the subscript “_y” is added to the component around the X axis.

Further, when a variable is expressed as a set of a component in the X-axis direction (or a component around the Y-axis) and a component in the Y-axis direction (or a component around the X-axis), the reference number of the variable The subscript “_xy” is added. For example, when the base body tilt angle θb is expressed as a set of a component θb_x around the Y axis and a component θb_y around the X axis, it is expressed as “base body tilt angle θb_xy”.
The load sensor 54 is built in the seat 7 so as to receive a load due to the weight of the occupant when the occupant is seated on the seat 7, and outputs a detection signal corresponding to the load to the control unit 50. Then, the control unit 50 determines whether or not an occupant is on the vehicle 1 based on the measured load value indicated by the output of the load sensor 54.

Instead of the load sensor 54, for example, a switch type sensor that is turned on when an occupant sits on the seating portion 7 may be used.
The rotary encoder 56R generates a pulse signal every time the output shaft of the electric motor 31R rotates by a predetermined angle, and outputs this pulse signal to the control unit 50. Then, the control unit 50 measures the rotational angle of the output shaft of the electric motor 53R based on the pulse signal, and further calculates the temporal change rate (differential value) of the measured value of the rotational angle as the rotational angular velocity of the electric motor 53R. Measure as The same applies to the rotary encoder 56L on the electric motor 31L side.

The control unit 50 executes a predetermined calculation process using each measurement value described above, thereby determining a speed command that is a target value of the rotational angular speed of each of the electric motors 31R and 31L, and in accordance with the speed command, the electric motor The rotational angular velocities of 31R and 31L are feedback controlled.
The relationship between the rotational angular velocity of the output shaft of the electric motor 31R and the rotational angular velocity of the rotating member 27R is proportional to the constant reduction ratio between the output shaft and the rotating member 27R. In the description of this embodiment, for the sake of convenience, the rotational angular velocity of the electric motor 31R means the rotational angular velocity of the rotating member 27R. Similarly, the rotational angular velocity of the electric motor 31L means the rotational angular velocity of the rotating member 27L.

Hereinafter, the control process of the control unit 50 will be described in more detail.
The control unit 50 executes the process (main routine process) shown in the flowchart of FIG. 8 at a predetermined control process cycle.
First, in step S <b> 1, the control unit 50 acquires the output of the tilt sensor 52.
Next, the process proceeds to step S2, and the control unit 50 calculates the measured value θb_xy_s of the base body tilt angle θb and the measured value θbdot_xy_s of the base body tilt angular velocity θbdot based on the acquired output of the tilt sensor 52.
In the following description, when an observed value (measured value or estimated value) of an actual value of a variable (state quantity) such as the measured value θb_xy_s is represented by a reference sign, the reference sign of the variable is subscripted. Add “_s”.
Moreover, since the electric vehicle 1 shown in the present embodiment has a two-wheeled vehicle configuration, the description of the rotational component in the Y-axis direction may be ignored in the following description. That is, θb_x_s and θbdot_x_s may always be regarded as 0.

Next, in step S3, the control unit 50 acquires the output of the load sensor 54, and then executes the determination process in step S4. In this determination process, the control unit 50 determines whether or not an occupant is on the vehicle 1 depending on whether or not the load measurement value indicated by the acquired output of the load sensor 54 is larger than a predetermined value set in advance ( Whether or not an occupant is seated in the seating portion 7).
If the determination result in step S4 is affirmative, the control unit 50 sets a target value θb_xy_obj for the base body tilt angle θb, and constant parameters for controlling the operation of the vehicle 1 (basic values for various gains). Etc.) are set in steps S5 and S6, respectively.

In step S5, the control unit 50 sets a predetermined target value for the boarding mode as the target value θb_xy_obj of the base body tilt angle θb.
Here, the “boarding mode” means an operation mode of the vehicle 1 when an occupant is on the vehicle 1. In this boarding mode target value θb_xy_obj, the overall center of gravity of the vehicle 1 and the occupant seated on the seat 7 (hereinafter referred to as the vehicle / occupant overall center of gravity) connects the center positions of the wheel body 5F and the wheel pair 5R. In the posture of the base body 2 that is positioned almost directly above the straight line, it is set in advance so as to coincide with or substantially coincide with the measured value θb_xy_s of the base body tilt angle θb measured based on the output of the tilt sensor 52.

In step S <b> 6, the control unit 50 sets a predetermined value for the boarding mode as a constant parameter value for controlling the operation of the vehicle 1. The constant parameters are hx, hy, Ki_a_x, Ki_b_x, Ki_a_y, Ki_b_y (i = 1, 2, 3), which will be described later.
On the other hand, if the determination result in step S4 is negative, the control unit 50 sets the target parameter θb_xy_obj of the base body tilt angle θb_xy and sets the constant parameter value for controlling the operation of the vehicle 1. Are executed in steps S7 and S8.
In step S7, the control unit 50 sets a predetermined target value for the independent mode as the target value θb_xy_obj of the inclination angle θb.

Here, the “self-supporting mode” means an operation mode of the vehicle 1 when no occupant is on the vehicle 1. The target value θb_xy_obj for the self-supporting mode is an inclination sensor in the posture of the base body 2 in a state where the center of gravity of the vehicle 1 (hereinafter referred to as the vehicle center of gravity) is located almost directly above the ground contact surface of the wheel body 5. It is set in advance so as to coincide with or substantially coincide with the measured value θb_xy_s of the base body tilt angle θb measured based on the output of 52. The target value θb_xy_obj for the self-supporting mode is generally different from the target value θb_xy_obj for the boarding mode.
In step S <b> 8, the control unit 50 sets a predetermined value for the independent mode as a constant parameter value for controlling the operation of the vehicle 1. The value of the constant parameter for the independent mode is different from the value of the constant parameter for the boarding mode.

The difference in the value of the constant parameter between the boarding mode and the independent mode is due to the difference in the height of the center of gravity, the overall mass, etc. in each mode, and the response of the operation of the vehicle 1 to the control input. This is because the characteristics are different from each other.
Through the processes in steps S4 to S8 described above, the target value θb_xy_obj of the base body tilt angle θb_xy and the value of the constant parameter are set individually for each operation mode of the boarding mode and the independent mode.
Note that it is not essential to execute the processes of steps S5 and S6 or the processes of steps S7 and S8, and may be executed only when the determination result of step S4 changes.

Supplementally, in both the boarding mode and the self-supporting mode, the target value of the component θbdot_x around the Y axis and the target value of the component θbdot_y around the X axis of the base body tilt angular velocity θbdot are both “0”. For this reason, the process which sets the target value of base | substrate inclination angular velocity (theta) bdot_xy is unnecessary.
After executing the processing of steps S5 and S6 or the processing of steps S7 and 8 as described above, the control unit 50 next executes the vehicle control arithmetic processing in step S9, whereby each of the electric motors 31R and 31L is executed. Determine the speed command. Details of the vehicle control calculation process will be described later.

Next, the process proceeds to step S10, and the control unit 50 executes an operation control process for the electric motors 31R and 31L according to the speed command determined in step S9. In this operation control process, the control unit 50 determines the difference between the speed command of the electric motor 31R determined in step S9 and the measured value of the rotational speed of the electric motor 31R measured based on the output of the rotary encoder 56R. The target value (target torque) of the output torque of the electric motor 31R is determined so that the deviation converges to “0”. Then, the control unit 50 controls the energization current of the electric motor 31R so that the output torque of the target torque is output to the electric motor 31R. The same applies to the operation control of the left electric motor 31L.
The above is the overall control process executed by the control unit 50.

Next, details of the vehicle control calculation process in step S9 will be described.
In the following description, the vehicle / occupant overall center-of-gravity point in the boarding mode and the vehicle single body center-of-gravity point in the autonomous mode are collectively referred to as a vehicle system center-of-gravity point. When the operation mode of the vehicle 1 is the boarding mode, the vehicle system center-of-gravity point means the vehicle / occupant overall center-of-gravity point, and when it is in the self-supporting mode, it means the vehicle single body center-of-gravity point.
In the following description, regarding the value (value to be updated) determined by the control unit 50 in each control processing cycle, the value determined in the current (latest) control processing cycle is the current value, and the control processing immediately before that The value determined by the cycle may be referred to as the previous value. A value not particularly different from the current value and the previous value means the current value.
Further, regarding the speed and acceleration in the X-axis direction, the forward direction is a positive direction, and regarding the speed and acceleration in the Y-axis direction, the left direction is a positive direction.

In the present embodiment, the dynamic behavior of the center of gravity of the vehicle system (specifically, the behavior seen by projecting from the Y-axis direction onto a plane (XZ plane) orthogonal thereto, and orthogonal to the X-axis direction) As shown in FIG. 9, the behavior of the inverted pendulum model (the dynamic behavior of the inverted pendulum) is approximately expressed as Vehicle control calculation processing is performed.
In FIG. 9, reference numerals without parentheses are reference numerals corresponding to the inverted pendulum model viewed from the Y-axis direction, and reference numerals with parentheses refer to the inverted pendulum model viewed from the X-axis direction. Corresponding reference sign.

In this case, the inverted pendulum model expressing the behavior seen from the Y-axis direction has a mass point 60_x located at the center of gravity of the vehicle system and a rotation axis 62a_x parallel to the Y-axis direction. Wheel 62_x (hereinafter referred to as virtual wheel 62_x). The mass point 60_x is supported by the rotation shaft 62a_x of the virtual wheel 62_x via the linear rod 64_x, and can swing around the rotation shaft 62a_x with the rotation shaft 62a_x as a fulcrum.
In this inverted pendulum model, the motion of the mass point 60_x corresponds to the motion of the vehicle system center of gravity as viewed from the Y-axis direction. In addition, the inclination angle θbe_x of the rod 64_x with respect to the vertical direction coincides with the deviation θbe_x_s (= θb_x_s−θb_x_obj) between the measured base body tilt angle value θb_x_s and the base body tilt angle target value θb_x_obj in the direction around the Y axis. Further, the changing speed (= dθbe_x / dt) of the inclination angle θbe_x of the rod 64_x is set to coincide with the measured body inclination angular velocity θbdot_x_s in the direction around the Y axis. Further, the movement speed Vw_x (translation movement speed in the X-axis direction) of the virtual wheel 62_x is the same as the movement speed in the X-axis direction of the wheel body 5 of the vehicle 1.

