JP6952934B2 - Light distribution control system - Google Patents

Description

The present invention relates to a system for controlling the light distribution of vehicle headlights.

Vehicle headlights were controlled by a fixed light distribution pattern that only turned on / off the lights. Specifically, only low beam / high beam control was performed.
However, in recent years, techniques for forming various light distribution patterns, such as ADB, have been developed. ADB is used as follows.
The position of the vehicle in front is detected by the in-vehicle camera during high beam driving. Then, the ADB blocks the area where the vehicle in front is located, and the ADB irradiates the other areas with a high beam. The vehicles in front are the preceding vehicle and the oncoming vehicle in front.
ADB is an abbreviation for Adaptive Driving Beam.

The ADB has, for example, a plurality of LED light sources, and the brightness of the LED light sources can be individually adjusted. Therefore, the ADB can turn off or dimming each LED light source depending on the position where the vehicle in front is present.
LED is an abbreviation for Light Emitting Diode.

The number of LED light sources used in vehicle headlights is increasing in order to control light distribution control such as ADB more finely.
As the number of LED light sources to be controlled increases, the amount of control information notified from the light distribution control device to the headlight lighting device also increases. Therefore, the amount of control information may exceed the communication band of the in-vehicle network.
It is also conceivable to respond to the increase in the amount of control information by increasing the speed of the communication line. However, the speed improvement of the communication line applicable to the vehicle is limited, and it is difficult to change the communication line. Therefore, an effective data transfer method is required.

Patent Document 1 discloses a technique for reducing the amount of communication data for controlling each LED light source.
In this technique, a data structure in which the operation mode and the brightness data of each LED light source are associated with each other is maintained. Then, when the mode information is received when the operation mode is on, the data structure is referred to, and the state of each LED light source is determined according to the irradiation area specified by the mode information. As a result, the amount of communication data at one time is reduced as compared with the case where the luminance data itself of each LED light source is included in the mode information.
However, in this technique, processing when a plurality of operation modes are instructed to be turned on / off is not considered. Therefore, if the technique is used for a headlight having a plurality of operation modes, the operation mode cannot be uniquely determined.

Another method for reducing the amount of communication data is to compress the control data.
When increasing the compression rate of the control data, it is preferable to use lossy compression, for example, a JPEG method which is a still image compression method may be used.
JPEG is an abbreviation for Joint Photographic Experts Group.

Japanese Unexamined Patent Publication No. 2013-100015

If lossy compression such as that used for image compression is used to compress the control data, noise associated with the compression is generated and the control data changes.
In particular, there is a problem in reducing glare for vehicles in front. Specifically, due to the noise associated with compression, the control data instructing not to irradiate the light changes to the control data instructing to irradiate the light. As a result, the area where the vehicle in front exists is irradiated with light, which gives glare to the vehicle in front.

An object of the present invention is to make it possible to reduce glare given to a vehicle in front while suppressing the amount of control data.

The light distribution control system of the present invention is a system that controls the light distribution of the headlight of a vehicle having a variable light distribution type headlight.
The headlight has a plurality of light sources that illuminate a plurality of light irradiation areas constituting the light irradiation range in front of the vehicle.
The light distribution control system includes a light distribution control device and a lighting control device.
The light distribution control device is
A vehicle information acquisition unit that acquires driving environment information indicating the driving environment of the vehicle and obstacle information indicating an obstacle existing in front of the vehicle.
A brightness control unit that generates brightness control information that specifies the brightness that illuminates each light irradiation area based on the driving environment information.
A light irradiation control unit that generates light irradiation control information that specifies the necessity of light irradiation for each light irradiation region based on the obstacle information, and a light irradiation control unit.
It includes a control information transmitting unit that transmits the brightness control information and the light irradiation control information.
The lighting control device is
A control information receiving unit that receives the brightness control information and the light irradiation control information,
A lighting control unit that controls the lighting of each of the plurality of light sources based on the brightness control information and the light irradiation control information is provided.

According to the present invention, two types of control data, brightness control information and light irradiation control information, are generated. This makes it possible to compress the brightness control information and transmit it from the light distribution control device to the lighting control device, and transmit the light irradiation control information from the light distribution control device to the lighting control device without compressing it. That is, it is possible to reduce the glare given to the vehicle in front while suppressing the amount of control data.

The block diagram of the light distribution control system 100 in Embodiment 1. FIG. The block diagram of the light distribution control device 200 in Embodiment 1. FIG. The block diagram of the lighting control device 300 in Embodiment 1. FIG. The flowchart of the light distribution control process in Embodiment 1. The flowchart of the communication information generation processing (S140) in Embodiment 1. The figure which shows the light distribution notification parameter 291 in Embodiment 1. FIG. The flowchart of lighting control processing in Embodiment 1. The flowchart of the output information generation processing (S220) in Embodiment 1. The schematic diagram of the conversion method of obstacle information in Embodiment 1. The schematic diagram of the method of generating the light distribution control information in Embodiment 1. FIG. FIG. 3 is a hardware configuration diagram of the light distribution control device 200 according to the first embodiment. FIG. 3 is a hardware configuration diagram of the lighting control device 300 according to the first embodiment.

In embodiments and drawings, the same or corresponding elements are designated by the same reference numerals. The description of the elements with the same reference numerals as the described elements will be omitted or abbreviated as appropriate. The arrows in the figure mainly indicate the flow of data or the flow of processing.

