JP2010100137A - Vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the running condition and the posture of a vehicle body with high accuracy even under the high-speed running and to allow a vehicle to safely and comfortably run under various kinds of running conditions by correcting the driving torque of driving wheels and the position of the center of gravity of the vehicle body according to the running speed of the vehicle. <P>SOLUTION: A vehicle has driving wheels 12 which are rotatably mounted on a vehicle body, and a vehicle control device for controlling the posture of the vehicle body by controlling the driving torque to be given to the driving wheels 12. The vehicle control device relatively moves the center of gravity of the vehicle body to the driving wheels by the amount according to the rotational angular velocity of the driving wheels in the advancing direction of the driving wheels. <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, detects a change in the posture of the vehicle body due to the movement of the center of gravity of the driver, and drives the vehicle body attached to a single spherical drive wheel. Techniques for vehicles that move while being controlled have been proposed (see, for example, Patent Document 1).

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

  However, in the conventional vehicle, the vehicle body is maintained in an inverted posture by controlling the position of the center of gravity of the vehicle body in accordance with the acceleration of the vehicle. Even when the vehicle is traveling (the vehicle acceleration is zero), an error in controlling the traveling speed and the vehicle body posture becomes large due to the influence of air resistance acting on the vehicle body. As a result, maneuverability and ride comfort may deteriorate.

  The present invention solves the problems of the conventional vehicle and appropriately corrects the driving torque of the driving wheels and the center of gravity of the vehicle body according to the traveling speed of the vehicle, so that the traveling state can be achieved even during high-speed traveling. It is another object of the present invention to provide a vehicle that can control the vehicle body posture with high accuracy and can travel safely and comfortably under various traveling conditions.

  For this purpose, the vehicle of the present invention includes a drive wheel rotatably attached to the vehicle body, and a vehicle control device that controls a drive torque applied to the drive wheel to control the posture of the vehicle body, The vehicle control device moves the center of gravity of the vehicle body relative to the driving wheel by an amount corresponding to the rotational angular velocity of the driving wheel in the traveling direction of the driving wheel.

  In another vehicle of the present invention, the vehicle control device moves the center of gravity of the vehicle body by tilting the vehicle body.

  Still another vehicle of the present invention further includes an active weight portion movably attached to the vehicle body, and the vehicle control device moves the active weight portion to move the center of gravity of the vehicle body. Move.

  Still another vehicle according to the present invention further includes estimation means for estimating a speed-dependent resistance torque, which is a resistance torque acting on the drive wheel and / or the vehicle body, according to the vehicle speed, based on the rotational angular speed of the drive wheel. The vehicle control device moves the center of gravity of the vehicle body according to the speed-dependent resistance torque estimated by the estimation means.

  In still another vehicle of the present invention, the estimating means further includes a vehicle body air resistance torque that is a torque of an air resistance acting on the vehicle body and / or a drive wheel friction that is a friction resistance against rotation of the drive wheel. Estimate resistance and / or anti-torque of said air resistance.

  Still another vehicle according to the present invention includes 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. An air speed measuring means for measuring an air speed, wherein the vehicle control device is configured such that the center of gravity of the vehicle body is relative to the drive wheel in the air speed direction by an amount corresponding to the magnitude of the air speed. Move.

  According to the configuration of the first aspect, the travel speed of the vehicle is easily estimated, and the center of gravity position of the vehicle body is moved to an appropriate position according to the size thereof. It can be controlled stably with accuracy.

  According to the configuration of the second aspect, the center of gravity of the vehicle body can be easily moved without adding an extra mechanism for moving the center of gravity.

  According to the configuration of the third aspect, the position of the center of gravity of the vehicle body can be moved without tilting the vehicle body, so that riding comfort is improved.

  According to the configuration of the fourth aspect, the influence on the vehicle by the traveling speed is estimated, and the center of gravity position of the vehicle body is appropriately set accordingly, so that the traveling state and the vehicle body posture can be controlled with higher accuracy. it can.

  According to the configuration of the fifth aspect, the traveling state and the vehicle body posture can be controlled with higher accuracy by more strictly estimating the influence of the traveling speed on the vehicle.

  According to the fifth aspect of the present invention, since the correct traveling speed can be obtained even when the drive wheel is idling, it is possible to stably control the traveling state and the vehicle body posture in accordance with the traveling speed.

  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 the figure, reference numeral 10 denotes a vehicle according to the present embodiment, which has a body portion 11, a driving wheel 12, a support portion 13, and a riding portion 14 on which an occupant 15 rides, and uses the posture control of an inverted pendulum. Control the attitude of the car body. The vehicle 10 can tilt the vehicle body forward and backward. 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 forward in the traveling direction.

