JPH0821714A - Road-surface shape measuring device - Google Patents

Abstract

PURPOSE:To provide a device for measuring road-surface shape, which can be miniaturized and weight of which can be reduced and in which operators can be decreased, in the road-surface shape measuring device being loaded on a car or being installed on the shoulder of a road or the outside of a roadway and measuring the shapes of the irregularities, slope, etc., of a road surface in a noncontact manner. CONSTITUTION:An inclinometer 12 detecting the angle of inclination of a frame 11 fixed onto a measuring car 10 and a rotary driving section 13 generating a rotary motion in an approximately vertical surface 10 while outputting a signal regarding the angle of rotation are mounted. A distance measuring section 14 measuring a distance from a road surface while being turned by the rotary motion from the rotary driving section 13 and a processor obtaining a vertical distance and a horizontal distance from the road-surface shape measuring device to the road surface by using a distance measured value acquired by the distance measuring section 14, the angle of inclination of the frame detected by the inclinometer 12 and the angle of rotation output from the rotary driving section 13 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road surface shape measuring device which is mounted on a vehicle or installed on a road shoulder or outside a roadway and which measures the shape of road surface irregularities, slopes and the like in a non-contact manner.

[0002]

2. Description of the Related Art A conventional road surface shape measuring device is shown in FIG.
There is one shown in. In the figure, reference numeral 1 is a main frame, and the main frame 1 has a width corresponding to a measured width of a road surface, and both ends thereof are supported by wheels 5. A traveling carriage 2 is slidably attached to the lower side of the main frame 1 along the longitudinal direction of the main frame 1, and a measuring unit 4 is fixed to the traveling carriage 2. The main frame 1 measures the road surface shape while being pulled by the vehicle in a direction orthogonal to the longitudinal direction of the main frame 1 and moving on the road surface.

When measuring the road surface shape, the traveling vehicle 2 is moved along the longitudinal direction of the main frame 1 (in the direction of the arrow in the figure) by a drive source such as a motor (not shown), and the measuring unit 4 moves while moving. And the distance between the road and the road.
FIG. 10 shows the measurement principle of the measuring unit 4. The measuring unit 4 includes a laser light emitting element 6, a light projecting lens 7, a light receiving lens 8 and a CCD.
The laser light from the laser light emitting element 6 is applied to the road surface through the light projecting lens 7, and a part of the scattered reflected wave from the road surface is condensed by the light receiving lens 8 to provide the CCD element 9 To reach. The position of the CCD element that receives the light changes according to the change in the distance between the road surface and the measurement unit 4. For example, in the figure, when the road surface changes from the road surface RS1 to the road surface RS2, the light receiving position of the CCD element 9 changes from 9a to 9b. That is, the distance to the road surface is known from the position of the CCD element 9 that receives the laser light, and the unevenness of the road surface is obtained by finding the distance each time the traveling carriage 2 moves along the longitudinal direction of the main frame 1. You can

[0004]

However, in such a conventional road surface shape measuring apparatus, when the measurement width of the road surface shape is, for example, 3 m, the length of the main frame 1 becomes long corresponding to this measurement width. There is a problem. Therefore, the traveling carriage mechanism and the drive mechanism are large in size, and because the traveling accuracy is required for a long stroke, not only the price becomes expensive, but also the weight is disadvantageous, and it is difficult to move and operate at a measurement site. There is also the problem of requiring a large number of people.

Further, it is possible to make the frame expandable and contractible by making it into a telescopic frame structure so that the measuring width can be made longer than that of the frame in the minimum contracted state, but the mechanism becomes complicated, and similarly, it is heavy and expensive. I have a problem. The present invention has been made in view of the above problems, and an object of the present invention is to provide a road surface shape measuring apparatus which can be downsized and reduced in weight, and can be reduced in manpower.

