Driving assistance device and method for motor vehicle

Abstract

The driving assistance device (58) for a motor vehicle (2) comprises: a line detector (60, 62) for detecting a boundary line on a lane; a setting module (64) capable of setting a virtual lane according to the detected line; and a monitoring module (68) capable of monitoring the risk of the motor vehicle leaving the set virtual lane. The device comprises a module (74) for acquiring an image representing an object of interest, the setting module (64) comprising a first map (90, 96) containing values ​​of the virtual lane boundary position depending on the lateral offset of the object of interest in the acquired image.

Description

Technical Field

[0001] The present invention relates to the field of driving assistance devices and methods for motor vehicles, and more particularly to devices and methods aimed at limiting the risk of the vehicle leaving its lane on a road. Background Art

[0002] Some motor vehicles are provided with a lane departure warning (LDW) system. The function of the LDW system is to compare the actual trajectory of the vehicle with the boundary lines of the lane on the road to detect the risk of the vehicle leaving the lane and warn the driver of this risk as required. In addition, these same vehicles or other motor vehicles are provided with a lane keeping aid (LKA) system. The LKA system differs from the LDW system in that it acts on the directional control of the vehicle to correct the trajectory of the vehicle. The general expression "driving assistance device" is used in this application to refer to LDW systems and LKA systems.

[0003] If the road is poorly maintained or the border lines of the lanes on the road are not repainted frequently enough, these lines may not exist or be so difficult to see that they cannot be detected. In this case, the conventional driving assistance equipment is automatically deactivated. In this way, in the case of LDW systems, the generation of false driver warnings is prevented, and in the case of LKA systems, undue interference with the vehicle trajectory is prevented. The deactivation of the driving assistance equipment is accompanied by the display of a warning light to inform the driver that the equipment is not available.

[0004] This solution is not entirely satisfactory because illuminating the warning light may cause the driver to panic, and deactivating the driver assistance device may negatively impact the safety of the vehicle occupants. Summary of the invention

[0005] In view of the above, an object of the present invention is to overcome the above-mentioned disadvantages associated with driving assistance devices.

[0006] More specifically, an object of the present invention is to ensure operation of a driving assistance device even when a boundary line on a lane cannot be detected.

[0007] To this end, a driving assistance device for a motor vehicle is proposed, which includes: a line detector, which is used to detect boundary lines on a lane; a setting module, which can set a virtual lane based on the detected line; and a monitoring module, which can monitor the risk of the motor vehicle leaving the set virtual lane.

[0008] According to one of the general characteristics of the invention, the device comprises an acquisition module for acquiring an image representing the relevant object, and the setting module comprises a first map containing values ​​of the virtual lane boundary position depending on the lateral offset of the relevant object in the acquired image.

[0009] Therefore, the device is made more robust. Specifically, the device can operate even when the boundary line on the lane cannot be detected.

[0010] In the present application, the term "image" is understood to be a representation of a given real object produced by an optical system. The image comprises in particular tracks, which may be tracks identified by radar echoes or tracks identified by detection by a camera.

[0011] According to one embodiment, the settings module further comprises a second map containing values ​​of virtual lane widths depending on the country in which the vehicle is travelling.

[0012] Since the second map is very simple and the invention does not require the addition of components other than software, the robustness of the device is increased at a low cost.

[0013] In another embodiment, the first map is configured to deliver values ​​of virtual lane boundary positions derived by applying the following relationship:

[0014] lim 相邻 =y / 2,

[0015] lim 相反 =-lim 相邻 ,

[0016] Among them, lim 相邻 is the relative position of the virtual lane boundary on the side adjacent to the relevant object with respect to the transverse symmetry plane of the motor vehicle;

[0017] lim 相反 is the relative position of the virtual lane boundary on the side opposite to the object concerned with respect to the transverse symmetry plane, and

[0018] y is the lateral offset of the object of interest relative to the acquisition module.

