Vehicle lamp control method and device

Abstract

To prevent traffic participants around an own vehicle from being confused when the own vehicle changes lanes.SOLUTION: When an own vehicle changes lanes, a light pattern is projected from lamps of the own vehicle in a direction extending from the own vehicle to the lane side as a change destination, in which three partial projection regions having a predetermined shape are aligned in the direction extending from the own vehicle to the change destination. In addition, at the timing when the lane change has progressed, the number of partial projection regions having the predetermined shape included in the light pattern is reduced, thereby reducing the length of the light pattern to be shorter than that at the timing when the lane change has started.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a vehicle lamp control method and a vehicle lamp control device.

Background Art

[0002] Patent Document 1 describes a technique of projecting a path display image indicating the path of the host vehicle onto the road surface around the host vehicle when the host vehicle turns right or left (see FIGS. 4 and 5 of Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the host vehicle changes lanes, if a light pattern is projected from the host vehicle toward the lane to be changed, the light pattern may be projected beyond the lane to be changed, which may cause confusion to traffic participants existing around the host vehicle.

[0005] The present disclosure has been made in consideration of the above facts, and an object thereof is to obtain a vehicle lamp control method and a vehicle lamp control device that can suppress causing confusion to traffic participants existing around the host vehicle when the host vehicle changes lanes.

Means for Solving the Problems

[0006] A vehicle lamp control method according to a first aspect projects a light pattern from a lamp of the host vehicle in a direction extending from the host vehicle toward the side of the lane to be changed when the host vehicle changes lanes, and shortens the length of the light pattern at a timing when the lane change has progressed compared to a timing at the start of the lane change.

[0007] In the first aspect, at the timing when the lane change of the host vehicle has progressed, the length of the light pattern projected in the direction extending from the host vehicle toward the lane of the lane change destination is made shorter than the timing of the start of the lane change of the host vehicle. Thereby, since it is suppressed that the light pattern is projected beyond the lane of the lane change destination, it is possible to suppress giving confusion to traffic participants existing around the host vehicle.

[0008] The second aspect is, in the first aspect, wherein the light pattern is a pattern in which two or more partial projection regions of a predetermined shape are arranged in the direction extending from the host vehicle toward the lane of the lane change destination.

[0009] In the second aspect, since the light pattern is a pattern in which two or more partial projection regions of a predetermined shape are arranged in the direction extending from the host vehicle toward the lane of the lane change destination, traffic participants existing around the host vehicle can easily recognize the light pattern.

[0010] The third aspect is, in the second aspect, wherein the length of the light pattern is shortened by reducing the number of the partial projection regions of the predetermined shape included in the light pattern.

[0011] In the third aspect, the length of the light pattern is shortened by reducing the number of the partial projection regions of a predetermined shape included in the light pattern. Thereby, traffic participants existing around the host vehicle can easily recognize that the length of the light pattern has become shorter.

[0012] The fourth aspect is, in the first aspect, wherein the length of the light pattern is shortened by reducing the size of the entire light pattern.

[0013] In the fourth aspect, the length of the light pattern is shortened by reducing the size of the entire light pattern. Thereby, traffic participants existing around the host vehicle can easily recognize that the length of the light pattern has become shorter.

[0014] The vehicle lamp control device according to the fifth aspect projects a light pattern in a direction extending from the vehicle lamp of the host vehicle toward the lane to which the host vehicle is changing lanes when the host vehicle changes lanes, and includes a control unit that shortens the length of the light pattern at the timing when the lane change progresses compared to the timing of the start of the lane change.

[0015] In the fifth aspect, similar to the first aspect, when the host vehicle changes lanes, it is possible to suppress causing confusion to traffic participants existing around the host vehicle.

