Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B11/00—Measuring arrangements characterised by the use of optical techniques
  • G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
  • G01C15/00—Surveying instruments or accessories not provided for in groups G01C1/00 - G01C13/00
  • G01C15/002—Active optical surveying means

Definitions

• the invention relates to a method for transmitting angles between two devices at different locations, and a device for performing this method.
• the method and the device are used, for example, for the contactless transmission of an azimuth angle, as is e.g. in the field of geodesy, navigation, for coordinate transfer to machine tools and in similar applications.
• Previously known methods and devices for contactless angle transmission are based on the principle of auto-reflection or auto-collimation, or on the principle of collimation.
• auto reflection an observation telescope and a prism arranged at the second location are roughly aligned with one another by rotating or sliding until the telescope is located within a parallel strip which runs at right angles to the edge of the prism roof.
• the width of the parallel strip mentioned corresponds to the length of the roof edge of the prism.
• the prism roof edge To transmit an azimuth related to the geographic north direction, the prism roof edge must be horizontal and it must have a fixed reference to the device reference of a device connected to the prism.
• a beam directed from the telescope to the prism is reflected in it so that it emerges again in the plane that is spanned by this beam itself and the prism edge, that is to say that the beam is deflected azimuthally and always returns vertically at the same angle as it enters the prism.
• the telescope is rotated azimuthally until the image of the telescope or an observation theodolite, which is visible in the prism, is exactly symmetrical to the vertical line of one in the telescope or in the theodolite arranged cross hairs. If this is the case, the target axis is exactly perpendicular to the roof edge of the prism.
• this method which is relatively simple for an operator, has the disadvantage that the measurement or transmission distance depends on the minimum target range of the telescope set to twice the target distance. For normal telescopes, this minimum target range does not extend to a distance of less than approx. 1 m.
• a telescope In the principle of autocolliation, a telescope is focused on infinitely, with a crosshair being imaged on the collimator and a plane mirror in front of it, which is adjusted perpendicular to the optical axis. To transmit an azimuth angle, it is sufficient if the image of the crosshair is only coincident with the crosshair itself in one axis, for example only in the vertical line. Autocollimation is suitable for relative short target ranges. For the user, however, the condition is more difficult to set than the auto reflection. The principle of autocollination therefore places higher demands on the operator.
• Fig. 3 shows a second embodiment with a
• FIG. 4 shows an arrangement according to the principles of FIG. 3, for the simultaneous transmission of two angles
• 6A-C the code patterns drawn in the beam path of the measuring device and their images for different measurement configurations
• 7 shows an evaluation device for processing the signals supplied by the detector cells according to FIG. 5.
• the principle of the angular transmission from a first device to a second one is based on the measurement of a deposit which occurs when a geometric code pattern is transmitted between a first and a second device.
• the storage registered in one of the two devices is e.g. detected by a group of detector cells and subjected to analytical signal processing.
• the direction information transmitted from the first to the second device e.g. an angle information related to a common reference.
• a single angle for example an azimuth angle
• a second angle e.g. in addition to the azimuth mentioned also an associated elevation angle.
• a telescope 1 is aligned with the north direction N under an azimuth 'phi 1'.
• the same angle is to be transferred to a second device 2, which, however, is still under the azimuth 'phi 2' with respect to the north direction N.
• the second device can be connected to a directional device, for example a sharply focused directional antenna, such as is used for satellite radio.
• any other elements for example adjustable parts of a machine tool, could also be used with the second device can be coupled or connected.
• the misdirection of the second device is noticeable in an angular deviation 'delta' between the two optical axes of the devices.
• the angle 'delta 1 As a measurement criterion for the angle transmission.
• two telescopes 1 and 2 are initially roughly aligned with one another, as shown in FIG. 2.
• the telescope 1 is provided with an opening angle '2 alpha', while a second telescope belonging to the second device has a second opening angle '2 beta'.
• a linear code pattern 3 for example a bar code
• a lamp 4 from the first telescope 1 and transmitted into the image plane of the second telescope 2.
• the image of the code pattern is shown laterally shifted by a certain amount in the second telescope. This shift is detected by a group of detector cells 3A, 33, 3C ... and processed in a signal processing device.
• the signal processing results in the degree of deviation of the code pattern image in the image plane of the second telescope from a predetermined reference value at which the devices are aligned with one another.
• the detector signal obtained thus indicates agreement or the extent of the deviation from a direction to be transmitted or from an angle to be transmitted.
• 3 shows a further exemplary embodiment of a device for angular transmission with a transmitting optic 10, a rotatable roof prism 11 and one or more receiving collimators 12A, 12B, 12C, each of the collimators having a group of detector cells 13, 14, 15 is seen.
• a linear code 16 for example a bar code, is transmitted from the transmitting optics 10 to the roof prism 11 with the aid of a light source 17 and is reflected by the latter into the receiving collimator device 12.
• the image of the code pattern transmitted by the transmitting optics 10 appears in the receiving collimator 12 as a different image, namely with a lateral shift which corresponds to the change in the rotational position of the roof prism with respect to a reference position.
