JP4283200B2 - Vehicle steering control device - Google Patents

Description

  The present invention relates to a steering control device for a vehicle that can automatically steer wheels during parking.

  Developed as a steering control device that automatically performs the steering operation during parking, an actuator such as an electric motor is added to the steering mechanism that steers the wheels, and the actuator is controlled according to a program stored in advance. (For example, refer to Patent Document 1).

In this conventional steering control device, the relationship between the relative position change amount from the reference position (for example, the garage entry start position) and the posture angle of the vehicle is stored in advance in the form of a map, and while moving from the reference position to the target position, Further, the actuator is controlled so as to reduce the deviation between the reference posture angle obtained by referring to the map and the actual posture angle (actual posture angle). Further, in this apparatus, a turning angle sensor for detecting the turning angle of the wheel is provided, and the actual posture angle is calculated based on the turning angle detected by the turning angle sensor. Yes.
Japanese Patent No. 3266828

  However, in the case of this steering control device, the reference attitude angle corresponding to the amount of movement of the vehicle is stored in the form of a map, and the steering actuator is controlled so that the actual attitude angle approaches the reference attitude angle. The memory capacity for storing the reference attitude angle in advance must be increased. In particular, when a plurality of types of garage storage patterns such as parallel parking and parallel parking (each left and right) are set, the required memory capacity becomes considerably large and the cost becomes high.

  Therefore, the present invention makes it possible to reliably move the vehicle from the reference position to the target position without storing data of the reference posture angle corresponding to the amount of movement of the vehicle, and to reduce the memory capacity. An object of the present invention is to provide a vehicle steering control device.

In order to achieve the above object, the invention described in claim 1 is directed to a steering mechanism that steers wheels (for example, a steering mechanism 3 in an embodiment described later) and an actuator that drives the steering mechanism (for example, The electric motor 4 in the embodiment described later) and the vehicle from the reference position (for example, the parking reference position (1) in the embodiment described later) to the target position (for example, the first target position (2) in the embodiment described later). In the vehicle steering control device, which includes a control unit (for example, a control unit 34 in an embodiment described later) that controls the actuator when moving to), a change in geomagnetism corresponding to the attitude angle of the vehicle is detected. geomagnetic sensor (e.g., geomagnetic sensor 20 in the embodiment) and the wheel speed sensor for detecting a wheel speed of the vehicle (e.g., wheel speed sensor 1 will be described in the exemplary embodiment ) And the geomagnetic sensor and receives an output signal from the wheel speed sensors, the relative position detection for detecting a relative position from a reference position of the vehicle by the two perpendicular axial component of displacement of the vehicle respectively accumulating means (e.g., relative position detecting unit 31 in the embodiment) and the vehicle state at the target position, the target vehicle state setting means for setting a geomagnetic variation and the relative position change amount from the reference position (for example, later a target vehicle state setting means 30) in the embodiment of the reference position and the target position path regulating means for defining a movement path of the vehicle connecting (e.g., a path defining means 32) will be described in the exemplary embodiment, the provided, the control means, when the vehicle is actually moved to the target position from the reference position, along the movement path of the vehicle is defined by the path defining means and, at the target position And the steering actuator is controlled so that the amount of change in geomagnetism and the amount of relative position change set by the target vehicle state setting means, and when the vehicle rides on the movement path before the target position, The steered actuator is controlled to maintain the geomagnetic change amount set by the target vehicle state setting means.

In the case of this invention, when the vehicle is parked, first, the geomagnetic change amount and the relative position change amount are set by the target vehicle state setting means, and the movement route connecting the reference position and the target position is specified by the route specifying means. Then, when the vehicle actually moves, the actuator follows the moving path defined by the vehicle and finally becomes the geomagnetic change amount and the relative position change amount set by the target vehicle state setting means. It is controlled by the control means. Further, when the vehicle rides on the moving path before the target position, the actuator is controlled by the control means so as to maintain the geomagnetic change amount set by the target vehicle state setting means. Therefore, what is called from the memory at the time of setting the target vehicle state or obtained by calculation based on the memory value is the value of the geomagnetic change amount and the relative position change amount when the vehicle reaches the target position.

