JP2010202117A - Vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inversion type vehicle having a prohibition means which calculates the probability of inclination of a vehicle body in the getting-off direction, predicts the inclining direction of the vehicle body according to the value, and prohibits the execution of an overturn preventive device, and is capable of reliably operating the overturn preventive device only when it is necessary according to the correct determination based on the prediction of the inclining direction of the vehicle body by setting the execution of the overturn preventive device to be in a prohibitive state in advance if predicting the inclination of the vehicle body in the getting-off direction, preventing any excessive time and cost by a user according to any unnecessary operation of the overturn preventive device, and ensuring the sufficient safety only by a vehicle body fixed type single-side stopper. <P>SOLUTION: A vehicle control device includes an inclining direction predicting means for predicting the inclining direction of a vehicle body when stopping the control of the posture of the vehicle body, and a prohibition means for prohibiting the execution of an overturn preventive device based on the inclining direction of the vehicle body predicted by the inclining direction predicting means. <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 occupant, 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 moved by performing the inversion control while detecting the balance of the vehicle body and the state of operation by the sensor. Also, when the occupant gets off the vehicle or shuts off the vehicle power, the inversion control is stopped and the stopper is operated at the same time, and the posture of the vehicle body is maintained by grounding the stopper. The stopper is prevented from becoming a hindrance to travel by being separated from the road surface.

JP 2004-291799 A

  However, in the conventional vehicle, it is necessary to attach movable stoppers to the front and rear of the vehicle, which complicates the configuration and hinders weight reduction and cost reduction of the vehicle.

  Therefore, it is conceivable to attach a fixed stopper to one side of the vehicle. When the occupant gets off, the vehicle body is tilted in a direction in which the occupant can easily get off, and the stopper fixed to the vehicle body is grounded to the ground. In addition, a fall prevention device is attached in case the vehicle body tilts in the opposite direction during an emergency stop. Since the fall prevention device operates only in an emergency, a simple system is desirable. For example, an airbag is used as the fall prevention device.

  Here, it is desirable not to operate the fall prevention device unless the vehicle body is inclined in the reverse direction. For example, in the case of an air bag, it needs to be replaced after being activated, which requires time and money for the occupant or vehicle manager. Therefore, it is desirable to operate the fall prevention device only when the vehicle body is inclined in the reverse direction.

  Moreover, depending on the case, there is a possibility that the fall prevention device cannot be operated properly. For example, when the fall prevention device is operated after confirming the inclination direction of the vehicle body, a part of the vehicle body may come into contact with the road surface before the fall prevention device functions. Further, when the inversion control is stopped urgently as a result of a failure of an ECU (Electronic Control Unit) that performs arithmetic processing related to a failure or control of a sensor that measures the tilt state of the vehicle body, or a power supply to the ECU, It is impossible to confirm the direction of the inclination.

  The present invention solves the problems of the conventional vehicle, calculates the probability of leaning in the direction of getting off the vehicle body, predicts the leaning direction of the vehicle body based on the calculated value, and executes the overturn preventing means for operating the overturn preventing device. Providing prohibition means to prohibit, and when the vehicle body tilt in the direction of getting off is predicted, the execution of the fall prevention means is prohibited in advance, so that only when necessary by accurate judgment based on the prediction of the vehicle body tilt direction Since the fall prevention device can be operated reliably, unnecessary operation of the fall prevention device does not require the user to spend extra time and money, and sufficient safety is ensured with only the vehicle-fixed one-side stopper. As a result, an object is to provide a simple, small, lightweight, inexpensive, safe and convenient vehicle.

  For this purpose, in the vehicle of the present invention, the drive wheel rotatably attached to the vehicle body, the overturn prevention device for preventing the vehicle body from overturning, and the drive torque applied to the drive wheel to control the posture of the vehicle body A vehicle control device for controlling the vehicle body, the vehicle control device predicting a direction in which the vehicle body tilts when the control of the posture of the vehicle body is stopped, and a vehicle body predicted by the tilt direction prediction device. And prohibiting means for prohibiting the execution of the fall prevention device based on the direction in which the tilting device tilts.

  In another vehicle of the present invention, the prohibiting unit further executes the fall prevention device based on a direction in which the vehicle body tilts predicted by the tilt direction prediction unit immediately before stopping control of the posture of the vehicle body. Is prohibited.

  In still another vehicle of the present invention, the vehicle further includes posture restriction means for restricting the posture angle of the vehicle body, and the vehicle control device includes the direction in which the vehicle body leans predicted by the lean direction prediction means and the posture restriction. When the direction in which the means functions coincides, the prohibiting means prohibits the execution of the fall prevention device.

  In still another vehicle of the present invention, the tilt direction prediction means predicts the direction in which the vehicle body tilts according to the tilt state of the vehicle body and / or the rotation state of the drive wheels.

  In still another vehicle of the present invention, the tilt direction prediction unit further includes a center-of-gravity shift amount acquisition unit that acquires a center-of-gravity shift amount of the vehicle body, and the center-of-gravity shift of the vehicle body acquired by the center-of-gravity shift acquisition unit. The direction in which the vehicle body tilts is predicted by the amount.

  In yet another vehicle of the present invention, the center-of-gravity deviation acquisition means further includes the center of gravity of the vehicle body based on the tilt state of the vehicle body and / or the rotation state of the drive wheel and / or the time history of the drive torque. Estimate the amount of deviation.

  In still another vehicle of the present invention, the leaning direction predicting means predicts deceleration state and deceleration time of the vehicle after stopping the control of the posture of the vehicle body based on the traveling speed of the vehicle. And a direction in which the vehicle body tilts is predicted based on the deceleration predicted by the deceleration state prediction means and the deceleration time.