  The drive wheel 12 is rotatably supported by 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 shaft of the drive wheel 12 extends in a direction perpendicular to the drawing of FIG. 1, and the drive wheel 12 rotates about the shaft. 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. And, in the main body part 11, the riding part 14 functioning as an active weight part can be translated relative to the main body part 11 in the longitudinal direction of the vehicle 10, in other words, the tangential direction of the vehicle body rotation circle It is attached so that it can move relatively.

  Here, the active weight portion has a certain amount of mass and translates with respect to the main body portion 11, that is, actively moves the front and rear to correct the position of the center of gravity of the vehicle 10. The active weight portion does not necessarily have 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 attached to the main body portion 11 so as to be translatable. (Weight), a device in which a dedicated weight member such as a balancer is attached to the main body 11 so as to be translatable 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 a state in which the occupant 15 is boarded functions as an active weight section. However, the occupant 15 is not necessarily on the riding section 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, and is attached to the main body part 11 via a moving mechanism (not shown). ing.

  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. It is designed to move back and forth in the direction of travel. 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, and a ball and a roller interposed between the guide rail and the carriage. And rolling elements such as. 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.

  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, another device such as a jog dial, a touch panel, or a push button may be used as the target travel state acquisition device instead of the joystick 31. You can also.

  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, a drive wheel control ECU 22, and an active weight unit control ECU 23. The control ECU 20, main control ECU 21, driving wheel control ECU 22 and active weight unit control ECU 23 include calculation means such as a CPU and MPU, storage means such as a magnetic disk and semiconductor memory, input / output interfaces, and the like. A computer system that controls the operation. For example, the computer system is disposed in the main body 11, but may be disposed in the support portion 13 or the riding portion 14. The main control ECU 21, the drive wheel control ECU 22, and the active weight control ECU 23 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 rotation angular velocity indicating a rotation state of the drive wheel 12, and transmits it to the main control ECU 21. To do. 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.

  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 movement speed indicating the movement state of the riding part 14, and transmits it to the main control ECU 21. To do. 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.

  Further, 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.

  The main control ECU 21 receives a travel command from the joystick 31 of the input device 30. 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.

  The control ECU 20 functions as an estimation unit that estimates a speed-dependent resistance torque according to the vehicle speed (the rotational angular speed of the drive wheels 12). Moreover, it functions as a posture control means for controlling the posture of the vehicle body according to the estimated speed-dependent resistance torque.

  The speed-dependent resistance is a resistance that increases as the traveling speed increases. In this embodiment, the resistance such as air resistance acting on the vehicle body and viscous friction acting on the rotating shaft of the drive wheel 12 is speed-dependent. Consider as resistance.

  Further, the estimating means estimates a vehicle body air resistance torque that is a torque of an air resistance acting on the vehicle body, a driving wheel friction resistance that is a friction resistance against the rotation of the driving wheel 12, and a counter torque of the air resistance. Further, the posture control means moves the riding portion 14 as the active weight portion to move the position of the center of gravity of the vehicle body.

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

  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 schematic diagram showing the operation of the vehicle at high speed in the first embodiment of the present invention, and FIG. 4 is a flowchart showing the operation of the vehicle traveling and attitude control processing in the first embodiment of the present invention. It is. FIG. 3A shows an example of operation according to the prior art for comparison, and FIG. 3B shows the operation according to the present embodiment.

  In the present embodiment, the driving torque of the driving wheels 12 and the center of gravity position of the vehicle body are corrected according to the traveling speed of the vehicle 10. Specifically, the driving torque is added so as to cancel the speed-dependent resistance torque (viscous resistance torque), and the air resistance torque acting on the vehicle body and the counter-torque against the additional driving torque are reduced by the gravity due to the movement of the center of gravity of the vehicle body As shown in FIG. 3B, the center of gravity of the vehicle 10 is actively corrected by moving the riding portion 14 functioning as the active weight portion in the traveling direction of the vehicle 10 so as to cancel with torque. It is like that. This makes it possible to control the running state and the vehicle body posture with high accuracy even during high-speed running. As a result, it is possible to provide an inverted vehicle 10 with better maneuverability and ride comfort.

  On the other hand, if the driving torque of the driving wheel 12 and the position of the center of gravity of the vehicle body are not corrected as in the conventional vehicle described in the section “Background Art”, the traveling speed increases. The error in controlling the running speed and the vehicle body posture becomes large. That is, in the case of an inverted type vehicle, as shown in FIG. 3A, when the vehicle speed increases, the speed-dependent resistance, that is, the air resistance acting on the vehicle 10 and the viscous friction acting on the rotating shaft of the drive wheel 12 are increased. Such resistance increases, and the influence on running and attitude control becomes stronger.

  Specifically, the vehicle speed may become lower than the target value due to the speed-dependent resistance. In addition, there is a case where the vehicle body tilts backward due to an anti-torque that acts on the vehicle body due to the addition of a drive torque for canceling the air resistance torque and speed-dependent resistance acting on the vehicle body.

