JPH11326539A - Road surface state-measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously and accurately detect the state of a driving road surface by discriminating the road surface state based on a detection result according to the detection means of a friction state and a conductive state with a road surface. SOLUTION: Before measurement, for example, a tractor joint 11 is connected and at the same time a power cord is connected, thus setting up an operation- enable state. When a road to be measured is reached, a controller 50 and a recording part start to be operated. When an operation is made so that a driving speed becomes constant, the large part of weight such as a frame 10 is supported by a joint 11 and a tire 12, and a wheel 20 is lightly pressed against the road surface due to the energization force of a spring 31. The impedance of the driving road surface is detected via wheels 20a and 20b being rotated on the road surface during driving, and a slide rate is calculated according to the fluctuation of the rotation state of the wheel 20b due to the energization force being detected by a load cell 33. A road state value being set to a corresponding section is read by a microprocessor where the impedance and the slide rate are inputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road surface condition measuring device for continuously detecting the condition of a running road surface while traveling to accurately grasp the condition of the road surface. The present invention relates to a road surface condition measuring device for accurately grasping.

[0002]

2. Description of the Related Art Conventionally, a device for measuring road surface conditions includes a device for detecting frozen road surface at a fixed point (Japanese Patent Publication No. 5-56831).
JP-A-5-127378) and a device that detects a road surface temperature by performing continuous measurement while traveling on a road mounted on a traveling vehicle or towed by the traveling vehicle (Japanese Patent Application Laid-Open No. 52-127378). JP-A-62-272176), one that detects reflected light (JP-A-2-95243),
Detecting images (Japanese Patent Application Laid-Open No. 8-327540)
Etc. are known.

[0003] An automatic braking device (A
Assuming the existence of BS), to estimate the coefficient of friction required for its operation, the automatic brake device is operated in conjunction with the operation of the automatic brake device or periodically, and the tire slip rate and other vehicle behavior at that time Is also known that detects road conditions intermittently to judge the road surface state (Japanese Patent Laid-Open No. Hei.
No. 70).

[0004]

However, in such a conventional road surface condition measuring apparatus, apart from the method of detecting a fixed point, in continuous measurement while running, the detection method is limited or complicated, and sufficient measurement is required. Results are not always obtained.
Depending on the unevenness of the traveling road surface, the detection may be interrupted, or the detection may be performed, but the corresponding state may not be able to be determined due to a plurality of states. For this reason, it is not easy to continuously and accurately grasp the dry state and the frozen state of the road surface. For example, in order to determine whether or not the road surface is dry based on electric resistance or the like, heating and thawing or the like is also performed in order to distinguish from a frozen state (Japanese Patent Laid-Open No. 52-127378). While difficult to do.

[0005] Further, even if the road surface condition is determined based on a tire slip ratio or the like suitable for measurement during traveling (Japanese Patent Laid-Open No. 5-270370), the tire slip ratio is determined by whether the road surface is dry. After the determination as to whether or not to perform the determination is based on other physical quantities, the determination is merely used as a determination material for further subdivision. In other words, only when the road surface is below the freezing point, go one step further,
The tire slip ratio is only used to determine whether the road surface at that time is in a frozen state or a snow-covered state. That is, the magnitude of the tire slip rate does not affect the determination of whether the road surface is dry. For this reason, the judgment result is greatly influenced by other preferential physical quantities. However, it is not always easy to realize an appropriate physical quantity, detection element selection, and installation thereof.

However, when spraying salt on the road surface to prevent snow melting and freezing, it is often desired to accurately detect the road surface condition. If the amount of spraying is small, the original purpose of spraying cannot be achieved. Conversely, if the spraying is excessive, undesired results such as salt damage may be caused. For this reason, the condition of the road surface,
It is necessary to accurately determine whether or not the road surface is dry. Further, since the road surface to be measured is a long road existing everywhere, such as a general road or an expressway, it is important to provide a road surface condition measuring device at low cost.

Therefore, it is a technical problem to continuously measure the road surface condition while traveling on the road surface and to accurately grasp the road surface condition. The present invention has been made to solve such a problem, and an object of the present invention is to realize a road surface condition measuring device capable of continuously and accurately detecting the state of a traveling road surface.

[0008]

Means for Solving the Problems First to ninth means invented to solve such problems are described below.
The configuration and operation and effect will be described below.

[First Solution] A road surface condition measuring device according to a first solution (as described in claim 1 at the beginning of the application) detects a condition of the road surface while traveling on the road surface. In the state measuring device, first detecting means for detecting a frictional state with the road surface, second detecting means for detecting a conductive state of the road surface, and based on a result of these detections (preferably a dry state and another state And a determination means for determining the road surface condition of the road surface by using both detection results in the classification).

