JP2012236546A - Control apparatus for vehicle attitude - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control apparatus for attitude of a vehicle using aerodynamic force, in which control effect is rapidly exhibited.SOLUTION: The control apparatus for the attitude of the vehicle includes: an air-jetting nozzle disposed on a vehicle body and for jetting airflow in a selected direction; and a device for controlling airflow to be jetted from the air-jetting nozzle so that the moment caused by reaction force of the airflow jetted from the air-jetting nozzle acts on the vehicle body in a direction determined based on attitude information of the vehicle body. The airflow from the air-jetting nozzle is jetted in a yaw direction, pitch direction and/or roll direction of the vehicle body, and reaction force thereof causes the moment of force to act on the vehicle body.

Description

  The present invention relates to the field of attitude control devices for vehicles such as automobiles, and more particularly to an apparatus for controlling the attitude of a vehicle by the action of an air flow ejected from a part of a vehicle body.

  In a vehicle such as an automobile, the posture of the vehicle is affected by the force of the airflow flowing around the vehicle body. Therefore, a method has been proposed in which the attitude of the vehicle is controlled by controlling the airflow around the vehicle body. For example, in Patent Document 1, a stagnation point is formed by ejecting air from an air ejection nozzle provided on a side surface of a vehicle body and separating the air flow on the surface of the vehicle body, thereby generating a yaw moment in the vehicle body. A method for generating a negative pressure portion and thereby reducing a yaw moment generated by a cross wind or the like is disclosed (FIG. 4). Patent Document 2 proposes a spats device that provides a spats plate for controlling the air flow in front of the wheels and controls the yaw moment generated in the vehicle by changing the direction of the spats plate according to the steering state of the vehicle. Has been.

JP 06-286670 A JP2009-012763

  In the case of the control method of Patent Document 1, the balance of the aerodynamic force acting on the vehicle body is changed through a two-stage process of air injection and separation of the airflow on the surface of the vehicle body. The time delay until the effect of controlling the aerodynamic force generated in the vehicle body is relatively long. The control mechanism is an indirect separation generating mechanism that induces separation of the air flow from the object surface by attracting the boundary layer of the object surface in the vicinity by an air jet, and air that functions as a separation generating device. Because the jet nozzle is installed in the atmosphere, if a disturbance wind that varies in direction and size acts in the vicinity of the nozzle, the boundary between the attracting force of the boundary layer and the air flow on the attracted side of the vehicle body surface The state of the layer becomes unstable, and therefore control of air flow separation can be quite difficult. On the other hand, in the configuration of Patent Document 2, since the spats plate is provided in front of the wheels, only the air flow in the lower part of the vehicle body is controlled, and the vehicle posture control is mainly performed only in the yaw direction. It is.

  Thus, an object of the present invention is to provide a vehicle attitude control device that uses aerodynamic force and that is configured to exhibit a control effect more quickly than a conventional device.

  Another object of the present invention is to provide an apparatus as described above, which can also correct the posture of a vehicle in a direction other than the yaw direction.

  According to the present invention, the above-described problem is a vehicle attitude control device, which is determined based on an air ejection nozzle provided on the vehicle body and capable of ejecting an air flow in a selected direction, and vehicle attitude information. And a means for controlling the air flow ejected from the air ejection nozzle so that the moment caused by the reaction force of the air flow ejected from the air ejection nozzle acts on the vehicle body.

  In the above configuration, for example, an air ejection nozzle capable of ejecting an air flow in the direction selected at the rear end of the vehicle body is provided on the vehicle body, and the reaction force of the air flow ejected from the air ejection nozzle is provided. A force moment is generated in the vehicle body, thereby achieving control of the vehicle body posture. For example, a plurality of air ejection nozzles may be provided so that the air flow is directed in the vertical direction, the horizontal direction, and the angular direction, and the amount of air is preferably controllable independently in each direction. As for the ejected air, an air supply device may be mounted on the vehicle, whereby the ejected air may be supplied. In this regard, for the purpose of reducing the weight and / or size of the air supply device, particularly in the case of an electric vehicle, a gas turbine engine is mounted as a power source of the range extender of the battery charging system (gas turbine engine). Is used for charging the battery.) When the air flow is ejected, the output of the gas turbine engine is switched from the generator for charging the battery to the air supply device so that the output of the gas turbine can be used as a power source for the air flow ejection. It may be.

