Headlight control device

Abstract

To suppress a sense of confusion or trouble to an occupant when an amount of change of a steering angle of an own vehicle is a specified value or more.SOLUTION: A controller 18 of a headlight control device 10 controls an irradiation range of auxiliary headlights 26L, 26R of an own vehicle based on a steering angle of the own vehicle. The controller 18 makes, when an amount of change of the steering angle of the own vehicle is more than a specified value, an irradiation light amount of the auxiliary headlights 26L, 26R be smaller, the auxiliary headlights 26L, 26R be turned off, or the irradiation range of the auxiliary head lights 26L, 26R be enlarged relative to a case that the amount of change of the steering angle of the own vehicle is the specified value or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a headlamp control device.

Background Art

[0002] Patent Document 1 describes calculating a reach point of the host vehicle after a predetermined time based on the vehicle speed and steering angle of the host vehicle, and controlling the irradiation direction of the headlamp so that the calculated reach point is within the irradiation range of the headlamp of the host vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In technologies that control the irradiation range from a headlamp according to the steering angle of the host vehicle, including the technology described in Patent Document 1, a control delay in the irradiation range occurs with respect to a change in the line of sight of the occupant in a situation where the amount of change in the steering angle of the host vehicle becomes a predetermined value or more, such as when the host vehicle approaches a curve. In this case, due to the control delay in the irradiation range, the movement of the irradiation range is delayed with respect to the change in the line of sight of the occupant, which may cause confusion and annoyance to the occupant. Note that the above control delay in the irradiation range also occurs not only at the entrance of the curve described above, but also at the exit of the curve, when steering is reversed in the middle of an S-curve, etc.

[0005] The present disclosure has been made in consideration of the above facts, and an object thereof is to obtain a headlamp control device that can suppress giving confusion and annoyance to an occupant when the amount of change in the steering angle of the host vehicle becomes a predetermined value or more.

Means for Solving the Problems

[0006] The headlight control device according to the first embodiment controls the illumination range from the headlights of the vehicle based on the steering angle of the vehicle, and the amount of change in the steering angle of the vehicle is greater than a predetermined value. between The system includes a control unit that reduces the amount of light emitted from the headlights, turns off the headlights, or expands the illumination range from the headlights, compared to when the amount of change in the steering angle is less than or equal to the predetermined value.

[0007] In the first embodiment, the control unit controls the illumination range from the vehicle's headlights based on the vehicle's steering angle. The control unit also controls the range of illumination from the vehicle's headlights when the change in the vehicle's steering angle is greater than a predetermined value. between When the amount of change in steering angle is below a predetermined value, the amount of light emitted from the headlights is reduced, the headlights are turned off, or the illumination range from the headlights is expanded. This makes the control delay of the illumination range from the headlights that occurs when the amount of change in the vehicle's steering angle exceeds a predetermined value less noticeable to the occupants, thereby suppressing confusion and inconvenience to the occupants.

[0008] In the second aspect, in the first aspect, the control unit, when the amount of change in the steering angle is less than or equal to the predetermined value, adjusts the illumination range from the headlights so that it is curved on the road surface according to the steering angle. Long shape The system is controlled to produce a specific irradiation pattern.

[0009] In the second embodiment, when the amount of change in the steering angle of the vehicle is less than or equal to a predetermined value, the illumination range from the headlights is curved on the road surface in accordance with the steering angle of the vehicle. Long shape The system controls the illumination pattern to match the desired pattern. This allows the vehicle to accurately illuminate the road it is about to travel on, using an illumination pattern that curves according to the vehicle's steering angle, when the change in the vehicle's steering angle is below a predetermined value.

[0010] A third aspect is the second aspect, wherein the irradiation pattern is a long pattern with a width corresponding to the width of the vehicle.

