JP2010047095A - Vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance stability and robust characteristics of driving and attitude control by applying a sliding mode control to driving and attitude control of a vehicle using an attitude control of an inverted pendulum, and setting a sliding plane introducing a driving state and a car body attitude to target states so as to stably and smoothly approach to the target state, and to securely and comfortably drive in various driving conditions. <P>SOLUTION: The vehicle includes: a car body; a drive wheel 12 turnably mounted on the car body; and a vehicle control device for controlling the attitude of the car body by controlling a driving torque given to the drive wheel 12. The vehicle control device determines the target state of the drive wheel or the car body based on the amount of steering operation of a steering device, determines the sliding plane based on the determined target state, and determines the drive torque based on positional relations among an actual state, the target state, and the sliding plane. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  Conventionally, a technique related to a vehicle using posture control of an inverted pendulum has been proposed. For example, a vehicle that has two drive wheels arranged on the same axis and drives by sensing a change in the posture of the vehicle body due to the movement of the center of gravity of the driver, and moves while controlling the posture with a single spherical drive wheel. Technologies for vehicles and the like have been proposed (see, for example, Patent Document 1).

In this case, the balance and operation state of the vehicle body is detected by a sensor, and the vehicle is stopped or moved by controlling the operation of the rotating body.
JP 2004-129435 A

  However, in the conventional vehicle, the vehicle is driven while maintaining the inverted state by performing linear feedback control of the tilt state of the vehicle body and the rotation state of the rotating body. Since driving performance and robustness are low, driving conditions are greatly limited. For example, the vehicle body may tilt more than necessary during acceleration / deceleration. In addition, the movement and the posture of the vehicle body change greatly depending on the weight of the passenger and the load. Furthermore, the vehicle body may be greatly inclined due to disturbances such as resistance caused by road surface unevenness.

  In general, in linear feedback control, the transition path from a certain state to a target state (how to change) cannot be commanded or controlled in detail, so the vehicle body is temporarily tilted greatly, etc. Problems may occur.

  The present invention solves the problems of the conventional vehicle and applies sliding mode control to vehicle traveling and posture control using the posture control of an inverted pendulum, thereby sliding the vehicle state and the vehicle body posture to the target state. By setting the plane and approaching the target state stably and smoothly, the stability and robustness of running and posture control can be further improved, and for various running conditions, safely and It aims at providing the vehicle which can drive | work comfortably.

  Therefore, in the vehicle of the present invention, a vehicle body, a drive wheel rotatably attached to the vehicle body, and a vehicle control device that controls the attitude of the vehicle body by controlling a drive torque applied to the drive wheel. The vehicle control device determines a target state of the driving wheel or the vehicle body based on a steering operation amount of the control device, determines a sliding plane based on the determined target state, and determines the real state and the target state. And the driving torque is determined by the positional relationship between the sliding plane and the sliding plane.

  In another vehicle of the present invention, the sliding plane is a plane that guides a control transition path to the target state, and is set in a space having coordinates of the state quantities of the real state and the target state. It is a hyperplane.

  In still another vehicle of the present invention, the target state is a state in which the rotational angular velocity of the driving wheel becomes a target value, and the sliding plane includes a rotational angular velocity of the driving wheel and an inclination angle of the vehicle body. The space is set with the vehicle body tilt angular velocity as coordinates.

  In still another vehicle of the present invention, the target state is a state in which the inclination angle of the vehicle body becomes a target value, and the sliding plane coordinates the inclination angle of the vehicle body and the inclination angular velocity of the vehicle body. Is set in the space.

  In still another vehicle of the present invention, the target value of the tilt angle of the vehicle body is a reference value determined based on the target value of the rotational angular velocity of the drive wheel and the target value of the rotational angular velocity of the drive wheel. And the correction value determined based on the difference between the actual values, and the correction value is only when the difference between the target value of the rotational angular velocity of the drive wheel and the actual value is larger than a predetermined threshold value. The vehicle body is given an extra tilt in a direction to reduce the difference between the target value and the actual value of the rotational angular velocity of the drive wheels.

  In yet another vehicle of the present invention, the vehicle further includes an active weight portion movably attached to the vehicle body, and the vehicle control device includes the drive torque and the position of the active weight portion. At least one is controlled to control the posture of the vehicle body, and the driving torque and the thrust of the active weight portion are determined according to the positional relationship between the actual state, the target state, and the sliding plane.

  In still another vehicle of the present invention, the target state is a state in which the rotational angular velocity of the driving wheel becomes a target value, and the sliding plane includes a rotational angular velocity of the driving wheel and an inclination angle of the vehicle body. It consists of two planes set in a space having at least two of the inclination angular velocity of the vehicle body, the position of the active weight portion, and the moving speed of the active weight portion as coordinates.

  In yet another vehicle of the present invention, the target state is a state in which the rotational angular velocity of the drive wheel becomes a target value, and the sliding plane includes an inclination angle of the vehicle body and an inclination angular velocity of the vehicle body. A first sliding plane set in a space having coordinates, and a second sliding plane set in a space having coordinates of the rotational angular velocity of the driving wheel, the position of the active weight portion, and the moving speed of the active weight portion. .

  In still another vehicle of the present invention, the target state is a state in which the position of the active weight portion becomes a target value, and the sliding plane includes an inclination angle of the vehicle body and an inclination angular velocity of the vehicle body. The first sliding plane is set in a space having coordinates, and the second sliding plane is set in a space having coordinates of the position of the active weight part and the moving speed of the active weight part.

  In still another vehicle of the present invention, the target value of the position of the active weight portion is a reference value determined based on a target value of the rotational angular velocity of the driving wheel and a target of the rotational angular velocity of the driving wheel. And the correction value determined based on the difference between the actual value and the correction value is only when the difference between the target value of the rotational angular velocity of the drive wheel and the actual value is greater than a predetermined threshold value. The active weight is excessively moved in the direction of reducing the difference between the target value and the actual value of the rotational angular velocity of the drive wheel.

  According to the structure of Claim 1 and 2, high stability and robustness can be acquired, maintaining the simplicity of control, and it can drive | work safely and comfortably also in various driving | running conditions. .

  According to the configuration of the third aspect, it is possible to suppress a change in the vehicle body inclination angle during acceleration / deceleration or a disturbance action, and to realize a substantially constant vehicle operation with respect to a change in the weight of the occupant.

  According to the configuration of the fourth aspect, vibration of the vehicle body can be suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with high accuracy.

  According to the configuration of the fifth aspect, the vehicle body posture can be stably controlled while ensuring the acceleration / deceleration performance of the vehicle.

  According to the configurations of claims 6 and 7, it is possible to suppress changes in the vehicle body inclination angle and the position of the riding portion during acceleration / deceleration and disturbance action, and substantially constant vehicle operation with respect to changes in passenger weight, etc. Can be realized.

  According to the configuration of the eighth aspect, it is possible to further suppress changes in the vehicle body inclination angle during acceleration / deceleration and disturbance.

  According to the configuration of the ninth aspect, the vibration of the vehicle body can be further suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with higher accuracy.

  According to the configuration of the tenth aspect, the vehicle body posture can be controlled more stably while securing the acceleration / deceleration performance of the vehicle.

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

  FIG. 1 is a schematic diagram showing the configuration of a vehicle in a first embodiment of the present invention, and shows a state in which an occupant is moving forward in an accelerated state, and FIG. 2 is a first embodiment of the present invention. 1 is a block diagram showing a configuration of a vehicle control system in FIG.

  In FIG. 1, reference numeral 10 denotes a vehicle according to the present embodiment, which includes a body portion 11, a drive wheel 12, a support portion 13, and a riding portion 14 on which an occupant 15 rides. Can be tilted. Then, the posture of the vehicle body is controlled similarly to the posture control of the inverted pendulum. In the example shown in FIG. 1, the vehicle 10 is accelerating in the direction indicated by the arrow A, and the vehicle body is tilted in the traveling direction.