Advantages of the Invention

[0016] The present disclosure has an effect that it is possible to suppress causing confusion to traffic participants existing around the host vehicle when the host vehicle changes lanes.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0018] Hereinafter, an example of an embodiment of the present disclosure will be described in detail with reference to the drawings. As shown in FIG. 1, a vehicle lamp device 10 according to this embodiment includes a sensor group 12, a sensor control device 24, a driving operation information recording device 26, a navigation system 27, a lane change steering assistance function unit 28, a lamp lighting control device 30, and a lamp unit 32. Hereinafter, the vehicle on which the vehicle lamp device 10 is mounted will be referred to as the "own vehicle".

[0019] The sensor group 12 includes sensors such as a camera 14, an angular velocity sensor 16, a vehicle speed sensor 18, a steering wheel angle sensor 20, and a turn signal lever switch 22. The camera 14 images the surroundings of the own vehicle and outputs the imaging result as image information. The angular velocity sensor 16 detects the angular velocity of the own vehicle and outputs angular velocity information. The vehicle speed sensor 18 detects the vehicle speed of the own vehicle and outputs vehicle speed information. The steering wheel angle sensor 20 detects the steering angle of the own vehicle and outputs steering angle information. When the turn signal lever of the own vehicle is turned on to the left or right by the occupant of the own vehicle during a left or right turn or a route change to the left or right, the turn signal lever switch 22 switches the contact position and outputs contact position information representing the contact position.

[0020] The sensor control device 24 supplies power to each sensor of the sensor group 12, receives the information output from each sensor, and performs processing for monitoring the state of the own vehicle. The driving operation information recording device 26 records operations of the turn signal lever by the occupant of the own vehicle as driving operation information. The navigation system 27 performs processing for displaying the position of the own vehicle on a map or determining and guiding a route to a destination based on the position information of the own vehicle measured by a GNSS (Global Navigation Satellite System) sensor and map information.

[0021] When the lane change steering assist function unit 28 satisfies the first lane change condition and determines that the surrounding situation detected by the sensor group 12 is a situation where lane change is possible, it cooperates with the sensor control device 24, the driving operation information recording device 26, and the navigation system 27 to perform automatic steering when the host vehicle changes lanes. The first lane change condition includes, for example, when the turn signal lever is turned on to the left or right by the occupant of the host vehicle while the host vehicle is traveling under cruise control.

[0022] The lamp lighting control device 30 incorporates a CPU (Central Processing Unit), memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and a non-volatile storage unit such as an HDD (Hard Disk Drive) and an SSD (Solid State Drive). The storage unit stores a predetermined program for causing the CPU of the lamp lighting control device 30 to function as a control unit. The control unit projects an optical pattern from the lamp unit 32 of the host vehicle in a direction extending from the host vehicle toward the lane of the lane change destination, and controls to make the length of the optical pattern shorter at the timing when the lane change progresses than at the timing of the start of the lane change. Note that the lamp lighting control device 30 is an example of the vehicle lamp control device according to the present disclosure.

[0023] On the one hand, the lamp unit 32 is an auxiliary light that emits light toward the road surface around the host vehicle and can change the light pattern irradiated on the road surface. In the present embodiment, the lamp units 32 are provided at the left and right front ends and side portions of the vehicle, respectively. Each lamp unit 32 may adopt a configuration including an LED array 34 in which a plurality of LED chips 36 are arranged in a matrix, as indicated by the micro LED method in FIG. 2(A) for example, and a lens 38 arranged on the light emission side of the LED array 34. In this configuration (micro LED method), the light emitted from each LED chip 36 is arranged in a matrix on the road surface, and by controlling the turning on and off of each LED chip 36, the light pattern irradiated on the road surface can be changed to an arbitrary pattern.

[0024] Next, as an operation of the present embodiment, the light pattern projection control process executed by the CPU of the lamp lighting control device 30 while the ignition switch of the host vehicle is on will be described with reference to FIG. 3. In step 70 of the light pattern projection control process, the lamp lighting control device 30 stops the projection of the light pattern from the lamp unit 32 onto the road surface around the host vehicle.