[0019] Advantageously, the first map is configured to modify the value of the relative position of the virtual lane boundary on the side opposite to the relevant object relative to the transverse symmetry plane (preferably, to increase its absolute value) in the following circumstances: when the absolute value of the corresponding position of the virtual lane boundary on the side adjacent to the relevant object relative to the transverse symmetry plane decreases at a rate of change below a predefined threshold; and / or when the sum of the absolute values ​​of these virtual lane boundaries is less than a predefined safety amount.

[0020] In one embodiment, the acquisition module is configured to acquire a plurality of images representing the object of interest, and the device comprises a selector module for selecting a minimum lateral offset of the object of interest across the acquired plurality of images.

[0021] Configuring the acquisition module in this manner avoids having to subject the device to potential fluctuations of the moving vehicle constituting the object of interest.

[0022] A measurement module may also be provided, the measurement module being used to measure the curvature of the roadside, and the first map transmits respective values ​​of the virtual lane boundary positions derived from the curvature measured by the measurement module.

[0023] This feature allows the device to operate optimally when the motor vehicle is turning.

[0024] A calculator module may also be provided for calculating a time to collision with a related object, and the setting module is configured to input a lateral offset of a related object with a shortest collision time into the first map when multiple related objects are available.

[0025] These features reduce the risk of collision with other vehicles. In addition, if the acquisition module is able to capture images of relevant objects located relatively far in front of the vehicle, the risk of collision with oncoming vehicles in adjacent lanes is reduced.

[0026] An identifier module may also be provided, the identifier module being capable of detecting a change in the lateral offset of the first curb relative to the second curb.

[0027] An identifier module such as this makes it possible to identify a section in which the number of lanes increases (such as a section changing from two lanes to three lanes), or a section in which the number of lanes decreases (such as a section changing from three lanes to two lanes).

[0028] In one embodiment, the setup module is configured to interpolate the lateral offset of the associated object between a start of the segment and an end of the segment when the identifier module detects a segment in which the number of lanes decreases.

[0029] In one embodiment, the setting module is configured to prohibit the device from operating between the start increase and the end increase of the section when the identifier module detects a section in which the number of lanes increases.

[0030] According to another aspect, a driving assistance method for a motor vehicle is provided, wherein a boundary line on a driving lane is detected; a virtual lane is set based on the detected line; and the risk of the motor vehicle leaving the set virtual lane is monitored. If the boundary line cannot be detected, an image of a relevant object is acquired and a virtual lane is set based on the position of the relevant object in the acquired image. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Other objects, features and advantages of the present invention will become clear from a reading of the following description, given by way of non-limiting example only and with reference to the accompanying drawings, in which:

[0032] - Figure 1 is a schematic view of a motor vehicle incorporating a driving assistance device according to an aspect of the invention;

[0033] - Figure 2 yes Figure 1 Schematic representation of the auxiliary equipment of the vehicle;

[0034] - Figure 3 Schematically shows Figure 1 The vehicle is in the first operating condition;

[0035] - Figure 4 Schematically shows Figure 1 The vehicle is in the second operating condition;

[0036] - Figure 5 Schematically shows Figure 1 The vehicle is in the third operating condition;

[0037] - Figure 6 Schematically shows Figure 1 The vehicle is in the fourth operating condition;

[0038] - Figure 7 Schematically shows Figure 1 of the vehicles are in the fifth operating condition; and

[0039] - Figure 8 A driving assistance device according to a variant embodiment of the present invention is shown. DETAILED DESCRIPTION

[0040] refer to Figure 1 , schematically showing a motor vehicle 2 traveling on a road 4. A direct orthogonal vector basis 6 associated with the road 4 is defined. The basis 6 consists of vectors Vector and vector Composition. Vector is oriented vertically upwards relative to the road 4. The vector and Contained in a plane that is horizontal to the road 4. Vector It is longitudinal to the road 4. Vector It is transverse to the road 4.

[0041] In this application, the reference vector The terms "in front of" and "behind" are to be understood in relation to the direction and orientation of The terms "lateral", "crosswise", "left-hand", and "right-hand" are to be understood in relation to the orientation and direction of the left-hand side. The tail side corresponds to the right hand side, while the vector One side of the head corresponds.