  The drive wheel 12 is rotatably supported with respect to a support portion 13 that is a part of the vehicle body, and is driven by a drive motor 52 as a drive actuator. The axis of the drive wheel 12 exists in a direction perpendicular to the plane shown in FIG. 1, and the drive wheel 12 rotates around that axis. The drive wheel 12 may be singular or plural, but in the case of plural, the drive wheels 12 are arranged on the same axis in parallel. In the present embodiment, description will be made assuming that there are two drive wheels 12. In this case, each drive wheel 12 is independently driven by an individual drive motor 52. As the drive actuator, for example, a hydraulic motor, an internal combustion engine, or the like can be used, but here, the description will be made assuming that the drive motor 52 that is an electric motor is used.

  The main body 11 that is a part of the vehicle body is supported from below by the support 13 and is positioned above the drive wheels 12. A riding part 14 is attached to the main body part 11. In the present embodiment, for the sake of explanation, an example in which the occupant 15 is on the riding part 14 will be described. However, the occupant 15 does not necessarily have to be on the riding part 14, for example, When the vehicle 10 is operated by remote control, the occupant 15 may not be on the riding section 14, or cargo may be loaded instead of the occupant 15. The riding part 14 is the same as a seat used for automobiles such as passenger cars and buses, and includes a seat surface part 14a, a backrest part 14b, and a headrest 14c.

  An input device 30 including a joystick 31 as a target travel state acquisition device is disposed beside the boarding unit 14. The occupant 15 controls the vehicle 10 by operating a joystick 31 as a control device, that is, inputs a travel command such as acceleration, deceleration, turning, in-situ rotation, stop, and braking of the vehicle 10. ing. If the occupant 15 can operate and input a travel command, other devices such as a pedal, a handle, a jog dial, a touch panel, and a push button can be obtained instead of the joystick 31 to obtain a target travel state. It can also be used as a device.

  In addition, when the vehicle 10 is steered by remote control, it can replace with the said joystick 31, and can use the receiver which receives the driving | running | working command from a controller with a wire communication or a radio | wireless as a target driving | running | working state acquisition apparatus. Further, when the vehicle 10 automatically travels according to predetermined travel command data, a data reader that reads travel command data stored in a storage medium such as a semiconductor memory or a hard disk is used as a target travel instead of the joystick 31. It can be used as a status acquisition device.

  In addition, the vehicle 10 includes a control ECU (Electronic Control Unit) 20 as a vehicle control device, and the control ECU 20 includes a main control ECU 21 and a drive wheel control ECU 22. The control ECU 20, the main control ECU 21, and the drive wheel control ECU 22 include a calculation unit such as a CPU and an MPU, a storage unit such as a magnetic disk and a semiconductor memory, an input / output interface, and the like, and a computer system that controls the operation of each part of the vehicle 10. For example, although it is disposed in the main body 11, it may be disposed in the support portion 13 or the riding portion 14. Further, the main control ECU 21 and the drive wheel control ECU 22 may be configured separately or may be configured integrally.

  The main control ECU 21 functions as a part of the drive wheel control system 50 that controls the operation of the drive wheel 12 together with the drive wheel control ECU 22, the drive wheel sensor 51, and the drive motor 52. The drive wheel sensor 51 includes a resolver, an encoder, and the like, functions as a drive wheel rotation state measuring device, detects a drive wheel rotation angle and / or a drive wheel rotation angular velocity indicating the rotation state of the drive wheel 12, and controls the main control ECU 21. Send to. The main control ECU 21 transmits a drive torque command value to the drive wheel control ECU 22, and the drive wheel control ECU 22 supplies an input voltage corresponding to the received drive torque command value to the drive motor 52. The drive motor 52 applies drive torque to the drive wheels 12 in accordance with the input voltage, thereby functioning as a drive actuator.

  Furthermore, the main control ECU 21 functions as a part of the vehicle body control system 40 that controls the posture of the vehicle body, together with the drive wheel control ECU 22, the vehicle body tilt sensor 41, and the drive motor 52. The vehicle body tilt sensor 41 includes an acceleration sensor, a gyro sensor, and the like, and functions as a vehicle body tilt state measuring device. . Then, the main control ECU 21 transmits a drive torque command value to the drive wheel control ECU 22.

  The main control ECU 21 receives a travel command from the joystick 31 of the input device 30. Then, the main control ECU 21 transmits a drive torque command value to the drive wheel control ECU 22.

  Each sensor may acquire a plurality of state quantities. For example, an acceleration sensor and a gyro sensor may be used together as the vehicle body tilt sensor 41, and the vehicle body tilt angle and the vehicle body tilt angular velocity may be determined from the measured values of both.

  Next, the operation of the vehicle 10 configured as described above will be described. First, an outline of the travel and attitude control process will be described.

  FIG. 3 is a diagram for explaining the difference between the linear feedback control and the sliding mode control, and FIG. 4 is a flowchart showing the operation of the vehicle travel and attitude control processing in the first embodiment of the present invention. FIG. 3A shows linear feedback control, and FIG. 3B shows sliding mode control.

In the case of a conventional vehicle as described in the section of “Background Art”, linear feedback control is performed, so that only a target state is set without setting a transition path to the target state. The state changes as shown.

From the transition path shown in FIG. 3A, it can be seen that in the case of the linear feedback control in the conventional vehicle, the change in the vehicle body inclination angle θ ₁ is very large and the stability is low. In the case of the linear feedback control, since the robustness is low, for example, if the weight of the occupant 15 is greatly different from the assumed value or is subject to disturbance due to road surface unevenness or the like, appropriate control becomes difficult.

  However, running and posture control is performed according to the acceleration of the drive wheels 12, an ideal target route is set according to the set target state, and control is performed so that the transition route changes along the target route. If it does, stability and robustness can be improved. However, the control program becomes complicated and the amount of control processing increases, and the simplicity of control is lost.

  Therefore, the sliding mode control is performed, and as shown in FIG. 3B, the sliding plane that leads to the target state (in the example shown in the figure, it is a hyperplane in the two-dimensional Euclidean space, so it becomes a straight line. And the state is shifted along the target route. Thereby, high stability and robustness can be obtained while maintaining simplicity of control.

  Here, for simplification, “Euclidean space” defined in mathematics is referred to as “space”, and “hyperplane” is referred to as “plane”.

  In the present embodiment, specifically, the sliding plane is set for the drive wheel rotation angular velocity, the vehicle body inclination angle, and the vehicle body inclination angular velocity. Then, a drive torque is applied so as to change the state along the sliding plane. That is, the driving torque is determined based on the actual state of the vehicle 10 as a current state, the target state, and the positional relationship of the sliding plane.

  Thereby, the problem of linear feedback control can be solved. In the case of linear feedback control, the vehicle body may tilt more than necessary during sudden acceleration / deceleration. If the vehicle speed commanded by the occupant 15 is to be realized by feedback control of the driving wheel rotational angular velocity, the inertial force accompanying the acceleration / deceleration of the vehicle 10 and the anti-torque of the driving torque affect the vehicle body posture control. For example, when making a sudden start, the vehicle body is greatly tilted and then accelerated while being raised. That is, an overshoot of the vehicle body tilt angle occurs. In addition, the vehicle body may vibrate greatly due to disturbances such as resistance caused by road surface unevenness. Further, when the weight of the occupant 15 is significantly different from the assumed value at the time of control design, the operation of the vehicle 10 changes greatly. As described above, since the vehicle body posture may become unstable, the use conditions are severely restricted. In other words, mobility is not comfortable and easy to use.

  On the other hand, in the present embodiment, since the sliding mode control is performed, it is possible to suppress a change in the vehicle body inclination angle during acceleration / deceleration or disturbance action. Further, a substantially constant vehicle operation can be realized with respect to changes in the weight of the occupant 15 and the like. As a result, it is possible to provide the vehicle 10 that is comfortable and easy to use.

  That is, in the present embodiment, the vehicle 10 can travel stably by executing the traveling and posture control processing by the sliding mode control.

