JP5594468B2 - Parking assistance system - Google Patents

Description

  The present invention relates to a parking assistance system, and more particularly to a driving assistance system that controls rotation of a steering wheel during parking assistance (automatic parking) of a vehicle equipped with a steer-by-wire system.

  The vehicle is equipped with a steer-by-wire system equipped with a steering motor that steers the steering wheel according to the rotation of the steering wheel, and the driver steers the steering wheel. There is a vehicle equipped with a parking support system that includes automatic parking means for automatically parking a vehicle at a target parking position.

JP 2004-203315 A

  In the parking assistance device according to Patent Document 1, when a parking assistance (automatic parking) system is used, when the steering wheel of the vehicle is in a rotation mode, the actuator automatically controls the rotation of the steering wheel.

Conventionally, in automatic parking using power steering, the parking operation is performed by rotating the steering wheel and steering the steered wheels so that the vehicle moves along the calculated route.
For this reason, during parking assistance, it is not possible to choose not to rotate the steering wheel at the driver's will, and the steering wheel automatically rotates, so the driver's clothing may wrap around the steering wheel or the steering wheel There was a risk of unexpected situations such as bumping into the driver's hand.
In automatic parking using power steering, automatic parking is stopped when the rotating steering wheel is stopped during automatic parking.
However, if the steering wheel is always kept at the neutral position, the conventional method has a disadvantage that automatic parking cannot be stopped.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to eliminate the possibility of an unexpected situation such as a driver's clothing wrapping around a steering wheel or a steering wheel hitting a driver's hand during parking assistance. It is to provide a parking assistance system.

The present invention provides a parking assist system comprising: an automatic parking unit that automatically parks a vehicle at a target parking position; and a steer-by-wire system that includes a steering motor that steers the steered wheels according to rotation of a steering wheel. position of said steering wheel also steered wheel is steered by the steering motor during the automatic parking means comprises a mode that is held, during execution of the automatic parking unit on the steering angle of the steering wheel A mode for rotating the steering wheel by the steering motor, and mode switching means for switching between the two modes .

  The parking assist system according to the present invention eliminates the possibility of an unexpected situation such as a driver's clothing wrapping around the steering wheel or a steering wheel hitting the driver's hand during parking assist. be able to.

FIG. 1 is a flowchart of parking assistance. (Example) FIG. 2 is a configuration diagram of the parking assistance system. (Example)

  The present invention aims at eliminating the possibility of an unexpected situation such as a driver's clothing wrapping around a steering wheel or a steering wheel hitting a driver's hand when steering assisting. This is achieved with the wheel in the neutral position.

1 and 2 show an embodiment of the present invention.
In FIG. 2, 1 is a vehicle, and 2 is a steer-by-wire system mounted on the vehicle 1. The steer-by-wire system 2 includes an operation mechanism 3 and a steering mechanism 4 that are not mechanically connected, and electrically drives the steering mechanism 4 so that the gear ratio can be freely changed.

As shown in FIG. 2, the operation mechanism 3 is provided with a steering shaft 6 that is pivotally supported with respect to a steering column 5 that is a vehicle body structure portion, and is integrally provided at an upper end portion of the steering shaft 6 and can be manually operated. A steering wheel 7, a reaction force generating means 8 and a vibration generating mechanism 9 attached to the lower end portion of the steering shaft 6 are provided. The reaction force generating means 8 gives a reaction force to the steering wheel 7. The vibration generating mechanism 9 transmits fine vibrations to the steering wheel 7 via the steering shaft 6.
Further, between the first steering wheel rotation angle detection means 10 that detects the rotation angle of the steering wheel 7 at the upper end of the steering column 5, and between the lower end of the steering column 5 and the reaction force generation means 8, A torque sensor 11 for detecting the rotational torque of the steering wheel 7, a second steering wheel rotational angle detecting means 12 for detecting the rotational angle of the steering wheel 7, and a clutch 13 are attached. The clutch 13 connects or releases the steering wheel 7 to the reaction force generating means 8 and the vibration generating mechanism 9.
A steering motor 14, which is an electric motor connected to a built-in gear, is attached to the steering column 5. The steering motor 14 is attached to the steering shaft 6 and generates a reaction force corresponding to a road surface reaction force or an assist force (power steering force) for assisting rotation in the steering wheel 7.