Embodiment 1.
The light distribution control system 100 that controls the light distribution of the headlights of the vehicle will be described with reference to FIGS. 1 to 12.

*** Explanation of configuration ***
The configuration of the light distribution control system 100 will be described with reference to FIG.
The light distribution control system 100 is a system mounted on a vehicle, and includes a sensor group 110, a communication device 120, a light distribution control device 200, a lighting control device (300L, 300R), and a headlight (190L, 190R). ..
Specifically, the light distribution control system 100 is mounted on an automobile.

The sensor group 110 is one or more sensors, and includes an in-vehicle camera 111, a radar device 112, a steering angle sensor 113, a vehicle speed sensor 114, and the like.
The in-vehicle camera 111 is a sensor that captures the surroundings (particularly in front of) the vehicle.
The radar device 112 is a sensor that measures the distance to an object existing around the vehicle and the direction in which the object is located.
The steering angle sensor 113 is a sensor that measures the steering direction.
The vehicle speed sensor 114 is a sensor that measures the speed of the vehicle.

The communication device 120 is a device that communicates with various devices outside the vehicle via a network outside the vehicle (for example, the Internet).
For example, the communication device 120 communicates with a server device, a roadside machine, another vehicle, a diagnostic device, or the like. A diagnostic device is a device used for maintenance and inspection of automobiles.

The light distribution control device 200 is a device that controls the light distribution of the headlights (190L, 190R).
The light distribution control device 200 communicates with the sensor group 110, the communication device 120, and the lighting control device (300L, 300R) via the network 101.
The network 101 is a network in the vehicle. In the communication performed via the network 101, a communication protocol such as LIN or CAN is used.
LIN is an abbreviation for Local Interconnect Network.
CAN is an abbreviation for Controller Area Network.

Headlights (190L, 190R) are lighting devices that illuminate the front of the vehicle.
The headlight on the left side is referred to as "headlight 190L", and the headlight on the right side is referred to as "headlight 190R". If any of the headlights is not specified, each is referred to as "headlight 190".

The range illuminated by the headlight 190 is referred to as a "light irradiation range".
The light irradiation range is composed of a plurality of light irradiation regions. The plurality of light irradiation regions are a plurality of regions that divide the light irradiation region.

The headlight 190 is a variable light distribution type headlight, and has a plurality of light sources that illuminate a plurality of light irradiation areas. A device having a plurality of light sources and constituting the headlight 190 is called a "light irradiation device". A light source is one that irradiates light by emitting or reflecting light.
For example, each light source is an LED light source or DMD. DMD is an abbreviation for Digital Mirror Device.

The lighting control device (300L, 300R) is a device that controls the lighting of each of a plurality of light sources provided in the headlight 190.
The lighting control device for the headlight 190L is referred to as "lighting control device 300L", and the lighting control device for the headlight 190R is referred to as "lighting control device 300R". When any of the lighting control devices is not specified, each is referred to as "lighting control device 300".

The configuration of the light distribution control device 200 will be described with reference to FIG.
The light distribution control device 200 is a computer including hardware such as a processor 201, a memory 202, an auxiliary storage device 203, and a communication interface 204. These hardware are connected to each other via signal lines.

The processor 201 is an IC that performs arithmetic processing and controls other hardware. For example, the processor 201 is a CPU.
IC is an abbreviation for Integrated Circuit.
CPU is an abbreviation for Central Processing Unit.

The memory 202 is a volatile storage device. The memory 202 is also referred to as a main storage device or a main memory. For example, the memory 202 is a RAM. The data stored in the memory 202 is stored in the auxiliary storage device 203 as needed.
RAM is an abbreviation for Random Access Memory.

The auxiliary storage device 203 is a non-volatile storage device. For example, the auxiliary storage device 203 is a ROM, HDD, or flash memory. The data stored in the auxiliary storage device 203 is loaded into the memory 202 as needed.
ROM is an abbreviation for Read Only Memory.
HDD is an abbreviation for Hard Disk Drive.

The communication interface 204 is an interface for performing communication via the network 101, and is connected to the network 101.

The light distribution control device 200 includes elements such as a vehicle information acquisition unit 210, a light distribution control unit 220, and a control information transmission unit 230. These elements are realized in software.
The light distribution control unit 220 includes a brightness control unit 221 and a light irradiation control unit 222.
The control information transmission unit 230 includes a communication information generation unit 231 and a communication processing unit 232.

The auxiliary storage device 203 stores a light distribution control program for operating a computer as a vehicle information acquisition unit 210, a light distribution control unit 220, and a control information transmission unit 230. The light distribution control program is loaded into the memory 202 and executed by the processor 201.
The OS is further stored in the auxiliary storage device 203. At least part of the OS is loaded into memory 202 and executed by processor 201.
The processor 201 executes the light distribution control program while executing the OS.
OS is an abbreviation for Operating System.

The input / output data of the light distribution control program is stored in the storage unit 290.
The memory 202 functions as a storage unit 290. However, a storage device such as an auxiliary storage device 203, a register in the processor 201, and a cache memory in the processor 201 may function as a storage unit 290 instead of the memory 202 or together with the memory 202.

The light distribution control device 200 may include a plurality of processors that replace the processor 201. The plurality of processors share the role of the processor 201.