  As a result, the maneuverability and ride comfort that are important for mobility are deteriorated. In particular, a general inverted type vehicle has a large projected area with respect to weight and is short in the front-rear direction, and thus is easily affected by air resistance. And the influence extends to the attitude control of the vehicle body. Therefore, the countermeasure is important.

  Therefore, in the present embodiment, the running speed of the vehicle 10 is executed by executing the running and attitude control processing so as to correct the driving torque of the drive wheels 12 and the center of gravity of the vehicle body according to the running speed of the vehicle 10. Even if the vehicle rises, the vehicle 10 can travel stably.

  In the running and posture control process, the control ECU 20 first executes a state quantity acquisition process (step S1), and the driving wheel is driven by each sensor, that is, the driving wheel sensor 51, the vehicle body tilt sensor 41, and the active weight sensor 61. 12 rotation states, vehicle body inclination states, and riding portion 14 movement states are acquired.

  Next, the control ECU 20 executes a target travel state determination process (step S2), and based on the operation amount of the joystick 31, the target value of the acceleration of the vehicle 10 and the target value of the rotational angular velocity of the drive wheels 12 are obtained. decide.

  Next, the control ECU 20 executes a target vehicle body posture determination process (step S3), and based on the target value of the acceleration of the vehicle 10 and the target value of the rotational angular velocity of the drive wheels 12 determined by the target travel state determination process. Thus, the target value of the vehicle body posture, that is, the target value of the vehicle body inclination angle and the active weight portion position is determined.

  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 travel state determined by the target travel state determination process, and the target Based on the target vehicle body posture determined by the vehicle body posture determination process, the outputs of the actuators, that is, the outputs of the drive motor 52 and the active weight motor 62 are 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, inputs, parameters, physical constants, and the like are represented by the following symbols. FIG. 5 shows some of the state quantities and parameters.

State quantity

θ _W : Drive wheel rotation angle [rad]
θ ₁ : Body tilt angle (vertical axis reference) [rad]
λ _S : Active weight part position (vehicle center point reference) [m]

input

τ _W : Driving torque (total of two driving wheels) [Nm]
S _S : Active weight part thrust [N]

Parameters

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 ]
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]
l _S : Active weight part center of gravity distance (from axle) [m]
I _S : Active weight part inertia moment (around the center of gravity) [kgm ² ]

Physical constant

g: Gravity acceleration [m / s ² ]

  Next, the target travel state determination process will be described.

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

  In the target travel 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 determines a target value for vehicle acceleration based on the acquired operation amount of the joystick 31 (step S2-2). For example, a value proportional to the amount of operation of the joystick 31 in the front-rear direction is set as a target value for vehicle acceleration.

Subsequently, the main control ECU 21 calculates the target value of the drive wheel rotation angular velocity from the determined target value of the vehicle acceleration (step S2-3). For example, by integrating the target value of the vehicle acceleration time, a value obtained by dividing the driving wheel contact radius R _W and the target value of the drive wheel rotation angular velocity.

  Next, the target vehicle body posture determination process will be described.

  FIG. 8 is a graph showing changes in the target value of the active weight portion position and the target value of the vehicle body tilt angle in the first embodiment of the present invention, and FIG. 9 shows the target vehicle body posture in the first embodiment of the present invention. It is a flowchart which shows the operation | movement of a determination process.

  In the target body posture determination process, the main control ECU 21 first determines a target value of the active weight portion position and a target value of the vehicle body tilt angle (step S3-1). In this case, based on the target value of the vehicle acceleration determined by the target travel state determination process and the target value of the driving wheel rotation angular velocity, the target value of the active weight portion position is obtained by the following equations (1) and (2). And the target value of the vehicle body inclination angle is determined.

On the other hand, λ _{S, V} ^* is used to balance the vehicle body against the torque caused by the air resistance acting on the vehicle body and the counter-torque of the torque caused by the frictional resistance such as viscous friction acting on the rotating shaft of the drive wheel 12. This is the necessary amount of movement of the active weight portion, that is, the amount of movement that cancels the influence of the speed-dependent resistance. The first term of the numerator of the equation representing λ _{S, V} ^* represents the magnitude of the frictional resistance torque such as viscous friction that acts on the rotating shaft of the drive wheel 12, and the second term acts on the vehicle body. The magnitude of the air resistance torque (strictly speaking, the sum of the torque that the air resistance acting on the vehicle body directly tilts the vehicle body and the anti-torque of the drive torque added to cancel the air resistance).

D _W is the driving wheel frictional resistance coefficient with respect to the driving wheel rotational angular velocity, D ₁ is the vehicle body air resistance coefficient with respect to the driving wheel rotational angular velocity, and h _{1, D} is the vehicle body air resistance center height (the height from the road surface to the center of the air resistance action). And a predetermined constant is given in advance.