According to a second aspect of the present invention, in the first aspect of the present invention, in the first aspect of the present invention, obstacle detection means for detecting an object that becomes an obstacle when the vehicle moves from the reference position to the target position (for example, an obstacle in an embodiment described later) Detection means 13) is provided, and when the obstacle detection means detects an object that becomes an obstacle, the actuator is controlled by the control means so as to avoid the object.

  In this case, when an object that becomes an obstacle is detected by the obstacle detection means while the vehicle moves toward the target position, the actuator is controlled so as to avoid the object. If there is no problem after avoiding this object, the previous control toward the target vehicle state is continued. However, since the final target vehicle state does not change at this time, the vehicle moves until the target state is reached. It becomes possible to make it.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a posture angle change limiting means for limiting a posture angle change amount of the vehicle during control (for example, a posture angle change amount in an embodiment described later). A limiting means 33) is provided.

  In this case, since a sudden change in posture of the vehicle is restricted by the posture angle change amount limiting means, a sudden change in posture angle is prevented. Also, when the vehicle tries to move in a different direction due to some error, the posture angle change amount of the vehicle is limited by the posture angle change amount limiting means. Accordingly, unnecessary detour travel of the vehicle is prevented.

According to the first aspect of the present invention, when the vehicle actually moves from the reference position to the target position , the control means follows the movement route defined by the route defining means, and at the target position, the target vehicle state The steering actuator is controlled so that the amount of change in geomagnetism set by the setting means and the amount of relative position change are set, and the geomagnetism set by the target vehicle state setting means when the vehicle gets on the moving path before the target position. Since the steering actuator is controlled so as to maintain the change amount , the vehicle can be reliably moved to the target position without storing the reference posture angle data according to the movement amount of the vehicle one by one. Therefore, according to the present invention, the amount of data stored in the memory in advance is reduced, so that the mounted memory capacity can be reduced.

  The invention according to claim 1 is a conventional type in which the attitude angle of the vehicle is inferred from the steering angle, the turning angle of the wheels, etc., because the attitude angle of the vehicle at the time of automatic steering is directly detected by a geomagnetic sensor. Unlike things, it is not affected by changes in external factors. Therefore, according to the present invention, accurate steering control can always be realized.

According to the first aspect of the present invention, when the vehicle actually moves from the reference position to the target position , the control means follows the movement route specified by the route specifying means, and at the target position. The steering actuator is controlled so that the amount of change in geomagnetism and the amount of relative position change set by the target vehicle state setting means, and the target vehicle state setting means when the vehicle gets on the moving path before the target position Because the steering actuator is controlled to maintain the geomagnetic change amount set in step 1, the actuator can be easily controlled and the trajectory can be easily corrected when the vehicle temporarily moves in a different direction for some reason. An effect is obtained.

According to the second aspect of the invention, even if there is an object that becomes an obstacle while the vehicle moves toward the target position, the obstacle can be smoothly avoided by controlling the actuator. In this case, the steering control can be continued without any trouble. Accordingly, since the possibility of stopping the steering control is reduced, the convenience for the driver is enhanced.

According to the third aspect of the present invention, it is possible to prevent the vehicle from making unnecessary detours by means of the posture angle change amount limiting means, so that it is possible to realize a travel without waste for the driver.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. To facilitate understanding of the embodiment, a reference example shown in FIGS. 6 to 15 similar to the embodiment will be described first. In the embodiment described later, the same parts as those in the reference example are denoted by the same reference numerals.

  FIG. 6 is a schematic configuration diagram of a vehicle 100 according to a reference example, where Wf and Wr are front and rear wheels of the vehicle, and 1 is a steering wheel. The steering wheel 1 is linked to the left and right front wheels Wf via a steering shaft 2 and a steering mechanism 3 including a gear mechanism, a tie rod, and the like. The steering mechanism 3 is an actuator that drives the mechanism 3. An electric motor 4 is attached. Further, the steering shaft 2 is provided with a torque sensor 5 for detecting a steering torque by a driver. The torque sensor 5 constitutes an electric power steering together with the electric motor 4. The electric motor 4 is controlled by a controller (electronic control unit) 6 and basically functions as a drive source for electric power steering. However, the drive source of a steering control device that performs automatic steering during parking by switching by a switch operation described later. Also works. Also in this case, the electric motor 4 is controlled by the same controller 6.

