JP2009230568A - Drunk state determining device, and drunk driving prevention device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drunk state determining device capable of performing drunk state determination at low cost and a drunk driving prevention device using the determination result. <P>SOLUTION: The drunk state determining device (10) is provided with an imaging means (20), a temperature adjusting means for adjusting temperature in a lens part (22) of the imaging means to prescribed temperature, and a determining means (40) for determining whether a person to be a determination target is in a drunk state on the basis of the degree of cloudiness of a picked-up image of the imaging means after a person to be a determination target blows breath on the lens part of the imaging means. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a drunk state determination device that determines whether a person is in a drunk state using a camera, and a drunk driving prevention device that performs control for suppressing drunk driving using the determination result.

  In recent years, from the viewpoint of safe driving, research on drunk driving prevention devices that determine whether a driver is in a drunk state and permit the vehicle to run only when it is determined that the driver is not in a drunk state has been promoted. ing.

  As a method for determining whether or not the driver is in a drunk state, for example, an inspection device having an exhalation breathing port is arranged near the driver's seat so that the driver breathes in when the vehicle starts. It is conceivable to make a determination by comparing the concentration of an indicator component such as alcohol or acetaldehyde contained in exhaled breath with a determination threshold value.

In addition, in light of the fact that there are people who are resistant to breathing by putting a mouth in the breath-inlet, research is also progressing on technology for determining alcohol, acetaldehyde, etc. contained in the air in the passenger compartment. It has been. According to such a technique, it is possible to perform determination and control for preventing drunk driving even while the vehicle is running. As an example of such a technique, an invention relating to a danger prevention device in which a sensor such as an anthracene sensor for detecting alcohol vapor is installed in the vicinity of a driver's seat is disclosed (for example, see Patent Document 1).
JP 2004-249847 A

  However, an increase in cost as an in-vehicle device is inevitable regardless of whether the above-described exhalation inlet is used or not. Accordingly, it is desirable to develop an apparatus that uses existing equipment to determine whether a person (especially a vehicle driver) is in a drinking state.

  This invention is for solving such a subject, and mainly provides the drunk state determination apparatus which can perform a drunk state determination cheaply, and the drunk driving prevention apparatus using the determination result. Objective.

In order to achieve the above object, the first aspect of the present invention provides:
Imaging means;
Temperature adjusting means for adjusting the temperature in the lens portion of the imaging means to a predetermined temperature;
Based on the degree of cloudiness in the captured image of the imaging means after the person to be judged blows on the lens part of the imaging means, it is determined whether or not the person to be judged is in a drinking state. A determination means;
It is a drinking state determination apparatus provided with.

  According to the first aspect of the present invention, the drinking level can be determined at low cost. Further, it is sanitary as compared with a device in which a mouth is attached to a blowing port and a breath is blown, and when it is mounted on a vehicle, the determination can be performed during traveling.

In the first aspect of the present invention,
The predetermined temperature is preferably a temperature between 78 degrees Celsius and 100 degrees Celsius.

In the first aspect of the present invention,
When the person to be judged is not in a drinking state, the person to be judged has a storage means for storing a captured image after blowing the lens part of the imaging means as a reference image,
The determination means includes a degree of cloudiness in the captured image of the imaging means after the person to be determined blows on the lens unit of the imaging means, and a degree of cloudiness in the reference image stored in the storage means And a means for determining whether or not the person to be determined is in a drinking state.

In the first aspect of the present invention,
It is preferable that the image pickup means is mounted on a vehicle and installed at a position where the driver's head can be imaged from the front.

According to a second aspect of the present invention, there is provided a drinking level determination apparatus according to the first aspect of the present invention mounted on a vehicle,
Drunk driving suppression control means for performing control for suppressing drunk driving using the determination result of the drinking level determination device;
A drunk driving prevention apparatus comprising:

  According to the second aspect of the present invention, drunk driving can be effectively prevented based on the determination result determined at low cost.

  ADVANTAGE OF THE INVENTION According to this invention, the drunk state determination apparatus which can perform a drunk state determination cheaply, and the drunk driving prevention apparatus using the determination result can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings.

