Steering assist system

Abstract

To provide a steering support device which determines whether steering support to avoid an obstacle is executable or not when a compartment line does not exist at an opposite side to an existing position of the obstacle ahead of a vehicle on a driveway.SOLUTION: A steering support device 1 comprises: a recognition part S1 which recognizes existence of an obstacle 10 ahead of a vehicle 4 on a driveway 5 and recognizes whether the obstacle 10 exists at a left side of the driveway 5 or at a right side thereof; a first determination part S2 which determines whether a center line 7 or a driveway outside line 8 exists at an opposite side of existing position of the obstacle 10 on the driveway 5; second determination parts S6, S7 which determine, when existence of the obstacle 10 and the existing position are recognized by the recognition part S1 and when negative determination is given by the first determination part S2, whether steering to travel avoiding the obstacle 10 on the driveway 5 is possible or not; and first support parts S8, S5 which perform, when positive determination is given by the second determination parts S6, S7, steering support to travel avoiding the obstacle 10 on the driveway 5.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a steering assistance device that assists a driver of a vehicle in steering.

Background Art

[0002] For example, in Patent Document 1, when avoiding a front obstacle, it is described that by looking at the available width within the lane, it is determined whether to change lanes to an adjacent lane (opposite lane or overtaking lane) or to avoid within the traveling lane, and an avoidance operation is performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above Patent Document 1, since it is a technology premised on one - lane in one - way or two - lanes in one - way, when there are no dividing lines (center line, outside - lane line) on the opposite side of the position where an obstacle in front of the vehicle exists in the lane, it can be said that it cannot be the subject of whether to perform steering assistance for avoiding the obstacle.

[0005] In view of such circumstances, an object of the present invention is to provide a steering assistance device that can be the subject of whether to perform steering assistance for avoiding an obstacle even when there are no dividing lines (center line, outside - lane line) on the opposite side of the position where an obstacle in front of the vehicle exists in the lane.

Means for Solving the Problems

[0006] The present invention relates to a steering assistance device that assists a vehicle driver in steering, comprising: a recognition unit that recognizes whether or not there is an obstacle in front of the vehicle on the roadway and whether or not the location of the obstacle is to the left or to the right of the roadway; a first determination unit that determines whether or not there is a lane marking on the opposite side of the location of the obstacle on the roadway; a second determination unit that determines whether or not it is possible to steer the vehicle to avoid the obstacle on the roadway when the recognition unit recognizes the presence and location of the obstacle and the first determination unit determines that it is not possible; and a first assistance unit that provides steering assistance to steer the vehicle to avoid the obstacle on the roadway when the second determination unit determines that it is possible. When the recognition unit recognizes the presence and location of the obstacle and the first determination unit makes a positive determination, a third determination unit determines whether or not it is possible to drive in a manner that avoids the obstacle within the roadway; when the third determination unit makes a positive determination, a second support unit provides steering assistance for driving in a manner that avoids the obstacle within the roadway; when the third determination unit makes a negative determination, a fourth determination unit determines whether or not it is possible to steer in a manner that avoids the obstacle while deviating from the lane markings; and when the fourth determination unit makes a positive determination, a third support unit provides steering assistance for driving in a manner that avoids the obstacle while deviating from the lane markings. It is characterized by containing [something].

[0007] The aforementioned roadway refers to the lane on which vehicles travel, also known as a lane or roadway line. The aforementioned lane markings refer to the center line or the outer edge line of the roadway. Furthermore, if there are no lane markings on the roadway, the boundaries with the land or buildings exist at the left and right edges of the roadway, and these left and right boundaries allow for the distinction between the inside and outside of the roadway.

[0008] According to this configuration, if there is an obstacle in front of the vehicle on the roadway and there is no lane marking on the opposite side of the roadway from the location of the obstacle, and if steering is possible to avoid the obstacle within the roadway, then assistance for such steering will be provided.

[0009] Incidentally, in the steering support device described above, if the second determination unit makes a negative determination, the device can be configured to proceed to the recognition unit's processing without performing steering support.

[0010] With this configuration, if there is an obstacle in front of the vehicle on the roadway and there is no lane marking on the opposite side of the roadway from the location of the obstacle, and it is impossible to steer the vehicle to avoid the obstacle within the roadway, then the steering assistance will not be provided, and the driver will be responsible for performing the steering.

