JP2003127759A - Light distribution control system of lighting fixture for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change light distribution for a light distribution control system of a lighting fixture for a vehicle without giving a driver a sense of incongruity even when the vehicle is accelerating and decelerating. SOLUTION: A main control circuit of the light distribution control system of the lighting fixture for the vehicle calculates acceleration of a vehicle at a step 112 while the vehicle is running and controls light distribution by selecting either mode based on the calculated acceleration. When the vehicle is running at a constant speed, light distribution control by a normal mode is practiced at a step 116. When the vehicle is accelerating, light distribution control by an acceleration road mode is practiced at a step 118 and light distribution of a group of lamps is switched at timing which is earlier than that of practice of light distribution control by a normal mode. When the vehicle is decelerating, light distribution control by a deceleration mode is practiced at a step 120 and light distribution of a group of lamps is switched at timing which is later than that of practice of light distribution control by a normal mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light distribution control system for controlling light distribution of vehicular lamps such as headlights.

[0002]

2. Description of the Related Art Conventionally, as a system of this type, as shown in Japanese Patent Publication No. 7-71908, a map database storing a road map and a current position of a vehicle are stored in the map database. Vehicle position specifying means for specifying on the road, and a vehicle lamp attached to the front part of the vehicle according to the current position of the vehicle on the road stored in the map database specified by the vehicle position specifying means With a light distribution control means for controlling the light distribution of the vehicle, by controlling the irradiation area of the lamp according to the traveling direction of the vehicle or the traveling environment while the vehicle is traveling, always try to secure a good visual field for the driver. It is well known that

[0003]

However, in the above conventional system, the light distribution control means distributes light when changing the light distribution of the vehicular lamp according to the current position of the vehicle specified by the vehicle position specifying means. Light switching was always performed at a uniform timing regardless of the vehicle acceleration. Therefore,
If the light distribution is changed while the vehicle is accelerating or decelerating, the driver feels that the light distribution switching is too slow while the vehicle is accelerating, and the light distribution switching is too early while the vehicle is decelerating. I felt that something was wrong with each of them.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light distribution system for a vehicular lamp which can change the light distribution without giving a feeling of discomfort to a driver even when the vehicle is accelerating or decelerating. It is in.

A structural feature of the present invention is that in a light distribution control system for a vehicle lighting device, which comprises the map database, a vehicle position specifying means, and a light distribution control means, an acceleration detecting means for detecting a vehicle acceleration is provided. When changing the light distribution of the vehicular lamp, the light distribution control means adjusts the timing of switching the light distribution according to the acceleration of the vehicle detected by the acceleration detection means, and when the vehicle is accelerating, the light distribution control means is adjusted. It is configured such that the timing to start switching the light is advanced and the timing to start switching the light distribution is delayed when the vehicle is decelerating. According to this, even when the light distribution is changed during acceleration or deceleration of the vehicle, the switching timing of the light distribution is adjusted according to the acceleration of the vehicle, which gives the driver a feeling of strangeness. Is avoided.

One of the control during acceleration and the control during deceleration may be omitted and only one of them may be adopted. This also makes it possible to expect the effects of the present invention.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. The light distribution control system for a vehicular lamp shown in FIG. 1 controls the light distribution of a lamp group 10 by a light distribution control circuit 20, and also partially serves as a navigation (route guidance) system 30 mounted on a vehicle. Is configured.

The lamp group 10 is composed of a plurality of lamps such as head lamps, fog lamps, and corner lamps attached to the front of the vehicle, and illuminates the vehicle from the front to the side. The entire light distribution can be changed by changing the irradiation range, the light amount, or the like. The light distribution control circuit 20 controls the light distribution of the lamp group 10 in accordance with the instruction signal output from the navigation control circuit 31 of the navigation system 30.

