JP2004051022A - Vehicle operation device - Google Patents

Abstract

An object of the present invention is to improve the operability during driving by providing a natural self-alignment with an appropriate reaction force in a driving operation device that performs steering by a steer-by-wire method.
In a driving operation device for a vehicle having an operation reaction force motor for applying an operation reaction force to an operation unit operated by a driver, a target turning operation reaction force setting unit controls an operation of the operation unit. A return / return determining means for determining a return operation and a return operation, and a reaction force control means for increasing a reaction force of the operation reaction force motor 19 only when the return / return determination means determines a return operation are provided.
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a driving operation device for turning steered wheels of a vehicle.
[0002]
[Prior art]
2. Description of the Related Art A steering system using a steering wheel is known as a driving operation device for turning steered wheels of a vehicle. In this steering system, turning motion of a steering wheel is converted into linear motion of a rack shaft in a steering gear box, and a steered wheel is steered by driving a link mechanism connected to the rack shaft.
[0003]
Here, in recent years, a driving operation device that turns a steered wheel of a vehicle by using a lever or the like instead of the steering wheel has been proposed. No. 301193 is mentioned. This driving operation device is configured to use a driving operation lever (control knob) and operate the lever back and forth and left and right to perform acceleration / deceleration and turning of the vehicle. For example, the vehicle accelerates when a forward operation force is applied to the lever, and decelerates when a rear operation force is applied to the lever. When a rightward operation force is applied to the lever, the steered wheels are steered to the right, and when a leftward operation force is applied, the steered wheels are steered to the left. In addition, examples have been reported in which a plurality of levers are provided with equivalent functions to improve the degree of freedom and reliability of the layout, or to enable operation even when sitting on either the left or right seat.
[0004]
When this lever is used, a so-called steer-by-wire system is adopted in which the steering device and the steering device mechanism are mechanically separated, and a steering motor provided in the steering device mechanism is electrically controlled from the steering device. In some cases, a steer-by-wire is formed using a steering wheel. In such a case, since the lever is not mechanically connected to the steered wheel, the external force applied to the steered wheel is not transmitted to the lever, and the driver cannot obtain a response to the steering operation as it is, and the steering angle and the operation The feeling corresponding to the quantity cannot be obtained.
[0005]
In this regard, in the steer-by-wire system, a reaction force is applied by using a reaction force motor so that a feeling corresponding to the steering angle and the operation amount can be obtained. For example, a steer-by-wire “driving operation device” described in Japanese Patent Application Laid-Open No. 2000-108914 discloses a control amount based on a steering angle and a control based on a vehicle behavior state detected by a behavior state detection unit (yaw rate sensor). Based on the amount, a control amount for the operation reaction force applying means (reaction force motor) is set. Therefore, the influence of the external force acting on the steered wheels due to the change in the behavior of the vehicle can be reflected on the operation reaction force.
[0006]
By the way, in a normal car that is not a steer-by-wire system, for example, when turning around an intersection and returning to a straight-ahead state, a reaction force from the road surface called self-aligning torque is applied, and a special steering operation is applied to the steering wheel. Even without the steering wheel, the steering wheel naturally returns to the straight traveling state (neutral position), and the steering operation does not proceed too much more than the straight traveling state.
[0007]
On the other hand, in the steer-by-wire system, a centering spring (or an elastic body such as rubber) may be used to return a lever, a steering wheel, and the like (hereinafter, referred to as a “lever”) to a center position (a centering mechanism). Use of the centering spring is convenient because the lever naturally returns to the center position when the driver releases his / her hand from the lever.
[0008]
When such a centering spring and a reaction motor are used, the force acting on the lever is a resultant of the reaction force of the reaction motor and the force of the centering spring. Here, the force by the centering spring is applied to the neutral position in proportion to the operation angle (the tilt angle of the lever or the rotation angle of the steering wheel) regardless of the operation going back and forth. Further, the reaction force given by the conventional reaction force motor is a reaction force called so-called virtual torsion bar control given according to the magnitude of the deviation between the target value of the steering angle and the actual steering angle (rack position). is there. This reaction force is controlled so as to be large when the deviation is large and to be small when the deviation is small.
[0009]
[Problems to be solved by the invention]
However, when the lever is returned to the neutral position by using the centering spring when the hand is released after operating the lever to one side, an operation such as the self-aligning torque of a normal vehicle cannot be expected. That is, in general, the return of the lever to the neutral position precedes the return of the steered wheels to the neutral position due to the self-aligning torque. Then, a deviation occurs between the target value of the steered angle and the actual steered angle. As a result, an instruction not intended by the driver to return the steered wheels to the neutral position from the lever side is issued. For this reason, the steered wheels try to return to the neutral position earlier than expected by the driver. This gave the driver a sense of incongruity and also made the driving jerky.
[0010]
In particular, since the reaction force by the centering spring and the reaction force motor is mainly set to the operation of bending the steered wheels, in the case of return, the reaction force tends to be too effective, turning at the intersection at a right angle and going straight In such a case, the returning operation is difficult, giving a sense of incongruity to the driver's operation, and the steering is jerky.
[0011]
Furthermore, since the self-aligning torque changes depending on the road surface conditions, vehicle speed, etc., the return speed of the steered wheels changes, but the return speed of the lever depends on the magnitude of the self-aligning torque because the spring constant of the centering spring is constant. Be constant. For this reason, the difference between the position of the lever and the position of the steered wheel greatly differs depending on the situation, and further, gives the driver a sense of incongruity.