[0042] The road 4 is laterally delimited by a left-hand curb 8 and a right-hand curb 10 .

[0043] The road 4 is divided into three lanes in the transverse direction, in this example, a left-hand lane 12, a middle lane 14 and a right-hand lane 16. Lanes 12 and 14 are bounded by a boundary line 18. Lanes 14 and 16 are bounded by a boundary line 20. In the example shown, boundary lines 18 and 20 are white dashed lines. However, different boundary lines can be envisioned, for example, lines composed of solid white lines, lines with different colors or other discontinuous shapes. Similarly, the present invention is not limited to the number of lanes shown in the accompanying drawings.

[0044] The vehicle 2 comprises a vehicle body 22, an onboard computer 24, a directional control device 26 and a driver interface 28. The vehicle 2 further comprises a global navigation satellite system (GNNS) 30, such as, for example, a global positioning system (GPS). The vehicle 2 comprises a module 32 for inputting a country in which the vehicle is travelling. The module 32 allows an operator, such as a mechanic responsible for servicing the vehicle 2, to input a country in which the vehicle 2 is intended to travel.

[0045] The vehicle 2 further includes a front radar 34, a front camera 36, ​​and four corner radars 38, 40, 42, and 44. The components 34, 36, 38, 40, 42, and 44 enable the acquisition of Figure 1 The image of the surroundings of the vehicle 2 in a specific area delimited by the dotted line in FIG. In order to enhance the clarity of the drawings, the images are intentionally shown in an adjusted scale. Figure 1 In addition, the positions of components 34, 36, 38, 40, 42 and 44 are schematic, and different positions may be envisioned for these components without departing from the scope of the present invention.

[0046] More specifically, the function of the radar 34 is to detect targets located in front of the vehicle 2. The radar 34 makes it possible to specifically detect targets located relatively far from the vehicle 2. These targets may specifically include other vehicles traveling on the road 4, road signs or other obstacles. To this end, the radar 34 is positioned in the grille (not shown) of the vehicle so as to view a collection area 46 located in front of the vehicle 2. Similarly, the radar 34 can be positioned behind a subsurface (such as a bumper or a holographic logo). The area 46 is defined by a dotted line formed by a series of long dashes. The range of the radar 34 is between 200m and 300m, preferably substantially 250m.

[0047] The function of the camera 36 is to detect and track the curbs 8 and 10. The camera 36 is positioned on the front edge of the roof of the vehicle or in the upper central area of ​​the windshield to capture images in a capture area 48 which is located in the middle of the vehicle. Figure 1 4 is schematically delimited by a series of dots in the figure. The acquisition area 48 is mainly located in front of the vehicle 2. The area 48 is delimited by a dotted line formed by a series of short dashes. The range of the front camera 36 is between 100m and 150m, preferably about 125m. However, without departing from the scope of the present invention, cameras other than the camera 36 may be used, for example, a camera having a range of about 200m. Multiple cameras covering the front and rear of the vehicle 2 therebetween may also be used.

[0048] The function of the radars 38, 40, 42 and 44 is to detect targets at a relatively close or medium distance relative to the vehicle 2. These targets may specifically be other vehicles traveling on the road 4. The radars 38, 40, 42, 44 collect images in corresponding collection areas 50, 52, 54, 56, which are located in the vehicle 2. Figure 1 2 is schematically represented by a series of dashed lines formed by alternating long and short dashes. Radar 38 is positioned at the left front corner of vehicle body 22. Radar 40 is positioned at the right front corner of vehicle body 22. Radar 42 is positioned at the left rear corner of vehicle body 22. Radar 44 is positioned at the right rear corner of vehicle body 22. Radars 38 and 40 have a range of about 80m to 100m in the front, preferably about 90m in the front, and a range of 30m to 50m to the side, preferably about 40m to the side. Similarly, radars 42 and 44 have a range of about 80m to 100m in the rear, preferably about 90m, and a range of 30m to 50m to the side, preferably about 40m.

