WO1992015839A1 - Appareil et procede de mesure de l'ecart entre point de reference et une donnee de reference - Google Patents

Appareil et procede de mesure de l'ecart entre point de reference et une donnee de reference Download PDF

Info

Publication number
WO1992015839A1
WO1992015839A1 PCT/GB1992/000427 GB9200427W WO9215839A1 WO 1992015839 A1 WO1992015839 A1 WO 1992015839A1 GB 9200427 W GB9200427 W GB 9200427W WO 9215839 A1 WO9215839 A1 WO 9215839A1
Authority
WO
WIPO (PCT)
Prior art keywords
aircraft
deviation
datum
image
reference point
Prior art date
Application number
PCT/GB1992/000427
Other languages
English (en)
Inventor
Eric George
Original Assignee
Hunting Aviation Services Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hunting Aviation Services Limited filed Critical Hunting Aviation Services Limited
Publication of WO1992015839A1 publication Critical patent/WO1992015839A1/fr
Priority to GB9318643A priority Critical patent/GB2271238B/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
    • G01S1/02—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves
    • G01S1/022—Means for monitoring or calibrating
    • G01S1/024—Means for monitoring or calibrating of beacon transmitters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C1/00—Measuring angles
    • G01C1/02—Theodolites
    • G01C1/04—Theodolites combined with cameras
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C11/00—Photogrammetry or videogrammetry, e.g. stereogrammetry; Photographic surveying
    • G01C11/04—Interpretation of pictures
    • G01C11/06—Interpretation of pictures by comparison of two or more pictures of the same area
    • G01C11/28—Special adaptation for recording picture point data, e.g. for profiles