[0006]

In order to achieve the above object, a road surface profile measuring apparatus according to claim 1 of the present invention generates a turning motion in a substantially vertical plane and outputs a signal relating to the turning angle. A rotation drive unit that outputs, an inclinometer that detects the inclination angle of the rotation drive unit, a distance measurement unit that measures the distance to the road surface while rotating by the rotation movement from the rotation drive unit, and a distance measurement And a processing device for obtaining the vertical distance and the horizontal distance from the road surface shape measuring device to the road surface using the distance measurement value obtained by the section, the tilt angle detected by the inclinometer, and the turning angle output from the turning drive unit. Prepare This road surface shape measuring device can be mounted on a vehicle. According to a second aspect of the present invention, there is provided a level measuring device, a level, a rotary drive unit that generates a rotary motion in a substantially vertical plane, and outputs a signal related to the rotary angle, and a rotary drive. A road surface shape is measured using a distance measurement unit that measures the distance to the road surface while rotating by the rotation movement from the unit, and the distance measurement value obtained by the distance measurement unit and the rotation angle output from the rotation drive unit. A processing device for determining a vertical distance and a horizontal distance from the device to the road surface is provided. This road surface shape measuring device can be installed on the road shoulder or outside the road.

The distance measuring unit may be, for example, a light wave distance meter that measures a distance by irradiating a light wave toward a road surface and receiving a reflected wave thereof. The rotation drive unit may include a pulse motor that generates a rotation movement and a pulse motor drive circuit that drives the pulse motor, and the pulse motor drive circuit may be configured to output a signal regarding a rotation angle.

The rotary drive unit converts the rotary motion from the pulse motor for generating rotary motion into a reciprocating linear motion, and further translates the reciprocating linear motion into a predetermined point of the road surface shape measuring apparatus. It has a transmission mechanism for converting into a rotational movement in a substantially vertical plane which is the center of rotation, and a pulse motor drive circuit for driving a pulse motor, and the pulse motor drive circuit can output a signal relating to a rotation angle. .

[0009]

According to the first aspect of the invention, the distance measuring section is rotated in a substantially vertical plane by the rotational movement generated by the rotational drive section. For example, if the tilt angle of the rotation drive unit detected from the inclinometer from the horizontal plane is θ ₀ , and the rotation angle of the rotation drive unit from the reference axis is θ ₁ , the distance measurement unit deviates from the vertical axis. The angle θ is

[0010]

## EQU1 ## θ = θ ₀ + θ ₁ . The distance measurement value obtained by the distance measuring unit using the argument θ is converted into a vertical distance and a horizontal distance from the road surface shape measuring device to the road surface. By obtaining these distances at a plurality of measurement points that traverse the road surface while rotating the distance measuring unit, a cross-sectional road surface cross-sectional view showing unevenness of the road surface can be obtained.
By rotating the distance measuring unit, the size of the entire road surface shape measuring device can be made sufficiently smaller than the measurement width of the road surface shape,
Weight can be reduced. According to the second aspect of the invention, the distance measuring section is rotated substantially in the vertical plane by the rotational movement generated by the rotational drive section. For example, if the rotation angle of the rotation drive unit from the reference axis is θ ₁ and the rotation drive unit is installed horizontally with a level, the deviation angle θ of the distance measurement unit from the vertical axis is

## EQU2 ## θ = θ ₁ . The distance measurement value obtained by the distance measuring unit using the argument θ is converted into a vertical distance and a horizontal distance from the road surface shape measuring device to the road surface. By obtaining these distances at a plurality of measurement points that traverse the road surface while rotating the distance measuring unit, a cross-sectional road surface cross-sectional view showing unevenness of the road surface can be obtained.
By rotating the distance measuring unit, the size of the entire road surface shape measuring device can be made sufficiently smaller than the measurement width of the road surface shape,
Weight can be reduced.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a configuration of a road surface shape measuring apparatus of the present invention. The road surface shape measuring apparatus of this embodiment is a measuring vehicle 1
It is installed in 0. In the figure, reference numeral 11 denotes a frame fixed to the measurement vehicle 10, which is supported by an on / offline carriage 15 as necessary, and its position on a horizontal plane (XY plane) and a rotation angle around a vertical axis (Z axis) are adjusted. To be done.

An inclinometer 12 is provided on the frame 11 to detect and output an inclination angle from the horizontal plane in the longitudinal direction of the frame 11.
Is installed and the rotation drive unit 13 is fixed to the frame 11. The rotary drive unit 13 includes a drive motor that generates a rotary motion and an angle transmitter 29 such as a potentiometer or an encoder that detects and outputs the rotary angle of the rotary output shaft 13a. The output from the angle transmitter 29 is supplied to the processing device 16 described later and fed back to the drive motor to perform known servo control. The inclinometer 12 may be directly attached to a fixed part such as a housing of the rotation drive part 13 fixed to the frame 11 to directly detect the inclination angle of the rotation drive part 13.