[0049] The invention is not limited to this choice of image acquisition means. According to a particular variant, a trifocal camera can be used, comprising a first sensor with an aperture angle of 28° and a range of 180 m, a second sensor with an aperture angle of 52° and a range of 120 m, and a third sensor with an aperture angle of 150° and a range of 60 m.

[0050] The vehicle 2 includes a driving assistance device 58 . Figure 2 The device 58 is shown in FIG. The driving assistance device 58 performs both the LDW function and the LKA function. However, it is of course possible to envisage a driving assistance device that implements only one of these two functions without departing from the scope of the present invention.

[0051] The device 58 includes a detector for detecting a left-hand line 60 and a detector for detecting a right-hand line 62. The detectors 60 and 62 are line recognition sensors that are positioned on the left-hand side and the right-hand side of the vehicle body 22, respectively. Accordingly, the detectors 60 and 62 are capable of detecting the presence and position of the corresponding lines 18 and 20 relative to the vehicle body 22. Although specific sensors for detecting the lines 18 and 20 are provided in the illustrated example, the radar 34, 38, 40, 42, 44 or the camera 36 may be used to detect the presence and position of the lines 18 and 20 without departing from the scope of the present invention. In the case where multiple of these acquisition or detection devices are used to detect the presence and position of the lines 18 and 20, information redundancy allows the robustness of the device 58 to be improved. If the detector 60 is unable to detect the boundary line on the lane, it transmits a signal IMP 60 Similarly, if the detector 62 cannot detect the boundary line on the lane, it transmits a signal IMP 62 .

[0052] The device 58 comprises a setting module 64. The function of the module 64 is to set a virtual lane for the vehicle 2 based on the available information. To achieve this, the module 64 comprises a first calculator 66 having a data link to the detectors 60 and 62. The calculator 66 is able to determine the values ​​of the two boundary positions of the virtual lane based on the information collected. A second calculator 67 has a data link to the calculator 66 and the on-board computer 24 in order to receive the moving speed of the vehicle 2 and the actuation of the turn indicator of the vehicle 2. The calculator 67 compiles the collected information in order to verify whether the vehicle 2 is deviating from the virtual lane (this is not intentional by the driver). If this is indeed the case, there is a risk that the vehicle 2 deviates from the lane 14, and the calculator 67 transmits a warning signal. In order to verify the risk of deviating from the virtual lane, the calculator 67 can compare the trajectory followed by the vehicle 2 with the virtual lane boundary in a manner known per se.

[0053] The device 58 comprises a monitoring module 68. The module 68 comprises a warning block 70 and a correction block 72. The blocks 70 and 72 have a data link to the calculator 67. The function of the block 70 is to actuate a warning light on the driver interface 28 when the calculator 67 transmits a warning signal. The function of the block 72 is to modify the trajectory followed by the vehicle 2 when the calculator 67 transmits a warning signal so as to eliminate the risk of the vehicle 2 leaving the lane 14. To this end, the block 72 is provided with hardware and software means for: generating a corrected direction setpoint; and transmitting the corrected direction setpoint to the direction control device 26.

[0054] The device 58 includes an acquisition module 74. The module 74 includes the radar 34, the camera 36, ​​and the radars 38, 40, 42, and 44. Accordingly, the module 74 is capable of acquiring multiple images of the vehicle's surroundings in the acquisition areas 46, 48, 50, 52, 54, and 56 within a given period of time. In doing so, the module 74 builds a multi-sensor model.

[0055] The device 58 comprises a measuring module 75. The module 75 has a data link to the camera 36. The module 75 is provided with hardware and software means for determining whether the road 4 has a curve; and if so, measuring the radius of curvature R of the roadside 8. 8 and the curvature radius R of the roadside 10 10 In addition, module 75 calculates the radius R 8 and R 10 The average value R 8-10 If the road 4 does not have a curve, the module 75 transmits a signal IMP 75 .