The light distribution control program can record (store) in a non-volatile recording medium such as an optical disk or a flash memory so that it can be read by a computer.

The configuration of the lighting control device 300 will be described with reference to FIG.
The lighting control device 300 is a computer including hardware such as a processor 301, a memory 302, an auxiliary storage device 303, a communication interface 304, and an input / output interface 305. These hardware are connected to each other via signal lines.

The processor 301 is an IC that performs arithmetic processing and controls other hardware. For example, the processor 301 is a CPU.
The memory 302 is a volatile storage device. The memory 302 is also referred to as a main storage device or a main memory. For example, the memory 302 is a RAM. The data stored in the memory 302 is stored in the auxiliary storage device 303 as needed.
The auxiliary storage device 303 is a non-volatile storage device. For example, the auxiliary storage device 303 is a ROM, HDD, or flash memory. The data stored in the auxiliary storage device 303 is loaded into the memory 302 as needed.
The communication interface 304 is an interface for performing communication via the network 101, and is connected to the network 101.
The input / output interface 305 is an interface connected to the headlight 190.

The lighting control device 300 includes elements such as a control information receiving unit 310 and a lighting control unit 320. These elements are realized in software.
The control information receiving unit 310 includes a communication processing unit 311.
The lighting control unit 320 includes an output information generation unit 321 and a light source lighting unit 322.

The auxiliary storage device 303 stores a lighting control program for operating the computer as the control information receiving unit 310 and the lighting control unit 320. The lighting control program is loaded into the memory 302 and executed by the processor 301.
The OS is further stored in the auxiliary storage device 303. At least part of the OS is loaded into memory 302 and executed by processor 301.
The processor 301 executes the lighting control program while executing the OS.

The input / output data of the lighting control program is stored in the storage unit 390.
The memory 302 functions as a storage unit 390. However, a storage device such as an auxiliary storage device 303, a register in the processor 301, and a cache memory in the processor 301 may function as a storage unit 390 instead of the memory 302 or together with the memory 302.

The lighting control device 300 may include a plurality of processors that replace the processor 301. The plurality of processors share the role of the processor 301.

The lighting control program can be computer-readablely recorded (stored) on a non-volatile recording medium such as an optical disk or a flash memory.

*** Explanation of operation ***
The operation of the light distribution control system 100 corresponds to the light distribution control method.
In the light distribution control method, the process executed by the light distribution control device 200 is referred to as "light distribution control process".
In the light distribution control method, the process executed by the lighting control device 300 is referred to as "lighting control process".

First, an outline of the light distribution control method will be described.
The vehicle information acquisition unit 210 acquires the traveling environment information indicating the traveling environment of the vehicle and the obstacle information indicating the obstacle existing in front of the vehicle.
The brightness control unit 221 generates brightness control information that specifies the brightness that illuminates each light irradiation region based on the traveling environment information.
The light irradiation control unit 222 generates light irradiation control information that specifies the necessity of light irradiation for each light irradiation region based on the obstacle information.
The control information transmission unit 230 transmits the brightness control information and the light irradiation control information.
The control information receiving unit 310 receives the brightness control information and the light irradiation control information.
The lighting control unit 320 controls the lighting of each of the plurality of light sources based on the brightness control information and the light irradiation control information.
The details of the light distribution control method will be described below.

The light distribution control process will be described with reference to FIG.
In step S110, the vehicle information acquisition unit 210 acquires vehicle information from the sensor group 110.
The vehicle information includes vehicle state information and vehicle peripheral information.
The vehicle state information is information indicating the state (behavior) of the vehicle. For example, the vehicle state information indicates the input state of the headlight, the vehicle speed, the acceleration, the steering angle of the steering wheel, and the like.
The vehicle peripheral information is information indicating the environment around the vehicle, and includes driving environment information and obstacle information.
The driving environment information indicates the driving environment of the vehicle. The traveling environment of the vehicle corresponds to the situation in which the vehicle is traveling. For example, the driving environment information indicates a luminescent material, a reflecting object, a time zone, a weather, a driving road, and the like. A specific example of a luminescent material is a traffic light. A specific example of a reflector is a road sign. Roads are classified into general roads and highways. General roads are classified into urban roads and suburban roads.
Obstacle information is information indicating an obstacle existing in front of the vehicle. For example, obstacle information indicates obstacles such as vehicles in front, pedestrians, animals and falling objects. These obstacles are subject to shading or light irradiation.

In step S120, the brightness control unit 221 generates brightness control information based on the vehicle state information and the traveling environment information.
The brightness control information specifies the brightness that illuminates each light irradiation area. Specifically, the brightness control information indicates a brightness value for each light irradiation region. The brightness value is a value representing brightness.

For example, each light irradiation area is an individual irradiation range of a plurality of LED light sources constituting the headlight 190. However, the light irradiation range of the headlight 190 may be divided regardless of the number of LED light sources. That is, the light irradiation range of the headlight 190 may be divided by an arbitrary resolution to determine a plurality of light irradiation areas. For example, the light irradiation range may be divided by a resolution such as "width 128 x height 32".

The brightness control information may be in any format as long as the brightness that illuminates each light irradiation area can be specified.
For example, the brightness is expressed in 100 steps of "0% to 100%". "%" Means percentage. However, the brightness may be expressed in another way such as 256 steps.