[0012]
FIG. 2A shows the relationship between the vehicle speed, the operating angle, the steering angle, and the output (yaw rate) of the yaw rate sensor for detecting the turning state of the vehicle when the vehicle crosses the intersection at a right angle and returns to the straight running state by the conventional reaction force. Shown as a chart. In this case, the operation angle is returned earlier than the driver thinks, and the operation of the vehicle is jerky because the driver corrects the operation angle (see a portion surrounded by a broken line in the figure). .
[0013]
Therefore, a main problem of the present invention is to provide an appropriate reaction force with a simple configuration when steering a steered wheel by a steer-by-wire method using an operation unit, so that an operation feeling close to the self-aligning of a normal vehicle is achieved. An object of the present invention is to provide a driving operation device for a vehicle, which can obtain a ring, does not cause a sense of incongruity in operation of a driver, and can improve operability when driving the vehicle.
[0014]
[Means for Solving the Problems]
In order to solve the above-described problem, the invention according to claim 1 of the present invention is directed to an operation unit operated by a driver, an operation amount detection unit detecting an operation amount of the operation unit, and at least the operation amount detection unit detects the operation amount. Control means for controlling the actual steering amount of the steered wheels based on the operation amount; a centering spring for returning the operation section to a neutral position; and a reaction force applying means for applying an operation reaction force to the operation section in an operation direction. A drive operation device for a vehicle having a return operation determining means for determining a return operation and a return operation of the operation of the operation unit; and a reaction force applied by the reaction force applying means when the return operation determination means determines a return operation. And a reaction force control means for increasing the number of times in the going operation.
[0015]
Thereby, the reaction force applied to the operation unit at the time of the return operation is increased, and the return speed of the operation unit approaches the speed at which the steered wheels return with the self-aligning torque, thereby preventing the control device from performing unnecessary control. The operability of the vehicle can be improved without discomfort of the driver. In addition, "increase the reaction force ..." includes, for example, a case where a reaction force that is zero (or minus) is set to a value equal to or more than zero, a case where the reaction force that is zero or more is further increased, and the like.
[0016]
Further, the invention of claim 2 of the present invention is characterized in that the going-back determining means determines the going operation and the returning operation from the positive or negative of the differential value of the absolute value of the operation amount detection value of the operation detecting means.
Thus, it is possible to accurately determine the going operation and the returning operation of the operation of the operation unit.
[0017]
Further, the invention according to claim 3 of the present invention has an operation amount change speed detecting means for detecting a change speed of the operation amount, and the reaction force control means provides a reaction force to be controlled to the operation amount change speed detection means. Is characterized in that it has an operation amount change speed responsive reaction force adjustment means that decreases when the change speed of the operation amount detected is large and increases when the change speed is low.
This makes it possible to reduce the reaction force when the driver intends to return quickly by taking in the driver's intention.
[0018]
Further, the invention of claim 4 of the present invention has a vehicle speed detecting means for detecting a vehicle speed, and the reaction force control means has a large reaction force to be controlled when the vehicle speed detected by the vehicle speed detecting means is low. Vehicle speed response reaction force adjusting means for reducing the speed when the vehicle speed is short.
This makes it possible to increase the reaction force at a low vehicle speed, such as when turning at an intersection, to obtain an operation feeling close to the self-aligning torque of a normal vehicle.
[0019]
The invention of claim 5 of the present invention is characterized in that the reaction force control means increases the control force to be controlled when the operation amount of the operation unit detected by the operation amount detection means is large, and decreases when the operation amount is small. It is characterized by having an operation amount responsive reaction force adjusting means for performing the operation amount responsive reaction force adjusting means.
As a result, it is possible to eliminate a sense of incongruity at the time of turning from return to going near the turning center, and to increase the effect of the reaction force when returning after turning a large turning angle, such as when turning around an intersection. You can do so.
[0020]
Further, the invention according to claim 6 of the present invention has an operation torque detection means for detecting an operation torque applied to the operation section, and the reaction force control means reduces a reaction force to be controlled when the operation torque is large, It is characterized by having a torque-responsive reaction force adjusting means for increasing the operating torque when the operating torque is small.
This makes it possible to reduce the reaction force when the driver is strongly operating to take back the driver's intention and return quickly.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings.
[0022]
The basic concept of the present invention will be described with reference to a functional block diagram of FIG. 1 and a comparison diagram of control data of FIG. According to the conventional steer-by-wire steering method of steered wheels, when a driver operates an operating unit such as a lever, a reaction force is applied to the operating unit, and the driver's hand responds to the operation according to the operation. I was trying to join. This reaction force is a component proportional to the operation angle of the operation unit given by the centering spring (a loop including K1 in FIG. 1), a target steering angle given by the operation angle of the operation unit, and an actual steering angle (rack position). ) And a component called a virtual torsion bar control (a loop including K2 in FIG. 1) provided by the reaction force motor in accordance with the magnitude of the deviation. Note that the operation angle corresponds to the "operation amount" in the claims, and the turning angle corresponds to the "steering amount" in the claims.