On the other hand, θ _{1, V} ^* is used to balance the vehicle body against the torque caused by the air resistance acting on the vehicle body and the counter torque of the torque caused by the frictional resistance such as viscous friction acting on the rotating shaft of the drive wheel 12. This is a necessary vehicle body inclination angle, that is, an inclination angle that cancels the influence of the speed-dependent resistance.

  Subsequently, the main control ECU 21 calculates the remaining target value (step S3-2). That is, the target values of the drive wheel rotation angle, the vehicle body inclination angular velocity, and the active weight portion moving speed are calculated by time differentiation or time integration of each target value.

  Thus, in the present embodiment, not only the inertial force and drive motor reaction torque acting on the vehicle body in accordance with the target value of vehicle acceleration, but also the vehicle body in accordance with the target value of drive wheel rotational angular velocity (vehicle speed). The target value of the vehicle body posture, that is, the target value of the active weight portion position and the target value of the vehicle body tilt angle are determined in consideration of the speed-dependent resistance such as the acting air resistance and the driving motor reaction torque.

  At this time, the center of gravity of the vehicle body is moved so that the torque that acts on the vehicle body to tilt the vehicle body, that is, the vehicle body tilt torque is canceled out by the action of gravity. For example, when the vehicle 10 travels forward, the riding section 14 is moved further forward, or the vehicle body is further tilted forward. Further, when the vehicle 10 travels backward, the riding section 14 is moved further rearward, or the vehicle body is further tilted rearward.

  In the present embodiment, as shown in FIG. 8, first, the riding section 14 is moved without tilting the vehicle body, and when the riding section 14 reaches the active weight movement limit, the tilting of the vehicle body is started. . For this reason, the vehicle body does not tilt forward or backward during fine acceleration / deceleration or low-speed traveling, so that the ride comfort for the occupant 15 is improved and the swing of the field of view is suppressed.

  In the present embodiment, the target value is used as the driving wheel rotation angular velocity for estimating the magnitude of the speed-dependent resistance, but the actually measured value, that is, the actual value is used. Also good. Further, the slip ratio of the drive wheel 12 may be taken into consideration when the air resistance is estimated.

  Further, in the present embodiment, it is assumed that the active weight part movement limit is equal between the front and the rear, but when the front and rear are different, the inclination of the vehicle body is changed according to each limit. The presence or absence may be switched. For example, when the braking performance is set higher than the acceleration performance, it is necessary to set the rear active weight portion movement limit farther than the front.

  Furthermore, in the present embodiment, when acceleration or speed is low, it is handled only by movement of the riding section 14, but part or all of the vehicle body tilt torque may be handled by vehicle body tilt. By tilting the vehicle body, the longitudinal force acting on the occupant 15 can be reduced.

  Furthermore, in this embodiment, the driving wheel frictional resistance torque uses an equation based on a linear model, and the vehicle body air resistance uses an equation based on a model proportional to the square of the speed. An equation based on a non-linear model or a model considering viscous resistance may be used. If the equation is nonlinear, the function may be applied in the form of a map.

  Next, the actuator output determination process will be described.

  FIG. 10 is a flowchart showing the operation of the actuator output determination process in the first embodiment of the present invention.

  In the actuator output determination process, the main control ECU 21 first determines the feedforward output of each actuator (step S4-1). In this case, from each target value, the feedforward output of the drive motor 52 is determined by the following equation (3), and the feedforward output of the active weight motor 62 is determined by the following equation (4).

  In this way, by adding the drive torque so as to cancel the speed-dependent resistance estimated by the dynamic model, the traveling and posture control of the vehicle 10 can be executed with high accuracy, and the same maneuvering feeling is always given to the occupant. 15 can be provided. That is, even during high-speed travel, acceleration / deceleration similar to that during low-speed travel can be performed with respect to a certain steering operation of the joystick 31.

  Thus, in the present embodiment, more accurate control is realized by theoretically giving a feedforward output.

  In the present embodiment, the influence on the position control of the riding section 14 due to the air resistance acting on the riding section 14 is not considered, but this may be considered. For example, as the third term on the right side of Equation (4), a value obtained by multiplying the value obtained by squaring the driving wheel rotational angular velocity by a predetermined coefficient set in advance based on the shape or projected area of the riding section 14 may be added. Good. As a result, more accurate posture control can be realized.

  Further, the feedforward output can be omitted as necessary. In this case, the feedback control indirectly gives a value close to the feedforward output with a steady deviation. Further, the steady deviation can be reduced by applying an integral gain.

  Subsequently, the main control ECU 21 determines the feedback output of each actuator (step S4-2). In this case, the feedback output of the drive motor 52 is determined by the following equation (5) from the deviation between each target value and the actual state quantity, and the feedback output of the active weight unit motor 62 by the following equation (6). To decide.

Note that nonlinear feedback control such as sliding mode control can also be introduced. As simpler control, some of the feedback gains excluding K _W2 , K _W3, and K _S5 may be set to zero. Further, an integral gain may be introduced in order to eliminate the steady deviation.