  In still another vehicle of the present invention, the tilt direction prediction means calculates a probability that the vehicle body tilts in a specific direction when the control of the posture of the vehicle body is stopped, and the calculated probability is equal to or greater than a predetermined threshold value. At some point, the vehicle body is predicted to tilt in a specific direction.

  In still another vehicle of the present invention, the vehicle control device further cuts off the power supply of the vehicle when stopping the control of the posture of the vehicle body.

  In yet another vehicle of the present invention, the prohibiting means further includes a prohibition signal for prohibiting execution of the tipping prevention device when the tilt direction predicting means predicts that the vehicle body tilts in a specific direction. The fall prevention device does not execute when the prohibition signal is received immediately before the power source of the vehicle body is shut off, and receives the prohibition signal immediately before the power source of the vehicle body is shut off. If not, execute it.

  In yet another vehicle of the present invention, the fall prevention device operates an airbag that is interposed between the vehicle body and a road surface and limits an inclination angle of the vehicle body within a predetermined threshold.

  In yet another vehicle of the present invention, the overturn prevention device operates a movable mass that moves the center of gravity of the vehicle body to the opposite side in the direction of overturning.

  According to the configuration of claim 1, in order to predict the inclination direction of the vehicle body and to reliably perform the operation of the anti-tip device only when it is predicted to be necessary, execution of unnecessary anti-tip means, and The labor and cost required for the post-processing can be eliminated.

  According to the configuration of the second aspect, when the posture control is stopped and the tilt direction is predicted before the vehicle body actually tilts, and the fall prevention means is executed as necessary, the execution of the fall prevention device is delayed. Alternatively, even when it is difficult to acquire the vehicle tilt state due to a sensor failure or the like, the fall prevention means can function reliably when necessary. Further, by using the latest prediction result before stopping the posture control, the fall prevention device can be executed or prohibited based on the more reliable prediction.

  According to the configuration of the third aspect, for example, a stopper for limiting the vehicle body inclination angle is provided only on one side of the vehicle body, and the vehicle is normally stopped by inclining the vehicle body to the stopper side, and falls only in an emergency in which the vehicle is inclined to the opposite side. A vehicle that executes the prevention device can be realized, and a small and safe inverted vehicle can be provided.

  According to the configuration of the fourth aspect, the inclination direction of the vehicle body is predicted with high accuracy by predicting the inclination direction of the vehicle body based on the dynamic model relating to the vehicle body inclination in consideration of the inclination state of the vehicle body and the rotation state of the drive wheels. can do.

  According to the configuration of the fifth aspect, the inclination direction of the vehicle body can be predicted with higher accuracy by taking into account the shift of the center of gravity of the vehicle body that changes depending on the situation of the occupant and the load.

  According to the configuration of the sixth aspect, by acquiring the center-of-gravity shift of the vehicle body by estimation, a sensor for measuring the center-of-gravity shift is unnecessary, and low-cost and high-precision tilt direction prediction can be realized.

  According to the configuration of the seventh aspect, it is possible to predict the inclination direction of the vehicle body with higher accuracy by predicting the deceleration process of the vehicle after stopping the attitude control and considering the inertial force acting on the vehicle body in accordance with the deceleration. .

  According to the structure of Claim 8, it becomes possible to determine a prediction result quantitatively by determining the prediction result of an inclination direction by the numerical value of a probability, and can implement a fall prevention apparatus more appropriately.

  According to the configuration of claim 9, by unifying the various inversion control stop conditions to the strictest condition of power shut-off, the tipping prevention device can be surely installed as needed for any conditions during posture control stop. Can be executed. In addition, the control design is facilitated by unifying to one condition.

  According to the configuration of the tenth aspect, by using the information on the power shutdown as the condition for executing the fall prevention means, the fall prevention device can be reliably executed as necessary even when the power is shut off.

1 is a schematic diagram showing a configuration of a vehicle in a first embodiment of the present invention. It is a block diagram which shows the structure of the vehicle system in the 1st Embodiment of this invention. It is a block diagram which shows the structure of the vehicle body fall prevention system of the vehicle in the 1st Embodiment of this invention. It is a figure which shows the input / output signal of the vehicle body fall prevention system of the vehicle in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement of the vehicle control process in the 1st Embodiment of this invention. It is a figure which shows the relationship between the substantial vehicle body inclination angle and the forward inclination probability in the 1st Embodiment of this invention. It is a flowchart which shows the operation | movement of the inclination direction prediction process in the 1st Embodiment of this invention. It is the schematic which shows the structure of the vehicle 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 2nd Embodiment of this invention. It is the schematic which shows the structure of the vehicle in the 3rd Embodiment of this invention. It is the schematic which shows the structure of the vehicle in the 4th Embodiment of this invention.

  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 the vehicle in the first embodiment of the present invention, FIG. 2 is a block diagram showing the configuration of the vehicle system in the first embodiment of the present invention, and FIG. FIG. 4 is a block diagram illustrating a configuration of a vehicle body fall prevention system according to the first embodiment, and FIG. 4 is a diagram illustrating input / output signals of the vehicle body fall prevention system according to the first embodiment of the present invention. In FIG. 4, (a) represents the case where the fall prevention device does not operate, and (b) represents the case where the fall prevention device operates.

  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 can move forward in the right direction and move backward in the left 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, a description will be given 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 section 14 is the same as a seat used for automobiles such as passenger cars and buses, and includes a footrest section, a seat surface section, a backrest section, and a headrest.

