JPH0215802B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an electronic distance meter (EDM); a unit for determining the angle of rotation of the instrument in the horizontal plane as well as a unit for determining at least one angle of inclination; calculations for trigonometric transformations; The present invention relates to an electronic distance measuring instrument comprising a unit.

There is often a desire for a device that can easily and quickly measure distances and directions from one fixed point to a large number of distant measurement points. For example, measuring the length and direction of roads and tracks in suburban areas such as forests and fields. A measuring instrument meeting such needs would be easy to handle and would not require adjusting the measuring instrument to a special position before starting a measurement. It would also be advantageous for such a measuring instrument to be able to select a reference direction appropriately and to be able to measure a large number of measurement points with respect to this reference direction.

The present invention aims to provide such a measuring instrument. The feature of the measuring instrument of the present invention which achieves this object is that the device for determining the rotation angle of the instrument in the horizontal plane consists of a geomagnetic field detector, the geomagnetic field detector includes two detector units, and The detector units are oriented in different directions and fixed to the measuring instrument, such that the components of the earth's magnetic field in at least two directions in the coordinate system assigned to the measuring instrument are determined by the signals from said detector units. Furthermore, the calculation unit for the trigonometric transformation calculates the above-mentioned two values of the earth's magnetic field in the coordinate system assigned to the measuring instrument with the help of the results obtained from the device for determining the inclination angle. The component is converted to a coordinate system attached to the earth to calculate the direction of the earth's magnetic field on the earth's horizontal plane.

Of course, the distance measuring instrument is an electronic distance meter (EDM)
It is equipped with This electronic distance meter can measure distance more accurately by placing a reflector at the measurement point, or it can have a certain degree of accuracy (accurately acceptable depending on the field of use of the measured value) even without placing a reflector. ) to measure distance. The distance measuring instrument is also, of course, equipped with a device for determining the angle of inclination of the instrument when it is directed toward the measuring point. The measuring instrument is horizontally aligned by the operator. But this can be done simply "by feel." If accurate horizontal alignment of the measuring instrument is required, the measuring instrument is equipped with a spirit level.

A calculation unit consisting of a microprocessor calculates the horizontal distance from a fixed point to a measurement point and the rotation angle in the horizontal plane from a reference point. Determine the direction of the reference point with respect to the direction in the horizontal plane and store it in the memory of the microprocessor. The results of the calculations made by the microprocessor, that is, the measurement results, and the output signal from the tilt angle indicator for determining the tilt angle are preferably displayed as numerical values in the display unit of the measuring instrument, such as rotation angle, tilt angle, etc. Ru.

A more detailed description will be given below with reference to the accompanying drawings. FIG. 1 depicts a measuring instrument 1 according to the invention being used to measure the distance a of a path in a forest. This meter 1 is only supported by the operator 2 and does not have any supporting legs. The operator 2 first directs the instrument 1 to a properly selected and determined reference point 3. Note that the point standing from the operator 2 is the fixed point. A reflector is provided at the reference point 3. Next, the operator points the meter 1 at the measuring point 4 to be actually measured. This measurement point 4 is also provided with a reflector. Note that these reflectors are made of, for example, prisms. The meter 1 calculates and displays the horizontal distance a, the inclination angle θ, and the rotation angle (hereinafter simply referred to as rotation angle) φ in the horizontal plane with respect to the reference point 3 on the digital displays 5, 6, and 7, respectively.

Note that when performing reference measurements to determine the reference direction on the horizontal plane, the instrument 1 measures the horizontal distance to the reference point 3, its inclination angle, and the N- of the earth's magnetic field.
The rotation angle α in the horizontal plane from the S direction is displayed. Therefore, when performing a reference measurement, the operator 2 presses the operating unit 8, which is a push button, and when performing a subsequent normal measurement, he presses another operating unit 9, which is also a push button, to distinguish between the two. In addition,
The horizontal plane of the earth is indicated by three points, points P and Q, and meter 1.