[0023]
Among them, the component K1 of the reaction force proportional to the operation angle is given by a mechanical return spring (centering spring (elastic body such as rubber)), and the direction of the operation (in the direction of increasing the operation angle (absolute value)) is increased. On the other hand, a return force (a direction in which the operation angle (absolute value) is reduced) is given with the same magnitude as the assist force with respect to the return (the direction in which the operation angle (absolute value) is reduced). The spring constant K1 that gives the magnitude of this force is adjusted to the going reaction force in consideration of safety, so that it tends to work slightly stronger in the case of return. When returning to the vehicle after turning around an intersection, expecting the self-aligning torque of a normal vehicle, if you try to return the operating parts such as levers with your hands lightly, you will return earlier than intended by the driver. There is a risk of passing. In the steer-by-wire system, the position of the wheel (steering angle) is controlled based on the operation angle of an operation unit such as a lever, and such excessive return affects the actual movement of the vehicle. Therefore, the driver needs to perform a correction operation, and the vehicle is jerky.
[0024]
FIG. 2A shows the relationship between the vehicle speed, the operating angle, the steering angle, and the output (yaw rate) of the yaw rate sensor for detecting the turning behavior of the vehicle when the vehicle crosses the intersection at a right angle and returns to the straight running state by the conventional reaction force. Shown as a chart. In this case, the turning angle is returned earlier than the driver thinks, and the driver performs the turning angle correction, so that the movement of the vehicle is jerky.
[0025]
In the present embodiment, various studies have been made in order to solve this problem. As a result, additional control is performed to increase the reaction force given by the reaction force applying means (reaction motor) at the time of the return operation as compared with the time of the go operation (see FIG. (A loop including K3 of 1) was added to solve this problem. The going-back determining means used for the additional control determines the going operation and the returning operation from the positive or negative of the differential value of the absolute value of the operation angle detection value of the operation amount detecting means. In addition, parameters for changing the reaction force corresponding to the running speed (vehicle speed), operation angle, operation angular speed, operation torque, and the like of the vehicle are added to the additional control, and the reaction force is optimally set by these elements. The operation unit is returned at the same speed as the speed at which the steered wheels return by the self-aligning torque, so that unnecessary control of the control means is eliminated, so that the driver does not feel uncomfortable. Furthermore, these factors make it possible to sense the driver's intentional driving and suppress the reaction force.
[0026]
By controlling the reaction force to be increased only at the time of the return operation as described above, the relationship between the vehicle speed, the operation angle, the steering angle, and the output of the yaw rate sensor with respect to the time when the vehicle turns right at the intersection and returns to the straight traveling state is shown in FIG. This is shown in the time chart of FIG. As compared with the case of FIG. 2A, the steering angle does not return earlier than the driver thinks, and the operation angle, the steering angle, and the output of the yaw rate sensor have no irregularities, and the vehicle moves smoothly. (Refer to the portion surrounded by the broken line in FIG. 2B).
[0027]
Subsequently, a specific configuration of the embodiment according to the present invention will be described.
FIG. 3 is a configuration diagram of the vehicle driving operation device according to the present embodiment.
As shown in FIG. 3, the driving operation device realizes a steer-by-wire operation, and the operation unit 1 includes a lever 11. The operation amount of the lever 11 is processed by the control device 4. The steered wheels W are steered by driving the steering motor 5 of the steering mechanism 2 based on the processing result.
[0028]
Here, to steer the steered wheels W, W, the rotation of the steering motor 5 is converted into the linear motion of the rack shaft 7 by the ball screw mechanism 9, and this is simply converted to the steered wheels W, W via the tie rods 8, 8. This is performed by the turning mechanism 2 that converts the turning motion. In other words, the linear movement of the rack shaft 7 is performed by the steering motor 5 and the ball screw mechanism 9 which replace the conventional rack and pinion mechanism. The position of the rack shaft 7 during the linear movement is detected by the steering angle (steering amount) sensor 10 and is fed back to the control device 4. Incidentally, the steering angle sensor 10 is a rack position sensor that detects a steering angle by detecting a rack position, and a known sensor such as a linear encoder or a potentiometer provided along the rack axis is used. It is also possible to use a combination of sensors. Incidentally, the output of the steering angle sensor 10 is also processed by the control device 4 in the same manner as the output of the operation torque sensor 15 and the operation angle sensor 16 described later.
In FIG. 3, the operation amount detecting means 12 and the operation reaction force motor 19 will be described later in detail.
[0029]
Next, the operation unit 1 will be described.
As shown in FIG. 4, the operation unit 1 includes a lever 11 operated by a driver, an operation amount detection unit 12 that detects an operation amount of the lever 11, and a frame unit 13 that holds the operation amount detection unit 12. are doing.
[0030]
The upper portion of the lever 11 is operated by the driver's hand, and one end portion 14a of the rod 14 is fixed to the lower portion. The rod 14 is fixed so as to be orthogonal to the lever 11, and is pivotally supported on the walls 13 a, 13 b, 13 c, 13 d of the frame 13 by bearings or the like. This allows the lever 11 to be tilted and operated so as to rotate in the left-right direction with the rod 14 as a support shaft. Hereinafter, tilting the lever 11 to the right with the rod 14 as a support shaft to steer the steered wheels W, W to the right is referred to as right turning operation, and tilting the lever 11 to the left with the rod 14 as a support shaft. Turning the steered wheels W, W to the left will be described as a left steering operation.
[0031]
The operation torque sensor 15 and the operation angle sensor 16 as the operation amount detecting means 12 are arranged along the longitudinal direction of the rod 14.