  In addition to the torque sensor 5 being connected to the input side of the controller 6, the shift range selected by the shift lever ("D" range, "R" range, "N" range, "P" range, etc.) ) Is detected, and a brake switch 8 or the like linked to whether or not the brake is depressed is connected. On the other hand, on the output side, in addition to the electric motor 4, the driver's operation is performed by voice guidance. A voice teaching speaker 9 is connected to assist the driver or to alert the driver. Further, the controller 6 is connected to a wiring of an operation panel 11 which will be described later, in which a monitor 10 is integrated, and to a power switch 12 of an automatic steering system. The power switch 12 also functions as an emergency stop switch during automatic steering.

  Although wiring is omitted in the figure, on the input side of the controller 6, a wheel speed sensor 19 for detecting the rotational speeds of the front and rear wheels Wf and Wr and obstacles during traveling are arranged on both the front and rear sides of the vehicle. Is connected to an obstacle detection means 13 for detecting the image of the vehicle with an ultrasonic wave, a radar or the like, and an imaging means 14 for taking images of the front and rear of the vehicle.

  On the operation panel 11, as shown in FIG. 7, in addition to the monitor 10, mode selection switches 15a to 15d for setting a parking mode (left / right rear side parallel parking mode and parallel parking mode), and a start for starting automatic steering. A switch 16, a warning lamp 17, a buzzer 18, and the like are provided, and the driver's intention to operate is reflected on the controller 6 by a switch operation, and the state and control state of the vehicle 100 are driven by the monitor 10, the warning lamp 17, the buzzer 18, etc. To inform the person.

  The vehicle 100 is equipped with a geomagnetic sensor 20 that detects a change in geomagnetism as viewed from the vehicle 100. The geomagnetic sensor 20 is used for detecting the azimuth on the ground by geomagnetism and determining the attitude angle of the vehicle (the horizontal direction of the vehicle) with respect to the azimuth. The geomagnetic sensor 20 is connected to an internal circuit of the controller 6, and the controller 6 obtains the current attitude angle of the vehicle 100 based on the detection value of the sensor 20.

  As shown in FIG. 8, the geomagnetic sensor 20 has an axis of a sensor detection portion (amorphous wire or the like) on the central axis (axis passing through the center in the vehicle width direction) o of the vehicle 100 or parallel to the central axis o. It is desirable that the geomagnetic sensor 20 be offset so that the axis of the detection unit is inclined at a set angle (θ in the figure) with respect to the center axis o of the vehicle 100, and the attitude angle is determined. The offset may be corrected by calculation.

In the vehicle 100 of this reference example, as shown in FIG. 9, a geomagnetic sensor 20 having two orthogonal detection units 20 a and 20 b is used, so that the detection accuracy for a geomagnetism and the detection performance against a failure can be improved. Yes. Further, in this vehicle 100, the geomagnetic sensor 20 is integrated with the controller 6. The detection unit of the geomagnetic sensor 20 is not limited to two axes, but 3
It may be more than the axis.

  In the storage unit 6a of the controller 6, there are data of attitude angle change amounts corresponding to the moving distance of the vehicle 100 for each of four types of parking modes (left / right rear side parallel parking mode and left / right parallel parking mode). It is stored in the form of a map, and these are read out as needed during automatic control.

  10 and 11 show the standard behavior of the vehicle in the rear side parallel parking on the left side. For example, in this left side parallel parking, the vehicle 100 is moved from the parking reference position of (1) to the final parking position of (3 ′) through the folding position of (2 ′). The map referred to by the control unit is as shown in FIG. The parking reference position (1) is a position close to the parking frame 21 where the center G of the vehicle 100 is positioned on the center line of the parking frame 21 in a posture in which the vehicle 100 is orthogonal to the parking frame 21. Say.

