JP2011008457A - Automobile driver doze prevention device - Google Patents
Automobile driver doze prevention device Download PDFInfo
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本発明は、車両運転手の居眠り状態を監視、およびその防止を行う装置に関するものである。 The present invention monitors the dozing state of the vehicle driver, and to a device for performing the prevention.
交通事故件数の構成率を法令違反別に死亡事故と比較すると漫然運転（居眠り運転）は１５パーセント以上と他の法令違反と比べて高いことが上げられる（非特許文献１）。
そのため、運転者の生体情報を取得し、眠気が発生しているかを判定し、眠気が発生していると判断したときには運転者へ眠気防止用の刺激を与えるシステムなどが考案されている（たとえは、特許文献１、特許文献２など）。
また、眠気の発生を判定する技術として例えば特許文献３には、心電図、脈波、呼吸、脳波などの生体情報から測定した生体信号の周波数分析やビート間隔の揺らぎなどを判断し、自律神経の状態を分析する方法が提案されている。
Comparing the composition ratio of the number of traffic accidents with fatal accidents by violation of laws and regulations, it can be said that random driving (sleeping driving) is 15% or more, which is higher than other violations of laws and regulations (Non-Patent Document 1).
For this reason, a system has been devised that acquires biometric information of the driver, determines whether sleepiness is occurring, and gives a stimulus to the driver to prevent sleepiness when it is determined that sleepiness has occurred (for example, (Patent Document 1, Patent Document 2, etc.).
As a technique for determining the occurrence of drowsiness, for example, in Patent Document 3, frequency analysis of biological signals measured from biological information such as electrocardiograms, pulse waves, respirations, and brain waves, and fluctuations in beat intervals are determined. A method of analyzing the state has been proposed.
一方、漫然運転が多く発生してしまう状況というのは、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を運転しているときなどが挙げられる。
そのような場所での運転では、比較的一定の速度で走行し、ハンドル操作、シフトチェンジ、ブレーキ操作、ウインカー操作、アクセル操作などの運転操作量が市街地などを走行しているときに比べ少なくなっている場合である。さらに、そのような場所の路面状態は比較的均一に舗装されており、走行中は単調な振動が続く状況となる。
On the other hand, the situation where a lot of random driving occurs is when driving in a place where the distance between traffic lights is long, such as suburban roads and expressways, where straight or gentle curves continue. Can be mentioned.
When driving in such a place, the vehicle travels at a relatively constant speed, and the amount of driving operation such as steering wheel operation, shift change, braking operation, turn signal operation, and accelerator operation is less than when driving in urban areas. It is the case. Furthermore, the road surface condition of such a place is paved relatively uniformly, and a monotonous vibration continues during traveling.
生体情報は常に安定した信号となっている訳ではなく、信号自身が大きく揺らぐ場合や、また、被測定者の感情や健康状態によって大きく変化することが知られていることから、眠気の判定を確実に実行するのは困難であった。 Biological information is not always a stable signal, and it is known that the signal itself fluctuates greatly, and it is known that it changes greatly depending on the emotion and health status of the subject. It was difficult to do reliably.
また、移動状態の車両の中で眠気の判定をする際には、被測定者は車両の原動機などによる振動や車両の加速減速、カーブ、右左折、車線変更などによるゆれや運転手の動作によって雑音が混入し、間違えた判定結果になることがある。そのため、一定の条件で生体信号を判定しても、被測定者の状態とは異なる結果を検出する可能性がある。
このように不安定な判定条件の下で自動車へ実装した場合、不用意に運転者に注意喚起与えてしまうことになる恐れがある。これにより、かえって運転者の運転集中を阻害してしまい、ひいては運転誤操作を誘引し、運転の妨げとなる可能性がある。
本願発明の目的は、運転手の生体情報から眠気を検知し、注意喚起を行うシステムにおいて、眠気を感じている状態か否かを生体情報及び車体の状況ないし車体周囲の状況から総合的に判定し、運転者にとって不用意な注意喚起を行わないように制御可能な居眠り運転防止装置を提供することにある。
In addition, when determining sleepiness in a moving vehicle, the person being measured is subject to vibrations caused by the motor of the vehicle, acceleration / deceleration of the vehicle, curves, right / left turns, lane changes, etc. Noise may be mixed, resulting in a wrong determination result. Therefore, even if the biological signal is determined under a certain condition, a result different from the state of the measurement subject may be detected.
When mounted on an automobile under such unstable determination conditions, the driver may be inadvertently alerted. As a result, the driver's concentration of driving is hindered, which may lead to erroneous driving operation and hinder driving.
An object of the present invention is to comprehensively determine whether or not the person feels drowsiness from the biological information and the situation of the vehicle body or the situation around the vehicle body in a system for detecting drowsiness from the driver's biological information and calling attention. The object is to provide a drowsiness prevention device that can be controlled so as not to alert the driver carelessly.