Definitions

  • the present invention relates to an an apparatus and method for measuring deviation from a datum of a reference point on an object such as an aircraft.
  • ILS instrument landing system
  • LS is a radio-based system which provides lateral and vertical guidance to the pilot.
  • an ILS comprises two narrow radio beams transmitted from the airfield.
  • Each radio beam has a different carrier frequency but is amplitude modulated at two different frequencies, typically 90 Hz and 150 Hz for both beams.
  • the aircraft is equipped with on-board instrumentation for receiving signals the radio beam signals.
  • One of the beams is used for determining left or right horizontal deviation of the aircraft from the optimum flight path and is transmitted from the far end (stop end) of the runway. This beam is called the localiser or azimuth beam.
  • the other beam is used to determine whether the aircraft is above or below the optimum flight path and is transmitted from the near end (start or touch-down end) of the runway. This beam is called the azimuth or glide slope beam.
  • Each beam is complex so that when the aircraft is flying down the ideal (say horizontal) centre line, the modulation intensity of the 90 Hz and 150 Hz modulations detected by the on-board instruments from the localiser beam is equal. If the aircraft is to the left or right, the detected modulation intensity of the respective modulations will be out of balance. Since the beam is specially calibrated, the direction and amount by which the modulation intensity is out of balance is used to indicate the direction and degree to which the aircraft is to the left or right of the flight path. The glide slope beam is used in like fashion.
  • a known technique for calibrating the beams utilises a theodolite telescope situated in front of the localiser beam or beside the glideslope beam.
  • the angular position of an aircraft flying down the beam centres is monitored by tracking it with the theodolite telescope, keeping the aircraft centred in the field of view.
  • this system is dependent upon the skill of the operator and unacceptable errors can occur.
  • the measured angle is transmitted to the aircraft where it is automatically compared with the deviation from the beam measured bv the ILS 'instruments on-board.
  • An aim of the present invention is, therefore, to provide an imaging apparatus and method of tracking an aircraft to within a few seconds of arc to enable accurate calibration of the ILS system.
  • the present invention also has application in measuring the movement of structures under adverse conditions.
  • a surveyor with one or more theodolites is sent to a site where adverse condition may be expected.
  • the surveyor uses laser range finder and the angles measured by the theodolite telescope to measure the movement of the structure. Disadvantages with this system include the need to anticipate the adverse conditions, the measured results depend on the skill and accuracy of the surveyor and the surveyor has to be physically present during such conditions.
  • the further aim of this present invention is to provide an imaging apparatus and method of tracking a moving object which substantially overcomes these disadvantages.
  • the present invention has a further application in the use of measuring structures during the manufacture of the assembly of these structures.
  • many large structures such an aircraft fuselage, wing or a car body has been designed by computer related (CAD) system. Before using the prototype or initial structure, it is necessary to measure them accurately so as to check that the structure do indeed meet the specification and requirements required.
  • CAD computer related
  • the structure is typically measured by installing a number of theodolites equipped with laser distance measuring apparatus around structure at very accurate positions.
  • the theodolites are usually mounted on a very large rolled steel joist jig.
  • Two or more theodolites are then used to measure the angle from the theodolite to a narticular reference point.
  • the reference points are varied and angular measurements are taken in each case. This is then repeated either manually or using servo-controlled theodolites for other reference positions over the whole of the structure.
  • a further aim of the present invention is therefore to provide a imaging apparatus and method of accurately measuring a structure more quickly known hitherto.
  • the present invention provides a method of measuring the deviation from a datum of a reference point on an object within an image, the method comprising:
  • the invention further provides an apparatus for measuring the deviation from a datum of a reference point on an object within an image, the apparatus comprising:
  • an electronic image detector coupled to the theodolite telescope for viewing the image therethrough to produce a signal representative of said image
  • the term "theodolite telescope” means a telescope or other focussing system of an appropriate focal length having a field of view reference such as a graticule and means for indicating in what direction the telescope is pointing.
  • an electronic image detector may be of any suitable type, such as a hot-cathode television camera or a solid state (eg. CCD) TV camera. Where high resolution is not required, it could even be a simple two-dimensional array of photodiodes, or the like.
  • the datum may for example be a line, the object moving and the theodolite telescope is used to track the object whilst staying aligned with the datum line.
  • the object is an aircraft.
  • the reference point is then signified by a light source on the aircraft.
  • the calculated deviation may be the horizontal or vertical deviation of aircraft position from a predetermined flight path.
  • the calculated deviation may be used to determine the directional error of a radiofrequency beam of an instrument landing system.
  • the calculated deviation is transmitted to the aircraft and compared on-board the aircraft with the deviation of the aircraft from the beam.
  • the distance of the aircraft from the runway is measured, for example using a receiver of a satallite navigation system (such as GPS). Most preferably, this is done both on-board the aircraft and at the location of the theodolite telescope.
  • a receiver of a satallite navigation system such as GPS
  • the signal from the image detector may be processed to compare the brightness of pixels of the detector to distinguish the reference point.
  • the field of spatial discrimination of the image detector may be restricted in a direction generally parallel to or along the datum line.
  • the datum may be a line
  • the datum may be a predetermined point.
  • the predetermined point may for example be a point on a structure.
  • the structure could be a manufactured article and the calculated deviation is used to determine manufacturing accuracy.
  • the structure is preferably also viewed with a second theodolite telescope and the reference point is a moving point indicated by a scanning laser beam.
  • the observed structure could also be a bridge, edifice or other exterior structure and the calculated deviation is used to determine movement d .e to weather conditions or other advance conditions such as earth tremor.
  • the present invention also provides a theodolite telescope whose optical output is coupled to an opto-electronic detector comprising a two-dimensional array of sensors each arranged for generating a pixel data output representative of light intensity from a different part of the field of view of the theodolite telescope.
  • a method according to the present invention of tracking a moving object having a light emitting element may comprise using at least one imaging apparatus in accordance with the preceding paragraph, comprising arranging the object to be in the field of view and then making repeated measurements of the angular position of the light-emitting element.
  • FIG 1 shows the operation of an ILS system
  • Figure 2 shows how horizontal flight path error is measured in accordance with the present invention