Specifically, the brightness control unit 221 determines the light irradiation state according to the driving environment based on the vehicle state information and the traveling environment information. Then, the brightness control unit 221 generates brightness control information according to the determined light irradiation state.
The determined light irradiation state is a target light irradiation state for each light irradiation region.

For example, the brightness control unit 221 determines the light irradiation state according to each traveling environment as follows.
In order to ensure visibility of the traveling direction of the vehicle, the brightness control unit 221 determines the traveling direction of the vehicle by using the steering angle information of the steering wheel included in the vehicle state information. Then, the brightness control unit 221 determines a light irradiation state that makes the traveling direction side of the vehicle the brightest and darkens the side side of the vehicle.
In order to prevent glare due to the reflected light from the road sign, the brightness control unit 221 detects the road sign existing around the vehicle by using the traveling environment information. Then, the brightness control unit 221 determines a light irradiation state that darkens the portion where the road sign exists.
The brightness control unit 221 determines a light irradiation state that changes the brightness of the headlight 190 and the light irradiation range of the headlight 190 according to the brightness of a time zone such as evening or midnight.
The brightness control unit 221 determines a light irradiation state that changes the brightness of the headlight 190 and the light irradiation range of the headlight 190 according to the intensity of the reflected light from the road surface in fine weather or rainy weather. do.
When traveling in an urban area, the brightness control unit 221 determines a wide light irradiation state in the lateral direction in order to facilitate detection of pedestrians in the vicinity.
When traveling on a highway, the brightness control unit 221 determines a narrow light irradiation state centered on the traveling direction.
When the light irradiation device constituting the headlight 190 can change the color, the brightness control unit 221 determines not only the brightness but also the color (RGB value).

As illustrated, the brightness control unit 221 determines a plurality of light irradiation states according to a plurality of types of driving environments indicated by the traveling environment information. Then, the brightness control unit 221 synthesizes (integrates) a plurality of light irradiation states to determine the target light irradiation state of the light irradiation range, and the brightness control information is matched to the target light irradiation state of the light irradiation range. To generate. The generated brightness control information indicates the target light irradiation state in the light irradiation range.

In step S130, the light irradiation control unit 222 generates light irradiation control information based on the vehicle state information and the obstacle information.
The light irradiation control information specifies the necessity of light irradiation for each light irradiation region. Specifically, the light irradiation control information has a light irradiation flag for each light irradiation region. The light irradiation flag indicates shading or light irradiation.

Specifically, the light irradiation control unit 222 determines the light irradiation state according to the presence or absence of an obstacle by using the vehicle state information and the obstacle information. Then, the light irradiation control unit 222 generates the light irradiation control information according to the determined light irradiation state.

For example, the light irradiation control unit 222 determines the light irradiation state according to the presence or absence of an obstacle as follows.
When the vehicle in front is present, the light irradiation control unit 222 determines a light irradiation state such that the light irradiation region in which the vehicle in front is present is shielded from light and the other light irradiation region is irradiated with light.
When a pedestrian, an animal, or a falling object is present in front of the vehicle, the light irradiation control unit 222 illuminates the light irradiation area where the pedestrian, the animal, or the falling object is present in order to spot-emphasize and illuminate the obstacle. The light irradiation state is determined so as to irradiate and block other light irradiation areas.

As described above, the brightness control information is generated by synthesizing a plurality of light irradiation states according to various driving environments.
On the other hand, the light irradiation control information is generated for one light irradiation state according to the presence or absence of an obstacle.

There are two types of light irradiation control information: information for shading the light irradiation area where an obstacle (vehicle in front) exists, and information for light irradiation of a light irradiation area where an obstacle (pedestrian, etc.) exists. It may be information.
Shading and light irradiation can be represented by 1 bit. For example, shading is represented by "0" and light irradiation is represented by "1".

In step S140, the communication information generation unit 231 generates communication information based on the brightness control information and the light irradiation control information.
The communication information is information including brightness control information and light irradiation control information, and is transmitted to the lighting control device 300.
The details of the communication information generation process (S140) will be described later.

In step S150, the communication processing unit 232 transmits the communication information to the lighting control device 300.

The details of the communication information generation process (S140) will be described with reference to FIG.
The brightness control information and the light irradiation control information are collectively referred to as "light distribution control information".
The light distribution control information is edited based on the light distribution notification parameter 291. Specifically, the light distribution control information is synthesized. In addition, the light distribution control information is compressed.

In step S141, the communication information generation unit 231 acquires the light distribution notification parameter 291 from the storage unit 290.

The light distribution notification parameter 291 will be described with reference to FIG.
The light distribution notification parameter 291 includes a composite parameter and a compression parameter.
The synthesis parameter specifies the necessity of synthesizing the light distribution control information.
The compression parameter specifies whether or not the light distribution control information should be compressed and the compression method.
The compression method is specified by a combination of a compression method and a compression quality.
The compression method indicates a compression algorithm such as LZMA, JPEG, or lossless-JPEG.
It is better not to compress the light irradiation control information in order to avoid inversion of the value due to noise caused by compression.

Returning to FIG. 5, the description continues from step S142.
In step S142, the communication information generation unit 231 determines the necessity of synthesizing the light distribution control information based on the synthesis parameters.
If it is necessary to synthesize the light distribution control information, the process proceeds to step S143.
If it is not necessary to synthesize the light distribution control information, the process proceeds to step S144.