  In the travel and attitude control process, the control ECU 20 first executes a state quantity acquisition process (step S1), and the rotational state of the drive wheel 12 and the vehicle body are detected by each sensor, that is, the drive wheel sensor 51 and the vehicle body tilt sensor 41. Get the tilt state.

  Next, the control ECU 20 executes target state determination processing (step S2), and determines the target value of the rotational angular velocity of the drive wheels 12 based on the operation amount of the joystick 31.

  Next, the control ECU 20 executes a sliding plane determination process (step S3), and determines the sliding plane based on the target state determined by the target state determination process.

  Finally, the control ECU 20 executes an actuator output determination process (step S4). Each state quantity acquired by the state quantity acquisition process, the target state determined by the target state determination process, and the sliding plane Based on the sliding plane determined by the determination process, the output of each actuator, that is, the output of the drive motor 52 is determined.

  Next, details of the traveling and attitude control processing will be described. First, the state quantity acquisition process will be described.

  FIG. 5 is a diagram showing a vehicle dynamic model and its parameters according to the first embodiment of the present invention, and FIG. 6 is a flowchart showing an operation of state quantity acquisition processing according to the first embodiment of the present invention.

In the present embodiment, state quantities and parameters are represented by the following symbols. FIG. 5 shows some of the state quantities and parameters.
θ _W : Drive wheel rotation angle (average of two drive wheels) [rad]
θ ₁ : Body tilt angle (vertical axis reference) [rad]
λ _S : Active weight part position (vehicle center point reference) [m]
τ _W : Driving torque (total of two driving wheels) [Nm]
S _S : Active weight part thrust [N]
g: Gravity acceleration [m / s ² ]
m _W : Drive wheel mass (total of two drive wheels) [kg]
R _W : Driving wheel contact radius [m]
I _W : Moment of inertia of driving wheel (total of two driving wheels) [kgm ² ]
D _W : viscosity damping coefficient [Nms / rad] for driving wheel rotation
m ₁ : Body mass (including active weight) [kg]
l ₁ : Body center-of-gravity distance (from axle) [m]
I ₁ : Body inertia moment (around the center of gravity) [kgm ² ]
m _S : Active weight part mass [kg]
I _S : Active weight part inertia moment (around the center of gravity) [kgm ² ]
Here, in the first embodiment of the present invention, the active weight portion does not move, that is, λ _S = 0.

  Next, the target state determination process will be described.

  FIG. 7 is a flowchart showing the operation of the target state determination process in the first embodiment of the present invention.

  In the target state determination process, the main control ECU 21 first acquires a steering operation amount (step S2-1). In this case, the occupant 15 acquires the operation amount of the joystick 31 that is operated to input a travel command such as acceleration, deceleration, turning, on-site rotation, stop, and braking of the vehicle 10.

Subsequently, the main control ECU 21 calculates a target value of the drive wheel rotation angular velocity based on the acquired operation amount of the joystick 31 (step S2-2). For example, a value proportional to the operation amount of the front-rear direction of the joystick 31 as the target value of the vehicle speed, the value obtained by dividing the target value of said vehicle speed by a driving wheel contact radius R _W and the target value of the drive wheel rotation angular velocity .

  Next, the sliding plane determination process will be described.

  FIG. 8 is a diagram showing the sliding plane in the first embodiment of the present invention, and FIG. 9 is a flowchart showing the operation of the sliding plane determination process in the first embodiment of the present invention.

  In the sliding plane determination process, the main control ECU 21 determines a sliding plane as shown in FIG. 8 based on the target value of the drive wheel rotational angular velocity determined by the target state determination process (step S3-1).

  The sliding plane shown in FIG. 8 is a two-dimensional plane in a three-dimensional space having the driving wheel rotation angular velocity, the vehicle body inclination angle, and the vehicle body inclination angular velocity as coordinate axes, and is determined by the following equation (1).

  Further, each component of the unit normal vector of the sliding plane is expressed by the following equation (2).

  In this case, a sliding plane that passes through the target point, which is a point indicating the target state in the space, and is suitable for the mechanical structure is set. The unit normal vector for determining the inclination of the sliding plane is set in advance so as to have an appropriate value by a pole placement method or the like.

  The target state is a state in which the vehicle 10 is traveling at a constant speed and the vehicle body is stable without being tilted. Therefore, the target point indicated by a white circle is that the vehicle body tilt angle and the vehicle body tilt angular velocity are zero. Thus, the drive wheel rotation angular velocity is the drive wheel rotation angular velocity target value.

  Next, the actuator output determination process will be described.

  FIG. 10 is a diagram showing a method for determining the drive torque by the sliding plane in the first embodiment of the present invention, and FIG. 11 is a flowchart showing the operation of the actuator output determination process in the first embodiment of the present invention. is there.

  In the actuator output determination process, the main control ECU 21 first determines the output of the actuator (step S4-1). In this case, the output of the drive motor 52 is determined by the following equation (3) from each target value, the actual state quantity indicating the current state (actual state), and the sliding plane. In FIG. 10, white circles are target points, black circles are actual value points, and dotted circles are points on the sliding plane onto which actual value points are projected. That is, the drive torque is determined by the relative positional relationship between the actual value point, the target point, and the sliding plane.

  The first term on the right side of the equation (4) is a term indicating the target point convergence output in the sliding plane, and the horizontal component (component parallel to the sliding plane) of the state deviation (difference between the actual state and the target state). By giving a drive torque proportional to, the actual value point is converged to the target point so as to slide on the sliding plane.

  The second term is a term indicating the sliding plane convergence output. By applying a driving torque proportional to the distance of the actual value point from the sliding plane, the actual value point is constrained to be close to the sliding plane.

  Furthermore, the third term is a term indicating a sliding plane convergence additional output. By adding a positive or negative output having a constant absolute value according to the relative position between the sliding plane and the real value point, the third term is applied to the sliding plane. Increase the binding force.

  Each control parameter such as feedback gain is determined in advance by a pole placement method or the like.

  Finally, the main control ECU 21 gives a command value to the element control system (step S4-2). In this case, the main control ECU 21 transmits the determined drive torque value as the drive torque command value to the drive wheel control ECU 22.

  As described above, in the present embodiment, the driving torque is set so that the sliding plane is set for the driving wheel rotation angular velocity, the vehicle body inclination angle, and the vehicle body inclination angular velocity, and the state is changed along the set sliding plane. give. Therefore, it is possible to suppress changes in the vehicle body inclination angle during acceleration / deceleration and disturbance. Further, a substantially constant vehicle operation can be realized with respect to changes in the weight of the occupant 15. As a result, it is possible to provide the vehicle 10 that is comfortable and easy to use.

  In this embodiment, the output to be converged on the sliding plane is an output proportional to the distance (the second term on the right side of Equation (3)) and a constant output (the third term on the right side of Equation (3)). Although it is determined by the sum, only one of them may be used. Also, a different nonlinear function may be used. For example, hunting (vibration) of the output value may be suppressed by providing two threshold values in the vicinity of σ = 0 of the sliding plane convergence additional output to provide hysteresis characteristics. Further, a nonlinear function may be used for the target point convergence output in the sliding plane.

  Next, a second embodiment of the present invention will be described. In addition, about the thing which has the same structure as 1st Embodiment, the description is abbreviate | omitted by providing the same code | symbol. The description of the same operation and the same effect as those of the first embodiment is also omitted.

  FIG. 12 is a diagram showing the vehicle body tilt angle target value addition amount in the second embodiment of the present invention, and FIG. 13 is a flowchart showing the operation of target state determination processing in the second embodiment of the present invention.

  If the driving wheel rotational angular velocity is directly controlled, the vehicle body may vibrate greatly. For example, when the driving wheel rotation angular velocity fluctuates due to the influence of road surface unevenness or the like, the control to reduce it strongly affects the attitude control of the vehicle body. Further, when the vehicle speed increases, the viscous resistance of the drive wheels 12 affects the vehicle body posture control, and therefore the vehicle speed and vehicle body posture may not be controlled with high accuracy. Therefore, riding comfort and usability deteriorate as mobility.