上記課題を解決するための居眠り運転防止装置の態様として、ハンドルに運転者からの情報を検知するための複数のセンサーから構成される運転者状態検知手段を有し、車両の走行状態を検知するための複数のセンサーから構成される車輌状態検知手段を車輌内部に備え、前記車輌状態検知手段には自動車用衛星航行システムを含み、前記運転者状態検知手段からの検知情報に基づいて、運転者の眠気状態を判定する情報処理装置を備え、当該情報処理装置は、前記判定の結果、眠気が発生していると判定された場合に、前記車輌状態検知手段からの情報に応じて運転者に対して警告するか否かを判定することを特徴とする。 As an aspect of the drowsiness prevention device for solving the above-mentioned problem, the steering wheel has a driver state detecting means including a plurality of sensors for detecting information from the driver, and detects the driving state of the vehicle. Vehicle state detection means comprising a plurality of sensors for the vehicle, the vehicle state detection means includes a satellite navigation system for automobiles, and based on detection information from the driver state detection means, the driver An information processing device for determining the sleepiness state of the vehicle, and when the information processing device determines that drowsiness is occurring as a result of the determination, the information processing device informs the driver according to information from the vehicle state detection means. It is characterized by determining whether or not to warn.
本発明により、市街地など走行しており運転操作に集中しているときは注意喚起を発生させず、運転者への吃驚を与えないと共に、逆に眠気を生じやすい郊外の道路、高速道路を走行中では生体情報は安定に計測され、その情報分析も市街地走行時の情報分析よりも高い精度で眠気検知できる。そのため郊外の道路、高速道路での漫然運転が減り、交通事後の減少が期待される。 According to the present invention, when driving in an urban area and concentrating on driving operation, the driver is not alerted, does not surprise the driver, and conversely travels on a suburban road or highway where sleepiness is likely to occur. Among them, biometric information is stably measured, and the information analysis can detect drowsiness with higher accuracy than the information analysis during urban driving. As a result, there will be less driving on suburban roads and expressways, and a reduction after the traffic is expected.
図１は自動車運転席における運転手が操作する機器および居眠り防止装置の構成要素を示す。車両運転中は緊握センサー１９、加速度センサー３、振動センサー４、脈波センサー１４、心電センサー１８、自動車用衛星航行システム１６は常にセンシングしており、各センサーからの情報は情報処理装置５に入力されている。また、自動車用衛星航行システム１６からの現在の車両位置、車両速度、地図データも情報処理装置５に入力されている。図２は居眠り防止装置の構成要素である加速度センサー３、振動センサー４、情報処理装置５、脈波センサー１４、心電センサー１８、緊握センサー１９、音声発生装置１５、振動発生装置１３、表示装置１７、匂い発生装置２０、車内空調装置２１の接続を示している。 Figure 1 shows the components of the apparatus and doze prevention device driver to operate the motor vehicle driver's seat. While driving the vehicle, the grip sensor 19, the acceleration sensor 3, the vibration sensor 4, the pulse wave sensor 14, the electrocardiographic sensor 18, and the satellite navigation system 16 for the vehicle are always sensing, and information from each sensor is the information processing device 5. Has been entered. The current vehicle position, vehicle speed, and map data from the vehicle satellite navigation system 16 are also input to the information processing device 5. FIG. 2 shows an acceleration sensor 3, a vibration sensor 4, an information processing device 5, a pulse wave sensor 14, an electrocardiogram sensor 18, a grip sensor 19, a sound generation device 15, a vibration generation device 13, and a display, which are components of the dozing prevention device. 17, the odor generating apparatus 20 shows the connection of the vehicle air conditioner 21.
図３は居眠り防止装置の構成要素である加速度センサー３、振動センサー４、脈波センサー１４、心電センサー１８、音声発生装置１５、振動発生装置１３、表示装置１７、緊握センサー１９が自動車運転席内におけるおおよその配置を示す図で、後背斜視図である。 FIG. 3 shows an acceleration sensor 3, a vibration sensor 4, a pulse wave sensor 14, an electrocardiogram sensor 18, an audio generation device 15, a vibration generation device 13, a display device 17, and a grip sensor 19 which are components of the dozing prevention device. a diagram showing the approximate placement in the seat, a Spoons perspective view.
車輌走行中は図４に示す流れ図に従って眠気検出を行い、運転手が眠気を生じていると判定された場合に場合に注意喚起を与える。
図４の流れ図は、眠気が発生しやすい場所を走行しているかを、緊握センサー１９、加速度センサー３、振動センサー４、等のセンサーからの検出波形の経時変化を情報処理装置５において監視し、また、自動車用衛星航行システム１６による地理的情報を用いて、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いているような単調な道路を走行しているかどうかを情報処理装置５において判定したり、ブレーキ頻度をカウントしておくことで、交通信号機の間隔が長いような場所を走行しているかを情報処理装置５において判定する。このとき、地理的情報については、予め情報処理装置５内に記憶される距離基準等に基づいて判定する。
While the vehicle is running, drowsiness detection is performed according to the flowchart shown in FIG. 4, and a warning is given when it is determined that the driver is drowsy.