Similarly, an inverted pendulum model (refer to the reference numerals in parentheses in FIG. 9) expressing the behavior seen from the X-axis direction includes a mass point 60_y located at the center of gravity of the vehicle system and a rotation axis 62a_y parallel to the X-axis direction. And a virtual wheel 62_y (hereinafter referred to as a virtual wheel 62_y) that can rotate on the floor surface. The mass point 60_y is supported by the rotation shaft 62a_y of the virtual wheel 62_y via a linear rod 64_y, and can swing around the rotation shaft 62a_y with the rotation shaft 62a_y as a fulcrum.
In this inverted pendulum model, the motion of the mass point 60_y corresponds to the motion of the vehicle system center-of-gravity point viewed from the X-axis direction. Further, the inclination angle θbe_y of the rod 64_y with respect to the vertical direction coincides with the deviation θbe_y_s (= θb_y_s−θb_y_obj) between the measured base body tilt angle value θb_y_s and the base body tilt angle target value θb_y_obj in the direction around the X axis. In addition, the change speed (= dθbe_y / dt) of the inclination angle θbe_y of the rod 64_y coincides with the measured body inclination angular velocity θbdot_y_s in the direction around the X axis. Further, the moving speed Vw_y (translational moving speed in the Y-axis direction) of the virtual wheel 62_y matches the moving speed in the Y-axis direction of the wheel body 5 of the vehicle 1.

The virtual wheels 62_x and 62_y have predetermined radii of predetermined values Rw_x and Rw_y, respectively.
Further, the rotational angular velocities ωw_x and ωw_y of the virtual wheels 62_x and 62_y and the rotational angular velocities ω_R and ω_L of the electric motors 31R and 31L (more precisely, the rotational angular velocities ω_R and ω_L of the rotating members 27R and 27L), respectively. The relationship of the following formulas 01a and 01b is established.

ωw_x = (ω_R + ω_L) / 2 Equation 01a
ωw_y = C · (ω_R−ω_L) / 2 …… Formula 01b

Note that “C” in the expression 01b is a coefficient of a predetermined value depending on the mechanical relationship between the free rollers 29R and 29L and the wheel body 5 and slippage.
Here, the dynamics of the inverted pendulum model shown in FIG. 9 is expressed by the following equations 03x and 03y. The expression 03x is an expression expressing the dynamics of the inverted pendulum model viewed from the Y-axis direction, and the expression 03y is an expression expressing the dynamics of the inverted pendulum model viewed from the X-axis direction.

d ² θbe_x / dt ² = α_x · θbe_x + β_x · ωwdot_x ...... Formula 03x
d ² θbe_y / dt ² = α_y · θbe_y + β_y · ωwdot_y ...... Formula 03y

In equation 03x, ωwdot_x is the rotational angular acceleration of the virtual wheel 62_x (first-order differential value of the rotational angular velocity ωw_x), α_x is a coefficient that depends on the mass and height h_x of the mass 60_x, and β_x is the inertia (moment of inertia of the virtual wheel 62_x ) And the radius Rw_x. The same applies to ωwdot_y, α_y, and β_y in Expression 03y.
As can be seen from these equations 03x and 03y, the motions of the mass points 60_x and 60_y of the inverted pendulum (and hence the motion of the center of gravity of the vehicle system) are the rotational angular acceleration ωwdot_x of the virtual wheel 62_x and the rotational angular acceleration ωwdot_y of the virtual wheel 62_y, respectively. It is defined depending on.

  Therefore, in the present embodiment, the rotational angular acceleration ωwdot_x of the virtual wheel 62_x is used as an operation amount (control input) for controlling the motion of the vehicle system center of gravity point viewed from the Y-axis direction, and viewed from the X-axis direction. The rotational angular acceleration ωwdot_y of the virtual wheel 62_y is used as an operation amount (control input) for controlling the motion of the vehicle system center of gravity.

  The vehicle control arithmetic processing in step S9 will be described schematically. The control unit 50 determines that the motion of the mass point 60_x seen in the X-axis direction and the motion of the mass point 60_y seen in the Y-axis direction are the vehicle system center of gravity. Virtual wheel rotational angular acceleration commands ωwdot_x_cmd and ωwdot_y_cmd, which are command values (target values) of the rotational angular accelerations ωwdot_x and ωwdot_y as the operation amounts, are determined so as to correspond to the desired motion. Further, the control unit 50 integrates the virtual wheel rotation angular acceleration commands ωwdot_x_cmd and ωwdot_y_cmd, and the virtual wheel rotation that is the command values (target values) of the respective rotation angular velocities ωw_x and ωw_y of the virtual wheels 62_x and 62_y. The angular velocity commands are determined as ωw_x_cmd and ωw_y_cmd.

Then, the control unit 50 moves the virtual wheel 62_x corresponding to the virtual wheel rotational angular velocity command ωw_x_cmd (= Rw_x · ωw_x_cmd) and the virtual wheel 62_y corresponding to the virtual wheel rotational angular velocity command ωw_y_cmd (= Rw_y · ωw_y_cmd). ) As the target movement speed in the X-axis direction and the target movement speed in the Y-axis direction of the wheel body 5 of the vehicle 1, and the respective speeds of the electric motors 31 </ b> R and 31 </ b> L so as to realize these target movement speeds. The commands ω_R_cmd and ω_L_cmd are determined.
In this embodiment, the virtual wheel rotation angular acceleration commands ωwdot_x_cmd and ωwdot_y_cmd as the operation amount (control input) are obtained by adding three operation amount components as shown in equations 07x and 07y described later, respectively. It is determined.

The control unit 50 performs the vehicle control calculation process in step S9 in order to perform the control as described above for the front wheel 3 and the rear wheel 4, respectively, and performs the function shown in the block diagram of FIG. Individually. Note that the calculations performed on the front wheel 3 and the rear wheel 4 are the same.
As shown in the figure, the control unit 50 includes a deviation calculating unit 70 that calculates a base body tilt angle deviation measured value θbe_xy_s that is a deviation between the base body tilt angle measured value θb_xy_s and the base body tilt angle target value θb_xy_obj, and the vehicle system center-of-gravity point. It is requested by a center-of-gravity speed calculation unit 72 that calculates a center-of-gravity speed estimated value Vb_xy_s as an observed value of the center-of-gravity speed Vb_xy that is a moving speed, and a maneuvering operation of the vehicle 1 by an occupant or the like (an operation that adds propulsive force to the vehicle 1). The required center-of-gravity speed generation unit 74 that generates the required center-of-gravity speed Vb_xy_aim as the required value of the center-of-gravity speed Vb_xy estimated to be, and the rotation of the electric motors 31R and 31L from the estimated center-of-gravity speed Vb_xy_s A gravity center speed limiter 76 for determining a control target gravity center speed Vb_xy_mdfd as a target value of the gravity center speed Vb_xy in consideration of a restriction according to the allowable range of the angular velocity, A gain adjustment unit 78 for determining a gain adjustment parameter Kr_xy for adjusting the gain coefficient values of the expressions 07x and 07y to be described, a slider control unit 75 for determining a slider command value for controlling the slider, and a control target And an addition operation unit 77 that corrects the center-of-gravity velocity Vb_xy_mdfd.

The control unit 50 further calculates the virtual wheel rotation angular velocity command ωw_xy_cmd, the attitude control calculation unit 80, and the virtual wheel rotation angular velocity command ωw_xy_cmd from the speed command ω_R_cmd (rotational angular velocity command value) of the right electric motor 31R. And a motor command calculation unit 82 for converting into a set with a speed command ω_L_cmd (rotation angular velocity command value) of the left electric motor 31L.
The control unit 50 also includes a slider command calculation unit 85 that converts the slider command value calculated by the slider control unit 75 into a slider drive command S_cmd for the actuator 422.
The reference numeral 84 in FIG. 10 indicates a delay element for inputting the virtual wheel rotation angular velocity command ωw_xy_cmd calculated by the attitude control calculation unit 80 for each control processing cycle. The delay element 84 outputs the previous value ωw_xy_cmd_p of the virtual wheel rotation angular velocity command ωw_xy_cmd in each control processing cycle.

The slider control unit 75 includes a deviation calculation unit 751, a slider operation switching unit 752, a first-order lag filter 753, a sign inverting unit 754, a limiter 755, processing units 756 and 758, and a low-pass filter 757. Yes.
The deviation calculator 751 calculates a deviation between the center-of-gravity speed estimated value Vb_xy_s calculated by the center-of-gravity speed calculator 72 and the value output by the limiter 755, and outputs the deviation to the slider operation switching unit 752. The slider operation switching unit 752 switches between a mode in which the slider operation is performed and a mode in which the slider operation is not performed in accordance with a switching signal input from the outside. Further, the slider operation switching unit 752 outputs the deviation input from the deviation calculating unit 751 to the temporary delay filter 753 in the case of the slider operation mode, and in the mode of performing the slider operation, 0 (zero) is the primary delay. Output to the filter 753. That is, in the mode in which the slider operation is not performed, the slider control unit 75 does not perform control for driving the actuator 422 of the slider mechanism.

First-order lag filter 753 filters the change in value input from slider operation switching section 752 and outputs the result to sign inverting section 754. The sign inversion unit 754 inverts the sign of the input value and outputs the result to the limiter 755. The limiter 755 outputs the input value to the processing unit 756 when the input value is within the range between a predetermined upper limit value (> 0) and a lower limit value (<0). When the input value exceeds the upper limit value, the upper limit value is output to the processing unit 756, and when the input value is smaller than the lower limit value, the lower limit value is output.
The processing unit 756 outputs a slider command value that is a value obtained by multiplying the input value by the fourth gain coefficient K 4 to the low-pass filter 757 and the slider command calculation unit 85. The low pass filter 757 performs a filtering process on the input value (slider command value) and outputs the result to the processing unit 758. The processing unit 758 calculates a control target center-of-gravity velocity correction value Vb_y_cancel_cmd, which is a value obtained by multiplying the value input from the low-pass filter 757 by the fifth gain coefficient K5, and outputs the calculated value to the addition calculation unit 77. In the present embodiment, since the moving direction of the wheel bodies 5F and 5R by the slider mechanism is only in the Y direction, the control target center-of-gravity velocity correction value Vb_y_cancel_cmd is only in the Y direction component.

In the vehicle control calculation process in step S9, the processes of the above-described respective processing units are executed as described below.
That is, the control unit 50 first executes the process of the deviation calculating unit 70 and the process of the gravity center speed calculating unit 72.
The deviation calculation unit 70 receives the base body tilt angle measurement value θb_xy_s (θb_x_s and θb_y_s) calculated in step S2 and the target values θb_xy_obj (θb_x_obj and θb_y_obj) set in step S5 or step S7. . Then, the deviation calculating unit 70 subtracts θb_x_obj from θb_x_s to calculate a measured body tilt angle deviation value θbe_x_s (= θb_x_s−θb_x_obj) around the Y axis, and subtracts θb_y_obj from θb_y_s to obtain X A base body tilt angle deviation measurement value θbe_y_s (= θb_y_s−θb_y_obj) in the direction around the axis is calculated.
The process of the deviation calculation unit 70 may be performed before the vehicle control calculation process in step S9. For example, you may perform the process of the deviation calculating part 70 in the process of the said step S5 or 7.