[0032]
Among these, the operation torque sensor 15 is a known sensor using a strain gauge or the like, and detects the amount of torque applied to the lever 11 to start operation or change the direction of the steered wheels W, W (when turning back). ) Is improved. Here, the operation torque sensor 15 of the present embodiment outputs an analog of 0.1 V to 4.9 V. The CPU (Central Processing Unit) constituting the control device 4 inputs this as a digital signal. Then, the digital signal is offset by a predetermined value so that 2.5 V at the analog output becomes the zero point. That is, the control device 4 changes the output of the operation torque sensor 15 to a value (detection value Ts) when the lever 11 is turned rightward from the neutral position and a value (detection value Ts) when the lever 11 is turned leftward from the neutral position. Is processed as a positive / negative value such that becomes negative. Thus, the output characteristics of the operation torque sensor 15 recognized by the control device 4 are as shown in FIG. The output (detected value Ts) from the operation torque sensor 15 is used for FF (Feed-Forward) control described later.
[0033]
The operation angle sensor 16 is configured by a potentiometer that detects a rotation angle of the rod 14 by operating the lever 11. The operation angle sensor 16 outputs the operation angle of the lever 11 as a voltage value (detection value θs). The CPU of the control device 4 processes the output of the operation angle sensor 16 in the same manner as the output of the operation torque sensor 15 described above. That is, as shown in FIG. 6, when the reference voltage value when the lever 11 is in the neutral position is set to the neutral position (point 0) and the right turning operation is performed, the detected value is determined according to the rotation amount of the lever 11. When θs increases and the left steering operation is performed, the detected value θs decreases according to the rotation amount of the lever 11. The output (detected value θs) from the operation angle sensor 16 is used by the control device 4 to set the steered angle of the steered wheels W, W.
[0034]
Further, the other end of the rod 14 has a pulley 17, which is connected to a rotating shaft of an operation reaction motor 19 via a belt 18.
The operation reaction force motor 19 receives a signal from the control device 4 and cooperates with a centering mechanism 20 described below to operate the lever 11 in accordance with the position and operation direction of the lever 11 (lever 11). ) And a function of generating a reaction force (operation reaction force) having a different direction and a predetermined magnitude, thereby improving the operability and accuracy of the steering operation.
[0035]
For example, if the lever 11 is pushed further to the right while the right-turning operation is being performed, the centering mechanism 20 generates an operation reaction force in a direction opposite to the direction of the right-turning operation. At this time, since the centering mechanism 20 generates a larger operation reaction force as the operation amount of the lever 11 is larger, the driver can sense the current steering angle and the operation amount of the driver himself based on the magnitude of the reaction force. it can.
The control device 4 gives a signal to the operation reaction force motor 19 via the operation reaction force motor control signal output section 40 and the operation reaction force motor drive circuit 41, and the reaction force applied to the lever 11 by the operation reaction force motor 19 will be described later. Details will be described.
[0036]
A centering mechanism 20 for urging the lever 11 to return to the neutral position is provided between the lever 11 and the operation angle sensor 16. The centering mechanism 20 includes a plate 20a fixed to the rod 14, and centering springs 20b, 20b having hooks hooked on left and right ends of the plate 20a, respectively. Are hooked on the bottom portion 13e of the frame portion 13. Therefore, for example, when a left steering operation is performed, the centering spring 20b located on the near side in FIG. 4 extends, and a reaction force is generated in the centering spring 20b to return to the original length. The lever 11 will be biased to return to the neutral position. When returning the lever 11 to the neutral position, the reaction force of the centering spring 20b assists the return of the lever 11. The centering mechanism 20 including the centering spring 20b is convenient for the lever 11 to return to the neutral position by itself. However, depending on the situation, a steering instruction not intended by the driver may be given, and the driver may feel uncomfortable. For example, the operation feeling may be different from the self-aligning torque of a normal vehicle.
[0037]
Next, the control device 4 will be described.
The control device 4 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an ECU (Electronic Control Device) including a predetermined electric circuit, as shown in FIG. The operation unit 1 and the steering mechanism unit 2 (the steering motor 5) are electrically connected via a harness which is a signal transmission cable.
[0038]
As shown in FIG. 7, the control device 4 includes a steering control unit 31 that controls the steering motor 5 and an operation reaction force control unit 32 that controls the operation reaction motor 19 of the operation unit 1. I have. The signals handled by the computer-related portion of the control device 4 are all digitized data (control amounts) and information.
[0039]
The turning control unit 31 receives the detection value (operation angle) θs of the operation angle sensor 16 of the operation unit 1 and inputs the detection value (operation angle) θs, and the turning angle of the steered wheels W, W corresponding to the operation amount of the operation unit 1 performed by the driver. A target turning angle setting unit 34 for setting the target value θm of the turning angle, and a deviation amount of the turning angle (a deviation amount signal) from the target value θm of the turning angle and the current actual turning angle (actual turning angle signal θr). Drs), a steering motor control signal output unit 36 for generating an output signal Ds (direction signal + PWM signal) for driving the steering motor 5 in accordance with the deviation amount signal Drs, and the output signal Ds. And a steering motor drive circuit 37 which is an electric circuit for driving the steering motor 5 based on the above.
[0040]
The target turning angle setting unit 34 determines a target turning angle by searching a map using the detection value θs of the operation angle sensor 16 as an address, and outputs a target turning angle signal θm based on the target turning angle. That is, the driving operation device of the vehicle according to the present embodiment basically performs control of the positions (steering angles) of the steered wheels W, W corresponding to the positions (operating angles) of the levers 11.
[0041]
The deviation calculating unit 35 calculates a deviation between the target turning angle signal θm and the current actual turning angle signal θr measured by the turning angle sensor 10. If the deviation amount is a negative value, it is determined that the steering is to the left, and a deviation amount signal Drs having the polarity and magnitude corresponding to each is output.