In the flowchart of FIG. 4, the information processing device 5 monitors changes over time in detection waveforms from sensors such as the grip sensor 19, the acceleration sensor 3, and the vibration sensor 4 to determine whether the vehicle is traveling in a place where sleepiness is likely to occur. In addition, the information processing apparatus 5 determines whether or not the vehicle travels on a monotonous road such as a suburban road or a highway that continues with a straight line or a gentle curve, using geographical information obtained by the vehicle satellite navigation system 16. In the information processing device 5, it is determined whether the vehicle is traveling in a place where the traffic signal interval is long. At this time, the geographic information is determined based on a distance reference stored in the information processing apparatus 5 in advance.
判定方法の具体例としては、緊握センサー１９ではハンドルを握っている場所の変化が所定時間(例えば１〜３分以上)変化がない場合、眠気を帯びやすい所を走行していると判定する。
加速度センサー３では加速度の変化からほぼ直線道路を所定時間(例えば１〜３分)走行しているかを判定する。
また、加速度センサー３では一定速度の走行が１〜３分走行しているかを合わせて判定するようにしても良い。
振動発生装置１３では、あらかじめ直線が続く高速道路などにおける振動の周波数スペクトルを計測して情報処理装置５に記憶しておき、現在走行中の振動スペクトルと波形比較し、同じ振動スペクトルが所定時間(例えば１〜３分)続いているかを判定する。
自動車用衛星航行システム１６では車輌の軌跡情報を記録しておき、ほぼ直線道路を所定時間(例えば１〜３分)走行しているかを判定する。
また、自動車用衛星航行システム１６では地図情報と車輌速度を元に、ほぼ直線道路を１〜３分走行しているかを判定するようにすることも可能である。
As a specific example of the determination method, it is determined that the grip sensor 19 is traveling in a place where sleepiness is likely to occur when there is no change in the place where the handle is held for a predetermined time (for example, 1 to 3 minutes or more). .
The acceleration sensor 3 determines whether the vehicle is traveling on a straight road for a predetermined time (for example, 1 to 3 minutes) from the change in acceleration.
Further, the acceleration sensor 3 may determine whether traveling at a constant speed is traveling for 1 to 3 minutes.
The vibration generator 13 measures in advance the frequency spectrum of vibration on a highway or the like where a straight line continues and stores it in the information processing device 5, compares the waveform with the vibration spectrum currently being traveled, and the same vibration spectrum is obtained for a predetermined time ( (For example, 1 to 3 minutes) It is determined whether it continues.
The vehicle satellite navigation system 16 records vehicle trajectory information, and determines whether the vehicle is traveling on a substantially straight road for a predetermined time (for example, 1 to 3 minutes).
Further, in the vehicle satellite navigation system 16, it is possible to determine whether or not the vehicle is traveling on a substantially straight road for 1 to 3 minutes based on the map information and the vehicle speed.
これら緊握センサー１９、加速度センサー３、振動センサー４、自動車用衛星航行システム１６は単独、または複数の組み合わせにより構成するとこができ、各種検出器からの判定は、それぞれ単独により、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定する場合と複数の組み合わせにより郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定する場合がある。
これらの組合せ条件や、情報処理装置５に予め設けられる判定閾値等は図示しない入力装置によって直接入力することも可能であり、予め記憶するようにしても良い。
The grip sensor 19, the acceleration sensor 3, the vibration sensor 4, and the vehicle satellite navigation system 16 can be configured singly or in combination, and determinations from various detectors can be made independently by suburban roads, A straight line or a gentle curve such as a suburban road or a highway by a combination of a case where it is judged that the vehicle is traveling in a place where a straight line or a gentle curve such as an expressway continues and the interval between traffic lights is long It may be determined that the vehicle is traveling in a place where the traffic signal interval is long.
These combination conditions, a determination threshold value provided in advance in the information processing apparatus 5 can be directly input by an input device (not shown), and may be stored in advance.
生体情報である脈波センサー１４、心電センサー１８からの信号は生体に装着しておくことで、常に計測することが可能である。脈波間隔、心電波形が覚醒時、たとえば市街地走行時の脈波、心電間隔と比べ長いと検知した場合、もしくは、脈波、心電間隔の揺らぎの周波数分析を行い、大よそ0.15〜0.4(Hz)の周波数帯域の成分が覚醒時に比べ増加していると検地した場合、もしくは、共に検知した場合、運転者に眠気が発生しているとして判定する。 Signals from the pulse wave sensor 14 and the electrocardiographic sensor 18 which are biological information can be always measured by being attached to the living body. When the pulse wave interval and ECG waveform are awake, for example, when it is detected that it is longer than the pulse wave and ECG interval when driving in the city, or the frequency analysis of fluctuations of the pulse wave and ECG interval is performed. If it is detected that the components in the frequency band of 0.4 (Hz) are increased compared to when awake, or if both are detected, it is determined that the driver is drowsy.