Here, the above-mentioned "state of friction with the road surface"
It means a physical quantity related to the frictional characteristics between the road surface and the rolling member or the like in contact with the road surface, and as a specific example, it is desirable to use a slip amount described later.
A general coefficient of friction also applies. Further, the “conductive state of the road surface” means a physical quantity related to the electrical conduction characteristics of the road surface, and includes, for example, electric resistance, impedance, admittance, etc. between two points on the road surface. Further, sheet resistance across multiple points on a road surface and the like also apply.

[0011] In the road surface condition measuring device of the first solving means, when detecting the condition of the traveling road surface, the frictional state with the road surface is detected and the electric conduction state of the road surface is also detected. Then, the road surface state is determined based on these detection results. That is, instead of giving priority to only one of the detection results, using both detection results together,
A determination process is performed based on the combination. As a result, it is possible to clearly distinguish between the dry state and the other states, which have been difficult to determine conventionally. At least, the accuracy of the determination is improved. Therefore, according to the present invention, it is possible to realize a road surface state measuring device capable of continuously and accurately detecting the state of a traveling road surface.

[Second Solution] The road condition measuring device of the second solution (as described in claim 2 at the beginning of the application) is the road condition measuring device of the first solution. , Wheels provided to be biased toward the road surface.

[0013] In the road surface condition measuring device of the second solution, the wheels are pressed against the road surface even when the vehicle is traveling on a rough road surface, so that the wheels always contact the road surface. maintain. Therefore, continuous measurement can be reliably performed by using the wheels for detecting physical quantities that require contact with the road surface even during traveling, such as the state of friction with the road surface.

[Third Solution] The road condition measuring device according to the third solution (as described in claim 3 at the beginning of the application) is the road condition measuring device according to the second solution. A third detecting means for detecting the urging force of the wheel, and a braking means for suppressing the rotation of the wheel.

In the road surface condition measuring device according to the third aspect of the present invention, the wheels following the running road surface are prevented from slipping when the rotation thereof is suppressed by the braking device. Based on this, the amount of slip is calculated or the coefficient of friction is estimated to detect the friction state of the road surface, and the wheel urging force at that time is also detected in parallel. The state of friction with the road surface is affected not only by the state of the road surface but also by the contact pressure between the wheels and the road surface, and so the use of a wheel biasing force corresponding to the contact pressure eliminates or reduces the effect. As a result, it is possible to obtain a physical quantity close to the physical quantity of only the road surface state. Therefore, according to the present invention, it is possible to realize a road surface state measuring device capable of continuously and accurately detecting the state of the traveling road surface by more accurately grasping the friction state.

[Fourth Solution] The road condition measuring device of the fourth solution (as described in claim 4 at the beginning of the application) is the road condition measuring device of the third solution. Means for detecting the rotation state of the wheel, wherein the first detection means obtains a friction state with the road surface based on the rotation state of the wheel, and the braking means repeats the braking force. It is characterized by being changed.

In the road surface condition measuring device according to the fourth solution, the braking force applied to the wheels changes repeatedly, and the rotation state of the wheels changes accordingly. Then, the rotation state is detected, and the friction state is detected based on the detected value. This allows
A wide range of frictional states is properly detected based on the situation when a change in the braking force on the wheels rolling on the road surface causes a change in the rotational state. In particular, by combining not only the repetitive change of the braking force but also the change width and level of the braking force in accordance with the biasing force, a wide range can be obtained without causing a strong impact or a change in the traveling speed. The friction state can be detected over the range.

[Fifth Solution Means] The road surface condition measuring device of the fifth solution means (as described in claim 5 at the beginning of the application) is the road surface condition measurement device of the second to fourth solution means. In the wheel, a contact portion with the road surface has conductivity.

In the road surface condition measuring device according to the fifth aspect of the present invention, power can be supplied to the traveling road surface through the wheels, so that the frictional state with the road surface can be detected using the wheels, and the wheels can be detected. The conductive state of the road surface is also detected by using. Thus, the detection member can be shared by the first detection unit and the second detection unit.

[Sixth Solution Means] The road surface condition measuring device of the sixth solution means (as described in claim 6 at the beginning of the application) is the road surface condition measurement device of the fifth solution means. The second detecting means outputs an alternating current to the road surface via the wheels.

In the road surface condition measuring device according to the sixth aspect of the present invention, even if an unknown current such as a stray current has already flowed on the road surface, a discrimination process based on the modulation frequency can be easily performed. Most components other than the same frequency components as the alternating current are removed, and only the output alternating current is almost detected. Accordingly, when detecting the conductive state of the road surface, it is possible to accurately detect the conductive state of the road surface while avoiding an undesired effect of the existing current flowing on the road surface.

[Seventh Solution Means] The road surface condition measuring device of the seventh solution means (as described in claim 7 at the beginning of the application) is the road surface condition measurement device of the fifth and sixth solution means. Wherein three or more wheels are provided.