In step S143, the communication information generation unit 231 synthesizes the light distribution control information.
That is, the communication information generation unit 231 synthesizes the brightness control information and the light irradiation control information.

The communication information generation unit 231 synthesizes the brightness control information and the light irradiation control information as follows.
First, the communication information generation unit 231 processes the light irradiation control information. Specifically, the communication information generation unit 231 replaces the flag value indicating that light irradiation is required for each light irradiation region that requires light irradiation with the maximum value of brightness (for example, 100). Further, the communication information generation unit 231 replaces the flag value indicating that light irradiation is unnecessary with the minimum value of brightness (for example, 0) for each light irradiation region that does not require light irradiation.
Then, the communication information generation unit 231 adds the value of the light irradiation control information to the value of the brightness control information for each light irradiation region.

In step S144, the communication information generation unit 231 determines whether or not the light distribution control information needs to be compressed based on the compression parameters.
If it is necessary to compress the light distribution control information, the process proceeds to step S145.
If it is not necessary to compress the light distribution control information, the process proceeds to step S146.

In step S145, the communication information generation unit 231 compresses the light distribution control information according to the compression parameter.

The communication information generation unit 231 compresses the light distribution control information as follows.
When the compression algorithm specified by the compression parameter is an image compression algorithm such as JPEG, the communication information generation unit 231 converts the light distribution control information into an image format such as PGM format. Then, the communication information generation unit 231 compresses the light distribution control information after being converted into the image format by the image compression algorithm.
When converting the light distribution control information into the PGM format, the communication information generation unit 231 adds the header information in the PGM format to the light distribution control information. The header information in the PGM format includes the magic number "P2", the light irradiation area information corresponding to the resolution information (width and height), and the maximum value of brightness (for example, 100). The light irradiation area information indicates the number of vertical and horizontal divisions of the light irradiation range.

In step S146, the communication information generation unit 231 generates communication information including the light distribution control information.

Specifically, the communication information generation unit 231 adds various information such as compressed information, an information identifier, and a maximum value of resolution and brightness to the light distribution control information. The light distribution control information to which various information is added becomes the communication information.
The compression information indicates the presence or absence of compression and the compression method.
The information identifier indicates the type of light distribution control information. For example, the information identifier can be divided into categories such as "0: composite information", "1: brightness control information", "2: light irradiation control information <shading>", and "3: light irradiation control information <light irradiation>". show.
The resolution indicates the number of vertical and horizontal divisions of the light irradiation range. When the light source and the light irradiation region have a one-to-one correspondence, "0" is set as the number of divisions.
The maximum value of brightness is "100" when the brightness is shown in 100 steps, and "255" when the brightness is shown in 255 steps. The maximum value of the brightness of the light irradiation control information is "1".

Supplementary information on light distribution control processing.
When considering a general driving situation, the obstacle information changes faster than the driving environment information changes. Therefore, the brightness control information based on the traveling environment information and the light irradiation control information based on the obstacle information may be generated at different cycles. For example, the brightness control information may be generated in a cycle of 500 milliseconds, and the light irradiation control information may be generated in a cycle of 50 milliseconds.
When the brightness control information and the light irradiation control information are generated at different cycles, the communication information generation unit 231 stores the latest brightness control information in the storage unit 290. Then, when synthesizing the light distribution control information, the communication information generation unit 231 uses the latest stored brightness control information. However, when it is not necessary to synthesize the light distribution control information, it is not necessary to save the latest brightness control information.
The communication information generation unit 231 calculates the difference between the previous brightness control information and the current brightness control information, and the communication processing unit 232 transmits the difference between the previous brightness control information and the current brightness control information. You may. In this case, the difference identification information that identifies whether the brightness control information is the total information or the difference information is added to the communication information. However, the communication processing unit 232 transmits the entire brightness control information at regular intervals. For example, the communication processing unit 232 transmits the difference in the brightness control information three times out of the four transmissions, and transmits the entire brightness control information the remaining one time.

The lighting control process will be described with reference to FIG. 7.
In step S210, the communication processing unit 311 receives the communication information from the light distribution control device 200.

In step S220, the output information generation unit 321 generates output information based on the communication information, and notifies the light source lighting unit 322 of the generated output information.
The output information is information that specifies the brightness of each of the plurality of light sources constituting the headlight 190.
The details of the output information generation process (S220) will be described later.

In step S230, the light source lighting unit 322 controls the lighting of each of the plurality of light sources constituting the headlight 190 based on the notified output information.
That is, the light source lighting unit 322 turns on (or turns off) each of the plurality of light sources constituting the headlight 190 with the brightness specified in the output information.

The details of the output information generation process (S220) will be described with reference to FIG.
In step S221, the output information generation unit 321 acquires the headlight configuration parameters from the storage unit 390.
The headlight configuration parameter is data indicating the configuration of the headlight 190, that is, the configuration of a plurality of light sources constituting the headlight 190. Specifically, the headlight configuration parameters indicate the light source type and the resolution.
The light source type indicated by the headlight configuration parameter is the type of the light source used in the headlight 190. For example, the type of light source is LED light source or DMD.
The resolution indicated by the headlight configuration parameter is the resolution of the light irradiation range of the headlight 190, and indicates the number of light sources in the width direction and the number of light sources in the height direction. The light irradiation range is represented by, for example, the respective angles in the width direction and the height direction, or the respective lengths in the width direction and the height direction.