[0025] In step 72, the lamp lighting control device 30 determines whether or not the light pattern projection function for projecting the light pattern from the lamp unit 32 onto the road surface around the host vehicle is set to "effective". The light pattern projection function is set to "effective" or "invalid" by operating a switch (not shown) by the occupant of the host vehicle, for example. If the determination in step 72 is negative, the process returns to step 70, and if the determination in step 72 is positive, the process proceeds to step 74.

[0026] In step 74, the lamp lighting control device 30 acquires the contact position information output from the turn signal lever switch 22 via the sensor control device 24, and determines whether the turn signal lever is turned on to the left or right based on the acquired information. If the determination in step 74 is negative, the process returns to step 70, and if the determination in step 74 is positive, the process proceeds to step 76.

[0027] In step 76, the lamp lighting control device 30 projects a light pattern onto the road surface around the host vehicle from the lamp unit 32 corresponding to the direction in which the turn signal lever is turned on, by full lighting. As an example, FIG. 4(A) shows an example in which the turn signal lever is turned on to the right, and a light pattern is projected onto the surrounding road surface by full lighting from the lamp units 32 at the right front end and the right side of the corresponding host vehicle. The light pattern shown in FIG. 4(A) is a pattern in which three partial projection regions in an inverted V shape convex in the direction away from the host vehicle are arranged in the direction extending from the host vehicle to the side of the lane to which the lane change is to be made, and the width of the partial projection region is increased as it moves away from the host vehicle. Thus, by projecting a light pattern onto the road surface around the host vehicle, traffic participants existing around the host vehicle can be made to recognize that the host vehicle is about to turn right or left or change lanes to the left or right. In the present embodiment, when the host vehicle makes a right or left turn or the like, the light pattern is maintained in the fully lit state.

[0028] Note that the number of partial projection regions constituting the light pattern may be other than three. Also, in the above step 76, when projecting the light pattern from the lamp unit 32 onto the road surface, it is not limited to maintaining the light pattern in the fully lit state. For example, the partial projection regions to be lit in the light pattern may be switched, and the light pattern may be changed like an animation.

[0029] In the next step 78, the lamp lighting control device 30 determines whether it can communicate with each functional unit of the sensor control device 24, the driving operation information recording device 26, the navigation system 27, and the lane change steering assistance function unit 28. When an abnormality such as a communication failure occurs, the determination in step 78 is negated and the process returns to step 70, but in normal times, the determination in step 78 is affirmed and the process proceeds to step 80.

[0030] In step 80, the lamp lighting control device 30 determines whether any of the functional units of the sensor control device 24, the driving operation information recording device 26, the navigation system 27, and the lane change steering assist function unit 28 is transmitting a signal indicating that automatic steering is being performed during a lane change of the host vehicle. If the determination in step 80 is negative, the process proceeds to step 82. If the determination in step 80 is positive, the process proceeds to step 84.

[0031] In step 82, the lamp lighting control device 30 determines whether the information from the sensor control device 24 satisfies the second lane change condition, that is, whether the lane change of the host vehicle is being performed manually. If the determination in step 82 is negative, the process returns to step 70. If the determination in step 82 is positive, the process proceeds to step 84. An example of the second lane change condition is a case where it is detected from the image captured by the camera 14 that the host vehicle is straddling a lane, the steering angle of the steering of the host vehicle is less than a predetermined angle threshold, and the angular velocity of the host vehicle is less than a predetermined angular velocity threshold. As the angle threshold, for example, ±15° can be applied, and as the angular velocity threshold, for example, 0.3G can be applied.

[0032] Note that the determination of whether the lane change of the host vehicle is being performed manually is not limited to the above. For example, the driving situation of the host vehicle that can be detected from the image captured by the camera 14 may be compared with the map information of the navigation system 27 to determine whether the lane change of the host vehicle is being performed manually. Also, the point where the driver has performed a lane change in the past may be learned from an image captured by the camera 14 or the like, and when the current position of the host vehicle is the point where the driver has performed a lane change in the past, it may be determined whether the lane change of the host vehicle will be performed.