In the road surface condition measuring device according to the seventh aspect, at least a pair of wheels must be connected to the road surface to detect the conductive state of the road surface. While it must be in contact, even if some of the three or more wheels jump off the road,
By using an appropriate pair selected from the remaining wheels, energization can be continued and continued. further,
In the case of four or more, the sheet resistance can be measured. This makes it possible to more reliably detect the conductive state of the road surface.

[Eighth Solution] The road condition measuring device of the eighth solution (as described in claim 8 at the beginning of the application) is the road condition measuring device of the first to seventh solutions. And a positioning means such as a GPS (global positioning system).

In the road surface condition measuring device according to the eighth aspect, since the current traveling position is known, the road surface condition measurement data such as the detection result and the discrimination result are correlated with the position information to perform data processing or the like. Management can be performed. Accordingly, when using the road surface condition measurement data at another time or another device, the process can be performed while selecting and extracting appropriate data from a large amount of data based on the position information. In addition, the accuracy of measurement can be improved by using known data to change the content of determination by learning.

[Ninth Solution Means] The road surface condition measuring device of the ninth solution means (as described in claim 9 at the beginning of the application) is the road surface condition measurement device of the first to eighth solution means. And a transmission means (such as a wireless device).

In the road surface condition measuring device according to the ninth solving means, the measurement result of the road surface condition is transmitted in real time as needed. As a result, road surface information such as a freezing warning can be displayed quickly and accurately. Even if the spraying device that sprays salt or the like to prevent freezing is not integrated with the road surface condition measuring device, the measurement result of the road surface condition should be received from the road surface condition measuring device and sprayed by using this. Thus, the spraying amount can always be kept properly.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the road surface condition measuring apparatus of the present invention achieved by such a solution will be described with reference to the following first to fifth embodiments.
The first embodiment embodies the above-described first to sixth solving means, the second embodiment is a modification thereof, and the third embodiment also embodies the above-mentioned seventh solving means. The fourth embodiment also embodies the eighth and ninth solving means described above.

The road surface condition measuring device for detecting the road surface condition while traveling on the road is divided into a self-propelled type capable of self-propelled driving and a non-self-propelled type driven by towing or pushing. The third, fifth and fifth embodiments are of the traction type, and the second and fourth embodiments are of the self-propelled type. Furthermore, from the viewpoint of spraying a spraying agent such as a deicing agent or a snow melting agent based on the road surface conditions obtained by measurement, it is also integrated with a spraying device and directly linked, or separate from the spraying device And indirectly cooperate, but it is divided into an online type system that sends measurement data of the road surface condition to the spraying device in real time, an offline type system that cooperates with the spraying device by handing over the recording medium after the measurement is completed,
The first embodiment is of an offline type, and the fourth embodiment is of an online type.

[0030]

First Embodiment A first embodiment of a road condition measuring apparatus according to the present invention will be described with reference to the drawings. FIG. 1 schematically shows the mechanical structure, in which (a) is a plan view and (b) is a side view. Also, FIG.
(A) is a block diagram of the whole control system, (b)
Are the determination tables.

The road surface condition measuring device (see FIG. 1) includes, with respect to the frame 10, a joint 11 connected to a preceding towing vehicle or the like in order to be towed and travel on the road surface.
A pair of left and right tires 12 that bear the weight of the frame 10 and the like by being rotatably supported and rolling on the road surface
Are provided. Further, the frame 10 is provided with a drip-proof box 13 for accommodating a brake unit 40 and a controller 50 described later. Furthermore, in order to mount a wheel 20 for measuring a road surface condition and a suspension unit 30 added thereto, which will also be described later,
A downwardly extending hinge 14, an upwardly extending arm 15 and a post 16 for supporting the same are also provided. These 13
16 are similarly provided at two places on the left and right of the frame 10.

The wheels 20 are provided to detect the friction state with the road surface and the conductive state of the road surface while traveling. A pair of wheels 20 on the left and right sides can be used for both types of detection.
a and 20b are arranged, and in order to make the contact portion with the road surface conductive, a rubber tire located at the outermost periphery is mixed with a large amount of carbon powder or metal powder,
Good conductor fibers are also used.
The conductive portions of the wheels 20a and 20b are electrically connected to the controller 50 via sliding contacts (not shown).

Each of the wheels 20a and 20b has an axle 21 that is electrically insulated from the conductive portion rotatably mounted on the tip of a brace 23 via a bearing 22 and a base of the brace 23. The end is pivotally supported by the hinge 14, and the arm 20 swings so that the wheel 20 can freely move up and down within a predetermined range. The arm 23
Between the middle part of the arm and the arm 15
Is interposed. The suspension unit 30 generates a tension force against the compression, and the spring 31 for urging the wheel 20 by pushing the arm 23 toward a lower road surface with the tension force.
And a damper 32 that narrows the flow of air and oil accompanying the advance and retreat of a rod provided by being freely inserted into the spring 31 to reduce sudden expansion and contraction of the spring 31, and detects a force acting on the spring 31 and the damper 32. The load cells 33 are sequentially connected. Thus, in addition to the means for urging the wheel 20 toward the road surface, a third detecting means for detecting the urging force is also provided.