運転者に眠気が発生しているとして判定され、かつ郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定された場合、居眠り防止装置は音声発生装置１５による音声発生、振動発生装置１３による振動発生、表示装置１７による表示警告、匂い発生装置２０による香り発生、車内空調装置２１による風発生のいずれか、またはそれらを複合して実行し運転者に注意喚起を行う。
また、車輌の走行状態に応じて注意喚起をするための方法を変えるようにしても良い。
It was determined that the driver was drowsy, and it was determined that he was driving in a place where the traffic signal was long, such as a suburban road or a highway, followed by a straight or gentle curve. In this case, the snoozing prevention device is any one of sound generation by the sound generation device 15, vibration generation by the vibration generation device 13, display warning by the display device 17, scent generation by the odor generation device 20, wind generation by the vehicle air conditioner 21, or those Is executed in combination to alert the driver.
Moreover, you may make it change the method for alerting according to the driving | running | working state of a vehicle.
例えば、車輌振動が多く検出される場合に振動を発生させたとしても、運転者が気づかない場合もある。また、振動を伴う場合には車輌内部において振動に伴う騒音が発生する場合も考えられる。この場合には、例えば香りを発生させたり、表示画面上に警告表示をすると効果的である。 For example, even when a lot of vehicle vibration is detected, even if the vibration is generated, the driver may not notice. Moreover, it is conceivable that the noise caused by the vibration inside the vehicle generated when accompanied by vibrations. In this case, for example or to generate fragrance, it is effective to a warning display on the display screen.
その他、運転している地理的状況、センシングの結果に応じて警告方法を変えることがより効果的である。この場合、情報処理装置５において、センシング条件、地理的条件に所定基準を設けておき、夫々に対応する警告形態を記憶させるようにすることが肝要である。 Other geographic situation you are driving, it is more effective to change the warning method according to the result of the sensing. In this case, it is important for the information processing apparatus 5 to set predetermined criteria for the sensing condition and the geographical condition and to store the corresponding warning form.
図５に車輌の走行場所を判断し、その後、生体情報を計測し眠気を判断する流れ図を示す。図５では、まず、眠気が発生しやすい場所を走行しているかを、緊握センサー１９、加速度センサー３、振動センサー４、自動車用衛星航行システム１６によって、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行しているかを判定し、その後、生体情報である脈波センサー１４、心電センサー１８を用いて生体情報を計測し、脈波間隔、心電波形が覚醒時、たとえば市街地走行時の脈波、心電間隔と比べ長いと検知した場合、もしくは、脈波、心電間隔の揺らぎの周波数分析を行い、大よそ0.15〜0.4(Hz)の周波数帯域の成分が覚醒時に比べ増加していると検地した場合、もしくは、共に検知した場合、運転者に眠気が発生しているとして判定する。 Determining the travel location of the vehicle in FIG. 5, then, shows a flow diagram for determining a drowsiness measure the biological information. In FIG. 5, first, whether the vehicle is traveling in a place where sleepiness is likely to occur is determined by a straight line or a highway such as a suburban road or a highway by the grip sensor 19, the acceleration sensor 3, the vibration sensor 4, and the automobile satellite navigation system 16. It is determined whether the vehicle is traveling in a place where a gentle curve continues and the traffic signal interval is long, and then the biological information is measured using the pulse wave sensor 14 and the electrocardiographic sensor 18 which are biological information, When the pulse wave interval and ECG waveform are awake, for example, when it is detected that it is longer than the pulse wave and ECG interval when driving in the city, or the frequency analysis of fluctuations of the pulse wave and ECG interval is performed. If it is detected that the components in the frequency band of 0.4 (Hz) are increased compared to when awake, or if both are detected, it is determined that the driver is drowsy.
郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定され、かつ運転者に眠気が発生しているとして判定された場合、居眠り防止装置は音声発生装置１５による音声発生、振動発生装置１３による振動発生、表示装置１７による表示警告、匂い発生装置２０による香り発生、車内空調装置２１による風発生のいずれか、またはそれらを複合して実行し運転者に注意喚起を行う。 It was determined that the vehicle was running along a straight or gentle curve, such as a suburban road or a highway, where traffic signal traffic was long, and the driver was drowsy. In this case, the snoozing prevention device is any one of sound generation by the sound generation device 15, vibration generation by the vibration generation device 13, display warning by the display device 17, scent generation by the odor generation device 20, wind generation by the vehicle air conditioner 21, or those Is executed in combination to alert the driver.
郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定されてから生体情報の計測を行う利点は、そのような場所を走行しているときは、運転者の操作運動、車輌の方向転換、発車、停車、速度変化に伴う加速度の変化が市街地を走行しているときに比べ少なく、生体計測の際に雑音の原因となる体の動きが小さくなるため安定した計測が可能となり、眠気の判断が正しく行えることが期待できる。また、眠気が発生しやすい場所を走行しているときだけ生体情報を計測するため、それ以外のときは生体情報を計測する脈波センサー１４、心電センサー１８を休止することができるので省エネルギーが期待できる。 The advantage of measuring biometric information after it is determined that the vehicle is traveling along a straight or gentle curve, such as a suburban road or highway, and where the traffic signal interval is long When driving, there is less change in acceleration due to driver's operation movement, vehicle direction change, departure, stopping, and speed change compared to driving in urban areas, causing noise during biometric measurement become movement of the body is because it is possible to stably measure small, it is expected that the determination of the drowsiness can be performed correctly. In addition, since the biological information is measured only when traveling in a place where sleepiness is likely to occur, the pulse wave sensor 14 and the electrocardiographic sensor 18 that measure biological information can be paused at other times, thus saving energy. I can expect.
図６は常に車輌の走行状態と生体情報を計測し、運転者の眠気を検出した場合で、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していると判定した場合は、運転者へ注意喚起を行うが、郊外の道路や高速道路など、直線もしくは緩やかなカーブが続いており、交通信号機の間隔が長いような場所を走行していないと判定した場合は、運転者へ弱い注意喚起を行い、運転者への強い吃驚を与えないときの流れ図を示す。 Fig. 6 always shows the vehicle's driving condition and biometric information, and the driver's drowsiness is detected. Straight or gentle curves such as suburban roads and highways continue, and the traffic signal interval seems to be long. If it is determined that the vehicle is traveling in a safe place, the driver will be alerted, but a straight road or a gentle curve, such as a suburban road or a highway, will continue, and the traffic signal will have a long interval. When it is determined that the vehicle is not traveling, a weak alert is given to the driver, and a flow chart when the driver is not strongly surprised is shown.
図７にハンドル２に脈波センサー１４を配置した図を示す。図７に示したようにハンドル２の輪部に脈波センサー１４を複数配置して、運転者が輪部のどこを握っても運転者の両手、５指の先端腹部の何れかが、複数ある脈波センサーを１４のどれかに接するように配置する。脈波検出は指先端腹部が均一に接しているセンサー部より計測を行う。 FIG. 7 shows a view in which the pulse wave sensor 14 is arranged on the handle 2. As shown in FIG. 7, a plurality of pulse wave sensors 14 are arranged on the wheel part of the handle 2, so that no matter where the driver grips the wheel part, any one of the driver's hands and the tip of the five fingers is a plurality. A pulse wave sensor is placed in contact with any one of 14. Pulse wave detection is to measure from the sensor unit fingertip abdomen is uniformly contact.
図８に脈波センサー１４の光学発光部と光検出器の配置を示した図を示す。その構成は一つの光検出器と、酸素化ヘモグロビンの吸収係数が脱酸素化ヘモグロビン、水、脂肪よりも大きい波長領域である約８００ｎｍ〜約９００ｎｍの発光部とその波長領域以外となる長波長領域約９００ｎｍ〜１０００ｎｍもしくは短波長領域６００ｎｍ〜８００ｎｍの発光部の３つから成り立つ。
光検出器と酸素化ヘモグロビンの吸収係数が高い波長領域発光部とそれ以外の波長領域発光部の位置関係は光検出部を頂点とする二等辺三角形となるように配置され、２つの発光部は隣接するように配置される。
FIG. 8 is a diagram showing the arrangement of the optical light emitting unit and the photodetector of the pulse wave sensor 14. Its configuration is a single light detector, a light emitting portion of about 800 nm to about 900 nm, which is a wavelength region in which the absorption coefficient of oxygenated hemoglobin is larger than that of deoxygenated hemoglobin, water, and fat, and a long wavelength region other than the wavelength region. It consists of three light emitting portions of about 900 nm to 1000 nm or a short wavelength region of 600 nm to 800 nm.
The positional relationship between the wavelength region light emitting unit having a high absorption coefficient of the photodetector and oxygenated hemoglobin and the other wavelength region light emitting unit is arranged to be an isosceles triangle with the light detecting unit at the apex, and the two light emitting units are It arrange | positions so that it may adjoin.
検出する範囲は指先腹部が検出されるよう直径約１０ｍｍ程度以内となる。そのため光検出器と二つの発光部はその領域内に配置される。 Range to be detected is within a diameter of about 10mm so that finger belly is detected. Therefore, the photodetector and the two light emitting units are arranged in the region.
脈波検出には、酸素化ヘモグロビンの吸収係数が高い波長領域発光部とそれ以外の波長領域発光部は交互に発光し位相検波器を通して、それぞれの信号に分離する。その二つの出力を差分することにより、脈波振動に伴うヘモグロビン量の変化による光透過量として脈波が検出される。その際、振動などにより、脈波以外の光透過量の変化として検出される成分は酸素化ヘモグロビンの吸収係数が高い波長領域とそれ以外の波長領域では同様な信号成分となるため差分することにより相殺されることになる。 For pulse wave detection, the wavelength region light emitting unit having a high absorption coefficient of oxygenated hemoglobin and the other wavelength region light emitting units emit light alternately and are separated into respective signals through a phase detector. By calculating the difference between the two outputs, the pulse wave is detected as the light transmission amount due to the change in the hemoglobin amount associated with the pulse wave vibration. At this time, the component detected as a change in the amount of light transmission other than the pulse wave due to vibration or the like becomes a similar signal component in the wavelength region where the absorption coefficient of oxygenated hemoglobin is high and other wavelength regions. Will be offset.