[0011] In the third embodiment, the illumination pattern on the road surface is a long, elongated pattern with a width corresponding to the width of the vehicle, so that if there is a narrow section on the route the vehicle is about to travel, the occupants can be made aware of whether or not the vehicle can pass through the narrow section. [Effects of the Invention]

[0012] This disclosure has the effect of preventing confusion and inconvenience to the occupants when the amount of change in the steering angle of the vehicle exceeds a predetermined value. [Brief explanation of the drawing]

[0013] [Figure 1] This is a block diagram showing a schematic configuration of a vehicle headlight system according to an embodiment. [Figure 2] This is a schematic diagram showing an example of the configuration of an auxiliary headlight. [Figure 3] This is a schematic diagram showing an example of an irradiation pattern. [Figure 4] This is a flowchart showing the details of the auxiliary headlight control process. [Figure 5] This is a schematic diagram showing an example of the changes in illumination light intensity and illumination pattern due to auxiliary headlight control processing. [Figure 6] This is a schematic diagram illustrating that the movement of the irradiation range is delayed due to a delay in controlling the irradiation range. [Modes for carrying out the invention]

[0014] Hereinafter, an example of an embodiment of the present disclosure will be described in detail with reference to the drawings. The vehicle headlight system 10 shown in Figure 1 is mounted on a vehicle (the vehicle itself) and includes a light switch 12, a steering angle sensor 14, a headlight control ECU (Electronic Control Unit) 16, a pair of left and right headlights 24L, 24R and a pair of left and right auxiliary headlights 26L, 26R.

[0015] Note that the headlight control ECU 16 in the vehicle headlight system 10 is an example of the headlight control device according to the present disclosure, and the auxiliary headlights 26L and 26R are examples of the headlights in the present disclosure. Further, an example of the host vehicle on which the vehicle headlight system 10 is mounted is an emergency vehicle such as an ambulance, a fire truck, or a police vehicle.

[0016] The light switch 12 is connected to the headlight control ECU 16 via a communication line such as a CAN (Controller Area Network) bus. The light switch 12 is provided with a plurality of contacts including a first contact for instructing the lighting of the vehicle headlights 24L and 24R and a second contact for instructing the extinguishing of the vehicle headlights 24L and 24R. When the light switch 12 is operated by a vehicle occupant, any one of the plurality of contacts is turned on, and switch contact information indicating which contact is turned on is output to the headlight control ECU 16.

[0017] The steering angle sensor 14 detects the steering angle of the host vehicle. The steering angle sensor 14 is connected to the headlight control ECU 16 via a communication line (for example, a CAN bus or the like), and outputs the steering angle of the host vehicle to the headlight control ECU 16.

[0018] The headlights 24L and 24R are headlights with a constant light distribution pattern that illuminate a certain range in front of the vehicle. The light sources of the headlights 24L and 24R may be any of an LED (Light Emitting Diode), an HID (High Intensity Discharge), or a halogen bulb.

[0019] On the one hand, the auxiliary headlights 26L and 26R are auxiliary lights that emit light toward the road surface and can change the irradiation pattern of the light on the road surface. The auxiliary headlights 26L and 26R can adopt a configuration including, for example, an LED array 28 in which a plurality of LED chips 27 are arranged in a matrix, as shown marked as the micro-LED method in Fig. 2(A), and a lens 30 arranged on the light emission side of the LED array 28. In this configuration (micro-LED method), the light emitted from each individual LED chip 27 will be arranged in a matrix on the road surface, and by controlling the lighting and extinguishing of each individual LED chip 27, the irradiation pattern on the road surface can be changed into an arbitrary pattern.

[0020] In this embodiment, a plurality of irradiation patterns on the road surface by the auxiliary headlights 26L and 26R are defined as shown in Fig. 3. That is, among the plurality of irradiation patterns, there is included a long (rectangular) pattern (refer to the "irradiation pattern during straight travel" in Fig. 3) with a width corresponding to the vehicle width of the host vehicle, corresponding to the state where the host vehicle is traveling straight with a steering angle = 0. Also, in a state where the steering wheel is rotated counterclockwise and the host vehicle is making a left turn, a plurality of long patterns with different degrees of curvature corresponding to different steering angles and with a width corresponding to the vehicle width of the host vehicle (refer to the "irradiation pattern during left turn" in Fig. 3) are prepared. Further, in a state where the steering wheel is rotated clockwise and the host vehicle is making a right turn, a plurality of long patterns with different degrees of curvature corresponding to different steering angles and with a width corresponding to the vehicle width of the host vehicle (refer to the "irradiation pattern during right turn" in Fig. 3) are prepared.