[0042]
Then, the steering motor control signal output unit 36 calculates a control signal obtained by subjecting the deviation amount signal Drs to P (Proportional), I (Integral), and D (Differential) processing, and calculates a control signal described later. Synthesize with Fcs. Then, a control output signal Ds (direction signal + PWM signal) corresponding to the sign of the composite value and the magnitude of the absolute value is output to the steering motor drive circuit 37. The steering motor control signal output unit 36 has the above-described PID function to improve the followability of the movement of the rack shaft 7 to the target turning angle.
[0043]
Here, the steering control unit 31 sends the control signal Fcs to the steering motor control signal output unit 36 based on the torque detection value Ts of the operation torque sensor 15 of the operation unit 1 in order to improve the initial response in the steering operation. An FF control unit 38 that performs FF control by outputting is provided. Thus, in a state where the operation angle of the lever 11 is small as in the initial stage of the operation, but the torque applied to the lever 11 is large, the rack shaft 7 can be moved prior to the subsequent increase in the operation amount of the lever. Therefore, responsiveness of the steering operation can be improved. Here, the control signal Fcs is determined based on a map of the detected torque value Ts and the drive amount of the steering motor 5 prepared in the FF control unit 38.
[0044]
In addition, the operation reaction force control unit 32 includes a detection value θs of the operation angle sensor 16 of the operation unit 1, a deviation amount signal Drs from the deviation calculation unit 35, and a vehicle speed detection value from the vehicle speed sensor 22 provided outside the operation unit 1. (Hereinafter, abbreviated as “vehicle speed”) a target operation reaction force setting unit 39 that determines a target operation reaction force acting on the lever 11 based on V and the torque detection value Ts of the operation torque sensor 15, and a target operation reaction force setting unit An operation reaction motor control signal output unit 40 that obtains a target operation reaction force signal Tms output from the control signal 39 and outputs a control signal Mcs for driving the operation reaction motor 19, and an operation reaction motor control signal Mcs based on the control signal Mcs. And an operation reaction force motor drive circuit 41 comprising an electric circuit for driving the force motor 19.
[0045]
FIG. 8 shows a detailed functional block of the target operation reaction force setting unit 39. FIG. 9 shows a map of the constant K2 multiplied by the virtual torsion bar control. FIG. 11 shows a processing map in the operation angular velocity map processing section. FIG. 12 shows a processing map in the operation angle map processing unit. FIG. 13 shows a processing map in the vehicle speed map processing section. FIG. 14 shows a processing map in the steering (operation) torque map processing section. FIG. 10 is an explanatory diagram of the arithmetic processing performed in the going-back determination processing unit.
[0046]
The virtual torsion bar map processing unit 51 in FIG. 8 calculates a deviation amount signal Drs between the target turning angle value θm obtained by the deviation calculation unit 35 and the current actual turning angle signal θr as a function of the vehicle speed V K2. Is given as an element of the target operation reaction force signal Tms as virtual torsion bar control. That is, assuming that the output of the virtual torsion bar map processing unit 51 is Cvt, Cvt is given by the following equation (1).
[0047]
Cvt = K2 (V) Drs (1)
[0048]
The virtual torsion bar control is a control that generates a reaction force as if a steer-by-wire vehicle has a torsion bar (steering shaft). As shown in FIG. 9, the constant K2 is set to a large value when the vehicle speed V is large and a small value when the vehicle speed V is small in order to reduce the operating force at low speeds and to stabilize the vehicle at high speeds. .
[0049]
The going-back determination processing unit 52 performs an arithmetic process as shown in FIG. That is, when the differential value of the absolute value | θs | of the detection value θs of the operation angle sensor 16 is negative, the return is performed, and when the differential value is positive, the return is determined to be going. And outputs a return determination signal Dgb. This determination is sent to the return operation selection unit 60 and used for selecting the reaction force at the time of return. Since the operation torque is not used in this determination, the sign does not change due to the change in the value of the operation torque, and it is possible to stably determine the forward and return. The back-and-forth return processing unit 52 corresponds to “back and back determination means” in the claims.
[0050]
The operation angular velocity calculator 53 differentiates the detection value θs of the operation angle sensor 16 to obtain the operation angular velocity Srv, and sends the obtained operation angular velocity Srv to the operation angular velocity map processor 54. The operation angular velocity map processor 54 performs a map search using the operation angular velocity Srv as an address to obtain an output Crv. That is, the conversion processing represented by the following equation (2) is performed.
[0051]
Crv = f1 (Srv) (2)
[0052]
The “operation amount change speed detection means” in the claims corresponds to the operation angular velocity calculation unit 53, and the “operation amount change speed responsive reaction force adjustment means” corresponds to the operation angular velocity map processing unit 54.
[0053]
Here, as shown in FIG. 11, the operation angular velocity map f1 (Srv) reduces the control amount as the operation angular velocity Srv increases, and returns when the driver is in a hurry to return the operation unit 1. Respect the driver's intention by reducing the reaction force. This output Crv is gain-adjusted (amplification coefficient k) by the amplifier 55 and is input to the reaction force element multiplication product operation unit 59.
[0054]
The operation angle map processing section 56 performs a map search using the detection value θs of the operation angle sensor 16 as an address to obtain an output Crs. That is, the conversion processing represented by the following equation (3) is performed.
[0055]
Crs = f2 (θs) (3)
[0056]
Here, the operation angle map f2 (θs) decreases as the operation center (the neutral position of the lever 11) approaches the operation center in order to eliminate uncomfortable feeling at the time of turning back. Further, when it is desired to make the return reaction force effective when the detection value (operation angle) θs is large, for example, when turning around an intersection, the control amount is increased as the operation angle signal θs increases (see FIG. 12).
