JPH02309209A - Apparatus for measuring wavy condition of road surface - Google Patents
Apparatus for measuring wavy condition of road surfaceInfo
- Publication number
- JPH02309209A JPH02309209A JP12867289A JP12867289A JPH02309209A JP H02309209 A JPH02309209 A JP H02309209A JP 12867289 A JP12867289 A JP 12867289A JP 12867289 A JP12867289 A JP 12867289A JP H02309209 A JPH02309209 A JP H02309209A
- Authority
- JP
- Japan
- Prior art keywords
- distance
- road surface
- ultrasonic sensor
- ultrasonic
- duct body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002604 ultrasonography Methods 0.000 claims 1
- 238000005259 measurement Methods 0.000 abstract description 3
- 230000010355 oscillation Effects 0.000 description 14
- 239000010426 asphalt Substances 0.000 description 7
- 238000009423 ventilation Methods 0.000 description 4
- 230000003321 amplification Effects 0.000 description 3
- 238000003199 nucleic acid amplification method Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 238000012790 confirmation Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Landscapes
- Road Repair (AREA)
- Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用９寿）
本発明は路面のうねり状態を計１１１ＩＪするための計
測装置に関し、特に、道路の舗装を行うアスファルトフ
ィニッシャ−等に用いられる路面うねり状態計測装置に
関する。DETAILED DESCRIPTION OF THE INVENTION (9 years of industrial application) The present invention relates to a measuring device for measuring a total of 111 IJ of undulations on a road surface, and particularly to a measuring device for measuring undulations on a road surface used in an asphalt finisher for paving roads. Regarding equipment.
（従来の技術）
一般に、アスファルトフィニッシャ−等の敷きならし装
置で道路等の舗装を行う際には予め定められた厚さく設
計値）に実際の舗装厚が維持されているかを確認する必
要がある。この確認に当たっては、実際の舗装厚の舗装
厚をＲＦ測するばかりでなくアスファルトフィニッシャ
−の進行方向の路盤（路面）のうねり状態（路盤凹凸状
態）を計測する必要がある。(Prior art) Generally, when paving roads, etc. with a leveling device such as an asphalt finisher, it is necessary to confirm whether the actual pavement thickness is maintained at a predetermined thickness (design value). be. For this confirmation, it is necessary not only to perform RF measurement of the actual pavement thickness, but also to measure the undulations (roadbed unevenness) of the roadbed (road surface) in the direction of movement of the asphalt finisher.
従来、路盤のうねり状態を計測する際には、光学式セン
サをアスファルトフィニッシャ−に取す付けて、路盤と
光学式センサとの距離を検出しこの距離の変動によって
路盤のうねり状態を求めることが行われている。Conventionally, when measuring the undulation state of the roadbed, it was possible to attach an optical sensor to the asphalt finisher, detect the distance between the roadbed and the optical sensor, and determine the undulation state of the roadbed from changes in this distance. It is being done.
また、同様に超音波センサをアスファルトフィニッシャ
−に取り付けて、超音波センサによって、路盤と超音波
センサとの距離を検出しこの距離の変動によって路盤の
うねり状態を求めることも行われている。Additionally, an ultrasonic sensor is similarly attached to an asphalt finisher, the distance between the roadbed and the ultrasonic sensor is detected by the ultrasonic sensor, and the undulation state of the roadbed is determined from fluctuations in this distance.
（発明が解決しよ、うとする課題）
ところで、上述のように光学式センサを用いた場合、一
般に路盤は光反射率が悪く、さらに、路盤から巻き上が
る粉塵等によって光が遮られる場合があり、その結果、
正確に路盤との距離が計測できず、路盤のうねり状態が
正確に求められないという問題点がある。(Problem to be solved by the invention) By the way, when an optical sensor is used as described above, the roadbed generally has poor light reflectance, and furthermore, the light may be blocked by dust etc. rolled up from the roadbed. ,the result,
There is a problem that the distance to the roadbed cannot be accurately measured and the undulation state of the roadbed cannot be accurately determined.