  Therefore, in the present embodiment, the sliding resistance control using the viscous resistance of the drive wheel 12 is performed. That is, the vehicle speed is controlled by giving a target value of the vehicle body inclination angle. Specifically, the sliding plane is set only for the vehicle body inclination angle and the vehicle body inclination angular velocity. Further, the target value of the vehicle body tilt angle is given based on the target value of the drive wheel rotation angular velocity. At this time, the vehicle body inclination angle is determined so that the viscous resistance acting with the drive wheel rotation angular velocity (vehicle speed) is canceled by the gravity torque accompanying the vehicle body inclination. Furthermore, if the difference between the actual value of the drive wheel rotation angular velocity and the target value is greater than or equal to a predetermined threshold (threshold) value, the target value of the vehicle body tilt angle is corrected so that the vehicle body is tilted excessively in a direction to reduce the difference. To do.

  Thus, for example, vibration of the vehicle body can be suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with high accuracy. Therefore, it is possible to provide a vehicle that is comfortable and easy to use.

  Next, traveling and attitude control processing in the present embodiment will be described. Note that the outline of the travel and attitude control process and the state quantity acquisition process are the same as those in the first embodiment, and therefore the description thereof will be omitted. The target state determination process, the sliding plane determination process, and the actuator will be omitted. Only the output determination process will be described. First, the target state determination process will be described.

  In the target state determination process, the main control ECU 21 first acquires a steering operation amount (step S2-11). In this case, the occupant 15 acquires the operation amount of the joystick 31 that is operated to input a travel command such as acceleration, deceleration, turning, on-site rotation, stop, and braking of the vehicle 10.

Subsequently, the main control ECU 21 calculates a target value of the drive wheel rotational angular velocity based on the acquired operation amount of the joystick 31 (step S2-12). For example, a value proportional to the operation amount of the front-rear direction of the joystick 31 as the target value of the vehicle speed, the value obtained by dividing the target value of said vehicle speed by a driving wheel contact radius R _W and the target value of the drive wheel rotation angular velocity .

  Finally, the main control ECU 21 calculates the target value of the vehicle body inclination angle from the calculated target value of the drive wheel rotation angular velocity (step S2-13). In this case, the target value of the vehicle body inclination angle is calculated by the following equation (8).

  The target value of the vehicle body inclination angle is determined to be a value that can achieve the target value of the drive wheel rotation angular velocity.

  First, the target value of the vehicle body tilt angle is set so that the counter torque of the viscous resistance torque acting with the rotational angular velocity of the drive wheel is balanced with the gravity torque accompanying the vehicle body tilt (first term on the right side of equation (8)). .

  When the actual value of the rotational angular velocity of the driving wheel is far from the target value, the target value of the vehicle body inclination angle is corrected (second term on the right side of Expression (8)). Specifically, when the actual value of the driving wheel rotation angular velocity is smaller than the target value by a predetermined threshold or more, the vehicle body is tilted further forward by accelerating the vehicle 10 by increasing the target value of the vehicle body inclination angle. . On the other hand, when the actual value of the drive wheel rotation angular velocity is greater than the target value by a predetermined threshold or more, the vehicle body is tilted rearward by decreasing the target value of the vehicle body tilt angle, and the vehicle 10 is decelerated.

  In this embodiment, the target value of the vehicle body inclination angle is determined based on the assumption that the viscous resistance is proportional to the rotational angular velocity of the driving wheel. A target value of the vehicle body inclination angle may be given.

  Further, in the present embodiment, the target value of the vehicle body tilt angle and the additional amount of vehicle body tilt angle are determined using the target value of the drive wheel rotational angular velocity as it is, but a low-pass filter is added to the target value of the drive wheel rotational angular velocity. Over time, the time change may be smoothed. Or you may apply the smoothing function which smoothes a time change. As a result, a sudden change in the vehicle body inclination angle can be suppressed, and riding comfort can be improved.

  Further, in the present embodiment, regardless of whether the driving wheel rotational angular velocity deviation is positive or negative, when the absolute value is equal to or greater than a predetermined threshold, the vehicle body tilt angle addition amount is given at a constant increase rate. The threshold value or the increase rate may be changed. For example, when the driving wheel rotation angular velocity deviation is negative, the deceleration performance can be improved compared to the acceleration performance by reducing the threshold value and increasing the increase rate compared to the positive case. Will improve. In the present embodiment, the vehicle body inclination angle addition amount is defined by a plurality of linear functions, but more ideal acceleration / deceleration characteristics can also be realized by using a nonlinear function.

  Next, the sliding plane determination process will be described.

  FIG. 14 is a diagram showing a sliding plane in the second embodiment of the present invention, and FIG. 15 is a flowchart showing the operation of the sliding plane determination process in the second embodiment of the present invention.

  In the sliding plane determination process of the present embodiment, the main control ECU 21 determines a sliding plane as shown in FIG. 14 based on the target value of the vehicle body inclination angle determined by the target state determination process (step S3). -11).

  The sliding plane shown in FIG. 14 is a one-dimensional plane in a two-dimensional space having the vehicle body tilt angle and the vehicle body tilt angular velocity as coordinate axes, that is, a straight line, and is determined by the following equation (10). Further, each component of the unit normal vector of the sliding plane is expressed by the following equation (11).

  In this case, a sliding plane that passes through the target point and is suitable for the mechanical structure is set. The unit normal vector for determining the inclination of the sliding plane is set in advance so as to have an appropriate value by a pole placement method or the like.

  Also, since the target state is a state in which the vehicle body is stable without tilting, the target point indicated by a white circle is a point where the vehicle body tilt angular velocity is zero and the vehicle body tilt angle is the vehicle body tilt angle target value. It is.

  Next, the actuator output determination process will be described.

  FIG. 16 is a diagram showing a method for determining the drive torque by the sliding plane in the second embodiment of the present invention, and FIG. 17 is a flowchart showing the operation of the actuator output determination process in the second embodiment of the present invention. is there.

  In the actuator output determination process of the present embodiment, the main control ECU 21 first determines the output of the actuator (step S4-11). In this case, the output of the drive motor 52 is determined by the following equation (12) from each target value, the actual state quantity indicating the current state, and the sliding plane. That is, the drive torque is determined by the relative positional relationship between the actual value point, the target point, and the sliding plane.

  The first term on the right-hand side of the equation (12) is a term indicating the target point convergence output in the sliding plane, and the horizontal component (component parallel to the sliding plane) of the state deviation (difference between the actual state and the target state). By giving a drive torque proportional to, the actual value point is converged to the target point so as to slide on the sliding plane.

  The second term is a term indicating the sliding plane convergence output. By applying a driving torque proportional to the distance of the actual value point from the sliding plane, the actual value point is constrained to be close to the sliding plane.

  Furthermore, the third term is a term indicating the sliding plane convergence additional output, and by adding a positive or negative output having a constant absolute value according to the relative position between the sliding plane and the real value point, the third term is output to the sliding plane. Increase restraint.

  Each control parameter such as feedback gain is determined in advance by a pole placement method or the like.

  Finally, the main control ECU 21 gives a command value to the element control system (step S4-12). In this case, the main control ECU 21 transmits the determined drive torque value as the drive torque command value to the drive wheel control ECU 22.

  Thus, in the present embodiment, the sliding resistance control using the viscous resistance of the drive wheels 12 is performed. That is, the vehicle speed is controlled by giving a target value of the vehicle body inclination angle. As a result, the vehicle speed can be indirectly controlled by the drive torque required for the attitude control of the vehicle body without directly controlling the drive wheels 12. Therefore, for example, vibration of the vehicle body can be suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with high accuracy. Therefore, it is possible to provide a vehicle that is comfortable and easy to use.

  In the present embodiment, the output converged on the sliding plane is an output proportional to the distance (the second term on the right side of Equation (12)) and a constant output (the third term on the right side of Equation (12)). Although it is determined by the sum, only one of them may be used. Also, a different nonlinear function may be used. For example, hunting (vibration) of the output value may be suppressed by providing two threshold values in the vicinity of σ = 0 of the sliding plane convergence additional output to provide hysteresis characteristics. Further, a nonlinear function may be used for the target point convergence output in the sliding plane.