The "operation amount responsive reaction force adjusting means" in the claims corresponds to the operation angle map processing unit 56.
[0057]
The vehicle speed map processing unit 57 performs a map search using the detection value V of the vehicle speed sensor 22 as an address to obtain an output Cv. That is, the conversion processing represented by the following equation (4) is performed.
[0058]
Cv = f3 (V) (4)
[0059]
Here, the vehicle speed map f3 (V) obtains a large reaction force on the low vehicle speed side as shown in FIG. As a result, the return reaction force can be effectively exerted at a low vehicle speed such as when turning around an intersection.
The “vehicle speed responsive reaction force adjusting means” in the claims corresponds to the vehicle speed map processing unit 57.
[0060]
The operation torque map processor 58 performs a map search using the detection value Ts of the operation torque sensor 15 as an address to obtain an output Cts. That is, the conversion processing represented by the following equation (5) is performed.
[0061]
Cts = f4 (Ts) (5)
[0062]
As shown in FIG. 14, the operation (steering) torque map f4 (Ts) reduces the control amount when the torque is large, and respects the driver's intention similarly to the operation angular velocity map. I have.
The "torque response reaction force adjusting means" in the claims corresponds to the operation torque map processing unit 58.
[0063]
Each element that gives a return reaction force at the time of these return operations is all multiplied by the reaction element multiplication product operation unit 59, and the resulting product Pt is input to the return reaction force selection unit 60. Note that the product of multiplication Pt is represented by the following equation (6).
[0064]
Pt = kCrv · Crs · Cv · Cts (6)
[0065]
The return reaction force selection unit 60 selects the product of multiplication Pt output from the reaction force element multiplication product calculation unit 59 only when the return determination signal Dgb output from the return determination processing unit 52 is “0”, that is, return. I do. The output Ptb of the return reaction force selection unit 60 is added to the output Cvt of the virtual torsion bar map processing unit 51 by an adder 61, and the output is obtained as a target operation reaction force signal Tms output from the target operation reaction force setting unit 39. The operation reaction force motor control signal output unit 40 inputs the operation reaction force motor 19 to determine the direction and magnitude of the operation reaction force generated by the operation reaction force motor 19, and this operation reaction force is added to the force from the centering mechanism 20 to perform operation. Is applied as a reaction force to the lever 11 of the operation unit 1 operated by the user. The return reaction force selection unit 60 corresponds to “reaction force control means” in the claims.
[0066]
Next, the operation of the vehicle equipped with the control device 4 will be described with reference to FIGS.
First, when the driver steers the lever 11 rightward from the neutral position, the amount of operation of the lever 11 is small, but the torque applied to the lever 11 is large in the initial stage of the operation. Here, since the detected torque value Ts (positive output value) from the operation torque sensor 15 is output, the FF control unit 38 of the turning control unit 31 searches the torque map using the detected torque value Ts as an address to perform steering. The control signal Fcs input to the motor control signal output unit 36 is determined. Then, based on this control signal Fcs, the rack shaft 7 linearly moves, and the rack shaft 7 starts to move to the right before the full-scale operation of the lever 11.
[0067]
Then, based on the operation angle of the lever 11 (detected value θs), the control device 4 sets the target turning angle signal θm, and the deviation amount of the current actual turning angle signal θr from the target turning angle signal θm ( The deviation amount signal Drs) is calculated. Then, the steering motor control signal output unit 36 and the steering motor drive circuit 37 operate based on the deviation amount signal Drs to drive the steering motor 5 to move the rack shaft to the right by a predetermined amount. On the other hand, the operation reaction force control unit 32 of the control device 4 sets the operation reaction force to be applied to the lever 11 in accordance with the deviation amount signal Drs, drives the operation reaction force motor 19, and turns the lever 11 to the left. Then, an operation reaction force corresponding to the target operation reaction force signal Tms composed of the output Cvt of the virtual torsion bar map processing unit 51 is generated. This reaction force is applied to the lever 11 to the left together with a reaction force proportional to the operation angle signal θs given by the centering mechanism 20.
[0068]
In this state, when the lever 11 is further operated to the right, the steering reaction force to the left increases and the steering angle further increases to the right. On the other hand, when the lever 11 is operated to the left from this point, the turning angle decreases and the force from the centering mechanism 20 acts on the lever 11 to the left as an assist force. On the other hand, the operation reaction force control unit 32 of the control device 4 calculates the reaction force element product product calculation unit 59 → the output Ptb of the return reaction force selection unit 60 (see FIG. 8) and the sum of the output Cvt of the virtual torsion bar map processing unit 51. An operation reaction force Ms corresponding to the target operation reaction force signal Tms is set, and the operation reaction force is applied to the lever 11 to the right by the operation reaction motor 19 corresponding to the operation reaction force Ms.
[0069]
Next, a case where the driver operates the lever 11 to the left from the neutral position will be described.
Since the torque output value Ts from the operation torque sensor 15 of the operation unit 1 is output in the initial stage of the operation in the same manner as described above, the FF control unit 38 of the steering control unit 31 uses the torque output value Ts as an address for the torque map. To determine the control signal Fcs input to the steering motor control signal output unit 36. Then, based on the control signal Fcs, the rack shaft 7 linearly moves, and the rack shaft 7 starts to move to the left before the full-scale operation of the lever 11. Since the FF control is performed based on the torque as described above, a quick response can be obtained.