In step S222, the output information generation unit 321 acquires the compressed information from the communication information.

In step S223, the output information generation unit 321 determines whether or not the light distribution control information is compressed based on the compression information.
If the light distribution control information is compressed, the process proceeds to step S224.
If the light distribution control information is not compressed, the process proceeds to step S225.

In step S224, the output information generation unit 321 decompresses the compressed light distribution control information based on the compression method shown in the compression information.

When the compression algorithm shown in the compression information is an image compression algorithm such as JPEG, the output information generation unit 321 acquires the light distribution control information by the image conversion process. The image conversion process is a conventional technique.
For example, when the compression algorithm shown in the compression information is JPEG, the output information generation unit 321 converts the JPEG format light distribution control information into the PGM format, and acquires the PGM format header information and the light distribution control information. ..

In step S225, the output information generation unit 321 converts the light distribution control information into output information.

The output information generation unit 321 performs the conversion as follows.
First, the output information generation unit 321 determines the type of light distribution control information based on the information identifier included in the communication information.
When the light distribution control information is the light irradiation control information, the light distribution control information has a light irradiation flag for each light irradiation region. The light irradiation flag is 1-bit information and indicates shading or light irradiation. The output information generation unit 321 converts the value “1” of the light irradiation flag indicating light irradiation into a value meaning “100%”. Further, the output information generation unit 321 converts the value "0" of the light irradiation flag indicating shading into a value meaning "0%".

When the light distribution control information is not synthetic information, the light distribution control information includes brightness control information and light irradiation control information separately. In this case, the output information generation unit 321 may combine the brightness control information and the light irradiation information and output them, or may output them separately without combining them.

A case where the output information generation unit 321 synthesizes the brightness control information and the light irradiation information will be described.
The output information generation unit 321 synthesizes the latest light distribution control information (brightness control information and light irradiation control information) at a fixed cycle (for example, 5 ms cycle) to generate output information, and lights the generated output information as a light source. Notify unit 322.
At the time of synthesis, the output information generation unit 321 converts the value of each light irradiation flag of the light irradiation control information into the brightness value for the brightness control information. Specifically, the output information generation unit 321 converts the value "1" of the light irradiation flag indicating light irradiation into the maximum value of brightness.

A case where the light source and the light irradiation region have a one-to-one correspondence will be described.
The output information generation unit 321 determines whether the resolution indicated in the communication information is "0".
When the resolution indicated in the communication information is "0", the light source and the light irradiation region have a one-to-one correspondence. Therefore, the output information generation unit 321 handles the light distribution control information as it is as output information.

A case where the light source and the light irradiation region do not have a one-to-one correspondence will be described.
The output information generation unit 321 determines whether the resolution indicated in the communication information is "0".
When the resolution shown in the communication information is other than "0", there is no one-to-one correspondence between the light source and the light irradiation area. Therefore, the output information generation unit 321 generates output information based on the light distribution control information and the resolution indicated by the headlight configuration parameter.
For example, it is assumed that the resolution indicated in the communication information is "128 x 32" and the resolution indicated in the headlight configuration parameter is "64 x 16". In this case, the output information generation unit 321 allocates a “2 × 2” light irradiation region to one light source based on the headlight configuration parameters. When the “2 × 2” light irradiation region includes a light irradiation region in which the maximum value of brightness is specified, the output information generation unit 321 determines the maximum value of brightness as the control value of the light source. When the “2 × 2” light irradiation region includes a light irradiation region in which the minimum value of brightness is specified, the output information generation unit 321 determines the minimum value of brightness as the control value of the light source. When the “2 × 2” light irradiation area does not include the light irradiation area in which the maximum value or the minimum value of the brightness is specified, the output information generation unit 321 uses the “2 × 2” light irradiation area. The average value of the brightness in is determined as the control value of the light source.

A case where the output information generation unit 321 does not combine the brightness control information and the light irradiation information will be described.
The output information generation unit 321 generates output information at the timing when the communication information is received, and notifies the light source lighting unit 322 of the generated output information.
When the information identifier included in the communication information indicates "brightness control information", the output information generation unit 321 notifies the light source lighting unit 322 of the difference between the output information previously notified and the output information generated this time.
When the information identifier included in the communication information indicates "light irradiation control information <light shielding>", the output information generation unit 321 notifies the light source lighting unit 322 of the output information only in the light irradiation region for which shading is specified.
When the information identifier included in the communication information indicates "light irradiation control information <light irradiation>", the output information generation unit 321 notifies the light source lighting unit 322 of the output information of only the light irradiation region for which light irradiation is specified. ..
When the difference identification information included in the communication information indicates "difference in brightness control information", the output information generation unit 321 notifies the light source lighting unit 322 of the difference between the output information previously notified and the output information generated this time. ..

The method of identifying the position of the obstacle will be described below.
The obstacle information acquired by the vehicle information acquisition unit 210 indicates the relative position of the obstacle with respect to the vehicle. The relative position is represented by the distance from the vehicle in the traveling direction, the distance from the vehicle in the horizontal direction orthogonal to the traveling direction, and the distance from the vehicle in the height direction.
When the light irradiation range of the headlight 190 is divided by a resolution such as "width 128 x height 32" and a plurality of light irradiation areas are determined, three-dimensional obstacle information is converted into two-dimensional obstacle information. This facilitates the generation of light distribution control information.