The center-of-gravity velocity calculation unit 72 receives the current value of the base body tilt angular velocity measurement value θbdot_xy_s (θbdot_x_s and θbdot_y_s) calculated in step S2 and the previous value ωw_xy_cmd_p (ωw_x_cmd_p and ωw_y_cmd_p) of the virtual wheel speed command ωw_xy_cmd. Is input from the delay element 84. Then, the center-of-gravity speed calculation unit 72 calculates the center-of-gravity speed estimated values Vb_xy_s (Vb_x_s and Vb_y_s) from these input values using a predetermined arithmetic expression based on the inverted pendulum model.
Specifically, the center-of-gravity velocity calculation unit 72 calculates Vb_x_s and Vb_y_s by the following equations 05x and 05y, respectively.

Vb_x_s = Rw_x · ωw_x_cmd_p + h_x · θbdot_x_s ...... Formula 05x
Vb_y_s = Rw_y · ωw_y_cmd_p + h_y · θbdot_y_s …… Formula 05y

  In these expressions 05x and 05y, Rw_x and Rw_y are the respective radii of the virtual wheels 62_x and 62_y as described above, and these values are predetermined values set in advance. H_x and h_y are the heights of the mass points 60_x and 60_y of the inverted pendulum model, respectively. In this case, in the present embodiment, the height of the vehicle system center-of-gravity point is maintained substantially constant. Therefore, predetermined values set in advance are used as the values of h_x and h_y, respectively. Supplementally, the heights h_x and h_y are included in the constant parameters whose values are set in step S6 or 8.

The first term on the right side of the formula 05x is the moving speed in the X-axis direction of the virtual wheel 62_x corresponding to the previous value ωw_x_cmd_p of the speed command of the virtual wheel 62_x, and this moving speed is the X-axis direction of the wheel body 5 This corresponds to the current value of the actual movement speed. Further, the second term on the right side of the expression 05x is the moving speed in the X-axis direction of the vehicle system center-of-gravity point caused by tilting the base body 2 at the inclination angular velocity of θbdot_x_s around the Y-axis (relative to the wheel body 5). This is equivalent to the current value of the movement speed. The same applies to Formula 05y.
It should be noted that a set of measured values (current values) of the rotational angular velocities of the electric motors 31R and 31L measured based on the outputs of the rotary encoders 56R and 56L is used as a set of rotational angular velocities of the virtual wheels 62_x and 62_y. The rotational angular velocities may be converted and used in place of ωw_x_cmd_p and ωw_y_cmd_p in equations 05x and 05y. However, it is advantageous to use the target values ωw_x_cmd_p and ωw_y_cmd_p in order to eliminate the influence of noise included in the measured value of the rotational angular velocity.

Next, the control unit 50 executes the processing of the required center-of-gravity velocity generation unit 74 and the processing of the gain adjustment unit 78. In this case, the center-of-gravity speed estimation value Vb_xy_s (Vb_x_s and Vb_y_s) calculated by the center-of-gravity speed calculation unit 72 as described above is input to the required center-of-gravity speed generation unit 74 and the gain adjustment unit 78, respectively.
Then, when the operation mode of the vehicle 1 is the boarding mode, the required center-of-gravity speed generation unit 74 calculates the required center-of-gravity speed Vb_xy_aim (Vb_x_aim, Vb_y_aim) based on the input center-of-gravity speed estimated value Vb_xy_s (Vb_x_s and Vb_y_s). decide. In the present embodiment, when the operation mode of the vehicle 1 is the self-supporting mode, the requested center-of-gravity speed generation unit 74 sets both the requested center-of-gravity speeds V_x_aim and V_y_aim to “0”.

Further, the gain adjustment unit 78 determines the gain adjustment parameter Kr_xy (Kr_x and Kr_y) based on the input center-of-gravity velocity estimation value Vb_xy_s (Vb_x_s and Vb_y_s).
The processing of the gain adjustment unit 78 will be described below with reference to FIGS.
As shown in FIG. 11, the gain adjustment unit 78 inputs the input center-of-gravity velocity estimated values Vb_x_s and Vb_y_s to the limit processing unit 86. In the limit processing unit 86, output values Vw_x_lim1 and Vw_y_lim1 are generated by appropriately adding limits corresponding to the allowable ranges of the rotational angular velocities of the electric motors 31R and 31L to the gravity center speed estimated values Vb_x_s and Vb_y_s. The output value Vw_x_lim1 has a meaning after limiting the moving speed Vw_x in the X-axis direction of the virtual wheel 62_x, and the output value Vw_y_lim1 has a meaning as a value after limiting the moving speed Vw_y in the Y-axis direction of the virtual wheel 62_y. .

The processing of the limit processing unit 86 will be described in more detail with reference to FIG. Note that the reference numerals in parentheses in FIG. 11 indicate processing of the limit processing unit 104 of the gravity center speed limiting unit 76 described later, and may be ignored in the description of the processing of the limit processing unit 86.
First, the limit processing unit 86 inputs the center-of-gravity velocity estimated values Vb_x_s and Vb_y_s to the processing units 86a_x and 86a_y, respectively. The processing unit 86a_x divides Vb_x_s by the radius Rw_x of the virtual wheel 62_x to calculate the rotational angular velocity ωw_x_s of the virtual wheel 62_x when it is assumed that the moving speed in the X-axis direction of the virtual wheel 62_x matches Vb_x_s. . Similarly, the processing unit 86a_y calculates the rotational angular velocity ωw_y_s (= Vb_y_s / Rw_y) of the virtual wheel 62_y when it is assumed that the moving speed of the virtual wheel 62_y in the Y-axis direction matches Vb_y_s.

Next, the limit processing unit 86 converts the set of ωw_x_s and ωw_y_s into a set of the rotation angular velocity ω_R_s of the electric motor 31R and the rotation angular velocity ω_L_s of the electric motor 31L by the XY-RL conversion unit 86b.
In this embodiment, in this embodiment, simultaneous equations obtained by substituting ωw_x, ωw_y, ω_R, and ω_L in equations 01a and 01b with ωw_x_s, ωw_y_s, ω_R_s, and ω_L_s, respectively, are solved by using ω_R_s and ω_L_s as unknowns. Done.
Next, the limit processing unit 86 inputs the output values ω_R_s and ω_L_s of the XY-RL conversion unit 86b to the limiters 86c_R and 86c_L, respectively. At this time, if the limiter 86c_R is within the allowable range for the right motor having a predetermined upper limit value (> 0) and lower limit value (<0), the limiter 86c_R keeps ω_R_s as it is. Output as output value ω_R_lim1. Further, when ω_R_s deviates from the allowable range for the right motor, the limiter 86c_R outputs the boundary value closer to ω_R_s between the upper limit value and the lower limit value of the allowable range for the right motor as the output value ω_R_lim1. Output as. As a result, the output value ω_R_lim1 of the limiter 86c_R is limited to a value within the allowable range for the right motor.

Similarly, when the limiter 86c_L is within the allowable range for the left motor having a predetermined upper limit value (> 0) and lower limit value (<0), the limiter 86c_L keeps ω_L_s as it is. Output as output value ω_L_lim1. Further, when ω_L_s deviates from the left motor allowable range, the limiter 86c_L outputs the boundary value closer to ω_L_s between the upper limit value and the lower limit value of the left motor allowable range as the output value ω_L_lim1. Output as. As a result, the output value ω_L_lim1 of the limiter 86c_L is limited to a value within the allowable range for the left motor.
The allowable range for the right motor is set so that the rotational angular velocity (absolute value) of the right electric motor 31R does not become too high, and in turn prevents the maximum value of torque that can be output by the electric motor 31R from decreasing. Tolerance. The same applies to the allowable range for the left motor.

Next, the limit processing unit 86 converts the set of output values ω_R_lim1 and ω_L_lim1 of the limiters 86c_R and 86c_L into sets of rotational angular velocities ωw_x_lim1 and ωw_y_lim1 of the virtual wheels 62_x and 62_y by the RL-XY conversion unit 86d. .
This conversion is a reverse conversion process of the conversion process of the XY-RL conversion unit 86b. This processing is performed by solving simultaneous equations obtained by replacing ωw_x, ωw_y, ω_R, and ω_L in the equations 01a and 01b with ωw_x_lim1, ωw_y_lim1, ω_R_lim1, and ω_L_lim1, with ωw_x_lim1 and ωw_y_lim1 as unknowns.
Next, the limit processing unit 86 inputs the output values ωw_x_lim1 and ωw_y_lim1 of the RL-XY conversion unit 86d to the processing units 86e_x and 86e_y, respectively. The processing unit 86e_x converts ωw_x_lim1 into the moving speed Vw_x_lim1 of the virtual wheel 62_x by multiplying ωw_x_lim1 by the radius Rw_x of the virtual wheel 62_x. Similarly, the processor 86e_y converts ωw_y_lim1 into the moving speed Vw_y_lim1 (= ωw_y_lim1 · Rw_y) of the virtual wheel 62_y.

  It is assumed that the movement speed Vw_x of the virtual wheel 62_x in the X-axis direction and the movement speed Vw_y of the virtual wheel 62_y in the Y-axis direction are made to coincide with the center-of-gravity speed estimated values Vb_x_s and Vb_y_s, respectively, by the above processing of the limit processing unit 86. In other words (in other words, assuming that the moving speed in the X-axis direction and the moving speed in the Y-axis direction of the wheel body 5 are respectively matched with Vb_x_s and Vb_y_s), it is necessary to realize those moving speeds. When the rotational angular velocities ω_R_s and ω_L_s of the electric motors 31R and 31L are both within the allowable range, a set of output values Vw_x_lim1 and Vw_y_lim1 that respectively match Vb_x_s and Vb_y_s is obtained from the limit processing unit 86. Is output.

