Steering support device

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 assist device that assists a driver of a vehicle in steering. [Background technology]

[0002] For example, Patent Document 1 describes how, when avoiding an obstacle ahead, the vehicle looks at the available space in the roadway and decides whether to change lanes to an adjacent lane (the oncoming lane or the passing lane) or to avoid the obstacle within the driving lane, and then performs the evasive action. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-089990 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology in Patent Document 1 is based on the premise that there is one lane or two lanes in each direction. Therefore, if there is no dividing line (center line, outer road line) on the opposite side of the roadway from the location of an obstacle ahead of the vehicle, it cannot be said that steering assistance to avoid the obstacle can be implemented.

[0005] In consideration of these circumstances, the present invention aims to provide a steering assist device that determines whether or not to implement steering assist to avoid an obstacle even when there is no dividing line (center line, outer roadway line) on the opposite side of the obstacle's location in front of the vehicle on the roadway. [Means for solving the problem]

[0006] The present invention is a steering assistance device that assists steering by a driver of a vehicle, and is characterized by including: a recognition unit that recognizes the presence or absence of an obstacle ahead of the vehicle on a roadway, and recognizes whether the obstacle is located on the left or right side of the roadway; a first judgment unit that determines whether there is a dividing line on the roadway on the opposite side of the location of the obstacle; a second judgment unit that, when the recognition unit recognizes the presence and location of the obstacle and the first judgment unit makes a negative judgment, determines whether steering is possible to travel within the roadway so as to avoid the obstacle; and a first assistance unit that, when the second judgment unit makes a positive judgment, performs steering assistance to travel within the roadway so as to avoid the obstacle.

[0007] The roadway is the lane on which vehicles travel, and is also called a lane or lane. The dividing lines are the center line and the outer lines of the roadway. Furthermore, if the roadway does not have dividing lines, the left and right ends of the roadway have boundaries with the land or buildings, and the inside and outside of the roadway can be recognized by the left and right boundaries.

[0008] According to this configuration, when an obstacle is present ahead of the vehicle on a roadway and there is no dividing line on the roadway opposite the location of the obstacle, if steering is possible to travel within the roadway in a way that avoids the obstacle, assistance with the steering is provided.

[0009] Incidentally, in the above steering assist device, when a negative determination is made by the second determination unit, the steering assist may not be performed and the process may proceed to the processing by the recognition unit.

[0010] According to this configuration, if there is an obstacle ahead of the vehicle on the roadway and there is no dividing line on the roadway opposite the location of the obstacle, if it is impossible to steer the vehicle within the roadway to avoid the obstacle, it is possible to leave the steering assistance to the driver without providing such assistance.

[0011] In addition, the steering assistance device may further include a third judgment unit that judges whether or not it is possible to travel within the roadway in a manner that avoids the obstacle when the recognition unit recognizes the existence and location of the obstacle and the first judgment unit makes a positive judgment, and a third assistance unit that performs steering assistance for traveling within the roadway in a manner that avoids the obstacle when the third judgment unit makes a positive judgment.

[0012] According to this configuration, when an obstacle is present ahead of the vehicle on a roadway and there is a dividing line on the roadway on the opposite side of the location of the obstacle, if steering is possible to travel within the roadway in a way that avoids the obstacle, assistance with the steering can be provided.

[0013] In addition, the above steering assistance device may be configured to further include a fourth judgment unit that judges whether steering is possible to travel so as to avoid the obstacle while deviating from the lane marking when a negative judgment is made by the third judgment unit, and a second assistance unit that performs steering assistance to travel so as to avoid the obstacle while deviating from the lane marking when a positive judgment is made by the fourth judgment unit.

[0014] According to this configuration, when an obstacle is present ahead of the vehicle on the roadway and there is a dividing line on the roadway on the opposite side of the location of the obstacle, if steering is possible to travel so as to deviate from the dividing line and avoid the obstacle, assistance with the steering can be provided.

[0015] The first assistance unit may be configured to include a first generation unit (S8 in FIG. 2) that generates an avoidance path for traveling so as to avoid the obstacle within the roadway, and a first implementation unit (S5 in FIG. 2) that performs steering assistance based on the avoidance path generated by the first generation unit.

[0016] In addition, the second assistance unit may be configured to include a second generation unit (S11 in FIG. 2) that generates an avoidance path for traveling so as to avoid the obstacle while deviating from the dividing line, and a second implementation unit (S5 in FIG. 2) that performs steering assistance based on the avoidance path generated by the second generation unit.