  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.

  The input device 30 includes a control switch 32 as a stop request acquisition unit. When the occupant 15 desires to start traveling or get off, the control changeover switch 32 is operated to input an inversion control execution or stop command. Here, as long as it is a device that can be operated by the occupant 15 to input execution or stop of the inverted control, another device such as a push button, a touch panel, an operation lever, or a voice recognition system is used instead of the control changeover switch 32. Such a device can also be used as a stop request acquisition means. Moreover, these may be a device that commands only one of execution or stop.

  When the vehicle 10 is steered by remote control, a receiving device that receives a travel command from the controller in a wired or wireless manner is used as the target travel state acquisition device instead of the joystick 31 and the control changeover switch 32. be able to. In addition, when the vehicle 10 automatically travels according to predetermined travel command data, data that reads travel command data stored in a storage medium such as a semiconductor memory or a hard disk instead of the joystick 31 and the control changeover switch 32. The reading device can be used as a target running state acquisition device.

  Further, a stopper 16 as a fixed posture limiting means is attached to the footrest part of the riding part 14. The stopper 16 is preferably formed integrally with the footrest. When the inversion control is stopped, the posture angle of the vehicle body is limited by at least a part of the stopper 16, for example, the front end portion coming into contact with the road surface, and the vehicle body is prevented from being inclined more than a predetermined angle.

  The direction in which the vehicle body tilts when getting off, that is, the direction in which the vehicle body is inclined when the vehicle 10 is stopped and the occupant 15 gets off, may be either forward or backward. The vehicle 10 will be described assuming that the dismounting direction is forward. When the inversion control is stopped when the vehicle gets off, the vehicle body tilts forward and the front end of the stopper 16 contacts the road surface, so that the posture of the vehicle body is stabilized and the occupant 15 can get off safely.

  On the other hand, a fall prevention device 17 for preventing the vehicle body from falling in the direction opposite to the dismounting direction is attached to the back surface of the riding section 14. The overturn prevention device 17 may be any type of device as long as it is a device that automatically operates at the time of emergency inversion control stop and prevents the vehicle body from overturning, but in the present embodiment, an airbag is used. It will be described as being an apparatus. When the airbag device is activated, high-pressure gas generated by a gas generator (inflator) is injected into the bag and the bag rapidly inflates and contacts the road surface, preventing the vehicle body from falling backward. Is done.

  As shown in FIG. 2, the vehicle system has a control ECU 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 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 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.

  Further, the main control ECU 21 controls the vehicle body fall prevention system 60 as a fall prevention means including the operation prohibition switch 61 and the fall prevention device 17. At the time of emergency stop of the vehicle 10, a signal for operating the fall prevention device 17 is automatically transmitted from the main control ECU 21 to the vehicle body fall prevention system 60, and at this time, only when the operation inhibition switch 61 has not received the inhibition signal. The fall prevention device 17 is activated.

  Specifically, as shown in FIG. 3, the operation prohibiting switch 61 includes a falling trigger 62 that outputs a signal for a predetermined time when the input signal falls (when it changes from ON to OFF), An electronic circuit that includes a delay element 63 that delays an input signal by a predetermined time T, and a logical product 64 that outputs a signal only when both signals are input (one of which is negative), and executes a logical operation process. is there. Then, when the power supply signal corresponding to the power-on state of the vehicle system and the prohibition signal from the main control ECU 21 are input, the operation prohibiting switch 61 sends an operation signal as shown in FIG. Output.

  The falling trigger 62 outputs a falling trigger signal of the power signal as a signal when the power signal corresponding to the power-on state of the vehicle system changes to the OFF state, that is, when the power is shut off. This prevents the fall prevention device 17 from operating at times other than when the power is shut off (emergency stop). The delay element 63 delays the prohibition signal from the main control ECU 21 by a predetermined time. That is, whether to prohibit the operation is determined according to the state of the prohibition signal only a predetermined time before the power is shut off. As a result, even when the main control ECU 21 is turned off together with the power supply of the vehicle system, even if the main control ECU 21 cannot transmit the prohibition signal, the operation of the fall prevention device 17 can be reliably prohibited. . Further, the logical product 64 receives the falling trigger signal of the power supply signal and does not receive the prohibition signal delayed by the predetermined time T, that is, the prohibition signal immediately before the power shutoff is OFF. The operation signal of the fall prevention device 17 is output. Thereby, it can be set beforehand whether the fall prevention device 17 is operated by a prohibition signal.

  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.

  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.

  From the viewpoint of function, the control ECU 20 acquires a tilt direction predicting unit that predicts the direction in which the vehicle body tilts when the inversion control is stopped, a prohibiting unit that prohibits execution of the overturn preventing unit, and a center-of-gravity shift amount of the vehicle body. A center-of-gravity deviation amount acquisition unit and a deceleration state prediction unit that predicts the deceleration process of the vehicle after stopping the inversion control are provided.

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

  FIG. 5 is a flowchart showing the operation of the vehicle control process in the first embodiment of the present invention.

  In the vehicle control process, the control ECU 20 first performs system abnormality determination to determine whether or not an abnormality has occurred (step S1). In this case, for example, the state where the inversion control cannot be maintained due to the interruption of the power supply due to the abnormality of the battery, the failure of each sensor, the failure of each actuator, the abnormality of each ECU, the communication abnormality between the elements, etc. It is determined whether or not.