On the other hand, when both or one of the rotational angular velocities ω_R_s and ω_L_s of the electric motors 31R and 31L deviate from the allowable range, both or one of the rotational angular velocities is forcibly limited within the allowable range. Thus, the limit processing unit 86 outputs a set of movement speeds Vw_x_lim1 and Vw_y_lim1 in the X-axis direction and the Y-axis direction corresponding to the set of rotational angular velocities ω_R_lim1 and ω_L_lim1 of the electric motors 31R and 31L after the limitation.
Therefore, the limit processing unit 86 can make the rotation angular velocities of the electric motors 31R and 31L corresponding to the set of the output values Vw_x_lim1 and Vw_y_lim1 not to deviate from the permissible range under the necessary conditions. As long as the output values Vw_x_lim1 and Vw_y_lim1 coincide with Vb_x_s and Vb_y_s, a set of output values Vw_x_lim1 and Vw_y_lim1 is generated.

Returning to the description of FIG. 11, the gain adjustment unit 78 next executes the processing of the calculation units 88_x and 88_y. The calculation unit 88_x receives the estimated center-of-gravity velocity value Vb_x_s in the X-axis direction and the output value Vw_x_lim1 of the limit processing unit 86. Then, the calculation unit 88_x calculates and outputs a value Vover_x obtained by subtracting Vb_x_s from Vw_x_lim1. Further, the Y-axis direction center of gravity velocity estimated value Vb_y_s and the output value Vw_y_lim1 of the limit processing unit 86 are input to the arithmetic unit 88_y. The computing unit 88_y calculates and outputs a value Vover_y obtained by subtracting Vb_y_s from Vw_y_lim1.
In this case, if the output values Vw_x_lim1 and Vw_y_lim1 are not forcibly limited by the limit processing unit 86, Vw_x_lim1 = Vb_x_s and Vw_y_lim1 = Vb_y_s, and thus the output values Vover_x of the arithmetic units 88_x and 88_y, respectively. , Vover_y is “0”.

On the other hand, when the output values Vw_x_lim1 and Vw_y_lim1 of the limit processing unit 86 are generated by forcibly limiting the input values Vb_x_s and Vb_y_s, the correction amount (= Vw_x_lim1−Vb_x_s) of Vw_x_lim1 from Vb_x_s , And Vw_y_lim1 are corrected from Vb_y_s (= Vw_y_lim1-Vb_y_s) from the arithmetic units 88_x and 88_y, respectively.
Next, the gain adjustment unit 78 determines the gain adjustment parameter Kr_x by sequentially passing the output value Vover_x of the calculation unit 88_x through the processing units 90_x and 92_x. Further, the gain adjustment unit 78 determines the gain adjustment parameter Kr_y by sequentially passing the output value Vover_y of the calculation unit 88_y through the processing units 90_y and 92_y. The gain adjustment parameters Kr_x and Kr_y are both values in the range from “0” to “1”.

The processing unit 90_x calculates and outputs the absolute value of the input Vover_x. Further, the processing unit 92_x generates Kr_x so that the output value Kr_x monotonously increases with respect to the input value | Vover_x | and has a saturation characteristic. The saturation characteristic is a characteristic in which the change amount of the output value with respect to the increase of the input value becomes “0” or approaches “0” when the input value increases to some extent.
In this case, in this embodiment, when the input value | Vover_x | is equal to or smaller than a predetermined value set in advance, the processing unit 92_x sets a value obtained by multiplying the input value | Vover_x | by a proportional coefficient of the predetermined value. Output as Kr_x. In addition, when the input value | Vover_x | is larger than a predetermined value, the processing unit 92_x outputs “1” as Kr_x. The proportional coefficient is set such that the product of | Vover_x | and the proportional coefficient is “1” when | Vover_x | matches a predetermined value.
The processing of the processing units 90_y and 92_y is the same as the processing of the above-described processing units 90_x and 92_x, respectively.

  When the output values Vw_x_lim1 and Vw_y_lim1 are not forcibly limited by the limit processing unit 86 by the processing of the gain adjusting unit 78 described above, that is, in the X axis direction and the Y axis direction of the wheel body 5 respectively. Even if the electric motors 31R and 31L are operated so that the movement speeds Vw_x and Vw_y coincide with the center-of-gravity speed estimated values Vb_x_s and Vb_y_s, the respective rotational angular velocities of the electric motors 31R and 31L are within the allowable range. In this case, the gain adjustment parameters Kr_x and Kr_y are both determined to be “0”.

  On the other hand, when the output values Vw_x_lim1 and Vw_y_lim1 of the limit processing unit 86 are generated by forcibly limiting the input values Vb_x_s and Vb_y_s, that is, in the X axis direction and the Y axis direction of the wheel body 5 respectively. If the electric motors 31R and 31L are operated so that the moving speeds Vw_x and Vw_y coincide with the center-of-gravity speed estimated values Vb_x_s and Vb_y_s, respectively, the rotational angular speed of either of the electric motors 31R and 31L deviates from the allowable range. In the case (when the absolute value of one of the rotational angular velocities becomes too high), the gain adjustment parameters Kr_x and Kr_y are determined according to the absolute values of the correction amounts Vover_x and Vover_y, respectively. In this case, Kr_x is determined so that the larger the absolute value of the correction amount Vx_over, with “1” as the upper limit value, the larger the value. The same applies to Kr_y.

Returning to the description of FIG. 10, the control unit 50 executes the processes of the center-of-gravity speed calculation unit 72 and the requested center-of-gravity speed generation unit 74 as described above, and then executes the process of the center-of-gravity speed limiter 76.
The center-of-gravity speed limiter 76 includes an estimated center-of-gravity speed value Vb_xy_s (Vb_x_s and Vb_y_s) calculated by the center-of-gravity speed calculator 72, and a requested center-of-gravity speed Vb_xy_aim (Vb_x_aim and Vb_y_aim) determined by the required center-of-gravity speed generator 74. Is entered. Then, the center-of-gravity speed limiter 76 uses these input values to determine the control target center-of-gravity speed V_xy_mdfd (V_x_mdfd and V_y_mdfd) by executing the processing shown in the block diagram of FIG.
Specifically, the center-of-gravity speed limiting unit 76 first executes the processes of the steady deviation calculating units 94_x and 94_y.
In this case, the steady-state deviation calculating unit 94_x receives the estimated center-of-gravity velocity value Vb_x_s in the X-axis direction and the previous value Vb_x_mdfd_p of the control target center-of-gravity velocity Vb_x_mdfd in the X-axis direction via the delay element 96_x. . The steady deviation calculating unit 94_x first inputs the input Vb_x_s to the proportional / differential compensation element (PD compensation element) 94a_x. The proportional / differential compensation element 94_x is a compensation element whose transfer function is represented by 1 + Kd · S, and is obtained by multiplying the input Vb_x_s and its differential value (time change rate) by a predetermined coefficient Kd. Add the value and output the result of the addition.

Next, the steady deviation calculation unit 94_x calculates a value obtained by subtracting the input Vb_x_mdfd_p from the output value of the proportional / differential compensation element 94_x by the calculation unit 94b_x, and then outputs the output value of the calculation unit 94b_x to the phase compensation It inputs into the low-pass filter 94c_x which has a function. The low-pass filter 94c_x is a filter whose transfer function is represented by (1 + T2 · S) / (1 + T1 · S). Then, the steady deviation calculating unit 94_x outputs the output value Vb_x_prd of the low pass filter 94c_x.
In addition, the steady-state deviation calculating unit 94_y receives the Y-axis centroid speed estimated value Vb_y_s and the previous value Vb_y_mdfd_p of the Y-axis control target centroid speed Vb_y_mdfd via the delay element 96_y.

Then, similarly to the above-described steady deviation calculation unit 94_x, the steady deviation calculation unit 94_y sequentially executes the processing of the proportional / differential compensation element 94a_y, the calculation unit 94b_y, and the low-pass filter 94c_y, and outputs the output value Vb_y_prd of the low-pass filter 94c_y. To do.
Here, the output value Vb_x_prd of the steady deviation calculating unit 94_x is based on the current motion state of the vehicle system center of gravity point viewed from the Y-axis direction (in other words, the motion state of the mass point 60_x of the inverted pendulum model viewed from the Y-axis direction). It has a meaning as a steady deviation with respect to the control target center-of-gravity speed Vb_x_mdfd of the predicted predicted center-of-gravity speed estimated value in the X-axis direction. Similarly, the steady deviation calculating unit 94_y output value Vb_y_prd is estimated from the current motion state of the vehicle system center of gravity point viewed from the X-axis direction (in other words, the motion state of the mass point 60_y of the inverted pendulum model viewed from the X-axis direction). The convergence predicted value of the estimated Y-axis centroid speed estimated value in the future has a meaning as a steady deviation with respect to the control target centroid speed Vb_y_mdfd. Hereinafter, the respective output values Vb_x_prd and Vb_y_prd of the steady deviation calculating units 94_x and 94_y are referred to as center-of-gravity velocity steady deviation prediction values.

The center-of-gravity speed limiter 76 executes the processes of the steady-state deviation calculators 94_x and 94_y as described above, and then adds the requested center-of-gravity speed Vb_x_aim to the output value Vb_x_prd of the steady-state deviation calculator 94_x and the steady-state deviation calculator 94_y. Processing for adding the requested center-of-gravity velocity Vb_y_aim to the output value Vb_y_prd is executed by the calculation units 98_x and 98_y, respectively.
Therefore, the output value Vb_x_t of the calculation unit 98_x is a speed obtained by adding the required center-of-gravity speed Vb_x_aim in the X-axis direction to the center-of-gravity speed steady-state deviation predicted value Vb_x_prd in the X-axis direction. Similarly, the output value Vb_y_t of the calculation unit 98_y is a speed obtained by adding the requested center-of-gravity speed Vb_y_aim in the Y-axis direction to the center-of-gravity speed steady-state deviation predicted value Vb_y_prd in the Y-axis direction.
When the required gravity center speed Vb_x_aim in the X-axis direction is “0”, such as when the operation mode of the vehicle 1 is the self-sustained mode, the calculation unit 98_x maintains the center-of-gravity speed steady-state deviation predicted value Vb_x_prd in the X-axis direction as it is. Output value Vb_x_t. Similarly, when the required center-of-gravity speed Vb_y_aim in the Y-axis direction is “0”, the predicted center-of-gravity speed deviation deviation value Vb_y_prd in the Y-axis direction is directly used as the output value Vb_y_t of the calculation unit 98_y.