また、超音波センサを用いた場合には、超音波センサ自
体が周囲の雰囲気、特に、温度、圧力、及び湿度の影響
を受けて音速が変化する。超音波センサの場合、超音波
センサ及び路盤間における超音波の往復時間によって路
盤との距離を求めているから、正確に路盤との距離が計
ＷＪできず、路盤のうねり状態が正確に求められないと
いう問題点がある。Furthermore, when an ultrasonic sensor is used, the speed of sound changes as the ultrasonic sensor itself is influenced by the surrounding atmosphere, particularly temperature, pressure, and humidity. In the case of ultrasonic sensors, the distance to the roadbed is determined by the round trip time of ultrasonic waves between the ultrasonic sensor and the roadbed, so it is not possible to accurately measure the distance to the roadbed, and the undulation state of the roadbed cannot be accurately determined. The problem is that there is no.
本発明の目的は正確に路盤との距離を計測することがで
き、その結果として路盤のうねり状態を正確に求めるこ
とができる路面うねり状態検出装置を提供することにあ
る。An object of the present invention is to provide a road surface undulation state detection device that can accurately measure the distance to the roadbed and, as a result, accurately determine the undulation state of the roadbed.
（課題を解決するための手段）
本発明によれば、路面のうねり状態を計測する際に用い
られ、該路面に面した一端部が開口されたダクト体と、
前記開口部に面した第１の超音波センサと、前記ダクト
体内に設けられた反射板体と、該反射板体に対向して該
反射板体から予め定められた距離離れて前記ダクト体内
に配設された第２の超音波センサと、前記第１及び第２
の超音波センサを駆動するための駆動手段と、前記ダク
ト体内に通風するためのファンと、前記第１及び第２の
超音波センサからの出力を受け、前記第１の超音波セン
サと前記路面との間の第１の距離を超音波が伝搬するの
に要する第１の時間を求めるとともに前記予め定められ
た距離超音波が伝搬するのに要する第２の時間を求め、
前記予め定められた距離、前記第１の時間、及び前記第
２の時間に基づいて前記第１の距離を算出する演算手段
とを有し、該第１の距離に基づいて前記路面のうねり状
態を求めるようにしたことを特徴とする路面うねり状態
計測装置が得られる。(Means for Solving the Problems) According to the present invention, a duct body is used when measuring the undulation state of a road surface and has an open end facing the road surface;
a first ultrasonic sensor facing the opening, a reflector body provided within the duct body, and a first ultrasonic sensor facing the reflector body and located within the duct body at a predetermined distance from the reflector body. a second ultrasonic sensor disposed;
a driving means for driving the ultrasonic sensor; a fan for ventilation in the duct body; Determining a first time required for the ultrasonic wave to propagate a first distance between and determining a second time required for the ultrasonic wave to propagate the predetermined distance;
calculation means for calculating the first distance based on the predetermined distance, the first time, and the second time, and calculating the undulation state of the road surface based on the first distance. A road surface undulation condition measuring device is obtained, which is characterized in that it calculates the following.