[0021] The headlight control ECU 16 includes a CPU (Central Processing Unit), memory such as ROM (Read Only Memory) and RAM (Random Access Memory), a non-volatile storage unit 20 such as an HDD (Hard Disk Drive) and SSD (Solid State Drive), and a communication I / F (Interface). The storage unit 20 stores a program (not shown) for causing the CPU of the headlight control ECU 16 to function as a control unit 18, and illumination pattern control information 22. The illumination pattern control information 22 is information that defines the on / off control pattern of each LED chip 27 for each illumination pattern so that the illumination pattern on the road surface by the auxiliary headlights 26L and 26R becomes one of the above-mentioned multiple illumination patterns.

[0022] The control unit 18 illuminates the headlights 24L and 24R based on the switch contact information input from the light switch 12, if the first contact of the light switch 12 is ON. The headlight control ECU 16 also turns off the headlights 24L and 24R if the second contact of the light switch 12 is ON. The control unit 18 may also be configured to illuminate the headlights 24L and 24R when the illuminance around the vehicle falls below a threshold.

[0023] Furthermore, the control unit 18 also illuminates the auxiliary headlights 26L and 26R while the headlights 24L and 24R are illuminated. When illuminating the auxiliary headlights 26L and 26R, the control unit 18 obtains the steering angle of the vehicle from the steering angle sensor 14 and controls the illumination range from the auxiliary headlights 26L and 26R to match the illumination pattern corresponding to the acquired steering angle of the vehicle. However, if the change in the steering angle of the vehicle is greater than a predetermined value, the control unit 18 reduces the amount of light emitted from the auxiliary headlights 26L and 26R compared to when the change in the steering angle of the vehicle is less than or equal to a predetermined value.

[0024] Next, as an example of the operation of this embodiment, the auxiliary headlight control process executed by the control unit 18 (CPU of the headlight control ECU 16) while the vehicle's ignition switch is ON will be explained with reference to Figure 4.

[0025] In step 50 of the auxiliary headlight control process, the control unit 18 determines whether the conditions for lighting the auxiliary headlights 26L and 26R are met. The determination in step 50 can be, for example, determined to be met if the headlights 24L and 24R are lit. Alternatively, for example, it can be determined that the conditions for lighting the auxiliary headlights 26L and 26R are met if the illuminance around the vehicle falls below a threshold. Furthermore, for example, it is also possible to determine that the conditions for lighting the auxiliary headlights 26L and 26R are met if a switch for instructing the turning on or off of the auxiliary headlight 26 is provided, and a predetermined contact for instructing the lighting of the auxiliary headlight 26 is turned on in the switch.

[0026] If the determination in step 50 is negative, the process proceeds to step 52. In step 52, the control unit 18 turns off the auxiliary headlights 26L and 26R. After the process in step 52 is completed, the process returns to step 50, and steps 50 and 52 are repeated until the determination in step 50 is affirmed. If the conditions for the auxiliary headlights 26L and 26R to be lit are met, the determination in step 50 is affirmed and the process proceeds to step 54.

[0027] In step 54, the control unit 18 obtains the steering angle of the vehicle from the steering angle sensor 14. In step 56, the control unit 18 selects an illumination pattern corresponding to the direction and magnitude of the vehicle's steering angle obtained in step 54 as the illumination range (illumination pattern on the road surface) from the auxiliary headlights 26L and 26R. The control unit 18 then reads out the illumination pattern control information 22 corresponding to the selected illumination pattern.

[0028] In step 58, the control unit 18 obtains the steering angle of the vehicle again from the steering angle sensor 14 and calculates the change in the steering angle of the vehicle from the steering angles of the vehicle obtained in steps 54 and 58, respectively. In step 60, the control unit 18 determines whether the absolute value of the change in the steering angle calculated in step 58 is greater than a predetermined value. If the determination in step 60 is negative, the process proceeds to step 62.

[0029] In step 62, the control unit 18 determines whether the state in which the amount of change in steering angle is less than or equal to a predetermined value has continued for a predetermined time or longer. If the determination in step 62 is affirmative, the system proceeds to step 64. In step 64, the control unit 18 sets the amount of light emitted from the auxiliary headlights 26L and 26R to the normal light intensity. On the other hand, if the determination in step 60 is affirmative, or if the determination in step 62 is negative, the system proceeds to step 66. In step 66, the control unit 18 sets the amount of light emitted from the auxiliary headlights 26L and 26R to a value that is reduced from the normal light intensity.