  Here, the map of FIG. 12 will be described. This map is a plot of the attitude angle corresponding to the moving distance of the vehicle 100 from the parking reference position (1), from the parking reference position (1) to the final parking position ( The characteristic line connecting the plot points up to 3 ′) means the following vehicle behavior.

That is, when the vehicle starts to move forward based on the posture angle of the parking reference position (1), the posture angle increases rightward at a substantially constant rate for a while, and the first target position (2) The posture angle change amount is maintained at θ1 until the posture angle change amount reaches θ1 and reaches the folding position (2 ′) as it is. When the vehicle starts to move backward from the turn-back position (2 ′), the posture angle change amount is maintained at θ1 until the first target position (2) is reached, and then the posture angle increases to the right. At this time, since the traveling direction of the vehicle is backward, the rotation direction of the steering wheel 1 is counterclockwise as shown in Table 1. Thereafter, the posture angle change amount reaches θ2 just before the second target position (3), and the posture angle change amount is maintained at θ2 until it reaches the final parking position (3 ′).

  The geomagnetic reference control posture angle when actually parking is obtained by adding the reference posture angle α at the parking reference position (1) to the posture angle change amounts θ1 and θ2 shown in the map of FIG. Become.

  On the other hand, when automatic steering is started at the time of parking, the controller 6 calls a map corresponding to the selected parking mode from the storage unit 6a, and the attitude angle when the vehicle 100 moves is always a map (converted to a geomagnetic reference). The output of the electric motor 4 is controlled so as to approach the value. Specifically, the controller 6 constantly detects the movement distance and posture angle of the vehicle 100 from the parking reference position (1), and maps the target posture angle (control posture angle) according to the movement distance at that time to a map value. And the output of the electric motor 4 is controlled by PID control or the like so that the deviation between the target posture angle and the actual posture angle becomes zero. Here, the moving distance of the vehicle 100 from the parking reference position (1) is obtained by the product of the known circumference of the front wheel Wf and the rotation angle detected by the wheel speed sensor 19, and the actual posture angle is determined by the geomagnetic sensor 20. Obtained based on the detected value.

  Next, the operation when automatic steering is performed at the time of parking will be described taking the left side rear side parallel parking as an example.

  First, the driver directly operates the steering wheel 1 to move the vehicle 100 to the parking reference position (1) while performing visual confirmation. Therefore, the driver once stops the vehicle 100, selects the left side parallel parking mode among the mode selection switches 15a to 15d on the operation panel 11, and then presses the start switch 16, the start switch 16 is turned on. Automatic steering is started.

  When automatic steering is started, a predetermined map is read in the controller 6, and the electric motor 4 is controlled so that the vehicle is always steered to the target posture angle.

  Initially, the vehicle 100 moves forward while changing the posture angle to the right as shown in FIG. 10 by releasing the depression of the brake pedal or by an accelerator operation, and before reaching the first target position (2), the vehicle 100 Is steered so that the attitude angle is maintained at θ1. When the controller 6 determines that the vehicle 100 has passed the first target position (2) and the moving distance of the vehicle 100 from the parking reference position (1) has exceeded R, the display and sound on the monitor 10 are displayed. The driver is informed that the vehicle 100 should be stopped by an instruction from the teaching speaker 9. Thus, when the driver depresses the brake pedal and the vehicle 100 stops at the turn-back position (2 ′), the driver is informed that the shift range should be switched to R by an instruction from the voice teaching speaker 9.

  Thereafter, when the driver switches the shift range to R, gradually releases the brake pedal, and performs an accelerator operation as necessary, the vehicle 100 maintains the posture angle at θ1 and the first target position (2). The vehicle is steered so as to change the posture angle to the right when the first target position (2) is passed. Thus, when the vehicle 100 continues to move backward and the posture angle reaches θ2 before reaching the second target position (3), the posture angle is maintained as it is. When the controller 6 determines that the vehicle 100 has passed the second target position (3) and the moving distance from the first target position (2) has exceeded R ′, the display on the monitor 10 is again performed. In response to the instruction from the voice teaching speaker 9, the driver is informed that the vehicle should be stopped. When the driver depresses the brake pedal according to this instruction, the vehicle stops at the final parking position (3 ′).