[0017] In addition, the third assistance unit may be configured to include a third generation unit (S4 in FIG. 2) that generates an avoidance path for traveling within the roadway to avoid the obstacle, and a third implementation unit (S5 in FIG. 2) that performs steering assistance based on the path generated by the third generation unit. Effect of the Invention

[0018] According to the present invention, a steering assist device can be provided that determines whether or not to implement steering assist to avoid an obstacle even when there is no dividing line (center line, outer roadway line) on the opposite side of the location of an obstacle in front of the vehicle on the roadway. [Brief description of the drawings]

[0019] [Figure 1] 1 is a diagram showing a configuration of an embodiment of a steering assist device according to the present invention; [Diagram 2] 4 is a flowchart used to explain the operation of the steering assist device. [Diagram 3] This figure is a diagram to explain an example of a determination as to whether or not to implement steering assistance to avoid an obstacle while deviating from the center line on a two-way, one-lane road with dividing lines (center line and outer side lines) on the roadway. [Figure 4] FIG. 1 is a diagram for explaining an example of a determination as to whether or not to perform steering assistance to avoid an obstacle on a roadway with one lane in both directions, where the roadway does not have a center line or an outer lane. [Diagram 5] FIG. 13 is a diagram for explaining another example of a determination as to whether or not to perform steering assistance to avoid an obstacle while deviating from the center line on a two-way, one-lane road with a center line and an outer edge line. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 Figures 1 to 5. The steering assist device 1 shown in Figure 1 assists the driver of a vehicle 4 in steering, and an input device 2 and an electric power steering device (EPS) 3 are connected via an interface (not shown).

[0022] The steering assist device 1, although not shown in detail, consists of a known electronic control unit (ECU), and based on information input from the input device 2, controls the electric power steering device 3 to provide the necessary steering assistance to avoid an obstacle 10 when the obstacle 10 is present ahead of the vehicle 4 on the roadway 5, based on a predetermined program.

[0023] The obstacle 10 may be, for example, a vehicle stopped on the left or right side of the roadway 5, or a pedestrian walking on the left or right side of the roadway 5.

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

[0025] The ROM stores various control programs and maps to be referenced when executing the various control programs. The CPU executes calculations based on the various control programs and maps stored in the ROM. The RAM is a memory that temporarily stores the results of calculations by the CPU, data input from each sensor, and the like.

[0026] The input device 2 is a device required for recognizing the presence or absence of an obstacle 10 ahead of the vehicle 4 on the roadway 5 and the position of the obstacle 10, and although not shown, may be, for example, a camera, a millimeter wave radar, a GPS (Global Positioning System) device, an acceleration sensor, a vehicle speed sensor, etc. Various information obtained by the input device 2 is input to the steering assist device 1.

[0027] The camera is an imaging device that captures images (still images or video images) in front of the vehicle 4, and is, for example, a video camera with a built-in imaging element (CCD: Charge-Coupled Device, CMOS: Complementary Metal-Oxide-Semiconductor). Obstacle 10 can be detected by performing an analysis process on the image captured by this camera. A known method can be used as a specific method for this image analysis process.

[0028] The millimeter wave radar transmits millimeter waves (electromagnetic waves with a wavelength 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 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 traveling speed (vehicle speed) of the vehicle 4.

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

[0030] Although not shown, the electric power steering device 3 includes a steering actuator that controls the steering angle of the wheels of the vehicle 4, and a steering reaction force actuator that controls the reaction force to the steering wheel.

[0031] Next, the operation of the steering assist device 1 will be described with reference to the flowchart shown in Fig. 2. The flowchart shown in Fig. 2 starts when an ignition key (not shown) equipped in 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, it is recognized whether or not an obstacle 10 is present ahead of the vehicle 4 on the roadway 5, and it is also recognized whether the recognized obstacle 10 is present on the left or right side of the roadway 5.

[0033] Here, an analysis process is performed on the image captured by the camera of the input device 2, and the roadway 5, oncoming lane 6, center line 7, outer roadway line 8, oncoming vehicles 9, obstacles 10, boundaries 11, leading vehicles 12, etc. are recognized in the image.

[0034] In the next step S2, it is determined whether or not there are dividing lines (center line 7, outer roadway line 8) on the opposite side of the roadway 5 from the position where the obstacle 10 is present. In this step S2, if the obstacle 10 is present on the left side of the roadway 5, it is determined whether or not there is a center line 7, whereas if the obstacle 10 is present on the right side of the roadway 5, it is determined whether or not there is an outer roadway line 8.