（作用）
本発明では、駆動手段で第１及び第２の超音波センサを
駆動する。第１の超音波センサからの超音波は路面で反
射して第１の超音波センサで受信される。一方、第２の
超音波センサからの超音波は反射板体で反射して第２の
超音波センサで受信される。第１及び第２の超音波セン
サからの出力は演算手段に与えられる′。演算手段は第
１の超音波センサから超音波が送出され反射波を受ける
までの時間（第１の時間（１＋ ））を求めるとともに
第２の超音波センサから超音波が送出され反射波を受け
るまでの時間（第２の時間（ｔ２））を求める。第２の
超音波センサと反射板体との距離（Ｌｏ）は予め定めら
れており、演算手段は予め定められた距離（Ｌｏ）、第
１の時間（ｔｌ）、及−び第２の時間（ｔ２）に基づい
て第１の超音波センサから路面までの距離、つまり、第
１の距離（Ｌ）を求める。例えば、
Ｌ−（２Ｌｏ ／１２）／ｌ ＋ ／２によって第１の
距離（Ｌ）を求める。(Operation) In the present invention, the first and second ultrasonic sensors are driven by the driving means. The ultrasonic waves from the first ultrasonic sensor are reflected on the road surface and received by the first ultrasonic sensor. On the other hand, the ultrasonic waves from the second ultrasonic sensor are reflected by the reflection plate and received by the second ultrasonic sensor. Outputs from the first and second ultrasonic sensors are given to arithmetic means. The calculation means calculates the time (first time (1+)) from when the ultrasonic wave is sent out from the first ultrasonic sensor until it receives the reflected wave, and also when the ultrasonic wave is sent out from the second ultrasonic sensor and receives the reflected wave. The time until (second time (t2)) is calculated. The distance (Lo) between the second ultrasonic sensor and the reflection plate body is predetermined, and the calculation means calculates the predetermined distance (Lo), the first time (tl), and the second time. (t2), the distance from the first ultrasonic sensor to the road surface, that is, the first distance (L) is determined. For example, the first distance (L) is determined by L-(2Lo/12)/l + /2.
第１及び第２の超音波センサはダクト体に収納され、し
かもダクト体内はファンによって通風されているから、
第１及び第２の超音波センサは同一の雰囲気中に置かれ
ることになる。The first and second ultrasonic sensors are housed in the duct body, and the inside of the duct body is ventilated by a fan.
The first and second ultrasonic sensors will be placed in the same atmosphere.
このようにして、実質的に第１の超音波センサによる誤
差は第２の超音波センサによって補正されることになる
。In this way, the error caused by the first ultrasonic sensor is substantially corrected by the second ultrasonic sensor.
（実施例） 以下本発明について実施例によって説明する。(Example) The present invention will be explained below with reference to Examples.
第１図を参照して、一端部が開口されたダクト体１１が
開口面を下側にして路面（路盤）の上方に配置されてい
る。ダクト体１１の内壁にはその中央部において左方向
に延びる反射板１２が設けられている。反射板１２の下
側近傍には第１の取付板１３ａが形成されており、反射
板１２に対向して反射板１２の上方には所定の距離をお
いて第２の取付板１３ｂが形成されている。第１の取付
板１３ａ左端には下方に延びる板体１３ｃが取り付けら
れ、第２の取付板１３ｂの左端には下方に延びる板体１
３ｄが取り付けられている。ダクト体１１の上端には通
風口１４ａが形成されており、ファン１４の駆動によっ
て通風口１４ａからダクト体１１に空気が送り込まれる
。Referring to FIG. 1, a duct body 11 having one end opened is placed above a road surface (roadbed) with the opening surface facing downward. A reflecting plate 12 is provided on the inner wall of the duct body 11 at the center thereof and extending to the left. A first mounting plate 13a is formed near the bottom of the reflecting plate 12, and a second mounting plate 13b is formed at a predetermined distance above the reflecting plate 12, facing the reflecting plate 12. ing. A plate body 13c extending downward is attached to the left end of the first mounting plate 13a, and a plate body 13c extending downward is attached to the left end of the second mounting plate 13b.
3d is attached. A ventilation port 14a is formed at the upper end of the duct body 11, and air is sent into the duct body 11 from the ventilation port 14a when the fan 14 is driven.
