JP7256499B2 - Measuring method and measuring device for road surface water film thickness - Google Patents

Measuring method and measuring device for road surface water film thickness Download PDF

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JP7256499B2
JP7256499B2 JP2019221962A JP2019221962A JP7256499B2 JP 7256499 B2 JP7256499 B2 JP 7256499B2 JP 2019221962 A JP2019221962 A JP 2019221962A JP 2019221962 A JP2019221962 A JP 2019221962A JP 7256499 B2 JP7256499 B2 JP 7256499B2
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明宏 藤本
忠幸 山田
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University of Fukui
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本発明は車両に搭載して路面の水膜厚さを走行しながら測定する方法及び測定装置に関するものである。 TECHNICAL FIELD The present invention relates to a method and a measuring device mounted on a vehicle for measuring the thickness of water film on a road surface while the vehicle is running.

凍結防止剤散布は，路面上の水分に塩化物を混合させることで、その凝固点を降下させて路面凍結を防止する冬期道路管理方法の一つである。凍結防止剤の副次的影響としての塩害問題や道路予算の縮減を背景に、結防止剤散布の効率化は依然として重要な課題である。 Antifreezing agent spraying is one of the winter road management methods to prevent road surface freezing by lowering the freezing point of the road surface by mixing chloride with the moisture on the road surface. Against the background of salt damage as a secondary effect of anti-freezing agents and reduction of road budget, efficiency of anti-caking agent spraying is still an important issue.

現状では、散布前に何時・どの位の量を散布すればよいかを道路管理者が判断することは容易でない。その理由は、路面凍結の発生や凍結防止剤の散布量に関係する路面温度、路面水分量および路面塩分量の把握が難しいことにある。特に、路面水分量は、降雨、路面雪氷の融解、路肩からの融雪水の流入、蒸発・凝縮、通過車両による飛散、道路勾配に伴う排水など、様々な影響を受けて時間的および空間的に多様に変化するために把握が難しい。 At present, it is not easy for road administrators to determine when and how much to spray before spraying. The reason for this is that it is difficult to grasp the road surface temperature, road surface water content, and road surface salt content, which are related to the occurrence of road surface freezing and the amount of antifreeze sprayed. In particular, the road surface moisture content is affected by various factors such as rainfall, melting of snow and ice on the road surface, inflow of melted snow water from the road shoulder, evaporation/condensation, scattering by passing vehicles, and drainage due to the road gradient. It is difficult to grasp because it changes in various ways.

したがって、凍結防止剤散布の効率化を促進させるには、縦断勾配・線形、橋梁・トンネル区間、日向・日陰区間、舗装種別などの道路条件に伴う路面水膜厚の路線分布を少なくとも散布時の段階では正確に捉えておくことが肝要になる。また、路面水膜厚の路線分布を把握するには、走行しながら連続的に測定するような装置が必要になる。 Therefore, in order to promote the efficiency of antifreezing agent spraying, it is necessary to estimate the road surface water film thickness due to road conditions such as longitudinal gradient/alignment, bridge/tunnel section, sunny/shaded section, pavement type, etc. at least at the time of spraying. It is important to get it right at each stage. In addition, in order to grasp the route distribution of the road surface water film thickness, it is necessary to have a device that continuously measures the road surface while the vehicle is running.

路面水膜厚の測定方法には、吸水式、画像解析式、非接触式、埋設式などが挙げられる。
吸水式は吸水紙を用いて路面上の水分を吸い取り、その重量を厚さに換算して求める方法である。ただし、この方法は現道路では安全上難しく、労力や時間の関係から路線分布を把握することはできない。
従来においては、路面の状態を判定する技術に関しては色々知られている。 Methods for measuring the road surface water film thickness include a water absorption method, an image analysis method, a non-contact method, and an embedded method.
The water absorption method is a method in which water absorption paper is used to absorb moisture on the road surface, and the weight is converted into thickness. However, this method is difficult for safety on existing roads, and it is not possible to grasp the route distribution due to labor and time constraints.
Conventionally, various techniques for judging road surface conditions are known.

例えば、特開２００８－１２２２５０号に係る「路面状況判定方法」は、センサー表面がおおよそ路面の高さになるように舗装に埋め込み、電気抵抗値などから路面雪氷分類、塩分濃度、水・氷膜厚を計測する方法である。 For example, the "road surface condition determination method" according to Japanese Patent Application Laid-Open No. 2008-122250 is embedded in the pavement so that the sensor surface is approximately at the height of the road surface, and the road surface snow and ice classification, salinity concentration, water / ice film from the electrical resistance value etc. It is a method of measuring thickness.