  In the above, the left rear side parallel parking has been described as an example, but the parallel parking is as shown in FIGS.

  FIGS. 13 and 14 show the standard behavior of the vehicle in the left side parallel parking, and FIG. 15 is a map similar to FIG. 12 recorded in the controller 6 to obtain this standard behavior. Also in the case of this parallel parking, the control of the electric motor 4 by the controller 6 is basically executed in the same way as in the parallel parking described above, but the map value referred to by the controller 6 is different from that in the parallel parking.

  The map shown in FIG. 15 will be described. The normative behavior at the time of advancing from the parking reference position (1) to the turn-back position (2 ′) is the same as in the case of parallel parking, and from the turn-back position (2 ′) to the final parking position ( The normative behavior up to 3 ′) is as follows. That is, after the posture angle is maintained at θ1 for a predetermined distance beyond the first target position (2), the posture angle continues to change to the left (the steering wheel 1 rotates to the right), and the second target When the posture angle returns to the reference posture angle before the position (2), the posture angle is maintained until the final parking position (3 ′).

  Therefore, also in the case of this parallel parking, the vehicle 100 is reliably guided in the parking frame 21 by controlling the posture angle so as to follow the map shown in FIG.

  Next, an embodiment of the present invention based on the above reference example will be described with reference to FIGS. Since the vehicle 200 of this embodiment has almost the same configuration as the vehicle 100 of the reference example described above except for the internal function of the controller 206, FIG. 6 and FIG. 7 are commonly used to show this embodiment. In FIG. 6, the reference numerals of the vehicle 200 and the controller 206 are shown in parentheses. Moreover, since it becomes the description which overlaps with a reference example about the whole structure of the vehicle 200, detailed description shall be abbreviate | omitted below.

  In the vehicle steering control device of this embodiment, data corresponding to the parking mode (see FIG. 7) is stored in the storage unit 6a in the controller 206 as in the reference example. The electric motor 4 is controlled. However, in the steering control device of this embodiment, the data stored in the controller 206 and the processing function unit configured in the controller 206 are greatly different from those in the reference example.

  The data stored in the storage unit 6a is not the data of the posture angle corresponding to the moving distance of the vehicle 200, but the vehicle state when changing from the vehicle state at the reference position to the reference posture state at the target position. The change amount is stored as the geomagnetic change amount and the relative position change amount.

  For example, now considering the left rear side parallel parking shown in FIGS. 2 to 4, the vehicle state when the vehicle is at the parking reference position (1) is the reference vehicle state, and the vehicle 200 is the target at the first target position (2). Is the reference vehicle state, the geomagnetic change amount θ1 and the relative position change amount (−x1, + y1) are stored in the storage unit 6a as the change amount of the vehicle state during this period. Yes. However, the xy coordinates in FIGS. 2 to 4 pass through the center axis of the vehicle (the axis passing through the center in the vehicle width direction) when the vehicle 200 is at the parking reference position (1), and the right side in the figure is positive. The axis is the x-axis, and the axis orthogonal to the x-axis and having the upper side in the figure as the positive is the y-axis.

  The geomagnetic change amount θ1 and the relative position change amount (−x1, + y1) described above are forward data for guiding the vehicle 200 from the parking reference position (1) to the first target position (2). However, in the storage unit 6a, the geomagnetic change amount θ2 and the relative position change are separately stored as data for reversing the vehicle from the first target position (2) to the second target position (3). The quantity (0, -y1) is stored. Note that the geomagnetic change amount θ2 and the relative position change amount (0, −y1) are calculated by calculating in the controller 6a when the vehicle state at the first target position (2) is set as the reference vehicle state. And the data value converted from the coordinate center. In this case, the geomagnetic change amount is θ2−θ1, and the relative position change amount is (+ x1, −2y).

  In this embodiment, the portion for calling and calculating the data in the controller 6a constitutes the target vehicle state setting means 30 in the present invention (see FIG. 1).

  As shown in FIG. 1, the processing function unit in the controller 6a includes a target vehicle state setting unit 30, a relative position detection unit 31 for obtaining a relative position of the actual vehicle 200 with respect to a reference position, and a target vehicle state setting unit. A route defining means 32 for defining the moving path of the vehicle based on the relative position change amount set in 30, a posture angle change amount limiting means 33 for limiting the maximum change amount of the posture angle per moving distance of the vehicle 200, and the like. Control means 34 for controlling the electric motor 4 based on the output value from the means and the output value of the geomagnetic sensor 20.

The relative position detecting means 31 receives the output signals from the geomagnetic sensor 20 and the wheel speed sensor 19, and obtains the relative position of the vehicle 200 with respect to the reference position by cumulatively adding the X-axis component and the y-axis component of the vehicle displacement, respectively. It has become.
That is, since the attitude angle change amount θ with respect to the reference vehicle state is equal to the geomagnetic change amount, it can be obtained from the output signal of the geomagnetic sensor 20, and the moving speed V of the vehicle 200 is detected by the wheel speed sensor 19. It can be determined by the product of the rotational speed and circumference of the front wheel Wf. For this reason, the X-axis component and the y-axis component of the vehicle displacement can be obtained by the following equations.

  The path defining means 32 is a means for defining a movement path (reference movement path) between the reference position and the target position, and is defined as, for example, a straight line connecting the reference position and the target position.

  The posture angle change amount limiting means 33 sets the posture angle change amount per movement distance of the vehicle 200 to a certain value or less, thereby limiting the rapid posture change of the vehicle 200 and making the vehicle 200 clear due to some error. Prevent going in different directions.

  The control means 34 is configured so that the target vehicle state (geomagnetic change amount and relative position change amount) set by the target vehicle state setting means 30 is obtained while the vehicle 200 actually moves from the reference position to the target position. The electric motor 4 is controlled by feeding back the amount of change in geomagnetism and the amount of change in relative position of the vehicle 200 (output signals of the geomagnetic sensor 20 and the relative position detection means 31). The control means 34 of this embodiment further receives signals from the path defining means 32 and the posture angle change amount limiting means 33, and the vehicle 200 moving from the reference position to the target position is along the reference movement path, and The electric motor 4 is controlled so as not to exceed a predetermined posture angle change amount.

  Next, the operation of this steering control device will be described with reference to the left rear side parallel parking shown in FIGS.

  First, the vehicle 200 is stopped at the parking reference position (1) by the driver's own steering, and the left rear parallel parking mode is selected from the mode selection switches 15a to 15d on the operation panel 11 (see FIG. 7). Then, automatic steering is started by pressing the start switch 16.

  When the automatic steering is thus started, data corresponding to the left rear parallel parking is read in the controller 206, and the geomagnetic change amount and the relative position change amount indicating the target vehicle state are set by the target vehicle state setting means 30. The The geomagnetic change amount and the relative position change amount set at this time are θ1, (−x1, + y1) for forward movement and θ2, (+ x1, −2y) for backward movement. At the same time, the attitude angle of the geomagnetic reference vehicle 200 at the parking reference position (1) is detected by the geomagnetic sensor 20, the value is stored, and the moving distance of the vehicle 200 from the parking reference position (1) is stored. Is detected (calculation based on the equations (10) and (11)). When the target vehicle state is set by the target vehicle state setting means 30, the reference movement route of the vehicle 200 is then defined by the route defining means 32. In this case, the reference movement route is, for example, a straight line connecting the parking reference position (1) and the first target position (2).