  Next, a third embodiment of the present invention will be described. In addition, about the thing which has the same structure as 1st and 2nd embodiment, the description is abbreviate | omitted by providing the same code | symbol. Also, the description of the same operations and effects as those of the first and second embodiments is omitted.

  FIG. 18 is a block diagram showing a configuration of a vehicle control system according to the third embodiment of the present invention.

  In a vehicle having a movable mechanism for the riding section 14, the vehicle body may be tilted more than necessary or the riding section 14 may move during sudden acceleration / deceleration. When the vehicle speed commanded by the occupant 15 is realized by feedback control of the driving wheel rotation angular velocity, the inertial force or the anti-torque of the driving torque accompanying the acceleration / deceleration of the vehicle 10 affects the posture control of the vehicle body. For example, when making a sudden start, the vehicle body is tilted greatly or the riding portion 14 is moved greatly, and then the vehicle body is raised or the riding portion 14 is returned to its original position to accelerate. In addition, the vehicle body and the riding section 14 may vibrate greatly due to disturbances such as resistance caused by road surface unevenness. Furthermore, when the weight of the occupant 15 is significantly different from the set value at the time of control design, the operation of the vehicle 10 changes greatly, and the vehicle body posture may become unstable, so that the use conditions are severely restricted. Therefore, riding comfort and usability deteriorate as mobility.

  Therefore, in the present embodiment, the robust stability of the running and attitude control is improved by applying the sliding mode control in the vehicle having the possible mechanism of the riding section 14. Specifically, two sliding planes are set for the driving wheel rotation angular velocity, the vehicle body inclination angle, the vehicle body inclination angular velocity, the active weight portion position, and the active weight portion moving speed. Then, a drive torque and an active weight portion thrust are applied so as to change the state along each sliding plane. That is, the driving torque and the active weight portion thrust are determined based on the actual state, the target state, and the relative positional relationship between the two sliding planes.

  Thereby, the change of the vehicle body inclination angle or the position of the riding section 14 during acceleration / deceleration or disturbance action can be suppressed. Further, a substantially constant vehicle operation can be realized with respect to changes in the weight of the occupant 15 and the like.

  In the present embodiment, the riding section 14 functions as an active weight section and is movable relative to the main body section 11 in the front-rear direction of the vehicle 10, in other words, relative to the tangential direction of the vehicle body rotation circle. It is attached to the main body 11 so as to be movable.

  Here, the active weight part has a certain amount of mass, and actively corrects the position of the center of gravity of the vehicle 10 by moving it back and forth with respect to the main body part 11. The active weight portion does not necessarily need to be the riding portion 14. For example, the active weight portion may be a device in which a heavy peripheral device such as a battery is movably attached to the main body portion 11, a weight, a weight (Weight), a device in which a dedicated weight member such as a balancer is movably attached to the main body 11 may be used. Moreover, you may use together the boarding part 14, a heavy peripheral device, an exclusive weight member, etc. In the present embodiment, for the sake of explanation, an example will be described in which the riding section 14 in the state where the occupant 15 is boarded functions as an active weight section.

  And the said boarding part 14 is attached to the main-body part 11 via the moving mechanism which is not shown in figure. The moving mechanism includes a low-resistance linear moving mechanism such as a linear guide device and an active weight part motor 62 as an active weight part actuator. The active weight part motor 62 drives the riding part 14, and the main body part 11. The vehicle is moved back and forth in the vehicle traveling direction. As the active weight actuator, for example, a hydraulic motor, a linear motor, or the like can be used. However, here, the description will be made assuming that the active weight motor 62 that is a rotary electric motor is used.

  The linear guide device includes, for example, a guide rail attached to the main body 11, a carriage attached to the riding portion 14 and sliding along the guide rail, a ball, a roller, and the like interposed between the guide rail and the carriage. Rolling elements. In the guide rail, two track grooves are formed linearly along the longitudinal direction on the left and right side surfaces thereof. Further, the cross section of the carriage is formed in a U-shape, and two track grooves are formed on the inner sides of the two opposing side surfaces so as to face the track grooves of the guide rail. The rolling elements are incorporated between the raceway grooves, and roll in the raceway grooves with the relative linear motion of the guide rail and the carriage. The carriage is formed with a return passage that connects both ends of the raceway groove, and the rolling elements circulate through the raceway groove and the return passage.

  The linear guide device includes a brake or a clutch that fastens the movement of the linear guide device. When the operation of the riding section 14 is unnecessary, such as when the vehicle 10 is stopped, the relative positional relationship between the main body section 11 and the riding section 14 is maintained by fixing the carriage to the guide rail with a brake. . When the operation is necessary, the brake is released and the distance between the reference position on the main body 11 side and the reference position on the riding section 14 is controlled to be a predetermined value.

  As shown in the figure, the control ECU 20 in the present embodiment includes arithmetic means such as a CPU and MPU, storage means such as a magnetic disk and a semiconductor memory, an input / output interface, and the like, and controls the operation of each part of the vehicle 10. An active weight control ECU 23 that is a computer system is provided.

  The main control ECU 21 functions as a part of the active weight part control system 60 that controls the operation of the riding part 14 that is the active weight part together with the active weight part control ECU 23, the active weight part sensor 61, and the active weight part motor 62. To do. The active weight part sensor 61 is composed of an encoder or the like, functions as an active weight part movement state measuring device, detects the active weight part position and / or active weight part movement speed indicating the movement state of the riding part 14, and performs main control. It transmits to ECU21. Further, the main control ECU 21 transmits an active weight part thrust command value to the active weight part control ECU 23, and the active weight part control ECU 23 sends an input voltage corresponding to the received active weight part thrust command value to the active weight part motor. 62. The active weight motor 62 applies thrust to the riding section 14 to translate the riding section 14 in accordance with the input voltage, thereby functioning as an active weight actuator.

  The main control ECU 21 functions as a part of the vehicle body control system 40 that controls the posture of the vehicle body together with the drive wheel control ECU 22, the active weight unit control ECU 23, the vehicle body inclination sensor 41, the drive motor 52, and the active weight unit motor 62. . The vehicle body tilt sensor 41 includes an acceleration sensor, a gyro sensor, and the like, and functions as a vehicle body tilt state measuring device. . The main control ECU 21 transmits a drive torque command value to the drive wheel control ECU 22 and transmits an active weight portion thrust command value to the active weight portion control ECU 23.

  Furthermore, a travel command is input from the joystick 31 of the input device 30 to the main control ECU 21. Then, the main control ECU 21 transmits a drive torque command value to the drive wheel control ECU 22 and transmits an active weight portion thrust command value to the active weight portion control ECU 23.

  Since the configuration of other points is the same as that of the first and second embodiments, the description thereof is omitted.

  Next, the operation of the vehicle 10 in the present embodiment will be described. Note that the outline of the travel and attitude control processing and the target state determination processing are the same as those in the first embodiment, so the description thereof will be omitted, and the state quantity acquisition processing, sliding plane determination processing, and actuator will be omitted. Only the output determination process will be described. First, the state quantity acquisition process will be described.

FIG. 19 is a flowchart showing the state quantity acquisition processing in the third embodiment of the present invention.

  Next, the sliding plane determination process will be described.

  FIG. 20 is a flowchart showing the operation of the sliding plane determination process in the third embodiment of the present invention.

  In the sliding plane determination process of the present embodiment, the main control ECU 21 is expressed by the following equations (17) and (18) based on the target value of the drive wheel rotation angular velocity determined by the target state determination process. Two sliding planes are determined (step S3-21). In the present embodiment, the sliding plane is a four-dimensional plane in a five-dimensional space having the driving wheel rotation angular velocity, the vehicle body inclination angle, the vehicle body inclination angular velocity, the active weight portion position, and the active weight portion moving speed as coordinate axes. One sliding plane is represented by equation (17), and the second sliding plane is represented by equation (18). Each component of the unit normal vector of the first sliding plane is expressed by the following equation (19), and each component of the unit normal vector of the second sliding plane is expressed by the following equation (20).