The rotation output shaft 13a of the rotation drive unit 13 has
The distance measuring unit 14 is attached. The frame 11,
It is desirable that the rotation drive unit 13 and the distance measurement unit 14 be attached to each other in advance before fixing the frame 11 to the measurement vehicle 10 and adjusted to obtain accuracy. Distance measuring unit 1
4 is provided with a light wave range finder 19 (FIG. 3) that emits a light wave toward the road surface, for example. The optical distance meter 19 is reciprocally rotated right and left in a substantially vertical plane by the rotation drive unit 13 so that its optical axis crosses the road surface. As shown in FIG. 2, the signal from the lightwave distance meter 19 is supplied to the rotation driving unit 13
The signals from the angle transmitter 29 and the inclinometer 12 are transmitted to the processing device 16 mounted on the measurement vehicle 10. The processing device 16 is connected to the display device 17, and the power supply device 18
Is mounted on the measurement vehicle 10 and supplies electric power to the rotation drive unit 13, the optical distance meter 19, and the like.

The processing device 16 further includes a time measuring unit 25,
The measurement distance calculation unit 26 and the road surface unevenness calculation unit 27 are provided (see FIG. 3), the measurement distance calculation unit 26 calculates the measurement distance from the lightwave distance meter 19, and the road surface unevenness calculation unit 27 drives the inclinometer 12 and the rotation drive. The output of the angle transmitter 29 of the unit 13 is received and converted into information about the unevenness of the road surface. FIG. 3 shows a lightwave rangefinder 1
The light wave range finder 19 includes a laser light emitting element 20, a light projecting lens 21, a light receiving lens 23, and a laser light receiving element 24. The laser light emitting element 20 emits laser pulse light at predetermined time intervals, and the light projecting lens 21 turns the light into parallel light and irradiates the road surface RS.
Part of the reflected light from the road surface RS is condensed by the light receiving lens 23 and reaches the laser light receiving element 24. In the time measuring unit 25 of the processing device 16, the time interval between the transmission signal serving as the trigger signal to the laser light emitting element 20 and the light receiving signal from the laser light receiving element 24 is counted at the clock frequency, and the count number is measured. The distance calculation unit 26 converts the distance into a distance and obtains the measured distance l. The measured distance 1 is sent to the road surface unevenness calculation unit 27 and the processing described below is performed.

FIG. 4 is an explanatory view for explaining the operation of this device. Reference numeral 30 is a rotation center point of the distance measuring unit 14. Three
Reference numeral 1 is a conceptual line representing only the longitudinal direction of the frame 11, and the inclinometer 12 obtains the inclination angle θ _{0 of the} frame 11 in the longitudinal direction, in other words, from the horizontal plane of the fixed portion of the rotary drive unit 13. Rotation output shaft 1 of the rotation drive unit 13
The distance measuring unit 14 attached to the 3a has a rotation center point 3
A vertical line 32 which is a reference line of the rotation drive unit 13 with 0 as the center
Rotate left and right around the center line. The rotation angle θ ₁ from the vertical line 32 is output from the angle transmitter 29. The deviation angle θ of the optical axis of the distance measuring unit 14 from the vertical axis 33 is

[0016]

## EQU3 ## It is obtained by θ = θ ₁ + θ ₀ . When the distance from the rotation center point 30 to the measurement reference point 34 of the distance measuring unit 14 is R and the measurement distance is 1,
The height from the rotation center point 30 to the road surface at the measurement point, that is, the vertical distance H, and the horizontal distance L from the rotation center point 30 to the road surface at the measurement point are calculated by the following equations.

[0017]

Equation 4] H = (R + l) cosθ = (R + l) cos (θ 1 + θ 0) L = (R + l) sinθ = (R + l) sin (θ 1 + θ 0) Therefore, the uneven road surface calculating section 27, a known value And the measured distance 1 output from the measured distance calculation unit 26, the output θ ₀ from the inclinometer 12, and the output θ ₁ from the angle transmitter 29 of the rotation drive unit 13 to perform the above calculation. By that,
Find H and L. The vertical distance H and the horizontal distance L to this measurement point are sent to the display device 17 and plotted.