Next, the center-of-gravity speed limiting unit 76 inputs the output values Vb_x_t and Vb_y_t of the calculation units 98_x and 98_y to the limit processing unit 100, respectively. The processing of the limit processing unit 100 is the same as the processing of the limit processing unit 86 of the gain adjustment unit 78 described above.
In this case, as indicated by reference numerals in parentheses in FIG. Specifically, in the limit processing unit 100, it is assumed that the moving speeds Vw_x and Vw_y of the virtual wheels 62_x and 62_y respectively match the Vb_x_t and Vb_y_t, respectively. ωw_y_t is calculated by the processing units 86a_x and 86a_y, respectively. Then, the set of rotational angular velocities ωw_x_t and ωw_y_t is converted into a set of rotational angular velocities ω_R_t and ω_L_t of the electric motors 31R and 31L by the XY-RL conversion unit 86b.
Further, these rotational angular velocities ω_R_t and ω_L_t are limited by the limiters 86c_R and 86c_L to values within the allowable range for the right motor and values within the allowable range for the left motor, respectively. Then, the values ω_R_lim2 and ω_L_lim2 after the restriction process are converted into the rotational angular velocities ωw_x_lim2 and ωw_y_lim2 of the virtual wheels 62_x and 62_y by the RL-XY conversion unit 86d.

Next, the moving speeds Vw_x_lim2 and Vw_y_lim2 of the virtual wheels 62_x and 62_y corresponding to the rotational angular velocities ωw_x_lim2 and ωw_y_lim2 are calculated by the processing units 86e_x and 86e_y, respectively, and the moving speeds Vw_x_lim2 and Vw_y_lim2 are output from the limit processing unit 100. The
By the above processing of the limit processing unit 100, the limit processing unit 100, like the limit processing unit 86, has the rotational angular velocities of the electric motors 31R and 31L corresponding to the set of output values Vw_x_lim2 and Vw_y_lim2 deviate from the allowable range. As an essential requirement, the set of output values Vw_x_lim2 and Vw_y_lim2 is generated so that the output values Vw_x_lim2 and Vw_y_lim2 match Vb_x_t and Vb_y_t as much as possible under the necessary conditions.
Note that the permissible ranges for the right motor and the left motor in the limit processing unit 100 do not have to be the same as the permissible ranges in the limit processing unit 86, and may be set to different permissible ranges.

  Returning to the description of FIG. 13, the center-of-gravity speed limiting unit 76 next calculates the control target center-of-gravity speeds Vb_x_mdfd0 and Vb_y_mdfd0 by executing the processing of the calculation units 102_x and 102_y, respectively. In this case, the calculation unit 102_x calculates a value obtained by subtracting the X-axis direction center-of-gravity velocity steady-state deviation predicted value Vb_x_prd from the output value Vw_x_lim2 of the limit processing unit 100 as the control target center-of-gravity velocity Vb_x_mdfd0. Similarly, the calculation unit 102_y calculates a value obtained by subtracting the Y-axis direction center-of-gravity velocity steady deviation predicted value Vb_y_prd from the output value Vw_y_lim2 of the limit processing unit 100 as the Y-axis direction control center-of-gravity velocity Vb_y_mdfd0.

The control target center-of-gravity velocities Vb_x_mdfd0 and Vb_y_mdfd0 determined as described above are the cases where the output values V_x_lim2 and V_y_lim2 in the limit processing unit 100 are not forcibly limited, that is, the X-axis direction of the wheel body 5 Even if the electric motors 31R and 31L are operated so that the respective moving speeds in the Y-axis direction coincide with the output value Vb_x_t of the calculation unit 98_x and the output value Vb_y_t of the calculation unit 98_y, respectively. When the respective rotation angular velocities fall within the allowable range, the required center-of-gravity speeds Vb_x_aim and Vb_y_aim are determined as control target center-of-gravity speeds Vb_x_mdfd0 and Vb_y_mdfd0 as they are, respectively.
In this case, if the required center-of-gravity speed Vb_x_aim in the X-axis direction is “0”, the control target center-of-gravity speed Vb_x_mdfd0 is also “0”, and the required center-of-gravity speed Vb_y_aim in the Y-axis direction is “0”. If there is, the control target center-of-gravity velocity Vb_y_mdfd0 in the Y-axis direction is also “0”.

  On the other hand, when the output values Vw_x_lim2 and Vw_y_lim2 of the limit processing unit 100 are generated by forcibly limiting the input values Vb_x_t and Vb_y_t, that is, the X axis direction and the Y axis direction of the wheel body 5 respectively. When the electric motors 31R and 31L are operated so that the moving speeds coincide with the output value Vb_x_t of the calculation unit 98_x and the output value Vb_y_t of the calculation unit 98_y, the rotational angular speed of either of the electric motors 31R and 31L is allowed. When the value deviates from the range (when the absolute value of one of the rotational angular velocities becomes too high), the correction amount (= Vw_x_lim2) from the input value Vb_x_t of the output value Vw_x_lim2 of the limit processing unit 100 in the X-axis direction. -Vb_x_t), a value obtained by correcting the required center-of-gravity velocity Vb_x_aim (a value obtained by adding the correction amount to Vb_x_aim) is determined as the control center-of-gravity velocity Vb_x_mdfd0 in the X-axis direction. That.

For the Y-axis direction, a value obtained by correcting the requested center-of-gravity velocity Vb_y_aim by the correction amount (= Vw_y_lim2-Vb_y_t) from the input value Vb_y_t of the output value Vw_y_lim2 of the limit processing unit 100 (the correction amount is added to Vb_y_aim) Is determined as the control target center-of-gravity velocity Vb_y_mdfd0 in the Y-axis direction.
In this case, for example, when the required center of gravity speed Vb_x_aim is not “0” regarding the speed in the X-axis direction, the control target center of gravity speed Vb_x_mdfd0 is closer to “0” than the required center of gravity speed Vb_x_aim or The speed is opposite to the speed Vb_x_aim. When the requested center-of-gravity speed Vb_x_aim is “0”, the control target center-of-gravity speed Vb_x_mdfd0 is a speed opposite to the X-axis center of gravity speed steady deviation predicted value Vb_x_prd output by the steady deviation calculator 94_x. . The same applies to the velocity in the Y-axis direction.
The above is the process of the gravity center speed limiting unit 76.

Returning to the description of FIG. 10, the control unit 50 executes the processes of the center-of-gravity speed calculation unit 72, the center-of-gravity speed limit unit 76, the gain adjustment unit 78, and the deviation calculation unit 70 as described above, and then performs posture control. The processing of the calculation unit 80 is executed.
The processing of the attitude control calculation unit 80 will be described below with reference to FIG. In FIG. 14, reference numerals without parentheses are reference numerals related to processing for determining the virtual wheel rotation angular velocity command ωw_x_com that is a target value of the rotation angular velocity of the virtual wheel 62_x rotating in the X-axis direction. The reference numerals with parentheses are reference numerals related to the process of determining the virtual wheel rotational angular velocity command ωw_y_com that is the target value of the rotational angular velocity of the virtual wheel 62_y that rotates in the Y-axis direction.

The posture control calculation unit 80 includes the base body tilt angle deviation measurement value θbe_xy_s calculated by the deviation calculation unit 70, the base body tilt angular velocity measurement value θbdot_xy_s calculated in step S2, and the center of gravity calculated by the center of gravity speed calculation unit 72. The estimated speed value Vb_xy_s and the gain adjustment parameter Kr_xy calculated by the gain adjustment unit 78 are input. Further, the posture control calculation unit 80 includes the target center of gravity speed Vb_xy_mdmf obtained by correcting the control target center of gravity speed Vb_xy_mdfd0 calculated by the center of gravity speed limiting unit 76 using the control target center of gravity speed correction value Vb_y_cancel_cmd calculated by the slider control unit 75. Is entered.
Here, the corrected target center-of-gravity speed Vb_xy_mdmf is calculated by the addition calculation unit 77 and the control target center-of-gravity speed Vb_y_cancel_cmd calculated by the center-of-gravity speed limiting unit 76 and the control target center-of-gravity speed correction value Vb_y_cancel_cmd calculated by the slider control unit 75. Is a value calculated by adding.

The attitude control calculation unit 80 first calculates a virtual wheel rotation angular acceleration command ωdotw_xy_com by using the following expressions 07x and 07y using these input values.

ωwdot_x_cmd = K1_x ・ θbe_x_s + K2_x ・ θbdot_x_s
+ K3_x ・ (Vb_x_s−Vb_x_mdfd) ...... Formula 07x
ωwdot_y_cmd = K1_y ・ θbe_y_s + K2_y ・ θbdot_y_s
+ K3_y · (Vb_y_s−Vb_y_mdfd) ...... Formula 07y

Therefore, in the present embodiment, as an operation amount (control input) for controlling the motion of the mass point 60_x of the inverted pendulum model viewed from the Y-axis direction (and hence the motion of the vehicle system center-of-gravity point viewed from the Y-axis direction). Virtual wheel rotation angular acceleration command ωdotw_x_com and the operation amount (control input) for controlling the motion of the mass point 60_y of the inverted pendulum model viewed from the X-axis direction (and hence the motion of the center of gravity of the vehicle system viewed from the X-axis direction) The virtual wheel rotation angular acceleration command ωdotw_y_com is determined by adding three manipulated variable components (three terms on the right side of equations 07x and 07y).

In this case, the gain coefficients K1_x, K2_x, K3_x related to each manipulated variable component in Expression 07x are variably set according to the gain adjustment parameter Kr_x, and the gain coefficients K1_y, K2_y, K3_y related to each manipulated variable component in Expression 07y are set. Is variably set according to the gain adjustment parameter Kr_y. Hereinafter, the gain coefficients K1_x, K2_x, and K3_x in Expression 07x may be referred to as a first gain coefficient K1_x, a second gain coefficient K2_x, and a third gain coefficient K3_x, respectively. The same applies to the gain coefficients K1_y, K2_y, and K3_y in Expression 07y.
The i-th gain coefficient Ki_x (i = 1, 2, 3) in the expression 07x and the i-th gain coefficient Ki_y (i = 1, 2, 3) in the expression 07y are as follows. It is determined according to the gain adjustment parameters Kr_x and Kr_y by the equations 09x and 09y.

Ki_x = (1−Kr_x) · Ki_a_x + Kr_x · Ki_b_x ...... Expression 09x
Ki_y = (1−Kr_y) · Ki_a_y + Kr_y · Ki_b_y ...... Equation 09y
(I = 1, 2, 3)

Here, Ki_a_x and Ki_b_x in Expression 09x are preliminarily set as the gain coefficient value on the minimum side (side closer to “0”) and the gain coefficient value on the maximum side (side away from “0”), respectively, of the i-th gain coefficient Ki_x. It is a set constant value. The same applies to Ki_a_y and Ki_b_y in Expression 09y.