  In this case, first and second sliding planes that pass through the target point and are suitable for the mechanical structure are set. The unit normal vectors that determine the inclinations of the first and second sliding planes are set in advance so as to have appropriate values by the pole placement method or the like.

  Next, the actuator output determination process will be described.

  FIG. 21 is a flowchart showing the operation of the actuator output determination process in the third embodiment of the present invention.

  In the actuator output determination process of the present embodiment, the main control ECU 21 first determines the output of each actuator (step S4-21). In this case, the outputs of the drive motor 52 and the active weight unit motor 62 are determined by the following equations (21) and (22) from each target value, the actual state quantity indicating the current state, and the two sliding planes. . That is, the driving torque and the active weight portion thrust are determined based on the actual state, the target state, and the relative positional relationship between the two sliding planes. The drive torque that is the output of the drive motor 52 is determined by the following equation (21), and the active weight portion thrust that is the output of the active weight portion motor 62 is determined by the following equation (22).

  The first term on the right side of the equations (21) and (22) is a term indicating the target point convergence output in the sliding plane, and the horizontal component of the state deviation (difference between the actual state and the target state) (in the sliding plane). By applying a driving torque or an active weight portion thrust proportional to the parallel component), the actual value point is converged to the target point so as to slide on the sliding plane.

  The second term is a term indicating the sliding plane convergence output. By applying a driving torque or an active weight portion thrust proportional to the distance from the sliding plane of the actual value point, the actual value point is brought closer to the sliding plane. to bound.

  Furthermore, the third term is a term indicating a sliding plane convergence additional output. By adding a positive or negative output having a constant absolute value according to the relative position between the sliding plane and the real value point, the third term is applied to the sliding plane. Increase the binding force.

  Each control parameter such as feedback gain is determined in advance by a pole placement method or the like.

  Finally, the main control ECU 21 gives a command value to each element control system (step S4-22). In this case, the main control ECU 21 transmits the determined drive torque value and active weight part thrust as the drive torque command value and active weight part thrust command value to the drive wheel control ECU 22 and the active weight part control ECU 23.

  As described above, in the present embodiment, the robust stability of the running and posture control is improved by applying the sliding mode control to the vehicle in which the riding section 14 is movable. Therefore, it is possible to suppress changes in the vehicle body inclination angle and the position of the riding section 14 during acceleration / deceleration and disturbance. Further, a substantially constant vehicle operation can be realized with respect to changes in the weight of the occupant 15 and the like. Therefore, it is possible to provide a vehicle that is comfortable and easy to use.

  In the present embodiment, the output converged on the sliding plane is divided into an output proportional to the distance (second term on the right side of equations (21) and (22)) and a constant output (of equations (21) and (22)). Although it is determined by the sum of the third term on the right side), only one of them may be used. Also, a different nonlinear function may be used. For example, hunting (vibration) of the output value may be suppressed by providing two threshold values in the vicinity of σ = 0 of the sliding plane convergence additional output to provide hysteresis characteristics. Further, a nonlinear function may be used for the target point convergence output in the sliding plane.

  Next, a fourth embodiment of the present invention will be described. In addition, about the thing which has the same structure as the 1st-3rd embodiment, the description is abbreviate | omitted by providing the same code | symbol. Explanation of the same operations and effects as those of the first to third embodiments is also omitted.

  FIG. 22 is a flowchart showing the operation of the sliding plane determination process in the fourth embodiment of the present invention.

  Even when the sliding mode control is applied, the vehicle body is tilted to some extent because the vehicle body is balanced by the vehicle body tilt and the riding section movement. As a result, the ride quality becomes poor as mobility. Therefore, it is desirable that the vehicle body is not tilted as much as possible and is balanced only by the parallel movement of the riding section.

  Therefore, in the present embodiment, when sliding mode control is applied to a vehicle in which the riding section 14 is movable, the influence of the drive wheels 12 is imposed on the moving mechanism of the riding section 14 to thereby tilt the vehicle body. Suppress. Specifically, a first sliding plane is set with respect to the vehicle body inclination angle and the vehicle body inclination angular velocity, and a drive torque is applied so that the same state quantity changes along the first sliding plane. Further, a second sliding plane is set for the driving wheel rotation angular velocity, the active weight portion position, and the active weight portion moving speed, and the active weight portion thrust is applied so that the same state quantity changes along the second sliding plane. By separating the vehicle body tilt control from the drive wheel 12 control, the upright posture maintenance control can be performed more easily and firmly. Actually, the drive wheel 12 cannot be directly controlled by the active weight portion thrust, but the riding portion 14 is moved by the active weight portion thrust, which is a counter torque of the drive torque for suppressing the vehicle body inclination. As a result, traveling control is achieved.

  Thereby, the change of the vehicle body inclination angle during acceleration / deceleration or disturbance action can be further suppressed, and a vehicle that can travel more comfortably can be provided.

  Next, traveling and attitude control processing in the present embodiment will be described. Note that the outline of the travel and attitude control processing, the state quantity acquisition processing, and the target state determination processing are the same as those in the third embodiment, and thus the description thereof will be omitted, and the sliding plane determination processing will be omitted. Only the actuator output determination process will be described. First, the sliding plane determination process will be described.

  In the sliding plane determination process of the present embodiment, the main control ECU 21 is represented by the following equations (30) and (31) based on the target value of the drive wheel rotation angular velocity determined by the target state determination process. Two sliding planes are determined (step S3-31). In the present embodiment, the first sliding plane is a one-dimensional plane in a two-dimensional space having the vehicle body tilt angle and the vehicle body tilt angular velocity as coordinate axes, that is, a straight line, and is represented by the following equation (30). . The second sliding plane is a two-dimensional plane in a three-dimensional space having the driving wheel rotation angular velocity, the active weight portion position, and the active weight portion moving speed as coordinate axes, and is represented by the following equation (31). Each component of the unit normal vector of the first sliding plane is represented by the following equation (32), and each component of the unit normal vector of the second sliding plane is represented by the following equation (33).

  In this case, first and second sliding planes that pass through the target point and are suitable for the mechanical structure are set. The unit normal vectors that determine the inclinations of the first and second sliding planes are set in advance so as to have appropriate values by the pole placement method or the like.

  Next, the actuator output determination process will be described.

  FIG. 23 is a flowchart showing the operation of the actuator output determination process in the fourth embodiment of the present invention.

  In the actuator output determination process of the present embodiment, the main control ECU 21 first determines the output of each actuator (step S4-31). In this case, the outputs of the drive motor 52 and the active weight unit motor 62 are determined by the following equations (34) and (35) from each target value, the actual state quantity indicating the current state, and the two sliding planes. . That is, the driving torque and the active weight portion thrust are determined based on the actual state, the target state, and the relative positional relationship between the two sliding planes. The drive torque that is the output of the drive motor 52 is determined by the following equation (34), and the active weight portion thrust that is the output of the active weight portion motor 62 is determined by the following equation (35).

  The first term on the right-hand side of the equations (34) and (35) is a term indicating the target point convergence output in the sliding plane, and the horizontal component of the state deviation (difference between the actual state and the target state) (in the sliding plane) By applying a driving torque or an active weight portion thrust proportional to the parallel component), the actual value point is converged to the target point so as to slide on the sliding plane.

  The second term is a term indicating the sliding plane convergence output. By applying a driving torque or an active weight portion thrust proportional to the distance from the sliding plane of the actual value point, the actual value point is brought closer to the sliding plane. to bound.

  Furthermore, the third term is a term indicating the sliding plane convergence additional output, and by adding a positive or negative output having a constant absolute value according to the relative position between the sliding plane and the real value point, the third term is output to the sliding plane. Increase restraint.

  Each control parameter such as feedback gain is determined in advance by a pole placement method or the like.

  Finally, the main control ECU 21 gives a command value to each element control system (step S4-32). In this case, the main control ECU 21 transmits the determined drive torque value and active weight part thrust as the drive torque command value and active weight part thrust command value to the drive wheel control ECU 22 and the active weight part control ECU 23.

  As described above, in the present embodiment, when sliding mode control is further applied to a vehicle in which the riding section 14 is movable, the movement mechanism of the riding section 14 is burdened with the influence of the drive wheels 12. , Suppress the body tilt. That is, by separating the vehicle body tilt control from the drive wheel 12 control, the upright posture maintenance control can be performed more easily and firmly. Therefore, the riding part 14 is moved by the active weight part thrust, and thereby the traveling control is achieved by the counter-torque of the driving torque for suppressing the vehicle body inclination. Therefore, it is possible to further suppress changes in the vehicle body inclination angle during acceleration / deceleration and disturbance, and to provide a vehicle that can travel more comfortably.

  In the present embodiment, the output converged on the sliding plane is divided into an output proportional to the distance (second term on the right side of Expressions (34) and (35)) and a constant output (Expressions (34) and (35)). Although it is determined by the sum of the third term on the right side), only one of them may be used. Also, a different nonlinear function may be used. For example, hunting (vibration) of the output value may be suppressed by providing two threshold values in the vicinity of the sliding plane convergence additional output σ = 0 to provide hysteresis characteristics. Further, a nonlinear function may be used for the target point convergence output in the sliding plane.

  Next, a fifth embodiment of the present invention will be described. In addition, about the thing which has the same structure as 1st-4th embodiment, the description is abbreviate | omitted by providing the same code | symbol. Explanation of the same operations and effects as those of the first to fourth embodiments is also omitted.

  FIG. 24 is a diagram showing the active weight part position target value addition amount in the fifth embodiment of the present invention, and FIG. 25 is a flowchart showing the operation of target state determination processing in the fifth embodiment of the present invention. .

  If the driving wheel rotation angular velocity is directly controlled, the vehicle body or the riding section 14 may vibrate greatly. For example, when the driving wheel rotation angular velocity fluctuates due to the influence of road surface unevenness or the like, the control to reduce it strongly affects the attitude control of the vehicle body. Further, when the vehicle speed increases, the viscous resistance of the drive wheels 12 affects the vehicle body posture control, and therefore the vehicle speed and vehicle body posture may not be controlled with high accuracy. Therefore, riding comfort and usability deteriorate as mobility.

  Therefore, in the present embodiment, the sliding resistance control using the viscous resistance of the drive wheel 12 is performed. That is, the vehicle speed is controlled by giving a target value of the active weight portion position. Specifically, the second sliding plane is set only for the active weight part position and the active weight part moving speed. Further, based on the target value of the driving wheel rotation angular velocity, the target value of the active weight portion position is given. At this time, the position of the active weight portion is determined so that the viscous resistance acting with the rotational angular velocity (vehicle speed) of the driving wheel is canceled by the gravitational torque accompanying the displacement of the active weight portion. Further, when the difference between the actual value of the driving wheel rotational angular velocity and the target value is equal to or greater than a predetermined threshold value, the target value of the active weight part position is corrected so that the active weight part is excessively moved in a direction to reduce the difference. .

  Thus, for example, vibration of the vehicle body can be suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with high accuracy. Therefore, it is possible to provide a vehicle that is comfortable and easy to use.

  Next, traveling and attitude control processing in the present embodiment will be described. Note that the outline of the travel and attitude control processing and the state quantity acquisition processing are the same as those in the third embodiment, and thus the description thereof will be omitted, and the target state determination processing, sliding plane determination processing, and actuator will be omitted. Only the output determination process will be described. First, the target state determination process will be described.

  In the target state determination process of the present embodiment, the main control ECU 21 first acquires a steering operation amount (step S2-21). In this case, the occupant 15 acquires the operation amount of the joystick 31 that is operated to input a travel command such as acceleration, deceleration, turning, on-site rotation, stop, and braking of the vehicle 10.

Subsequently, the main control ECU 21 calculates a target value of the drive wheel rotation angular velocity based on the acquired operation amount of the joystick 31 (step S2-22). For example, a value proportional to the operation amount of the front-rear direction of the joystick 31 as the target value of the vehicle speed, the value obtained by dividing the target value of said vehicle speed by a driving wheel contact radius R _W and the target value of the drive wheel rotation angular velocity .

  Finally, the main control ECU 21 calculates the target value of the active weight portion position from the calculated target value of the drive wheel rotation angular velocity (step S2-23). In this case, the target value of the position of the active weight part is calculated by the following equation (43).

  The target value of the active weight portion position is determined to be a value that can achieve the target value of the drive wheel rotation angular velocity.

  First, the target value of the vehicle body inclination angle is set so that the counter torque of the viscous resistance torque acting with the driving wheel rotation angular velocity is balanced with the gravity torque accompanying the displacement of the active weight portion position (in the right side of the equation (43)) Section 1).

  When the actual value of the rotational angular velocity of the driving wheel is far from the target value, the target value of the active weight portion position is corrected (second term on the right side of Expression (43)). Specifically, when the actual value of the rotational angular velocity of the driving wheel is smaller than the target value by a predetermined threshold or more, the active weight portion is moved further forward by increasing the target value of the active weight portion position, so that the vehicle 10 is accelerated. On the other hand, if the actual value of the rotational angular velocity of the drive wheels is greater than the target value by a predetermined threshold or more, the target value of the active weight part position is decreased to move the active weight part position further rearward. Decelerate.

  In this embodiment, the target value of the active weight part position is determined based on the assumption that the viscous resistance is proportional to the rotational angular velocity of the driving wheel. A target value of a suitable active weight part position may be given.

  In the present embodiment, the target value of the active weight portion position and the additional amount of the active weight portion position are determined using the target value of the driving wheel rotational angular velocity as it is. The time change may be smoothed by applying a filter. Or you may apply the smoothing function which smoothes a time change. Thereby, a sudden change in the position of the active weight portion can be suppressed, and riding comfort can be improved.

  Further, in the present embodiment, the active weight portion position addition amount is given at a constant increase rate when the absolute value is equal to or greater than a predetermined threshold regardless of whether the driving wheel rotation angular velocity deviation is positive or negative. The threshold value or the increase rate may be changed accordingly. For example, when the driving wheel rotation angular velocity deviation is negative, the deceleration performance can be improved compared to the acceleration performance by reducing the threshold value and increasing the increase rate compared to the positive case. Will improve. In the present embodiment, the active weight part position addition amount is defined by a plurality of linear functions, but more ideal acceleration / deceleration characteristics can also be realized by using a nonlinear function.

  Next, the sliding plane determination process will be described.

  FIG. 26 is a flowchart showing the operation of the sliding plane determination process in the fifth embodiment of the present invention.

  In the sliding plane determination process of the present embodiment, the main control ECU 21 is represented by the following equations (45) and (46) based on the target value of the drive wheel rotation angular velocity determined by the target state determination process. Two sliding planes are determined (step S3-41). In the present embodiment, the first sliding plane is a one-dimensional plane in a two-dimensional space having the vehicle body tilt angle and the vehicle body tilt angular velocity as coordinate axes, that is, a straight line, and is represented by the following equation (45). . The second sliding plane is a one-dimensional plane in a two-dimensional space having the active weight part position and the active weight part moving speed as coordinate axes, that is, a straight line, and is represented by the following equation (46). Each component of the unit normal vector of the first sliding plane is represented by the following equation (47), and each component of the unit normal vector of the second sliding plane is represented by the following equation (48).

  In this case, first and second sliding planes that pass through the target point and are suitable for the mechanical structure are set. The unit normal vectors that determine the inclinations of the first and second sliding planes are set in advance so as to have appropriate values by the pole placement method or the like.

  Next, the actuator output determination process will be described.

  FIG. 27 is a flowchart showing the operation of the actuator output determination process in the fifth embodiment of the invention.