第１の取付板１３ａには第１の超音波センサ（計ａｌｌ
Ｊ用超音波センサ）１５を構成する発振素子１５ａ及び
受信素子１５ｂが配設され、第２の取付板１３ｂの下面
には第２の超音波センサ（校正用超音波センサ）１６を
構成する発振素子１６ａ及び受信素子１６ｂが配設され
ている。そして、発振素子１６ａ及び受信素子１６ｂと
反射板１２は予め定められた距離（Ｌｏ ）をおいて対
向している。これら発振素子１５ａ及び１６ａは発振増
幅装置１７の発振部に接続され、受信素子１５ｂ及び１
６ｂは発振増幅装置１７の増幅部に接続されている。そ
して、発振増幅装置１はマイクロコンピュータで構成さ
れる制御演算装置１８に接続されている。The first mounting plate 13a has a first ultrasonic sensor (all
An oscillating element 15a and a receiving element 15b constituting the J ultrasonic sensor) 15 are arranged, and the oscillating element 15a constituting the second ultrasonic sensor (calibration ultrasonic sensor) 16 is provided on the lower surface of the second mounting plate 13b. An element 16a and a receiving element 16b are provided. The oscillating element 16a, the receiving element 16b, and the reflecting plate 12 face each other at a predetermined distance (Lo). These oscillation elements 15a and 16a are connected to an oscillation section of an oscillation amplifier 17, and reception elements 15b and 1
6b is connected to the amplification section of the oscillation amplification device 17. The oscillation amplification device 1 is connected to a control calculation device 18 composed of a microcomputer.
路面のうねり状態を計測する際には、制御演算装置１８
から計測指令が発振増幅装置１７に与えられる。これに
よって発振増幅装置１７はスイッチ部１７ａで交互に発
振素子１５ａ及び１６ａを切り替えて発振素子１５ａ及
び１６ａに高周波信号を与える。高周波信号によって発
振素子１５ａ及び１６ａから超音波が送出され、発振素
子１５ａからの超音波（以下第１の超音波という）は路
面１９で反射して反射波（以下第１の反射波という）と
して受信素子１５ｂで受信され、第１の受信信号として
出力される。同様にして、発振素子１６ａからの超音波
（以下第２の超音波という）は反射板１２で反射して反
射波（以下第２の反射波という）として受信素子１６ｂ
で受信され、第２の受信信号として出力される。受信素
子１、５ ｂ及び１６ｂは発振素子１５ａ及び１６ａに
連動して交互に切り替えられ、これによって第１及び第
２の受信信号は発振増幅装置１７で増幅されて、制御演
算装置１８に与えられる。制御演算装置１８は第１の受
信信号を受けると、第１の超音波が発射されてから第１
の反射波を受けるまでの時間（ｔ、）を求める。ここで
、所定の温度、圧力、及び湿度における音速をＶ。とす
ると、第１の超音波センサ１５と路面１９との距離（Ｌ
）は、
Ｌ−（Ｖｏ ｔ １）／２ − （１）で表される。と
ころが、音速ｖ（、は温度（Ｔ）、圧力（Ｐ）、及び湿
度（Ｈ）の関数として、ＶＯｍｆｃＴ、ｐ、Ｈ）で表せ
るから温度（Ｔ）、圧力（Ｐ）、及び湿度（Ｈ）が変化
すると音速Ｖｏが変化してしまい、距離（Ｌ）を正確に
算出することができなくなってしまう。When measuring the undulation state of the road surface, the control calculation device 18
A measurement command is given to the oscillation amplifier 17 from the oscillation amplifier 17 . As a result, the oscillation amplifying device 17 alternately switches between the oscillation elements 15a and 16a using the switch section 17a, and provides high-frequency signals to the oscillation elements 15a and 16a. Ultrasonic waves are sent out from the oscillation elements 15a and 16a in response to a high-frequency signal, and the ultrasonic waves from the oscillation element 15a (hereinafter referred to as first ultrasonic waves) are reflected by the road surface 19 as reflected waves (hereinafter referred to as first reflected waves). It is received by the receiving element 15b and output as a first received signal. Similarly, the ultrasonic waves from the oscillating element 16a (hereinafter referred to as second ultrasonic waves) are reflected by the reflecting plate 12 and are transmitted to the receiving element 16b as reflected waves (hereinafter referred to as second reflected waves).
and output as the second received signal. The receiving elements 1, 5b and 16b are alternately switched in conjunction with the oscillating elements 15a and 16a, whereby the first and second received signals are amplified by the oscillation amplifier 17 and given to the control calculation device 18. . When the control calculation device 18 receives the first reception signal, the control calculation device 18 transmits the first ultrasonic wave after the first ultrasonic wave is emitted.