  If it is determined that no abnormality has occurred, the control ECU 20 determines whether to get off the vehicle and determines whether or not it is desired to get off (step S2). In this case, an execution / stop command signal input from the control switch 32 of the input device 30 is acquired, and it is determined whether or not the occupant 15 desires to get off. Specifically, it is determined that the occupant 15 does not want to get off in the case of an execution command, and that the occupant 15 wants to get off in the case of a stop command.

  If it is determined that the user does not want to get off, the control ECU 20 executes the inversion control (step S3), and realizes the traveling state commanded by the occupant 15 while maintaining the inverted posture of the vehicle body. Note that the contents of the inversion control are the same as the inversion control in a normal inverted type vehicle, and thus the description thereof is omitted.

  Subsequently, the control ECU 20 executes a tilt direction prediction process (step S4), and determines a probability that the vehicle body tilts forward as a prediction of the vehicle body tilt direction when the inversion control is stopped.

  Subsequently, the control ECU 20 performs a tilt direction determination based on the result of the tilt direction prediction process, and determines whether or not it is a forward tilt (step S5). In this case, whether or not the vehicle body is surely inclined forward is determined by the forward inclination probability. Specifically, it is determined that the vehicle is inclined forward when the forward inclination probability is equal to or greater than a predetermined threshold.

  And when it is not forward inclination, control ECU20 performs permission instruction | command (step S6), and complete | finishes a process. Specifically, by stopping the prohibition signal transmitted from the main control ECU 21 to the operation prohibition switch 61, the operation of the vehicle body fall prevention system 60 at the time of emergency stop is permitted.

  Further, when the vehicle is inclined forward, the control ECU 20 issues a prohibition command (step S7) and ends the process. More specifically, the prohibition signal is transmitted from the main control ECU 21 to the operation prohibiting switch 61 to prohibit the operation of the vehicle body fall prevention system 60 during an emergency stop.

  On the other hand, when it is determined in the system abnormality determination that an abnormality has occurred, the control ECU 20 performs power shutdown, that is, emergency stop (step S8), shuts off the vehicle system power, and ends the vehicle control process. As described above, the falling trigger 62 outputs the falling trigger signal of the power signal when the power is shut off. The logical product 64 receives the falling trigger signal of the power supply signal and outputs an operation signal of the overturn prevention device 17 when the prohibition signal immediately before the power cut-off is OFF. Then, since the fall prevention device 17 operates, the fall of the vehicle body to the rear is prevented. In addition, when the prohibition signal immediately before the power shut-off is ON, the operation signal of the fall prevention device 17 is not output, so the fall prevention device 17 does not operate. In this manner, whether or not to operate the overturn prevention device 17 is set by a prohibition signal corresponding to the permission command or the prohibition command.

  Further, when it is determined that the user wants to get off in the get-off request determination, the control ECU 20 executes landing control (step S9), gently tilts the vehicle body forward, makes the stopper 16 come into contact with the road surface, and performs vehicle control processing. Exit. The vehicle control process is repeatedly executed at predetermined time intervals (for example, every 100 [μs]).

  As described above, in the present embodiment, when the power supply of the system is shut down as an emergency stop, the fall prevention device 17 is activated based on the necessity predicted in advance. Specifically, the fall prevention device 17 operates only when a prohibition signal for prohibiting the operation is not received. When it is determined in advance that the operation of the overturn prevention device 17 is unnecessary in the inclination direction prediction when the inversion control is executed, the overturn prevention device 17 does not operate regardless of the emergency stop. As a result, the burden on the user such as the occupant 15 necessary after unnecessary operation of the overturn prevention device 17 (for example, when the overturn prevention device 17 is an airbag device, a burden for replacement with a new airbag device) is reduced. It can be omitted.

  Further, only when there is a possibility that the vehicle body tilts backward, the operation of the overturn prevention device 17 at the time of emergency stop is permitted. Specifically, the transmission state of the prohibition signal is switched according to the forward inclination probability determined by the inclination direction prediction. When the forward inclination probability is smaller than the predetermined threshold value, the operation of the fall prevention device 17 is permitted. In this case, preparation is made in advance so that the overturn prevention device 17 automatically operates when the power is turned off. Further, when the forward inclination probability is larger than a predetermined threshold, the operation of the fall prevention device 17 is prohibited. In this case, the overturn prevention device 17 does not operate, and the vehicle body posture is maintained in a state where the stopper 16 in front of the vehicle body is grounded, as in normal boarding / alighting.

  In the present embodiment, special landing control is performed to ensure comfort during the forward leaning of the vehicle body when the occupant 15 wants to get off the vehicle. Also good. This further facilitates control system design.

  Next, the inclination direction prediction process will be described.

  FIG. 6 is a diagram showing the relationship between the substantial vehicle body inclination angle and the forward inclination probability in the first embodiment of the present invention, and FIG. 7 is a flowchart showing the operation of the inclination direction prediction processing in the first embodiment of the present invention. is there.

In the present embodiment, state quantities and parameters are represented by the following symbols.
θ _W : Drive wheel rotation angle [rad]
θ ₁ : Body tilt angle (vertical axis reference) [rad]
τ _W : Driving torque (total of two driving wheels) [Nm]
g: Gravity acceleration [m / s ² ]
R _W : Driving wheel contact radius [m]
I ₁ : Body inertia moment [kgm ² ]
m ₁ : Body mass (including passengers) [kg]
l ₁ : Body center-of-gravity distance (from axle) [m]

Subsequently, the main control ECU 21 estimates the shift amount of the vehicle body center of gravity (step S4-2). Specifically, the vehicle body center-of-gravity deviation amount δ ₁ is estimated from the obtained state quantities and the time history of the drive torque by the following equation (1).

