Vehicle lighting control system

Abstract

By adjusting the beam axis of the vehicle's headlights based on glare information from the preceding vehicle, glare for the driver of the preceding vehicle is effectively suppressed. [Solution] A vehicle lighting control system for controlling the headlights of a vehicle, comprising: a glare information acquisition unit that acquires glare information regarding glare detected by a preceding vehicle traveling in front of the vehicle via vehicle-to-vehicle communication; a glare determination unit that determines whether or not the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle based on the glare information acquired from the preceding vehicle; and a lighting control unit that, when the glare determination unit determines that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle, executes glare suppression control to lower the optical axis of the headlights.

Description

Technical Field

[0001] The present invention relates to a vehicle lighting control system.

Background Art

[0002] Conventionally, as a technical document regarding a vehicle lighting control system, Japanese Patent Application Laid-Open No. 2014-120113 is known. In this publication, when a preceding vehicle traveling in front of the host vehicle detects glare caused by the headlight of an oncoming vehicle or the like, the host vehicle receives glare information from the preceding vehicle, and an anti-glare process for suppressing the occurrence of glare to the driver of the host vehicle is executed.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, not only glare caused by the headlight of an oncoming vehicle but also glare may be caused to the driver of a preceding vehicle through the mirror of the preceding vehicle by the headlight of a following vehicle. In such a case, it is desirable to control the headlight of the following vehicle to suppress glare.

Means for Solving the Problems

[0005] One aspect of the present invention is a vehicle lighting control system for controlling the headlights of a vehicle, comprising: a glare information acquisition unit that acquires glare information regarding glare detected by a preceding vehicle traveling in front of the vehicle via vehicle-to-vehicle communication; a glare determination unit that determines whether or not the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle based on the glare information acquired from the preceding vehicle; and a lighting control unit that, when the glare determination unit determines that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle, executes glare suppression control to lower the optical axis of the headlights. [Effects of the Invention]

[0006] According to one aspect of the present invention, a vehicle lighting control system can effectively suppress glare directed at the driver of a preceding vehicle by adjusting the optical axis of the vehicle's headlights based on glare information from a preceding vehicle. [Brief explanation of the drawing]

[0007] [Figure 1] This is a block diagram showing a vehicle lighting control system according to one embodiment. [Figure 2] This flowchart shows an example of the glare information generation process in the ECU of a preceding vehicle. [Figure 3] This flowchart shows an example of the glare suppression control initiation process in the vehicle's ECU. [Figure 4] This flowchart shows an example of the glare suppression control termination process in the vehicle's ECU. [Modes for carrying out the invention]

[0008] Embodiments of the present invention will be described below with reference to the drawings.

[0009] Figure 1 is a block diagram showing a vehicle lighting control system 100 according to one embodiment. The vehicle lighting control system 100 shown in Figure 1 is a system that controls the headlights of the vehicle M, and has the function of suppressing glare to the driver of the preceding vehicle N by adjusting the optical axis of the headlights of the vehicle M based on glare information from the preceding vehicle N.

[0010] The preceding vehicle N is another vehicle traveling in front of the vehicle M. The vehicle M may perform follow control such as ACC (Adaptive Cruise Control) for the preceding vehicle N. The vehicle lighting control system 100 may be configured as a system for multiple vehicles, including the preceding vehicle N, or it may be configured as a system for the vehicle M alone.

[0011] The vehicle lighting control system 100 includes an external sensor 1, a communication unit 2, an auto-leveling mechanism 3, and an ECU 10 (Electronic Control Unit). The external sensor 1 is a detection device that detects the conditions around the vehicle M. The external sensor 1 includes at least one of a camera and a radar sensor.

[0012] The camera is an imaging device that captures images of the external conditions of the vehicle M. The camera is installed, for example, behind the windshield of the vehicle M and captures images of the area in front of the vehicle M. The camera transmits the captured images of the external conditions of the vehicle M to the ECU 10. The radar sensor is a detection device that uses radio waves (e.g., millimeter waves) or light to detect objects around the vehicle M. Radar sensors include, for example, millimeter-wave radar or lidar [LiDAR: Light Detection and Ranging]. The radar sensor transmits information about the detected objects to the ECU 10.