Find the time (t,) until receiving the reflected wave. Here, the speed of sound at a given temperature, pressure, and humidity is V. Then, the distance between the first ultrasonic sensor 15 and the road surface 19 (L
) is expressed as L-(Vot 1)/2-(1). However, since the sound velocity v (, can be expressed as VOmfcT, p, H) as a function of temperature (T), pressure (P), and humidity (H), temperature (T), pressure (P), and humidity (H) If this changes, the sound speed Vo will change, making it impossible to accurately calculate the distance (L).
ところで、本発明では、制御演算装置１８は第２の受信
信号を受けると、第２の超音波が発射されてから第２の
反射波を受けるまでの時間（ｔ ２ ）を求める。前述
のように第２の超音波センサ１６と反射板１２との距離
は予めり。と定められているから、
Ｌｏ ＝ （Ｖｏ ｔ２）／２ − （２）と表せる
。第（１）式及び第（２）式から距離（Ｌ）は、
Ｌ＝ （２Ｌｏ ／１２）ｔ＋ ／２ 、− （３）で
表される。第（３）式から明らかなように距離（Ｌ）は
音速Ｖ。に依存しなくなる。By the way, in the present invention, upon receiving the second reception signal, the control calculation device 18 determines the time (t 2 ) from when the second ultrasonic wave is emitted until when the second reflected wave is received. As described above, the distance between the second ultrasonic sensor 16 and the reflection plate 12 is determined in advance. Therefore, it can be expressed as Lo = (Vot2)/2 - (2). From equations (1) and (2), the distance (L) is expressed as L=(2Lo/12)t+/2, - (3). As is clear from equation (3), the distance (L) is the speed of sound V. no longer depends on.
制御演算装置１８は第（３）式に基づいて距離（Ｌ）を
求め、算出距離として表示装置１８ａに表示する。The control calculation device 18 calculates the distance (L) based on equation (3) and displays it on the display device 18a as the calculated distance.
距１１ｉ１ （Ｌ）を計測する際には、ファン１４が駆
動され、通風口１４ａから実線矢印で示すように空気が
ダクト体１１内に流入される。この結果、第１及び第２
の超音波センサ１５及び１６は同一の雰囲気（同一の温
度、圧力、及び湿度）に置かれることになる。従って、
ダクト体１１内において音速の相違はなくなる。When measuring the distance 11i1 (L), the fan 14 is driven, and air flows into the duct body 11 from the ventilation opening 14a as shown by the solid arrow. As a result, the first and second
The ultrasonic sensors 15 and 16 will be placed in the same atmosphere (same temperature, pressure, and humidity). Therefore,
There is no difference in sound speed within the duct body 11.
上述のダクト体１１をアスファルトフィニッシャ−に取
り付ければ、アスファルトフィニッシャ−の走行に応じ
て距離（Ｌ）が計測され、これによって、路面１９のう
ねり状態を把握することができる。When the above-described duct body 11 is attached to an asphalt finisher, the distance (L) is measured as the asphalt finisher travels, and thereby the undulation state of the road surface 19 can be grasped.
（発明の効果）
以上説明したように、本発明では超音波センサの配置さ
れた雰囲気に影響されることなく、路面までの距離を計
測することができ、従って、正確に路面までの距離を計
測することができる。この結果、路面のうねり、状態を
正確に把握することができる。(Effects of the Invention) As explained above, in the present invention, the distance to the road surface can be measured without being affected by the atmosphere in which the ultrasonic sensor is placed, and therefore the distance to the road surface can be accurately measured. can do. As a result, it is possible to accurately grasp the undulations and conditions of the road surface.