One axle 24 of the axles 21 of the wheels 20
Is provided with a pulley 25 for detecting the rotational speed of the wheel 20b and applying a brake. Further, the brake unit 40 is mounted on the box 13. The brake unit 40 includes an electromagnetic brake 41 that generates a braking force, and a joint 42 that eliminates runout.
, The pulley 43 and the encoder 44 connected to the output shaft of the electromagnetic brake 41, and the pulley 43 and the pulley 2
5 and a belt 45 that is stretched. Then, the braking force from the electromagnetic brake 41 is transmitted to the wheel 20b via the joint 42, the pulley 43, the belt 45, the pulley 25, and the axle 24 in this order. The rotation of the wheel 20b is transmitted to the detection rotation shaft of the encoder 44 via the axle 24, the pulley 25, and the belt 45. Thus, in addition to the braking means for applying a braking force to the wheel 20 to suppress its rotation, a means for detecting the rotational state of the wheel 20 is also provided.

The electromagnetic brake 41 may have a clutch that simply turns on and off the generated braking force in accordance with a control signal. In this example, the braking force can be set independently for each of the on and off times. , Which can be changed as appropriate. Thus, the brake unit 40 can change the braking force applied to the wheels 20 with the passage of time, and at the same time, can appropriately change the level of the braking force and the like.

The controller 50 (see FIG. 2A)
The above-described operating members 20, 41 and detecting members 20, 33, 4
Peripheral circuits 51 to 51 electrically connected directly to
54, a microprocessor (MPU) 55 that collects control and detection data via these and performs arithmetic processing based on the collected data, and a recording unit 57 that records the arithmetic result. The operation is performed by supplying electric power from a towing vehicle or the like together with the brake unit 40. The peripheral circuits 51 to 54 include a current drive circuit 51 and a current detection circuit 52 for detecting electric resistance (a conductive state of the road surface) of the road surface, and a slip ratio of the wheel 20 with respect to the road surface (the state of friction with the road surface). ) Is roughly divided into a braking signal generation circuit 53 and a slip rate detection circuit 54 for detecting the slippage.

The current drive circuit 51 applies a voltage V of, for example, 1000 Hz different from the frequency of the commercial power to one of the wheels 20a.
The current detection circuit 52 measures the current I flowing through the wheel 20a, the road surface, and the other wheel 20b according to the voltage V, and at that time outputs the output voltage V by the band-pass filter. 1000Hz which is the modulation frequency of
Only the preceding and succeeding components are extracted as the current I, and the ratio between the voltage V and the current I is calculated and an appropriate correction calculation is also performed to obtain the impedance R corresponding to the electric resistance of the road surface.
Is calculated. The obtained impedance R is sent to the microprocessor 55 as needed. Thus, the second detecting means for detecting the electrical resistance between two points, that is, the impedance R as the conductive state of the road surface while outputting the alternating current to the road surface via the wheels is provided.

The braking signal generation circuit 53 includes the electromagnetic brake 4
In order to change the braking force generated in step 1 on and off, a rectangular pulse signal D having a duty ratio of about 50% is generated, and this pulse signal D is transmitted to the electromagnetic brake 41 as a control signal. Then, the braking force is transmitted from the electromagnetic brake 41 to the wheels 20b via the pulleys 43 and the like to suppress the rotation of the wheels 20b, but the magnitude changes according to the pulse signal D. Since the frequency of the pulse signal D is restricted by the responsiveness based on the inertia and the like of the wheel 20b, the frequency is set to about several Hz or less, for example, 2 Hz. Thus, the first detecting means for repeatedly changing the braking force applied to the wheels is provided.

The braking signal generation circuit 53 receives the urging force F detected by the load cell 33, and increases or decreases the ON value of the pulse signal D in accordance with the increase or decrease of the urging force F. Also, a process of increasing or decreasing the off value is performed. More specifically, the pulse signal D is turned on by a linear operation expression (D = a × F + b) using the parameters a and b by an experiment or the like, another nonlinear expression, an approximation function with a broken line, a step function, or the like. A value is calculated. The off value of the pulse signal D is
The ON value is determined by multiplying the ON value by a positive number less than “1” or by reducing a predetermined value. It should be noted that these parameters a and b and the function form are such that, for any value of the biasing force F, the braking force that causes no slip on a dry road surface, but causes the slip on a somewhat wet road surface. The range of
It is preferable that the pulse signal D is set so as to cover the pulse signal D.
Thereby, in addition to the repetitive change of the braking force, the first detecting means also changes the change width and level of the braking force according to the urging force.