Note that the value determined during the previous control process is used as the value of the drive torque τ _W. The values of the vehicle body tilt angle acceleration and the drive wheel rotation angle acceleration are obtained by time-differentiating (differencing) the measured values of the vehicle body tilt angle θ ₁ and the drive wheel rotation angle θ _W twice.

  In the present embodiment, the vehicle body center-of-gravity shift amount is estimated as the deviation of the mechanical model related to the tilt motion of the vehicle body based on the driving wheel rotation state, the vehicle body tilt state, and the drive torque time history. Specifically, the rotational inertia of the vehicle body, the inertial force accompanying acceleration / deceleration of the vehicle 10, gravity torque, and the anti-torque of the drive torque are considered, and it is assumed that the action not taken into account is due to the deviation of the center of gravity of the vehicle body. Thus, the deviation of the center of gravity of the vehicle body is estimated. Therefore, for example, the mechanical and electrical offset of the vehicle body tilt sensor 41 can be automatically taken into account as the center of gravity deviation amount.

  In addition, the low-pass filter removes the influence of disturbance. For example, the influence of the occupant 15's temporary operation, road surface unevenness, sensor signal noise, and the like is excluded.

  In this embodiment, the vehicle body center-of-gravity shift amount is estimated using a simple linear model, but may be estimated using a more rigorous model. For example, the estimation may be performed more strictly by using a model that takes into account factors such as nonlinear action and viscous resistance to vehicle body rotation. Moreover, you may estimate with a simpler model. For example, the estimation may be performed using a model in which the rotational inertia of the vehicle body having a short characteristic time and the inertial force accompanying acceleration / deceleration are ignored. Furthermore, when the vehicle body inclination angular acceleration and the driving wheel rotation angular acceleration are large, the estimated value may be maintained by fixing the estimated value.

  In this embodiment, the estimated value is corrected by the first-order low-pass filter, but a higher-order filter may be used.

  Furthermore, in the present embodiment, the vehicle body center-of-gravity deviation amount is acquired by estimation, but other methods may be used. For example, a plurality of load sensors that measure the load distribution of the riding section 14 including the occupant 15 and the loaded object may be provided, and the riding section 14 and the vehicle body center-of-gravity deviation may be estimated based on the measured values. Thereby, the accuracy and reliability of estimation can be further increased. In this case, other elements not considered in the dynamic model, for example, the offset of the vehicle body tilt sensor 41 may be estimated by the same method as in the present embodiment.

  Furthermore, in the present embodiment, the deviation from the mechanical model relating to the tilt motion of the vehicle body is estimated as the vehicle body center-of-gravity deviation amount, but the deviation may be evaluated by other physical quantities. For example, the reaction torque acting on the vehicle body may be used as a deviation, and the estimated value may be used for vehicle body tilt angle estimation described later. That is, the vehicle body center-of-gravity deviation amount is one of physical quantities corresponding to a deviation from the dynamic model, and is not limited thereto.

  Subsequently, the main control ECU 21 determines a forward inclination probability (step S4-3). In this case, the forward inclination probability P is determined by the following equation (2) according to each acquired state quantity.

  FIG. 6 shows the relationship between the forward inclination probability and the substantial vehicle body inclination angle.

  Note that a predetermined value is given in advance to the predicted value of the braking torque under the following assumptions. First, when a friction brake acts on the drive wheel 12 at the time of an emergency stop, the value of a brake torque which is a predicted performance value or a control command value is given. Further, when the friction brake does not act on the driving wheel 12 at the time of emergency stop, a value corresponding to the braking torque is given in consideration of the counter electromotive force of the driving motor 52 and the rolling resistance of the driving wheel 12.

  Thus, in the present embodiment, based on the state of the vehicle 10, the forward lean probability of the vehicle body is determined as a prediction of the direction in which the vehicle body is inclined when the inversion control is stopped.

  Specifically, the forward lean probability is determined based on the vehicle body tilt angle and the vehicle body tilt angular velocity. In this case, the forward lean probability is increased as the vehicle body is tilted forward and as the vehicle body is tilted forward. Even if the vehicle body is tilted rearward, it is determined that the vehicle body is tilted forward if the vehicle body tilt angular velocity forward is large. Thus, the tilt direction can be predicted with higher accuracy by considering the vehicle body tilt angular velocity.

  Moreover, the influence of the inertia force accompanying the deceleration of the vehicle 10 at the time of an emergency stop is considered. Specifically, the forward lean probability is determined based on the predicted deceleration and deceleration time of the vehicle 10. Further, the deceleration time is predicted based on the vehicle speed or the driving wheel rotation angular speed. In this case, it is determined that the higher the vehicle speed, the longer the time until the vehicle 10 stops and the greater the influence on the vehicle body inclination, that is, the greater the probability of forward inclination. Thus, the inclination direction can be predicted with higher accuracy by considering the inertial force after the emergency stop.

  Furthermore, the forward inclination probability is corrected according to the vehicle body center-of-gravity shift amount. Specifically, the forward lean probability is determined based on the predicted deceleration and deceleration time of the vehicle 10. Further, the deceleration time is predicted based on the vehicle speed or the driving wheel rotation angular speed. In this case, it is determined that the higher the vehicle speed, the longer the time until the vehicle 10 stops and the greater the influence on the vehicle body inclination, that is, the greater the probability of forward inclination. In this way, the inclination direction can be predicted with higher accuracy by considering the shift amount of the vehicle body center of gravity.