検出するセンサーユニットを複数配置し、指が触れた場所の信号を検出する際、適切に光検出器と二つの発光部が指先に接触していると光検出器にはそれぞれの位相検波出力には矩形波が検出され、位相検波前の出力信号には２つの波長発光部による透過信号がヘモグロビン量による透過光の変化分の差程度の違いの出力差しか違わない出力が検出されることになる。そのため、指が当たっていない場合は位相検波出力に矩形波が検出されない。また指が均一に当たっていなく、どちらかの発光部と検出部に当たっているか、もしくは偏りが発生している場合は、位相検波前の出力信号に矩形波が発生することになるため、適切に測定位置に指先が当たっているセンサーユニットを判別でき、そのユニットからの信号を記録することができる。 When detecting the signal at the place where the finger touches by arranging multiple sensor units to detect, if the photodetector and the two light emitting units are in contact with the fingertips properly, the photodetector will output each phase detection output. In this case, a rectangular wave is detected, and the output signal before the phase detection detects an output that is the same as the difference between the transmitted signals of the two wavelength light emitting units and the difference in the amount of change in the transmitted light due to the amount of hemoglobin. Become. Therefore, if the finger is not hit the rectangular wave is not detected in the phase detection output. In addition, if the finger does not touch evenly and either the light emitting unit and the detection unit are touched, or if there is a bias, a rectangular wave will be generated in the output signal before phase detection, so the measurement position can be adjusted appropriately. to determine the sensor unit fingertip is hitting, it is possible to record the signals from the unit.
複数配置した脈波センサー１４により運転手がハンドルのどの場所を握っているかが判断できるため、緊握センサー１９として利用することができる。 Since a plurality of pulse wave sensors 14 can determine which part of the steering wheel the driver is holding, it can be used as the grip sensor 19.
図９には酸素化ヘモグロビンの吸収係数が脱酸素化ヘモグロビン、水、脂肪よりも大きい波長領域である約８００ｎｍ〜約９００ｎｍの発光部とその波長領域以外となる長波長領域約９００ｎｍ〜１０００ｎｍもしくは短波長領域６００ｎｍ〜８００ｎｍの発光部をもつ脈波検出方法のブロック図を示す。図１０には従来方式である１光源による脈波検出方法のブロック図を示す。 FIG. 9 shows a light emitting portion of about 800 nm to about 900 nm, which is a wavelength region in which the absorption coefficient of oxygenated hemoglobin is larger than that of deoxygenated hemoglobin, water, and fat, and a long wavelength region other than the wavelength region of about 900 nm to 1000 nm or short. It shows a block diagram of a pulse wave detecting method having a light emitting portion of the wavelength region 600 nm to 800 nm. The Figure 10 shows a block diagram of a pulse wave detecting method according to an light source is a conventional method.
単純な１つの光源で脈波計測を行う光電式脈波検出での脈波成分には毛細血管が広がりによる散乱の変化や、広がったことによる光路長の変化など、いろいろな成分が含まれている。その中で、光源の波長が800〜900nm程度の光が含まれている場合、その波長領域での酸素化ヘモグロビンの吸収係数は脱酸素化ヘモグロビン、水、脂肪の吸収係数よりも高いので、酸素化ヘモグロビン量の変化、つまり、動脈成分の変化が含まれていることになる。逆に、その波長領域以外の光源を用いると酸素化ヘモグロビン〜動脈の変化成分は少なくなる。つまり、波長800〜900nmの光源を用いたときの光検出変化量Pl800-900は図１２に示す数式(１)のようになる。 Pulse wave components in photoelectric pulse wave detection that measures pulse waves with a simple light source include various components such as changes in scattering due to the spread of capillaries and changes in optical path length due to the spread. Yes. Among them, when the light source has a wavelength of about 800 to 900 nm, the absorption coefficient of oxygenated hemoglobin in that wavelength region is higher than the absorption coefficient of deoxygenated hemoglobin, water, and fat. A change in the amount of hemoglobin, that is, a change in the arterial component is included. Conversely, when a light source other than the wavelength region is used, the oxygenated hemoglobin to arterial change component is reduced. That is, the light detection change amount Pl800-900 when a light source having a wavelength of 800 to 900 nm is used is expressed by Equation (1) shown in FIG.