[0070]
Then, based on the operation amount of the lever 11, the control device 4 sets the target turning angle signal θm, and calculates a deviation signal Drs of the current actual turning angle signal θr from the target turning angle signal θm. Then, the steering motor control signal output unit 36 and the steering motor drive circuit 37 operate to drive the steering motor 5 based on the deviation amount signal Drs, and the rack shaft 7 moves to the left by a predetermined amount. On the other hand, the operation reaction force control unit 32 of the control device 4 sets an operation reaction force according to the deviation amount applied to the lever 11, drives the operation reaction force motor 19, and causes the lever 11 to move the virtual torsion bar map rightward. An operation reaction force corresponding to the target operation reaction signal Tms composed of the output Cvt of the processing unit 51 is generated, and this reaction force is applied to the lever 11 rightward together with a reaction force proportional to the operation angle signal θs given by the centering mechanism 20. .
[0071]
In this state, when the lever 11 is further operated to the left, the rightward reaction force increases, and the steering angle further increases to the left. On the other hand, when the lever 11 is operated rightward from this state, the steering angle decreases and the force from the centering mechanism 20 acts on the lever 11 to the right as an assist force. On the other hand, the operation reaction force control unit 32 of the control device 4 calculates the target operation reaction force which is the sum of the reaction force element product product calculation unit 59 → the output Ptb of the return reaction force selection unit 60 and the output Cvt of the virtual torsion bar map processing unit 51 An operation reaction force Ms is set in accordance with the signal Tms, and the operation reaction force is applied to the lever 11 to the left by the operation reaction motor 19 in accordance with the operation reaction force Ms.
[0072]
As described above, in the steering operation, when the steering operation is returned, the reaction force is applied to the lever 11 of the operation unit 1 with an optimal setting corresponding to the vehicle speed, the operation angle, the operation angular speed, and the operation torque. In general, the self-aligning torque close to the self-aligning torque of a normal vehicle can be obtained, and there is no uncomfortable feeling in the operation, and the operability of the turning operation can be improved.
[0073]
That is, when the return operation is determined, the reaction force is increased when the vehicle speed is low (see FIG. 13), so that unnecessary return to the neutral position of the lever 11 is restricted, and the self-aligning torque of the normal vehicle is restricted. An operation feeling close to is obtained. It is to be noted that the driver is likely to feel uncomfortable at low vehicle speeds and at medium vehicle speeds. When the return operation is determined, if the operation angle is large, the reaction force is increased (see FIG. 12), so that unnecessary return to the neutral position of the lever 11 is restricted, and self-alignment of a normal vehicle is performed. An operation feeling close to the torque can be obtained.
[0074]
On the other hand, when the return operation is determined, if the change speed of the operation angle (operation angular speed) is large, the reaction force is reduced (see FIG. 11), so that the operation of the lever 11 according to the driver's intention can be performed. it can. When the return operation is determined, the reaction force is reduced when the operation torque is large (see FIG. 14), so that the operation of the lever 11 according to the driver's intention can be performed.
[0075]
In other words, according to the present invention, the lever 11 returns in accordance with the return speed of the steered wheels W, W, not only in a normal case, but also, for example, when the vehicle turns a right angle at an intersection. Smooth operation can be performed as shown in a portion surrounded by a broken line. On the other hand, when the control of the present invention is not performed, as shown in a portion surrounded by a broken line in FIG. 2A as a comparative example, the lever 11 is quickly moved to the neutral position due to the influence of the centering mechanism 20 (centering spring 20b). Therefore, the operation is jerky to correct this (the driver performs the operation of returning the steering angle in FIG. 2A). In addition, even if the road surface condition changes, the reaction force (return of the lever 11) takes into account the return condition of the steered wheels W, W, and the driver can feel the road surface condition accurately although it is simulated.
[0076]
The present invention described above can be widely modified without being limited to the above-described embodiment of the invention.
For example, the operation unit operated by the driver is described using a lever (joystick) as an example, but this may be a normal steering wheel. Although only the steering is performed by the lever, the throttle operation and the brake operation may be performed by the same lever. Further, the control device can be configured as software or hardware. Further, the reaction force control means applies an operation reaction force to the lever according to a deviation between the operation amount (target steering angle) and the actual steering amount (steering angle). May be applied (the ratio can be regarded as one mode of the deviation).
[0077]
【The invention's effect】
According to the invention of claim 1 of the present invention, a going operation and a returning operation of the operation unit are distinguished, and the reaction force is increased at the time of the returning operation. As a result, an operation feeling close to the self-aligning torque of a normal vehicle is obtained, and there is no uncomfortable feeling in the operation, and the operability of the steering operation can be improved.
[0078]
According to the invention of claim 2 of the present invention, the determination of the going operation and the returning operation is performed based on the positive / negative determination of the differential value of the absolute value of the operation angle detection value. Thus, the going operation and the returning operation can be accurately determined.
[0079]
In the invention of claim 3 of the present invention, the reaction force is small when the change speed of the operation angle is large, and is large when the change speed is small. Thus, when the driver wants to return the steered wheels quickly, the reaction force can be reduced and the reaction force control can be performed with the driver's intention in mind.
[0080]
According to the invention of claim 4 of the present invention, the reaction force is large when the vehicle speed is low, and is small when the vehicle speed is high. This makes it possible to increase the reaction force at low speeds, such as after turning around an intersection, to simulate an operation feeling close to the self-aligning torque of a normal vehicle.
