JP5027748B2 - Vehicle travel safety device - Google Patents

Description

  The present invention relates to a vehicle travel safety device, and more specifically, to accurately determine a stationary object that has a low height such as a road fence (cat's eye) and does not hinder travel, and suppresses contact avoidance operation with the stationary object. Relates to the device.

  Transmits electromagnetic waves around the vehicle and detects objects such as a preceding vehicle from the reflected wave to determine the possibility of contact. When it is determined that there is a possibility of contact, avoid contact with an alarm device, etc. Various techniques for operating the support means have been proposed.

Among them, as described in Patent Document 1, when the variation in the reception level of the reflected wave at a short distance is small, the decrease rate of the reception level is small, or the reception level itself is small, the object is an empty can. For example, a technique has been proposed that suppresses the contact avoidance operation by determining that the object has a low height and does not interfere with traveling.
Japanese Patent No. 3966673

  The object of the present invention is to solve the same problems as in the prior art described above, and to accurately determine a stationary object such as a road fence that has a low height and does not interfere with traveling, and to suppress contact avoidance operation with it. An object of the present invention is to provide a traveling safety device for a vehicle.

In order to solve the above-mentioned object, according to claim 1, the electromagnetic wave is transmitted to the periphery of the vehicle at a predetermined time interval, and the object is detected based on the reflected wave obtained by reflecting the object. An object detection unit; a traveling state detection unit that detects a traveling state including a traveling speed of the host vehicle; and a relative distance between the host vehicle and the object based on a detection result of the object detection unit and the traveling state detection unit. Relative relationship calculating means for calculating a relative relationship consisting of speed, and a contact possibility determination for determining the possibility of contact between the own vehicle and the object according to a determination condition set based on the calculated relative relationship A vehicle travel safety device comprising: means and a support actuating means for actuating contact avoidance support means for assisting contact avoidance between the vehicle and the object when it is determined that there is a possibility of contact; Running the car A stationary object judging means for judging whether or not the object is a stationary object on the basis of a speed and a relative speed between the object and the judgment when the plurality of stationary objects are judged as the stationary object. Continuity determination means for determining presence / absence of continuity between the stationary objects, the plurality of stationary objects have a reflection level of the reflected wave equal to or higher than a first predetermined value, and the plurality of stationary objects are When it is determined that the width is equal to or less than the second predetermined value and has the continuity, the determination condition is changed to make it difficult for the contact possibility determination means to determine that there is a possibility of the contact. and a determination condition changing means, the continuity determining means, when said determined plurality of stationary object was there are three or more, positions consisting of the other distance and direction for two adjacent ones of which Calculating means for calculating a relationship; setting means for setting a predicted position based on the calculated separation distance and direction; and a predetermined range set based on the predicted position of the plurality of stationary objects. Determination means for determining whether or not a third stationary object exists, and when the determination means determines that the third stationary object exists within the predetermined range, the two stationary objects and from said third stationary object is configured as you determined to have continuity.

In the vehicle travel safety device according to claim 2 , the predetermined range is configured to be set according to the separation distance.

  In the vehicle travel safety device according to claim 1, the object is detected based on the reflected wave of the electromagnetic wave transmitted to the periphery of the own vehicle, the presence or absence of the possibility of contact with the own vehicle is determined, and the contact If it is determined that there is a possibility, the vehicle traveling safety device that activates the contact avoidance support means that supports contact avoidance determines whether or not the object is a stationary object, and there are a plurality of determined stationary objects. When determining whether or not there is continuity between stationary objects, each of the plurality of stationary objects has a reflection level equal to or higher than a first predetermined value, a width equal to or lower than a second predetermined value, and continuity. Then, when it is determined, it is configured to make it difficult to determine that there is a possibility of contact. Therefore, there is a possibility of contact with an object that does not hinder traveling such as a road fence (cat's eye). By making it difficult to determine Michibyo such that it is possible to suppress the contact avoidance operation in state before departing from the detection range of the object detection means, thus it is possible to better achieving both accurate contact avoidance and alarm excessive prevented.

