JP2005084988A - Traveling lane deviation preventing device for vehicle, traveling lane deviation detecting device and facility for detecting traveling lane deviation of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the deviation from a traveling lane of a vehicle by using the transmitting/receiving function of a tire air pressure sensor mounted on the tire or wheel of a vehicle. <P>SOLUTION: A tire air pressure sensor mounted on the tire or wheel of a vehicle is provided with a communicating means which performs radio communication with a traveling lane guide unit arranged on a road surface along a traveling line. This traveling lane deviation detecting device of the vehicle is characterized by providing a deciding means which decides the traveling position of right and left directions of the vehicle in the traveling lane based on the result of the radio communication. Also, a facility for detecting the traveling lane of the vehicle is provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle lane departure detection facility, a vehicle lane departure detection device, and a vehicle travel lane departure prevention device.

  In recent years, vehicles equipped with a so-called lane keeping system that assists the driver in order to keep the traveling direction of the vehicle within the traveling lane are known. This lane keeping system detects a white line indicating a traveling lane on the road surface and assists the driver in following the lane. As this lane keeping system, for example, an image of a white line is captured by a CCD camera provided at the upper part of the windshield (in the room) or the lower part of the left and right door mirrors, and the captured image is subjected to image processing and image recognition by the in-vehicle ECU. There are systems that issue a warning to the driver or add a steering torque to assist the driver in following the lane according to the amount of lateral displacement in the lane (see Patent Document 1, Patent Document 2, etc.).

  However, in the lane keeping system using the in-vehicle camera, the camera body to be used is expensive and expensive, and also causes an increase in the weight of the vehicle. Also, when the white line itself is not visible due to obstacles, rain, snow, fog, gas, oil, etc., when the white line is lost due to wear, etc., when a vehicle or a large vehicle is traveling ahead, etc. However, since the white line image cannot be captured by the camera, the lane keeping system does not operate due to the inability to recognize the lane.

Further, in a lane keeping system using an in-vehicle camera, if the camera malfunctions, the system itself may malfunction, and there is a problem that it takes time to process white line image data. In addition, when using a stereo camera as an in-vehicle camera, the accuracy of white line image capture depends on the accuracy of the camera mounting angle, and support strength (durability, vibration) is a problem when the camera is mounted on a door mirror. It becomes. Furthermore, in a camera in which the photographing lens is exposed to the outside, there is a problem that white line detection accuracy is greatly affected by dirt, scratches, damage, and the like of the lens.
Japanese Patent Laid-Open No. 07-104850 (Claim 8 etc.) JP-A-11-321690 (Claim 5 etc.)

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a device for detecting a deviation from a traveling lane of a vehicle by using a transmission / reception function of a tire pressure sensor mounted on a tire or a wheel of the vehicle. It is an object of the present invention to provide an apparatus for preventing a vehicle and equipment provided on a road surface to detect a deviation of a vehicle.

  In order to solve the above-mentioned problem, the invention according to claim 1 is an apparatus for detecting a deviation of a vehicle from a traveling lane provided on a road surface, the traveling lane being arranged on the road surface along the traveling lane. A tire pressure sensor mounted on a tire or a wheel of the vehicle includes a communication unit that wirelessly communicates with the guide, and includes a determination unit that determines a lateral travel position of the vehicle in the travel lane based on a result of the wireless communication. A vehicle lane departure detection apparatus characterized by the above.

  In this vehicle lane departure detecting device, a lane guide installed on the road surface and a tire pressure sensor mounted on the vehicle communicate wirelessly via communication means provided in the tire pressure sensor, and the wireless communication Based on the result, the determination means determines the travel position of the vehicle in the left-right direction within the travel lane, so that the deviation of the vehicle from the travel lane can be detected.

  The invention according to claim 2 is an apparatus for preventing a vehicle from departing from a traveling lane provided on a road surface, and is provided in a tire pressure sensor mounted on a tire or a wheel of the vehicle. A communication unit that wirelessly communicates with a travel lane guide disposed on the road surface along the travel lane, a determination unit that determines a lateral travel position of the vehicle in the travel lane based on a result of the wireless communication, and the determination A vehicle travel lane departure prevention apparatus comprising: a travel prevention means for notifying a driver of a departure state from a travel lane of a vehicle based on a determination result by the means or assisting steering of the vehicle. And

  In this vehicle travel lane departure prevention device, a travel lane guide disposed on the road surface and a tire air pressure sensor mounted on the vehicle communicate wirelessly via communication means, and determination is made based on the result of the wireless communication. A means determines a travel position in the left-right direction of the vehicle in the travel lane. Then, based on the determination result, the departure prevention means notifies the driver of the departure state from the traveling lane of the vehicle, or prevents the departure from the traveling lane of the vehicle by assisting the steering of the vehicle. Can do.