[0030] After completing step 64 or step 66, the process proceeds to step 68. In step 68, the control unit 18 illuminates the auxiliary headlights 26L and 26R with the illumination pattern selected in step 56 and the light intensity set in step 64 or step 66, based on the illumination pattern control information 22 read in step 56. After completing step 68, the process returns to step 50, and the processes from step 50 onward are repeated.

[0031] As shown in Figure 5(A), the auxiliary headlight control process described above ensures that when the vehicle is traveling in a straight line, the auxiliary headlights 26L and 26R are controlled to emit light at their normal intensity. Furthermore, the illumination range of the auxiliary headlights 26L and 26R is controlled according to the vehicle's steering angle (=0) so that the illumination pattern on the road surface is elongated (rectangular) with a width corresponding to the vehicle's width.

[0032] Furthermore, when the vehicle approaches a left curve, as shown in Figure 5(B), the illumination range of the auxiliary headlights 26L and 26R is controlled so that the illumination pattern on the road surface is a long, curved pattern that is wide to the left according to the steering angle of the vehicle, with a width corresponding to the width of the vehicle. However, at this time, the amount of change in the steering angle of the vehicle exceeds a predetermined value, so as shown in Figures 5(B) and 6, a control delay in the illumination range (illumination pattern) occurs in response to the change in the occupant's line of sight. In contrast, when the amount of change in the steering angle of the vehicle exceeds a predetermined value, the illumination amount of the auxiliary headlights 26L and 26R is reduced to the normal amount, so the aforementioned control delay becomes less noticeable to the occupant, and confusion and inconvenience to the occupant are suppressed.

[0033] Furthermore, when the vehicle is turning a curve with an approximately constant steering angle, as shown in Figure 5(C), the control delay of the illumination range (illumination pattern) in response to changes in the occupant's line of sight is eliminated. Also, as the amount of change in the vehicle's steering angle falls below a predetermined value, the illumination amount of the auxiliary headlights 26L and 26R returns to normal, allowing the road the vehicle is about to travel on to be accurately illuminated.

[0034] As described above, in this embodiment, the control unit 18 of the vehicle headlight system 10 controls the illumination range from the auxiliary headlights 26L and 26R of the vehicle based on the steering angle of the vehicle. Furthermore, when the amount of change in the steering angle of the vehicle is greater than a predetermined value, the control unit 18 reduces the amount of light emitted from the auxiliary headlights 26L and 26R compared to when the amount of change in the steering angle of the vehicle is less than or equal to the predetermined value. As a result, the control delay in the illumination range from the auxiliary headlights 26L and 26R that occurs when the amount of change in the steering angle of the vehicle exceeds a predetermined value becomes less noticeable to the occupants, thereby suppressing confusion and inconvenience to the occupants.

[0035] Furthermore, in this embodiment, when the amount of change in the steering angle of the vehicle is less than or equal to a predetermined value, the control unit 18 controls the illumination range from the auxiliary headlights 26L and 26R so that the illumination pattern on the road surface is curved according to the steering angle of the vehicle. As a result, when the amount of change in the steering angle of the vehicle is less than or equal to a predetermined value, the road that the vehicle is about to travel on can be accurately illuminated by the illumination pattern curved according to the steering angle of the vehicle.

[0036] Furthermore, in this embodiment, the illumination pattern on the road surface is a long, elongated pattern with a width corresponding to the vehicle's width. This allows the occupants to recognize whether or not the vehicle can pass through a narrow section on the route it is about to travel. Specifically, in the case of an emergency vehicle equipped with the vehicle headlight system 10, as an example of the above-mentioned narrow section, where the vehicle is making an emergency run through a gap between other vehicles parked on the road, the occupants can recognize whether or not the vehicle can pass through the gap between the other vehicles. This can support the smooth operation of the emergency vehicle.

[0037] In the above embodiment, an emergency vehicle was described as an example of a vehicle equipped with the vehicle headlight system 10. However, this disclosure is not limited to this, and the headlight control device according to this disclosure may be installed in vehicles other than emergency vehicles.