  The above-described determination can also be realized by increasing the resolution in the height direction of the vehicle-mounted radar that is the object detection means. In this case, however, the structure of the radar is complicated and there is an inconvenience accompanied by an increase in cost. .

In addition , when there are three or more determined plurality of stationary objects, a positional relationship consisting of the other separation distance and direction with respect to one of the two adjacent objects is calculated, and based on the calculated separation distance and direction. And determining whether or not there is a third stationary object among a plurality of stationary objects within a predetermined range set based on the predicted position. Since the structure is such that the stationary object and the third stationary object are determined to have continuity, in addition to the effects described above, the presence or absence of continuity of the stationary object can be accurately determined, and the contact avoidance operation can be performed more reliably. Can be suppressed.

In the vehicle travel safety device according to the second aspect of the present invention, the predetermined range is configured so as to be set according to the separation distance. Therefore, in addition to the above effect, the detection error that increases as the separation distance increases is absorbed. Therefore, it is possible to more accurately determine the presence or absence of continuity of a stationary object.

  The best mode for carrying out a vehicle travel safety device according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram generally showing a vehicle travel safety device according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes a host vehicle (vehicle), and a four-cylinder internal combustion engine (shown as “ENG” in FIG. 1, hereinafter referred to as “engine”) 12 is mounted on the front portion thereof. The output of the engine 12 is input to an automatic transmission (shown as “T / M” in FIG. 1) 14. The automatic transmission 14 is a stepped type with 5 forward speeds and 1 reverse speed, and the output of the engine 12 is appropriately shifted there and transmitted to the left and right front wheels 16, driving the left and right front wheels 16, and the left and right rear wheels. 20 is driven and the vehicle 10 is driven.

  An alarm device 22 including an audio speaker and an indicator is provided in the driver's seat of the own vehicle 10, and when activated, the driver is warned by voice and vision. A brake pedal 24 disposed on the driver's seat floor of the host vehicle 10 includes brakes (disc brakes) mounted on the left and right front wheels 16 and the rear wheels 20 via a master back 26, a master cylinder 30 and a brake hydraulic mechanism 32, respectively. ) 34.

  When the driver operates (depresses) the brake pedal 24, the depressing force (depressing force) is increased by the master back 26, and the master cylinder 30 generates a braking pressure with the increased depressing force, via the brake hydraulic mechanism 32. Then, the brakes 34 attached to the front wheels 16 and the rear wheels 20 are operated to decelerate (brake) the vehicle 10.

  The brake hydraulic mechanism 32 includes an electromagnetic solenoid valve group inserted in an oil passage connected to a reservoir, a hydraulic pump, and an electric motor (all not shown) that drives the hydraulic pump. The electromagnetic solenoid valve group is connected to an ECU (Electronic Control Unit) 40 via a drive circuit (not shown).

  The ECU 40 includes a microcomputer including a CPU, a RAM, a ROM, an input / output circuit, and the like, and the four brakes 34 are operated independently of each other by the ECU 40 separately from the operation of the brake pedal 24 by the driver. Composed.

  In the above, the alarm device 22, the brake hydraulic mechanism 32 and the brake 34 correspond to contact avoidance support means, and the ECU 40 corresponds to a travel safety device including support operation means.

  A laser radar (laser scan radar) 42 is provided in front of the host vehicle 10. The output of the laser radar 42 is input to a radar output processing ECU (electronic control unit) 42a formed of a microcomputer.

  As shown in FIG. 2, the laser radar 42 emits laser light (transmits electromagnetic waves) toward the periphery (traveling direction) of the host vehicle 10 at a predetermined time interval, and exists around the host vehicle 10 (traveling direction). Receiving a reflected wave obtained by reflecting a laser beam on the object 100, that is, a preceding vehicle 100a parked on the shoulder, a road fence 100b buried along the center line of the road, a pedestrian 100c, or the like. Thus, the object 100 is detected.