FIG. 5 shows an example of the measurement results.
The maximum scanning rotation angle is 51.34 °, and the measurement width of 5 m is taken from it. The unit of the distance is mm, and the vertical distance H and the horizontal distance L to the measurement point are obtained and plotted for each measurement point with the rotation center point 30 as a reference. In this way, by rotating the distance measuring unit 14 by the rotation driving unit 13 and measuring the unevenness of the road surface, downsizing and weight reduction can be achieved, which leads to lower cost and labor saving. You can measure.

FIG. 6 shows another embodiment of the rotary drive unit.
The rotation drive unit 40 of the present embodiment uses a pulse motor 41 as a drive motor and omits the angle transmitter 29. That is, the distance measuring unit 14 is attached to the output shaft 41a of the pulse motor 41 via the attachment plate 41b, and the pulse distribution circuit 42 and the micro step driver 43, which is a pulse motor drive circuit, are provided, and the pulse motor 41 is provided at predetermined angles. To drive.

Since the resolution is high, an arbitrary stepping operation can be performed, and the road surface unevenness calculating section 27 can obtain a signal corresponding to the rotation angle θ ₁ of the distance measuring section 14 from the microstep driver 43. it can. FIG. 7 further shows another embodiment of the rotary drive unit. The rotary drive unit 50 of the present embodiment uses the pulse motor 51 as a drive motor, omits the angle transmitter 29, and at the same time, makes the step drive of the pulse motor 51 a uniform scan of the horizontal distance of the measurement surface. It is configured in. That is, the pulse motor 51 is fixed to the frame 11 so that the output shaft of the pulse motor 51 is rotatably arranged in parallel with the longitudinal direction of the frame 11, and the output shaft of the pulse motor 51 has a ball screw portion 5.
2 are attached integrally. A mounting plate 56 is slidably supported by a linear guide plate 55 rotatably mounted via a bearing 54 to a shaft 53a extending in a direction substantially perpendicular to the ball screw portion 52 from a nut portion 53 screwed with the ball screw portion 52. To be done. The upper end of the mounting plate 56 is rotatably supported by the frame 11 via a bearing 57. Then, the distance measuring unit 14 is fixed to the mounting plate 56. These, ball screw part 5
2, the nut portion 53, the bearing 54, the linear guide plate 55, the mounting plate 56, and the bearing 57, the transmission that converts the rotational movement from the pulse motor 51 into rotational movement with the rotational center point 30 as the rotational center. It constitutes the mechanism.

According to this structure, the ball screw 52 is rotated by the rotation of the pulse motor 51, and the nut portion 53 is moved in parallel with the longitudinal direction of the frame 11. Mounting plate 56
Has an upper end rotatably attached to the frame 11 and is slidably supported by a linear guide plate 55 that moves in parallel with the longitudinal direction of the frame 11 together with the nut portion 53. It is possible to reciprocally rotate about the rotation center point 30.

As shown in FIG. 8, the turning step of the pulse motor 51 corresponds to the displacement points 60, 60 ... Since light is emitted in the direction connecting the displacement points 60, 60, ..., The measurement step intervals in the horizontal direction on the measurement surface can be made substantially uniform. Road surface unevenness calculation unit 27
Is a distance measuring unit 1 from a pulse motor drive circuit (not shown).
A signal corresponding to the rotation angle θ _{1 of} 4 is obtained.

It is possible to use a pinion and a rack instead of the ball screw portion 52 and the nut portion 53.
Next, FIG. 11 is a perspective view showing a configuration of a road surface shape measuring apparatus according to another embodiment of the present invention. The road surface shape measuring apparatus according to the present embodiment is installed on a road shoulder or outside the road ER. In the figure, 11-1 is a frame installed on the road shoulder or outside the road ER, which is an elevator tripod here.

A rotary drive unit 13 similar to that of the first embodiment is fixed to the upper flat surface of the frame 11-1, and a distance measuring unit 14 is attached to the rotary output shaft 13a. A level 62 is directly attached to the housing of the rotation drive unit 13. The level 62 may be directly attached to the frame 11-1. Further, although not shown, the rotation drive unit 13 may include an angle transmitter 29 that detects and outputs the rotation angle of the rotation output shaft 13a, and the distance measurement unit 14 may include the optical distance meter 19. Similarly, the outputs from the angle transmitter 29 and the optical distance meter 19 are supplied to the processing device. Similar to the first embodiment, the processing device includes a time measuring unit, a measurement distance calculating unit, and a road surface unevenness calculating unit. The measurement distance calculating unit calculates the measurement distance from the lightwave range finder 19 of the distance measuring unit to obtain the road surface unevenness. Angle transmitter 2 of the rotation drive unit in the calculation unit
It receives the output of 9 and converts it into information about the unevenness of the road surface.
The processing device is connected to the display device 17, a power supply device (not shown) is connected, and the rotation drive unit 13 and the lightwave distance meter 19 are connected.
Power is supplied.