The instrument 1 is further provided with a keyboard 10. The operator 2 instructs the keyboard 10 to perform measurements from a fixed point to a large number of measurement points in succession. Then, the memory of the microprocessor in the meter 1 sequentially stores the value of the rotation angle φ of each measurement point with respect to the reference point 3. Of course, the distance a and the inclination angle θ are also sequentially stored. When successive measurements are completed, the operator 2 can again operate the keyboard 10 to display desired measured values on the digital displays 5, 6, and 7. Furthermore, the measurement data recorded in the memory can be transferred to an external recording device such as a tape recorder.

FIG. 2 shows another embodiment of the measuring instrument 1 according to the present invention.
2 is shown. This measuring instrument 12 has one support leg 13 . Furthermore, this measuring instrument 12 is provided with a level 14. When taking a measurement, the operator 11 grasps the handles 39 on each side of the instrument 12 to horizontally align the instrument 12 and erect the support legs 13. In addition to the level 14, another level (not shown) may be provided in order to more positively position the meter 12 on a horizontal surface. Further, this is not limited to a spirit level, but may be an accelerometer or a pendulum-type tilt angle indicator. In the embodiment of FIG. 2, a special unit 38 with a keyboard and a digital display is attached to the support leg 13. Furthermore, a battery 15 is arranged below this special unit 38 for supplying current to the meter 12. When measurements are taken near frequently traveled roads or city tracks, the earth's magnetic field appears to fluctuate due to vehicles. Nevertheless, in order to make measurements possible, a geomagnetic field detector 55 is added as shown by the dashed line. This geomagnetic field detector 55 remains stationary during the series of measurements. The direction of the oscillating magnetic field measured by such a stationary geomagnetic field detector 55 is used as a reference direction for the geomagnetic field detector located in the measuring instrument 12, which is redirected for measurements.

FIG. 3 is a block diagram of a first embodiment of the interior of the measuring instrument of the invention. It first has a conventional electronic distance meter (EDM) 16. This electronic distance meter may be of a phase comparison type or a time measurement type. In this embodiment there are two tilt angle indicators 17,18. These may be of the accelerometer or pendulum type. An example of a suitable tilt angle indicator is shown in US Patent Application No. 37105.

Instruments 1, 12, 12' have rectangular coordinates X ₁ , Y ₁ , Z ₁
is attached. Axis X ₁ is measuring instrument 1, 12, 1
2' is aligned in the direction pointing to the measurement point. Axis Y ₁ is perpendicular to axis X ₁ and is oriented in alignment with the level when level indicator 14 indicates horizontal. Axis Z ₁ is axis X ₁ and axis
It is in the direction perpendicular to Y ₁ .

The tilt angle indicator 17 indicates whether the axis X ₁ of the measuring instrument 1, 12, 12' is aligned or tilted with respect to the horizontal plane of the earth, and the tilt angle indicator 18 indicates whether the axis X 1 of the measuring instrument 1, 12, 12' is aligned or inclined with respect to the horizontal plane of the earth. 1, 12, 12' axis Y ₁
indicates whether it is aligned or tilted.

Also, in the first embodiment shown in FIG. 3, two geomagnetic field detector units 20, 21 are provided. These are fixedly provided to the instruments so as to align with the axes X ₁ and Y ₁ of the coordinate system attached to the instruments 1, 12, 12'. Each such detector unit is the same as the detector for measuring the earth's magnetic field described in Swedish Patent No. 330,620. Briefly, each detector unit 20; 21 has two rod-shaped magnetic cores A', B';A'',B'' and a coil C', D'; C wound around each magnetic core. ″，D″ and
It consists of an output coil G′; G″ wound around a pair of coils C′, D′; C″, D″. Coil C′,
An appropriate alternating current voltage (for example, 400 Hz) is applied to D';C'',D'' via conductors E', F';E'',F''. Note that the direction of the magnetic flux generated by the coils C';C'' and the direction of the magnetic flux generated by the coils D';D'' are opposite to each other. Thereby, the earth's magnetic field in the detection direction of the detector unit is superimposed in opposite directions on the mutually oppositely directed magnetic fluxes. Thus, the direction of the detector unit, i.e. the magnetic core A′,
Information about the magnitude of the components of the earth's magnetic field in directions parallel to A'' and B', B'' is generated in the output coil G'; When biased from , the output signal is 800Hz
and has an amplitude of magnitude related to said component of the Earth's magnetic field. A control unit 24 is provided to input this to the microprocessor 33 as a digital value. Note that such a control unit 24 is well known and has various forms;
An example will be briefly explained below.