  Furthermore, the invention described in claim 3 is a vehicle lane departure detection facility for detecting a vehicle departure from a vehicle lane provided on a road surface, the antenna for transmitting and receiving radio waves, and the antenna Vehicle lane guides provided with vehicle tires or tire pressure sensors mounted on wheels and transmission / reception means for wireless communication are arranged at predetermined intervals along the road lane on the road surface. The feature of the vehicle lane departure detection facility is a feature of the invention.

  In this vehicle lane departure detection facility, a travel lane guide arranged at predetermined intervals along the travel lane on the road surface communicates wirelessly with a tire pressure sensor mounted on a vehicle tire or a wheel. As a result, information for detecting a deviation from the traveling lane of the vehicle can be provided to a deviation detecting device provided on the vehicle side.

  According to the first aspect of the present invention, there is no need for equipment that causes the cost of a camera or the like and causes an increase in vehicle weight. Deviation from the driving lane can be detected while accurately grasping the left and right vehicle body widths by a tire pressure sensor mounted on a tire or a wheel located on the side of the vehicle. Further, if wireless communication between the tire pressure sensor and the travel lane guide is possible, the deviation can be detected while maintaining high reliability if at least one tire pressure sensor is operating. Furthermore, since the air pressure sensor is not exposed to the outside, the detection accuracy of the deviation of the traveling lane is not greatly affected by dirt, scratches, damage, or the like. Furthermore, since the deviation from the traveling lane can be detected by wireless communication with the traveling lane guide, the deviation from the traveling lane can be detected at high speed without requiring image processing time. In particular, it is possible to construct a lane keeping system with almost no increase in cost by effectively utilizing the transmission / reception function of a pneumatic pressure sensor (TPMS), which is expected to be installed in many mass-produced vehicles in the future.

  According to the second aspect of the present invention, the traveling lane guide disposed on the road surface and the tire pressure sensor mounted on the vehicle wirelessly communicate via the communication means included in the tire pressure sensor, and the wireless communication. Based on the result, the determination means determines the traveling position of the vehicle in the lateral direction in the traveling lane. Then, based on the determination result, the departure prevention means notifies the driver of the departure state from the traveling lane of the vehicle, or prevents the departure from the traveling lane of the vehicle by assisting the steering of the vehicle. Can do. Thus, it is possible to assist the driver who steers the vehicle by preventing deviation from the traveling lane.

  According to the third aspect of the present invention, the vehicle is determined by the information provided to the deviation detecting device provided on the vehicle side by the traveling lane guides arranged at predetermined intervals along the traveling lane on the road surface. Deviations from the driving lane can be detected. Therefore, if this lane departure detection facility is installed on an expressway or the like, it is useful for preventing the vehicle from departing from the lane.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a vehicle lane departure detection device and a vehicle lane departure detection facility according to an embodiment of the present invention.
In FIG. 1, in the direction of arrow V (traveling) in a travel lane L delimited by two white lines WL1 and WL2 arranged on the road surface R at a predetermined interval (for example, an interval of 20 m) in the travel direction of the road surface. The vehicle C traveling in the direction) includes tire pressure sensors 18 (see FIG. 2) on the four wheels 11, 12, 13, and 14.
On the other hand, the left and right white lines WL1, WL2 arranged on the road surface R are provided with travel lane guides 2LF, 2LE, 2RF, 2RE at both ends in the longitudinal direction.

  The tire pressure sensor 18 is connected to an air injection valve 16 provided on the wheel 15 of the wheel 11 and provided inside the tire 17 as shown in an enlarged view of the wheel 11 in FIG. The tire pressure sensor 18 is connected to an air injection valve 16 provided on the rim 19 of the wheel 15 as shown in FIGS. 3 and 4, and a pressure sensor 20 for measuring tire pressure, as shown in FIG. In addition, an information signal related to the detected tire pressure is transmitted to an in-vehicle control unit ECU provided on the vehicle body side, and a transmitter / receiver 21 that receives a command signal from the in-vehicle control unit ECU, a pressure sensor 20 and a transmission / reception unit The electronic circuit part 22 which controls the instrument 21 and the battery 23 which supplies electric power to each part of these pressure sensors 20, the transmitter / receiver 21, and the electronic circuit part 22 are provided. As the pressure sensor 20, a sensor using a pressure sensitive element such as a diaphragm or a piezoelectric element is used. The transceiver 21 communicates with the in-vehicle ECU by, for example, an analog method using FM modulation or a digital method using PCM modulation.