[0056] The device 58 comprises a calculator module 76. The module 76 has a data link to the module 74, the onboard computer 24 and the direction control device 26. The function of the module 76 is to calculate the collision time TTC between the vehicle 2 and the object x, regardless of the nature of the object x detected by the acquisition module 74 (for example, an obstacle or another vehicle). x .

[0057] The device 58 comprises an identifier module 78. The module 78 has a data link to the module 74. More specifically, the module 78 receives the relative positions of the curbs 8 and 10 relative to the vehicle body 22. Thus, the module 78 is able to detect an increase or decrease in the distance between the curb 8 and the curb 10 and therefore a section of the road 4 in which the number of lanes increases or a section of the road 4 in which the number of lanes decreases. According to a variant, the module 78 can receive information about the section of the road 4 in which the number of lanes increases or decreases from the integrated map and / or from the system 30.

[0058] Module 64 includes a minimum block 80. Block 80 has a data link to modules 74 and 76. Block 80 receives images acquired by module 74 representing relevant objects. The represented relevant objects may be, for example, another motor vehicle traveling on road 4, an obstacle or a road sign. The collision time calculated by module 76 is associated with each relevant object. Block 80 selects those images representing relevant objects having the shortest collision time.

[0059] The module 64 comprises a calculation device 82. The function of the device 82 is to measure the lateral displacement y of the object of interest across the image selected by the block 80. In this case, the relative displacement y is relative to the plane of symmetry P of the vehicle body 22. 对称 (not shown) perpendicular to the vector to measure.

[0060] The module 64 comprises a selector module 84. The module 84 is provided with hardware and software means for performing the following operations: selecting the minimum value of the offset y calculated by the device 82 within a predetermined duration. The predetermined duration can be calibrated according to driver experience, performance and robustness. In the example shown, the predetermined duration is between 0.5 seconds and 1.5 seconds, and is preferably about one second.

[0061] The module 64 comprises an interpolation block 86. The block 86 has a data link to the modules 84 and 78. The function of the block 86 is to identify the normal value of the lateral offset of the object of interest in the case of a reduction in the number of lanes on the road 4. To this end, if the module 78 does not detect a section in which the number of lanes is reduced, the block 86 delivers the value of the offset y. If a section in which the number of lanes is reduced is detected, the block 86 transfers the value y 内插 Added to the offset y. When the segment starts to decrease, the value y 内插 At the end of this segment, the value y 内插 is equal to the value of offset y at the beginning of the segment. Between the beginning and end of the segment, the value y 内插 The signal corresponding to the possible modified lateral offset delivered by block 86 is determined by interpolating between its value at the beginning of the segment and its value at the end of the segment. 2 To express.

[0062] Module 64 includes an inhibitor block 88. Block 88 has data links to block 86 and module 78. The function of block 88 is to inhibit operation of device 58 when the vehicle is traveling through a section in which the number of lanes is increased. To this end, if module 78 does not detect a section in which the number of lanes is increased, block 88 transmits an offset y 2 Otherwise, block 88 transmits an error value, thereby disabling device 58 and activating a warning light on driver interface 28.

[0063] The module 64 comprises a map 90 containing the information dependent on the offset y 2 The boundary position value lim 相邻 and lim 相反。 Location 相邻 and lim 相反 Corresponding to the transverse plane P 对称 The relative virtual lane boundary. Position value lim 相邻 The virtual lane boundary corresponding to the side adjacent to the object in question. Position value lim 相反 The virtual lane boundary corresponds to the side opposite to the object of interest. The map 90 has data links to the block 88 , the detectors 60 and 62 , and the module 75 .

[0064] Map 90 is configured to deliver a value only if both detectors 60 and 62 are unable to detect lines 18 and 20. To this end, only the detection signal IMP delivered by detector 60 60 and the detection signal IMP transmitted by the detector 62 62 Without departing from the scope of the present invention, it is conceivable that the map 90 transmits a value as long as one of the detectors 60 and 62 is unable to detect the line. In this case, only one signal IMP 60 or IMP 62 The value is passed when it is entered into the map 90.