[0081]
In the invention of claim 5 of the present invention, the reaction force is increased when the operation angle is large, and reduced when the operation angle is small. As a result, it is possible to eliminate a sense of incongruity in the operation at the time of switching from “return to going” (the switching can be smoothly performed). Further, the reaction force is increased by the return after the operation angle is greatly reduced, such as after turning at an intersection, so that an operation feeling close to the self-aligning torque of a normal vehicle can be obtained in a pseudo manner.
[0082]
According to the invention of claim 6 of the present invention, the reaction force is reduced when the operation torque is large, and is increased when the operation torque is small. Thus, when the driver wants to return the steered wheels quickly, the reaction force can be reduced and the reaction force control can be performed with the driver's intention in mind.
[Brief description of the drawings]
FIG. 1 is a reaction force function block diagram of a vehicle driving operation device according to an embodiment of the present invention.
FIG. 2 is a comparison diagram of reaction force control data of the embodiment according to the present invention and conventional data.
FIG. 3 is an overall configuration diagram of a vehicle driving operation device according to the embodiment of the present invention.
FIG. 4 is a perspective view showing a form of an operation unit of the vehicle driving operation device according to the embodiment of the present invention.
FIG. 5 is a graph showing output characteristics of the operation torque sensor of the embodiment according to the present invention.
FIG. 6 is a graph showing output characteristics of the operation angle sensor of the embodiment according to the present invention.
FIG. 7 is a block diagram for explaining data processing performed in the vehicle driving operation device according to the embodiment of the present invention.
FIG. 8 is a detailed functional block diagram of a target operation reaction force setting unit according to the embodiment of the present invention.
FIG. 9 is a diagram showing a map of a constant K2 multiplied by virtual torsion bar control according to the embodiment of the present invention.
FIG. 10 is an explanatory diagram of a calculation process performed in a return determination processing unit according to the embodiment of the present invention.
FIG. 11 is a diagram showing a processing map in an operation angular velocity map processing unit of the embodiment according to the present invention.
FIG. 12 is a diagram showing a processing map in an operation angle map processing unit of the embodiment according to the present invention.
FIG. 13 is a diagram showing a processing map in a vehicle speed map processing unit of the embodiment according to the present invention.
FIG. 14 is a diagram showing a processing map in an operation (steering) torque map processing unit of the embodiment according to the present invention.
[Description of Signs] 1 ... operation unit, 2 ... steering mechanism, 4 ... control device, 5 ... steering motor, 6 ... gear box, 7 ... rack shaft, 8 ... tie lot, 9 ... ball screw mechanism, 10 ... steering Angle sensor, 11 ... Lever, 12 ... Operation amount detecting means, 14, 24 ... Rod, 15 ... Operation torque sensor, 16 ... Operation angle sensor, 17 ... Pulley, 18 ... Belt, 19 ... Operation reaction force motor, 20 ... Centering Mechanism 22, vehicle speed sensor 31, turning control unit 32, operation reaction force control unit 34, target turning angle setting unit 35, deviation calculation unit 36, steering motor control signal output unit 37, steering motor Drive circuit, 38: FF control unit, 39: target operation reaction force setting unit, 40: operation reaction force motor control signal output unit, 41: operation reaction force motor drive circuit, 51: virtual torsion bar map processing unit, 52 Backward / backward determination processing unit, 53: operation angular velocity calculation unit, 54: operation angular velocity map processing unit, 55: amplifier, 56: operation angle map processing unit, 57: vehicle speed map processing unit, 58: operation torque map processing unit, 59 ... Reaction product multiplication product calculation unit, 60 ... return reaction selection unit, 61 ... Adder

Claims (6)

An operation unit operated by a driver, operation amount detection means for detecting an operation amount of the operation unit, and control for controlling an actual turning amount of the steered wheels based on at least the operation amount detected by the operation amount detection means Means, a centering spring that returns the operation unit to the neutral position, and a reaction force applying unit that applies an operation reaction force to the operation unit in an operation direction.
Back and forth determining means for determining a going operation and a returning operation of the operation of the operation unit; and a reaction force given by the reaction force applying means when the going and returning determining means determines the returning operation, as compared with the time of the going operation. A driving operation device for a vehicle, comprising: a reaction force control unit for increasing the reaction force. 2. The driving operation device for a vehicle according to claim 1, wherein the going-back determining means determines the going operation and the returning operation from the positive or negative of the differential value of the absolute value of the operation amount detection value of the operation amount detecting means. An operation amount change speed detecting unit that detects a change speed of the operation amount; the reaction force control unit detects a reaction force to be controlled when the operation amount change speed detection unit detects a large change speed of the operation amount; 2. The driving operation device for a vehicle according to claim 1, further comprising an operation amount change speed responsive reaction force adjusting unit that increases when the change speed is small and the change speed is small. Vehicle speed detecting means for detecting a vehicle speed, wherein the reaction force controlling means increases the reaction force to be controlled when the vehicle speed detected by the vehicle speed detecting means is low and decreases when the vehicle speed is high; The driving operation device for a vehicle according to claim 1, comprising: The reaction force control means may include an operation amount responsive reaction force adjustment means for increasing a control force to be controlled when the operation amount of the operation unit detected by the operation amount detection means is large, and decreasing the reaction force when the operation amount is small. The driving operation device for a vehicle according to claim 1 or 4, wherein: A torque-responsive reaction force for controlling the reaction force to be small when the operation torque is large and large when the operation torque is small; The vehicle operating device according to claim 1, further comprising an adjusting unit.

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