  Further, the traveling lane guides 2LF, 2LE, 2RF, 2RE include an antenna 24 and a transmitter / receiver 25 connected to the antenna 24, as shown in the traveling lane guide 2LE in FIG. The antenna 24 and the transmitter / receiver 25 are embedded in the road surfaces at both ends in the longitudinal direction of white lines WL1 and WL2 provided in a chain line shape at predetermined intervals on both the left and right sides of the traveling lane L. The transmitter / receiver 25 is supplied with power by a power supply unit (not shown). The power supply means may be of any form as long as it can supply power to the transceiver 25 and is not particularly limited. For example, the power supply means may be a power line embedded in the ground on the road surface, or a solar power generator disposed in the vicinity of the transmitter / receiver 25 or on the road side.

  In the travel lane guides 2LF, 2LE, 2RF, 2RE, as shown in FIGS. 1 and 2, a radio wave EW having a predetermined frequency is transmitted. On the other hand, the tire pressure sensors 18 mounted on the four wheels mounted on the front, rear, left and right sides of the vehicle receive the radio waves EW transmitted from the travel lane guides 2LF, 2LE, 2RF, 2RE, and receive the received radio waves EW. The receiving sensitivity (power, voltage, electric field strength) and the like are detected. Information on radio wave reception sensitivity detected by each tire pressure sensor 18 is transmitted to an in-vehicle ECU (discriminating means) as shown in FIG. Then, the in-vehicle ECU determines a traveling position in the left-right direction of the vehicle in the traveling lane based on the reception sensitivity of the radio wave received by each tire pressure sensor 18, and based on the determination result by the determination unit. A departure prevention means for notifying the driver of a departure state from the traveling lane of the vehicle or assisting the steering of the vehicle is provided. Then, the in-vehicle ECU determines the lateral travel position of the vehicle in the travel lane by the determination means, and notifies the driver of the deviation from the travel lane of the vehicle based on the determination result, or steers the vehicle. To assist.

  The determination by the determination means of the in-vehicle ECU is, for example, when the deviation from the traveling lane is detected in an analog manner by radio waves transmitted from the transceivers 25 of the traveling lane guides 2LF, 2LE, 2RF, 2RE. Depending on the deviation to the left or right in the travel lane L, the reception intensity of the radio waves received by the air pressure sensors 18 mounted on the left and right wheels of the vehicle body will be different. For example, the reception intensity of radio waves (for example, 70 MHz, 0.1 mW FM waves) received from the left and right traveling lane guides 2LF and 2RF by the respective air pressure sensors 18 mounted on the left and right front wheels of the vehicle C will be described. As shown in FIGS. 6 (a) to 6 (c), the left and right air pressure sensors 18 have different or the same radio wave reception intensity due to the deviation in the traveling lane of the vehicle. That is, when the vehicle is deviated to the left side of the traveling lane, as shown in FIG. 6A, the intensity of the radio wave received by the left tire pressure sensor 18 is greater than the radio wave received by the right tire pressure sensor 18. Since it indicates that the received signal intensity is too high, it is detected that the vehicle may deviate to the left side of the traveling lane and the vehicle may deviate in the left direction. On the other hand, when the vehicle is deviated to the right side of the travel lane, as shown in FIG. 6B, the difference in reception intensity is opposite to that of FIG. 6A, and the vehicle is deviated to the right side of the travel lane. Thus, it is detected that the vehicle may deviate in the right direction. When the vehicle is traveling in the center of the traveling lane, as shown in FIG. 6C, the reception intensity of the radio waves received by the left and right tire pressure sensors 18 shows the same intensity. It is determined that the vehicle travels in the center without deviating in the travel lane and is not in a deviating state. At this time, if a certain threshold value is set for the reception intensity, it is effective to cancel the deviation of the vehicle in a predetermined range and accurately detect the deviation of the vehicle.