  In the air flow control means, typically, the vehicle speed, the three-axis (x, y, z-axis) acceleration, the yaw rate, etc. are constantly monitored, and whether or not the attitude control by the air flow is necessary. It may be determined. When it is determined that the attitude control by the air flow is necessary, the required flow rate in each of the air ejection nozzles is based on the above monitoring data and the pressure upstream of the flow control valve provided in each of the air ejection nozzles. In addition, the opening degree of the flow control valve is determined, and an opening degree control signal is transmitted to each control valve, and the determined air amount is ejected in each control valve, thereby applying a moment of force to the vehicle body. You may be supposed to.

  Thus, according to the present invention, since the reaction force of the air jet flow directly generates a moment for controlling the posture of the vehicle body, the time until the effect of controlling the aerodynamic force generated on the vehicle body from the control instruction is obtained. It can be made relatively short. In addition, since the reaction force of the air jet flow depends on the flow rate and flow velocity of the air jetted from the nozzle, even if turbulent wind hits the nozzle, the effect appears remarkably in the moment generated by the reaction force of the air jet flow. Therefore, stable control is expected. Furthermore, since the direction of the air jet flow can be arbitrarily set by setting the nozzle direction arbitrarily, the attitude control of the vehicle can be performed not only in the yaw direction but also in the pitch direction and the roll direction. In a vehicle equipped with a battery charging system such as an electric vehicle, the air supply device needs to have a dedicated power source by using the power source of the range extender as the power source of the air supply device. This makes it possible to reduce the weight and size of the device.

  Other objects and advantages of the present invention will become apparent from the following description of preferred embodiments of the present invention.

FIG. 1 is a schematic plan view for explaining the principle of vehicle attitude control according to the present invention. FIG. 2 is a side view (A) and a rear view (B) schematically showing a vehicle on which the vehicle attitude control device according to the present invention is mounted. FIG. 3 is a block diagram showing the configuration of the vehicle attitude control device according to the present invention. FIG. 4 schematically shows an example of a vehicle attitude control mode executed through control of the air flow around the vehicle in the prior art.

DESCRIPTION OF SYMBOLS 10 ... Vehicle 12F, 12R ... Wheel 14 ... Air injection nozzle 15 ... Flow control valve 16 ... Air piping 18 ... Air supply device 20 ... Gear 22, 25 ... Clutch 24 ... Small gas turbine 26 ... Generator 28 ... Battery 30 ... Release Wind valve 50 ... Electronic control unit

  The present invention will now be described in detail with reference to a few preferred embodiments with reference to the accompanying drawings. In the figure, the same reference numerals indicate the same parts.

As described above, in a traveling vehicle such as an automobile, the force of airflow that flows around the vehicle body can generate a moment of force that changes the posture of the vehicle. Therefore, for example, in Patent Document 1, as shown in FIG. 4, a nozzle 14 ′ for injecting air is provided on the side portion of the vehicle body 10, and the air flow around the vehicle body is controlled to thereby change the posture of the vehicle. A configuration to control has been proposed. In this configuration, to put it briefly, when the vehicle 10 receives the cross wind F from the left front as shown in the figure, and a yaw moment I is generated around the center of gravity G, the air is injected from the air injection nozzle 14 'on the left side of the vehicle body. Stream J is injected. Then, the air flow on the vehicle body surface inside the air flow J is separated and becomes a stagnation point. The stagnation space H becomes a negative pressure region in which the pressure is relatively low compared with the surrounding area, so that the vehicle body is attracted, and a yaw moment K around the center of gravity G is generated. Will be offset.