[0033] In step 84, the lamp lighting control device 30 determines whether to perform control of the light pattern associated with the lane change. If the determination in step 84 is negative, the process returns to step 70. If the determination in step 84 is positive, the process proceeds to step 86.

[0034] In step 86, the lamp lighting control device 30 determines, based on, for example, an image captured by the camera 14, whether or not the projection range of the light pattern emitted from the lamp unit 32 on the road surface extends beyond the lane to which the lane change is to be made. At the timing immediately after the start of the lane change, as shown in FIGS. 4(A) and 5(A), the projection range of the light pattern emitted from the lamp unit 32 on the road surface is within the lane to which the lane change is to be made. Therefore, the determination in step 86 is negative and the process returns to step 70.

[0035] On the other hand, at the timing when a certain amount of time has elapsed since the start of the lane change, as indicated by the dashed lines in FIGS. 4(B) and 4(C), the projection range of the light pattern emitted from the lamp unit 32 on the road surface extends beyond the lane to which the lane change is to be made. In this case, the determination in step 86 is affirmative and the process proceeds to step 88.

[0036] In step 88, the lamp lighting control device 30 detects the amount of protrusion of the projection range of the light pattern from the lane to which the lane change is to be made, and executes first control (extinguishing control) for extinguishing a part of the light pattern or second control (shrinking and deforming control) for shrinking and deforming the light pattern according to the detected amount of protrusion. In the next step 90, the lamp lighting control device 30 determines whether or not the lane change is continuing. If the determination in step 90 is negative, the process returns to step 70, and if the determination in step 90 is affirmative, the process returns to step 86.

[0037] When changing lanes to the right lane, the above-described steps 86 to 90 are repeated. An example of the control result when the first control (extinguishing control) is performed during this period is shown in FIGS. 4(B) and 4(C). At the timing shown in FIG. 4(B), the host vehicle straddles the lane, and among the lamp units 32 provided at the right front end and the right side of the host vehicle, the projection range of the light pattern emitted from the lamp unit 32 on the right side of the host vehicle protrudes from the lane immediately adjacent to the right of the lane change destination. Therefore, in step 88, as shown by the broken line in FIG. 4(B), for the lamp unit 32 on the right side of the host vehicle, among the light patterns emitted from the lamp unit 32, a partial projection area (the one partial projection area with the largest distance from the host vehicle) where the projection position protrudes from the lane immediately adjacent to the right is extinguished.

[0038] Also, at the timing shown in FIG. 4(C), the lane change has progressed more than the timing shown in FIG. 4(B), and the host vehicle is moving into the lane immediately adjacent to the right of the lane change destination. And at this timing, the projection ranges of the light patterns emitted from the lamp units 32 at the right front end and the right side of the host vehicle each protrude from the lane immediately adjacent to the right of the lane change destination. Therefore, in step 88, as shown by the broken line in FIG. 4(C), for the lamp units 32 at the right front end and the right side of the host vehicle, among the light patterns emitted from these lamp units 32, a partial projection area where the projection position protrudes from the lane immediately adjacent to the right is extinguished. That is, among the light patterns emitted from the lamp unit 32 on the right side of the host vehicle, a partial projection area (two partial projection areas in the order of the largest distance from the host vehicle) where the projection position protrudes from the lane immediately adjacent to the right is extinguished. Also, among the light patterns emitted from the lamp unit 32 at the right front end of the host vehicle, a partial projection area (the one partial projection area with the largest distance from the host vehicle) where the projection position protrudes from the lane immediately adjacent to the right is extinguished. Thereby, it is suppressed that traffic participants existing around the host vehicle are confused.