ここで図１２中の数式(１)におけるAartery1800-900は波長800〜900[nm]を用いたときの動脈血成分の変化、Aother1800-900は波長800〜900[nm]を用いたときの、その他の変化による成分を示す。この中には動脈以外の脈波信号や振動雑音による信号が含まれる。一方、波長800〜900[nm]以外の光源、一般的には600-800[nm]領域や、900-1000[nm]領域などを用いたときの光検出変化量P1800-900は図１２に示す数式(２)のようになる。 In FIG. 12, A artery 1800-900 in Equation (1) changes the arterial blood component when using a wavelength of 800 to 900 [nm], and A other1800-900 uses a wavelength of 800 to 900 [nm]. Indicate components due to other changes. These include pulse wave signals other than arteries and signals due to vibration noise. On the other hand, the light detection change amount P 1800-900 when using a light source other than a wavelength of 800 to 900 [nm], generally 600-800 [nm] region, 900-1000 [nm] region, etc. is shown in FIG. (2) shown below.
このとき、動脈血の吸収係数の差から、図１２に示す数式(３)のようになる。一方、波長の違う２つの光源と光検出器の光路を、ほぼ同じ位置に配置した場合、その領域の振動による変化量は、ほぼ同じになると予想される。そのため２つの光源および光検出器を近接して配置した場合、図１２に示す数式(４)のようになる。そのため、波長800〜900[nm]の光源を用いたときの光検出変化量から波長800〜900[nm]以外の光源を用いたときの光検出変化量を引くと、図１２に示す数式(５)となり、動脈血の変動分が検出されることになる。 At this time, the difference in absorption coefficient of the arterial blood is as shown in Equation (3) shown in FIG. 12. On the other hand, when the optical paths of two light sources and photodetectors having different wavelengths are arranged at substantially the same position, the amount of change due to vibration in that region is expected to be substantially the same. Therefore, when the two light sources and the photodetector are arranged close to each other, the formula (4) shown in FIG. 12 is obtained. Therefore, when the light detection change amount when using a light source other than the wavelength 800 to 900 [nm] is subtracted from the light detection change amount when the light source having a wavelength of 800 to 900 [nm] is used, the mathematical formula shown in FIG. 5), and the variation of arterial blood is detected.
実際には２つの光源を同時に発光させそれぞれの光検出器で検出した場合、光路近接しているためそれぞれの信号を分離することはできない。そのため、光検出器は１つとし、それぞれの光源の発光を時間分割して交互に発光させ信号を分離することとなる。このとき、それぞれの信号成分は別時間の信号となるので、違う振動成分を検出することになるが、検出したい生体信号である0.1〜100[Hz]よりも十分高い周波数で切り替えることにより、その帯域の信号はほぼ同じ振動の信号として検出されることとなる。 Actually, when two light sources emit light at the same time and are detected by the respective photodetectors, the signals cannot be separated because they are close to the optical path. For this reason, the number of photodetectors is one, and the light emission of each light source is time-divided to alternately emit light to separate signals. At this time, since each signal component becomes a signal at a different time, a different vibration component will be detected, but by switching at a frequency sufficiently higher than 0.1 to 100 [Hz] which is a biological signal to be detected, The band signal is detected as a signal having substantially the same vibration.
従来手法である単一光源での脈波スペクトルと本方式である２波長発光光源による脈波スペクトルの結果を図１１に示す。図中横軸は周波数、縦軸は単一光源、２波長光源で脈波を計測したときの出力値で受光強度となっている。受光強度は、それぞれの回路構成が異なるので、単純に比較ができない。そこで、それぞれの脈波中心周波数のパワーの値を１として規格化し、1光源による方法と２光源による方法で得られた結果を比較している。 FIG. 11 shows the results of the pulse wave spectrum obtained from a single light source that is a conventional method and the pulse wave spectrum obtained from a two-wavelength light source that is the present method. In the figure, the horizontal axis represents frequency, and the vertical axis represents the received light intensity as an output value when a pulse wave is measured with a single light source and a two-wavelength light source. The received light intensity cannot be simply compared because each circuit configuration is different. Therefore, the power value of each pulse wave center frequency is normalized as 1, and the results obtained by the method using one light source and the method using two light sources are compared.
尚、上述の発明は、乗用四輪自動車に限らず、鉄道、船舶、二輪自動車等の移動手段にも応用できることは云うまでもない。
Needless to say, the above-described invention is applicable not only to passenger four-wheeled vehicles but also to moving means such as railways, ships, and two-wheeled vehicles.