  A road that is buried along the center line of the road when the host vehicle 10 travels from the center line or approaches the center line so as to avoid a preceding vehicle parked as indicated by an arrow. The cocoon 100b is easily detected. In FIG. 2, reference numeral 42 b indicates a laser beam of the laser radar 42. Although not shown, the laser beam 42b has a radial shape in the vertical (gravity) direction.

  FIG. 3 is a block diagram functionally showing the configuration of the radar output processing ECU 42a.

  As shown in FIG. 3, the radar output processing ECU 42a includes an object detection unit 42a1 and an object position calculation unit 42a2. The object detection unit 42a1 recognizes a line segment constituting the outline of the object based on an array of point groups obtained by projecting the reflection points onto a two-dimensional plane, and determines an end point of the object based on the recognized line segment. The object 100 such as the preceding vehicle 100a and the road fence 100b is detected by extraction.

  The object position calculation unit 42a2 calculates the position of the object 100 from the incident direction of the reflected wave obtained by emitting the laser light and the time until the reflected light is received. The output of the object position calculation unit 42a2 is sent to the ECU 40.

  In this specification, the “road fence” 100b is installed on the center line of the road lane marking, on the current basin, etc. at a certain interval and has a width (installation width) of 30 cm, 20 cm, 17 cm, etc. It is used to include all metal structures with a mark (also called “chatter bar” or “cat's eye”), and similar structures buried on roads such as botsdots.

  Returning to the description of FIG. 1, wheel speed sensors 46 are disposed in the vicinity of the front wheels 16 and the rear wheels 20, and output pulse signals for each predetermined rotation angle of each wheel. A steering angle sensor 52 is disposed in the vicinity of the steering wheel 50 provided in the driver's seat of the host vehicle 10, and generates an output proportional to the steering angle of the steering wheel input by the driver. Further, a yaw rate sensor 54 is disposed near the center position of the host vehicle 10 and generates an output corresponding to the yaw rate (angular velocity) around the gravity axis of the host vehicle 10.

  Outputs from the wheel speed sensor 46 and the like are sent to the ECU 40. The ECU 40 counts the outputs of the four wheel speed sensors 46 and calculates the average value thereof to detect the speed (traveling speed) V of the host vehicle 10.

  FIG. 4 is a flowchart showing the operation of the apparatus shown in FIG. The illustrated program is executed in the ECU 40 every predetermined time, for example, every 100 msec.

  In the following description, detection information of each sensor including the laser radar 42 is captured in S10, and the position and speed of the object 100 are calculated from the output of the object position calculation unit 42a2 of the radar output processing ECU 42a. Further, a traveling state such as a traveling speed of the host vehicle 10 is detected from the output of the wheel speed sensor 46.

  Next, in S12, the course of the host vehicle 10 is estimated (calculated) based on the traveling speed, the steering angle, and the yaw rate of the host vehicle 10.

  Next, in S14, when the object 100 exists on the calculated course, the relative relationship with the object 100 is calculated. That is, the output of the object position calculation unit 42a2 of the radar output processing ECU 42a is input, and the relative distance (relative position) from the own vehicle 10 to the object 100 and the relative speed of the object 100 with respect to the own vehicle 10 are calculated based on the input data. .

  Next, in S16, the predicted collision time T is calculated by dividing the calculated relative distance by the relative speed. The expected collision time T is a time estimated to be required until the vehicle 10 comes into contact with the object 100 when it is assumed that the driver does not take an avoiding action such as deceleration or a course change and the object 100 also travels as it is. It means a part of the determination condition set according to the calculated relative relationship.

  Next, in S18, it is determined whether or not the detected object 100 is a stationary object (hereinafter referred to as “100d”). This compares the calculated relative speed of the object 100 and the traveling speed of the host vehicle 10, and when the difference between the two is equal to or less than a predetermined value (for example, 20 km / h), the detected object 100 is determined to be a stationary object 100d ( judge.