A method of converting three-dimensional obstacle information into two-dimensional obstacle information will be described with reference to FIG.
The light distribution control unit 220 converts the three-dimensional position (X, Y, Z) of the obstacle into the two-dimensional image position (H, V) at a certain projection distance, for example, by perspective projection conversion. Perspective projection transformation is a prior art. (X, Y) and (H) indicate horizontal coordinate values, and (Z) and (V) indicate vertical coordinate values. A projection distance of about 25 meters is suitable for the perspective projection conversion. When the projection distance used in the perspective projection conversion is 25 meters, the light distribution control of the headlight 190 corresponds to the control of the light distribution to the virtual screen 25 meters away. When the light source used for the headlight 190 is an LED light source, the light irradiation range of the headlight 190 may be divided into a plurality of light irradiation regions based on the light irradiation range of each LED light source for the virtual screen. The information of this division is set in the definition information (headlight configuration parameter) of the lighting control device 300. In addition, the number of divisions is used for light distribution control information.

A method of generating light distribution control information based on two-dimensional obstacle information will be described with reference to FIG.
As described above, the three-dimensional position (X, Y, Z) of the obstacle is converted into the two-dimensional image position (H, V).
The area where the obstacle exists is represented by four two-dimensional image positions (H, V) indicating the four vertices of the obstacle. The area sandwiched between the four vertices is the area where obstacles exist.
Then, the four two-dimensional image positions (H, V) representing the area where the obstacle exists are the indicated values (light shielding) of the light distribution control information. As a result, the area where the obstacle exists is shielded from light.

The in-vehicle camera 111 will be described.
The in-vehicle camera 111 generates an image by photographing, recognizes an object such as a pedestrian, an automobile, and a road sign reflected in the generated image, and outputs information indicating an area in which the recognized object is reflected. In recent years, research on a method called semantic segmentation has progressed, and it has become possible to label each object such as a pedestrian, a car, or a road sign on a pixel-by-pixel basis of an image.
When each object can be labeled on a pixel-by-pixel basis, the light irradiation state can be determined on a pixel-by-pixel basis. Specifically, the brightness control information can be generated by using the conversion information for converting the label attached to each area into the brightness value. For example, the label "pedestrian" is converted to the maximum brightness value, the label "automobile" is converted to the minimum brightness value, and the label "road surface" is converted to an intermediate brightness value.
In this case, it is necessary to convert the resolution of the vehicle-mounted camera 111 into the resolution of the light distribution control information. It is assumed that the resolution of the vehicle-mounted camera 111 is "128 x 32" and the resolution of the light distribution control information is "64 x 16". In this case, the “2 × 2” region of the vehicle-mounted camera 111 is associated with one region in the light distribution control information. When a plurality of labels are given to the "2x2" area of the vehicle-mounted camera 111, it is preferable to determine the object existing in the "2x2" area based on the priority of the object indicated by the label. For example, it is desirable to give a high priority to an object that needs to be recognized by the driver, such as "pedestrian>bicycle>motorcycle>automobile> road surface". Further, if the position of the pedestrian's face (or eyes) can be specified, the priority of the pedestrian's face (or eyes) may be set higher than that of other parts of the pedestrian. By doing so, it is possible to perform fine light distribution such that the area where the pedestrian's face (or eyes) exists is shielded from light and the area where the other part of the pedestrian exists is irradiated with light.

*** Effect of Embodiment 1 ***
According to the first embodiment, it is possible to reduce the glare given to the vehicle in front while suppressing the amount of data of the light distribution control information.
The light distribution control device 200 can compress the brightness control information and transmit it to the lighting control device 300. As a result, the amount of information transmitted from the light distribution control device 200 to the lighting control device 300 can be reduced.
The light distribution control device 200 can transmit the light irradiation control information to the lighting control device 300 without compressing it. Therefore, the necessity of light irradiation shown in the light irradiation control information is not reversed by the noise accompanying the compression. This makes it possible to prevent the vehicle in front from being irradiated with strong light.

*** Supplement to Embodiment 1 ***
The communication device 120 can communicate with a diagnostic device outside the vehicle. The light distribution control program, the lighting control program, the light distribution notification parameter 291 and the headlight configuration parameter can be rewritten from the diagnostic device.
The communication device 120 can communicate with a server device connected to the Internet. The light distribution control program, the lighting control program, the light distribution notification parameter 291 and the headlight configuration parameter can be rewritten from the server device.

The hardware configuration of the light distribution control device 200 will be described with reference to FIG.
The light distribution control device 200 includes a processing circuit 209.
The processing circuit 209 is hardware that realizes the vehicle information acquisition unit 210, the light distribution control unit 220, and the control information transmission unit 230.
The processing circuit 209 may be dedicated hardware or a processor 201 that executes a program stored in the memory 202.

When the processing circuit 209 is dedicated hardware, the processing circuit 209 is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof.
ASIC is an abbreviation for Application Special Integrated Circuit.
FPGA is an abbreviation for Field Programmable Gate Array.

The light distribution control device 200 may include a plurality of processing circuits that replace the processing circuit 209. The plurality of processing circuits share the role of the processing circuit 209.

In the light distribution control device 200, some functions may be realized by dedicated hardware, and the remaining functions may be realized by software or firmware.