The steering mechanism 4 is connected to the left front wheel 15L and the right front wheel 15R as steering wheels, the left tie rod 16L and the right tie rod 16R for driving the left front wheel 15L and the right front wheel 15R, and the left tie rod 16L and the right tie rod 16R. A steering box 17 incorporating a rack shaft, a pinion shaft 18 connected to the rack shaft of the steering box 17, and a steering motor gear box 19 attached to the pinion shaft 18 and incorporating a gear are provided. The pinion shaft 18 functions as a steered shaft connected to the left front wheel 15L and the right front wheel 15R as steering wheels via the left tie rod 16L and the right tie rod 16R.
The pinion shaft 18 is provided with first turning angle detection means 20 and second turning angle detection means 21 for detecting the rotation angle of the pinion shaft 18 on the upper side of the steering motor gear box 19.
Two first steering motors 22 and 23 are attached to the steering motor gear box 19 as actuators so as to be connected to the built-in gear. The first steering motor 22 and the second steering motor 23 perform steering control of the left front wheel 15L and the right front wheel 15R, which are the steering wheels, according to the rotation of the steering wheel 7.

The steer-by-wire system 2 is driven by a steering control device 24 as a control device. The steering control device 24 includes an operation control device 25, a first steering control device 26, and a second steering control device 27, and further includes a reaction force generation mechanism 8, a vibration generation mechanism 9, and a first steering. Wheel rotation angle detection means 10, torque sensor 11, second steering wheel rotation angle detection means 12, steering motor 14, first turning angle detection means 20, second turning angle detection means 21, first steering motor 22, and first 2 The steering motor 23 is in communication.
The operation control device 25 directly communicates with the steering motor 14, the vehicle information detection means 28, and the display alarm device 29, and commands the reaction force and assist force of the steering motor 14.
The first steering control device 26 directly communicates with the first steering motor 22 and controls driving of the first steering motor 22.
The second steering control device 27 directly communicates with the second steering motor 23 and controls the driving of the second steering motor 23.
The vehicle information detection means 28 detects various vehicle information such as the vehicle speed, the engine speed, the ignition switch state, the shift position, etc., and outputs it to the operation control device 25.
The display alarm device 29 warns the display of a warning light or a buzzer.
In this steer-by-wire system 2, the steering wheel 7 and the left front wheel 15 </ b> L and the right front wheel 15 </ b> R as the steering wheels are mechanically separated, and the first steering motor 22 and the second steering motor 23 according to the rotation of the steering wheel 7. To steer the left front wheel 15L and the right front wheel 15R.

In addition, the vehicle 1 is equipped with a parking assistance system 30 that is integrated into the steer-by-wire system 2. The parking assist system 30 includes automatic parking means 31 that automatically parks the vehicle 1 at a target parking position (automatic parking) without the driver steering the steering wheel 7. The automatic parking means 31 communicates with the steering control device 24 and outputs a steering instruction or mode instruction signal for the left front wheel 15L and the right front wheel 15R, while receiving an automatic parking stop instruction signal from the steering control device 24. .
The steering control device 24 maintains the position of the steering wheel 7 even when the left front wheel 15L and the right front wheel 15R are steered by the first steering motor 22 and the second steering motor 23 during execution of the automatic parking means 31.
In this way, at the time of the parking assist, the holding position of the steering wheel 7 is because, or wrapped around the clothes steering wheel 7 of the driver, unexpectedly such as a steering wheel 7 is bumping into the hands of the driver There is no risk of accidents occurring.