In the control unit 24, the output from the detector unit 21 is fed to an amplifier 26. The DC voltage portion of the output signal from the amplifier 26 is removed by a filter 27 and the remaining AC voltage signal is rectified by a rectifier 28. This rectified signal is converted to digital form in an analog/digital converter 29 and its output signal is passed to an indicating unit 30. Furthermore, this instruction unit 3
0 may be part of the microprocessor described below, but is shown here as a separate unit. The output signal from the indicating unit 30 is supplied to a digital/analog converter 32 after passing through a delay unit 31. This converter 32
causes the rectifier output signal to be fed back to the output coil G''. The magnitude and direction of this rectified voltage passing through the output coil G'' are changed by this rectified voltage to the magnetic core A''.
When the magnetic flux generated in the detector 21 at B'' directly compensates for the magnetic flux component of the earth's magnetic field,
The alternating voltage portion of the output signal is reduced to zero. However, a certain problem arises. I mean,
This is because the AC output signal from the output coil G'' has the same amplitude regardless of whether the earth's magnetic field is passing in one direction or in the opposite direction. Therefore,
The indicating unit 30 is configured to control the digital-to-analog converter 32 so as to produce a converted continuous voltage with a first polarity immediately after the signal obtained from the converter 29 is applied to the unit 30. It is configured. This is achieved, for example, by applying a "0" signal to one of the output lines. When the magnetic field produced by the output coil G'' associated with magnetic cores A'' and B'' coincides with the orientation of the earth's magnetic field,
A strong AC voltage output signal is obtained from this output coil G''.
When the signal supplied to the input of exceeds a predetermined value,
The indicating unit 30 changes the polarity of its output signal. This is done, for example, by producing a "1" signal on its polarity control output line, and the digital-to-analog converter 32 converts the polarity of the output signal. When the detector is placed in a purely east-west direction, the output voltage from the converter 32 increases again after the aforementioned polarity change, and thus the output signal of alternating voltage from the output coil G'' increases again. The switch value of the indicating unit 30 is reached.If this occurs for an additional period of time, the indicating unit 30 stops outputting the signal to the delay unit 31 and the converter 33 and at this time the signal from the unit 21 without feedback is removed. If the value of this signal is below a predetermined noise level, the output signal of the indicating unit 30 is set to zero, otherwise the operation of the control unit described above is repeated again. This is done with the polarity reversed.After the indicating unit 30 has conditioned the signal produced by the digital-to-analog converter 32, the output signal is applied to the input of a signal processing unit 33 (preferably a microprocessor). supplied to

After a predetermined period of time following the start of the measuring operation, the control units 23, 24 (obtained from the input signals from the indicating unit corresponding to the unit 30) will These signals are fed to the microprocessor 33 for stabilization. The microprocessor inputs include an electronic distance meter 16 and a slope angle indicator 1.
Outputs 7 and 18 are also connected. Furthermore, a manual setting unit 34 is connected to the microprocessor 33. This unit 34 informs the microprocessor whether the measurement being carried out is a reference measurement or a normal measurement. Selectable reference measurements can also be loaded into the microprocessor via said unit 34. Furthermore, the gradient of the earth's magnetic field at the measurement site is also read into the microprocessor. The slope can be read out from the table. This slope does not change to any appreciable extent on adjacent land.