[0065] When the signal IMP 60 、IMP 62 、IMP 75 and 2 When input to map 90, the map passes the value lim obtained by applying the following relationship 相邻 and lim 相反 :

[0066] lim 相邻 =y 2 / 2, and

[0067] lim 相反 =-lim 相邻 .

[0068] In the example shown, the map 90 is configured to take into account the risks associated with the deviation of the vehicle constituting the object of interest, or the different fluctuations of the virtual lane boundary. More specifically, the map 90 is configured to deliver different values ​​lim if at least one of the following conditions is met: 相邻 and lim 相反 :

[0069] |y 2|<w 车辆 +2.w cal ,

[0070] or

[0071] |lim 相邻 |+|lim 相反 |<w voie_最小 ,

[0072] Among them, w 车辆 is the width of the motor vehicle, w cal and w voie_最小 is a predefined safety amount, and var is a predefined negative rate of change. and |lim 相邻 |+|lim 相反 |Corresponds to the width of the virtual lane set by module 64.

[0073] If |y2|<w 车辆 +2.w cal , then map 90 transmits an erroneous value, thereby disabling device 58 and activating a warning light on driver interface 28 .

[0074] If |y2|>w 车辆 +2.w cal And d / dt(|lim 相邻 |)<var, then map 90 will set the boundary value lim 相反 is replaced by the new value calculated by applying the following equation:

[0075]

[0076] Among them, w voie is a predefined value or a value delivered by a map (not shown) containing standard widths of road lanes depending on the country in which the vehicle is travelling.

[0077] If |y2|>w 车辆 +2.w cal And|lim 相邻 |+|lim 相反 |<w voie_最小 , then map 90 will be the boundary value lim 相反 is replaced by the new value calculated by applying the following equation:

[0078] |lim 相反 |=-|lim 相邻 |+w voie ,

[0079] sign(lim 相反 )=-sign(lim 相邻 )

[0080] Among them, w voie is a predefined value or a value delivered by a map (not shown) containing standard widths of road lanes depending on the country in which the vehicle is travelling.

[0081] If the map receives a radius R 8-10 Instead of signal IMP 75 , then the map calculates the value lim by applying the above equation 相邻 and lim 相反 And modify these values ​​so that the virtual lane boundary appears equal to the radius R 8-10 The radius of curvature.

[0082] refer to Figure 3 , the vehicle 2 is schematically shown in a first operating situation. Identical elements have the same reference numerals.

[0083] Another motor vehicle 100 is travelling in a lane 12 on the road 4 ahead of the vehicle 2. Essentially at the longitudinal position of the vehicle 2, the lines 18 and 20 are not visible on the road 4.

[0084] In this operating condition, the module 74 (in this example, the camera 36 and the radar 38) collects an image representing the vehicle 100. At the same time, the detectors 60 and 62 transmit the signal IMP 60 and IMP 62 . The calculator 66 is then deactivated. Since the road 4 is straight, the module 75 transmits the signal IMP 75 The image acquired by module 74 is transmitted by block 80 to module 82. Module 82 calculates the lateral offset y of vehicle 100 relative to vehicle 2 100 . Signal y 100 、IMP 60 、IMP 62 and IMP 75 The value lim is transmitted to the transfer value lim via blocks 86 and 88. 相邻 and lim 相反 Map 90. Value lim 相邻 and lim 相反 It is transmitted to the calculator 67 which sets the virtual lane 102 and then determines whether the vehicle 2 is deviating from the virtual lane 102 (which is not the driver's intention). If the vehicle 2 is deviating from the virtual lane 102, a warning signal is sent to blocks 70 and 72 which implement warning actions and corrective actions.

[0085] refer to Figure 4 , the vehicle 2 is schematically shown in a second operating situation. Identical elements have the same reference numerals. Figure 3Compared with the case of , the trajectory of vehicle 100 is affected by the fluctuation. 100 Under these conditions, module 84 determines the minimum lateral deviation y within a predetermined duration. 100_最小 . Then, refer to Figure 3 Use offset y 100_最小 To determine the value of lim 相邻 and lim 相反 Therefore, fluctuations in the trajectory of the vehicle 100 do not affect the boundaries of the virtual lane 102 .