  However, when the yaw moment K is generated by the mechanism illustrated in FIG. 4, a two-stage process of air injection and airflow separation on the surface of the vehicle body is performed, so that the yaw moment K is generated after the transmission of the control instruction. The time delay until is relatively long. Further, as shown in the figure, when a part of the cross wind (disturbance wind) F hits the air injection nozzle 14 ', the attractive force of the boundary layer of the air flow on the surface of the vehicle body by the air injection flow and the state of the boundary layer itself on the attracted side And therefore, control of air flow separation can be quite difficult.

  Therefore, in the present invention, an attitude control device using the force of air flow based on a novel principle that does not cause the problems in the conventional techniques as described above is proposed. In the posture control apparatus of the present invention, as schematically shown in FIG. 1, the air injection nozzle 14 is provided at a position away from the center of gravity G of the vehicle body 10, for example, at the rear end of the vehicle body. When a force moment I is generated in the vehicle body due to a disturbance, an air flow J is ejected from the air injection nozzle 14 so that a force moment K is generated in a direction to cancel the force moment I due to the disturbance. It should be understood that the moment K of the force generated by the air flow J depends on the reaction force against the jet of the air flow J. According to such a configuration, since the moment K of force is generated in response to the ejection of the air flow J, the time delay from the transmission of the control instruction to the generation of the yaw moment K is relatively short. In addition, since the magnitude of the reaction force of the air flow J is determined by the amount of air jetted from the air injection nozzle 14 per hour, even if disturbance air hits the air injection nozzle 14, The effect on reaction force is relatively small.

  In FIG. 1, the air flow J is generated in order to generate a moment K of the force caused by the jet of the air flow J in a direction that cancels the yaw moment I with respect to the disturbance wind F that changes the posture of the vehicle body in the yaw direction. Is described to be ejected to the side of the vehicle body. However, when a moment of force occurs due to a disturbance that changes the posture in the pitch direction or roll direction in the vehicle body, the force is applied in a direction that cancels out the force moment corresponding to the direction of the disturbance force moment. It is preferable that the air flow J can be selectively ejected in the vertical direction or the angular direction of the vehicle body so that a moment is generated (see FIG. 2B).

Configuration of Device Referring to FIG. 2, a vehicle 10 such as an automobile on which a vehicle attitude control device according to the present invention is mounted may be a vehicle such as an arbitrary automobile. The vehicle 10 is mounted with a power device that generates braking / driving force on each wheel 12F, 12R, a steering device, and a braking device that generates braking force on each wheel in a normal manner (not shown). ). In the illustrated example, the vehicle is an electric vehicle, and the battery 28 is mounted on the bottom of the vehicle body. However, the present invention is not limited to this and may be an engine vehicle or a hybrid vehicle.

  The vehicle attitude control device of the present invention includes, as a basic configuration, an air injection nozzle 14 that ejects an air flow, an air supply device 18 that supplies the air flow to the air injection nozzle 14, and a pipe 16. The air injection nozzle 14 is disposed at a position as far as possible from the center of gravity of the vehicle, typically at the rear end of the vehicle body as shown in the drawing, so that a moment of force due to the reaction force of the air flow ejection is increased. In more detail, the air injection nozzle 14 has a nozzle 14a directed in the left-right direction of the vehicle body so that a force can be generated in the yaw direction of the vehicle body, as schematically illustrated in FIG. 14b and nozzles 14c to 14f facing the up and down direction of the vehicle body so that force can be generated in the pitch direction and the roll direction of the vehicle body. Each nozzle is provided with a flow rate control valve 15 that allows the air flow sent from the pipe 16 to be ejected in a manner in which the flow rate can be adjusted. Under the control of the electronic control unit 50, the air flow is controlled independently of each other, and the air flow can be selectively ejected from the corresponding nozzle.