To explain the operation of this device, in the device installed on the road shoulder or outside the road ER, the casing of the rotary drive unit 13 and the upper horizontal part of the frame 11-1 are preliminarily adjusted horizontally by the level 62. To be done. As shown in FIG. 11, the distance measuring unit 14 attached to the rotation output shaft 13 a of the rotation driving unit 13 has the rotation center point 30 as the center and the rotation driving unit 13.
With the vertical line 32, which is the reference line, as the origin, the turning motion is performed in the range of θ _1MAX to θ _1MIN toward the road RD direction. The rotation angle θ ₁ from the vertical line 32 becomes the deviation angle θ from the vertical axis 33 of the optical axis of the distance measuring unit 14 (θ = θ ₁ ) and is output from the angle transmitter 29. As in the previous embodiment, if the distance from the rotation center point 30 to the measurement reference point 34 of the distance measuring unit 14 is R and the measurement distance is l, the height from the rotation center point 30 to the road surface of the measurement point, that is, The vertical distance H and the horizontal distance L from the rotation center point 30 to the road surface at the measurement point are calculated by the following equations.

[0026]

## EQU5 ## H = (R + 1) cos θ ₁ L = (R + 1) sin θ ₁ Therefore, in the road surface unevenness calculation unit, R which is a known value, the measurement distance 1 output from the measurement distance calculation unit, and the rotation drive unit 1
By using the output θ ₁ from the angle transmitter 29 of _No. 3, H and L are obtained. The vertical distance H and the horizontal distance L to this measurement point are sent to the display device 17 and plotted.

FIG. 12 shows an example of the measurement result. The scanning rotation angle range is from θ _1MIN = 18.4 ° to θ _1MAX =
It is set to 59.0 ° and the measuring width of 4 m is taken from it. The unit of distance is mm, and each measurement point is the center of rotation 3
Vertical distance H and horizontal distance L to the measurement point with 0 as the reference
Is sought and plotted. In this way, the size of the entire road surface shape measuring device can be made small and low in weight as in the previous embodiment, and since it is installed on the road shoulder and outside the roadway, it is necessary to regulate the roadway. Absent. Therefore, it is possible to save manpower, cost, and time required for road regulation, to avoid traffic congestion due to the regulation, to eliminate work on a dangerous road, and to improve safety.

FIG. 13 shows an example in which the entire road surface shape measuring device shown in FIG. 11 is mounted on a self-propelled carriage or a hand-pushed carriage 70. The carriage is stopped at each measurement position shown in the figure ,. After leveling the casing of the rotary drive unit 13 and the upper horizontal part of the frame 11-1 with the level 62,
The measurement position can be easily moved by performing the measurement in the transverse direction of the road RD from.

In the example shown in FIG. 1, the frame 1
It is also possible to set 1 as the frame 11-1 shown in FIG. 11 or FIG. 13 and install it on the road shoulder or outside the road. Further, in each of the above embodiments, an example in which the lightwave distance meter 19 is used as the distance measuring unit 14 has been described, but the present invention is not limited to this, and the same configuration as that of the conventional measuring unit 4 can be used, and the laser light Alternatively, infrared rays, ultrasonic waves, or the like can be used.

[0030]

As described above, according to the present invention,
Since the distance measuring unit is rotated by the rotation movement from the rotation driving unit, the size of the entire road surface shape measuring device can be sufficiently small and the weight thereof can be configured as compared with the measurement width of the road surface shape. Once this device is installed in the vehicle, it is not necessary to load and unload the device, and the operator can operate the device without going out of the vehicle for the measurement, thus saving labor. At the same time, since the operator does not have to go out of the vehicle, there is an effect that work on a dangerous road is eliminated and safety is increased.