Accordingly, each i-th gain coefficient Ki_x (i = 1, 2, 3) used in the calculation of Expression 07x is determined as a weighted average value of the corresponding constant values Ki_a_x and Ki_b_x. In this case, the weights applied to Ki_a_x and Ki_b_x are changed according to the gain adjustment parameter Kr_x. Therefore, when Kr_x = 0, Ki_x = Ki_a_x, and when Kr_x = 1, Ki_x = Ki_b_x. As Kr_x approaches “1” from “0”, the i-th gain coefficient Ki_x approaches Ki_b_x from Ki_a_x.
Similarly, each i-th gain coefficient Ki_y (i = 1, 2, 3) used for the calculation of Expression 07y is determined as a weighted average value of the corresponding constant values Ki_a_y and Ki_b_y. In this case, the weights applied to Ki_a_y and Ki_b_y are changed according to the gain adjustment parameter Kr_y. Therefore, as in the case of Ki_x, as the value of Kr_y changes between “0” and “1”, the value of the i-th gain coefficient Ki_y changes between Ki_a_y and Ki_b_y.

Supplementally, the constant values Ki_a_x, Ki_b_x and Ki_a_y, Ki_b_y (i = 1, 2, 3) are included in the constant parameters whose values are set in step S6 or 8.
The attitude control calculation unit 80 calculates the expression 07x using the first to third gain coefficients K1_x, K2_x, and K3_x determined as described above, and thereby the virtual wheel related to the virtual wheel 62_x that rotates in the X-axis direction. Rotational angular acceleration command ωwdot_x_cmd is calculated.
In more detail, with reference to FIG. 14, the posture control calculation unit 80 adds the manipulated variable component u1_x obtained by multiplying the base body tilt angle deviation measured value θbe_x_s by the first gain coefficient K1_x and the base body tilt angular velocity measured value θbdot_x_s. The operation amount components u2_x obtained by multiplying the two gain coefficients K2_x are calculated by the processing units 80a and 80b, respectively. Further, the attitude control calculation unit 80 calculates a deviation (= Vb_x_s−Vb_x_mdfd) between the estimated center-of-gravity velocity value Vb_x_s and the target gravity center velocity for control Vb_x_mdfd (= Vb_x_s−Vb_x_mdfd), and multiplies this deviation by the third gain coefficient K3_x. The manipulated variable component u3_x is calculated by the processing unit 80c. Then, the attitude control calculation unit 80 calculates the virtual wheel rotation angular acceleration command ωwdot_x_com by adding these manipulated variable components u1_x, u2_x, u3_x in the calculation unit 80e.

Similarly, the posture control calculation unit 80 calculates the expression 07y using the first to third gain coefficients K1_y, K2_y, and K3_y determined as described above, so that the virtual wheel 62_y that rotates in the Y-axis direction is obtained. The related virtual wheel rotation angular acceleration command ωwdot_y_cmd is calculated.
In this case, the posture control calculation unit 80 multiplies the operation amount component u1_y obtained by multiplying the base body tilt angle deviation measurement value θbe_y_s by the first gain coefficient K1_y and the base body tilt angular velocity measurement value θbdot_y_s by the second gain coefficient K2_y. The operation amount component u2_y is calculated by the processing units 80a and 80b, respectively. Further, the attitude control calculation unit 80 calculates a deviation (= Vb_y_s−Vb_y_mdfd) between the center-of-gravity velocity estimated value Vb_y_s and the control target center-of-gravity velocity Vb_y_mdfd by the calculation unit 80d, and multiplies this deviation by the third gain coefficient K3_y. The manipulated variable component u3_y is calculated by the processing unit 80c. Then, the posture control calculation unit 80 calculates the virtual wheel rotation angular acceleration command ωwdot_y_com by adding these manipulated variable components u1_y, u2_y, u3_y in the calculation unit 80e.

Here, the first term (= first manipulated variable component u1_x) and the second term (= second manipulated variable component u2_x) on the right side of the expression 07x are the measured values of the base body tilt angle deviation θbe_x_s in the direction around the Y axis. It has a meaning as a feedback manipulated variable component for converging to “0” (converging the base body tilt angle measurement value θb_x_s to the target value θb_x_obj) by the PD law (proportional / differential law) as a feedback control law.
The third term (= third manipulated variable component u3_x) on the right side of Expression 07x converges the deviation between the center of gravity speed estimated value Vb_x_s and the target center of gravity speed Vb_x_mdfd to “0” by a proportional law as a feedback control law ( It has a meaning as a feedback manipulated variable component for converging Vb_x_s to Vb_x_mdfd). The same applies to the first to third terms (first to third manipulated variable components u1_y, u2_y, u3_y) on the right side of Expression 07y.
After calculating the virtual wheel rotation angular acceleration commands ωwdot_x_com and ωwdot_y_com as described above, the attitude control calculation unit 80 then integrates the ωwdot_x_com and ωwdot_y_com by the integrator 80f, thereby obtaining the virtual wheel rotation speed command. ωw_x_com and ωw_y_com are determined.
The above is the details of the processing of the attitude control calculation unit 80.

Supplementally, the third term on the right side of the expression 07x is hypothesized by an expression that is separated into an operation amount component (= K3_x · Vb_x_s) according to Vb_x_s and an operation amount component (= −K3_x · Vb_x_mdfd) according to Vb_x_mdfd. The wheel rotation angular acceleration command ωdotw_x_com may be calculated. Similarly, the third term on the right side of Expression 07y is divided into an operation amount component (= K3_y · Vb_y_s) according to Vb_y_s and an operation amount component (= −K3_y · Vb_y_mdfd) according to Vb_y_mdfd, The wheel rotation angular acceleration command ωdotw_y_com may be calculated.
In the present embodiment, the rotational angular acceleration commands ωw_x_cmd and ωw_y_cmd of the virtual wheels 62_x and 62_y are used as the operation amount (control input) for controlling the behavior of the vehicle system center-of-gravity point. 62_x, 62_y, or a translational force obtained by multiplying the driving torque by the radii Rw_x, Rw_y of the virtual wheels 62_x, 62_y (that is, frictional forces between the virtual wheels 62_x, 62_y and the floor surface). You may make it use as.

Returning to the description of FIG. 10, the control unit 50 next inputs the virtual wheel rotational speed commands ωw_x_com and ωw_y_com determined by the attitude control calculation unit 80 as described above to the motor command calculation unit 82, and the motor command calculation unit By executing the process 82, the speed command ω_R_com of the electric motor 31R and the speed command ω_L_com of the electric motor 31L are determined. The processing of the motor command calculation unit 82 is the same as the processing of the XY-RL conversion unit 86b of the limit processing unit 86 (see FIG. 12).
Specifically, the motor command calculation unit 82 replaces ωw_x, ωw_y, ω_R, and ω_L in the equations 01a and 01b with ωw_x_com, ωw_y_com, ω_R_cmd, and ω_L_cmd, respectively, and sets ω_R_cmd and ω_L_cmd as unknowns. By solving, the speed commands ω_R_com and ω_L_com of the electric motors 31R and 31L are determined.
Thus, the vehicle control calculation process in step S9 is completed.

  As described above, when the control unit 50 executes the control calculation process, the attitude of the base 2 is basically determined to be the measured value of the base body tilt angle deviation θbe_x_s in both the riding mode and the independent mode. , Θbe_y_s so as to maintain a posture where both are “0” (hereinafter, this posture is referred to as a basic posture), in other words, the vehicle system center-of-gravity point (vehicle / occupant overall center of gravity point or vehicle individual center-of-gravity point) The virtual wheel rotation angular acceleration command ωdotw_xy_com as the operation amount (control input) is determined so that the position is maintained almost directly above the straight line connecting the ground contact surfaces of the wheel body 5F and the wheel body 5R. The More specifically, the virtual wheel rotation is performed so that the center-of-gravity speed estimated value Vb_xy_s as the estimated value of the moving speed of the vehicle system center-of-gravity point converges to the control target center-of-gravity speed Vb_xy_mdfd while maintaining the attitude of the base body 2 in the basic attitude. An angular acceleration command ωdotw_xy_com is determined. Note that the control target center-of-gravity velocity Vb_xy_mdfd is normally “0” (specifically, unless the passenger or the like gives additional propulsive force of the vehicle 1 in the boarding mode). In this case, the virtual wheel rotation angular acceleration command ωdotw_xy_com is determined so that the center of gravity of the vehicle system is substantially stationary while maintaining the posture of the base body 2 in the basic posture.

Then, the respective rotational angular velocities of the electric motors 31R and 31L obtained by converting the virtual wheel rotational angular velocity command ωw_xy_com obtained by integrating the components of ωdotw_xy_com are determined as the speed commands ω_R_cmd and ω_L_cmd of the electric motors 31R and 31L. Furthermore, the rotational speeds of the electric motors 31R and 31L are controlled in accordance with the speed commands ω_R_cmd and ω_L_cmd. As a result, the moving speeds of the wheel body 5F and the wheel body 5R in the X-axis direction and the Y-axis direction respectively match the moving speed of the virtual wheel 62_x corresponding to ωw_x_com and the moving speed of the virtual wheel 62_y corresponding to ωw_y_com. To be controlled.
For this reason, for example, when the actual base body tilt angle θb_x shifts forward from the target value θb_x_obj in the direction around the Y axis, the wheel body 5F and the wheel body 5F are used to eliminate the shift (to converge θbe_x_s to “0”). The wheel body 5R moves forward. Similarly, when the actual θb_x shifts backward from the target value θb_x_obj, the wheel body 5F and the wheel body 5R move rearward in order to eliminate the shift (to converge θbe_x_s to “0”).

Further, for example, when the actual base body tilt angle θb_y shifts to the right tilt side from the target value θb_y_obj in the direction around the X axis, the wheel body 5F and the wheel are removed in order to eliminate the shift (to converge θbe_y_s to “0”). The body 5R moves to the right. Similarly, when the actual θb_y shifts to the left side from the target value θb_y_obj, the wheel body 5F and the wheel body 5R move to the left in order to eliminate the shift (to converge θbe_y_s to “0”).
Further, when both the actual base body tilt angles θb_x and θb_y deviate from the target values θb_x_obj and θb_y_obj, respectively, the moving operation of the wheel body 5F and the wheel body 5R in the front-rear direction and the deviation of θb_y to eliminate the deviation of θb_x. The wheel body 5F and the wheel body 5R are moved in the left-right direction to eliminate the problem, and the wheel body 5F and the wheel body 5R It moves in a direction inclined with respect to both directions.