  Finally, the main control ECU 21 gives a command value to each element control system (step S4-3). In this case, the main control ECU 21 transmits the sum of the feedforward output and the feedback output determined as described above to the drive wheel control ECU 22 and the active weight part control ECU 23 as the drive torque command value and the active weight part thrust command value. .

  Thus, in the present embodiment, the driving torque of the driving wheels 12 and the center of gravity position of the vehicle body are corrected according to the traveling speed of the vehicle 10. In other words, the driving torque is added so as to cancel the speed-dependent resistance, and the riding portion 14 is set so as to cancel the air resistance torque acting on the vehicle body and the counter-torque against the added amount of the driving torque by the gravity torque accompanying the movement of the center of gravity of the vehicle body. Move back and forth. As a result, even during high-speed traveling, the traveling state and the vehicle body posture can be controlled with high accuracy, and maneuverability and riding comfort can be further improved.

  In the present embodiment, the viscous friction acting on the drive wheel 12 and the air resistance acting on the vehicle body are taken into consideration as the speed-dependent resistance, but other actions may be taken into consideration. For example, by taking into account the component that increases with the speed of the rolling friction resistance of the drive wheel 12 or the air resistance acting on the drive wheel 12 in the same manner as the viscous friction acting on the drive wheel 12, higher accuracy can be achieved. Control can be realized.

  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. 11 is a block diagram showing the configuration of a vehicle control system according to the second embodiment of the present invention, and FIG. 12 is a schematic diagram showing the operation of the vehicle during high speed travel according to the second embodiment of the present invention. . FIG. 12A shows an operation example according to the prior art for comparison, and FIG. 12B shows an operation according to the present embodiment.

  In the first embodiment, the riding part 14 is attached so as to be able to translate relative to the main body part 11 in the front-rear direction of the vehicle 10 and functions as an active weight part. In this case, a moving mechanism including the active weight motor 62 is disposed, and thereby the riding section 14 is translated. Therefore, the structure and the control system may be complicated, costly, and increased in weight. Naturally, it is impossible to apply to an inverted vehicle that does not have a moving mechanism for moving the riding section 14.

  Therefore, in the present embodiment, a moving mechanism for moving the riding section 14 is omitted. As shown in FIG. 11, the active weight part control system 60 is omitted from the control system, and the active weight part control ECU 23, the active weight part sensor 61, and the active weight part motor 62 are omitted. Since the configuration of other points is the same as that of the first embodiment, description thereof is omitted.

  In the present embodiment, the driving torque of the driving wheels 12 and the inclination angle of the vehicle body are corrected according to the traveling speed of the vehicle 10. Specifically, the driving torque is added so as to cancel the speed-dependent resistance torque (viscous resistance torque), and the viscous resistance torque acting on the vehicle body and the counter-torque against the additional driving torque are reduced by the gravity due to the movement of the center of gravity of the vehicle body. As shown in FIG. 12B, the position of the center of gravity of the vehicle 10 is actively corrected by tilting the vehicle body in the traveling direction of the vehicle 10 so as to cancel the torque. This makes it possible to control the running state and the vehicle body posture with high accuracy even during high-speed running. As a result, it is possible to provide an inexpensive inverted vehicle 10 that has good maneuverability and ride comfort even when traveling at high speed.

  On the other hand, if the driving torque of the driving wheel 12 and the inclination angle of the vehicle body are not corrected according to the traveling speed as in the conventional vehicle described in the section “Background Art”, the traveling speed increases. The error in controlling the running speed and the vehicle body posture becomes large. That is, in the case of an inverted type vehicle, as shown in FIG. 12A, when the vehicle speed increases, the speed-dependent resistance, that is, the air resistance acting on the vehicle 10 or the viscous friction acting on the rotating shaft of the drive wheel 12 is increased. Such resistance increases, and the influence on running and attitude control becomes stronger.

  Specifically, the vehicle speed may become lower than the target value due to the speed-dependent resistance. In addition, there is a case where the vehicle body tilts backward due to an anti-torque that acts on the vehicle body due to the addition of a driving torque for canceling the air resistance torque and the speed-dependent resistance acting on the vehicle body. As a result, the maneuverability and ride comfort that are important for mobility are deteriorated.

  Therefore, in the present embodiment, the running speed of the vehicle 10 is executed by executing the running and attitude control processing so as to correct the driving torque of the drive wheels 12 and the inclination angle of the vehicle body according to the running speed of the vehicle 10. Even if the vehicle rises, the vehicle 10 can stably stop and travel.

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

FIG. 13 is a flowchart showing the operation of the state quantity acquisition process in the second embodiment of the present invention.

  Next, the target vehicle body posture determination process will be described.

  FIG. 14 is a flowchart showing the operation of target body posture determination processing in the second embodiment of the present invention.