[0013] The communication unit 2 is the component that performs vehicle-to-vehicle communication between the vehicle M and the preceding vehicle N. The communication unit 2 is mounted on the vehicle M and has the function of receiving glare information transmitted from the preceding vehicle N. Specifically, the communication unit 2 uses vehicle-to-vehicle communication technology to send and receive data with the communication unit 6 of the preceding vehicle N. This allows it to acquire glare information detected by the preceding vehicle N. The communication unit 2 then transmits the received glare information to the ECU 10.

[0014] The auto-leveling mechanism 3 is a mechanism for automatically adjusting the optical axis of the headlights of the vehicle M. The auto-leveling mechanism 3 operates based on control signals from the ECU 10. The auto-leveling mechanism 3 includes, for example, an actuator unit connected to the headlight unit and a group of sensors for detecting changes in the vehicle's attitude. The actuator unit consists of an electric motor, a reduction gear, and a linkage (connecting mechanism) for adjusting the angle of the headlights. The electric motor is driven based on control signals from the ECU 10. The rotational motion of the motor is converted into appropriate rotational speed and torque via a reduction gear such as a worm gear or spur gear. This gear mechanism reduces the high-speed rotation of the motor, enabling precise control. The reduced rotational motion is transmitted to the linkage, which finely adjusts the tilt angle of the headlight unit in the vertical direction. The linkage consists of, for example, a ball joint or a link arm, and is a mechanism for smoothly operating the headlight unit. The auto-leveling mechanism 3 is not limited to the above configuration and can employ various well-known configurations.

[0015] The ECU10 is an electronic control unit having a CPU (Central Processing Unit) and a memory unit. The memory unit consists of, for example, ROM (Read Only Memory), RAM (Random Access Memory), and EEPROM (Electrically Erasable Programmable Read-Only Memory). The ECU10 implements various functions by, for example, executing programs stored in the memory unit with the CPU. The ECU10 may be composed of multiple electronic units.

[0016] Next, the functional configuration of the ECU 10 will be described. As shown in Figure 1, the ECU 10 has a glare information acquisition unit 11 and a glare determination unit 12.

[0017] The glare information acquisition unit 11 acquires glare information transmitted from the preceding vehicle N. Specifically, the glare information acquisition unit 11 receives glare information transmitted from the communication unit 6 of the preceding vehicle N via vehicle-to-vehicle communication through the communication unit 2. The glare information includes the amount of glare detected by the glare sensor 5 of the preceding vehicle N and information on the operation of the automatic dimming mirror. Note that the operation information of the automatic dimming mirror is not mandatory. The glare information acquisition unit 11 transmits the received glare information to the glare determination unit 12 in the ECU 10, where it is used as data for glare determination.

[0018] The glare determination unit 12 determines, based on the glare information transmitted from the glare information acquisition unit 11, whether or not glare is being generated for the driver of the preceding vehicle N due to the light from the headlights of the vehicle M. Specifically, the glare determination unit 12 analyzes the received glare information and determines whether the amount of glare exceeds a standard value. It also takes into account the operation information of the automatic dimming mirror of the preceding vehicle N and the distance information between the vehicle M and the preceding vehicle N to make a comprehensive judgment on the glare occurrence situation.

[0019] The glare determination unit 12 determines that glare is being generated for the driver of the preceding vehicle N due to the light of the headlight of the host vehicle M when, for example, the automatic anti-glare mirror of the preceding vehicle N is operating and the distance between the host vehicle M and the preceding vehicle N is less than a certain distance. The certain distance may be a value that is changed according to the state of the headlight (switching between high beam and low beam, and the height of the optical axis). When the ECU 10 determines, based on the result of the glare determination unit 12, that glare is being generated for the driver of the preceding vehicle N due to the light of the headlight of the host vehicle M, it transmits the result to the lighting control unit 13 and issues an instruction to adjust the optical axis of the headlight.

[0020] Note that the glare determination unit 12 does not necessarily need to refer to the operation information of the automatic anti-glare mirror of the preceding vehicle N. The glare determination unit 12 may determine whether glare is being generated for the driver of the preceding vehicle N due to the light of the headlight of the host vehicle M based on the amount of glare from the rear (the direction where the host vehicle M is located) in the glare information of the preceding vehicle N and the distance between the host vehicle M and the preceding vehicle N.

[0021] The lighting control unit 13 controls the optical axis of the headlight of the host vehicle M. The lighting control unit 13 plays a role of issuing an instruction to adjust the optical axis of the headlight to the auto leveling mechanism 3 based on the determination result from the glare determination unit 12.