Thus, when the base body 2 is tilted from the basic posture, the wheel body 5F and the wheel body 5R move toward the tilted side. Therefore, for example, in the boarding mode, when the occupant intentionally tilts the upper body, the wheel body 5F and the wheel body 5R move to the tilted side.
When the control target center-of-gravity speeds Vb_x_mdfd and Vb_y_mdfd are “0”, when the posture of the base body 2 converges to the basic posture, the movement of the wheel body 5F and the wheel body 5R almost stops. Further, for example, when the inclination angle θb_x in the direction around the Y axis of the base body 2 is maintained at a constant angle inclined from the basic posture, the moving speeds in the X axis direction of the wheel bodies 5F and 5R are constant corresponding to the angles. (The moving speed having a constant steady-state deviation with the control target center-of-gravity speed Vb_x_mdfd). The same applies to the case where the inclination angle θb_y of the base 2 in the direction around the X axis is maintained at a constant angle inclined from the basic posture.

By the way, the vehicle system center-of-gravity point is located on a straight line connecting the ground contact points of the wheel body 5F and the wheel body 5R, or inside the polygon that connects the center positions of the moving operation parts of each of the plurality of wheels. In the state where the center of gravity is located (reference state), the base body 2 is not tilted without moving the wheel body 5F and the wheel body 5R. Therefore, the wheel body 5F and the wheel pair 5R are stopped in the reference state. Is desirable. In many cases, the target value θb_xy_obj of the base body tilt angle θb_xy basically deviates from the target value θb_xy_obj in the base body tilt angle θb_xy in the reference state.
In such a case, the wheel is caused by a deviation between the base body tilt angle θb_xy_s and the target value θb_xy_obj of the base body tilt angle θb_xy (the passenger is unconsciously tilted with the seat portion 12 and the base body 2). The body 5F and the wheel body 5R move.

Therefore, in this embodiment, the slider control unit 75 calculates the slider drive command S_cmd and drives the actuator 422 so that the electric vehicle (the reception position of the electric vehicle) does not move, and the wheel body 5F and the wheel body 5R are based on the base body. The base 2 is kept horizontal by being moved relative to the base 2.
That is, the slider control unit 75 drives the actuator 422 based on the center of gravity speed estimated value Vb_xy_s to move the wheel body 5F and the wheel body 5R, and calculates the control target center of gravity speed correction value Vb_y_cancel_cmd. The control target center-of-gravity speed Vb_xy_mdfd0 calculated by the speed limiter 76 is corrected. The attitude control calculation unit 80 determines a virtual wheel rotation angular velocity command ωw_xy_cmd based on the corrected control target center-of-gravity velocity Vb_xy_mdfd.
Specifically, the control unit 50 updates the slider drive command S_cmd by sequentially executing the processing shown in the flowchart of FIG. 15 at a predetermined control processing cycle, and the control calculated together with the updated slider drive command S_cmd. The virtual wheel rotation angular velocity command ωw_xy_cmd is determined using the target center-of-gravity velocity correction value Vb_y_cancel_cmd.

In the following, the control unit 50 first determines in step S21 whether an update condition for updating the slider drive command S_cmd is satisfied, and a switching signal corresponding to the determination is input to the slider operation switching unit 752. The
Various specific conditions are conceivable. For example, a button type provided at a predetermined position of the base 2 and the seat portion 12 so as to allow an operation in a state where an occupant is on the electric vehicle 1. When the switch output is ON, or when the load measurement value indicated by the output of the weight sensor 54 indicates that the occupant has boarded, within a certain time (from the time of boarding until the timer expires) It is within time). At this time, the slider operation switching unit 752 is in a mode for performing a slider operation.

When the update condition is satisfied, the control unit 50 executes the first mode calculation process of step S22, and when there is no trigger input for updating the slider drive command S_cmd, the second mode of step S23. The calculation process is executed.
Here, the first mode in the present embodiment is a calculation process for determining the virtual wheel rotation angular velocity command ωw_xy_cmd while updating the slider drive command S_cmd, and the second mode is a position moved by relative movement in the first mode. Is a calculation process for determining a virtual wheel rotation angular velocity command ωw_xy_cmd for driving the wheel body 5F and the wheel pair 5R.
In any of the calculation processes in the first mode and the second mode, the attitude control calculation unit 80 of the control unit 50 determines the virtual wheel rotation angular velocity command ωw_xy_cmd as described above, and uses the determined virtual wheel rotation angular velocity command ωw_xy_cmd as the motor. A series of processes that are input to the command calculation unit 82 and executed by the motor command calculation unit 82 are continued.

First, the calculation in the first mode in step S22 will be described.
In the calculation process of the first mode, the attitude control calculation unit 80 uses the control target center-of-gravity velocity correction value Vb_y_cancel_cmd calculated by the slider control unit 75 in the process of determining the virtual wheel rotation angular acceleration command ωwdot_xy_cmd using the previous expressions 07x and 07y. The corrected target center-of-gravity velocity Vb_xy_mdmf is used. The initial value of the slider drive command S_cmd is set to “0”.
In the control unit 50, the slider control unit 75 calculates the slider control command S_cmd so that the estimated center-of-gravity velocity value Vb_y_s is closer to “0”. Further, the slider control unit 75 calculates a control target center-of-gravity speed correction value Vb_y_cancel_cmd for a shift caused by relative movement of the wheel body 5F and the wheel body 5R, and corrects the control target center-of-gravity speed Vb_y_mdmf.

In this way, in the control system that feeds back the integrated value of the center-of-gravity speed estimated value Vb_xy_s (Vb_x_s, Vb_y_s), the steady-state deviation can be suppressed by determining the slider control command S_cmd, and the center-of-gravity speed estimated value Vb_xy_s (Vb_x_s , Vb_y_s) can be converged to zero. Thereby, while the movement of the electric vehicle 1 can be suppressed and stopped, the occupant positions the vehicle system center-of-gravity point in a straight line connecting the ground point of the wheel body 5F and the wheel body 5R with the electric vehicle stopped. And the level of the vehicle (that is, θb_xy_obj is almost “0”) can be maintained in a stopped state.
The calculation process in the first mode is continuously executed as long as the determination in step S21 is “YES”. That is, it is continuously executed as long as the update condition for updating the slider control command S_cmd is satisfied, and the calculation process in the first mode is terminated when the update condition is not satisfied. Therefore, when the output of the button-type switch provided at a predetermined position of the base body 2 or the seat portion 12 is an update condition, as long as the switch continues to be pressed by an occupant on the electric vehicle 1, the calculation in the first mode is performed. The processing is executed, and the calculation process in the first mode is completed at the timing when the occupant releases the switch (the center of gravity speed estimated value Vb_xy_s converges to 0 and the electric vehicle 1 stops).

In addition, in the case where the update condition is that the measured value of the load indicated by the output of the load sensor 54 indicates that the occupant is on board within a certain period of time, within a predetermined time from when the boarding is started until the timer expires. The first mode calculation process is executed, and the first mode calculation process is terminated when the timer expires.
It should be noted that the end condition of the calculation process in the first mode may be set separately from the update condition. For example, as a result of the calculation process in the first mode, the center-of-gravity velocity estimated value Vb_xy_s of the electric vehicle 1 may be in a state equal to “0” or almost “0” as an end condition of the calculation process in the first mode.

  Next, in the calculation process of the second mode in step S23, the attitude control calculation unit 80 calculates the virtual wheel rotation angle according to the previous expressions 07x and 07y based on the positions of the wheel body 5F and the wheel body 5R relatively moved in step S22. The acceleration command ωwdot_xy_cmd is determined. At this time, the slider operation switching unit 752 selects a mode in which the slider operation is not performed according to the switching signal, does not operate the slider mechanism, and the control target center-of-gravity velocity correction value Vb_y_cancel_cmd output by the slider control unit 75. Is “0”.

The above is the arithmetic processing in the first mode in step S22 and the second mode in step S23 in the present embodiment.
In the present embodiment, there is no required center-of-gravity speed Vb_xy_aim as a required value of the center-of-gravity speed Vb_xy estimated to be required by a steering operation of the electric vehicle 1 by an occupant or the like (an operation for adding a propulsive force to the electric vehicle). In this case, that is, the case where the required center-of-gravity speed Vb_xy_aim is “0” has been described. It is also possible to provide a determination block for determining and perform the calculation processing in the first mode and the second mode only when the required center-of-gravity speed Vb_xy_aim is not present (when the required center-of-gravity speed Vb_xy_aim is “0”). Good.
In addition, when the requested center-of-gravity speed Vb_xy_aim is detected in the state in which the calculation process in the first mode has already been performed, the calculation process in the first mode is terminated, and the wheel body 5F updated in the first mode. The second mode calculation process may be executed based on the position of the wheel body 5R after the relative movement.

  Further, for example, in a situation where both the required center of gravity speeds Vb_x_aim and Vb_y_aim generated by the required center of gravity speed generation unit 74 are “0”, the amount of inclination of the base body 2 from the basic posture (base body tilt angle deviation measurement) The value θbe_x_s, θbe_y_s) is relatively large, and the moving speed of one or both of the wheel body 5F and the wheel body 5R in the X-axis direction and the Y-axis direction necessary for eliminating or maintaining the inclination amount ( These movement velocities correspond to the center of gravity speed steady deviation predicted values Vb_x_prd and Vb_y_prd shown in FIG. 13, respectively, so that the rotational angular velocities of one or both of the electric motors 31R and 31L deviate from the allowable range. In a situation where the movement speed is excessive, the speeds opposite to the movement speed of the wheel body 5F and the wheel body 5R (specifically, Vw_x_lim2-Vb_x_prd and Vw_y_lim2-Vb_y _prd) is determined as the control target center-of-gravity speeds Vb_x_mdfd and Vb_y_mdfd. Then, the operation amount components u3_x and u3_y among the operation amount components constituting the control input are determined so as to converge the center-of-gravity speed estimated values Vb_x_s and Vb_y_s to the control target center-of-gravity speeds Vb_x_mdfd and Vb_y_mdfd, respectively. For this reason, it is possible to prevent the amount of inclination of the base body 2 from the basic posture from becoming excessive, and consequently, the rotational angular velocity of one or both of the electric motors 31R and 31L is prevented from becoming too high.

Further, in the gain adjusting unit 78, one or both of the center-of-gravity velocity estimated values Vb_x_s and Vb_y_s are increased, and as a result, it is necessary for eliminating the inclination of the base body 2 from the basic posture or maintaining the inclination amount. Excessive movement in which the moving speed of one or both of the wheel body 5F and the wheel body 5R in the X-axis direction and the Y-axis direction causes the rotational angular speed of one or both of the electric motors 31R and 31L to deviate from the allowable range. In a situation where there is a risk of speed, as the deviation becomes more prominent (specifically, as the absolute values of Vover_x and Vover_y shown in FIG. 11 increase), one or both of the gain adjustment parameters Kr_x and Kr_y is from “0”. It can be brought close to “1”.
In this case, each i-th gain coefficient Ki_x (i = 1, 2, 3) calculated by Expression 09x is changed from the minimum constant value Ki_a_x to the maximum constant value Ki_b_x as Kr_x approaches “1”. Get closer. The same applies to each i-th gain coefficient Ki_y (i = 1, 2, 3) calculated by the expression 09y.