  The air supply device 18 may typically be any type of compressor or the like that can take air from the outside from one end (front end) and pump the air flow to the other end (rear end). The power source of the air supply device 18 may be an arbitrary rotary drive device. For the purpose of reducing the weight and the size of the air supply device 18, the rotational drive force of the existing rotary drive device is used in the vehicle. It is preferable that the air supply device 18 be configured to be used as a driving force. In particular, when the vehicle 10 is an electric vehicle and a small range extender (a system that generates power using fuel in the vehicle and charges the battery 28) is mounted, the gas turbine engine 24 is used as a power source of the range extender. (The reason why the gas turbine engine is adopted is that the output per weight is the minimum.) The air supply device (compressor for driving the generator 26 for charging the battery and the air flow injection) ) It can be used for both 18 driving. In this case, when charging the battery, the clutch 22 that transmits the rotational force from the gas turbine engine 24 to the air supply device is turned off (intermittent), and the clutch 25 that transmits the rotational force from the gas turbine engine 24 to the generator 26 is turned on. By making (connection), the generator 26 is driven and charging of electricity is executed. On the other hand, when the attitude control of the vehicle is executed, the clutch 25 is turned off and the clutch 22 is turned on, so that the rotational force is transmitted from the gas turbine engine 24 to the air supply device (compressor) 18 through the gear 20. Communicated. Note that switching of the ON / OFF states of the clutch 22 and the clutch 25 may be achieved by driving an arbitrary type of actuator under the control of the electronic control unit 50.

  By the way, when the attitude control of the vehicle is executed, the air supply device 18 starts to be driven in response to the control start instruction, and the air flow is actually supplied to the nozzle 14. It takes time to be ejected from the nozzle, and the control response is delayed. Therefore, it is preferable that the air supply device 18 is always operated to supply an air flow to the pipe 16 and to release the air flow from the discharge valve 30 when it is not necessary to eject the air flow from the nozzle 14. It may be configured to be able to. In that case, when the air flow ejection from the nozzle 14 is necessary, the air flow escape path from the air discharge valve 30 is blocked, and the corresponding flow control valve 15 is ejected from the nozzle 14 in a desired direction. Is opened. According to such a configuration, it is expected that a moment of force for controlling the attitude of the vehicle is generated promptly in response to the control instruction, and a control effect appears promptly. Note that when the airflow is released from the air discharge valve 30, the airflow may be released in a direction that does not affect the posture of the vehicle body, for example, in the rear of the vehicle body. The position of the air discharge valve 30 is preferably a position as close as possible to the nozzle 14 in order to enhance the responsiveness.

  The operation of each part of the vehicle attitude control device is controlled by the electronic control device 50 as already mentioned. The electronic control unit 50 may include a microcomputer having a CPU, a ROM, a RAM, and an input / output port device, which are connected to each other by a bidirectional common bus, and a driving circuit. As shown in FIG. 3, the electronic control unit 50 includes parameters necessary for attitude control detected by an arbitrary sensor, for example, vehicle speed (or wheel speed), 3-axis (x, y, z-axis) acceleration. A value such as a yaw rate is input. Moreover, in order to monitor the pressure in each flow control valve 15 provided in the nozzles 14a to 14f, a pressure value upstream of each valve may be input. Then, the electronic control unit 50 determines the necessity of attitude control and the determination of the air flow ejection direction and the ejection amount based on the input detection value according to a program stored in a storage device (not shown). This is executed and a control instruction is given to the clutch, the air discharge valve 30 and / or the actuator of each flow control valve 15, thereby controlling the operation of the air supply device 18 and the flow control valve 15.

Operation of the Device In the operation of the vehicle attitude control device according to the present invention, the driving of the air supply device 18 may be started while the vehicle is running, for example, when the vehicle speed exceeds a predetermined speed. Then, as schematically illustrated in FIG. 3, the electronic control unit 50 refers to the vehicle speed, the triaxial acceleration, the yaw rate, and the like, and in any manner, the yaw direction, the pitch direction, and the roll direction of the vehicle. An index value (posture state index value) is calculated to indicate whether or not it is necessary to add a yaw moment to correct the posture in each direction, that is, attitude control by airflow ejection of the vehicle body ( Decide whether car body aerodynamic control is necessary. Here, unless it is determined that the posture control is necessary, a control signal (fully closed signal) for fully closing the valve is given to the full flow control valve 15 to the actuator of each valve, A signal is provided to set the valve to allow airflow to escape.