The slip ratio detection circuit 54 receives the rotational speed N detected by the encoder 44 and calculates a slip ratio β.
This is sent to the microprocessor 55.
That is, when the wheel 20b slips on the road surface due to the braking force of the brake unit 40, the rotation speed N
Changes periodically in response to the on / off of the pulse signal D, the rate of change is calculated from the periodic waveform change of the rotation speed N. Further, the slip rate β is calculated by performing a correction operation on the fluctuation rate based on the urging force F and the on / off value of the pulse signal D. In the correction calculation, in situations where the braking force is strong and slipping is likely to occur,
In a situation where the slip rate β is corrected to be smaller for the same fluctuation rate, and conversely, in a situation where the braking force is weak and slipping hardly occurs, the slip rate β is corrected to be larger for the same fluctuation rate. Thereby, the first detecting means detects the slip ratio β of the wheel 20b in each cycle of the pulse signal D as a friction state with the road surface based on the change in the rotation speed of the wheel 20b.

A judgment table 56 is stored in the memory of the microprocessor 55, and the microprocessor 55 operates the slip ratio detecting circuit 5 for each cycle of the pulse signal D.
Each time the slip ratio β is received from No. 4, the determination table 56 is searched by the program processing using the slip ratio β and the impedance R at that time. Then, the road surface state P obtained by the search is sent to the recording unit 57 and recorded on a recording medium such as a magnetic tape or an MO. Thus, a determination means for determining the road surface state based on the detection result of the friction state β with the road surface and the conductive state R of the road surface is provided.

The judgment table 56 (see FIG. 2B)
In addition to being classified according to whether the slip ratio β is smaller or larger than a predetermined threshold value, it is also classified according to whether the impedance R is large, medium, or small. Have been. Then, only the section in which the slip ratio β is small and the impedance R is large, which is a category for a case in which the wheel does not slip or hardly slips and also corresponds to a state in which current does not flow or extremely hard to flow, It is set to a dry state. This section is different from the section set in the sherbet state and the like, and is not specified only by the slip ratio β. Even the impedance R alone cannot be specified. Thereby, when determining the road surface condition,
A dry state and another state such as a frozen state are separated based on a combination of both the slip ratio and the electric resistance.

The manner of use and operation of the thus constructed road surface condition measuring device of the first embodiment will be described.

Prior to the measurement, the joint 11
And connect the power cord, etc., and set it up in an operable state. Then, when the leading towing vehicle is driven to reach the road to be measured or the like, the operation of the controller 50 is started, and the operation of the recording unit 57 is also started. Then, the road etc., 4 per hour
Travel at 0-50 km. At that time, drive carefully so that the traveling speed is constant.

Then, most of the weight of the frame 10 and the like is supported by the joint 11 and the tire 12, and the wheel 20 is lightly pressed against the road surface by a relatively small urging force generated by the spring 31. As described above, since the wheels 20 that do not need to bear a large weight need only be light and have a small inertia, they can follow the road surface even with a small urging force. In addition, the impact generated on the wheels 20 due to the unevenness of the road surface is reduced by the presence of the damper 32 without substantially impairing the following ability. Therefore, even if the strength of the tire portion is reduced to some extent due to conductivity, the life of the tire portion does not need to be reduced so much, and the cost required for measurement can be saved in the long term.

During the traveling, the current drive circuit 51 and the current detection circuit 52 detect the impedance R of the traveling road surface every moment via the wheels 20a and 20b rolling on the road surface. Is taken in at any time. At the same time, the urging force F detected by the load cell 33 is input to the braking signal generation circuit 53, and based on this, a pulse signal D whose on value and off value are adjusted is generated, and the electromagnetic brake 41 Sent to

Further, according to the braking force, the wheels 20
b changes, and the rotation speed N of the
4 is detected. At this time, even if the urging force F changes, the braking force also changes in accordance with the fluctuation, so that the rotation speed N periodically changes almost certainly except when the road surface does not absolutely slip. The rotation speed N is determined by the slip rate detection circuit 5.
4, the slip rate β is calculated based on the fluctuation and the like, and is also taken into the microprocessor 55. This is performed periodically in synchronization with the pulse of the pulse signal D. Thus, the impedance R and the slip ratio β are continuously obtained at a predetermined cycle.

When the impedance R and the slip ratio β are obtained, the microprocessor 55 searches the determination table 56 using them. Then, the road surface state value set in the corresponding section is read. That is, one of “dry state”, “frozen state”, “sherbet state”, “wet state”, and “water film state” is selected according to the magnitude of the slip ratio β and the magnitude of the impedance R. Is done. In this manner, the road surface state is determined continuously based on the friction state between the traveling road surface and the detected road surface and the conductive state of the road surface at a predetermined cycle. Then, the road surface state P is sent to the recording unit 57 and recorded on a recording medium.