  Further, the prediction result of the vehicle body tilt direction is determined as a probability value. Specifically, when the balanced state (the state where the vehicle body does not lean in either direction) is predicted, the forward lean probability is halved, and the greater the mechanical action to lean the vehicle body forward, the greater the forward lean probability. Enlarge. Thus, by outputting the tilt direction prediction result as a quantitative value, the prediction result can be handled flexibly and appropriately.

  In the present embodiment, the vehicle body tilt direction is predicted based on a dynamic model that considers inertia and gravity, but other influences may be taken into consideration. For example, the vehicle body tilt direction may be predicted in consideration of frictional resistance, air resistance, or a shift in the center of gravity of the vehicle body. Furthermore, when the vehicle 10 includes an active weight portion that relatively moves in the horizontal direction, the vehicle body tilt direction may be predicted in consideration of the position and speed of the active weight portion.

  In the present embodiment, the forward slope probability is determined by a non-linear function, but may be determined by a simple function that is linearly approximated. Further, a non-linear function may be provided as a map and determined using the map.

  Further, in the present embodiment, the prediction reliability is set to a predetermined value, but the prediction reliability may be changed according to the situation of the vehicle. For example, when the vehicle acceleration or the vehicle body inclination angular acceleration is larger than a predetermined threshold, or when the road surface shape such as a slope or an uneven road is not flat, the prediction reliability may be lowered. Thereby, a reasonable prediction result corresponding to the actual reliability of the vehicle body tilt direction prediction is output, and appropriate control is executed.

  Further, although it is predicted that the vehicle body tilts forward when the forward lean probability is equal to or greater than a predetermined threshold, the threshold may be changed according to the situation of the vehicle 10 and the like. For example, as with the prediction reliability, the threshold value may be decreased when the acceleration of the vehicle or the vehicle body inclination angular acceleration is larger than a predetermined threshold value, or when the road surface shape is not flat such as a slope or an uneven road. . Thereby, appropriate control according to the actual reliability of vehicle body inclination direction prediction is performed.

  In the present embodiment, the control for urging the vehicle forward is executed on the assumption that the vehicle body tilted forward is more convenient and comfortable. However, the vehicle may be tilted backward. For example, in the case of a standing inverted vehicle that has a handle in front of the vehicle 10 and rides from behind, it may be possible to improve convenience and comfort during ascending / descending by always inclining backward.

  As described above, in this embodiment, the vehicle body getting-off direction inclination probability is calculated, and the vehicle body inclination direction is predicted based on the calculated probability, and when the vehicle body inclination in the getting-off direction is predicted, the fall prevention device 17 Disable operation in advance. Thereby, it is possible to reliably determine the inclination direction of the vehicle body and to reliably operate the overturn prevention device 17 only when necessary.

  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. 8 is a schematic diagram showing the configuration of the vehicle according to the second embodiment of the present invention, and FIG. 9 is a block diagram showing the configuration of the vehicle control system according to the second embodiment of the present invention.

  In the present embodiment, the vehicle 10 includes a weight 71 as a movable mass disposed below the axle 12a. The weight 71 is movable in the front-rear direction of the vehicle body along a guide member 72 extending in the front-rear direction of the vehicle body. The weight 71 and the guide member 72 have a structure such as a linear guide, for example. The guide member 72 is a guide rail, and the weight 71 is a carriage that slides along the guide rail. It has a structure in which rolling elements such as balls and rollers interposed therebetween are arranged. In addition, for example, a structure such as a ball screw is provided, the guide member 72 is a screw shaft provided with a spiral groove, and a weight 71 is provided with a nut that is screwed to the screw shaft, between the screw shaft and the nut. It has a structure in which rolling elements such as balls and rollers intervening are arranged. The front end of the guide member 72 is attached to a front bracket 73 fixed to the stopper 16, and the rear end of the guide member 72 is attached to a rear bracket 74 fixed to the stopper 16.

  A spring member 75 is disposed between the weight 71 and the rear bracket 74 as urging means to urge the weight 71 forward as a specific direction. The spring member 75 is, for example, a compression coil spring, and applies a force that pushes the weight 71 forward.

  Furthermore, the power supply corresponding holder 76a as the first fixing means is attached to the stopper 16, and the control corresponding holder 76b as the second fixing means and the third fixing means is attached to the rear bracket 74. The power supply holder 76a and the control holder 76b are fixing means that can be switched between a fixed state and a released state. In the released state, the weight 71 is allowed to move in the front-rear direction, and in the fixed state, the weight 71 is moved in the front-rear direction. Hinder the move to.

  In the state shown in FIG. 8, the power supply holder 76 a and the control holder 76 b are both in a fixed state, and the forward movement of the weight 71 is prohibited against the urging force of the spring member 75. Thereby, the weight 71 is fixed at a position where the center of gravity is on a vertical line passing through the driving wheel grounding point. The power supply holder 76a and the control holder 76b are not necessarily attached to the stopper 16 and the rear bracket 74, and may be attached to any part of the vehicle body.

  The vehicle 10 further includes a holder control ECU 23 as a vehicle control device. The holder control ECU 23 is a computer system that 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. However, it may be arranged in the support part 13 or the boarding part 14. The main control ECU 21 and the drive wheel control ECU 22 may be configured separately or may be configured integrally.

  And main control ECU21 functions as a part of control corresponding | compatible holder system 80 which controls operation | movement of the control corresponding | compatible holder 76b with the holder control ECU23 and the holder motor 82. FIG. The holder motor 82 operates the control-compatible holder 76b to switch between the fixed state and the released state.