The microprocessor 33 first obtains the magnitude of the earth's magnetic field in the direction of the axis Z ₁ of the coordinate system assigned to the measuring instrument from the tilt angle indicator 17 and, if present, another tilt angle indicator 18. the value of the angle, the values obtained from the detector units 20, 21 arranged in the directions of the axis X ₁ and axis Y ₁ of the coordinate system attached to the instrument, and the geomagnetic field read into the microprocessor. Calculate from the angle of slope. Thereafter, the coordinate system X ₁ , Y ₁ , Z ₁ attached to the instrument is converted to the coordinate system X, Y, Z attached to the earth. In addition, X ₁ , Y ₁ ,
Those with a 1, such as Z ₁ , are coordinate axes attached to the instrument, and those with nothing attached, such as X, Y, and Z, are coordinate axes attached to the earth. The coordinate axes X, Y, and Z attached to the earth have their origin at a fixed point at the measurement site.For example, axis X is along the meridian, axis Y is along the latitude, and axis Z is perpendicular to the horizontal plane at that point. It's along. Two axes X and Y in the horizontal plane of the coordinate axes given to the earth are specifically calculated, the direction of the vector in this horizontal plane forming the starting point for calculating the horizontal reference angle. If it is desired to omit the trouble of reading the angle of inclination of the earth's magnetic field, it is advisable to provide a detector unit 22 of the same type as the detector units 20 and 21. This unit 22 is mounted on the instrument in the direction of axis _Z1 and is provided with a similar control unit 25.

Following a transformation operation of the coordinate systems in which the origins of the two systems coincide, and based on the result in the horizontal plane of the earth, the microprocessor 33 calculates the rotation between the measurement direction in this horizontal plane and the direction of the earth's magnetic field. Calculate angles. If the measurement operation is after the reference measurement, the microprocessor 33 calculates the rotation angle from the reference direction. The values calculated by the microprocessor 33 regarding the horizontal distance, rotation angle, and tilt angle to the measurement point are displayed as numerical values in the display units 35 and 3.
6,37. These display units correspond to display units 5, 6, and 7 in FIG.
Further, the manual setting unit 34 corresponds to the special unit 38 in FIG.

FIG. 4 is a block diagram of a further embodiment of a measuring instrument according to the invention. This device does not have inclination angle indicators 17 and 18 as shown in FIG. 3, but only has a geomagnetic field detector. On the other hand, this measuring instrument is equipped with a level 14 as shown in FIG. This spirit level is designed so that the bubble within it will come to a predetermined position in the center only when the axis X ₁ and axis Y ₁ of the measuring instrument are perfectly aligned with the horizontal plane of the earth.
The geomagnetic field detector provided in this measuring instrument consists of three detector units fixed in alignment with the three axes X ₁ , Y ₁ , and Z ₁ of the coordinate system attached to the measuring instrument. When a series of measurements is started, the operator first adjusts the measuring instrument using the spirit level 14 so that it is completely horizontal. When the instrument is fully horizontally aligned, the operator presses a special key. Then, the microprocessor 33 calculates the direction and angle of inclination of the earth's magnetic field. Thereafter, measurements are taken from this fixed point to various measurement points. Since the magnitude, direction, and angle of inclination of the earth's magnetic field have been determined in advance, in subsequent measurements, the microprocessor uses the signals obtained from the detector units 20', 21', and 22' to control the measuring instruments. The inclination angle and rotation angle can be determined by geometric calculation.

Although the control unit 39' shown in FIG. 4 is configured differently from the control unit 24 of FIG.
It can be used in place of 4. The output signal from the detector unit 21' is amplified by an amplifier 40,
The DC portion is removed by a filter 41. The output of the filter 41 is input to a phase comparator 42 and a rectifier 45. The detector 21' is supplied with an alternating voltage derived from the output signal of an oscillator 43, the frequency of which is halved by a divider 44.
Therefore, the frequency of the output signal from the detector 21' will be the same as the frequency of the oscillator 43.

Comparator 42 compares the phase of oscillator 43 with the phase of the output signal from filter 41 . The output of rectifier 45 is coupled to a controllable sign converter 46. Comparator 42 directs sign converter 46 to one position or the other depending on whether the incoming signals are of the same or opposite phase. Code converter 4
The output of 6 is fed back to the output of the detector unit 21' and adjusted by this control unit so that the output from the detector is zero. The output of code converter 46 is also input to analog/digital converter 47. The output of this converter 47 is input to the microprocessor 33'. The value of this signal is proportional to the magnitude of the earth's magnetic field in the sensing direction of the detector unit 21'.

Referring to FIG. 4, it can be seen that a stationary geomagnetic field detector 48 is coupled to the microprocessor 33'. This geomagnetic field detector 48 is similar to the detector units 20', 21', 22'. In FIG. 5, a meter 12' having support legs 49 is shown. In cities and towns, or in locations adjacent to highways or highways, the Earth's magnetic field is influenced by automobiles and other motorized vehicles. Furthermore, other magnetic disturbance sources may also exist. When measurements are taken at such locations, the earth's magnetic field fluctuates. In such a case, the support legs 49
A geomagnetic field detector 48 is fixedly disposed within a housing 38' which is fixedly attached to the housing 38'. Then, during the measurement operation, the support legs 49 are kept immobile, and the measuring instrument 1 is
2' is made rotatable. So housing 3
The detected numerical value from the geomagnetic field detector 48 in the measuring instrument 12' is sent to the geomagnetic field detector unit 20' in the measuring instrument 12'.
This is used as a reference value for the detected values from 21' and 22', and the influence of fluctuations in the earth's magnetic field can be removed.
When the measured distances, rotation angles and inclination angles from different measurement points are calculated based on the differences obtained between the geomagnetic field detectors of two different installations, the geomagnetic field detector 48 of the fixed installation The two detection directions are placed on a horizontal plane and form a reference. Level 1
A spirit level 50 of the same type as 4 is provided on the support leg 49 to ensure correct horizontal positioning of the geomagnetic field detector 48.

A similar geomagnetic field detector 51 is shown in FIG. Since the inclination angle indicator 17 is present here, the earth's magnetic field detector 51 only requires two detector units. In FIG. 5, the measuring instrument 12' has a spirit level 52, which allows the operator to
can be positioned horizontally, sideways, etc. with respect to the measurement direction.

A geomagnetic field detector 55, indicated by a broken line in FIG. 2, is placed stationary on the ground in an arbitrary position during a series of measurements. This geomagnetic field detector 55 is the fourth
It consists of three detector units, such as the geomagnetic field detector 48 shown in the figure. When the detector unit is composed of two detector units, a level such as the spirit level 14 is provided in the box containing the geomagnetic field detector 55, and the two detector units are arranged so that the directions are parallel to the horizontal plane. remain stationary.

The present invention is not limited to the embodiments described, but can be modified in various ways without departing from the scope of the claims. For example, geomagnetic field detectors of different types than those shown in the drawings may also be used. A Hall generator is a suitable type of detector.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the use of a meter according to the invention; FIG. 2 is a schematic diagram showing the use of another embodiment of the meter according to the invention; FIG.
FIG. 4 is a block diagram schematically showing various internal elements constituting the instrument according to the invention; FIG. 4 is a block diagram schematically showing various internal elements of another embodiment of the instrument according to the invention. , FIG. 5 is a schematic external view of yet another embodiment of the instrument according to the invention. In the figure, 1, 12, 12' are measuring instruments, 2,
11 is the operator, 16 is the electronic distance meter, 17,1
8; 20', 21', 22', 23', 24', 3
9', 47', 33' are devices for determining the angle of inclination; 21-24, 33; 20', 21', 22';
23', 24', 39', 33' are devices for determining the rotation angle, 20, 21; 20', 21', 22'
is a detector unit that detects the earth's magnetic field, 33; 3
3' indicates a calculation unit for trigonometric function conversion.