The data recorded on the recording medium is read out after the completion of the measurement, and is used for statistical processing for grasping the road condition, and is an important judgment material when spraying salt or the like with a spray truck. However, instead of or together with the recording unit 57,
A spraying device that inputs the road surface condition P as needed and varies the spraying amount in accordance with the input may be mounted on the frame 10 or the like.

[0050]

Second Embodiment A road surface condition measuring device according to a second embodiment, which is schematically shown in a side view in FIG. 3, is different from the device according to the first embodiment in that a pair of wheels 20 are disposed not in the left and right but in the front and rear. And that the main body such as the frame 10 is attached to the chassis of the measuring vehicle 60 and is directly supported. Thus, the road surface condition measuring device can travel on its own without being towed.

[0051]

Third Embodiment A road surface condition measuring apparatus according to the third embodiment, which is shown in FIG. 4 in two plan views, is different from the apparatus according to the first embodiment in that a large number of wheels 20 are provided. Is a point.

First, in FIG. 4A, a third wheel 20c is provided as the wheel 20 in addition to the wheels 20a and 20b described above. Further, the functions of the current drive circuit 51 and the current detection circuit 52 are such that the impedance R is selectively determined by using one of the pair of the wheel 20a and the wheel 20b or the pair of the wheel 20a and the wheel 20c. It has been extended to detect. The selection is switched when the detection value becomes almost infinite.

In this case, when the wheels 20a and 20b are selected and the wheels 20b jump off the road surface,
Since the impedance R detected using the wheels 20a and 20b becomes infinite, the wheels 20a and 20c are selected, and the detection of the impedance R is continued using these. Also, if the wheel 20c jumps off the road surface during the detection, the impedance R detected using the wheels 20a, 20c becomes infinite, so that the wheels 20a, 2c are again detected.
0b is selected and the impedance R
Detection continues. Thus, even if one of the wheels 20b, 20c moves away from the road surface, the detection of the impedance R is continued using the remaining wheels that are in contact with the road surface.

Next, in FIG. 4B, the fourth wheel 20d is also added, and when all the wheels 20a to 20d are in contact with the road surface, the sheet resistance of the road surface is measured. When one of the wheels leaves the road surface, the resistance between the two points by the wheels 20a and 20b and the wheels 20c and 20c
The effective one which is not infinite among the two-point resistance by d is adopted. In this way, energization of the road surface is maintained as much as possible, and the conductive state of the road surface is detected more reliably.

[0055]

Fourth Embodiment A road surface condition measuring device according to a fourth embodiment, whose block diagram is shown in FIG. 5 (a), is different from the devices according to the first and second embodiments in that positioning is performed on a measuring vehicle 60. The point is that a means and a transmission means are additionally provided. In addition, FIG.
FIG. 2 shows a block diagram of a spraying vehicle that runs after the measuring vehicle shown in FIG.

The measuring vehicle 60 has a GPS as a positioning means.
A GPS antenna 61 that receives a signal from a satellite for use, and a GPS receiver 62 that receives the signal and determines the current position are provided. In addition, as the transmission means, the radio 6
4 and a wireless antenna 65 connected thereto. Further, the position information is input from the GPS receiver 62, the road surface state P is input from the controller 50, and each time the road surface state P is input, the road surface state P and the position information at that time are paired with the radio 64. There is also provided a transmission data processing device 63 for transmitting data via the transmission line.

On the other hand, a spraying truck 70 equipped with a spraying device 71
Is also provided with a spray control device 80 for variably controlling the spray amount of the spray device 71. The dispersion control device 80 includes, as receiving means, a receiving wireless antenna 81 corresponding to the wireless antenna 65, a receiving circuit 82 that receives the road surface state P and the position information from the wireless device 64 using the receiving antenna 81,
A buffer memory 83 for temporarily storing the road surface state P and the position information in a sequential first-in first-out manner is provided. Further, a GPS antenna 85 for receiving a signal from a GPS satellite and a GPS receiver 86 for receiving the signal to determine a current position are provided as positioning means.

Further, the spraying control device 80 is also provided with a spraying control signal generating circuit 84 composed of a microprocessor or the like. The spraying control signal generating circuit 84 receives position information from the GPS receiver 85 as needed. The data is input, the current position is compared with the position information of the leading data in the buffer memory 83, and when the positions match, the leading data is taken out from the buffer memory 83, and according to the road surface state value. , Change the value of the spray control signal. The spraying control signal is sent to the spraying device 71, and the spraying device 71 adjusts the spraying amount accordingly.

In this case, using the spraying device 71, the measuring vehicle 60 is run ahead of the road on which the salt 72 is to be sprayed, and the spraying vehicle 70 is also run later. Then, the road surface state P measured by the road surface condition measuring device of the measuring vehicle 60 is
From the spraying vehicle 70 to the spraying control device 80,
It is temporarily stored in the buffer memory 83. Then, data corresponding to the current position of the sprayer 70 is stored in the buffer memory 83.
And the spraying amount of the spraying device 71 is adjusted by the spraying control signal generation circuit 84. In this way, even if the measuring vehicle 60 and the spreading vehicle 70 travel without regard to each other's position, and even if the distance between the two vehicles fluctuates, the spraying amount of the salt 72 is always based on the respective running positions. It is adjusted to be appropriate.

