JP3488699B2 - Road surface slip resistance measuring device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for measuring slip resistance on a road surface, and more particularly to a small device capable of measuring slip resistance on a sidewalk or the like.

[0002]

2. Description of the Related Art There are indoor test equipment and on-site measurement equipment for measuring the slip resistance of a road surface. There are constant extension force method, constant speed method, turntable method, pendulum method, and other special methods (apparatus) in the room, all of which make a road surface sample and measure the friction coefficient of the sample as a point. .

On the other hand, as a field measuring method (apparatus), a deceleration method, a braking stop distance method, a sliding friction resistance direct measuring method, a skid measuring method, a driving force measuring method and the like are known. The on-site measuring device is generally mounted on a vehicle (large bus, automobile, etc.). A small on-site measuring device slides the road surface at high speed and cannot measure snow and ice road surfaces.

[0004]

The problem is that the measurement of the slip resistance on a road surface having a very small slip resistance, for example, a snow and ice road surface,
Although it is extremely important for road barrier-free measures, there is no practical on-site measuring device for snow and ice roads.

The road barrier-free measure here is to measure the skid resistance particularly on a sidewalk (pavement) or a pedestrian crossing, taking into consideration natural conditions including the outside temperature and the condition of snow and ice, and the slope of the sidewalk. Design improvements such as slopes and unevenness of the road surface will be included, and improvement measures to ensure walking safety will be included. Specifically, in cold snowfall areas, there are many fall accidents in winter. A fall accident correlates with the numerical value of the slip resistance on the snow and ice sidewalk, and when the slip resistance falls below approximately 0.25, the number of accidents tends to increase rapidly. More specifically, it is difficult to walk when the slip resistance is 0.2 or less,
When it becomes less than the following, walking becomes difficult, and when it becomes about 0.05, it is in a so-called slippery state, and even a pedestrian who is accustomed to the snow and ice road surface can easily fall if the balance is lost.

The conventional method or apparatus for measuring slip resistance is
Rather than measuring according to the site environment of each sidewalk, it is a method for collecting general academic data,
The reality is that there is no method or device for specifically considering and implementing road barrier-free measures.

For example, even in the field measurement method, the conventional technique often has a drawback that the traction force and the rotation of the wheel are precisely controlled and measured, and the operation is complicated and the apparatus cost is increased. For example, it is the invention described in JP-A-07-063658 and JP-A 06-286630. In addition, a vehicle-mounted measuring device cannot measure a pedestrian-only sidewalk or a pedestrian-designed road surface.

Therefore, an object of the present invention is to measure the slip resistance of a pedestrian-only sidewalk or pedestrian crossing on site, and specifically improve the sidewalk design based on the data. Of course, the device cost is reduced as much as possible.

[0009]

In order to achieve the above object, a road surface slip resistance measuring device according to the present invention comprises a bogie that can be towed by human power and wheels that rotate as the bogie moves. It is equipped with a reference wheel that does not put on and a measuring wheel that rotates with the movement of the dolly and can apply a braking load.The reference wheel and the measuring wheel are arranged in the front and rear positions of the dolly, while A counter device for measuring the number of revolutions and a counter device for measuring the number of revolutions of the measuring wheel are provided, and a means for recording the braking load of the measuring wheel is provided, and the rotational difference between the reference wheel and the measuring wheel and the braking load of the measuring wheel are provided. Based on, the slip resistance of the road surface is calculated.

The means for recording the braking load of the measuring wheel may be composed of a load cell and a sensor device for measuring the inclination angle of the road surface. Further, the truck may be configured to include a temperature sensor that measures the road surface temperature in a non-contact manner and a displacement sensor that measures the inclination angle of the truck.

[0011]

1 to 3 show an embodiment of a road surface slip resistance measuring apparatus according to the present invention. The road surface slip resistance measuring device according to the present invention measures the resistance value based on the rotation difference of the wheels that are rotated by traction due to human power. Therefore, the mechanical structure part and the electronic structure part based on the sensor measurement are used. With and.

First, referring to FIGS. 1 and 2, the part having a mechanical structure will be described. The slip resistance measuring apparatus according to the present invention comprises a carriage 10 which can be pulled by human power. Dolly 1
0 is equipped with a box-shaped main body case 11 formed of a panel material such as metal, and two rear wheels 12 and 13 arranged at left and right rear portions of the main body case 11, and can be steered in front of the main body case 11. The front wheels 14 are arranged in the. Reference numeral 15 is a movable hood arranged so as to be swingable (rotatable) with respect to the main body case 11, and 16 is the movable hood 15.
It is a connecting plate that connects the front wheel 14 and the front wheel 14. Since the front wheel 14 is connected to the movable hood 15 via the connecting plate 16, the front wheel 14 can freely change its direction when the pulling direction changes.