特願２０１７－５４６３８９に係る「路面状態判定装置、撮像装置、撮像システムおよび路面状態判定方法」は、温度検出部と撮像装置とを備え、路面の温度、撮像された路面を表す画像を取得する。また、画像に含まれる画素の輝度に基づいて、路面が濡れているか乾いているかを判定し、且つ、路面の温度に関連する信号に基づいて、路面が凍結しているか否かを判定する装置である。 ``Road surface condition determination device, imaging device, imaging system, and road surface condition determination method'' according to Japanese Patent Application No. 2017-546389 includes a temperature detection unit and an imaging device, and acquires an image representing the temperature of the road surface and the captured road surface. . A device for determining whether the road surface is wet or dry based on the brightness of the pixels included in the image, and determining whether the road surface is frozen based on a signal related to the temperature of the road surface. is.

特開２０１５－３８５１６に係る「路面状態推定方法」は、タイヤ内に設置された加速度センサーで検出したタイヤ振動の時系列波形と走行中の路面温度とタイヤ発生音などから、積雪、凍結、シャーベット、圧雪、湿潤、乾燥などの路面雪氷分類を判定する方法である。 The "road surface condition estimation method" according to Japanese Patent Application Laid-Open No. 2015-38516 is based on the time-series waveform of tire vibration detected by an acceleration sensor installed in the tire, the road surface temperature during driving, and the sound generated by the tire. , compacted snow, wet, and dry.

特開２０１１－５３１８４に係る「マイクロ波センサ」は、マイクロ波受信機が路面等の対象物から放出される微弱なマイクロ波帯熱雑音を計測し、赤外線放射温度計が対象物から放出される赤外線から物理温度を計測することで積雪、凍結、湿潤、乾燥等の対象物の表面状態を判別する装置である。 The "microwave sensor" according to Japanese Patent Application Laid-Open No. 2011-53184 measures weak microwave thermal noise emitted from an object such as a road surface by a microwave receiver, and an infrared radiation thermometer is emitted from the object. It is a device that determines the surface state of an object such as snow cover, frozen, wet, dry, etc. by measuring physical temperature from infrared rays.

特開２００６－２５０６３４に係る「被覆塩水計測装置および被覆塩水計測方法」は、路面に向けて電波を照射するとともに反射した電波を受信し、照射した電波に対する受信した電波の変化を基に被覆水の濃度にかかわらず膜厚を特定することができる装置である。 "Coated salt water measuring device and coated salt water measuring method" according to Japanese Patent Application Laid-Open No. 2006-250634 irradiates radio waves toward a road surface and receives reflected radio waves, and detects coated water based on the change in the received radio waves with respect to the irradiated radio waves. It is an apparatus that can specify the film thickness regardless of the concentration of

一方、道路に撒かれた塩分はタイヤから水はねにより空中に飛散し、車両に付着して車体の腐食を促進させる。道路上の塩分に起因した車体の腐食を評価するには、タイヤから車両に飛散する塩量を測定する必要がある On the other hand, the salt sprinkled on the road splashes from the tires into the air, adheres to the vehicle, and accelerates the corrosion of the vehicle body. In order to evaluate car body corrosion caused by salt on the road, it is necessary to measure the amount of salt that scatters from the tires to the vehicle.

特開２００８－１２２２５０号に係る「路面状況判定方法」"Road condition determination method" according to Japanese Patent Application Laid-Open No. 2008-122250 特願２０１７－５４６３８９に係る「路面状態判定装置、撮像装置、撮像システムおよび路面状態判定方法」"Road surface condition determination device, imaging device, imaging system, and road surface condition determination method" according to Japanese Patent Application No. 2017-546389 特開２０１５－３８５１６に係る「路面状態推定方法」"Road surface state estimation method" according to JP 2015-38516 特開２０１１－５３１８４に係る「マイクロ波センサ」"Microwave sensor" according to JP-A-2011-53184 特開２００６－２５０６３４に係る「被覆塩水計測装置および被覆塩水計測方法」"Coated salt water measuring device and coated salt water measuring method" according to JP-A-2006-250634

このように路面水膜厚測定には様々な装置や方式が存在するが、これまでの技術は道路に埋設して直接的に路面水膜厚を測定するか、あるいは路面の水分と接触させずに電磁波の放射と反射を基に間接的に路面水膜厚を測定するであった。接触式かつ車両に搭載して連続的に路面水膜厚を測定する装置はこれまでに存在しない。また、タイヤから車両に飛散する塩量（車両飛散塩量）を測定する技術も存在しない。
本発明が解決しようとする課題はこれら問題点であり、車両に搭載して路面の水膜厚さを測定する方法及び測定装置、並びに車両飛散塩量を測定する方法及び測定装置を提供する。 In this way, there are various devices and methods for measuring road surface water film thickness. Secondly, the road surface water film thickness was measured indirectly based on the radiation and reflection of electromagnetic waves. So far, there is no contact-type, vehicle-mounted, continuous measuring device for road surface water film thickness. Also, there is no technology for measuring the amount of salt that scatters from tires to a vehicle (vehicle-scattered salt amount).
The problem to be solved by the present invention is to solve these problems, and to provide a method and a measuring device mounted on a vehicle to measure the thickness of the water film on the road surface, and a method and a measuring device to measure the amount of splashed salt on the vehicle.