[0086] refer to Figure 5 , the vehicle 2 is schematically shown in a third operating situation. The same elements have the same reference numerals. Figure 3 Compared to the case of , road 4 includes a left turn. Therefore, module 75 no longer transmits the signal IMP 75 Instead, module 75 measures the radius R 8 and R 10 And calculate the radius R 8-10 . Set the radius R 8-10 is input into the map 90. Therefore, the radius of curvature of the virtual lane 102 boundary is modified to correspond to the radius R 8-10 .

[0087] refer to Figure 6 , the vehicle 2 is schematically shown in a fourth operating situation. The same elements have the same reference numerals. Figure 3 Compared to the situation of FIG. 1 , the third vehicle 104 is traveling on the road 4. The vehicle 104 is traveling in the lane 16, encroaching on the boundary line 20. Because of this, the lateral offset y of the vehicle 104 104 (in absolute value) is smaller than the offset y 100 The speed of vehicle 104 is slightly higher than that of vehicle 2, while the speed of vehicle 100 is substantially equal to that of vehicle 2. Accordingly, module 76 calculates the time to collision TTC of vehicle 104 104 , which is shorter than the collision time TTC of vehicle 100 100 Thus, the minimum block 80 selects only the image representing the vehicle 104. Therefore, the computing device 82 does not take into account the lateral offset y 100 , and only according to the offset y 104 To establish the value lim 相邻 and lim 相反 .

[0088] refer to Figure 7 , the vehicle 2 is schematically shown in a fifth operating situation. Identical elements have the same reference numerals. Figures 3 to 6The vehicle 100 has been replaced by a vehicle 106 approaching in the opposite direction. The vehicle 106 is traveling in the lane 12 on the road 4. The vehicle 106 is traveling along the vector Although the distance between vehicle 106 and vehicle 2 is relatively large compared to the distance between vehicle 104 and vehicle 2, and the lateral offset y associated with vehicle 106 106 (in absolute terms) less than the lateral displacement y 104 , but since vehicle 104 is traveling in the opposite direction, the time to collision TTC associated with vehicle 106 is 106 Time to Collision TTC 104 Thus, block 80 will select only images representing vehicle 106 .

[0089] refer to Figure 8 , schematically shows a driving assistance device 94 according to a second embodiment of the present invention. Identical elements have the same reference numerals. Specifically, the device 94 can be incorporated into the vehicle 2 instead of the device 58.

[0090] Device 94 differs from device 58 in that map 90 is replaced by two maps 96 and 98. Map 96 passes neighboring position values ​​lim in the same way as map 90 相邻 .map96 does not pass the opposite position value lim 相反 The map 98 has a data link to the input module 32. In particular, the map 98 receives information from the module 32 about the country in which the vehicle 2 is travelling. The map 98 contains virtual lane width values ​​that depend on the country in which the vehicle is travelling. In particular, the virtual lane width is determined according to the standard width of the roadway in the country in which the vehicle 2 is travelling. In this way, the map 98 delivers a virtual lane width w obtained by applying the following relationship voie and the opposite position value lim 相反 :

[0091] │lim 相反 │=-│lim 相邻 │+w voie And sign(lim 相反 )=-sign(lim 相邻 ).

[0092] According to a variant of this second embodiment, the map 98 receives information from the GPS 30 about the country in which the vehicle 2 is travelling.

[0093] In view of the above, the driving assistance device according to the present invention can continue to provide the LDW function and / or the LKA function even when the boundary line on the lane cannot be detected. This improvement to the driving assistance device does not require the addition of any special components other than software components. Therefore, this improvement can be implemented at a particularly low cost.