  In the determination process of the target vehicle body posture, the main control ECU 21 first determines a target value of the vehicle body inclination angle (step S3-11). In this case, the target value of the vehicle body tilt angle is determined by the following equation (7) based on the target value of the vehicle acceleration and the target value of the drive wheel rotational angular velocity determined by the target travel state determination process.

On the other hand, θ _{1, V} ^* is necessary to balance the vehicle body against the torque caused by the air resistance acting on the vehicle body and the counter-torque of the torque caused by the frictional resistance such as viscous friction acting on the rotating shaft of the drive wheel 12. The vehicle body inclination angle, that is, the inclination angle that cancels the influence of the speed-dependent resistance.

  Subsequently, the main control ECU 21 calculates the remaining target value (step S3-12). That is, the target values of the drive wheel rotation angle and the vehicle body inclination angular velocity are calculated by time differentiation or time integration of each target value.

  Thus, in the present embodiment, not only the inertial force and drive motor reaction torque acting on the vehicle body in accordance with the target value of vehicle acceleration, but also the vehicle body in accordance with the target value of drive wheel rotational angular velocity (vehicle speed). The target value of the vehicle body inclination angle is determined in consideration of the speed-dependent resistance such as the acting air resistance and the driving motor reaction torque.

  At this time, the center of gravity of the vehicle body is moved so that the torque that acts on the vehicle body to tilt the vehicle body, that is, the vehicle body tilt torque is canceled out by the action of gravity. For example, when the vehicle 10 travels forward, the vehicle body is tilted further forward. Further, when the vehicle 10 travels backward, the vehicle body is tilted further rearward.

  In the present embodiment, the driving wheel frictional resistance torque uses an equation based on a linear model, and the vehicle body air resistance uses an equation based on a model proportional to the square of the speed. An equation based on a non-linear model or a model considering viscous resistance may be used. If the equation is nonlinear, the function may be applied in the form of a map.

  Next, the actuator output determination process will be described.

  FIG. 15 is a flowchart showing the operation of the actuator output determination process in the second embodiment of the present invention.

  In the actuator output determination process, the main control ECU 21 first determines the feedforward output of the actuator (step S4-11). In this case, the feedforward output of the drive motor 52 is determined from each target value according to the equation (3) described in the first embodiment.

  As represented by the above formula (3), the driving and attitude control of the vehicle 10 can be executed with high accuracy by adding the driving torque so as to cancel the speed-dependent resistance estimated by the dynamic model. Therefore, it is possible to always provide the passenger 15 with the same steering feeling. That is, even during high-speed travel, acceleration / deceleration similar to that during low-speed travel can be performed with respect to a certain operation of the joystick 31.

  Subsequently, the main control ECU 21 determines the feedback output of the actuator (step S4-12). In this case, the feedback output of the drive motor 52 is determined by the following equation (8) from the deviation between each target value and the actual state quantity.

Note that nonlinear feedback control such as sliding mode control can also be introduced. As a simpler control, some of the feedback gains excluding K _W2 and K _W3 may be set to zero. Further, an integral gain may be introduced in order to eliminate the steady deviation.

  Finally, the main control ECU 21 gives a command value to the element control system (step S4-13). In this case, the main control ECU 21 transmits the sum of the feedforward output and the feedback output determined as described above to the drive wheel control ECU 22 as a drive torque command value.

  Thus, in the present embodiment, the driving torque of the driving wheels 12 and the center of gravity position of the vehicle body are corrected according to the traveling speed of the vehicle 10. In other words, the drive torque is added to cancel the speed-dependent resistance, and the vehicle body is moved forward so that the air resistance torque acting on the vehicle body and the counter torque against the added amount of drive torque are canceled by the gravity torque accompanying the movement of the center of gravity of the vehicle body Tilt. Therefore, the present invention can be applied to an inverted vehicle that does not have a moving mechanism for the riding section 14. Further, the structure and the control system can be simplified, and an inexpensive and light inverted vehicle can be realized.

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

  In the present embodiment, the airspeed is measured, and the vehicle 10 is controlled based on the measured value.

  If the air resistance is estimated based on the driving wheel rotation angular velocity, a large error may occur in the estimated value of the air resistance when the driving wheel 12 idles. In general, when the vehicle speed estimated from the rotational speed of the drive wheels 12 is used, the air resistance is overestimated. This is because the air resistance is proportional to the square of the speed, so that the error becomes remarkably large. Further, since the driving torque is increased with respect to an erroneous estimated value of air resistance, there is a possibility that the idling state of the driving wheels 12 is further deteriorated. Furthermore, since the center of gravity of the vehicle body is moved so as to balance with an erroneous estimated value of air resistance, the vehicle body may be greatly inclined. The same problem occurs when the drive wheel 12 is locked and slips on the road surface.