The navigation system 30 includes an input / output unit 32, a map database 33, a GPS receiver 34, a direction sensor 35, which are connected to the main control circuit 31, respectively.
A vehicle speed sensor 36 and a VICS receiver 37 are provided. The input / output unit 32 is operated by the driver at the time of designating a destination, and outputs necessary guidance information to the driver by screen display or voice. The map database 33 stores the position and shape of the road by a plurality of nodes (nodes) and a plurality of links (line segments) connecting the respective nodes.

The GPS (Global Positioning System) receiver 34 receives a GPS signal transmitted from a GPS satellite and representing the current position of the vehicle. Direction sensor 3
5 detects the direction in which the vehicle is heading. The vehicle speed sensor 36 detects the speed of the vehicle. V
ICS (Vehicle Information & Communication Syste)
m) The receiver 37 receives a VICS signal representing road traffic information such as the traffic volume of the traveling path of the vehicle, by road-to-vehicle communication using FM multiplexing, radio wave beacons, optical beacons and the like.

The main control circuit 31 includes an instruction operation by the driver in the input / output unit 32, map data stored in the map database 33, GPS and VICS receiver 3.
A program corresponding to the flowchart shown in FIG. 2 is executed based on the GPS and VICS signals received by the sensors 4 and 37 and the detection by the sensors 35 and 36 to perform the processing as the navigation system and the distribution of the lamp group 10. The light is determined and an instruction signal is output to the light distribution control circuit 20. In addition, the main control circuit 31
A lighting switch 41 for instructing lighting of the lamp group 10 is also connected to.

Next, the operation of the light distribution control system configured as described above will be described with reference to the flowchart of FIG.
First, when an ignition switch (not shown) of a vehicle is turned on, the main control circuit 31 causes the step 100
The execution of the program is started in step 102 and thereafter step 102
The cyclic processing consisting of 120 is repeatedly executed.

The main control circuit 31 starts with step 1
At 02, a signal indicating the driver's instruction operation, map data, GPS and VICS signals, and each detection signal are input. Then, in step 104, map matching processing is executed. What is map matching processing?
The current position of the vehicle is calculated based on the input GPS signal and each detection signal, and the calculated current position is matched with the map data, so that the current position of the vehicle on any road represented by the map data. Is a process for specifying. Note that the same process is repeatedly executed during the above circulation process without stopping the progress of the program, and the calculated current position of the vehicle does not match the map data, and the vehicle on the road represented by the map data is Even if the current position cannot be specified, the program is allowed to proceed to the next step 106 and subsequent steps without completing the same processing.

In step 106, the current position of the vehicle specified by the map matching process, the signal representing the input operation of the driver, the map data,
Based on the VICS signal and the VICS signal, a process (navigation process) as a navigation system is executed such as calculating a route to a destination of the vehicle and guiding the driver.

In step 108, it is determined whether or not the map matching process is completed. At this time,
When the map matching process is incomplete, that is, when the calculated current position of the vehicle does not match the map data and the current position of the vehicle cannot be specified on the road represented by the map data, the main control circuit 31 , "NO", the program is returned to step 102. On the other hand, if the map matching process is completed at this time,
The main control circuit 31 advances the program to step 110 and subsequent steps based on the determination of "YES".

In step 110, it is determined whether the lighting switch 41 is in the on state. At this time, if the driver has not instructed the lighting of the lamp group 10 and the lighting switch 41 is in the off state, the main control circuit 3
1 determines "NO" and returns the program to step 102. On the other hand, if the driver has instructed the lighting of the lamp group 10 at this time and the lighting switch 41 is in the ON state, the main control circuit 31 makes a “YES” determination and advances the program to step 112 and subsequent steps to distribute the light. Start processing for control.

In step 112, the vehicle speed sensor 3
The vehicle speed detected by 6 is differentiated to calculate the vehicle acceleration. In step 114, based on the calculated acceleration, it is determined whether the vehicle is traveling at a substantially constant speed without acceleration / deceleration, the vehicle is accelerating, or the vehicle is decelerating. Branch the program.

When it is determined that the vehicle is traveling at a constant speed, the main control circuit 31 executes the light distribution control in the normal mode in step 116. This process is specifically executed as follows.