Claims

1. A driving assistance device (58, 94) for a motor vehicle (2), the device comprising: A line detector (60, 62) for detecting a boundary line on a lane (12, 14, 16); A setting module (64) capable of setting a virtual lane (102) based on the detected lines (18, 20); a monitoring module (68) capable of monitoring the risk of the motor vehicle (2) leaving the set virtual lane (102), characterized in that the device includes a collection module (74) for collecting images representing relevant objects (100, 104, 106), the setting module (64) includes a first map (90, 96), the first map containing the boundary position (lim) of the virtual lane (102) 相邻 ,lim 相反 ), the value of the virtual lane boundary position depends on the lateral offset (y) of the relevant object relative to the motor vehicle in the acquired image 100 ,y 104 ,y 106 ), wherein the acquisition module (64) is configured to acquire a plurality of images representing the object of interest (100, 102, 104), the device (58) comprising a selector module (84) for selecting a minimum lateral offset of the object of interest (100, 104, 106) relative to the motor vehicle from among the plurality of acquired images; The first map (90) is configured to transmit the virtual lane (102) boundary position (lim) obtained by applying the following relationship: 相邻 ,lim 相反 ) value: lim 相邻 =y / 2, glue 相反 =-glue 相邻 , Among them, lim 相邻 is the relative position of the boundary of the virtual lane (102) on the side adjacent to the relevant object (100, 104, 106) relative to the transverse symmetry plane of the motor vehicle (2); lim 相反 is the relative position of the boundary of the virtual lane (102) on the side opposite to the associated object (100, 104, 106) with respect to the transverse symmetry plane, and y is the lateral offset of the relevant object relative to the acquisition module; The first map (90) is configured to modify a boundary position (lim) of a virtual lane (102) on the opposite side to the relevant object (100, 104, 106) in the following circumstances: 相反 ) value: the boundary position (lim) of the virtual lane (102) on the side adjacent to the relevant object (100, 104, 106) 相邻 ) decreases at a rate lower than a predefined threshold (var); or at the boundary of the virtual lane (lim 相邻 ,lim 相反 ) is less than the predefined safety value (w voie_最小 )hour.

2. The device (94) of claim 1, wherein: The setting module (64) further comprises a second map (98) containing values ​​of virtual lane widths (w voie ).

3. The device (58, 94) of claim 1 or 2, further comprising: A measuring module (75) for measuring the curvature of the roadside (8, 10), wherein the first map (90) transmits a curvature (R) depending on the curvature (R) measured by the measuring module (75) 8-10 ) of the virtual lane (102) boundary position (lim 相邻 ,lim 相反 ) values.

4. The device (58, 94) of claim 1 or 2, further comprising: A calculator module (76) for calculating a time to collide with a related object (100, 104, 106), wherein the setting module (64) is configured to set a lateral offset (y) of a related object (104, 106) with a shortest collision time when multiple related objects (100, 104, 106) are available. 104 ,y 106 ) is input into the first map (90).

5. The device (58, 94) of claim 1 or 2, comprising: An identifier module (78) is capable of detecting a change in the lateral offset of a first curb (8, 10) relative to a second curb (10, 8).

6. The device (58, 94) of claim 5, wherein: The setting module (64) is configured to interpolate the lateral offset of the relevant object (100, 104, 106) between the start and end of the segment when the identifier module (78) detects a segment in which the number of lanes decreases, and / or the setting module (64) is configured to prohibit the device (58) from operating between the start and end of the segment when the identifier module (78) detects a segment in which the number of lanes increases.

7. A driving assistance method for a motor vehicle (2) implemented by means of a device as claimed in any one of claims 1 to 6, wherein: - detecting the boundary lines (18, 20) of the lanes (12, 14, 16), - setting a virtual lane based on the detected line (18, 20), - monitoring the risk of the motor vehicle (2) leaving the virtual lane provided, The invention is characterized in that if the boundary line cannot be detected, a plurality of images representing the relevant object (100, 104, 106) are collected, a minimum lateral offset of the relevant object (100, 104, 106) relative to the motor vehicle is selected based on the collected plurality of images, and a virtual lane (102) is set based on the selected minimum lateral offset.

Images