本発明は、車載式塩分濃度センサーを利用して路面上の水分の塩分濃度とタイヤによって飛散した水分量を求め、さらに路面水膜厚を評価する方法および装置（タイヤ水はね式路面水膜厚装置）である。また、路面上の水分の塩分濃度とタイヤによって飛散した水分量から車両に飛散する塩分の質量を算出する方法である。 The present invention uses an in-vehicle salinity sensor to obtain the salinity of water on the road surface and the amount of water splashed by tires, and a method and apparatus for evaluating the road surface water film thickness (tire water splash type road surface water film). thickness device). Another method is to calculate the mass of salt that scatters to the vehicle from the salt concentration of the water on the road surface and the amount of water that scatters from the tires.

すなわち、車両のタイヤが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来るようにした路面の水膜厚測定方法である。
車両のタイヤハウス内に塩分濃度センサーを取付け、路面の塩分濃度Cst、およびセンサー部に供給する規定の塩溶液(塩分濃度Csv、質量Mv)とタイヤ水はね量Mtとが混合した塩分濃度Csmixを測定し、塩分濃度がCsvからCsmixへの変化よりタイヤ水はね量Mtを推定し、所定の路面水膜厚さHwとMtの関係式を用いて路面水膜厚さHwを求めることが出来る。 In other words, this is a road surface water film thickness measuring method in which water existing on the road surface is splashed up by the rotation of a vehicle tire, thereby measuring the road surface water film thickness H w (mm).
A salinity concentration sensor is installed in the tire house of the vehicle, and the salt concentration C st of the road surface and the specified salt solution (salinity concentration C sv , mass M v ) supplied to the sensor are mixed with the tire water splash amount M t . The salinity concentration C smix is measured, and the tire water splash amount M t is estimated from the change in the salinity concentration from C sv to C smix . The road surface water film thickness H w can be obtained.

また、車両のタイヤが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来るようにした路面の水膜厚測定装置である。
タイヤ後方の泥除け部に塩分濃度センサーを取り付け、タイヤ泥除け部にはセンサー部を規定の塩溶液(塩分濃度Csv、質量Mv)で濡らしておき、この塩溶液とタイヤ水はね量Mtとが混合した塩分濃度Csmixを測定するために、塩分濃度センサーに供給流導水スリット、混合部／水はねコレクター、水はね保護カバー、導水板及びセンサ－面の水分除去装置が付加され、規定の塩溶液は車内タンクからポンプによって上記供給水導水スリットを通して飛散水と供給水とが混合される混合部／水はねコレクターを設けている。 In addition, the road surface water film thickness measuring device is capable of measuring the road surface water film thickness H w (mm) by splashing water existing on the road surface by rotating the vehicle tires.
A salt concentration sensor is attached to the mudguard behind the tire , and the tire mudguard is wetted with a specified salt solution (salinity concentration C sv , mass M v ). In order to measure the salinity C smix mixed with the salinity sensor, a feed stream water guide slit, a mixing section/water splash collector, a water splash protection cover, a water guide plate and a moisture removal device on the sensor surface are added to the salinity sensor. A specified salt solution is provided with a mixing section/water splash collector in which splash water and supply water are mixed through the supply water conduit slit by a pump from an in-vehicle tank.

本発明は，走行しながら路面水膜厚の空間的な連続データを取得すること出来る。また、路面水膜厚を含む路面状態、気象条件、交通条件などの入力条件から将来の凍結路面の発生の有無を路面すべり摩擦係数で予測し凍結防止剤の最適な散布量を推定する技術に、路面水膜厚の空間連続データを入力することで将来の路面すべり摩擦係数マップや凍結防止剤の最適散布条件マップの作成が出来る。 The present invention can acquire spatially continuous data of road surface water film thickness while driving. In addition, we have developed a technology that predicts the occurrence of future frozen road surfaces based on road slip coefficients of friction based on input conditions such as road surface conditions including water film thickness, weather conditions, and traffic conditions, and estimates the optimal amount of antifreeze to be sprayed. By inputting spatial continuous data of road surface water film thickness, it is possible to create a future road surface slip friction coefficient map and an optimum spraying condition map of anti-freezing agents.

本発明の装置は積雪地のみならず、非積雪地や冬期以外のハイドロプレーニング現象によるスリップ抑止対策にも活用が出来る。
車体に飛散する塩分量を測定し、凍結防止剤が車体に及ぼす塩害の影響を評価でき、車体への塩害防止や遅延の技術開発の測定装置となる。そして、冬期道路の安全性と塩害の影響を考慮して、今後の凍結防止剤散布のあり方について検討する際の基礎資料に必要なデータを測定できる。 The device of the present invention can be used not only in snowy areas but also in non-snowy areas and as a countermeasure against slipping caused by hydroplaning in non-winter seasons.
By measuring the amount of salt that scatters on the car body, it is possible to evaluate the effects of salt damage that antifreeze agents have on the car body. Then, considering the safety of roads in winter and the effects of salt damage, it is possible to measure the data necessary for basic data when considering the future application of antifreeze agents.

タイヤ水はね式の路面水膜厚装置を表している実施例。An embodiment showing a tire splash type road water film thickness device. 図１のＡ部拡大図。FIG. 2 is an enlarged view of part A in FIG. 1; タイヤ水はね式の路面水膜厚装置の具体例。A specific example of a tire water splash type road surface water film thickness device. タイヤ水はね式の路面水膜厚装置の路面水膜厚装置の好適形状と設計条件式。Preferred shape and design condition formula of road surface water film thickness device of tire water splash type road surface water film thickness device. タイヤ水はね式の路面水膜厚装置の初期設定の方法。Method of initial setting of tire water splash type road surface water film thickness device. 走行速度v = 20、40、60および80 km/hにおけるHwとMtの関係を示している。The relationship between H w and M t is shown at running speeds v = 20, 40, 60 and 80 km/h. HwとMtの関係式に含まれる係数ａと走行速度ｖの関係を表しているグラフ。Graph showing the relationship between the coefficient a and the running speed v included in the relational expression between Hw and Mt. （１）は供給水及び飛散水と混合塩分濃度の関係式、（２）は供給水の塩分濃度を示す式、（３）は飛散水の塩分濃度を示す式、（４）は式（１）に式（２）と（３）を代入して、Mtを左辺にして整理した場合。(1) is the relational expression between the supply water and the splash water and the mixed salt concentration, (2) is the formula showing the salt concentration of the supply water, (3) is the expression showing the salt concentration of the splash water, and (4) is the formula (1 ) and rearranged with M t on the left side.

以下、図、式を用いて本発明の実施形態の一例を具体的に説明する。
図１はタイヤ水はね式の路面水膜厚装置を表している実施例であり、図２は上記タイヤ水はね式の路面水膜厚装置のＡ部拡大図を示し、図３はタイヤ水はね式の路面水膜厚装置の具体例である。同図の１ａはタイヤ、１ｂは別のタイヤを示し、これら各タイヤ１ａ，１ｂが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来る。具体的には、車載式塩分濃度センサーを車両のタイヤハウス内に装着し、タイヤからセンサー部に飛散した水分(以下，飛散水という)から路面塩分濃度Cts(%)を測定する。センサー及びその他構成部材はタイヤハウス内に取り付けられていれば良く好ましくは泥除け部、より好ましくはタイヤ後方側の泥除け部に装着される。取り付け形態は発明の目的を達成できれば特に限定されずタイヤハウス壁面への直接に取付け、支持部材を介した取付けでもよい。また、車内からの供給される塩溶液(以下，供給水という)によってセンサー部を濡らした状態にして飛散水をセンサーに接触させ，供給水と飛散水の混合塩分濃度Csmix(%)を測定する。 An example of an embodiment of the present invention will be specifically described below with reference to figures and formulas.
FIG. 1 shows an embodiment showing a tire water splash type road surface water film thickness device, FIG. 2 shows an enlarged view of part A of the tire water splash type road surface water film thickness device, and FIG. This is a specific example of a water splash type road surface water film thickness device. In the figure, 1a indicates a tire, and 1b indicates another tire. When these tires 1a and 1b rotate, water existing on the road surface is splashed up, thereby measuring the road surface water film thickness Hw (mm). can do Specifically, an in-vehicle salinity sensor is installed in the tire house of the vehicle, and the road surface salinity C ts (%) is measured from the water splashed from the tire to the sensor (hereinafter referred to as splash water). The sensor and other structural members may be installed inside the tire housing, preferably the mudguard, more preferably the mudguard on the rear side of the tire. The form of attachment is not particularly limited as long as the object of the invention can be achieved, and may be attached directly to the tire housing wall surface or via a support member. In addition, the sensor is wetted with a salt solution (hereinafter referred to as “supply water”) supplied from inside the vehicle, and the sprayed water is brought into contact with the sensor to measure the mixed salt concentration C smix (%) of the supplied water and the sprayed water. do.

1秒間あたりの供給水および飛散水の重量をMiおよびMt(g/s)とすると、Csmixは図８の（１）に示す式で与えられる。
図８（１）に示すMisおよびMtsは1秒間に流れる供給水および飛散水に含まれる塩重量(g/s)である。ここで、供給水の塩分濃度Cis(%)および飛散水の塩分濃度Cts(%)は、それぞれ図８の（２）と図８の（３）に示す式で与えられる。
そして図８（１）に図８（２）と（３）の式を代入して、Mtを左辺にして整理すると図８の（４）に示す式が得られる。
上記図８の式（４）において、MiおよびCisは設定項目であり、CtsおよびCsmixは測定されるため、右辺の未知数は無くなり、Mtは得られる。最後に、路面水膜厚Hw(mm)は後述に記載するHwとMtの関係式より求められる． Assuming that the weights of supplied water and splashed water per second are M i and M t (g/s), C smix is given by the formula shown in FIG. 8(1).
M is and M ts shown in FIG. 8(1) are the salt weights (g/s) contained in the supply water and the splash water flowing for one second. Here, the salinity concentration C is (%) of the supply water and the salinity concentration C ts (%) of the splash water are given by the equations shown in (2) and (3) in FIG. 8, respectively.
8(2) and (3) are substituted for FIG. 8(1), and the equation shown in FIG. 8(4) is obtained by arranging M t on the left side.
In equation (4) of FIG. 8, M i and C is are set items, and C ts and C s mix are measured, so the unknowns on the right side are eliminated and M t is obtained. Finally, the road surface water film thickness H w (mm) is obtained from the relational expression between H w and M t described later.

図４は図３のタイヤ水はね式の路面水膜厚装置における供給流、飛散流、混合流の流れを表している。
図１、図４に表しているように、タイヤ１ｂの後方に設けた後輪センサーは、塩分濃度センサー２に供給流導水スリット３、混合部／水はねコレクター４、導水板５、水はね保護カバー６及びセンサー面の水分除去装置７が付加されている。規定の塩溶液は車内タンクからポンプによって供給流導水スリット３を通して混合部／水はねコレクター４に供給される。供給流導水スリット３は車に取り付けたタンクから供給流を混合部/水はねコレクター４に導くものであり、タンクから混合部／水はねコレクター４までに水分が損失しない形状にする。混合部／水はねコレクター４は飛散流と供給流を混合させる場所であり、両者が十分に混合するような形状にする。導水板５は飛散流と供給量の混合流を塩分濃度センサー２上部に集める。そのために、同図のように塩分濃度センサー２上部に混合流が集まるような形状が好ましい。また、装置表面の水分がこぼれ落ちないように上部に溝や傾斜を設けることを推奨する。水はね保護カバー６は塩分濃度センサー２に飛散流が直接接触しないように設置する。混合部/水はねコレクター４でタイヤ１ｂからの水分と混合させ、その混合液体の塩分濃度を下部に設置した塩分濃度センサー２で測定する。また、塩分濃度センサー２にはセンサー面の水分除去装置７が取り付けられており、塩分濃度センサー２の水分を感知するとその水分は拭き取られる。 FIG. 4 shows the flow of the supply flow, the splash flow and the mixed flow in the tire water splash type road surface water film thickness device of FIG.
As shown in FIGS. 1 and 4, the rear wheel sensor provided behind the tire 1b has a supply flow water guide slit 3, a mixing part/water splash collector 4, a water guide plate 5, a water A spring protective cover 6 and a sensor surface moisture eliminator 7 are added. A defined salt solution is supplied by a pump from an on-board tank through a supply flow conduit slit 3 to a mixer/splash collector 4 . The feed channel slit 3 directs the feed stream from the vehicle mounted tank to the mixer/splash collector 4 and is shaped to prevent water loss from the tank to the mixer/splash collector 4 . The mixing section/splash collector 4 is where the splash and feed streams are mixed, and is shaped to ensure sufficient mixing of the two. The water guide plate 5 collects the mixed flow of the splash flow and the supply flow above the salinity concentration sensor 2 . For this reason, it is preferable to have a shape in which the mixed flow gathers above the salinity concentration sensor 2 as shown in FIG. It is also recommended that the top of the device be grooved or sloped to prevent water from spilling on the surface of the device. The water splash protection cover 6 is installed so that the splashing flow does not come into direct contact with the salinity concentration sensor 2. - 特許庁The mixture is mixed with water from the tire 1b in the mixing section/water splash collector 4, and the salinity concentration of the mixed liquid is measured by the salinity concentration sensor 2 installed at the bottom. Also, the salt concentration sensor 2 is provided with a water remover 7 on the sensor surface, and when water is detected on the salt concentration sensor 2, the water is wiped off.

図５はタイヤ水はね式の路面水膜厚装置の初期設定の方法を示す。ステップS101では車両のタイヤハウス内に取付場所を設定する。取付場所はタイヤからの水はね（飛散水量）が当たる箇所かつ最低地上高以上に設置する（飛散水量は多すぎても少なすぎても（S109）の測定精度は低下する）。S102では取付角度を設定する。塩分濃度センサー面を飛散水量に対して直行するように設置し、（S103）が満たされるまで仰角を90°側に変更する。S103では取付角度を調整する。飛散水量および供給水量がセンサー面を流れているかを確認し、流れていなければS102に戻り、取付角度を再設定する。流れていれば、次のステップS104に進む。S104では、供給水の塩分濃度を設定する。飛散水量の塩分濃度との差が大きくなるように設定する（通常は路面塩分濃度が薄いため、塩分濃度は濃いほど望ましい）。S105では供給水量を設定するが、次のステップS106の条件が満たされるまで供給水量を増やす。S106では混合塩分濃度によって供給水量が適当かを判定する。具体的には対象道路の高速度域で混合塩分濃度が供給水量と飛散水量の塩分濃度の範囲の中間程度（中間よりやや薄い方が望ましい）であれば、次のステップS107に進み、そうでなければS105に戻る。S107では飛散水量を前述の式(４)に従って求める。S108では路面水膜厚を推定する。次のように路面水膜厚と飛散水量の関係式を作成し、路面水膜厚を求める。様々な走行速度かつ水膜厚の路面において走行試験を実施し、路面水膜厚・飛散水量・走行速度を計測する。路面水膜厚を飛散水量と走行速度を説明変数として整理する。S109では路面水膜厚の精度を検証し、測定精度が設定範囲以内であれば完了し、そうでなければS101に戻り、再設定を行う。 FIG. 5 shows the initial setting method of the tire water splash type road surface water film thickness device. In step S101, a mounting location is set in the tire house of the vehicle. The installation location should be where the water splashes from the tire (splashing water amount) hit and above the minimum ground clearance. The mounting angle is set in S102. Install the surface of the salinity concentration sensor so that it is perpendicular to the amount of splashed water, and change the elevation angle to the 90° side until (S103) is satisfied. In S103, the mounting angle is adjusted. Check whether the amount of splashed water and the amount of supplied water are flowing on the sensor surface, and if not, return to S102 and reset the mounting angle. If it is flowing, proceed to the next step S104. In S104, the salt concentration of the supply water is set. Set so that the difference between the amount of sprayed water and the salinity concentration is large (since road surface salinity is usually low, the higher the salinity, the better). In S105, the amount of supplied water is set, but the amount of supplied water is increased until the conditions of the next step S106 are satisfied. In S106, it is determined whether the amount of supplied water is appropriate based on the mixed salt concentration. Specifically, if the mixed salt concentration in the high-speed area of the target road is in the middle of the salt concentration range of the amount of supplied water and the amount of sprayed water (preferably slightly thinner than the middle), proceed to the next step S107. If not, return to S105. In S107, the amount of splashed water is calculated according to the above formula (4). In S108, the road surface water film thickness is estimated. The road surface water film thickness is obtained by creating the relational expression between the road surface water film thickness and the amount of splashed water as follows. We will conduct running tests on road surfaces with various running speeds and water film thickness, and measure the road surface water film thickness, the amount of splashed water, and the running speed. The road surface water film thickness is organized using the amount of splashed water and the traveling speed as explanatory variables. In S109, the accuracy of the road surface water film thickness is verified, and if the measurement accuracy is within the set range, the process is completed.

所定のHwとMtの関係は、予め予備実験で求めておくことができる。その求め方の一例、求めた関係式の一例を以下に述べる。
路面の水膜厚Hwとタイヤ水はね量Mtの関係を調べるための走行実験を苫小牧寒地試験道路で行った。実験は湿潤路面で行われ、Hwを変えて繰り返し実施した。Hwは吸水紙を用いて採取した路面上水分の重量から、Mtはタイヤ後輪の泥除け部に取り付けたスポンジの走行前後の重量差から求めた。
図６は走行速度v = 20、40、60および80 km/hにおけるHwとMtの関係を示している。同図に示すように、HwとMtの関係はＨｗ＝ａＭｔ 0.45で近似して表される。
ここで、関数のａと走行速度ｖの関係は図７に表しているように、走行速度ｖの増加につれてａは減少し、その関係はa=0.43exp(-0.007V)で表される。
最終的にＨｗ＝ａＭｔ0.45 a=0.43exp(-0.007V) （Ｖ：走行速度）の関係式が得られる。 A predetermined relationship between H w and M t can be obtained in advance by preliminary experiments. An example of how to obtain the value and an example of the obtained relational expression will be described below.
A running test was conducted on the Tomakomai Cold Region Test Road to investigate the relationship between the water film thickness H w on the road surface and the tire water splash amount M t . The experiment was conducted on a wet road surface and was repeated by changing Hw . H w was obtained from the weight of water on the road surface collected using water absorbing paper, and M t was obtained from the difference in weight of the sponge attached to the mudguard on the rear wheel before and after running.
FIG. 6 shows the relationship between Hw and Mt at running speeds v=20, 40, 60 and 80 km/h. As shown in the figure, the relationship between H w and M t is approximated by H w =aM t 0.45 .
Here, as shown in FIG. 7, the relationship between the function a and the running speed v is such that a decreases as the running speed v increases, and the relationship is expressed by a=0.43exp(-0.007V).
Finally, the relational expression Hw=aMt0.45a=0.43exp(-0.007V) (V: running speed) is obtained.

１ 車輪
２ 塩分濃度センサー
３ 供給流導水スリット
４ 混合部／水はねコレクター
５ 導水板
６ 水はね保護カバー
７ センサー面の水分除去装置
REFERENCE SIGNS LIST 1 wheel 2 salinity sensor 3 feed channel slit 4 mixing section/splash collector 5 water guide plate 6 splash protection cover 7 sensor surface moisture remover

Claims (9)