  Further, when the outside air wind becomes strong, an error in controlling the traveling speed and the vehicle body posture becomes large. This is because the large air resistance caused by the strong wind affects the running and attitude control of the vehicle 10. As a result, the maneuverability and the ride comfort are deteriorated as mobility. In general, an inverted type vehicle has a low traveling speed, and therefore the influence of outside air wind is relatively large.

  Therefore, in the present embodiment, the drive torque of the drive wheels 12 and the position of the riding section 14 are corrected according to the rotational speed of the drive wheels 12 and the airspeed of the vehicle 10. Specifically, the viscous friction acting on the driving wheel 12 is estimated based on the rotational speed of the driving wheel, and the air resistance acting on the vehicle body is estimated based on the air speed measured by the airspeed meter.

  As a result, for example, even when the drive wheel 12 is idling, it is possible to provide a highly accurate control of the traveling state and the vehicle body posture, and to provide the inverted vehicle 10 with good maneuverability and ride comfort. Similarly, even when a strong wind is generated, it is possible to provide the inverted vehicle 10 that realizes highly accurate control of the running state and the vehicle body posture, and has good maneuverability and ride comfort.

  Therefore, the vehicle 10 has an air speed sensor 71 as air speed measuring means as shown in FIG. The airspeed sensor 71 is, for example, a measuring device using a Pitot tube that measures dynamic pressure, but may be any type of sensor as long as it can measure airspeed. .

  The vehicle 10 also has an air speed measurement system 70 including an air speed sensor 71. The air speed sensor 71 measures the air speed, which is the speed of the vehicle 10 with respect to the outside air, and transmits it to the main control ECU 21.

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

FIG. 17 is a flowchart showing the operation of the state quantity acquisition process in the third embodiment of the invention.

  Subsequently, the main control ECU 21 acquires the airspeed (step S1-23). In this case, the air speed measured by the air speed sensor 71 is acquired.

  Next, the target vehicle body posture determination process will be described.

  FIG. 18 is a flowchart showing the operation of target body posture determination processing in the third embodiment of the present invention.

  In the target body posture determination process, the main control ECU 21 first determines the target value of the active weight portion position and the target value of the vehicle body tilt angle (step S3-21). In this case, the first embodiment is based on the target value of the vehicle acceleration determined by the target travel state determination process, the target value of the driving wheel rotation angular velocity, and the airspeed measured by the airspeed sensor 71. The target value of the active weight portion position and the target value of the vehicle body inclination angle are determined by the equations (1) and (2) described in the above.

  Subsequently, the main control ECU 21 calculates the remaining target value (step S3-22). That is, the target values of the drive wheel rotation angle, the vehicle body inclination angular velocity, and the active weight portion moving speed are calculated by time differentiation or time integration of each target value.

  Thus, in the present embodiment, not only the inertial force and drive motor reaction torque acting on the vehicle body in accordance with the target value of vehicle acceleration, but also the vehicle body in accordance with the target value of drive wheel rotational angular velocity (vehicle speed). The target value of the vehicle body posture, that is, the target value of the active weight portion position and the target value of the vehicle body tilt angle are determined in consideration of the speed-dependent resistance such as the acting air resistance and the driving motor reaction torque.

  At this time, the center of gravity of the vehicle body is moved so that the torque that acts on the vehicle body to tilt the vehicle body, that is, the vehicle body tilt torque is canceled out by the action of gravity. For example, when the vehicle 10 travels forward or when a head wind from the front exists, the riding section 14 is moved further forward, or the vehicle body is further tilted forward. Further, when the vehicle 10 travels backward or when there is a tailwind from the rear, the riding section 14 is moved further rearward, or the vehicle body is further tilted rearward.

  In the present embodiment, as shown in FIG. 8 described in the first embodiment, first, the riding section 14 is moved without tilting the vehicle body, and the riding section 14 has an active weight section movement limit. When it reaches, the body tilt starts. For this reason, the vehicle body does not tilt forward and backward when traveling at low speeds or weak outside air, so that the riding comfort for the occupant 15 is improved and the swing of the field of view is suppressed.

  In the present embodiment, the target value is used as the rotational angular velocity of the driving wheel for estimating the viscous friction of the driving wheel 12, but the actually measured value, that is, the actual value is used. Also good.

  Further, in the present embodiment, it is assumed that the active weight part movement limit is equal between the front and the rear, but when the front and rear are different, the inclination of the vehicle body is changed according to each limit. The presence or absence may be switched. For example, when the braking performance is set higher than the acceleration performance, it is necessary to set the rear active weight portion movement limit farther than the front.

  Further, in the present embodiment, when the acceleration or speed of the vehicle 10 is low or the outside air wind is weak, only the movement of the riding section 14 is used. You may make it correspond by inclination. By tilting the vehicle body, the longitudinal force acting on the occupant 15 can be reduced.