First, based on the current position of the vehicle specified by the map matching processing in step 104 and the vehicle speed detected by the vehicle speed sensor 36, as shown in FIG. 3 (a), it is stored in the map database 33. The predicted position of the vehicle on the existing road after a predetermined time (for example, 2.5 seconds) is specified. Then, while the predicted position is updated as the vehicle progresses, it is repeatedly determined whether or not the predicted position has reached a point that requires light distribution change control. Here, the point where the change control of the light distribution is required is, for example, a point where the road shape changes such as a point approaching a curve from a straight road or a point exiting from a curve to a straight road, an intersection, or the map database 33 in advance. The driving area of the vehicle defined on the map data of
Urban areas, suburbs, highways, etc.) are points where switching occurs.

However, this processing is repeatedly executed during the circulation processing consisting of the above steps 102 to 120 without stopping the progress of the program. When the newly specified predicted position has not reached the above-mentioned light distribution change control point, the program is temporarily returned to step 102 without executing the light distribution change control, and the same step 116 is executed next time. At some point, the predicted position is updated and the same determination is performed again. By repeating this,
The main control circuit 31 waits for the predicted position of the vehicle to reach the light distribution change required control point.

During the circulation processing, when the predicted position reaches the light distribution change required control point, the main control circuit 31 determines an appropriate light distribution to the same point and sends a signal instructing the determined light distribution. Output to the light distribution control circuit 20. Accordingly
The light distribution control circuit 20 controls the lamp group 10 to switch the light distribution.

On the other hand, when it is determined in step 114 that the vehicle is accelerating, the main control circuit 31 executes light distribution control in the accelerating mode in step 118. Also in the same mode, the main control circuit 31 specifies the predicted position, determines the light distribution when the predicted position reaches the light distribution change control point required, and outputs the light distribution instruction signal. In this case, as shown in FIG. 3B, the predicted position is compared with the light distribution control in the normal mode in step 116, and the position is far from the current position of the vehicle, that is, the vehicle is slow (for example, 3). 5 seconds later) Specify the position to reach. Therefore, when the light distribution control is performed in the accelerating mode, the light distribution of the lamp group 10 is switched at an earlier timing than when the light distribution control is performed in the normal mode.

On the other hand, when it is determined in step 114 that the vehicle is decelerating, the main control circuit 31 executes light distribution control in the decelerating mode in step 120. Also in the same mode, the main control circuit 31 specifies the predicted position, determines the light distribution when the predicted position reaches the light distribution change control point required, and outputs the light distribution instruction signal. In this case, as shown in FIG. 3C, the predicted position is compared with the light distribution control in the normal mode in step 116, and the position is closer to the current position of the vehicle, that is, the vehicle is faster (for example, 5 seconds later) Specify the position to reach. Therefore, when the light distribution control in the decelerating mode is executed, the light distribution of the lamp group 10 is switched at a later timing than when the light distribution control in the normal mode is executed.

In each of the above cases, the light distribution is switched gradually and continuously. For example, when the optical axis α of the lamp group 10 is swung to the left and right, the light distribution is switched by gradually increasing the swing angle α of the optical axis after the switching start timing of each light distribution (see FIG. 3). ).

As described above, in the above embodiment,
Depending on the acceleration of the vehicle calculated in step 112, the light distribution control process in each of steps 116 to 120 is selected and the light distribution switching timing is adjusted. Therefore, even when the light distribution is changed while the vehicle is accelerating or decelerating, it is possible to prevent the driver from feeling uncomfortable.

In the above embodiment, the acceleration of the vehicle is calculated by differentiating the vehicle speed detected by the vehicle speed sensor 36, but instead of this, FIG.
As indicated by the chain double-dashed line, an acceleration sensor 42 that directly detects the acceleration of the vehicle may be separately provided, and the detection value of the acceleration sensor 42 may be used for the determination in step 112.