  When the depression of the brake pedal is released from this state and the accelerator operation is performed as necessary, the electric motor 4 is controlled by the control means 24 with the parking reference position (1) as the reference position and the first target position as the target position. While being done, the vehicle 200 moves forward. At this time, the controller 206 receives the output signals from the geomagnetic sensor 20 and the relative position detecting means 31, the vehicle 200 is along the standard movement path, and finally the geomagnetic change amount and the relative position change amount are θ1, ( The control means 34 controls the electric motor 4 so that −x1, + y1). At this time, since the control by the control unit 34 is restricted by the posture angle change by the posture angle change amount limiting unit 33, at the beginning of the forward movement, as shown in FIGS. Change the posture angle. Thus, when the vehicle 200 moves forward to some extent and rides on the standard movement path before the first target position (2), the geomagnetic change amount is maintained as θ1 (the attitude angle based on the geomagnetic reference is α + θ1). The vehicle 200 moves forward. Then, when the controller 200 determines that the vehicle 200 travels on the standard movement route as it is and the relative position change amount has reached (−x1, + y1), the display on the monitor 10 and the instruction from the voice teaching speaker 9 are performed. Thus, the driver is informed that the vehicle 200 should be stopped, and the vehicle 200 stops at the turn-back position (2 ′) when the driver depresses the brake pedal.

  Thereafter, when the driver switches the shift range to R according to the instruction of the voice teaching speaker 9 and gradually releases the depression of the brake pedal and performs an accelerator operation as necessary, the vehicle 200 changes the posture angle (geomagnetic change amount). Retreating is started while maintaining θ1. When the vehicle 200 moves backward, the reference position is set to the first target position (2), the target position is set to the second target position (3), and the control by the control means 34 is performed while the vehicle 200 remains at a constant posture angle. It starts when it returns to the target position (2). At the time of returning to the first target position (2), the geomagnetic reference vehicle 200's attitude angle at that time is detected by the geomagnetic sensor 20, the value is stored, and the first target position is also stored. Detection of the travel distance of the vehicle 200 from (2) (calculation by the above-described equations (10) and (11)) is started. At this time, the reference movement path of the vehicle 200 is a straight line connecting the first target position (2) and the second target position (3).

  Thus, when the vehicle 200 starts moving backward from the first target position (2), the controller 206 causes the vehicle 200 to follow the new reference movement path, and finally the geomagnetic change amount and the relative position change amount are θ2 respectively. The control means 34 controls the electric motor 4 so as to be −θ1, (+ x1, −2y1). As a result, at the beginning of the backward movement from the first target position (2), the posture angle is changed to the right by a certain amount of change as shown in FIGS. When the vehicle 200 is on the reference movement path before the target position (3) of 2, the vehicle 200 moves backward while maintaining the geomagnetic change amount at θ2−θ1 (the posture angle based on the geomagnetic reference is α + θ2). When the controller 206 determines that the vehicle 200 travels on the standard movement route as it is and the relative position change amount has reached (+ x1, -2y1), the driver is instructed to brake by the monitor display and voice teaching. The When the driver depresses the brake pedal at this time, the vehicle 200 stops at the final parking position (3 ′) that has passed the second target position (3).

  As described above, the steering control device can perform reliable automatic steering so that the vehicle 200 fits in the parking frame 21 in a predetermined posture. However, the reference posture angle data corresponding to the amount of movement of the vehicle 200 is one by one. Unlike the conventional one that has been stored, it is only necessary to store the vehicle state at the target position as the geomagnetic change amount and the relative position change amount, so that the memory capacity required for storage can be greatly reduced. Further, in this apparatus, since the attitude angle of the vehicle is directly detected by the geomagnetic sensor, the steering angle of the steering wheel, the turning angle of the wheel, etc. are detected, and the attitude angle of the vehicle is estimated from these. Unlike conventional types, it is not affected by errors in the steering mechanism, spoke angle, camber, caster, etc., or changes in external factors such as the number of passengers, loading weight, tire slip, and road surface conditions. Therefore, from this, accurate steering control can always be realized.

  In the steering control device of this embodiment, the route defining means 32 defines a standard movement route of the vehicle 200 that connects the reference position and the target position, along the movement route, and finally the target geomagnetic change amount. Since the electric motor 4 is controlled so as to be in the relative movement position, the motor control is easy, and automatic steering is performed without any trouble even when the traveling direction of the vehicle 200 is temporarily out of order for some reason. You can continue.

  Although not described above, the control means 34 of the controller 206 controls the electric motor 4 so as to avoid the object when the obstacle detection means 13 detects the obstacle. Also good. When the control means 34 performs such control, it is possible to automatically avoid an object that becomes an obstacle during automatic steering as shown in FIG. 3, and after the avoidance, the vehicle follows the reference movement path, and Since the control is continued so as to finally reach the target geomagnetic change amount and the relative movement position, in most cases, it is not necessary to interrupt the automatic steering control.