[0012] Also, the above According to the configuration, if there is an obstacle in front of the vehicle on the roadway and there is a lane marking on the opposite side of the roadway from the location of the obstacle, and if steering is possible to avoid the obstacle within the roadway, then assistance for such steering can be provided.

[0014] Also, the above According to the configuration, if there is an obstacle in front of the vehicle on the roadway and there is a lane marking on the opposite side of the roadway from the location of the obstacle, and if it is possible to steer the vehicle to avoid the obstacle while deviating from the lane marking, then assistance for such steering can be provided.

[0015] Incidentally, the first support unit can be configured to include a first generation unit (S8 in Figure 2) that generates an avoidance path for driving in a roadway to avoid the obstacle, and a first implementation unit (S5 in Figure 2) that provides steering assistance based on the avoidance path generated by the first generation unit.

[0016] Furthermore, the second support unit may be configured to include a second generation unit (S11 in Figure 2) that generates an avoidance path for driving while deviating from the lane markings to avoid the obstacle, and a second implementation unit (S5 in Figure 2) that provides steering assistance based on the avoidance path generated by the second generation unit.

[0017] Furthermore, the third support unit may be configured to include a third generation unit (S4 in Figure 2) that generates an avoidance path for driving in a way that avoids the obstacle within the roadway, and a third implementation unit (S5 in Figure 2) that provides steering assistance based on the path generated by the third generation unit. [Effects of the Invention]

[0018] According to the present invention, even in cases where there are no lane markings (center line, outer lane line) on the opposite side of the location of an obstacle in front of the vehicle on the roadway, it is possible to provide a steering assistance device that determines whether or not steering assistance can be provided to avoid the obstacle.

Brief Description of the Drawings

[0019] [Figure 1] It is a diagram showing the configuration of an embodiment of a steering assistance device according to the present invention. [Figure 2] It is a flowchart used to explain the operation of the steering assistance device. [Figure 3] It is a diagram for explaining an example of determination as to whether to perform steering assistance for avoiding an obstacle while deviating from the center line on a two-way single-lane road having lane dividing lines (center line and outside lane line). [Figure 4] It is a diagram for explaining an example of determination as to whether to perform steering assistance for avoiding an obstacle within a lane on a two-way single-lane road without a center line and outside lane lines. [Figure 5] It is a diagram for explaining another example of determination as to whether to perform steering assistance for avoiding an obstacle while deviating from the center line on a two-way single-lane road having a center line and outside lane lines.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the accompanying drawings.

[0021] An embodiment of the present invention is shown in FIGS. 1 to 5. The steering assistance device 1 shown in FIG. 1 assists the steering by the driver of the vehicle 4, and an input device 2 and an electric power steering device (EPS) 3 are connected via an interface not shown in the figure.

[0022] Although not shown in detail, the steering assistance device 1 is composed of a known electronic control unit (ECU), and based on the information input from the input device 2, controls the electric power steering device 3 to perform the necessary steering assistance for avoiding the obstacle 10 when the obstacle 10 exists in front of the vehicle 4 in the lane 5 based on a predetermined program.

[0023] Note that the obstacle 10 is, for example, a vehicle stopped on the left or right side of the road lane 5, a pedestrian walking on the left or right side of the road lane 5, or the like.

[0024] The ECU includes a central processing unit (CPU), a non-volatile memory device (Read Only Memory: ROM), a temporary memory device (Random Access Memory: RAM), and the like.

[0025] The ROM stores various control programs and maps that are referred to when executing these various control programs. The CPU executes arithmetic processing based on the various control programs and maps stored in the ROM. The RAM is a memory that temporarily stores the arithmetic results in the CPU and data input from each sensor.

[0026] The input device 2 is a device necessary for recognizing the presence or absence of the obstacle 10 and the presence position of the obstacle 10 in front of the vehicle 4 in the road lane 5. Although not shown, for example, it is a camera, a millimeter-wave radar, a GPS (Global Positioning System) device, an acceleration sensor, a vehicle speed sensor, or the like. Various information obtained by the input device 2 is input to the steering assistance device 1.

[0027] Note that the camera is an imaging device that captures an image (still image or moving image) in front of the vehicle 4, and is, for example, a video camera incorporating an image sensor (CCD: Charge-Coupled Device, CMOS: Complementary Metal-Oxide-Semiconductor) or the like. The obstacle 10 can be detected by performing analysis processing on the image captured by this camera. A known method can be adopted as a specific method for this image analysis processing.