[0039] Also, when changing lanes to the right lane, steps 86 to 90 described above are repeated. An example of the control result when the second control (reduction transformation control) is performed during this period is shown in FIGS. 5(B) and 5(C). At the timing shown in FIG. 5(B), the host vehicle straddles the lane, and the projection range of the light pattern emitted from the lamp unit 32 on the right side of the host vehicle will protrude from the lane immediately adjacent to the right of the lane change destination (see also FIG. 4(B)). Therefore, in step 88, as shown by the dashed line in FIG. 4(B), the lamp unit 32 on the right side of the host vehicle is adjusted so that the projection range of the light pattern emitted from the lamp unit 32 does not protrude from the adjacent lane (so that none of the three partial projection areas constituting the light pattern protrude from the adjacent lane), and the light pattern is reduced and deformed.

[0040] Also, at the timing shown in FIG. 5(C), the lane change has progressed more than the timing shown in FIG. 5(B), and the host vehicle is moving into the lane immediately adjacent to the right of the lane change destination. And at this timing, if the second control is not performed, the projection ranges of the light patterns emitted from the right front end and the right side lamp unit 32 of the host vehicle will each protrude from the lane immediately adjacent to the right of the lane change destination (see also FIG. 4(C)). Therefore, in step 88, as shown in FIG. 5(C), the right front end and the right side lamp unit 32 of the host vehicle are adjusted so that the projection ranges of the light patterns emitted from these lamp units 32 do not protrude from the adjacent lane, and the light pattern is reduced and deformed at a reduction rate larger than that at the timing shown in FIG. 5(B). Also in this case, it is possible to suppress causing confusion to traffic participants existing around the host vehicle. Note that the reduction rate when reducing and deforming the light pattern may be the same or different in the direction in which the light pattern extends (the arrangement direction of the partial projection areas) and the direction intersecting therewith (the width direction of the partial projection areas).

[0041] When the lane change to the lane of the lane change destination is completed through the above control, the determination in step 90 is affirmed and the process returns to step 70, and the projection of the light pattern ends.

[0042] As described above, in this embodiment, when the host vehicle changes lanes, a light pattern is projected from the lamp unit 32 of the host vehicle in a direction extending from the host vehicle toward the lane to which the lane change is to be made. At the timing when the lane change progresses, the length of the light pattern is made shorter than the timing of the start of the lane change. Thereby, it is possible to suppress the light pattern from being projected beyond the lane to which the lane change is to be made, and to suppress confusing the traffic participants existing around the host vehicle.

[0043] Further, in this embodiment, the light pattern is a pattern in which two or more partial projection regions of a predetermined shape are arranged in a direction extending from the host vehicle toward the lane to which the lane change is to be made. Thereby, it becomes easier for the traffic participants existing around the host vehicle to recognize the light pattern.

[0044] Further, in the first control of this embodiment, the length of the light pattern is shortened by reducing the number of partial projection regions of a predetermined shape included in the light pattern. Thereby, it becomes easier for the traffic participants existing around the host vehicle to recognize that the length of the light pattern has become shorter.

[0045] Further, in the second control of this embodiment, the length of the light pattern is shortened by reducing the size of the entire light pattern. Thereby, it becomes easier for the traffic participants existing around the host vehicle to recognize that the length of the light pattern has become shorter.

[0046] Note that, in the above embodiment, the mode in which the lamp units 32 are provided at the left and right front ends and side portions of the host vehicle has been described, but the number and installation positions of the lamp units 32 are not limited to this. For example, the lamp units 32 may be provided only at the left and right front ends of the host vehicle, or may be provided only at the left and right side portions of the host vehicle.

[0047] In the above-described embodiment, the aspect in which the light pattern is a pattern in which two or more partial projection regions of a predetermined shape are arranged in a direction extending from the host vehicle to the side of the lane to be changed has been described. However, the present disclosure is not limited to this. In particular, in the aspect of performing the second control (reduction control), the light pattern may be a pattern composed of a single projection region (for example, an arrow-shaped region).