In addition, this invention is not limited to the said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, in the above description, the embodiment adopting the electric power swirling in which the steering shaft and the steering mechanism are mechanically connected has been described. It is also possible to do. In the above, two vehicle state setting points (first target position (2) and second target position (3)) are used to guide the vehicle at the parking reference position (1) into the parking frame. However, the number of these setting points is not limited to two and may be arbitrary.
Furthermore, the position and number of vehicle state setting points may be arbitrarily set and adjusted by the driver. In this case, for example, even when the parking frame is provided obliquely with respect to the road, the vehicle can be guided into the parking frame with an appropriate entry angle.

The functional block diagram which shows schematic structure of one Embodiment of this invention. The schematic diagram explaining the action | operation of the embodiment. The schematic diagram explaining the action | operation at the time of vehicle advance of the embodiment. The schematic diagram explaining the action | operation at the time of vehicle reverse of the embodiment. The characteristic view which shows the relationship between the movement distance of the vehicle of the same embodiment, a posture angle, and a position coordinate. The schematic block diagram of the vehicle in the embodiment and a reference example. The top view of the garage operation panel in the said embodiment and a reference example. The schematic diagram which shows the example of installation of the magnetic sensor in the said embodiment and a reference example. The schematic diagram which shows the other installation example of the magnetic sensor in the said embodiment and a reference example. The schematic diagram explaining the condition where the vehicle of a reference example advances at the time of parallel parking. The schematic diagram explaining the condition where the vehicle of the reference example moves backward during parallel parking. The characteristic view which shows the relationship between the movement distance at the time of the parallel parking of the vehicle of the reference example, and a posture angle. The schematic diagram explaining the condition where the vehicle of the reference example moves forward during parallel parking. The schematic diagram explaining the condition where the vehicle of the reference example moves backward during parallel parking. The characteristic view which shows the relationship between the movement distance at the time of parallel parking of the vehicle of the reference example, and a posture angle.

Explanation of symbols

3 Steering mechanism 4 Electric motor (actuator)
DESCRIPTION OF SYMBOLS 13 Obstacle detection means 20 Geomagnetic sensor 30 Target vehicle state setting means 31 Relative position detection means 32 Path | route definition means 33 Posture angle change amount restriction means 34 Control means

Claims (3)

A steering mechanism that steers the wheels;
An actuator for driving the steering mechanism;
A vehicle steering control apparatus comprising: a control unit that controls the actuator when the vehicle moves from a reference position to a target position;
A geomagnetic sensor for detecting a change in geomagnetism according to the attitude angle of the vehicle;
A wheel speed sensor for detecting the wheel speed of the vehicle ;
Relative position detection means for detecting a relative position from a reference position of the vehicle by receiving output signals from the geomagnetic sensor and the wheel speed sensor, and accumulating and adding components in two axial directions orthogonal to the displacement of the vehicle.
A target vehicle state setting means for setting the states of the vehicle at the target position, as geomagnetic variation and the relative position change amount from the reference position,
Providing route defining means for defining a moving route of the vehicle connecting the reference position and the target position ;
The control means is set by the target vehicle state setting means when the vehicle actually moves from the reference position to the target position along the movement route specified by the route specifying means and at the target position. The steering actuator is controlled so that the amount of change in geomagnetism and the amount of change in relative position are the same, and the geomagnetic change set by the target vehicle state setting means when the vehicle rides on the moving path before the target position. A steering control device for a vehicle , wherein the steering actuator is controlled so as to maintain the amount . Provided is a failure detection means for detecting an object that becomes an obstacle when the vehicle moves from the reference position to the target position, and when the obstacle detection means detects an obstacle, the control means avoids the object. The vehicle steering control device according to claim 1 , wherein the actuator is controlled. 3. The vehicle steering control device according to claim 1, further comprising posture angle change amount limiting means for limiting the amount of change in the posture angle of the vehicle during control.

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