[0035] If the determination in step S2 is affirmative, then in step S3 it is determined whether or not the vehicle can travel so as to avoid the obstacle 10 within the roadway 5. In other words, in step S3 it is determined whether or not the vehicle can travel so as to avoid the obstacle 10 without deviating from the center line 7 or the outer roadway line 8.

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

[0037] If the result of this step S7 is negative, the process proceeds to step S1 without implementing steering assistance, whereas if the result of this step S7 is positive, the process proceeds to step S8 in which an avoidance route is created for driving so as to avoid the obstacle 10 on the roadway 5.

[0038] Thereafter, in step S5, steering assistance is carried out to travel so as to avoid the obstacle 10 on the roadway 5 based on the avoidance route created in step S8.

[0039] If a positive judgment is made in step S3, an avoidance route is created in step S4 for driving so as to avoid the obstacle 10 on the roadway 5, and then, in step S5, steering assistance is implemented for driving so as to avoid the obstacle 10 on the roadway 5 based on the avoidance route created in step S4.

[0040] On the other hand, if the determination in step S3 is negative, the process proceeds to steps S9-S11. First, in step S9, it is confirmed whether there is a space outside the roadway 5 for avoiding the obstacle 10, and then in step S10, it is determined whether steering is possible to avoid the obstacle 10 while deviating from the dividing line (center line 7, outer roadway line 8).

[0041] If the result of the determination in step S10 is negative, the process proceeds to step S1 without implementing steering assistance, whereas if the result of the determination is positive, in step S11, an avoidance route is created for traveling so as to avoid the obstacle 10 while deviating from the dividing line (center line 7, outer roadway line 8). At this time, it is preferable to set the avoidance distance (lane deviation amount) so as to minimize approach to the outer roadway line 8 or boundary 11 of the oncoming lane 6. Also, in order to quickly return to the roadway 5 from the oncoming lane 6, it is preferable to perform control at a steering angle speed faster than normal.

[0042] Thereafter, in step S5, steering assistance is performed to travel so as to avoid the obstacle 10 while deviating from the lane markings (center line 7, outer roadway line 8) based on the avoidance route created in step S11.

[0043] In the flowchart of FIG. 2, step S1 corresponds to the recognition unit described in the claims, step S2 corresponds to the first judgment unit described in the claims, step S3 corresponds to the third judgment 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 judgment 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 judgment unit described in the claims, and steps S11 and S5 correspond to the third support unit described in the claims.

[0044] Next, an example of the traveling of the vehicle 4 avoiding the obstacle 10 will be described with reference to Figs.

[0045] FIG. 3 is a diagram for explaining an example of a determination as to 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 an outer side line 8.

[0046] In the case where an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5 on a two-way one-lane road shown in FIG. 3, if an oncoming vehicle 9 is not traveling within the oncoming vehicle confirmation range X of the oncoming lane 6, steering assistance is provided to avoid the obstacle 10 while deviating from the center line 7, whereas if an oncoming vehicle 9 is traveling within the oncoming vehicle confirmation range X, the steering assistance is not provided.

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

[0048] Although not shown, in a two-way one-lane roadway with a center line 7 but no left and right outer roadway lines 8, 8, when an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5, the process of determining whether or not to perform steering assistance to avoid the obstacle 10 while deviating from the center line 7 is the same as that described above. In this way, in a two-way one-lane road with a center line 7 but no left and right outer roadway lines 8, 8, the distance from the center line 7 to the boundary 11 with the land or building to the left of the vehicle's traveling direction is the width of the roadway 5. Also, since a well-known technology can be used to recognize the boundary 11, a detailed explanation will be omitted here.

[0049] FIG. 4 is a diagram for explaining an example of a determination as to whether or not to perform steering assistance to avoid an obstacle 10 on a road 5 having one lane in both directions, where the road 5 does not have a center line 7 or an outer side line 8.

[0050] In addition, in the case of the two-way single 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 of the vehicle's direction of travel to the boundary 11 between the roadway 5 and the land or building on the right side of the vehicle's direction of travel.

[0051] First, it is determined whether or not the width W of the free space on the side of the obstacle 10 on the roadway 5 is larger than the total width W1 of the vehicle 4 plus the margin width W2. The width W of the free space is the width from the right end of the obstacle 10 to the right boundary 11 of the roadway 5, and the margin width W2 can be appropriately set by experiments, simulations, etc.

[0052] If the determination is negative, the steering assistance is not implemented, but if the determination is positive, it is determined whether or not an oncoming vehicle 9 is traveling within the oncoming vehicle confirmation range X=2L+V×t1.

[0053] When an oncoming vehicle 9 is traveling within the oncoming vehicle confirmation range X, the steering assistance is not performed, but when an oncoming vehicle 9 is not traveling within the oncoming vehicle confirmation range X, the steering assistance is performed.