  Hereinafter, a drunk state determination apparatus 10 according to an embodiment of the present invention and a drunk driving prevention apparatus 1 using the determination result will be described. The drinking level determination device 10 is a device that is mounted on a vehicle and determines whether or not the driver is in a drinking level. In addition, the application of the drinking level determination apparatus according to the present invention is not limited to an in-vehicle apparatus, and can be realized as, for example, an apparatus in which an additional function is added to a mobile phone or the like.

  FIG. 1 is a diagram illustrating an example of the overall configuration of a drinking level determination device 10 and a drunk driving prevention device 1. The drunk driving prevention device 1 includes a drunk state determination device 10 and a drunk driving suppression control ECU (Electronic Control Unit) 50.

  The drinking level determination device 10 includes a vehicle interior camera 20 and an image processing device 40 as main components.

  The vehicle interior camera 20 is disposed at an arbitrary position where the driver's head can be imaged from the front (for example, around the steering column or the rearview mirror), and images the driver's face. The vehicle interior camera 20 includes, for example, an imaging lens 22, an image sensor 24, an electronic control unit 26, and a temperature adjustment mechanism 30. In the following description, it is assumed that the vehicle interior camera 20 is a CCD camera.

  The image sensor 24 is, for example, an interline type image sensor. A photodiode, which is a light receiving element that performs photoelectric conversion, and a CCD corresponding thereto are arranged in a two-dimensional plane, and an analog is provided between the photodiode and the CCD. A transfer gate functioning as a switch is included. A microlens for condensing light is attached to the front side of each photodiode (on the imaging lens 22 side). Such a structure is merely schematically illustrated for the purpose of simply explaining the function of the image sensor 24, and any design change for improving functionality or the like is allowed. Further, not only the interline type image sensor but also a full frame transfer type or frame transfer type image sensor in which the CCD itself functions as a light receiving element may be used.

  The electronic control unit 26 is, for example, a microcomputer or an electronic circuit, and controls the opening / closing timing of the transfer gate of the image sensor 24 to control the shutter speed and imaging cycle (for example, several times per second) of the vehicle interior camera 20. 10 times). The electronic control unit 26 amplifies the data output from the output circuit of the image sensor 24 with a predetermined gain and outputs the data to the image processing device 40 as image data.

  Note that the above-described hardware configuration of the in-vehicle camera 20 can be shared with a camera used in a control system that detects a driver's drowsiness or aside and gives an alarm or the like. Therefore, when applied to a vehicle equipped with such a control system, the cost burden is greatly reduced.

  The temperature adjustment mechanism 30 is a mechanism for maintaining the temperature around the imaging lens 22 in the vehicle interior camera 20 at a predetermined temperature. Here, the predetermined temperature may be arbitrarily determined between 78 [° C.] and 100 [° C.], for example, may be set to about 80 [° C.]. Here, 78 [° C.] is the boiling point of ethyl alcohol (ethanol), and 100 [° C.] is the boiling point of water. Accordingly, the predetermined temperature is a temperature at which ethyl alcohol contained in the driver's breath is vaporized but moisture is not vaporized. The “temperature around the imaging lens 22 in the vehicle interior camera 20” may be “in the vehicle interior camera 20”. This is because the possibility of a particularly large temperature distribution occurring in the vehicle interior camera 20 is low.

  The temperature adjustment mechanism 30 includes, for example, an electric fan, a thermostat, and the like. In addition, when the imaging cycle of the vehicle interior camera 20 is determined in advance and the heat generation amount and the heat release amount in the steady state are known, the vehicle interior camera 20 may be configured by a simple vent or a heat insulating material. This is because it is sufficient that the imaging lens 22 is maintained at a predetermined temperature in a steady operation state.

  The image processing apparatus 40 is, for example, a computer unit in which a ROM (Read Only Memory), a RAM (Random Access Memory), and the like are connected to each other via a bus with a central processing unit (CPU) as a center. An HDD (Hard Disc Drive), a DVD (Digital Versatile Disk) drive, a CD (Compact Disc) drive, a storage device 42 such as a flash memory, an I / O port, a timer, a counter, and the like are provided. The ROM stores programs and data executed by the CPU. Further, it is assumed that a speaker 44 is connected to the image processing apparatus 40, and a program for functioning as a VUI (Voice User Interface) is stored in the ROM.