[0038] Furthermore, in the above embodiment, a mode was described in which the amount of light emitted from the auxiliary headlights 26L and 26R is reduced when the amount of change in the steering angle of the vehicle is greater than a predetermined value, compared to when the amount of change in the steering angle of the vehicle is less than or equal to a predetermined value. However, this disclosure is not limited thereto. For example, when the amount of change in the steering angle of the vehicle is greater than a predetermined value, the auxiliary headlights 26L and 26R may be turned off, or the illumination range from the auxiliary headlights 26L and 26R may be expanded compared to when the amount of change in the steering angle of the vehicle is within a predetermined value. In these cases as well, the control delay of the illumination range from the auxiliary headlights 26L and 26R is less likely to be perceived by the occupants, thereby suppressing confusion and inconvenience to the occupants. When the illumination range is expanded, the illumination range may be, for example, the range equivalent to the low beam of the headlights 24L and 24R.

[0039] Furthermore, in the above embodiment, the micro-LED system shown in Figure 2(A) was described as a configuration for auxiliary headlights 26L and 26R that can change the illumination pattern on the road surface, but this disclosure is not limited to the micro-LED system.

[0040] For example, in the DMD (Digital Mirror Device) system shown in Figure 2(B), the DMD 34 and lens 30 are arranged in order on the light-emitting side of the LED light source 32. The DMD 34 has multiple micromirrors 36 whose angles can be changed arranged in a matrix, and each micromirror 36 is controlled to either a first angle that reflects the incident light into the lens 30, or a second angle that reflects the incident light out of the lens 30. When the DMD system is adopted for the auxiliary headlights 26L and 26R, with each micromirror 36 of the DMD 34 controlled to the first angle, the light reflected by each micromirror 36 is arranged in a matrix on the road surface. Therefore, by controlling the angle of each micromirror 36 to the first or second angle, it is possible to change the illumination pattern on the road surface to any desired pattern.

[0041] Furthermore, in the laser scanning method shown in Figure 2(C), for example, a MEMS (Micro Electro Mechanical System) mirror 40, a phosphor 42, and a lens 30 are arranged in order on the light-emitting side of the blue laser light source 38. The angle of the MEMS mirror 40 is controlled so that the laser light incident on the mirror is scanned in two dimensions. The phosphor 42 performs wavelength conversion of the incident scanning laser light. When the laser scanning method is adopted for the auxiliary headlights 26L and 26R, the laser light reflected by the MEMS mirror 40 and passing sequentially through the phosphor 42 and lens 30 scans the road surface in two dimensions. Therefore, by controlling the on / off switching of the blue laser light source 38 at the timing when the laser light scans each position on the road surface, it is possible to change the illumination pattern on the road surface to any desired pattern.

[0042] Furthermore, in the liquid crystal system shown in Figure 2(D), for example, a liquid crystal panel 48, which has a liquid crystal layer 44 sandwiched between a pair of polarizing plates 46, and a lens 30 are arranged in order on the light-emitting side of an LED array 28 in which multiple LED chips 27 are arranged in a matrix. When the liquid crystal system is adopted for the auxiliary headlights 26L and 26R, the light transmitted through each liquid crystal cell of the liquid crystal panel 48 is arranged in a matrix on the road surface, and by controlling the light transmittance of each liquid crystal cell of the liquid crystal panel 48, it is possible to change the illumination pattern on the road surface to any desired pattern. [Explanation of Symbols]

[0043] 10. Vehicle headlight systems 14. Steering angle sensor 16. Headlight control ECU (Headlight control device) 18 Control Unit 26L, 26R auxiliary headlight

Claims

1. A headlight control device that controls the illumination range from the headlights of the vehicle based on the steering angle of the vehicle, and includes a control unit that, while the amount of change in the steering angle of the vehicle is greater than a predetermined value, reduces the amount of light emitted from the headlights, turns off the headlights, or expands the illumination range from the headlights compared to when the amount of change in the steering angle is less than or equal to the predetermined value.

2. The headlight control device according to claim 1, wherein the control unit controls the illumination range from the headlight to become a curved, elongated illumination pattern on the road surface according to the steering angle when the amount of change in the steering angle is less than or equal to the predetermined value.

3. The headlight control device according to claim 2, wherein the illumination pattern is a long, elongated pattern with a width corresponding to the width of the vehicle.

Images