• the signals detected by the collimator device 12 and the detector groups 13, 14, 15 are fed to a signal processing device, which will be discussed later.
• This signal processing device automatically detects the storage of the received bar code image from a reference position and detects it as an angular storage of the prism 11, or outputs it as a correction signal for tracking a device connected to the prism 11.
• a device whose angular position is to be transmitted or detected is provided with a mirror 20.
• the mirror 20 is illuminated by an optical transmitter 21 which transmits the code of a two-dimensional code carrier.
• the image of the code pattern reflected by the mirror 20 is received by at least one collimator device 22.
• the collimator device 22 is a two-dimensionally arranged ordered group of detector cells 23. These individually scannable detector cells are used to detect a two-dimensional shift of the code pattern image from a reference position. With this two-dimensional displacement, changes in position of the mirror 20 are detected both in azimuthal and in a second angular dimension. The combined detection of the azimuth and the elevation of an object connected to the mirror 20 or its targeted tracking is therefore possible on the basis of measured deviations.
• FIG. 5 shows a preferred exemplary embodiment based on the beam path in detail.
• the optics 40 of the transmission telescope define the transmission axis A, in the extension of which there is a code carrier 41 in the image plane which is provided with a bar code 42.
• the bar code consists, for example, of a sequence of vertically running bars arranged next to one another, the bar width and the lateral spacing of the bars serving as direction-specific coding parameters.
• the combination of the bars of the code, which are arranged on a scale, contain information about the exact position along the "scale". Each area selected arbitrarily from the "scale” allows the precise determination of the area position on the "scale” if the code is known.
• the code is applied to a transparent code carrier 41.
• the code carrier 41 is illuminated by a lamp 43 located behind it. The higher the demands on the measuring accuracy of the device, the finer the subdivision is to select the code on the code carriers 41, and the shorter the 'Wellen ⁇ length of the illumination verv / emitted light source 43.
• the receiving optics 45 On the receiver side there is the receiving optics 45, the axis B of which is angularly offset from the transmitting axis A by the angle 'delta'.
• the code 42 of the code carrier 41 emitted by the transmitting optics 40 is imaged in a detector device 46, which is arranged in the image plane of the receiver optics 45.
• the code on the detector device 46 is also angularly offset, which is detected by the individual detector cells belonging to the detector group.
• the signals supplied by the detector cells are passed on to a signal processing device 50.
• the position or the deviations of the code pattern on the transmitter side and of the code pattern image on the receiver side are shown for the various practical cases in FIGS. 6A to 6C. 6A, the transmitting and receiving sides are in perfect alignment.
• the code pattern image captured by the evaluation device is symmetrical about the center line Y and this state can be recognized by the coincidence of the zero line of the code image with the center line Y used as a reference.
• the axis of the transmitting optics is angularly offset from the axis of the receiving optics by the amount 'delta'. This state is indicated by the fact that the light intensity distribution of the code pattern in the image plane of the receiving optics is distributed symmetrically around the center line Y, but that the code itself appears offset to the side. The lateral offset of the code is given by the angular offset 'delta' multiplied by the focal length of the receiving optics.
• the axis of the transmitting optics runs parallel to that of the receiving optics, but is laterally offset by a certain amount. This state is recognized in the receiver by the fact that the “intensity distribution of the code pattern is laterally offset, but the code itself is not offset.
• the signal processing device 50 contains an amplifier 51, a sample and hold circuit 52 and a downstream analog / digital converter 56, the output of which is led to a computer 53.
• a position sensor 57 is connected to the computer, with which a starting or reference position is set.
• the computer compares the values obtained from the analog / digital converter with the values stored in a reference memory 54 and displays the result on a display device 55.
• the display on the display device 55 can take place directly in angle values, that is to say indicate the angle 'delta' in degrees or degrees.
• the display can also be in coded or any other form.
• the coded signal can serve as a tracking signal for one of the two telescope devices in order to set them to a predetermined angular position.
• a further angle for example an associated elevation angle
• a two-dimensional code pattern ver / ends. This is evaluated by the receiving device according to the same principles as described for the one-dimensional code.
• One- or two-dimensional spatial patterns were mentioned as code patterns. Instead, time-coded patterns can also be used, for which the transmitting and receiving devices are to be equipped with appropriate means for processing the signals staggered over time. In the context of the present invention, all such codes are understood by the term “direction-specific code pattern”.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Length Measuring Devices By Optical Means (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

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Family Applications (1)

Country Status (7)

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• 1985
  • 1985-10-21 CH CH4524/85A patent/CH670907A5/de not_active IP Right Cessation
• 1986
  • 1986-01-14 DE DE19863600859 patent/DE3600859A1/de not_active Withdrawn
  • 1986-03-13 FR FR8603569A patent/FR2588952A1/fr not_active Withdrawn
  • 1986-10-17 IL IL80358A patent/IL80358A0/xx unknown
  • 1986-10-20 WO PCT/CH1986/000147 patent/WO1987002450A1/de not_active Application Discontinuation
  • 1986-10-20 EP EP86905713A patent/EP0243385A1/de not_active Withdrawn
  • 1986-10-20 JP JP61505371A patent/JPS63501592A/ja active Pending

Non-Patent Citations (1)

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