  Furthermore, in this embodiment, the driving wheel frictional resistance torque uses an equation based on a linear model, and the vehicle body air resistance uses an equation based on a model proportional to the square of the speed. An equation based on a non-linear model or a model considering viscous resistance may be used. If the equation is nonlinear, the function may be applied in the form of a map.

  Next, the actuator output determination process will be described.

  FIG. 19 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, the main control ECU 21 first determines the feedforward output of each actuator (step S4-21). In this case, the feedforward output of the drive motor 52 is determined from each target value and the airspeed by the following equation (9), and active by the equation (4) described in the first embodiment. The feedforward output of the weight part motor 62 is determined.

  In this way, by adding the drive torque so as to cancel the speed-dependent resistance torque estimated by the dynamic model, it is possible to execute the traveling and posture control of the vehicle 10 with high accuracy, and to always have the same control feeling. It can be provided to the occupant 15. That is, even during high-speed traveling or when strong outdoor air is present, acceleration / deceleration similar to that during low-speed traveling can be performed with respect to a certain steering operation of the joystick 31.

  Subsequently, the main control ECU 21 determines the feedback output of each actuator (step S4-22). In this case, the feedback output of the drive motor 52 is determined from the deviation between each target value and the actual state quantity by the equation (5) described in the first embodiment, and the first embodiment The feedback output of the active weight section motor 62 is determined by the equation (6) described in the embodiment.

Note that nonlinear feedback control such as sliding mode control can also be introduced. As simpler control, some of the feedback gains excluding K _W2 , K _W3, and K _S5 may be set to zero. Further, an integral gain may be introduced in order to eliminate the steady deviation.

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

  Thus, in the present embodiment, the drive torque of the drive wheel 12 and the position of the riding section 14 are corrected according to the rotational speed of the drive wheel 12 and the airspeed of the vehicle 10. That is, the frictional resistance torque acting on the driving wheel 12 is estimated based on the driving wheel rotational angular velocity, and the air resistance acting on the vehicle body is estimated based on the airspeed measured by the airspeed meter.

  As a result, even when the drive wheel 12 is idling or slipping, the running state and the vehicle body posture can be controlled with high accuracy, and therefore, the inverted vehicle 10 having good maneuverability and ride comfort can be provided. it can. Further, even when the outside air wind is strong, similarly, the traveling state and the vehicle body posture can be controlled with high accuracy, so that the inverted vehicle 10 with good maneuverability and ride comfort can be provided.

  In the present embodiment, the example in which the air resistance is estimated based on the air speed acquired from the air speed sensor 71 has been described. However, as the air speed sensor 71, a dynamic pressure measurement type sensor such as a Pitot tube is used. May be used to directly obtain the dynamic pressure value and estimate the air resistance. Thereby, the influence by the density change of air | atmosphere can be considered correctly.

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

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 the schematic which shows the operation | movement at the time of high speed driving | running | working of the vehicle in the 1st Embodiment of this invention. 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 driving state in the 1st Embodiment of this invention. It is a graph which shows the change of the target value of the active weight part position in the 1st Embodiment of this invention, and the target value of a vehicle body tilt angle. It is a flowchart which shows the operation | movement of the determination process of the target vehicle body attitude | position 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 block diagram which shows the structure of the control system of the vehicle in the 2nd Embodiment of this invention. It is the schematic which shows the operation | movement at the time of high speed driving | running | working of the vehicle in the 2nd Embodiment of this invention. It is a flowchart which shows the operation | movement of the acquisition process of the state quantity in the 2nd Embodiment of this invention. It is a flowchart which shows the operation | movement of the determination process of the target vehicle body attitude | position 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 target vehicle body attitude | position 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.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle 12 Drive wheel 14 Boarding part 20 Control ECU
71 Airspeed sensor

Claims (5)

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
Estimating means for estimating a speed-dependent resistance torque that is a resistance torque acting on the driving wheel and / or the vehicle body as the vehicle speed increases;
A vehicle comprising: attitude control means for moving the center of gravity of the vehicle body in the traveling direction of the drive wheel relative to the drive wheel in accordance with the speed-dependent resistance torque estimated by the estimation means.   The vehicle according to claim 1, wherein the vehicle control device moves the center of gravity of the vehicle body by tilting the vehicle body. An active weight portion movably attached to the vehicle body;
The vehicle according to claim 1, wherein the vehicle control device moves the center of gravity of the vehicle body by moving the active weight portion.   The estimation means estimates a vehicle body air resistance torque that is a torque of an air resistance acting on the vehicle body and / or a driving wheel friction resistance that is a friction resistance against rotation of the driving wheel and / or a counter torque of the air resistance. The vehicle according to any one of claims 1 to 3. 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 includes an airspeed measuring means for measuring an airspeed,
A vehicle characterized in that the center of gravity of the vehicle body is moved relative to the drive wheel in the direction of airspeed by an amount corresponding to the magnitude of airspeed measured by the airspeed measuring means.

Images