[0060]

Fifth Embodiment The road surface condition measuring device of the fifth embodiment shown in FIG. 6 differs from the device of the first embodiment in that a camera 91 for photographing a predetermined range of the road surface and a camera 91 for photographing the photographing range are provided. A laser transmitter 92 that performs spot illumination substantially toward the center,
A radiation thermometer 93 that measures the surface temperature of the road surface in a non-contact manner is also
It is a point provided. Another difference is that the determination table 56 and the determination method are extended. FIG.
(A) is a schematic diagram of a main part of an additional member,
(B) to (d) are examples of captured images, and (e) is an example of a determination table.

If the road surface is dry, a dark spot narrowed down at the center of the image appears in the image obtained by photographing the spot obliquely irradiated by the laser transmitter 92 with the camera 91 (FIG. 6B). See), if fresh snow is piled up on the road,
The point image is displaced from the center of the image as the wheels cut into the fresh snow (see FIG. 6C). This displacement amount is substantially proportional to the vehicle height based on the surface of fresh snow. In addition, when ice is formed on the road surface, the laser light is diffused, and the point image is blurred (see FIG. 6D). Furthermore, there is also a tendency that the reflectance increases if snow is piled up not only in fresh snow but also in compact snow. Then, by processing an image having such characteristics, the vehicle height, the reflectance, and the diffusivity are also detected. The radiation thermometer 93 detects whether the road surface temperature is below freezing.

In this case, in addition to the basic physical quantities, the impedance R and the slip ratio β, the vehicle height, the reflectance, the diffusivity, and the road surface temperature are obtained as auxiliary physical quantities. The determination table 56 (see FIG. 6E) is divided into rows, one road surface state is assigned to each row (see the rightmost column in FIG. 6E), and the other columns are ,
Each of the above physical quantities is assigned to each. further,
In the element of each row and each column, a discrimination value of each physical quantity that most matches the road surface state of the corresponding row is set for each column. In addition,
Although illustration is omitted, corresponding to this determination table 56,
For each element of each row and column, there is also provided a weighting coefficient table in which the degree to which the physical quantity of the corresponding column contributes to the determination of the road surface state of the corresponding row is set as a coefficient value.

When the microprocessor 55 searches the judgment table 56, each physical quantity is first classified into appropriate large and small, high, medium and low, and then the physical quantity in each column is matched for each row of the judgment table 56. The coefficient values in the corresponding weight coefficient table are added up for the element that has been set. Finally, the row with the largest value is selected, and the road surface state value set for that row is determined as the road surface state P at that time. In this way, a detailed and more reliable continuous measurement of the road surface condition is performed.

[0064]

As is apparent from the above description, in the road surface condition measuring device according to the first aspect of the present invention, the state of the traveling road surface is based on both the frictional state and the conductive state and not on one of them. By making the determination, there is an advantageous effect that a road surface state measuring device capable of continuously and accurately detecting the state of the traveling road surface can be realized.

Further, in the road surface condition measuring device according to the second solution of the present invention, continuous measurement of the road surface condition can be reliably performed by making the wheels follow the traveling road surface. This has the advantageous effect of:

Further, in the road surface condition measuring device according to the third solving means of the present invention, the influence of the contact pressure on the frictional state with the road surface is removed and reduced by using the urging force of the wheel. This has an advantageous effect that the state of the traveling road surface can be detected more accurately.

Further, in the road surface condition measuring device according to the fourth solution of the present invention, a wide range of conditions can be obtained based on the situation when a change in the braking force on the wheels rolling on the road surface causes a change in the rotation condition. There is an advantageous effect that the friction state can be appropriately detected.

Further, in the road surface condition measuring device according to the fifth solution of the present invention, the sharing of members can be improved by using the wheels for detecting the frictional condition for detecting the conductive state. This has the advantageous effect of being able to do so.

Further, in the road surface condition measuring device according to the sixth aspect of the present invention, the current is conducted so as to be able to discriminate the frequency. There is an advantageous effect that the state can be accurately detected.

Further, in the road surface condition measuring device according to the seventh solution of the present invention, even if some of the wheels jump off the road surface, the energized state is maintained. Has the advantageous effect of being able to reliably detect.

In the road condition measuring apparatus according to the eighth aspect of the present invention, since the road condition measurement data can be used in association with the position information, a large amount of data can be appropriately processed. This has the advantageous effect that it has become possible to do so.

Further, in the road surface condition measuring device of the ninth solution means of the present invention, the measurement result of the road surface condition is transmitted at any time, so that the quick display of the road surface information and the separation of the spraying device can be achieved. This has the advantageous effect that it has become possible.