[0054] FIG. 5 is a diagram for explaining another example of a determination process as to whether or not to perform 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 an outer side line 8.

[0055] When an obstacle 10 such as a vehicle is stopped on the left side of the roadway 5 on a two-way one-lane road as shown in FIG. 5, if it is determined that the leading vehicle 12 is avoiding the obstacle 10 while deviating from the center line 7 and the following conditions are satisfied, steering assistance is provided to avoid the obstacle 10 while deviating from the center line 7.

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

[0057] It can be said that the judgment conditions in Fig. 5 are in the same category as the conditions for judging that the oncoming vehicle 9 is not traveling in the oncoming vehicle confirmation range X in Fig. 3. Therefore, the judgment conditions in Fig. 5 and the judgment conditions in Fig. 3 can be selectively used when judging whether or not to perform steering assistance.

[0058] As described above, according to the embodiment of the present invention, when an obstacle 10 such as a vehicle or a pedestrian is present on a roadway 5 of various shapes, steering assistance for avoiding the obstacle 10 can be flexibly performed or not performed.

[0059] For example, when an obstacle 10 is present ahead of the vehicle 4 on a two-way, one-lane road where the roadway 5 does not have a center line 7 or outer roadway line 8, if steering to drive within the roadway 5 so as to avoid the obstacle 10 is possible, then the steering assistance is provided, but if such steering is not possible, the steering assistance is not provided and the task can be left to the driver.

[0060] In addition, when an obstacle 10 is present ahead of the vehicle 4 on a one-lane road in each direction, such as a roadway 5 with a center line 7 and an outer roadway line 8, if steering is possible to travel within the roadway 5 so as to avoid the obstacle 10, assistance with said steering can be provided.

[0061] Furthermore, when an obstacle 10 is present ahead of the vehicle 4 on a one-lane road in each direction, such as a roadway 5 having a center line 7 and an outer lane 8, if steering is possible to travel so as to avoid the obstacle 10 while deviating from the center line 7 and the outer lane 8, assistance with such steering can be provided.

[0062] Thus, according to this embodiment, even if there is an obstacle 10 in front of the vehicle 4 on the roadway 5 and there is no center line 7 or outer roadway line 8 on the opposite side of the location of the obstacle 10 on the roadway 5, the obstacle 10 can be subject to the possibility of implementing steering assistance to avoid the obstacle 10.

[0063] The present invention is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the claims and a range equivalent to the claims.

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

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

[0066] The present invention can be suitably used in a steering assist device that performs steering assistance for a driver of a vehicle. [Explanation of symbols]

[0067] 1 Steering assist device 2 Input Devices 3. Electric power steering device 4. Vehicles 5 Roadway 6 Oncoming traffic 7. Chuo Line 8 Outside line of roadway 9 Oncoming vehicles 10 Obstacles 11 Boundary 12 Leading vehicle

Claims

1. A steering assist device that assists a driver of a vehicle in steering, a recognition unit that recognizes whether an obstacle is present ahead of the vehicle on a roadway and whether the obstacle is located to the left or right of the roadway; a first determination unit that determines whether or not a dividing line is present on the roadway on an opposite side to the position where the obstacle is present; a second determination unit that, when the recognition unit recognizes the presence and location of the obstacle and the first determination unit makes a negative determination, determines whether or not steering is possible to travel on the roadway so as to avoid the obstacle; A steering assist device characterized by including a first assistance unit that performs steering assistance to drive in a manner that avoids the obstacle on the roadway when a positive judgment is made by the second judgment unit.

2. The steering assist device according to claim 1, A steering assist device characterized in that, when a negative judgment is made by the second judgment unit, the steering assist is not performed and the processing is transitioned to the recognition unit.

3. The steering assist device according to claim 1 or 2, a third determination unit that, when the recognition unit recognizes the presence and location of the obstacle and the first determination unit makes a positive determination, determines whether or not the vehicle can travel on the roadway in a manner that avoids the obstacle; A steering assist device further comprising: a second assistance unit that performs steering assistance to drive in a manner that avoids the obstacle on the roadway when a positive judgment is made by the third judgment unit.

4. The steering assist device according to claim 3, a fourth determination unit that determines whether steering is possible to travel so as to avoid the obstacle while deviating from the lane marking when a negative determination is made by the third determination unit; and A steering assist device further comprising: a third assistance unit that, when a positive judgment is made by the fourth judgment unit, performs steering assistance to drive so as to avoid the obstacle while deviating from the lane marking.

Images