  The image processing device 40 determines whether or not the driver is in a drinking state based on the degree of cloudiness in the captured image of the vehicle interior camera 20 after the driver blows on the lens unit 22 of the vehicle interior camera 20. judge.

  More specifically, when the driver is not in a drunk state, a captured image after the driver blows on the lens unit 22 of the vehicle interior camera 20 is stored in the storage device 42 in advance as a reference image. Is the degree of cloudiness in the image captured by the vehicle interior camera 20 after blowing on the lens unit 22 of the vehicle interior camera 20 (hereinafter simply referred to as “the degree of cloudiness this time”), and the degree of cloudiness in the reference image. To determine whether the driver is in a drinking state.

  Here, “the degree of cloudiness” is a value quantified by image analysis, and basically means a decrease in luminance difference (contrast) between each pixel and surrounding pixels. Specifically, the following processes may be appropriately selected or combined.

  (1) A vertical or horizontal scanning line is arbitrarily extracted from the image, and a luminance distribution analysis such as frequency analysis is performed on the scanning line to quantify a decrease in contrast. When performing frequency analysis, for example, when there are many low frequency components, it is determined that the degree of cloudiness is large.

  (2) When detecting feature points of a driver's face by template matching or AdaBoost (which is a pattern recognition learning method), if the degree of cloudiness is large when the detection reliability of each feature amount is uniformly low to decide. The detection of feature points in the image may be performed only for the determination of the drinking level, or may be performed as a process of detecting the driver's drowsiness or looking aside as a process different from the determination of the drinking level.

  (3) Further, the degree of cloudiness may be quantified by observing the values quantified by the processes (1) and (2) in time series.

  When the difference between the current cloudiness level and the cloudiness level in the reference image is equal to or greater than a predetermined value, it is determined that the driver is in a drinking state, and when the difference is less than the predetermined value, driving It is determined that the person is not in a drinking state.

  This determination method is based on the fact that the temperature around the imaging lens 22 is set to a predetermined temperature between the boiling point of ethyl alcohol and the boiling point of water. That is, when a driver who is not in a drunk state blows on the imaging lens 22, the liquid moisture contained in the driver's breath is not vaporized depending on the temperature of the imaging lens 22, causing the imaging lens 22 to become cloudy. On the other hand, when a driver in a drunk state blows on the imaging lens 22, the liquid state moisture contained in the driver's breath does not vaporize and causes clouding in the imaging lens 22, but ethyl alcohol vaporizes. Thus, the image pickup lens 22 is not fogged. For this reason, when the driver in the drunk state blows into the imaging lens 22, the degree of cloudiness is smaller than in the case of not in the drunk state. The presence of ethyl alcohol reduces the percentage of water in the driver's breath). FIG. 2 is a diagram schematically showing how the degree of cloudiness changes based on such a principle.

  With such a configuration and processing, the drinking level determination can be performed at low cost. Moreover, it is hygienic as compared with a device in which a mouth is attached to a blowing port and a breath is blown, and a determination can be made during traveling.

  The drunk driving suppression control ECU 50 is, for example, a computer having a hardware configuration similar to that of the image processing device 40, and the determination result of the drunk state determination device 10 determines that the driver is in the drunk state. In addition, various controls for suppressing drunk driving (hereinafter referred to as drunk driving suppression control) are performed. Specifically, the drunk driving suppression control outputs an instruction signal to the engine control computer so as to prohibit or forcibly stop the engine when the vehicle is stopped. Also, if the vehicle is running, the vehicle speed is restricted, the shift position is fixed or restricted (restricted to 1st speed or 2nd speed), etc., and when the vehicle speed falls below a certain speed, forced braking operation, fuel supply cut, etc. are performed. Stop the vehicle. The drunk driving suppression control ECU 50 and the image analysis device 40 may be the same hardware.

  Hereinafter, the operation when the drunk driving prevention apparatus 1 performs the drunk state determination and performs the drunk driving suppression control based on the determination result will be described. FIG. 3 is a flowchart showing a flow of characteristic processing executed by the drunk driving prevention apparatus 1 according to the present embodiment. This flow is executed, for example, at the start of the vehicle system and at a desired timing thereafter.