[0028] Furthermore, the millimeter-wave radar emits millimeter waves (electromagnetic waves with wavelengths of 1 to 10 millimeters) toward an object and detects the distance to the object by receiving the reflected waves. The GPS device detects positioning information related to the vehicle's position (e.g., latitude, longitude, altitude). The acceleration sensor detects the acceleration of the vehicle 4 (longitudinal acceleration, lateral acceleration, vertical acceleration, etc.). The vehicle speed sensor detects the vehicle's speed.

[0029] The electric power steering system 3 steers the vehicle 4, and steering is controlled by the steering support device 1 in response to steering wheel operation information (not shown), and steering assistance is also controlled by the steering support device 1 depending on the situation.

[0030] Although not shown, this electric power steering system 3 includes a steering actuator that controls the steering angle of the vehicle's wheels 4 and a steering reaction actuator that controls the reaction force on the steering wheel.

[0031] Next, the operation of the steering assist device 1 will be explained with reference to the flowchart shown in Figure 2. The flowchart shown in Figure 2 starts when the ignition key (not shown) equipped on the vehicle 4 is turned ON.

[0032] First, in step S1, based on various information input from the input device 2 mounted on the vehicle 4, the system recognizes whether or not an obstacle 10 exists in front of the vehicle 4 on the roadway 5, and also recognizes whether the recognized obstacle 10 is located to the left or right of the roadway 5.

[0033] Here, the image captured by the camera of input device 2 is subjected to analysis processing, and the roadway 5, opposing lane 6, center line 7, outer lane line 8, oncoming vehicle 9, obstacle 10, boundary 11, preceding vehicle 12, etc. are recognized in the image.

[0034] In the following step S2, it is determined whether or not there are lane markings (center line 7, outer lane line 8) on the opposite side of the roadway 5 from the location of the obstacle 10. In step S2, if the obstacle 10 is located on the left side of the roadway 5, it is determined whether or not there is a center line 7, while if the obstacle 10 is located on the right side of the roadway 5, it is determined whether or not there is an outer lane line 8.

[0035] In step S2, if the result is positive, in step S3, it is determined whether or not the vehicle can be driven within the roadway 5 in a manner that avoids the obstacle 10. In other words, in step S3, it is determined whether or not the vehicle can be driven without deviating from the center line 7 or the outer line 8 of the roadway in a manner that avoids the obstacle 10.

[0036] On the other hand, if a negative result is obtained in step S2, the process proceeds to steps S6-S8. First, in step S6, it is confirmed whether there is space within the roadway 5 to avoid the obstacle 10, and then in step S7, it is determined whether steering is possible to avoid the obstacle 10 within the roadway 5.

[0037] In step S7, if a negative determination is made, the vehicle proceeds to step S1 without performing steering assistance. However, if a positive determination is made, in step S8, an avoidance route is created to avoid the obstacle 10 within the roadway 5.

[0038] Subsequently, in step S5, steering assistance is provided to drive the vehicle on the roadway 5 in a manner that avoids the obstacle 10 based on the avoidance path created in step S8.

[0039] Then, if a positive determination is made in step S3, in step S4, an avoidance route is created for driving in the roadway 5 to avoid the obstacle 10, and then in step S5, steering assistance is provided for driving in the roadway 5 to avoid the obstacle 10 based on the avoidance route created in step S4.

[0040] On the other hand, if a negative result is obtained in step S3, the process proceeds to steps S9-S11. First, in step S9, it is checked whether there is space outside the roadway 5 to avoid the obstacle 10. Then, in step S10, it is determined whether steering is possible to avoid the obstacle 10 while deviating from the lane markings (center line 7, outer lane line 8).

[0041] In step S10, if a negative determination is made, the system proceeds to step S1 without performing steering assistance. However, if a positive determination is made, in step S11, an avoidance route is created to avoid the obstacle 10 while deviating from the lane markings (center line 7, outer lane line 8). In this case, it is preferable to set the avoidance distance (amount of lane departure) to minimize the approach to the outer lane line 8 or boundary 11 of the oncoming lane 6. Furthermore, it is preferable to control the vehicle with a faster steering angular velocity than usual in order to quickly return to the roadway 5 from the oncoming lane 6.

[0042] Subsequently, in step S5, steering assistance is provided to drive in a manner that avoids the obstacle 10 while deviating from the lane markings (center line 7, outer lane line 8) based on the avoidance route created in step S11.

[0043] In the flowchart of Figure 2, step S1 corresponds to the recognition unit described in the claims, step S2 corresponds to the first determination unit described in the claims, step S3 corresponds to the third determination unit described in the claims, steps S4 and S5 correspond to the second support unit described in the claims, steps S6 and S7 correspond to the second determination unit described in the claims, steps S8 and S5 correspond to the first support unit described in the claims, steps S9 and S10 correspond to the fourth determination unit described in the claims, and steps S11 and S5 correspond to the third support unit described in the claims.

[0044] Next, with reference to Figures 3 to 5, we will explain an example of vehicle 4 avoiding obstacle 10.

[0045] Figure 3 illustrates an example of a decision on whether or not to provide steering assistance to avoid an obstacle 10 while deviating from the center line 7 on a one-lane road in each direction, where the roadway 5 has a center line 7 and a roadway edge line 8.

[0046] In the case of a one-lane road in each direction as shown in Figure 3, if an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5, steering assistance will be provided to avoid the obstacle 10 by deviating from the center line 7 if no oncoming vehicle 9 is traveling within the oncoming vehicle confirmation range X of the oncoming lane 6. However, if an oncoming vehicle 9 is traveling within the oncoming vehicle confirmation range X, the steering assistance will not be provided.

[0047] The oncoming vehicle detection range X is defined as a distance of 2L + V × t1 from the planned lane departure start time t1, where t0 is the time when lane departure is determined, V is the vehicle speed of vehicle 4, L is the lane departure distance, t1 is the planned lane departure start time (position), and t2 is the planned lane departure end time (position), where t2 = t1 + L / V.

[0048] Although not shown in the diagram, in a round-trip, one-lane roadway with a center line 7 but no left or right outer lane lines 8,8, if an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5, the process for determining whether or not to provide steering assistance to avoid the obstacle 10 while deviating from the center line 7 is the same as described above. In this way, on a round-trip, one-lane roadway with a center line 7 but no left or right outer lane lines 8,8, the distance from the center line 7 to the boundary 11 of the land or building on the left side in the direction of vehicle travel becomes the width of the roadway 5. Furthermore, since well-known techniques can be used for recognizing the boundary 11, a detailed explanation is omitted here.

[0049] Figure 4 illustrates an example of a decision on whether or not to implement steering assistance to avoid an obstacle 10 within the carriageway 5 on a one-lane road in both directions where there is no center line 7 and outer lane line 8 on the carriageway 5.

[0050] In the case of the one-lane road shown in Figure 4, the width of the roadway 5 is the distance from the boundary 11 between the roadway 5 and the land or building on the left side in the direction of vehicle travel to the boundary 11 between the roadway 5 and the land or building on the right side in the direction of vehicle travel.

[0051] First, it is determined whether the width W of the space to the side of the obstacle 10 on the roadway 5 is greater than the total width W1 + margin W2 of the vehicle 4. The width W of the space is the width from the right edge of the obstacle 10 to the right boundary 11 of the roadway 5, and the margin W2 can be set as appropriate through experiments or simulations.

[0052] If a negative result is obtained, the steering assistance will not be performed. However, if a positive result is obtained, it will be determined whether or not an oncoming vehicle 9 is traveling within the oncoming vehicle detection range X = 2L + V × t1.

[0053] If an oncoming vehicle 9 is traveling within the oncoming vehicle detection range X, the steering assistance will not be performed. However, if an oncoming vehicle 9 is not traveling within the oncoming vehicle detection range X, the steering assistance will be performed.

[0054] Figure 5 illustrates another example of the process for determining whether or not to implement steering assistance to avoid an obstacle 10 while deviating from the center line 7 on a one-lane road in each direction, where the roadway 5 has a center line 7 and a roadway edge line 8.

[0055] In the case of a one-lane road in each direction as shown in Figure 5, if an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5, and it is determined that the preceding vehicle 12 is avoiding the obstacle 10 while deviating from the center line 7, and the following conditions are met, steering assistance will be provided to avoid the obstacle 10 while deviating from the center line 7.

[0056] The aforementioned condition is that, when the speed of vehicle 4 is V and the distance from vehicle 4 to the preceding vehicle 12 is M, the interval time M / V is less than or equal to a predetermined judgment value. The judgment value is set appropriately through experiments or simulations, but can be, for example, 2 seconds.