Inside the body case 11, a measuring wheel 20 and a reference wheel 30 are arranged at the front and rear. In order to ensure the accuracy of measurement, the measurement wheel 20 and the reference wheel 30 have the same diameter,
It is desirable to set the diameter larger than that of the front wheels 14 and the rear wheels 12, 13. This is because the larger the wheels (20, 30) are, the more subtle rotation errors can be detected. On the other hand, since the front wheels 14 and the rear wheels 12 and 13 do not affect the measured values of the rotational speed, relatively small wheels (tires) may be used to reduce the weight.

The measuring wheel 20 and the reference wheel 30 are arranged on the same straight line so as to move back and forth. This is so that the measurement wheel 20 and the reference wheel 30 move on the same track as much as possible. Further, if the measurement wheel 20 and the reference wheel 30 are arranged so as to be displaced to the left and right, the balance of the trolley 10 becomes unbalanced and the burden of the towing work increases. In terms of balance, the front wheel 14, the measurement wheel 20, the reference wheel 30
It is desirable to arrange the vehicles on the same straight line at the center of the carriage.

In principle, either of the front and rear positions of the measuring wheel 20 and the reference wheel 30 may be front or rear, but considering the snowfall situation at the site, the measuring wheel 20 is set to the front and the reference wheel 30 is set to the rear. It is desirable to place it in

The measuring wheel 20 is provided with a weight (weight for load cell) 22 of, for example, about 30 kg in order to apply a braking load for resistance measurement. Therefore, when the measuring wheel 20 is arranged in the front, the measuring wheel 20 in front of the trolley can efficiently compact the snowfall on the road surface, and the subsequent movement of the reference wheel 30 can be made smooth.

In FIG. 2, reference numeral 26 is a measuring wheel 2.
A side plate 36 for supporting a 0 axle (not shown),
It is a side plate for supporting the axle 35 of the reference wheel 30.

Next, the sensors (electronic structure) of the slip resistance measuring device according to the present invention will be described. The arrangement of the sensors is illustrated in FIG. The minimum required sensor device for realizing the slip resistance measuring device according to the present invention is a rotary encoder 27 that measures the rotation speed of the measuring wheel 20, a load cell 28 that controls the braking load of the measuring wheel 20, and a reference wheel 30. A rotary encoder 37 for measuring the number of revolutions,
It is a tilt angle sensor (displacement sensor) 51 that measures the tilt angle of the road surface. It is also desirable to mount a temperature sensor 52 for measuring the temperature of the road surface (ice and snow temperature).

These sensor / control system devices are arranged in the most rational place for measurement. For example, the rotary encoder 27 and the load cell 28 are preferably near the measuring wheel 20, and the rotary encoder 37 is preferably near the measuring wheel 30. Further, the tilt angle sensor (displacement sensor) 51 is preferably located at the front of the body case 11. This is because the angle change caused by the road inclination can be detected most sensitively. Temperature sensor 52
When a non-contact optical measuring device is adopted, it is arranged on the lower surface of the main body case 11. This is to detect the radiation temperature of snow and ice on the road without contact.

FIG. 3 illustrates an apparatus configuration for calculating and recording the measurement result based on the measurement value of each sensor. In principle, the measurement of the slip resistance of the road surface includes the rotary encoder 27 that measures the number of revolutions of the measurement wheel 20, and the reference wheel 3
This is performed based on the difference in the number of revolutions with the rotary encoder 37 that measures the number of revolutions of zero. Reference numeral 61 is a rotation difference calculation unit that detects a rotation difference.

The rotation difference between the measurement wheel 20 and the reference wheel 30 is due to the braking load applied to the measurement wheel 20. The higher the braking load, the larger the rotation difference. Therefore, the braking amount applied to the measuring wheel 20 based on the weight 22 is obtained from the load cell 28 and used as a calculation factor of the slip resistance value.

Further, the braking amount by the weight 22 is measured by the measuring wheel 20.
The force that acts on (vertical force) changes depending on the inclination angle of the road surface. Therefore, the inclination angle of the road surface obtained from the inclination angle sensor 51 is also a factor for calculating the slip resistance value.

Reference numeral 65 is a calculation of the slip resistance of the road surface based on the above calculation elements, that is, the numerical value calculated by the rotation difference calculation unit 61, the braking amount obtained from the load cell 28, and the inclination angle of the road surface obtained from the inclination angle sensor 51. This is a slip resistance calculation unit. Although the numerical value of the calculation result may differ depending on the setting of the coefficient and the way of constructing the arithmetic expression, the calculated value has the same meaning contents as long as the same coefficient / the same expression is used.