１…運転手
２…ハンドル
３…加速度センサー
４…振動センサー
５…情報処理装置
６…地図データ
７…車両
８…アクセル
９…ブレーキ
１０…クラッチ
１１…シフトレバー
１２…シート
１３…振動発生装置
１４…脈波センサー
１５…音声発生装置
１６…自動車用衛星航行システム装置
１７…表示装置
１８…心電センサー
１９…緊握センサー
２０…匂い発生装置
２１…車内空調装置
２２…酸素化ヘモグロビンの吸収係数が高い波長領域発光部
２３…酸素化ヘモグロビンの吸収係数が低い波長領域発光部
２４…光検出器
２５…指
２６…電流電圧変換回路
２７…アナログスイッチ
２８…ハイパスフィルター
２９…ローパスフィルター
３０…位相検波器
３１…クロック発振器
３２…差動増幅器
３３…増幅器
３４…Ａ／Ｄ変換器
DESCRIPTION OF SYMBOLS 1 ... Driver 2 ... Handle 3 ... Acceleration sensor 4 ... Vibration sensor 5 ... Information processing device 6 ... Map data 7 ... Vehicle 8 ... Accelerator 9 ... Brake 10 ... Clutch 11 ... Shift lever 12 ... Seat 13 ... Vibration generator 14 ... Pulse wave sensor 15 ... sound generator 16 ... automotive satellite navigation system device 17 ... display device 18 ... electrocardiographic sensor 19 ... grip sensor 20 ... odor generator 21 ... in-vehicle air conditioner 22 ... high absorption coefficient of oxygenated hemoglobin Wavelength region light emitting unit 23... Wavelength region light emitting unit 24 having a low absorption coefficient of oxygenated hemoglobin... Photodetector 25... Finger 26. ... Clock oscillator 32 ... Differential amplifier 33 ... Amplifier 34 ... A / D converter
Claims (6)
車両の走行状態を検知するための複数のセンサーから構成される車輌状態検知手段を車輌内部に備え、
前記車輌状態検知手段には自動車用衛星航行システムを含み、
前記運転者状態検知手段からの検知情報に基づいて、運転者の眠気状態を判定する情報処理装置を備え、
当該情報処理装置は、前記判定の結果、眠気が発生していると判定された場合に、前記車輌状態検知手段からの情報に応じて運転者に対して警告するか否かを判定することを特徴とする車輌居眠り防止装置。 It has a driver state detection means composed of a plurality of sensors for detecting information from the driver on the steering wheel,
Vehicle state detection means comprising a plurality of sensors for detecting the running state of the vehicle is provided inside the vehicle,
The vehicle state detection means includes an automotive satellite navigation system,
An information processing device that determines the drowsiness state of the driver based on detection information from the driver state detection means,
If it is determined that drowsiness is occurring as a result of the determination, the information processing apparatus determines whether to warn the driver according to information from the vehicle state detection means. A vehicle dozing prevention device.
前記運転者状態検知手段は、緊握センサー、脈波センサー、心電センサーを含むことを特徴とする車輌居眠り防止装置。 The vehicle doze prevention device according to claim 1,
The vehicle doze prevention device, wherein the driver state detection means includes a grip sensor, a pulse wave sensor, and an electrocardiogram sensor.
前記車輌状態検知手段は、加速度センサー、振動センサーを少なくとも含むことを特徴とする車輌居眠り防止装置。 The vehicle doze prevention device according to claim 1,
The vehicle state detection means includes at least an acceleration sensor and a vibration sensor.
音声発生装置、表示装置、匂い発生装置、車内空調装置、振動発生装置のうち少なくとも２つを警告手段として車輌内に備え、
前記警告すると判定された場合には、前記車輌状態検知手段の検知結果に応じて、前記情報処理装置が前記警告内容を決定することを特徴とする車輌居眠り防止装置。 The vehicle doze prevention device according to claim 1,
A sound generator, a display device, an odor generator, an in-vehicle air conditioner, and a vibration generator are provided in the vehicle as warning means,
When it is determined that the warning is issued, the information processing apparatus determines the warning content according to a detection result of the vehicle state detection means.
前記脈波センサーは車輌内部のバンドル部に設けられ、
当該脈波センサーが、８００ｎｍ〜９００ｎｍの波長を有する第一発光部と、９００ｎｍ〜１０００ｎｍもしくは６００ｎｍ〜８００ｎｍの第二発光部を備え、さらに、当該発光部を頂点とする二等辺三角形となるように検出部が配置されることを特徴とする車輌居眠り防止装置。 The vehicle dozing prevention device according to claim 2,
The pulse wave sensor is provided in a bundle portion inside the vehicle,
The pulse wave sensor includes a first light emitting unit having a wavelength of 800 nm to 900 nm and a second light emitting unit of 900 nm to 1000 nm or 600 nm to 800 nm, and further, an isosceles triangle having the light emitting unit as a vertex. A vehicle doze prevention device, wherein a detection unit is arranged.
前記２つの発光部は隣接するように配置され、酸素化ヘモグロビンの吸収係数が高い波長領域発光部とそれ以外の波長領域発光部は交互に発光し位相検波器を通して、それぞれの信号に分離し、二つの出力を差分することにより、脈波振動に伴うヘモグロビン量の変化による光透過量として脈波が検出されることを特徴とする車輌居眠り防止装置。 The vehicle doze prevention device according to claim 5,
The two light emitting units are arranged adjacent to each other, and the wavelength region light emitting unit having a high absorption coefficient of oxygenated hemoglobin and the other wavelength region light emitting units emit light alternately and are separated into respective signals through a phase detector, A vehicle doze prevention device characterized in that a pulse wave is detected as a light transmission amount due to a change in the amount of hemoglobin accompanying pulse wave vibration by subtracting two outputs.
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