  First, the image analysis device 40 calls the driver to blow on the vehicle interior camera 20 using the speaker 44 (S100). Such processing may be performed by the drunk driving suppression control ECU 50. Moreover, you may recognize that the image analysis apparatus 40 blew by image analysis, and the call which concerns in this case becomes unnecessary.

  And it waits until the fixed time required for the lens 22 to become cloudy by breathing passes (S102).

  When a certain time has elapsed, a captured image captured at that time is extracted (S104), and image analysis is performed to calculate the degree of cloudiness this time (S106).

  Then, it is determined whether or not the difference between the current cloudiness level and the cloudiness level in the reference image stored in the storage device 42 is greater than or equal to a predetermined value (S108). If the difference in cloudiness is equal to or greater than a predetermined value, it is determined that the driver is in a drunk state (S110), and a signal indicating that is output to the drunk driving suppression control ECU 50. In response to this, the drunk driving suppression control ECU 50 executes drunk driving suppression control (S112), and the drunk driving prevention apparatus 1 ends one routine of this flow. When the vehicle system is started in a state where drunk driving suppression control is executed, that is, when the vehicle is configured not to permit driving unless it is determined that the driver is not in a drunk state when riding In other words, the process of S112 at the time of starting the system is “continue” the drunk driving suppression control.

  On the other hand, if the difference in cloudiness is less than the predetermined value, it is determined that the driver is not in a drunk state (S114), and a signal indicating that is output to the drunk driving suppression control ECU 50. The drunk driving suppression control ECU 50 does not execute the drunk driving suppression control (cancel this if it is already executed; S116), and the drunk driving prevention device 1 ends one routine of this flow.

  According to the drinking level determination device 10 of the present embodiment, the drinking level determination can be performed at low cost. Moreover, according to the drunk driving prevention apparatus 1 of a present Example, drunk driving can be prevented effectively based on the determination result determined cheaply.

  The best mode for carrying out the present invention has been described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. And substitutions can be added.

  For example, when the driver is not in a drinking state, the captured image after the driver blows on the lens unit 22 of the in-vehicle camera 20 is not stored in the storage device 42 in advance as a reference image, and the standard cloudiness level is not stored. It may be stored in advance as a numerical value, and the drinking level determination may be performed by comparing this numerical value with “the degree of cloudiness this time”.

  The present invention can be used in the automobile manufacturing industry, the automobile parts manufacturing industry, and the like.

It is a figure which shows an example of the whole structure of the drunk state determination apparatus 10 which concerns on a present Example, and the drunk driving prevention apparatus 1 using the determination result. It is a figure which shows a mode that the degree of cloudiness changes typically. It is a flowchart which shows the flow of the characteristic process which the drunk driving prevention apparatus 1 which concerns on a present Example performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drunk driving prevention apparatus 10 Drunk state determination apparatus 20 Car interior camera 22 Imaging lens 24 Image sensor 26 Electronic control part 30 Temperature control mechanism 40 Image processing apparatus 42 Memory | storage device 44 Speaker 50 ECU for drunk driving suppression control

Claims (5)

Imaging means;
Temperature adjusting means for adjusting the temperature in the lens portion of the imaging means to a predetermined temperature;
Based on the degree of cloudiness in the captured image of the imaging means after the person to be judged blows on the lens part of the imaging means, it is determined whether or not the person to be judged is in a drinking state. A determination means;
A drinking state determination device comprising: The predetermined temperature is a temperature between 78 degrees Celsius and 100 degrees Celsius.
The drinking level determination apparatus according to claim 1. When the person to be judged is not in a drinking state, the person to be judged has a storage means for storing a captured image after blowing the lens part of the imaging means as a reference image,
The determination means includes a degree of cloudiness in the captured image of the imaging means after the person to be determined blows on the lens unit of the imaging means, and a degree of cloudiness in the reference image stored in the storage means The drinking level determination device according to claim 1, which is a means for determining whether or not the person to be determined is in a drinking state. Mounted on the vehicle, the imaging means is installed at a position where the driver's head can be imaged from the front;
The drinking level determination apparatus according to any one of claims 1 to 3. The drinking level determination device according to claim 4,
Drunk driving suppression control means for performing control for suppressing drunk driving using the determination result of the drinking level determination device;
A drunk driving prevention device comprising: