JP2001074456A - Method and apparatus for measurement of position of instrument equipped with cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position measuring method for an instrument which is used underwater or in the ground. SOLUTION: When the position of an underwater instrument, which is fixed to the tip of a cable 2 and which is remote-controlled or power-supplied via the cable 2 is measured, the cable 2 is passed inside a tube 6 which is formed by connecting a plurality of segments in series, the angle between the front segment and the rear segment of the tube 6 is detected, the bent shape of the cable 2 is detected, and the position of the instrument at the tip of the cable 2 is measured. By this method, the position of the instrument, whose position cannot be measured by electromagnetic waves or sound waves and which is used underwater or in the ground, can be measured with good accuracy without being affected by the environment of water or soil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for measuring the position of a device to be remotely controlled or supplied with power via a cable.

[0002]

2. Description of the Related Art As devices to be remotely controlled or supplied with power via the above-described cable, there are a cabled underwater probe, an RO
There are devices such as V (Remotely Operated Vehicles), underground locating machines, and pipe inspection robots. As a method of measuring the position of these devices, an electromagnetic wave measurement system (G
PS, etc.), an optical measurement system (such as an autofocus of a camera), an LBL (Long BaseLine) system or an SBL (Short BaseLine) system using ultrasonic waves are often used.

[0003]

However, the above-mentioned electromagnetic wave measuring system and optical measuring system are not suitable for use in machines used underwater or underground, robots for inspecting the inside of pipes, and the like. It cannot be used because it does not arrive. In addition, LBL or SBL systems that can be used in water are not necessarily required due to their long sampling time intervals, low accuracy of measurement data because they are greatly affected by the environment such as water quality and flow, and high noise components. Performance could not be provided.

[0004] It is an object of the present invention to provide a position measuring method and apparatus capable of accurately measuring the position of equipment used underwater or underground.

[0005]

According to a first aspect of the present invention, there is provided a method for measuring a position of a device fixed to a distal end of a cable and remotely controlled or supplied with power via the cable. Measuring the position of the device at the tip of the cable by detecting the angle between the front and rear cylinders of the tube by passing the cable through a tube formed by connecting a plurality of cylinders in series. It is a feature.

[0006] According to this method, the bent shape of the cable is detected by detecting the angle between the respective cylinders, and thus the position of the device fixed to the end of the cable is measured. According to a second aspect of the present invention, there is provided an apparatus for measuring a position of a device which is fixed to a distal end of a cable and which is remotely operated or supplied with power via the cable, wherein a plurality of cylinders are connected in series. A tube formed and disposed between the tubes for passing the cable, a switch disposed between the cylinders of the tube, and operating according to an angle between the cylinders, and determining whether the switch is operating. Determining means;
Calculating means for calculating the position of the device based on the state of the switch means which has been operated or not operated, which has been determined by the determination means.

According to this configuration, it is determined whether the switch means that operates according to the angle between the cylinders is operating,
The bent shape of the cable is detected based on the determined state of each switch means, and the position of the device fixed to the end of the cable is measured. The invention according to claim 3 is the invention according to claim 2, wherein the first cylindrical body of the tube arranged at the cable fixed end opposite to the fixed end of the device is rotatably supported. And a rotation angle detecting means for detecting a rotation angle of the first cylindrical body supported by the supporting means.

According to this configuration, the planar position of the device is measured by the bent shape of the cable, and the inclination of this plane is detected by the rotation angle of the first cylinder, so that the three-dimensional position of the device is measured. Is done. The invention described in claim 4 is the invention described in claim 2 or claim 3,
Each tube body of the tube is rotatably connected in both directions from a linear arrangement, and the switch means is configured to detect a rotation direction of the tube body.

According to this configuration, it is determined whether the switch means that operates in accordance with the angle between the cylinders that rotate in both directions is operating, and the bent shape of the cable is determined based on the determined state of the switch means. While detecting, the position of the device fixed to the end of the cable is measured,
By connecting each tubular body of the tube so as to be rotatable in both directions from the linear arrangement, the cable passing through the tube can be freely bent in a plane, and the degree of freedom of movement of the device can be increased. .

[0010] The invention described in claim 5 is the second invention.
5. The invention according to claim 4, wherein the judging means is disposed through each of the cylinders, and is disposed through each of the first and second input lines to which a voltage is simultaneously applied. An output line to which one end of the switch means is connected, and a first cylinder connected to the first input line for each cylinder in series, and further provided with a second input line at a fixed end of the cable. A first time delay element connected in series for each cylinder other than the body, and having a longer time delay characteristic than the first time delay element, connected to the second input line in the first cylinder, A second time delay element connected in series with the first time delay element of the other cylinder, and connected to the first input line and the second input line each time each cylinder is connected, and a difference between the voltages of these input lines. And outputs the output voltage to the other end of the switch means. An arithmetic element to force, by measuring the voltage output to the output line, is characterized in that each switching unit has a determining configure whether running.

According to this configuration, the first input line and the second input line
When a voltage is simultaneously applied to the input lines, a pulse is formed as an output of the arithmetic element due to the time difference between the time delay of the second time delay element of the second input line and the time delay of the other first time delay element. . This pulse signal is supplied to the output line when the switch means is in the ON state, and by observing pulses generated sequentially for each delay time of the first time delay element, the ON / OFF state of each switch means is sequentially determined. Is determined.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In many cases, a target device used underwater is connected between a remote device and an operator by a control cable or a power supply cable, and remote control or remote monitoring is often performed via the cable. . If the shape of the cable can be measured, the relative position between the device and the operator can be measured.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a configuration diagram of a positioning system in which a position measuring device according to Embodiment 1 of the present invention is applied to underwater equipment. In FIG. 1, reference numeral 1 denotes an operation console which also serves as a measurement console and is operated by an operator, and is connected to an underwater device 3 which is a target device by a cable 2.
It is an object of the present invention to measure the position of the target underwater equipment 3 in the coordinate system XYZ of the operation console 1.

FIG. 2 shows a cable connection device attached to the operation console 1. Cable 2 is hollow tube 6
This tube 6 has n (n is a positive integer of 2 or more) segments (an example of a cylinder) (1) to
(N) are connected in series to cover the entire cable 2. A segment connected to the operation console 1, which is a fixed end of the cable 2, is referred to as a segment (1).
The segment connected to the adjacent segment (1) is referred to as segment (2), and segments (3), (4),.
(Up to the fourth item in FIG. 2).

As shown in FIGS. 3A and 3B, the segment (1) connected to the operation console 1 is a bearing (an example of a support means) provided on the operation console 1.
5 and is configured to be freely rotatable with respect to the axis of the bearing 5. The rotation angle a of the segment (1) is defined as shown in FIG. The origin of the console coordinate system XYZ is at the center axis of the bearing 5.

The detailed structure of the segment will be described with reference to FIGS. FIGS. 4A and 4B show segments (i), (i + 1), and (i + 2).
The segment (1) of 1 is a segment connected to the operation console 1. Each segment (i) has a length of k meters and the same shape, and is formed from a cylindrical body 7 having a substantially semicircular space (a space through which the cable 2 passes) in cross section. (I + 1) and (i + 2) are couplings 11 at the front and rear ends of the flat portion 8 of the cylindrical body 7, respectively.
Connected by Rotation angle a of segment (1)
When (FIG. 3) is at zero, the front shape of the segment is as shown in FIG. 4 (c).

As shown in FIGS. 5 (a) and 5 (b), a concave portion 12 is provided at the rear end of the curved surface portion 9 of the cylindrical body 7 of each segment (i). A convex portion 13 made of an elastic body that divides the concave portion 12 into front and rear portions is provided. At the front end of the curved surface portion 9 of the cylinder 7 of each segment (i + 1) except for the segment (1), the convex portion 13 separates the front and rear portions. An engaging body 15 having a projection 14 that engages with the recess 12 is provided, and the angle (state) of the coupling 11 is maintained in one of two states of 0 degree or b degree depending on the position where the projection 14 engages. You. If it is 0 degrees,
The two segments (i) (i + 1) are a straight line, and if it is b degrees, the segment (i + 1) bends by b degrees.
Generally, the angle b is a small angle. [Position measurement of remote device] As shown in FIG.
Is on the XY plane of the fixed console 1 and below the X axis (the Y position is minus), the rotation angle a (FIG. 3) of the segment (1) becomes zero.

As described above, the length of one segment (i) is k meters, the number of segments from the operation console 1 to the underwater equipment 3 is n, and a segment (i) and a segment (i + 1) When the angle of a certain coupling (i) is θ _i (θ _i is 0 degree or b degree, in the example of FIG.
Degrees), as shown in FIG. 6, the angle ψ _i between the segment (i) and the X axis can be obtained by the following equation 1.

[0019]

(Equation 1) Therefore, the position of the underwater equipment 3 connected to the last segment (n) is given by the following equation 2.

[0020]

(Equation 2) When the underwater equipment 3 is not on the XY plane of the operation console 1,
The rotation angle a (FIG. 3) of the segment (1) is not zero.
When the rotation angle is a, the position of the underwater equipment 3 is given by the following equation 3.
Given by

[0021]

(Equation 3) Therefore, if the rotation angle a of the segment (1) and the state θ _i of each coupling 11 are measured, the position of the underwater equipment 3 can be measured without being affected by the environment such as water or soil.

In order to measure the rotation angle a, sufficient accuracy can be obtained with a general encoder. As shown in FIG. 3B, a ring 16 on which an optical pattern in which straight lines are arranged at equal intervals is fitted into the end of the segment (1) opposite to the segment (2). A two-phase pulse output type encoder 18 is provided at a position where the ring 16 is irradiated with a parallel light beam from a light source 17 and receives the reflected light. The encoder 18 is capable of detecting normal rotation and reverse rotation of the segment (1). I have. A two-phase pulse signal generated by the encoder 18 according to the reflected light (optical pattern) of the ring 16 is transmitted to a measuring device 25 provided on the operation console 1.
(FIG. 7).

As shown in FIG. 7, the operation console 1 comprises:
It is composed of the measuring device 25 and an operating device 26 of the underwater device 3 connected to the underwater device 3 via the cable 2. The measuring device 25 is connected to the encoder 18, and adds and subtracts the number of pulses of the two-phase pulse signal input from the encoder 18 according to the normal rotation and the reverse rotation of the ring 16 to thereby set the rotation angle a of the segment (1). A rotation angle detection unit 27 for detecting, a switch operation determination unit 28 (details will be described later), a calculation unit 29 (details will be described later) for calculating the three-dimensional position of the underwater device 3 by the above-described equations 1 to 3, The storage unit 30 stores data on the three-dimensional position of the underwater device 3 obtained by the calculation unit 29.

To measure the angle of each of the couplings 11, an encoder may be attached to each of the couplings 11. However, as the overall length of the cable 2 increases, the number of segments and couplings 11 increases, and the cost of the encoder and the complexity of wiring increase sharply. [Measurement Electric Circuit] In the present invention, the measurement electric circuit shown in FIG. This measuring electric circuit and the switch operation determining means 28 of the measuring device 25
Thus, a determination unit is formed.

In FIG. 8, reference numeral 20 denotes the coupling 11
Is a coupling switch which is turned on when the angle of the coupling 11 becomes 0 degree, and turned off when the coupling 11 becomes the state of the degree b.
It is provided for each one. An example of the coupling switch 20 is shown in FIG. Tip of projection 14 and front recess 12
, A conductor 20A is provided, and when the coupling 11 becomes 0 degree, the conductor 20A comes into contact with the electric wiring 24 disposed in the segment.
Are formed so as to conduct.

An input line A (first input line) and an input line B are input from the switch operation determining means 28 of the measuring device 25 through each segment (1) (2).
(Second input line) and an output line C are provided.
A first time delay element (such as a capacitor) 22 having a time delay characteristic (delay time T _A ) is connected in series to each of the input lines A and B for each segment. However, only the input line B of the segment (1) has a time delay characteristic {delay time T _B (> T _A )} longer than the first time delay element 22 instead of the first time delay element 22. A time delay element (such as a capacitor) 21 is connected.

Further, for each coupling 11 of each segment, there is provided an operation element (subtractor) 23 which is connected to the input line A and the input line B and calculates the difference between the voltages of the input line A and the input line B. The output terminal of the arithmetic element 23 is connected to one end of the coupling switch 20 via the electric wiring 24, and the other end of the coupling switch 20 is connected to the output line C.

A method of measuring the state of the coupling 11 by the circuit of FIG. 8 will be described with reference to the characteristic diagram of FIG. FIG. 9 shows a voltage change when a constant voltage is simultaneously applied to the input line A and the input line B at a certain time t ₀ .
(A) to (c) are shown. The voltages for each segment (1) (2)... (N) of the input line A are denoted by Al, A2,... An, and the voltages for each segment of the input line B are B1 and B.
,... Bn, and the output voltage of each segment of the arithmetic element (subtractor) 23 is indicated by Cl, C2,.

A time delay element 2 is connected to the input side of the arithmetic element 23.
According to the characteristic (delay time T _A ) of segment 2, segment (1)
Segment (2), the order of the third segment (3) is an input voltage from the input line A is applied after a delay time T _B by the second time delay element 21, likewise the segment from the segment (1) (2) from, In the order of the third segment (3), the input voltage is applied from the input line B, and the input voltage applied from the input line A is canceled by the input voltage applied from the input line B in the arithmetic element 23. _A pulse signal having a pulse width (T _B -T _A ) is generated at the output voltage of 23, that is, at the input side of the coupling switch 20.

When the couplings 11 are all at 0 degrees, that is, when the cable 2 is not bent and the coupling switches 20 are all on, the voltage change measured at the output line C is shown in FIG. Show. The pulse signal applied to the input side of the coupling switch 20 has a time T.
It is measured continuously for each _A. FIG. 10 shows an example when the couplings 11 are not all at 0 degrees, that is, when the cable 2 is bent and a part of the coupling switch 20 is off.

In the example of FIG. 10A, the segment (1)
From state to segment (5), the state of the coupling 11 is b degrees, 0, 0, and b degrees, respectively.
As shown in (b), the coupling switch 20 of the coupling (1) between the segments (1) and (2) and the coupling of the coupling (4) between the segments (4) and (5). The switch 20 is off.

In this state, as shown in FIG.
Of the coupling switch 20 in the on state.
The above pulse signal appears on the output side, but it turns off.
The output of the coupling switch 20 is
Does not appear. Therefore, the switch 20, that is, the coupling
Observed at output line C due to the state of ring 11
Is applied to the input lines A and B at the same time.
Interval t₀More time t₁~ T _TwoState of voltage between, time t_Three~ T_Four
State of voltage between, time t_Five~ T₆State of voltage between, time t
₇~ T₈Observe the state of the voltage between the cups in order
The state of the ring 11 can be determined.

Therefore, the switch operation judging means 28 applies a voltage to the input line A and the input line B at the same time and observes the output voltage of the output line C, thereby coupling each segment (1) to (n). 11 (0 degree or b degree) can be determined, and the state of the coupling 11 determined in order (number i of coupling 11 and angle θ _i (0 degree or b degree) in Equation 1) is calculated. Output to means 29.

The calculating means 29 calculates the rotation angle a of the segment (1) detected by the rotation angle detecting means 27 and the state of each coupling 11 determined by the switch operation determining means 28 based on the above equations (1) to (3). By underwater equipment 3
Is calculated and output to the storage means 30. As described above, even in water where position measurement by electromagnetic waves or sound waves cannot be used, by measuring the bent shape of the cable 2, the position of the target underwater device 3 can be changed without being affected by the environment such as water quality or flow. Measurement can be performed with high accuracy. Further, since the measuring means is provided in the fixed operation console 1 and the tube 6 of the cable 2, a new position can be measured immediately even when the underwater equipment 3 moves. Although the shape of the cable 2 cannot be freely changed (a spiral cable shape or the like is impossible), it can be expected that in an environment such as underwater, the movement of the target device is hardly affected. In addition, the measurement is repeated every time, and the data of the three-dimensional position of the underwater device 3 is stored in the storage unit 30, whereby the trajectory of the underwater device 3 can be obtained.

In the first embodiment, the states of all the couplings 11 are output from the switch operation determining means 28 to the calculating means 29, but only the number i of the coupling switch 20 in the off state is calculated. The information may be output to the means 29. At this time, the calculating means 29 determines that the angle θ _i of the input number i coupling 11 is b degrees and inputs the number i coupling 11 that has not been input.
Of the angle theta _i is determined as 0 °, the above equation 1 equation 3 to calculate a three-dimensional position of the underwater equipment 3. (Embodiment 2) FIG. 11 shows a configuration of a tube of a position measuring device according to Embodiment 2 of the present invention.

As shown in FIGS. 11A and 11B, each segment (i) of the tube 6 is formed in a cylindrical shape, and the upper and lower portions of the rear end are cut into a triangular shape at an angle θ from the horizontal plane. In addition, the upper and lower portions of the front end of the other segment (i + 1) except for the segment (1) are each cut into a triangular shape at an angle θ from the horizontal plane, and the lower portion of one apex is shown in FIG.
The driving body 32 of the first coupling switch 31 shown in FIG. 2A is used, and the upper part of the other top is the second driving body 32 shown in FIG.
The drive unit 34 of the coupling switch 33 is configured. Also, the rear end and the front end of the triangular apex are engaged and coupled to each other, so that the segment (i)
When (i + 1) is located on a straight line, the angle formed by the rear end and the front end is 2θ.

As shown in FIG. 12A, in the first coupling switch 31, the segment (i + 1) is formed on one side surface of the rear end of each segment (i), and the segment (i + 1) has an angle (+
θ) (+ is downward), and is provided at a position operated by the driving body 32 when it bends, and as shown in FIG.
The coupling switch 33 is provided on the other side surface at the rear end of each segment (i), and at a position where the driving body 34 operates when the segment (i + 1) is bent by an angle (-θ).

Due to the structure of the tube 6, the segments (i) and (i + 1) can be rotated in both directions (up and down) from the linear arrangement, and the rotation directions are respectively changed by the first and second coupling switches 31. , 33. Therefore, the measurement electric circuit shown in FIG.
By providing two circuits for each segment, it is possible to determine that each segment is bent upward {angle (−θ)} or downward {angle (+ θ)}. Thereby, the position of the underwater device 3 can be measured. When both the first and second coupling switches 31 and 33 are off, the segment (i) (i + 1) is regarded as a straight line (angle 0).

As described above, the position of the underwater equipment 3 can be measured, and the segment (i) of the tube 6 can be measured.
Since (i + 1) is configured to be rotatable in both directions (upward and downward) from the linear arrangement, the cable 2 can be freely bent in a planar manner (up and down).
Can be increased, and the movement of the underwater equipment 3 can be made smoother. (Embodiment 3) FIG. 13 shows a configuration of a tube 6 of a position measuring device according to Embodiment 3 of the present invention.

As shown in FIGS. 13 (a) and 13 (b), a concave portion 41 is provided at a part of the rear end of the curved surface portion 9 of the cylindrical body 7 of each segment (i) of the tube 6, and a push is formed in the concave portion 41. A coupling switch 42 composed of a button switch is built in, and the surface of the concave portion 41 is covered with a sealing material 43 composed of an elastic body. The concave portion 41 is provided at the front end of the curved surface portion 9 of the cylindrical body 7 of the other segment (i + 1) except for the segment (1).
, A convex portion 44 is provided to face the segment (i) (i +
When 1) is located on a straight line, the coupling switch 4
2 is pressed by the convex portion 44 to operate.

With the construction of the tube 6, the fact that the segment (i + 1) is bent indicates that the coupling switch 42
Is turned off, and therefore, if the circuit shown in FIG. 8 is used, it can be determined that each segment is bent, and the position of the underwater device 3 can be measured by the above equations 1 to 3. Can be. Thus, the position of the underwater device 3 can be measured.

As shown in FIG. 14, a projection 45 is provided at a part of the rear end of the curved surface portion 9 of the cylindrical body 7 of each segment (i) of the tube 6, and the recess 41 is provided therein. A coupling switch 42 made of a push button switch may be built in the inside 41, and the surface of the concave portion 41 may be covered with a sealing material 43 made of an elastic body. At this time, the cylinder 7 of the segment (i + 1) faces the recess 41.
The convex portion 44 is provided on the curved surface portion 9.

In the first to third embodiments, the target device is the underwater device 3. However, the target device is not limited to the device that moves underwater, and is used for position measurement of the device that moves in the ground or inside a pipe. can do.

[0044]

As described above, according to the present invention, even when the position measurement by electromagnetic waves or sound waves is not possible, such as equipment used underwater or underground, the position of the target equipment can be changed to the environment such as water or soil. The measurement can be performed accurately without being affected by the measurement.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a positioning system to which a position measuring device according to a first embodiment of the present invention is applied.

FIG. 2 is a perspective view of a main part of an operation console and a cable connection device of the position measuring device.

FIG. 3 is a view showing the arrangement of a bearing of a cable connecting device of the position measuring device and a configuration of a detecting device for detecting rotation of a tube segment.

FIG. 4 is a detailed explanatory view of a tube and a segment of the position measuring device.

FIG. 5 is a diagram showing a coupling state and a configuration of a coupling switch of the position measuring device.

FIG. 6 is an explanatory diagram of position measurement of a target device of the position measurement device.

FIG. 7 is a configuration diagram of the position measurement device.

FIG. 8 is a measurement electric circuit diagram of the position measurement device.

FIG. 9 is a characteristic diagram of a measurement electric circuit of the position measurement device.

FIG. 10 is a characteristic diagram illustrating an example of a measurement result of a measurement electric circuit of the position measurement device.

FIG. 11 is a side view and a plan view of main parts of a tube segment of the position measuring device according to the second embodiment of the present invention.

FIG. 12 is a layout view of a coupling switch of the position measuring device.

FIG. 13 is a diagram illustrating a mounting of a coupling switch of a tube segment of the position measuring device according to the third embodiment of the present invention.

FIG. 14 is another mounting view of the coupling switch of the tube segment of the position measuring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Operation console 2 Cable 3 Underwater equipment 5 Bearing 6 Tube 11 Coupling 12 Depression 13 Convex part 14 Projection 15 Engagement body 16 Ring 17 Light source 18 Encoder 20 Coupling switch 21 Second time delay element 22 First time delay element 23 Arithmetic element 24 Electrical Wiring 25 Measuring Device 26 Operating Device 27 Rotation Angle Detecting Means 28 Switch Operation Discriminating Means 29 Computing Means 30 Storage Means 31, 33 Coupling Switch 32, 34 Driver 41 Depression 42 Coupling Switch 43 Sealing Material 44 Projection

Claims (5)

[Claims] 1. A method for measuring a position of a device fixed to a tip of a cable and remotely controlled or supplied with power via the cable, wherein the cable is formed by connecting a plurality of cylinders in series. And measuring the position of the device at the end of the cable by detecting the angle between the front and rear cylinders of the tube through the inside of the set tube. 2. A device for measuring the position of a device which is fixed to a tip of a cable and which is remotely operated or supplied with power via the cable, wherein the device is formed by connecting a plurality of cylinders in series, A tube that passes through, a switch that is disposed between the respective cylinders of the tube, and that operates according to an angle between the respective cylinders; a determination unit that determines whether the respective switch is operating; A position measuring device comprising: a calculating means for calculating a position of the device based on a state of an operating or non-operating switch means determined by the determining means. 3. A support means for rotatably supporting a first cylindrical body of a tube disposed at a cable fixed end on the other side of the fixed end of the device, and a first cylindrical body supported by the support means. 3. The position measuring device according to claim 2, further comprising a rotation angle detecting means for detecting a rotation angle of the position. 4. The tube according to claim 1, wherein each of said tubes is rotatably connected in both directions from a linear arrangement, and said switch means is capable of detecting the direction of rotation of said tube. The position measurement device according to claim 2 or 3. 5. The first determining means, which is provided through each of the cylinders and is simultaneously applied with a voltage.
An input line and a second input line, an output line provided through each cylinder, and one end of the switch means connected thereto, and an output line connected in series to the first input line for each cylinder, An input line, a first time delay element connected in series for each cylinder except for the first cylinder disposed at the cable fixed end, and a time delay characteristic longer than the first time delay element. A second time delay element connected to the second input line at a first cylinder and connected in series with a first time delay element of another cylinder, and a first input line for each connection of each cylinder. And a computing element connected to the second input line for calculating the difference between the voltages of these input lines and outputting the output voltage to the other end of the switch means, and measuring the voltage output to the output line. By this, each switch means operates Position measuring device according to any one of claims 2 to 4, whether characterized in that a determining configure whether there.