  Further, when a deviation from the driving lane is detected digitally by radio waves transmitted from the transmitter / receiver 25 of the driving lane guides 2LF, 2LE, 2RF, 2RE, for example, it is transmitted from the left and right tire pressure sensors 18. As shown in FIGS. 7 (a) and 7 (b), when the radio wave indicates a phase difference, the deviation of the vehicle from the travel lane can be detected. For example, with respect to the radio wave EW received by the right tire pressure sensor 18 (FIG. 7A), the radio wave EW received by the left tire pressure sensor 18 (FIG. 7B) has a phase as shown in FIG. Is delayed, it is determined that the vehicle tends to deviate from the center of the lane to the left and deviate in the direction. At this time, information may be transferred by transmitting radio waves from the tire pressure sensor 18 to the travel lane guides 2LF, 2LE, 2RF, 2RE. For example, as shown in FIG. 8, the radio pressure transmitted by the tire pressure sensor 18 may be transmitted with identification information for identifying tire pressure measurement data and data for detecting lane departure detection. Good. As a result, the tire pressure sensor 18 does not transmit the tire pressure measurement data to be transmitted to the vehicle-mounted ECU and the data for detecting the lane departure from the separate radio waves. There is an advantage that can be sent to. For example, as shown in FIG. 8, together with an ID for identifying a tire or a wheel on which the tire pressure sensor 18 is mounted, data 1 relating to a measured value of the tire pressure, and data 2 for detecting a lane departure, It can be transmitted with the same radio wave.

  In the above embodiment, the travel lane guides 2LF, 2LE, 2RF, 2RE are shown as examples provided on the white lines on both sides of the travel lane, but the present invention is not limited to this embodiment. For example, it may be installed at a predetermined interval in the center of the travel lane, or may be installed at a predetermined interval in both the white line and the center of the travel lane in order to further improve detection accuracy. In addition, the tire pressure sensor need not be mounted on all four wheels of the vehicle, and may be mounted on one of the four wheels. Further, the travel lane guides 2LF, 2LE, 2RF, 2RE and the tire air pressure sensor 18 are deviated from the travel lane of the vehicle from the phase difference of the received radio waves at the tire air pressure sensor 18 using PCM radio waves in the vicinity of the far infrared ray. May be requested.

  As described above, when a vehicle deviation from the traveling lane is detected by the discriminating means of the in-vehicle ECU, the in-vehicle ECU blinks an alarm sound or a warning light, or the front part of the driver's seat as shown in FIG. The driver is notified by, for example, displaying an image indicating deviation from the traveling lane on the display device installed in the vehicle. Also, control information is transmitted from the in-vehicle ECU to the steering control mechanism mounted on the vehicle, and control such as increasing the steering torque in the direction of deviation of the vehicle is performed in order to prevent the vehicle from deviating from the travel lane. You may do it.

It is a conceptual diagram which shows the driving | running | working lane deviation detection apparatus and deviation detection installation in the embodiment of this invention. It is a figure which expands and shows a part of FIG. It is a schematic cross section which expands and shows a part of wheel. It is a schematic cross section which shows the structural example of a tire pressure sensor. It is a mimetic diagram explaining transmission of information from a tire pressure sensor to in-vehicle ECU. (A)-(c) is a conceptual diagram explaining discrimination | determination of the deviation from the driving | running lane of a vehicle by the received intensity which a tire pressure sensor receives from a driving lane guide, respectively. (A) And (b) is a conceptual diagram explaining discrimination | determination of the deviation from a driving lane by a digital system. It is a schematic diagram explaining an example of the information signal from a tire pressure sensor. It is a schematic diagram which shows the example of a display which notifies a driver | operator the deviation of the vehicle from a driving | running lane.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Road surface WL1, WL2 White line L Travel lane 11, 12, 13, 14 Wheel 18 Tire pressure sensor C Vehicle 2LF, 2LE, 2RF, 2RE Travel lane guide 24 Antenna 25 Transmitter / receiver

Claims (3)

An apparatus for detecting a deviation of a vehicle from a traveling lane provided on a road surface,
An air pressure sensor mounted on a tire or a wheel of the vehicle includes a communication means for wirelessly communicating with a traveling lane guide disposed on the road surface along the traveling lane, and the vehicle in the traveling lane is based on the result of the wireless communication. A vehicle lane departure detection apparatus comprising: a determination unit that determines a left and right traveling position of the vehicle. An apparatus for preventing a vehicle from departing from a traveling lane provided on a road surface,
Communication means provided on an air pressure sensor mounted on a tire or wheel of the vehicle, and wirelessly communicating with a travel lane guide disposed on a road surface along the travel lane,
A determination means for determining a lateral travel position of the vehicle in the travel lane based on the result of the wireless communication;
Deviation control means for notifying the driver of a deviation state from the traveling lane of the vehicle based on the determination result by the determination means, or assisting steering of the vehicle,
A travel lane departure prevention device for a vehicle, comprising: A vehicle lane departure detection facility for detecting a vehicle lane departure from a lane provided on a road surface,
A traveling lane guide comprising an antenna for transmitting and receiving radio waves and a transmitting and receiving means for wirelessly communicating with an air pressure sensor mounted on a tire or wheel of a vehicle via the antenna, along the traveling lane on the road surface A vehicle lane departure detection facility characterized by being arranged at a predetermined interval.

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