車両のタイヤが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来るようにした路面の水膜厚測定方法において、車両のタイヤハウス内に塩分濃度センサーを取付け、路面の塩分濃度Cst、およびセンサー部に供給する規定の塩溶液(塩分濃度Csv、質量Mv)とタイヤ水はね量Mtとが混合した塩分濃度Csmixを測定し、塩分濃度がCsvからCsmixへの変化よりタイヤ水はね量Mtを、式M t ＝［（C is― C smix ）／（C smix－ C ts ）］M i を用いて推定し、所定の路面水膜厚さHwとMtの関係式H w ＝ａM t 0.45［a=0.43exp(-0.007V) Ｖは走行速度］を用いて路面水膜厚さHwを求めることを特徴とする路面の水膜厚の測定方法。 In a road surface water film thickness measuring method, water existing on the road surface is splashed up by the rotation of a vehicle tire, thereby measuring the road surface water film thickness Hw (mm). A salinity concentration sensor is installed in the house, and the salinity concentration of the road surface C st , and the salinity concentration obtained by mixing the specified salt solution (salinity concentration C sv , mass M v ) supplied to the sensor and the tire water splash amount M t C smix is measured, and from the change in salinity concentration from C sv to C smix , the tire water splash amount M t is calculated by the formula M t = [(C is - C s mix )/(C s mix - C ts )] Mi , and the road surface water film thickness is estimated using the relational expression Hw = aM t 0.45 [a = 0.43exp (-0.007V) V is the running speed] between the predetermined road surface water film thickness Hw and Mt A method for measuring a water film thickness on a road surface, characterized by obtaining Hw . 車両のタイヤが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来るようにした路面の水膜厚測定装置において、タイヤ後方の泥除け部には塩分濃度センサーが取付けられ、タイヤ泥除け部にはセンサー部を規定の塩溶液(塩分濃度Csv、質量Mv)で濡らしておき、この塩溶液とタイヤ水はね量Mtとが混合した塩分濃度Csmixを測定するために、水はねと上記塩溶液とが混合される混合エリアを設け、路面水膜厚さH w とM t の関係はH w ＝ａM t 0.45［a=0.43exp(-0.007V) Ｖは走行速度］を構成していることを特徴とする路面の水膜厚測定装置。 In the road surface water film thickness measuring device, water on the road surface is splashed up by the rotation of the vehicle tire, and this enables measurement of the road surface water film thickness H w (mm). A salt concentration sensor is attached to the mudguard, and the tire mudguard is wetted with a specified salt solution (salinity concentration C sv , mass M v ). In order to measure the salt concentration C smix mixed with, a mixing area where the water splash and the salt solution are mixed is provided, and the relationship between the road surface water film thickness H w and M t is H w = aM t 0.45 [ a=0.43exp(-0.007V) V is running speed] . 車両のタイヤが回転することで路面に存在する水が跳ね上げられ、これによって路面水膜厚Hw(mm)を測定することが出来るようにした路面の水膜厚測定装置において、タイヤ後方の泥除け部に塩分濃度センサーを取り付け、タイヤ泥除け部にはセンサー部を規定の塩溶液(塩分濃度Csv、質量Mv)で濡らしておき、この塩溶液とタイヤ水はね量Mtとが混合した塩分濃度Csmixを測定するために、塩分濃度センサーに供給流導水スリット、混合部／水はねコレクター、水はね保護カバー、導水板及びセンサ－面の水分除去装置が付加され、規定の塩溶液は車内タンクからポンプによって供給水導水スリットを通して飛散水と供給水とが混合される混合部／水はねコレクターを設け、路面水膜厚さH w とM t の関係はH w ＝ａM t 0.45［a=0.43exp(-0.007V) Ｖは走行速度］を構成していることを特徴とする路面の水膜厚測定装置。 In the road surface water film thickness measuring device, water on the road surface is splashed up by the rotation of the vehicle tire, and this enables measurement of the road surface water film thickness H w (mm). A salt concentration sensor is attached to the mudguard, the tire mudguard is wetted with a specified salt solution (salinity concentration C sv , mass M v ), and this salt solution is mixed with the tire water splash amount M t . In order to measure the salinity C smix , the salinity sensor is supplemented with a feed stream guide slit, a mixing section/splash collector, a splash protection cover, a water guide plate and a moisture removal device on the sensor surface. The salt solution is provided with a mixing section/water splash collector where the splash water and the supply water are mixed through the supply water supply slit by the pump from the in-vehicle tank, and the relationship between the road surface water film thickness H w and M t is H w = aM t 0.45 [a=0.43exp(-0.007V) V is running speed] . 上記飛散水と供給水を混合させる場所を設けた請求項３記載の路面の水膜厚測定装置。 4. The road surface water film thickness measuring apparatus according to claim 3, further comprising a place for mixing the splashed water and the supplied water. 上記飛散水と供給水が混合する場所を塩分濃度センサー上部に設けた請求項３記載の路面の水膜厚測定装置。 4. The road surface water film thickness measuring apparatus according to claim 3 , wherein a place where the splashed water and the supplied water are mixed is provided above the salt concentration sensor. 塩分濃度センサーに飛散水が直接接触しないように水はね保護カバーを設置した請求項３記載の路面の水膜厚測定装置。 4. The road surface water film thickness measuring apparatus according to claim 3 , wherein a water splash protection cover is installed to prevent splashing water from coming into direct contact with the salt concentration sensor. 車に取付けたタンクから供給水を混合部／水はねコレクタ－に導く場合に、水分が損失しないように供給流導水スリットを設けた請求項３記載の路面の水膜厚測定装置。 4. The road surface water film thickness measuring apparatus according to claim 3 , wherein a supply flow guide slit is provided to prevent loss of water when supplying water from a tank attached to a vehicle to the mixing unit/water splash collector. 上記塩分濃度センサーにはセンサ－面の水分除去装置を取り付け、塩分濃度センサーが感知するとその水分が拭き取られるようにした請求項３記載の路面の水膜厚測定装置。 4. The road surface water film thickness measuring apparatus according to claim 3, wherein said salt concentration sensor is attached with a sensor-surface water remover so that the water is wiped off when the salt concentration sensor senses. 塩分濃度測定後に塩分濃度センサー上の水分を除去する水分除去装置は、ワイパーが回転する構造とした請求項８記載の路面の水膜厚測定装置。


9. The road surface water film thickness measuring apparatus according to claim 8, wherein the moisture remover for removing moisture on the salinity concentration sensor after the salinity concentration measurement has a structure in which a wiper rotates.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000241563A (en) 1999-02-17 2000-09-08 Hitachi Cable Ltd Road surface freezing judgment method and device and road surface freezing prediction method and device
JP2007057286A (en) 2005-08-23 2007-03-08 Yuki Center On-vehicle type salt concentration measuring instrument and salt concentration measuring method

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JP2944033B2 (en) * 1995-10-19 1999-08-30 株式会社 拓和 Road surface water sampling device
JP3193324B2 (en) * 1997-06-24 2001-07-30 株式会社 拓和 Road water sampling device
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JP3703062B2 (en) * 1998-03-05 2005-10-05 オムロン株式会社 Road surface condition detection sensor, road surface condition detection device using the same, antifreezing agent spraying vehicle and road patrol car equipped with the sensor

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000241563A (en) 1999-02-17 2000-09-08 Hitachi Cable Ltd Road surface freezing judgment method and device and road surface freezing prediction method and device
JP2007057286A (en) 2005-08-23 2007-03-08 Yuki Center On-vehicle type salt concentration measuring instrument and salt concentration measuring method

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