As the absolute value of the gain coefficient increases, the sensitivity of the operation amount (virtual wheel rotation angular acceleration commands ωdotw_x_cmd, ωdotw_y_cmd) with respect to the change in the inclination of the base body 2 increases. Therefore, when the inclination amount of the base body 2 from the basic posture is increased, the moving speeds of the wheel body 5F and the wheel body 5R are controlled so as to be quickly eliminated. Accordingly, it is strongly suppressed that the base body 2 is greatly inclined from the basic posture, and as a result, the moving speed of one or both of the wheel body 5F and the wheel body 5R in the X-axis direction and the Y-axis direction is one of the electric motors 31R and 31L. Alternatively, it is possible to prevent an excessive movement speed that would cause both rotational angular velocities to deviate from the allowable range.
Further, in the boarding mode, the requested center-of-gravity speed generation unit 74 generates the requested center-of-gravity speed Vb_x_aim, Vb_y_aim (the requested center-of-gravity speed where one or both of Vb_x_aim, Vb_y_aim are not “0”) in response to a request by a steering operation by an occupant or the like. In this case, unless one or both of the electric motors 31R and 31L has a high rotational angular velocity that deviates from the allowable range (specifically, as long as Vw_x_lim2 and Vw_y_lim2 shown in FIG. 12 match Vb_x_t and Vb_y_t, respectively). ), The required center-of-gravity speeds Vb_x_aim and Vb_y_aim are determined as the control target center-of-gravity speeds Vb_x_mdfd and Vb_y_mdfd, respectively. Therefore, the moving speeds of the wheel body 5F and the wheel body 5R are controlled so as to realize the required center of gravity speeds Vb_x_aim and Vb_y_aim (so that the actual center of gravity speed approaches the required center of gravity speeds Vb_x_aim and Vb_y_aim).

  The slider control unit 75 calculates a slider command value indicating the amount and direction of movement of the wheel 3 (4) moving in the left-right direction by the slider mechanism, in accordance with the center-of-gravity speed estimated value Vb_xy_s calculated by the center-of-gravity speed calculating unit 72. Further, the slider control unit 75 corrects the control target center-of-gravity speed Vb_xy_mdmf by the control target center-of-gravity speed correction value Vb_y_cancel_cmd based on the calculated slider command value, and determines the movement amount and direction of the wheel 3 (4) by the slider mechanism. The configuration is such that the body 5F (5R) is fed back in the amount and direction of movement in the left-right direction. Thus, by driving the wheel body 5F (5R) in the same amount and direction of movement (relative movement) in the left and right direction by the slider mechanism, the wheel body 5F (5R) and the floor are moved by the relative movement by the slider mechanism. Friction generated between the surface and the surface can be reduced, and the orientation of the substrate 2 can be prevented from changing.

Here, the correspondence between the present embodiment and the present invention will be supplemented.
In the present embodiment, the front-rear direction (X-axis direction) and the left-right direction (Y-axis direction) of the passenger boarding the vehicle 1 correspond to the first direction and the second direction in the present invention, respectively.
The required center-of-gravity speed generation unit 74 implements a target speed determination means in the present invention. In this case, in this embodiment, the vehicle system center-of-gravity point (more precisely, the vehicle / occupant overall center-of-gravity point) corresponds to a predetermined representative point of the vehicle in the present invention, and the vehicle system center-of-gravity point velocity vector ↑ Vb The required center-of-gravity velocity vector ↑ Vb_aim, which is a target value, corresponds to the target velocity vector in the present invention.
Further, the center-of-gravity speed limiting unit 76, the attitude control calculation unit 80, and the motor command calculation unit 82 implement the moving operation unit control means in the present invention.

Next, some modifications relating to the embodiment described above will be described.
In the above embodiment, the front wheel 3 and the rear wheel 4 are described as being omnidirectional driving wheels shown in FIGS. 3 to 6, but either the front wheel 3 or the rear wheel 4 is an omnidirectional driving wheel. May be.
In the above-described embodiment, the case where both the front wheel 3 and the rear wheel 4 are movable relative to the base body in the left-right direction (Y direction) by the slider mechanism has been described. Only one of them may be relatively movable. For example, as shown in FIG. 16, only the front wheel 4 may be relatively movable in the left-right direction by the slider mechanism. Also in this case, as shown in FIG. 16 (b), by moving the front wheel 3 relative to each other as in the embodiment, the center positions of the moving operation portions (5F, 5R) respectively included in the front wheel 3 and the rear wheel 4 are obtained. The barycentric point G is positioned immediately above the connecting straight line.

  Moreover, although the said embodiment demonstrated the case where the two wheels of the front wheel 3 and the rear wheel 4 were provided, as shown in FIG. 17, an electric vehicle provided with three wheels may be sufficient. For example, the electric vehicle is connected to the base 2, the front wheel 3 attached to the base 2, the front wheel 3 having a slider mechanism that can move relative to the base, the shaft 231, and both ends of the shaft 231. A right rear wheel 232 and a left rear wheel 233, and a joint 234 that is provided between the shaft 231 and the base 2 and is rotatable in the torsion direction. In this case, as shown in FIG. 17B, the slider control unit 75 and the slider command calculation unit 85 have the center of gravity G within the triangle connecting the center points of the front wheel 3, the right rear wheel 232, and the left rear wheel 234. The front wheel 3 is relatively moved so that is positioned.

  Moreover, in the said embodiment, you may use the mechanism shown in FIG. 18 as a mechanism which moves two wheels, the front wheel 3 and the rear wheel 4, in the left-right direction. As shown in FIG. 18, the left arm support 241 and the right arm support 242 provided on the base 2, the right actuator 243 built in the right arm support 241, and the left built in the left arm support 242. Actuator 244, right arm 245 having one end connected to rotating shaft 243a of right actuator 243, left arm 246 having one end connected to rotating shaft 244a of left actuator 244, and one end Is supported at the other end of the right arm 245 so as to be swingable, and the other end is supported at the other end of the left arm 246 so as to be swingable. The wheel support 247 has a cover member. A slider mechanism having a wheel 3 (4) to which 21 is fixed may be used. In this case, the slider command calculation unit 85 outputs a drive command to each of the right actuator 243 and the left actuator 244 to move the wheel 3 (4) in the left-right direction.

  In addition, the slider operation switching unit 752 switches the mode according to a switching signal input from the outside. However, the present invention is not limited to this, and for example, a weight sensor that detects a change in weight on the step floor 9 or the loading platform 17. And a slider operation may be performed when a change in weight is detected by a weight sensor.

Moreover, in each said embodiment, although the vehicle 1 of the structure shown in FIG.1 and FIG.2 was illustrated, the omnidirectional vehicle 1 in this invention is not restricted to the vehicle illustrated in this embodiment.
Specifically, the wheel body 5F and the wheel body 5R as the moving operation unit of the vehicle 1 according to the present embodiment have an integral structure. For example, the structure described in FIG. It may be. That is, a plurality of rollers are extrapolated on a rigid annular shaft body so that the shaft centers in the tangential direction of the shaft body, and the plurality of rollers are circumferentially arranged along the shaft body. You may comprise a wheel body by arranging in a direction.
Further, the moving operation unit may have a crawler-like structure as described in FIG.

Alternatively, for example, as described in FIG. 5 of Patent Document 1, FIG. 7 of Patent Document 2, or FIG. 1 of Patent Document 3, the moving operation unit is configured by a sphere, and this sphere is used as an actuator device ( For example, the vehicle may be configured to be rotationally driven in the direction around the X axis and the direction around the Y axis by the actuator device having the wheel body 5F and the wheel body 5R).
Moreover, in this embodiment, although the vehicle 1 provided with the seating part 7 was illustrated as a passenger | crew's boarding part, as shown in FIG. The vehicle may have a structure in which the step of placing the vehicle and the portion gripped by the occupant standing on the step are assembled to the base body.
As described above, the present invention can be applied to omnidirectional vehicles having various structures as seen in Patent Documents 1 to 3 and the like.

1 Electric vehicle (inverted pendulum moving body)
2 Substrate 5F Wheel body (moving motion part)
5R Wheel body (moving motion part)
52 Tilt sensor (Tilt detector)
50 Control unit (control unit)
422 Actuator (relative drive)

Claims (4)

A substrate;
A moving operation unit comprising a plurality of wheels including an omnidirectional moving wheel attached to the base body and capable of being driven in all directions on the floor surface;
A relative drive unit that moves at least one of the plurality of wheels relative to the base body;
An inclination detector for detecting an inclination angle of the base body and a change amount of the inclination angle;
A control unit that outputs a drive command to the relative drive unit according to the tilt angle and the amount of change in the tilt angle, and
When a predetermined condition is satisfied, the control unit moves the position of at least one of the plurality of wheels relative to the base so that the inclination angle of the base approaches a predetermined value. Inverted pendulum type moving body. A substrate;
A moving operation unit comprising a plurality of wheels including an omnidirectional moving wheel attached to the base body and capable of being driven in all directions on the floor surface;
A relative drive unit that moves at least one of the plurality of wheels relative to the base body;
An inclination detector for detecting an inclination angle of the base body and a change amount of the inclination angle;
A control unit that outputs a drive command to the relative drive unit according to the tilt angle and the amount of change in the tilt angle, and
When the tilt detection unit detects the tilt of the base body, the control unit drives the relative drive unit according to the detected tilt to move at least one of the plurality of wheels relative to the base body. The center of gravity is positioned on a straight line that connects the center positions of the moving operation portions of the plurality of wheels, or inside a polygon that connects the center positions of the movement operation portions of the plurality of wheels. An inverted pendulum type moving body characterized in that The inverted pendulum type moving body is:
A weight sensor for detecting a change in weight applied to the substrate;
The inverted pendulum type moving body according to claim 1 or 2, wherein the control unit drives the relative drive unit according to a change in weight by the weight sensor. When the relative drive unit causes the relative drive unit to relatively move at least one omnidirectional moving wheel among the plurality of wheels, the control unit has the same amount and direction as the amount and direction of relative movement of the wheel by the relative drive unit. The inverted pendulum type moving body according to any one of claims 1 to 3, wherein the wheel is driven by the moving operation unit.

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