[0057] The judgment criteria in Figure 5 fall within the same category as the criteria used in Figure 3 to determine that no oncoming vehicle 9 is approaching within the oncoming vehicle detection range X. Therefore, the judgment criteria in Figure 5 and Figure 3 can be selectively used when deciding whether or not to implement steering assistance.

[0058] As described above, according to embodiments to which the present invention is applied, when obstacles 10 such as vehicles or pedestrians are present on roadways 5 of various types, steering assistance to avoid obstacles 10 can be flexibly implemented or not implemented.

[0059] For example, on a one-lane road in both directions where there is no center line 7 and outer lane line 8 on the roadway 5, if there is an obstacle 10 in front of the vehicle 4, and it is possible to steer the vehicle within the roadway 5 to avoid the obstacle 10, the system will provide steering assistance. However, if steering is not possible, the system will not provide steering assistance and will leave the matter to the driver.

[0060] Furthermore, on a road with one lane in each direction, where the roadway 5 has a center line 7 and an outer lane line 8, if an obstacle 10 is present in front of the vehicle 4, and it is possible to steer the vehicle within the roadway 5 to avoid the obstacle 10, then it becomes possible to provide assistance for such steering.

[0061] Furthermore, in the case of a one-lane road in each direction with a center line 7 and an outer lane line 8 on the roadway 5, if an obstacle 10 is present in front of the vehicle 4, and it is possible to steer the vehicle to avoid the obstacle 10 while deviating from the center line 7 and the outer lane line 8, then assistance for such steering can be provided.

[0062] Thus, according to this embodiment, even when an obstacle 10 is present in front of the vehicle 4 on the roadway 5, and there is no center line 7 and roadway edge line 8 on the opposite side of the location of the obstacle 10 on the roadway 5, steering assistance to avoid the obstacle 10 can still be considered.

[0063] It should be noted that the present invention is not limited to the embodiments described above, and can be modified as appropriate within the scope of the claims and equivalents thereof.

[0064] (1) In the above embodiment, for example, although not shown, it is possible to omit steps S9 to S11 in Figure 2. In this case, if a negative determination is made in step S3, it is possible to proceed to step S1 without providing steering assistance.

[0065] (2) In the above embodiment, although not shown, it is also possible to connect, for example, a video display device (dedicated display, in-vehicle car navigation system) or an audio output device (dedicated speaker, in-vehicle music speaker) to the steering support device 1 to visually and audibly communicate to the driver that steering support is being provided. [Industrial applicability]

[0066] The present invention can be suitably used in a steering assistance device that provides steering assistance to the driver of a vehicle. [Explanation of symbols]

[0067] 1. Steering assist system 2 Input devices 3. Electric power steering system 4 vehicles 5 Roadway 6. Opposing lane 7 Chuo Line 8. Outer edge line of the roadway 9. Oncoming vehicles 10 Obstacles 11 Boundary 12. Leading vehicle

Claims

1. A steering assist device that assists the driver of a vehicle in steering, A recognition unit that recognizes whether or not there is an obstacle in front of the vehicle on the roadway, and recognizes whether the location of the obstacle is to the left or right of the roadway, A first determination unit that determines whether or not there is a lane marking on the opposite side of the location of the obstacle in the aforementioned roadway, When the recognition unit recognizes the presence and location of the obstacle and the first determination unit determines that it is not possible, the second determination unit determines whether or not it is possible to steer the vehicle to avoid the obstacle within the roadway. When the second determination unit makes a positive determination, the first support unit provides steering assistance to drive the vehicle in a manner that avoids the obstacle within the roadway, When the recognition unit recognizes the presence and location of the obstacle and the first determination unit makes a positive determination, a third determination unit determines whether or not the vehicle can be driven in a manner that avoids the obstacle within the roadway, When the third determination unit makes a positive determination, the second support unit provides steering assistance to drive the vehicle in a manner that avoids the obstacle within the roadway, If the third determination unit determines that the result is negative, a fourth determination unit determines whether or not it is possible to steer the vehicle to avoid the obstacle while deviating from the lane markings, A steering assistance device characterized by including a third support unit that, when the fourth determination unit makes a positive determination, provides steering assistance to drive in a manner that avoids the obstacle while deviating from the lane markings.

2. In the steering support device according to claim 1, A steering assistance device characterized in that, if the second determination unit determines that the steering assistance is not performed, the device proceeds to the processing of the recognition unit.

Images