  In the actuator output determination process of the present embodiment, the main control ECU 21 first determines the output of each actuator (step S4-41). In this case, the outputs of the drive motor 52 and the active weight unit motor 62 are determined by the following equations (49) and (50) from each target value, the actual state quantity indicating the current state, and the two sliding planes. . That is, the driving torque and the active weight portion thrust are determined based on the actual state, the target state, and the relative positional relationship between the two sliding planes. The drive torque that is the output of the drive motor 52 is determined by the following equation (49), and the active weight portion thrust that is the output of the active weight portion motor 62 is determined by the following equation (50).

  The first term on the right side of the equations (49) and (50) is a term indicating the target point convergence output in the sliding plane, and the horizontal component of the state deviation (difference between the actual state and the target state) (in the sliding plane) By applying a driving torque or an active weight portion thrust proportional to the parallel component), the actual value point is converged to the target point so as to slide on the sliding plane.

  The second term is a term indicating the sliding plane convergence output. By applying a driving torque or an active weight portion thrust proportional to the distance from the sliding plane of the actual value point, the actual value point is brought closer to the sliding plane. to bound.

  Furthermore, the third term is a term indicating the sliding plane convergence additional output, and by adding a positive or negative output having a constant absolute value according to the relative position between the sliding plane and the real value point, the third term is output to the sliding plane. Increase restraint.

  Each control parameter such as feedback gain is determined in advance by a pole placement method or the like.

  Finally, the main control ECU 21 gives a command value to each element control system (step S4-42). In this case, the main control ECU 21 transmits the determined drive torque value and active weight part thrust as the drive torque command value and active weight part thrust command value to the drive wheel control ECU 22 and the active weight part control ECU 23.

  Thus, in the present embodiment, when sliding mode control is applied to a vehicle in which the riding section 14 is movable, the vehicle speed is controlled by giving the target value of the active weight section position. Thereby, the vehicle speed can be controlled by the drive torque without directly controlling the drive wheels 12. Therefore, vibration of the vehicle body can be suppressed even when traveling on an uneven road surface. Further, the vehicle speed and the vehicle body posture can be controlled with high accuracy. Therefore, it is possible to provide a vehicle that is comfortable and easy to use.

  In the present embodiment, the output converged on the sliding plane is divided into an output proportional to the distance (second term on the right side of equations (49) and (50)) and a constant output (equations (49) and (50)). Although it is determined by the sum of the third term on the right side), only one of them may be used. Also, a different nonlinear function may be used. For example, hunting (vibration) of the output value may be suppressed by providing two threshold values in the vicinity of σ = 0 of the sliding plane convergence additional output to provide hysteresis characteristics. Further, a nonlinear function may be used for the target point convergence output in the sliding plane.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

It is the schematic which shows the structure of the vehicle in the 1st Embodiment of this invention, and is a figure which shows the state which is carrying out acceleration advance in the state which the passenger | crew got on. It is a block diagram which shows the structure of the control system of the vehicle in the 1st Embodiment of this invention. It is a figure explaining the difference between linear feedback control and sliding mode control. It is a flowchart which shows operation | movement of the driving | running | working and attitude | position control processing of the vehicle in the 1st Embodiment of this invention. It is a figure which shows the dynamic model of the vehicle in the 1st Embodiment of this invention, and its parameter. It is a flowchart which shows the operation | movement of the acquisition process of the state quantity in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the target state in the 1st Embodiment of this invention. It is a figure which shows the sliding plane in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the sliding plane in the 1st Embodiment of this invention. It is a figure which shows the method of determining a drive torque by the sliding plane in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the actuator output in the 1st Embodiment of this invention. It is a figure which shows the vehicle body inclination angle target value addition amount in the 2nd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the target state in the 2nd Embodiment of this invention. It is a figure which shows the sliding plane in the 2nd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the sliding plane in the 2nd Embodiment of this invention. It is a figure which shows the method of determining a driving torque by the sliding plane in the 2nd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the actuator output in the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the control system of the vehicle in the 3rd Embodiment of this invention. It is a flowchart which shows the operation | movement of the acquisition process of the state quantity in the 3rd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the sliding plane in the 3rd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the actuator output in the 3rd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the sliding plane in the 4th Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the actuator output in the 4th Embodiment of this invention. It is a figure which shows the active weight part position target value addition amount in the 5th Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the target state in the 5th Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the sliding plane in the 5th Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the actuator output in the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle 12 Drive wheel 14 Boarding part 20 Control ECU
31 Joystick

Claims (10)

The car body,
A drive wheel rotatably mounted on the vehicle body;
A vehicle control device for controlling the attitude of the vehicle body by controlling the drive torque applied to the drive wheels,
The vehicle control device determines a target state of the driving wheel or the vehicle body based on a steering operation amount of the control device, determines a sliding plane based on the determined target state, and determines an actual state, the target state, and the sliding A vehicle characterized in that the driving torque is determined by a positional relationship with a plane.   2. The vehicle according to claim 1, wherein the sliding plane is a plane that guides a control transition path to the target state, and is a hyperplane that is set in a space having coordinates of the state quantities of the real state and the target state. . The target state is a state in which the rotational angular velocity of the drive wheel becomes a target value,
The vehicle according to claim 1 or 2, wherein the sliding plane is set in a space having coordinates of a rotational angular velocity of the driving wheel, an inclination angle of the vehicle body, and an inclination angular velocity of the vehicle body. The target state is a state in which the inclination angle of the vehicle body becomes a target value,
The vehicle according to claim 1, wherein the sliding plane is set in a space having coordinates of an inclination angle of the vehicle body and an inclination angular velocity of the vehicle body. The target value of the tilt angle of the vehicle body is the sum of a reference value determined by the target value of the rotational angular speed of the drive wheel and a correction value determined by the difference between the target value of the rotational angular speed of the drive wheel and the actual value. And
When the difference between the target value and the actual value of the rotational angular velocity of the drive wheel is greater than a predetermined threshold, the correction value is the vehicle body in a direction that reduces the difference between the target value and the actual value of the rotational angular velocity of the drive wheel. The vehicle according to claim 4, wherein the vehicle is a value that inclines an excessive amount. An active weight portion movably attached to the vehicle body;
The vehicle control device controls the posture of the vehicle body by controlling at least one of the driving torque and the position of the active weight portion, and the vehicle control device controls the posture of the vehicle body according to a positional relationship between the actual state, the target state, and a sliding plane. The vehicle according to claim 1, wherein the driving torque and the thrust of the active weight portion are determined. The target state is a state in which the rotational angular velocity of the drive wheel becomes a target value,
The sliding plane is a space having at least two coordinates of a rotational angular velocity of the driving wheel, an inclination angle of the vehicle body, an inclination angular velocity of the vehicle body, a position of the active weight portion, and a moving speed of the active weight portion. The vehicle according to claim 6, comprising two planes to be set. The target state is a state in which the rotational angular velocity of the drive wheel becomes a target value,
The sliding plane includes a first sliding plane set in a space having coordinates of the vehicle body inclination angle and the vehicle body inclination angular velocity, the rotational angular velocity of the driving wheel, the position of the active weight portion, and the active weight portion. The vehicle according to claim 6, comprising a second sliding plane set in a space having the moving speed as coordinates. The target state is a state where the position of the active weight part is a target value,
The sliding plane has a first sliding plane set in a space having the vehicle body inclination angle and the vehicle body inclination angular velocity as coordinates, and the position of the active weight portion and the moving speed of the active weight portion as coordinates. The vehicle according to claim 6, comprising a second sliding plane set in a space. The target value of the position of the active weight portion is a reference value determined by the target value of the rotational angular velocity of the driving wheel and a correction value determined by the difference between the target value of the rotational angular velocity of the driving wheel and the actual value. Is sum,
The correction value is set so as to reduce the difference between the target value and the actual value of the rotational angular velocity of the driving wheel only when the difference between the target value and the actual value of the rotational angular velocity of the driving wheel is larger than a predetermined threshold. The vehicle according to claim 9, wherein the vehicle is a value that moves the active weight part excessively.

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