  In the present embodiment, the power supply holder 76a is automatically fixed when the power is turned on and automatically released when the power is turned off. The control-compatible holder 76b is switched between a fixed state and a released state in response to a holder switching command from the main control ECU 21 when the power is turned on, and maintains the state immediately before the power is turned off.

  Note that the holder control ECU 23 may be omitted, and the input voltage of the holder motor 82 may be directly supplied from the main control ECU 21. Since the configuration of other points is the same as that of the first embodiment, description thereof is omitted.

  Next, the operation of the vehicle 10 in the present embodiment will be described.

  In the vehicle control process, similarly to the first embodiment, the control ECU 20 executes the tilt direction prediction process, performs the tilt direction determination based on the result of the tilt direction prediction process, and determines whether or not the vehicle is tilted forward. Determine whether.

  If the vehicle is not leaning forward, the control ECU 20 releases the weight. Specifically, the control corresponding holder 76b is switched to the released state by transmitting a release command signal to the holder control ECU 23. As a result, the forward movement of the weight 71 is blocked only by the power supply holder 76a.

  In the case of forward inclination, the control ECU 20 performs weight fixing. Specifically, the control corresponding holder 76b is switched to the fixed state by transmitting a fixing command signal to the holder control ECU 23. As a result, the forward movement of the weight 71 is blocked by both the power supply corresponding holder 76a and the control corresponding holder 76b. Even when it is determined that the user desires to get off in the get-off request determination, the control ECU 20 similarly performs weight fixing.

  If it is determined in the system abnormality determination that an abnormality has occurred, the control ECU 20 performs power shutdown, that is, an emergency stop, and shuts off the system 10 power supply, as in the first embodiment. Then, the vehicle control process ends. As described above, the power supply holder 76a is automatically fixed when the power is turned on, and is automatically released when the power is turned off. Therefore, when the weight is already released and the control-compatible holder 76b is switched to the released state, the weight 71 moves forward by the biasing force of the spring member 75. As a result, the center of gravity of the entire vehicle body moves forward, so that the vehicle body reliably tilts forward. Further, the reaction force of the spring member 75 that moves the weight 71 forward acts on the rear bracket 74 located below the axle 12a, thereby rotating the rear bracket 74 rearward, that is, the riding section. A rotational moment that tilts 14 forward acts to assist the vehicle body tilting forward. When the weight is fixed and the control-compatible holder 76b is switched to the fixed state, the weight 71 does not move forward even when the power-supply-related holder 76a is released.

  As described above, in the present embodiment, when the power supply of the system is cut off as an emergency stop, the weight 71 as the movable mass automatically moves forward according to the situation of the vehicle 10. . First, when the power is shut off, the power supply holder 76a is in a released state. Therefore, the vehicle body can be reliably tilted forward even when the inversion control due to the power interruption is stopped. Further, the control corresponding holder 76b holds the set state when the inverted control is executed. For this reason, when it is determined in advance that the forward movement of the weight 71 is unnecessary in the inclination direction prediction process when the inversion control is executed, the weight 71 is held at the neutral position regardless of the emergency stop. Therefore, the labor of moving the weight 71 again to the neutral position can be saved when the inversion control is resumed.

  Further, the weight 71 is not moved when the normal inversion control is stopped due to the passenger 15 getting off the vehicle. Specifically, upon receiving an inversion control stop command from the occupant 15, the control corresponding holder 76b is set in a fixed state before shifting to landing control. Thereby, it is possible to save the labor of moving the weight 71 again to the neutral position when reversing the inverted control. Further, the control for tilting the vehicle body forward is not disturbed by the forward movement of the weight 71, and the design of the landing control is facilitated.

  In the present embodiment, a system is assumed in which the weight 71 that has moved forward in response to an emergency stop is manually returned to the neutral position before the inversion control is resumed. The weight 71 may be automatically restored using Even in this case, the present embodiment is very effective in terms of reducing waste of energy and shortening the startup time.

  In the present embodiment, special landing control is performed to ensure comfort during the forward leaning of the vehicle body when the occupant 15 wants to get off the vehicle. Also good. This further facilitates control system design.

  As described above, in the present embodiment, the control corresponding holder 76b is controlled according to the forward lean probability of the vehicle body. Specifically, when the forward inclination probability is equal to or less than a predetermined value, the control corresponding holder 76b is set to the released state. As a result, it is possible to prevent an excessive moment that tilts the vehicle body forward during an emergency stop, and to reduce the risk of an impact at the time of ground contact or vehicle overturning.

  Further, since the weight 71 is positioned vertically below the axle 12a, the moment due to the reaction force of the spring member 75 that urges the weight 71 acts to tilt the vehicle body forward. Thereby, even if the mass of the weight 71 is small, the vehicle body can be more reliably tilted forward.

  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. 10 is a schematic diagram showing the configuration of the vehicle in the third embodiment of the present invention.

  In the present embodiment, the stopper 16 functions as a movable mass instead of the weight 71 and is movable along the guide member 72 in the longitudinal direction of the vehicle body. In addition, the auxiliary | assistant part 13a extended in the front-back direction is fixed to the lower end of the support part 13, and the front bracket 73 and the back bracket 74 are being fixed to the front end and rear end of this auxiliary | assistant part 13a. Moreover, the power supply corresponding holder 76a is attached to the auxiliary portion 13a.

  Other configurations and operations are the same as those in the second embodiment, and a description thereof will be omitted.