  On the other hand, for example, if it is determined that the posture of the vehicle body deteriorates due to the cross wind F (see FIG. 1) or some other factor and the posture control is necessary based on the posture state index value, any arbitrary In the aspect, the moment of force required to correct the posture in the yaw direction, pitch direction, and / or roll direction is calculated based on the posture state index value, and the air moment to achieve the force moment is calculated. The ejection amount is calculated, and the required value of the opening degree of each flow control valve is calculated based on the ejection amount of the air and the pressure upstream of each flow control valve. Then, a control signal is transmitted to the actuator of the flow control valve 15 so as to achieve the required value of the opening degree of each flow control valve, and the valve opening operation is executed in the corresponding flow control valve 15, thereby A moment of force for correcting the posture is generated by the ejection of the air flow.

  In the above attitude control, when generation of a moment in the yaw direction is required, the nozzle 14a or 14b is opened while adjusting the flow rate, and an air flow is ejected. Then, a force acts in the direction opposite to the air flow ejection direction in the left-right direction of the vehicle body, thereby generating a yaw moment. When generation of a moment in the pitch direction is required, the nozzles 14d and f or the nozzles 14c and e are opened while adjusting the flow rate, and an air flow is ejected (nozzles 14d and 14f and nozzles 14c and 14e). Are opened at the same time.) As a result, a force acts in the direction opposite to the air flow ejection direction in the vertical direction of the rear end of the vehicle body, thereby generating a moment of force in the pitch direction. Further, when generation of a moment in the roll direction is required, the nozzles 14c and f or the nozzles 14d and e are opened while adjusting the flow rate, and an air flow is ejected (nozzles 14c and 14f and nozzles 14d and 14e). Are opened at the same time.) As a result, in the angular direction around the longitudinal axis of the vehicle body, a force acts in a direction opposite to the air flow ejection direction, thereby generating a moment of force in the roll direction. The air flow rate ejected in each case may be determined based on the posture state index value using, for example, a map prepared experimentally or theoretically in advance.

  When the posture control is no longer necessary after the posture control by the air flow ejection, the full-close signal is again given to the actuator of each valve for the total flow control valve 15, and the air flow is sent to the air discharge valve 30. A signal is set to set the valve to miss. In the case where there is no need for attitude control, the total flow control valve 15 may be opened instead of letting the air flow in the pipe 16 escape by the air discharge valve 30. In that case, when the generation of the moment in each direction is required, the valves other than the flow control valve 15 selected to inject the air flow that gives the required moment of force are closed.

  Thus, according to the above configuration, after a control instruction is given, a moment of force acts on the vehicle body at the same time as the air flow is ejected from the nozzle, so that the effect of posture control is expected to appear quickly. . It should be understood that the control method according to the present invention is capable of correcting the posture even when the vehicle tire is not in contact with the road surface, unlike the conventional posture control by controlling the tire force. Therefore, the present invention can also be applied to attitude control of “flyable mobility”.

  Although the above description has been made in relation to the embodiment of the present invention, many modifications and changes can be easily made by those skilled in the art, and the present invention is limited to the embodiment exemplified above. It will be apparent that the invention is not limited and applies to various devices without departing from the inventive concept.

Claims (1)

  An attitude control device for a vehicle, which is provided on a vehicle body and capable of ejecting an air flow in a selected direction, and is ejected from the air ejection nozzle in a direction determined based on the attitude information of the vehicle body. And means for controlling an air flow ejected from the air ejection nozzle so that a moment caused by a reaction force of the air flow acts on the vehicle body.

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