[0048] In the above-described embodiment, as the configuration of the lamp unit 32 capable of changing the light pattern irradiated on the road surface, the micro-LED method shown in FIG. 2(A) has been described. However, the present disclosure is not limited to the micro-LED method.

[0049] For example, in the DMD (Digital Mirror Device) method shown in FIG. 2(B), the DMD 42 and the lens 38 are sequentially arranged on the light emission side of the LED light source 40. The DMD 42 has a plurality of micro-mirrors 44 with changeable angles arranged in a matrix. Each micro-mirror 44 is controlled to a first angle that reflects incident light into the lens 38 or a second angle that reflects incident light outside the lens 38. When the DMD method is adopted as the lamp unit 32, with each micro-mirror 44 of the DMD 42 controlled to the first angle, the light reflected by each micro-mirror 44 will be arranged in a matrix on the road surface. Therefore, by controlling the angle of each micro-mirror 44 to the first angle or the second angle, the light pattern irradiated on the road surface can be changed to an arbitrary pattern.

[0050] Also, for example, in the laser scanning method shown in Fig. 2(C), an MEMS (Micro Electro Mechanical System) mirror 48, a phosphor 50, and a lens 38 are arranged in order on the light emission side of the blue laser light source 46. The angle of the MEMS mirror 48 is controlled so as to two-dimensionally scan the laser light incident on the mirror. The phosphor 50 performs wavelength conversion of the incident scanned laser light. When the laser scanning method is adopted as the lamp unit 32, the laser light reflected by the MEMS mirror 48 and passing through the phosphor 50 and the lens 38 in order scans the road surface two-dimensionally. Therefore, by controlling the turning on and off of the blue laser light source 46 at the timing when the laser light scans each position on the road surface, the light pattern irradiated on the road surface can be changed to an arbitrary pattern.

[0051] Also, for example, in the liquid crystal method shown in Fig. 2(D), a liquid crystal panel 56 configured by sandwiching the front and back surfaces of a liquid crystal layer �2 with a pair of polarizing plates 54 and a lens 38 are arranged in order on the light emission side of an LED array 34 in which a plurality of LED chips 36 are arranged in a matrix. When the liquid crystal method is adopted as the lamp unit 32, the light transmitted through the individual liquid crystal cells of the liquid crystal panel 56 is arranged in a matrix on the road surface, and by controlling the light transmittance of the individual liquid crystal cells of the liquid crystal panel 56, the light pattern irradiated on the road surface can be changed to an arbitrary pattern.

Description of Reference Numerals

[0052] 10 Vehicle lamp device 12 Sensor group 24 Sensor control device 26 Driving operation information recording device 27 Navigation system 28 Lane change steering assistance function unit 30 Lamp lighting control device 32 Lamp unit

Claims

**Claim 1** A vehicle lamp control method, which projects a light pattern from a lamp of the host vehicle in a direction extending from the host vehicle toward the lane to be changed when the host vehicle changes lanes, and shortens the length of the light pattern at the timing when the lane change has progressed compared to the timing of the start of the lane change. **Claim 2** The vehicle lamp control method according to claim 1, wherein the light pattern is a pattern in which two or more partial projection regions of a predetermined shape are arranged in a direction extending from the host vehicle toward the lane to be changed. **Claim 3** The vehicle lamp control method according to claim 2, wherein the length of the light pattern is shortened by reducing the number of the partial projection regions of the predetermined shape included in the light pattern. **Claim 4** The vehicle lamp control method according to claim 1, wherein the length of the light pattern is shortened by reducing the size of the entire light pattern. **Claim 5** A vehicle lamp control device including a control unit that projects a light pattern from a lamp of the host vehicle in a direction extending from the host vehicle toward the lane to be changed when the host vehicle changes lanes, and shortens the length of the light pattern at the timing when the lane change has progressed compared to the timing of the start of the lane change.

Images