  As described above, in the present embodiment, the stopper 16 which is an essential component of the vehicle 10 has an additional role as a movable mass. Thereby, since it is not necessary to add a movable mass again, it is possible to realize a vehicle in which the vehicle body is always inclined forward without greatly increasing the weight of the vehicle. Further, since the stopper moves forward during an emergency stop, the stability of the vehicle body with the stopper grounded is increased, and a safer vehicle can be realized.

  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. 11 is a schematic diagram showing a configuration of a vehicle in the fourth embodiment of the present invention.

  In the present embodiment, the riding section 14 functions as a movable mass instead of the weight 71 and is movable along the guide member 72 in the front-rear direction of the vehicle body. In this case, the upper bracket 77 is fixed on the main body 11 located above the drive wheel 12, and the front end and the rear end of the guide member 72 are attached to the upper bracket 77. And the lower end part 14b of the boarding leg part 14a extended toward the downward direction from the boarding part 14 is attached along the guide member 72 so that the movement to the front-back direction of a vehicle body is possible. Thereby, the riding part 14 can move to the front-back direction as movable mass.

  A spring member 75 is disposed between the lower end portion 14 b of the boarding leg portion 14 a and the upper bracket 77, and a power supply holder 76 a and a control holder 72 b are attached to the upper bracket 77.

  Other configurations and operations are the same as those in the second embodiment, and a description thereof will be omitted.

  As described above, in the present embodiment, the riding section 14 including the occupant 15, which is a large heavy object, has an additional role as a movable mass. Thereby, since it is not necessary to add a movable mass again, it is possible to realize a vehicle in which the vehicle body is always inclined forward without greatly increasing the weight of the vehicle. Further, by effectively utilizing the occupant 15, which is the largest heavy object in the small vehicle 10, a sufficient effect can be obtained even with a short movable distance, so that the vehicle 10 that is lighter, smaller, and less expensive can be realized. Further, since the riding section moves forward during an emergency stop, it is easy for the passenger 15 to get off after the stop.

  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.

  The present invention can be applied to a vehicle using posture control of an inverted pendulum.

DESCRIPTION OF SYMBOLS 10 Vehicle 12 Drive wheel 17 Fall prevention device 20 Control ECU

Claims (12)

A drive wheel rotatably mounted on the vehicle body,
A fall prevention device for preventing the body from falling;
A vehicle control device that controls the attitude of the vehicle body by controlling the drive torque applied to the drive wheels,
The vehicle control device
An inclination direction prediction means for predicting a direction in which the vehicle body is inclined when the control of the posture of the vehicle body is stopped;
A vehicle comprising: prohibiting means for prohibiting execution of the fall prevention device based on a direction in which the vehicle body tilts predicted by the tilt direction predicting means.   2. The vehicle according to claim 1, wherein the prohibiting unit prohibits execution of the overturn prevention device based on a direction in which the vehicle body tilts predicted by the tilt direction prediction unit immediately before stopping control of the posture of the vehicle body. A posture limiting means for limiting the posture angle of the vehicle body;
2. The vehicle control device according to claim 1, wherein the prohibiting unit prohibits execution of the fall prevention device when a direction in which the vehicle body tilt predicted by the tilt direction prediction unit coincides with a direction in which the posture limiting unit functions. Or the vehicle according to 2;   The vehicle according to any one of claims 1 to 3, wherein the inclination direction predicting means predicts a direction in which the vehicle body is inclined according to an inclination state of the vehicle body and / or a rotation state of the drive wheel. The inclination direction prediction means includes a center-of-gravity deviation amount acquisition means for acquiring a center-of-gravity deviation amount of the vehicle body,
The vehicle according to any one of claims 1 to 4, wherein a direction in which the vehicle body tilts is predicted based on a gravity center shift amount of the vehicle body acquired by the gravity center shift acquisition unit.   6. The vehicle according to claim 5, wherein the center-of-gravity deviation amount obtaining unit estimates the center-of-gravity deviation amount of the vehicle body based on a tilt state of the vehicle body and / or a rotation state of the drive wheel and / or a time history of the drive torque. .   The tilt direction predicting means further includes a deceleration state predicting means for predicting a deceleration and a deceleration time of the vehicle after the control of the posture of the vehicle body is stopped based on a traveling speed of the vehicle, and is predicted by the deceleration state predicting means. The vehicle according to any one of claims 1 to 6, wherein a direction in which the vehicle body tilts is predicted based on the deceleration and the deceleration time.   The inclination direction predicting means calculates a probability that the vehicle body is inclined in a specific direction when the control of the posture of the vehicle body is stopped, and predicts that the vehicle body is inclined in a specific direction when the calculated probability is equal to or greater than a predetermined threshold. The vehicle according to any one of claims 1 to 7.   The vehicle according to any one of claims 1 to 8, wherein the vehicle control device shuts off a power source of the vehicle when stopping control of the posture of the vehicle body. The prohibition means transmits a prohibition signal for prohibiting execution of the fall prevention device to the fall prevention device when the tilt direction prediction means predicts that the vehicle body is tilted in a specific direction,
The overturn prevention device is not executed when the prohibition signal is received immediately before the power supply of the vehicle body is shut off, and when the prohibition signal is not received immediately before the power supply of the vehicle body is shut off. The vehicle according to claim 9 to be executed.   The vehicle according to any one of claims 1 to 6, wherein the overturn prevention device operates an airbag that is interposed between the vehicle body and a road surface and limits an inclination angle of the vehicle body within a predetermined threshold.   The vehicle according to any one of claims 1 to 6, wherein the overturn prevention device operates a movable mass that moves the center of gravity of the vehicle body to the opposite side in the direction of overturning.

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