In this way, the processing circuit 209 can be realized by hardware, software, firmware or a combination thereof.

The hardware configuration of the lighting control device 300 will be described with reference to FIG.
The lighting control device 300 includes a processing circuit 309.
The processing circuit 309 is hardware that realizes the control information receiving unit 310 and the lighting control unit 320.
The processing circuit 309 may be dedicated hardware or a processor 301 that executes a program stored in the memory 302.

When the processing circuit 309 is dedicated hardware, the processing circuit 309 is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination thereof.
ASIC is an abbreviation for Application Special Integrated Circuit.
FPGA is an abbreviation for Field Programmable Gate Array.

The lighting control device 300 may include a plurality of processing circuits that replace the processing circuit 309. The plurality of processing circuits share the role of the processing circuit 309.

In the lighting control device 300, some functions may be realized by dedicated hardware, and the remaining functions may be realized by software or firmware.

In this way, the processing circuit 309 can be realized by hardware, software, firmware or a combination thereof.

The embodiments are examples of preferred embodiments and are not intended to limit the technical scope of the invention. The embodiment may be partially implemented or may be implemented in combination with other embodiments. The procedure described using the flowchart or the like may be appropriately changed.

The lighting control device 300L and the lighting control device 300R may be realized by one device.
The "unit" which is an element of each of the light distribution control device 200 and the lighting control device 300 may be read as "process" or "process".

100 light distribution control system, 101 network, 110 sensor group, 111 in-vehicle camera, 112 radar device, 113 steering angle sensor, 114 vehicle speed sensor, 120 communication device, 190 headlight, 200 light distribution control device, 201 processor, 202 memory , 203 auxiliary storage device, 204 communication interface, 209 processing circuit, 210 vehicle information acquisition unit, 220 light distribution control unit, 221 brightness control unit, 222 light irradiation control unit, 230 control information transmission unit, 231 communication information generation unit, 232 communication processing unit, 290 storage unit, 291 light distribution notification parameter, 300 lighting control device, 301 processor, 302 memory, 303 auxiliary storage device, 304 communication interface, 305 input / output interface, 309 processing circuit, 310 control information receiving unit, 311 communication processing unit, 320 lighting control unit, 321 output information generation unit, 322 light source lighting unit, 390 storage unit.

Claims (8)

It is a light distribution control system that controls the light distribution of the headlight of a vehicle having a variable light distribution type headlight.
The headlight has a plurality of light sources that illuminate a plurality of light irradiation areas constituting the light irradiation range in front of the vehicle.
The light distribution control system includes a light distribution control device and a lighting control device.
The light distribution control device is
A vehicle information acquisition unit that acquires driving environment information indicating the driving environment of the vehicle and obstacle information indicating an obstacle existing in front of the vehicle.
A brightness control unit that generates brightness control information that specifies the brightness that illuminates each light irradiation area based on the driving environment information.
A light irradiation control unit that generates light irradiation control information that specifies the necessity of light irradiation for each light irradiation region based on the obstacle information, and a light irradiation control unit.
A control information transmitting unit for transmitting the brightness control information and the light irradiation control information is provided.
The lighting control device is
A control information receiving unit that receives the brightness control information and the light irradiation control information,
A lighting control unit that controls the lighting of each of the plurality of light sources based on the brightness control information and the light irradiation control information.
Light distribution control system equipped with. The light distribution control system includes a communication device that communicates with an external device via an external network.
The control information transmission unit edits the brightness control information and the light irradiation control information based on the light distribution notification parameter, and transmits the edited brightness control information and the edited light irradiation control information.
The light distribution control system according to claim 1, wherein the light distribution notification parameter is rewritten by the external device via the communication device. The control information transmitting unit compresses and transmits the brightness control information, and transmits the light irradiation control information without compressing the light irradiation control information.
The control information receiving unit receives the compressed brightness control information and the light irradiation control information, and receives the compressed brightness control information.
The lighting control unit expands the compressed brightness control information and controls the lighting of each of the plurality of light sources based on the expanded brightness control information and the light irradiation control. 2. The light distribution control system according to 2. The light distribution control system according to claim 3, wherein the control information transmission unit converts the brightness control information into an image format and compresses the converted brightness control information. The brightness control unit determines a plurality of target light irradiation states according to a plurality of types of driving environments, synthesizes the determined plurality of light irradiation states, and adjusts the brightness to the combined light irradiation states. The light distribution control system according to any one of claims 1 to 4, which generates control information. The light distribution according to any one of claims 1 to 5, wherein the control information transmitting unit calculates a difference between the previous brightness control information and the current brightness control information, and transmits the calculated difference. Control system. The number of light irradiation regions constituting the plurality of light irradiation regions is different from the number of light sources constituting the plurality of light sources.
The lighting control unit allocates one or more light irradiation regions to each light source, determines the overall brightness of the one or more light irradiation regions, and determines the overall brightness of the one or more light irradiation regions, and at the determined brightness, the one or more light irradiation regions. The light distribution control system according to any one of claims 1 to 6, wherein the light source assigned to the light source is turned on. The light distribution control system includes a communication device that communicates with an external device via an external network.
The lighting control unit allocates one or more light irradiation regions to one light source based on the headlight configuration parameters indicating the configurations of the plurality of light sources.
The light distribution control system according to claim 7, wherein the headlight configuration parameters are rewritten by the external device via the communication device.

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