Although FIG. 3 shows the temperature sensor 52 for detecting the surface temperature of the road surface in addition to various sensors, even if the calculated value of the slip resistance is the same, the meaning and content differ depending on the road surface temperature. Since there are many cases, the road surface temperature is saved and recorded in the data storage unit 68 that finally saves the data so as to contribute to the analysis at a later date.

Therefore, according to such a slip resistance measuring device, the slip resistance value of the road surface can be measured on site with a device configuration that can be mounted on the carriage 10 that can be pulled by human power. The on-site measurement according to the present invention is carried out with a comprehensive balance of quickness and easiness of measurement while respecting the precision of measured values.

Therefore, by using the cart 10 that can be towed by human power, it is possible to measure the slip resistance of a pedestrian crosswalk or the pedestrian side walk which cannot be measured by the conventional device. Due to advances in sensor technology, the accuracy of rotation speed error detection, tilt angle detection, and braking load detection accuracy has increased significantly in recent years, and is comparable to conventional slip resistance measurement devices that require expensive equipment configurations. It is possible to obtain a precision without.

The slip resistance measuring device according to the present invention is not limited to the embodiment described above. For example, dolly (1
0) shape and rear wheels (12, 13) to be placed on the trolley (10)
You can increase the number of. Further, the braking load on the measuring wheel 20 is not limited to the use of the weight 22, and, for example, a hydraulic brake device may be used. This is because the slip resistance value can be easily calculated if the braking amount is known.

The sensors arranged on the carriage (10) are
It is not limited to the above description. For example, an outdoor air temperature sensor, a light amount sensor for measuring the amount of solar radiation, a timer device for recording the measurement time, a GPS device for accurately specifying the position of the measurement site, an altimeter, a hygrometer, etc. are appropriately selected and arranged. Of course, it can be used for data analysis and data processing at a later date.

[0029]

As described above, according to the slip resistance measuring apparatus of the present invention, it is possible to measure the slip resistance of a pedestrian-only sidewalk or pedestrian crossing on site.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a side view of the configuration of a measuring apparatus according to the present invention.

FIG. 2 is a diagram exemplifying a configuration of a measuring apparatus according to the present invention from a plane.

FIG. 3 is a diagram illustrating a data processing configuration of sensors according to the present invention.

[Explanation of symbols]

10 carts 11 body case 12, 13 rear wheels 14 front wheels 15 movable hood 16 contact plate 20 measuring wheels 30 reference wheels 22 Weight (weight for load cell) 26, 36 Side plate 35 axles 27,37 Rotary encoder 28 load cell 51 Tilt angle sensor (displacement sensor) 52 Temperature sensor 61 Rotation difference calculation unit 65 Slip resistance calculator 68 Data storage

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-4-102034 (JP, A) JP-A-4-2946 (JP, A) JP-A-63-193036 (JP, A) JP-A-2001-183250 (JP, A) JP 2001-50889 (JP, A) JP 2002-131217 (JP, A) Actually opened 61-12034 (JP, U) Actually opened 63-146752 (JP, U) US Patent 2700297 (US, A) US Patent 3367170 (US, A) UK Patent Application Publication 1229959 (GB, A) (58) Fields searched (Int.Cl. ⁷ , DB name) G01N 19/02 E01C 23/01 G01L 5 / 00

Claims (3)

(57) [Claims] 1. A trolley that can be towed by human power, a reference wheel that rotates with the movement of the trolley and does not apply a braking load, and a wheel that rotates with the movement of the trolley to apply the braking load. Equipped with a measuring wheel capable of controlling, the reference wheel and the measuring wheel are arranged in front of and behind the bogie, and a counter device for measuring the rotational speed of the reference wheel and a counter device for measuring the rotational speed of the measuring wheel are provided and A slip resistance measuring device for a road surface, which is provided with means for recording a braking load of a wheel, and calculates a slip resistance of the road surface based on a rotation difference between a reference wheel and a measuring wheel and a braking load of the measuring wheel. 2. The road surface slip resistance measuring device according to claim 1, wherein the means for recording the braking load of the measuring wheel comprises a load cell and a sensor device for measuring the inclination angle of the road surface. 3. The slippage of a road surface according to claim 1, wherein the bogie includes a temperature sensor for measuring a road surface temperature in a non-contact manner and a displacement sensor for measuring an inclination angle of the bogie. Resistance measuring device.