  When the result is affirmative in S18, the process proceeds to S20, where it is determined whether or not there are a plurality of determined stationary objects 100d, and when the result is affirmed, the process proceeds to S22, where it is determined whether there are continuity of the plurality of stationary objects 100d. To do.

  FIG. 5 is a sub-routine flowchart showing the processing.

  Explained below, it is determined whether or not there are three or more stationary objects 100d determined in S100. If the determination is affirmative, the process proceeds to S102, and the other separation distance D1 with respect to one of the two adjacent ones is determined. A vector (D1, θ1) consisting of the direction θ1, that is, the positional relationship is calculated.

  FIG. 6 is an explanatory diagram for explaining the processing. Referring to the figure, when it is assumed that three stationary objects 100d1, 100d2, and 100d3 are detected as shown in the figure, the other two adjacent ones, for example, one of 100d1 and 100d2, the other 100d2 with respect to one 100d1. A vector composed of the separation distance D1 and the direction (angle) θ1 is calculated. The direction θ1 is an angle from the longitudinal axis of the own vehicle 10.

  Next, in S104, it is determined whether or not the direction θ1 is ± 15 degrees or less with respect to the longitudinal axis of the vehicle 10, and if affirmative, the process proceeds to S106 and the predicted position P is determined based on the calculated separation distance and direction. , That is, the predicted position P extended by the above-described vector starting from the other 100d2 is obtained.

  Next, in S108, it is determined (determined) whether or not the third stationary object 100d3 out of the three stationary objects 100d1, 100d2, and 100d3 exists within the predetermined range R set based on the predicted position P. .

  As shown in the figure, the predetermined range R is a set of four areas of 3 m in the front-rear direction and D1 × 0.1 + 1 m in the left-right direction. Thus, the predetermined range R is set according to the separation distance D1. This is because the detection error increases as the separation distance D1 increases, so that the detection error is absorbed.

  When the result in S108 is affirmative, the process proceeds to S110, in which it is determined that the two stationary objects 100d1 and 100d2 and the third stationary object 100d3 have continuity. Here, “having continuity” means being arranged at equal intervals (for example, 2 m to 5 m). If the determination at S104 and S108 is negative, the processing at S110 is skipped.

  Returning to the description of FIG. 4, the process then proceeds to S <b> 24, where the plurality of detected stationary objects 100 d have the reflection levels L of the reflected waves of the laser light being equal to or higher than the first predetermined value La, respectively, It is determined whether the width (installation width on the road, particularly the left-right width) W is equal to or smaller than the second predetermined value Wb and has continuity.

  Here, the reflection level is judged because the stationary object 100d is made of metal if it is a road fence 100b, so the reflection level is high, and its width is set to a prescribed value as described above. Because. Therefore, the first predetermined value La is set to a value sufficient to determine it. The second predetermined value Wb is also set to a value that is sufficient to discriminate the aforementioned road fence 100b.

  When the determination in S24 is affirmative and all three conditions are satisfied, it is determined that the detected plurality of stationary objects 100d are roadside objects 100b and do not hinder the traveling of the vehicle 10, and the process proceeds to S26. The threshold value Tai is changed to Taii. The threshold values Tai and Taii together with the expected collision time T constitute the above-described determination condition. Note that threshold value Tai> Taii. If the determination in S18, S20, or S24 is negative, the process up to S28 is skipped because it is not necessary to change the threshold value.

  Next, in S28, it is determined whether or not the expected collision time T is equal to or less than the threshold value Taii (or Tai), that is, the possibility of contact between the vehicle 10 and the object 100 according to the determination condition set according to the calculated relative relationship. It is determined whether there is.