[0022] Specifically, when the glare determination unit 12 determines that glare is being generated for the driver of the preceding vehicle N, the lighting control unit 13 issues an instruction to lower the optical axis of the headlight (for example, the optical axis of the low beam) to the auto leveling mechanism 3. The auto leveling mechanism 3 adjusts the optical axis of the headlight to an appropriate angle in accordance with this instruction, suppressing the glare for the driver of the preceding vehicle N. The lighting control unit 13 repeats the instruction to lower the optical axis of the headlight at predetermined intervals until the glare determination unit 12 determines that no glare is being generated for the driver of the preceding vehicle N due to the light of the headlight of the host vehicle M.

[0023] Furthermore, the lighting control unit 13 also has a function to respond when glare is eliminated. Specifically, when the glare detection unit 12 determines that glare for the driver of the preceding vehicle N has been eliminated, the lighting control unit 13 instructs the auto-leveling mechanism 3 to return the headlight beam axis to its original position. This return operation is performed after a certain period of time has elapsed since the glare was eliminated and remains in that state. This suppresses the reduction in the driver's visibility caused by the headlight beam axis remaining lowered.

[0024] Next, an example of the configuration of the preceding vehicle N will be described. The preceding vehicle N can be any vehicle equipped with an automatic anti-glare mirror system and capable of transmitting glare information via vehicle-to-vehicle communication. The automatic anti-glare mirror system is a system that automatically controls the anti-glare mirror to reduce glare for the driver. The automatic anti-glare mirror system reduces glare for the driver by automatically adjusting the reflectivity and angle of the mirror. A well-known configuration can be used for the automatic anti-glare mirror system.

[0025] As shown in Figure 1, the preceding vehicle N is equipped with a glare sensor 5, a communication unit 6, and an ECU 20.

[0026] The glare sensor 5 is a sensor for detecting glare directed at the driver of the preceding vehicle N. Specifically, the glare sensor 5 is installed behind the preceding vehicle N and detects the degree of glare caused by the light emitted from the headlights of the vehicle M to the driver of the preceding vehicle N. The glare sensor 5 measures information such as the intensity and angle of the light and transmits this data to the ECU 20.

[0027] The communication unit 6 is mounted on the preceding vehicle N and is the component that performs vehicle-to-vehicle communication between the preceding vehicle N and the vehicle M. The communication unit 6 has the function of transmitting glare information generated by the glare calculation unit 21 to the vehicle M. Specifically, the communication unit 6 uses wireless communication technology to send and receive data with the communication unit 2 of the vehicle M. This allows the vehicle M to transmit glare information detected by the preceding vehicle N and information on the operation of the automatic dimming mirror. The communication unit 6 incorporates technologies to ensure the stability and reliability of communication so that the transmitted glare information is reliably delivered to the vehicle M.

[0028] Next, the functional configuration of the ECU20 will be described. The ECU20 has a glare calculation unit 21 and a glare information transmission unit 22.

[0029] The glare calculation unit 21 is mounted on the preceding vehicle N and calculates the amount of glare based on data transmitted from the glare sensor 5. Specifically, the glare calculation unit 21 receives information such as the intensity and angle of light detected by the glare sensor 5, analyzes this data, and calculates the amount of glare. The glare calculation unit 21 determines whether the calculated amount of glare exceeds a standard value, and if it does, generates glare information. This glare information includes the amount of glare and information on the operation of the automatic dimming mirror, and contains data that shows in detail the glare situation for the driver of the preceding vehicle N.

[0030] The glare information transmission unit 22 is mounted on the preceding vehicle N and transmits the glare information generated by the glare calculation unit 21 to the vehicle M. Specifically, the glare information transmission unit 22 uses wireless communication technology to send and receive data with the communication unit 2 of the vehicle M. The glare information transmission unit 22 transmits the glare information received from the glare calculation unit 21 to the vehicle M, which then delivers it to the glare information acquisition unit 11 of the vehicle M. As a result, the vehicle M can understand the glare situation for the driver of the preceding vehicle N and make appropriate adjustments to the headlight beam axis.

[0031] Next, we will explain the glare information generation process in the preceding vehicle N. Figure 2 is a flowchart showing an example of the glare information generation process in the ECU 20 of the preceding vehicle N.

[0032] As shown in Figure 2, in step S10, the ECU 20 first detects glare using the glare sensor 5. Specifically, the ECU 20 receives data from the glare sensor 5 and checks whether or not there is glare for the driver of the preceding vehicle N. If no glare is detected, the ECU 20 terminates this process.