Further, in the above embodiment, the three types of light distribution control of the normal mode, the accelerating mode and the decelerating mode are selectively executed based on the acceleration of the vehicle. The mode classification may be further subdivided according to the magnitude of acceleration. Also, by directly determining the predicted position from the magnitude of acceleration,
The timing of switching the light distribution may be arbitrarily adjusted according to the magnitude of the acceleration. Further, one of the accelerating mode and the decelerating mode may be omitted, and only one of the accelerating control and the decelerating control may be adopted. This also makes it possible to expect the effects of the present invention.

[Brief description of drawings]

FIG. 1 is an overall schematic view of a light distribution control system for a vehicle lamp according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a program executed by a main control circuit of FIG.

FIG. 3A shows a switching start timing of light distribution during constant speed traveling of the vehicle, FIG. 3B shows a switching start timing of light distribution during acceleration of the vehicle, and FIG. 3C is during deceleration of the vehicle. FIG. 6 is an explanatory diagram showing a switching start timing of light distribution in FIG.

[Explanation of symbols]

10 ... Lamp group, 20 ... Light distribution control circuit, 30 ... Navigation system, 31 ... Main control circuit, 33 ... Map database, 42 ... Acceleration sensor.

Continued front page    (72) Inventor Satoru Tanaka             18 Aishi, 6 Harayama, Okamachi, Okazaki City, Aichi Prefecture             N AW Co., Ltd. (72) Inventor Toshiaki Niwa             18 Aishi, 6 Harayama, Okamachi, Okazaki City, Aichi Prefecture             N AW Co., Ltd. (72) Inventor Masako Kobayashi             500 Kitawaki, Shimizu City, Shizuoka Prefecture Koito Co., Ltd.             Factory Shizuoka factory F term (reference) 3K039 AA08 CC01 DC02 GA02 JA03                       MB10

Claims (3)

[Claims] 1. A map database storing a road map, a vehicle position specifying means for specifying a current position of a vehicle on a road stored in the map database, and the map specified by the vehicle position specifying means. A light distribution control system for a vehicle lamp, comprising: a light distribution control means for controlling light distribution of a lamp attached to a front portion of the vehicle according to a current position of the vehicle on a road stored in a database; Acceleration detection means for detecting the acceleration of the traveling path of the vehicle is provided, and when the light distribution control means changes the light distribution of the vehicle lamp, the timing of switching the light distribution is detected by the acceleration detection means. Adjust according to the acceleration, and if the vehicle is accelerating, advance the timing to start switching the light distribution, and if the vehicle is decelerating, switch the light distribution. A light distribution control system for a vehicular lamp, which is characterized by delaying the timing of lighting. 2. A map database storing a road map, a vehicle position specifying means for specifying the current position of the vehicle on the road stored in the map database, and the map specified by the vehicle position specifying means. A light distribution control system for a vehicle lamp, comprising: a light distribution control means for controlling light distribution of a lamp attached to a front portion of the vehicle according to a current position of the vehicle on a road stored in a database; Acceleration detection means for detecting the acceleration of the traveling path of the vehicle is provided, and when the light distribution control means changes the light distribution of the vehicle lamp, the timing of switching the light distribution is detected by the acceleration detection means. When the vehicle is accelerating, the timing for starting the switching of the light distribution is advanced as compared with that during constant speed traveling. Light control system. 3. A map database storing a road map, a vehicle position specifying means for specifying the current position of a vehicle on the road stored in the map database, and the map specified by the vehicle position specifying means. A light distribution control system for a vehicle lamp, comprising: a light distribution control means for controlling light distribution of a lamp attached to a front portion of the vehicle according to a current position of the vehicle on a road stored in a database; Acceleration detection means for detecting the acceleration of the traveling path of the vehicle is provided, and when the light distribution control means changes the light distribution of the vehicle lamp, the timing of switching the light distribution is detected by the acceleration detection means. Adjusting according to acceleration, and when the vehicle is decelerating, the timing of starting the switching of the light distribution is delayed as compared with that during constant speed traveling. Light distribution control system.