  When the result in S28 is NO, the subsequent processing is skipped, and when the result is YES, the process proceeds to S30, and an alarm device that is a contact avoidance support unit that assists in avoiding contact with the object 100 by determining that the determination condition is satisfied. 22 and / or brake hydraulic mechanism 32 (and brake 34) are actuated to assist contact avoidance.

  In other words, in this embodiment, the expected collision time T expected to be required until the host vehicle 10 collides with the object 100 is calculated based on the calculated relative relationship, and the calculated expected collision time T is the threshold value Taii. (Or Tai) When it becomes below, it is judged that the judgment condition is established and it is judged that there is a possibility of contact, but when the result in S24 is affirmative, the object 100 is traveling of the host vehicle 10 Therefore, it is determined that the road fence 100b does not hinder.

  Therefore, in this case, the threshold value Tai is changed to a smaller value Tai in S26 to make it difficult to determine that there is a possibility of contact. Accordingly, it is possible to prevent the roadway 100b and the like from being erroneously determined to be in contact before being out of the detection range of the laser radar 42.

That is, the laser beam 42b of the laser radar 42 as mentioned above is detected since it is radial also in the vertical direction, is lower in height objects as road stud 100b by laser radar 42 when the vehicle 1 0 approaches thereto However, it is possible to prevent erroneous determination until then.

  In this embodiment, as described above, the object detection means (laser radar) detects the object 100 based on the reflected wave obtained by transmitting the electromagnetic wave to the periphery of the host vehicle 10 at a predetermined time interval and reflecting the object 100. 42, radar output processing ECU 42a, ECU 40, S10), traveling state detecting means (wheel speed sensor 46, ECU 40, S10, S12) for detecting a traveling state including the traveling speed of the host vehicle 10, the object detecting means and the Relative relationship calculating means (ECU 40, S14) for calculating the relative relationship between the relative distance and the relative speed between the vehicle 10 and the object 100 based on the detection result of the traveling state detecting means, and the calculated relative relationship Contact possibility determination means (ECU 40, S16 to S28) for determining whether or not the vehicle is in contact with the object according to the determination condition set based on the determination condition. When it is determined that there is a possibility of contact, a support operation that operates contact avoidance support means (alarm device 22, brake hydraulic mechanism 32 and brake 34) that supports contact avoidance between the vehicle and the object. In a vehicle travel safety device comprising means (ECU 40, S30), a stationary object determination for determining whether or not the object 100 is a stationary object 100d based on the traveling speed of the host vehicle 10 and the relative speed of the object 100 Means (ECU 40, S18) and continuity determination for determining the presence or absence of continuity between the determined stationary objects 100d when there are a plurality of determined stationary objects 100d and determined as the stationary object 100d Means (ECU 40, S20, S22, S100 to S110) and the plurality of stationary objects 100d each have a reflection level L of the reflected wave. The determination condition is more specific when it is determined that the plurality of stationary objects 100d is equal to or greater than one predetermined value La and the width W of each of the plurality of stationary objects 100d is equal to or smaller than the second predetermined value Wb and has the continuity. Includes determination condition changing means (ECU 40, S24 to S28) that changes a threshold value constituting a part of the determination condition and makes it difficult for the contact possibility determination means to determine that there is a possibility of contact. It was configured as follows.

  As described above, by making it difficult to determine that there is a possibility of contact with an object that does not hinder driving such as a road fence (cat's eye) 100b, the road fence 100b and the like are detected by the laser radar. Contact avoidance operations such as alarms and brakes before deviating from the area can be suppressed, and both prevention of excessive alarms and accurate contact avoidance can be achieved at the same time.

  Further, when there are three or more of the determined plurality of stationary objects 100d, the continuity determination means has a positional relationship consisting of a separation distance D1 of the other 100d2 with respect to two adjacent ones 100d1 and a direction θ1. Is calculated based on the predicted position P, setting means (S104, S106) for setting the predicted position P based on the calculated separation distance D1 and direction θ1, and setting the predicted position P. Determination means (S108) for determining whether or not a third stationary object 100d3 of the plurality of stationary objects exists within a predetermined range R, and the third means within the predetermined range by the determination means. When it is determined that there are still objects, the two stationary objects and the third stationary object are determined to have continuity (S110). Thus, in addition to the effects described above, the presence or absence of continuity of the stationary object 100d can be accurately determined, and the contact avoidance operation can be more reliably suppressed.