[0033] Next, if glare is detected, the ECU 20 proceeds to step S11 to determine whether the detected amount of glare is equal to or greater than a reference value. Specifically, the ECU 20 analyzes the data from the glare sensor 5 and calculates the amount of glare. If this calculation result is less than the reference value, the ECU 20 returns to step S10 and continues to detect glare.

[0034] On the other hand, if the amount of glare is determined to be above a certain threshold, the ECU 20 proceeds to step S12 and generates glare information. Specifically, the ECU 20 creates glare information that includes information about the amount of glare and information about the operation of the automatic dimming mirror. This glare information is used as data to be transmitted to the vehicle M, which is following the preceding vehicle N.

[0035] Next, the processing in the ECU10 of the vehicle M will be explained. Figure 3 is a flowchart of an example of the glare suppression control start process in the ECU10 of the vehicle M. As shown in Figure 3, the ECU10 first receives glare information from the preceding vehicle N in step S20. Specifically, the ECU10 receives glare information transmitted from the communication unit 6 of the preceding vehicle N via the communication unit 2 and checks its contents. If no glare information is received from the preceding vehicle N, the ECU10 terminates the glare suppression control start process.

[0036] Next, the ECU 10 proceeds to step S21 and determines, based on the received glare information, whether glare is being generated for the driver of the preceding vehicle N due to the light from the headlights of its own vehicle M. Specifically, the ECU 10 analyzes the data from the glare information acquisition unit 11, and the glare determination unit 12 determines the status of glare generation. If this determination determines that no glare is being generated due to the light from the headlights of its own vehicle M, the ECU 10 terminates the glare suppression control start process.

[0037] On the other hand, if it is determined that glare is being generated by the headlights of the vehicle M, the ECU 10 proceeds to step S22 and starts glare suppression control. Specifically, the ECU 10 issues an instruction to the auto-leveling mechanism 3 via the lighting control unit 13 to lower the optical axis of the headlights. As a result, the optical axis of the headlights of the vehicle M is adjusted to an appropriate angle, and glare is suppressed for the driver of the preceding vehicle N.

[0038] Figure 4 is a flowchart showing an example of the glare suppression control termination process. The glare suppression control termination process is executed when glare suppression control is started in step S22 described above.

[0039] As shown in Figure 4, the ECU 10 first receives glare information from the preceding vehicle N in step S30. Specifically, the ECU 10 receives glare information transmitted from the communication unit 6 of the preceding vehicle N via the communication unit 2 and checks its contents. If the ECU 10 does not receive glare information (if a predetermined time has elapsed without receiving glare information from the preceding vehicle N), it proceeds to step S33.

[0040] Next, the ECU 10 proceeds to step S31 and determines, based on the received glare information, whether glare is being caused to the driver of the preceding vehicle N by the light from the headlights of its own vehicle M. Specifically, the ECU 10 analyzes the data from the glare information acquisition unit 11, and the glare determination unit 12 determines the status of glare occurrence. If this determination determines that glare is being caused by the light from the headlights of its own vehicle M, the ECU 10 proceeds to step S32. If it determines that glare is not being caused by the light from the headlights of its own vehicle M, the ECU 10 proceeds to step S33.

[0041] In step S32, the ECU 10 instructs the auto-leveling mechanism 3 via the lighting control unit 13 to further lower the headlight beam (for example, the low beam beam). This adjusts the headlight beam of the vehicle M to the appropriate angle, completely eliminating glare for the driver of the preceding vehicle N. The ECU 10 then returns to step S30 and repeats the process.

[0042] In step S33, the ECU 10 stops adjusting the beam axis of the vehicle M's headlights. Specifically, the ECU 10 issues a command to the auto-leveling mechanism 3 via the lighting control unit 13 to stop beam axis adjustment. This stops the process of continuously lowering the beam axis of the headlights.

[0043] Subsequently, the ECU10 proceeds to step S34 to determine whether a certain amount of time has elapsed with the optical axis adjustment stopped. Specifically, the ECU10 monitors the passage of a certain amount of time using an internal timer. If the required time has not elapsed, the ECU10 repeats step S34 and waits for the time to pass.

[0044] After a certain period of time has elapsed, the ECU 10 proceeds to step S35 and issues an instruction to return the headlight beam axis to its original position. Specifically, the ECU 10 issues an instruction to the auto-leveling mechanism 3 via the lighting control unit 13 to return the headlight beam axis to its original position. As a result, the headlight beam axis returns to its original position and the illumination returns to its normal state.