Claims (1)

[Claims] 1. An electronic distance meter 16 and a device for determining at least one inclination angle (17, 18 in FIG. 3;
20', 21', 22', 23', 24' in Fig. 4,
39', 47', 33') and a device for determining the rotation angle of the instrument in the horizontal plane (21 in Figure 3).
-24, 33; 20', 21', 22' in Figure 4,
23', 24', 39', 33') and a calculation unit 33; 33' for trigonometric conversion, all without the need to place the instrument horizontally before the measuring operation. In order to obtain the angle of rotation in the horizontal plane in the possible directions of The geomagnetic field detector consists of at least two detector units (2 in Figure 3) fixedly mounted on the electronic distance measuring instrument.
0, 21; 20', 21', 22' in Fig. 4), these two detector units are oriented in different directions and with the aid of the signals of these detectors are attached to the measuring instrument. Provision is made that at least two components of the earth's magnetic field in the coordinate system are determined, and said calculation unit 33, 33', with the aid of the results obtained from said device for determining the inclination angle, be configured to convert the components of the earth's magnetic field from a coordinate system attached to the measuring instrument to a coordinate system attached to the earth, and to calculate the direction of the earth's magnetic field in a horizontal plane; An electronic distance measuring instrument featuring: 2. In order to carry out a reference measurement in order to establish a certain reference direction in the horizontal plane, the rotation angle in the horizontal plane between the direction of the earth's magnetic field and an arbitrarily selected reference direction is determined via the operating unit 8 in the memory formation of the calculation unit 33. In order to perform a normal measurement following the reference measurement, the calculation unit 33 calculates a rotation angle in a horizontal plane with respect to the reference direction. The electronic distance measuring instrument according to item 1. 3. An arbitrarily selected reference direction can be read into the memory of the calculation unit via the manual setting means 34; said calculation unit 33 then The first aspect of the present invention is to calculate the rotation angle in the horizontal plane of the measurement made in the first aspect of the invention.
Electronic distance measuring instrument as described in Section 1. 4 There are two geomagnetic field detector units, and the gradient of the geomagnetic field at the measurement location is manually set by means 3.
4; the device for determining the inclination angle includes at least one inclination angle indicator arranged in a predetermined direction in the coordinate system assigned to the measuring instrument; 17, 18; said calculating unit 33 calculates the angle of rotation in the horizontal plane with the aid of the signals obtained from said detector unit, said tilt angle indicator and said read value of the tilt of the earth's magnetic field. Claim No. 1
The electronic distance measuring instrument according to any one of items 1 to 3. 5. There are three geomagnetic field detector units located in different directions from each other so that with the aid of the signals from these detector units the geomagnetic field is established in a three-axis coordinate system given to the measuring instrument. ; means 1 for horizontally aligning the measuring instruments;
4, whereby the measuring instrument is adjusted to a predetermined position with respect to the horizontal plane of the earth; the magnitude and direction of the earth's magnetic field are read into the memory of the calculating unit by means of the measuring instrument in this position; during subsequent measurements, the calculation unit 33 calculates the angle of rotation in the horizontal plane, the angle of inclination and, concomitantly, the horizontal distance to the measuring point from the stored value of the earth's magnetic field from said earth's magnetic field detector and from said earth's magnetic field detector; 4. Calculation with the aid of the values obtained by reference measurements, in which said calculation unit 33 is part of a tilt angle unit. electronic distance measuring instrument. 6. The instrument is equipped with a spirit level 52, by means of which the instrument is adjusted during the measuring operation so that a known line in the coordinate system attached to the instrument is aligned with the horizontal plane of the earth. 6. The electronic distance measuring instrument according to any one of items 5 to 6. 7. Further geomagnetic field detector 48; 51, 55 with at least two detector units in the instrument.
, which detector is arranged stationary in a coordinate system attached to the earth; said calculation unit 33 also calculates the angle of rotation in the horizontal plane, the angle of inclination and, incidentally, the horizontal distance from the two geomagnetic field detectors. 6. An electronic distance measuring instrument according to claim 1, adapted to calculate with the aid of the signals obtained.