  Further, since the predetermined range R is configured to be set according to the separation distance D1, in addition to the above-described effects, it is possible to absorb a detection error that increases as the separation distance D1 increases, and the stationary object 100d. The presence or absence of continuity can be determined more accurately.

  In place of or in addition to the process of S30 in the flowchart of FIG. 4, the driver's seat (not shown) of the vehicle 10 is vibrated by an appropriate means, or a seat belt (not shown) is pulled in. Also good.

  Although the object 100 is detected from the output of the laser radar 42, a millimeter wave radar may be used instead of or in addition thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an overall traveling safety device for a vehicle according to an embodiment of the present invention. It is explanatory drawing which shows the object detection by the laser radar shown in FIG. FIG. 2 is a block diagram functionally showing the configuration of a radar output processing ECU shown in FIG. 1. It is a flowchart which shows operation | movement of the apparatus shown in FIG. FIG. 4 is a sub-routine flow chart showing a process for determining whether or not a plurality of stationary objects are continuous in the flow chart of FIG. 4. 5 is an explanatory diagram for explaining the processing of the flow chart.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Vehicle (own vehicle), 12 Engine (internal combustion engine), 16 Front wheel, 20 Rear wheel, 22 Alarm device, 34 Brake, 36 Brake switch, 40 ECU (electronic control unit), 42 Laser radar, 42a Radar output processing ECU, 42a1 object detection unit, 42a2 object position calculation unit, 42b laser beam, 46 wheel speed sensor, 100 object, 100a preceding vehicle, 100b roadside, 100c pedestrian, 100d stationary object

Claims (2)

An electromagnetic wave is transmitted to the periphery of the vehicle at a predetermined time interval, and an object detection means for detecting the object based on a reflected wave obtained by reflecting the object and a traveling state including a traveling speed of the own vehicle are detected. A traveling state detecting unit; a relative relationship calculating unit that calculates a relative relationship between a relative distance and a relative speed between the vehicle and the object based on detection results of the object detecting unit and the traveling state detecting unit; Contact possibility determination means for determining the possibility of contact between the vehicle and the object according to the determination condition set based on the relative relationship, and when it is determined that there is a possibility of the contact, A travel safety device for a vehicle, comprising a support actuating means for actuating contact avoidance assisting means for assisting contact avoidance between the host vehicle and the object, based on a travel speed of the host vehicle and a relative speed of the object. Object A stationary object determining means for determining whether or not the object is a stationary object, and a continuous object for determining whether or not there is continuity between the determined stationary objects when there are a plurality of determined stationary objects and the stationary object is determined. The plurality of stationary objects each have a reflection level of the reflected wave equal to or greater than a first predetermined value, and the plurality of stationary objects each have a width equal to or less than a second predetermined value, A determination condition changing unit that, when determined to have continuity, changes the determination condition to make it difficult for the contact possibility determination unit to determine that there is a possibility of contact, and the continuity determination unit includes: , When there are three or more of the determined plurality of stationary objects, a calculating means for calculating a positional relationship consisting of a distance and direction of the other of two adjacent ones, and the calculated distance Determining means for setting a predicted position based on the direction, and determining whether or not a third stationary object among the plurality of stationary objects exists within a predetermined range set based on the predicted position And the two stationary objects and the third stationary object are determined to have continuity when it is determined by the determining means that the third stationary object exists within the predetermined range. running safety device for a vehicle according to claim to Rukoto. Wherein the predetermined range, the travel safety device for a vehicle according to claim 1, characterized in that it is set according to the distance.

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