Further, when the rotation of the steering wheel 7 is detected during automatic parking by the first steering wheel rotation angle detection means 10 and the second steering wheel rotation angle detection means 12, the steering control device 24 outputs an automatic parking stop command signal. Output. On the other hand, the automatic parking means 31 stops automatic parking when an automatic parking stop command signal is input.
Thus, during automatic parking, the driver can stop automatic parking even if the steering wheel 7 is kept in the neutral position.

Further, the steering control device 24 rotates the steering wheel 7 according to the steering angle of the left front wheel 15L and the right front wheel 15R by the first steering motor 22 and the second steering motor 23 during the execution of the automatic parking means 31. Mode (mode 1) and the second mode (mode 2) in which the position of the steering wheel 7 is held by the steering motor 14 even when the left front wheel 15L and the right front wheel 15R are steered during execution of the automatic parking means 31. And have.
The automatic parking means 31 communicates with a mode switching means (switch) 32 for switching between the first mode (mode 1) and the second mode (mode 2) in the steering control device 24. The automatic parking means 31 outputs a mode instruction signal to the steering control device 24 according to the state of the mode switching means (switch) 32. On the other hand, the steering control device 24 switches between the first mode (mode 1) and the second mode (mode 2) in accordance with the input mode instruction signal.
Thereby, the driver | operator can select the behavior of the steering wheel 7 in automatic parking.

Next, parking assistance control according to this embodiment will be described along the flowchart of FIG.
As shown in FIG. 1, when the program of the steering control device 24 is started (step A01), the parking assist system 30 is operated (step A02), and the mode switching means 32 is switched between the first mode (mode 1) and the second mode. It is determined which mode (mode 2) is selected (step A03).
If the first mode (mode 1) is selected in step A03, the steering wheel 7 is rotated (step A04), and it is determined whether or not the steering wheel 7 is not operated (step S04). A05).
If this step A05 is YES, it is determined whether or not the vehicle has reached the target parking position (step A06). If this step A06 is NO, the process returns to step A05.
If this step A06 is YES, or if the step A05 is NO, the parking support system 30 is stopped (step A07), and the program is ended (step A08).
On the other hand, when the second mode (mode 2) is selected in the step A03, the steering wheel 7 is not rotated (step A09), and the steering wheel 7 is preset to the right or left. It is determined whether or not a certain angle (for example, 30 deg) has not been cut (step A10).
If this step A10 is YES, it is determined whether or not the vehicle has reached the target parking position (step A11). If this step A11 is NO, the process returns to step A10.
When this step A11 is YES, or when the said step A10 is NO, it transfers to the said step A07 and stops the parking assistance system 30.

  The parking assistance system of the present invention can be applied to various vehicles.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Steer-by-wire system 3 Operation mechanism 4 Steering mechanism 7 Steering wheel 10 First steering wheel rotation angle detection means 12 Second steering wheel rotation angle detection means 14 Steering motor 15L Left front wheel (steering wheel)
15R Front right wheel (steering wheel)
18 Pinion shaft (steering shaft)
DESCRIPTION OF SYMBOLS 20 1st turning angle detection means 21 2nd turning angle detection means 22 1st steering motor 23 2nd steering motor 24 Steering control apparatus 30 Parking assistance system 31 Automatic parking means 32 Mode switching means

Claims (2)

Automatic parking means for automatically parking the vehicle at the target parking position;
In a parking assistance system comprising a steer-by-wire system comprising a steering motor that steers the steered wheel according to the rotation of the steering wheel,
During the execution of the automatic parking means, even if the steering wheel is steered by the steering motor , the position of the steering wheel is maintained , and
A mode in which the steering wheel is rotated by the steering motor in accordance with a steering angle of the steering wheel during execution of the automatic parking means;
A parking support system comprising mode switching means for switching between the two modes. A steering wheel rotation angle detection means for detecting the rotation angle of the steering wheel;
When the steering wheel is steered by the steering motor during execution of the automatic parking means, the position of the steering wheel is in the held mode.
The automatic parking is stopped when the steering wheel is turned off so that the rotation angle of the steering wheel detected by the steering wheel rotation angle detection means becomes a predetermined value or more. The described parking assistance system.

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