第１図は本発明による路面うねり状態計測装置の一実施
例を示す図である。
１１・・・ダクト体、１２・・・反射板、１３・・・取
付板、１４・・・ファン、１５・・・第１の超音波セン
サ、１６・・・第２の超音波センサ、１７・・・発振増
幅装置、１８・・・制御演算装置。FIG. 1 is a diagram showing an embodiment of a road surface undulation state measuring device according to the present invention. DESCRIPTION OF SYMBOLS 11... Duct body, 12... Reflection plate, 13... Mounting plate, 14... Fan, 15... First ultrasonic sensor, 16... Second ultrasonic sensor, 17 ...Oscillation amplifier device, 18...Control calculation device.
Claims (1)
に面した一端部が開口されたダクト体と、前記開口部に
面した第１の超音波センサと、前記ダクト体内に設けら
れた反射板体と、該反射板体に対向して該反射板体から
予め定められた距離離れて前記ダクト体内に配設された
第２の超音波センサと、前記第１及び第２の超音波セン
サを駆動するための駆動手段と、前記ダクト体内に通風
するためのファンと、前記第１及び第２の超音波センサ
からの出力を受け、前記第１の超音波センサと前記路面
との間の第１の距離を超音波が伝搬するのに要する第１
の時間を求めるとともに前記予め定められた距離超音波
が伝搬するのに要する第２の時間を求め、前記予め定め
られた距離、前記第１の時間、及び前記第２の時間に基
づいて前記第１の距離を算出する演算手段とを有し、該
第１の距離に基づいて前記路面のうねり状態を求めるよ
うにしたことを特徴とする路面うねり状態計測装置。1. A duct body that is used to measure the undulation state of a road surface and has an opening at one end facing the road surface, a first ultrasonic sensor facing the opening, and a duct body provided within the duct body. a reflection plate body, a second ultrasonic sensor disposed in the duct body opposite to the reflection plate body at a predetermined distance from the reflection plate body, and the first and second ultrasonic waves a drive means for driving the sensor; a fan for circulating air into the duct body; and a drive means for receiving outputs from the first and second ultrasonic sensors, and between the first ultrasonic sensor and the road surface. The first distance required for the ultrasound to propagate the first distance of
and a second time required for the ultrasonic wave to propagate over the predetermined distance, and calculate the second time based on the predetermined distance, the first time, and the second time. 1. A road surface undulation condition measuring device, comprising: arithmetic means for calculating a first distance, and the road surface undulation condition is determined based on the first distance.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12867289A JPH02309209A (en) | 1989-05-24 | 1989-05-24 | Apparatus for measuring wavy condition of road surface |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12867289A JPH02309209A (en) | 1989-05-24 | 1989-05-24 | Apparatus for measuring wavy condition of road surface |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02309209A true JPH02309209A (en) | 1990-12-25 |
Family
ID=14990592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12867289A Pending JPH02309209A (en) | 1989-05-24 | 1989-05-24 | Apparatus for measuring wavy condition of road surface |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02309209A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004246904A (en) * | 2003-02-14 | 2004-09-02 | Microsoft Corp | Electronic stylus and method for judging tip position of stylus |
| US11952730B2 (en) | 2018-08-01 | 2024-04-09 | Sumitomo Construction Machinery Co., Ltd. | Asphalt finisher and management device for road construction machine |
-
1989
- 1989-05-24 JP JP12867289A patent/JPH02309209A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004246904A (en) * | 2003-02-14 | 2004-09-02 | Microsoft Corp | Electronic stylus and method for judging tip position of stylus |
| US9207813B2 (en) | 2003-02-14 | 2015-12-08 | Microsoft Technology Licensing, Llc | Determining the location of the tip of an electronic stylus |
| US11952730B2 (en) | 2018-08-01 | 2024-04-09 | Sumitomo Construction Machinery Co., Ltd. | Asphalt finisher and management device for road construction machine |
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