[Brief description of the drawings]

FIG. 1 is a plan view (a) and a side view (b) showing the mechanical structure of a first embodiment of a road surface condition measuring device of the present invention.

FIG. 2 is a control block diagram (a) and a determination table (b).

FIG. 3 is a schematic side view of a second embodiment of the present invention.

FIG. 4 is a main part plan view of a third embodiment of the present invention.

FIG. 5 is a block diagram of a fourth embodiment of a road surface condition measuring apparatus according to the present invention and a diagram for explaining a use situation;
Is a measuring vehicle, and (b) is a spraying vehicle.

6 (a) is a schematic diagram of a main part, FIGS. 6 (b) to 6 (d) are photographed image examples, and FIG. 6 (e) is a determination table in a fifth embodiment of the road surface condition measuring apparatus of the present invention. is there.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Frame (frame part, support part, inspection vehicle, traveling vehicle, moving body) 11 Joint (joint, connection part, locking part, detachable part, towing part) 12 Tire (follower wheel, support wheel) 13 Box (protection) Box, drip-proof cover, storage unit) 14 hinge (shaft support, support) 15 arm (shaft support, support) 16 post (support, support) 20 wheels (running wheel, rolling wheel, measuring wheel, detection member, 1st, 2nd detection means) 20a, 20b, 20c, 20d Wheel 21 Axle (wheel support member) 22 Bearing (wheel support member) 23 Crosspiece (wheel support member) 24 Axle (wheel support member, braking means, first detection) Means) 25 Pulley (rotary transmission member, braking means, first detecting means) 30 Suspension part (suspension part, urging means) 31 Spring (elastic member, elastic member, urging means) 32 Damper (buffer member, urging means) Means) 33 Load cell (load meter, third detecting means) 40 Brake unit (braking means, first detecting means) 41 Electromagnetic brake (braking force generation source, braking means) 42 Joint (rotary joint, connecting portion, transmission member, braking means) 43 Pulley (rotational transmission member, braking unit, first detection unit) 44 Encoder (rotational speed detection unit, first detection unit) 45 Belt (rotational transmission member, braking unit, first detection unit) 50 Controller (control device, electronic circuit) Part, detecting means, discriminating means) 51 current driving circuit (ground resistance detecting circuit, second detecting means) 52 current detecting circuit (ground resistance detecting circuit, second detecting means) 53 braking signal generating circuit (braking force control means, braking) means,
(First detecting means) 54 Slip rate detecting circuit (slip rate calculating section, friction state detecting means, first detecting means) 55 Microprocessor (calculating means, determining means) 56 Determination table (determining means) 57 Recording section 60 Measurement vehicle (measuring section) Self-propelled vehicle) 61 GPS antenna (positioning means) 62 GPS receiver (positioning means) 63 transmission data processing device 64 wireless device (transmitting device, transmitting device) 65 wireless antenna (transmitting device) 70 spraying vehicle 71 spraying device 72 salt ( 80 spraying control device 81 wireless antenna 82 receiving circuit 83 buffer memory 84 spraying control signal generating circuit 85 GPS antenna 86 GPS receiver 91 camera (imaging device) 92 laser transmitter 93 radiation thermometer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshinao Mame 2-16-46 Minami Kamata, Ota-ku, Tokyo Inside Tokimec Co., Ltd. (72) Inventor Hiroaki Seo 2--16-46 Minami Kamata, Ota-ku, Tokyo No. In the company Tokimec

Claims (9)

[Claims] 1. A road surface condition measuring device for detecting a condition of the road surface while traveling on the road surface, a first detecting means for detecting a frictional state with the road surface, and a second detecting means for detecting a conductive state of the road surface. A road surface condition measuring device comprising: a detecting device; and a determining device that determines a road surface condition of the road surface based on the detection results. 2. The road surface condition measuring device according to claim 1, further comprising wheels urged toward the road surface. 3. The road surface condition measuring device according to claim 2, further comprising third detecting means for detecting the urging force of said wheel, and braking means for suppressing rotation of said wheel. 4. The vehicle according to claim 1, further comprising means for detecting a rotation state of the wheel, wherein the first detection means obtains a friction state with the road surface based on the rotation state of the wheel. The road surface condition measuring device according to claim 3, wherein the braking force is repeatedly changed. 5. The road surface condition measuring device according to claim 2, wherein the wheel has a conductive portion at a contact portion with the road surface. 6. The road surface condition measuring device according to claim 5, wherein said second detecting means outputs an alternating current to said road surface via said wheels. 7. The road surface condition measuring device according to claim 5, wherein three or more wheels are provided. 8. The road surface condition measuring device according to claim 1, further comprising positioning means. 9. The road surface condition measuring device according to claim 1, further comprising a transmitting unit.