By installing this device on the shoulder or outside the roadway, it is not necessary to regulate the roadway, so the labor, cost and time required for roadway regulation can be saved.
Moreover, there is an effect that traffic on the road is not caused due to the regulation, work on a dangerous road is eliminated, and safety is improved. Further, since the measuring mechanism is simple, there is an effect that it can be manufactured at a low price.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of an embodiment of a road surface shape measuring apparatus of the present invention.

FIG. 2 is a block diagram of an embodiment of a road surface shape measuring device of the present invention.

FIG. 3 is a block diagram of a lightwave rangefinder and a processing device that are examples of a distance measuring unit.

FIG. 4 is an explanatory view of the operation of the embodiment of the present invention.

5 shows an example of a measurement result of the road surface shape measuring device shown in FIG.

FIG. 6 is another embodiment of the rotation drive unit of the road surface profile measuring apparatus of the present invention.

FIG. 7 is another embodiment of the rotation drive unit of the road surface profile measuring apparatus of the present invention.

FIG. 8 is a scanning explanatory view of the embodiment shown in FIG.

FIG. 9 is a perspective view of a conventional road surface shape measuring device.

FIG. 10 is an explanatory diagram showing a measurement principle of a measuring unit of a conventional road surface shape measuring apparatus.

FIG. 11 is a perspective view showing the configuration of another embodiment of the road surface profile measuring apparatus of the present invention.

12 shows an example of the measurement result of the road surface shape measuring device shown in FIG.

FIG. 13 is a perspective view showing the configuration of another embodiment of the road surface profile measuring apparatus of the present invention.

[Explanation of symbols]

11, 11-1 Frame 12 Inclinometer 13, 40, 50 Rotation drive unit 14 Distance measurement unit 16 Processing device 19 Lightwave distance meter 30 Rotation center point 41, 51 Pulse motor 43 Micro step driver (pulse motor drive circuit) 52 , 53, 54, 55, 56, 57 Transmission mechanism 62 Level

Claims (7)

[Claims] 1. A road surface shape measuring device for measuring the shape of a road surface, comprising: a rotary drive unit that generates a rotary motion in a substantially vertical plane and outputs a signal related to the rotary angle; and a rotary drive unit. Inclinometer that detects the angle of inclination of the vehicle, a distance measurement unit that measures the distance to the road surface while rotating by the rotation movement from the rotation drive unit, the distance measurement value obtained by the distance measurement unit, and the inclinometer detects A road surface shape measuring device, comprising: a processing device that obtains a vertical distance and a horizontal distance from the road surface shape measuring device to the road surface by using the tilted angle and the turning angle output from the turning drive unit. 2. A road surface shape measuring device for measuring the shape of a road surface, comprising: a level; and a rotary drive section for generating a rotary motion in a substantially vertical plane and outputting a signal related to the rotary angle. Using the distance measurement unit that measures the distance to the road surface while rotating by the rotation motion from the rotation drive unit, the distance measurement value obtained by the distance measurement unit, and the rotation angle output from the rotation drive unit. A road surface shape measuring device comprising: a processing device for obtaining a vertical distance and a horizontal distance from the road surface shape measuring device to the road surface. 3. The road surface shape measuring device according to claim 1, wherein the distance measuring unit is a light wave range finder that measures a distance by irradiating a light wave toward a road surface and receiving a reflected wave thereof. 4. The rotation drive section has a pulse motor for generating a rotation motion and a pulse motor drive circuit for driving the pulse motor, and the pulse motor drive circuit outputs a signal relating to a rotation angle. Or the road surface shape measuring device according to 2. 5. The rotary drive unit converts a rotary motion that generates rotary motion and a rotary motion from the pulse motor into a reciprocating linear motion, and further converts the reciprocating linear motion to a predetermined point of the road surface shape measuring device. 2. A transmission mechanism for converting into a rotational movement in a substantially vertical plane, which is the center of rotation, and a pulse motor drive circuit for driving a pulse motor, wherein the pulse motor drive circuit outputs a signal relating to a rotation angle. Or the road surface shape measuring device according to 2. 6. The road surface shape measuring apparatus according to claim 1, wherein the road surface shape measuring apparatus is mounted on a vehicle. 7. The road surface shape measuring apparatus according to claim 2, wherein the road surface shape measuring apparatus is installed on a road shoulder or outside a road.