[0045] According to the vehicle lighting control system 100 of this embodiment described above, glare to the driver of the preceding vehicle N can be effectively suppressed by adjusting the optical axis of the headlights of the vehicle M based on glare information from the preceding vehicle N.

[0046] Furthermore, the vehicle lighting control system 100 enables more accurate glare detection by combining information on the operation of the automatic dimming mirror of the preceding vehicle N with distance information between the preceding vehicle N and the vehicle M. Specifically, if the automatic dimming mirror of the preceding vehicle is activated, this indicates that the driver of the preceding vehicle N is experiencing glare, and by using this information for glare detection, the glare situation can be grasped more accurately. In addition, by determining that glare has occurred when the distance between the preceding vehicle N and the vehicle M is less than a preset glare detection distance, appropriate glare suppression control according to the distance can be achieved. This makes it possible to effectively suppress glare for the driver of the preceding vehicle N.

[0047] Furthermore, according to the vehicle lighting control system 100, while it is determined that glare is occurring for the driver of the preceding vehicle N, the effect of glare can be effectively reduced by continuously or intermittently lowering the optical axis of the vehicle M's headlights. In addition, by continuing to appropriately adjust the optical axis until the glare is eliminated, the occurrence of glare for the driver of the preceding vehicle N can be minimized. Furthermore, once the glare is eliminated, the optical axis of the headlights can be returned to its original position to ensure the driver's visibility of the vehicle M.

[0048] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above. The present invention can be implemented in various forms, starting with the embodiments described above, by making various changes and improvements based on the knowledge of those skilled in the art.

[0049] The vehicle lighting control system 100 does not necessarily need to continuously lower the beam axis of the headlights. Adjustment of the beam axis of the headlights in glare suppression control may be done only once. The vehicle lighting control system 100 may not automatically return the beam axis of the headlights to its original position when glare detection is resolved.

[0050] In another embodiment of the present invention, the system may be configured to suppress glare to the driver of a preceding vehicle N by adjusting the light intensity of the headlights of the vehicle M, rather than lowering the optical axis of the headlights, based on glare information from a preceding vehicle N. Specifically, when the light control unit 13 determines, based on the glare determination unit 12, that the light from the headlights of the vehicle M is causing glare to the driver of the preceding vehicle N, it performs glare suppression control by reducing the brightness of the headlights instead of changing the optical axis of the headlights. This makes it possible to suppress glare without changing the optical axis of the headlights according to road conditions and driving environment, while maintaining visibility for the driver of the vehicle M. [Explanation of symbols]

[0051] 1...External sensor, 2...Communication unit, 3...Auto-leveling mechanism, 5...Glare sensor, 6...Communication unit, 10...ECU, 11...Glare information acquisition unit, 12...Glare determination unit, 13...Lighting control unit, 20...ECU, 21...Glare calculation unit, 22...Glare information transmission unit, M...Own vehicle, N...Preceding vehicle, 100...Vehicle lighting control system.

Claims

1. A vehicle lighting control system that controls the headlights of the vehicle, A glare information acquisition unit acquires glare information related to glare detected by a preceding vehicle traveling in front of the vehicle via vehicle-to-vehicle communication. A glare determination unit that determines whether or not the light from the headlights of the vehicle itself is causing glare to the driver of the preceding vehicle, based on the glare information obtained from the preceding vehicle, When the glare determination unit determines that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle, the lighting control unit executes glare suppression control to lower the optical axis of the headlights, A vehicle lighting control system equipped with the following features.

2. The vehicle lighting control system according to claim 1, wherein the glare determination unit determines that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle when the distance between the preceding vehicle and the vehicle itself is less than a preset glare determination distance, and the glare determination unit includes information on the operation of the automatic anti-glare mirror of the preceding vehicle in the glare information, and the vehicle determines that the light from the vehicle itself is causing glare to the driver of the preceding vehicle.

3. The vehicle lighting control system according to claim 1 or 2, wherein the lighting control unit continues to continuously or intermittently lower the optical axis of the headlights while the glare determination unit continues to determine that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle.

4. The vehicle lighting control system according to claim 1 or 2, wherein, after the lighting control unit has performed the glare suppression control, if a certain period of time has elapsed since the glare determination unit no longer determines that the light from the vehicle's headlights is causing glare to the driver of the preceding vehicle, the light axis of the headlights is returned to the state before the glare suppression control was performed.

Images