  • Figure 3 shows how vertical glide path error is measured in accordance with the present invention
  • Figure 4 is a schematic diagram of the apparatus and, method of tracking an aircraft, according to a preferred embodiment of the present invention.
  • Figure 5 is a schmematic diagram of a second embodiment of the present invention for determining movement of a structure under adverse conditions; and
  • Figure 6 is a schematic diagram of a third embodiment of the present invention for determining accuracy in a manufactured structure.
  • Figure 2 shows an image of an incoming aircraft 11 as seen within the field of view 13 of theodolite telescope.
  • the telescope has a vertical graticule 15 and a horizontal graticule 17.
  • the line 21 indicates the ideal centre line of the ILS localiser beam.
  • the vertical graticule 15 is lined with this ideal centre line and the theodolite is moved up and down in the direction of the arrow A until the aircraft 11 comes within the field of use.
  • the aircraft is then tracked by moving the theodolite telescope with the vertical graticule aligned with the vertical centre-line as indicated by the arrow A.
  • the horizontal offset x is measured by the system which can be used to calculate the angular deviation ⁇ measured from ground zero 23 at the far end of the runway.
  • reference numeral 25 denotes the idealised centre line of the glide slope beam. This is typically at an angle of 3 * relative to the ground.
  • the theodolite telescope is positioned to the side of the runway and the horizontal graticule 17 is aligned with the idealised vertical centre line 25.
  • the theodolite telescope is moved with the horizontal graticule always in line with the idealised vertical centre line as indicated by the arrow B until the aircraft comes into the field view and the aircraft is then tracked keeping the horizontal graticule and ideal vertical centre line always aligned.
  • the vertical offset y is measured and used to calculate the vertical offset as measured from the relevant ground zero at the beginning of the runway.
  • the theodolite telescope 31 is coupled to an opto-electronic detector 33.
  • the theodolite comprises a Wild Leitz (Leica) T.1, 000 electronic theodolite which has a telescope capable of 30 times magnification with a field of view of 27 meters at a distance of 1,000 meters. Thus the field of view is approximately 1.5 * .
  • the vertical and horizontal orientation of the telescope can be read-out to within 0.1 second of arc.
  • An opto-electronic detector 35 is installed in place of the normal viewing eye piece of the telescope.
  • a Fairchild Western dot matrix CCD industrial television camera having an 483 x 378 pixel array (182, 574 pixels).
  • a reference point aircraft is fitted with a front-mounted light source 37.
  • the light source is detected by the camera.
  • the displacement of the light source 8 is measured with respect a reference point of the camera 4.
  • the output of the CCD camera is fed into an electronic circuit 39, together with the orientation of the theodolite telescope.
  • the electronic circuit 39 comprises an image capture circuit 41 for capturing image frames corresponding to the image seen by the camera at predetermined intervals.
  • Electronic data corresponding into an image frame are stored in a RAM (Random Access Memory) 43 connected to an output of the image capture circuit. These are over-written each time that a new frame is grabbed by the image capture circuit.
  • the remainder of the electronic circuit 43 may comprise a microcomputer with appropriate input and output interfaces.
  • the units denoted in Figure 4 by the reference numerals 45-51 may be considered as steps in a program executed by a computer program. Alternatively, these may be carried out by hard-wired discrete electronic circuitry and so reference numerals may be considered as individual electronic "means". In the following description, they will be referred to as steps in a computer calculation.
  • the contents of the RAM file are scanned in a step 45 by microprocessor circuitry to identify the position of the light source in the field of view of the camera.
  • a step 47 a pixel count is undertaken to determine image position and in a step 49, this is translated to an angular position at step 51.
  • the theodolite telescope is set-up in front of a calibration object such as a point light source.
  • the graticule is centred on the light source.
  • the theodolite angle is noted.
  • the light source is then moved to (say) the top right hand quadrant within the theodolite' s field of view.
  • the graticule is then re-centred on the light source.
  • the circuitry counts the number of pixels traversed by source within the field of view in both the vertical and horizontal directions.
  • the light source is then moved to (say) the bottom left quadrant and the process is re ⁇ eated. Since the light source has moved through known distances in the horizontal and vertical directions and is at a known distance from the telescope, an algorithm can then easily be constructed to relate number of pixels displacement from the graticule to linear or angular displacement for future measurements.
  • means 53 causes a circuit 55 to trigger capture of another image frame by the image capture circuit 41.
  • the measured angle is transmitted to the aircraft by a transmitter 57.
  • the ILS receiver determines the deviation of the aircraft position from the actual ILS beams to indicate to the pilot on a display, which way to fly the aircraft to correct apparent flight path error.
  • the on-board instrumentation of the system according to this invention also receives the signal from transmitter 57, indicating the deviation of the aircraft from the ideal flight path. Both deviations can be plotted on a chart recorder in the aircraft. If the ILS beams are correctly oriented, the plotted deviations should be the same as each other.
  • the deviations are also stored in digital form in the aircraft instrumentation for final detailed checking on the ground.
  • the ILS beams should be checked periodically for long term stability. In that way, even if one or both beams has a small directional error but is still within the bounds of specified accuracy, long term drift can be detected and so corrected-for.
  • the variation of the aircraft from the ideal flight path may be displayed to the pilot in the same way as the ILS data. In that case the pilot can correct his course to fly down the ideal flight path rather than that indicated by the ILS beams.
  • Data from each of the camera pixels are thus stored frame by frame in the RAM.
  • the value from each pixel is assigned an eight bit number (0 to 255) representing the light detected on a grey scale from black to white.
  • the stored data may be considered as a table 27 of relevant values.
  • the brightest area (highest values) are identified.
  • the number of pixels which are at least a predetermined percentage brighter than the background (rest of the field of view) is counted.
  • the brightest area is considered a false target.
  • the brightest area is considered to correspond to a genuine target.
  • the centre of the brightest area is then identified and the pixel at that centre is used to calculate the displacement.
  • the predetermined percentage used is 30% and the threshold for number of pixels of at least 30% brighter than background is 1, 000.
  • the theodolite In use, although the relevant part of the graticule is aligned with the ideal datum (flight path line), the theodolite is moved in the direction of the datum line until the aircraft comes into the field of view.
  • the scene picked up by the CCD camera is viewed on the screen of a TV monitor 57 which is connected to the image capture circuit.
  • the target (bright spot) identification procedure described above is initiated.
  • the circuit 39 puts a black spot on the screen in a position corresponding to the assumed target. If the operator decides this is correct, a button is pressed to verify it. Thereafter, the field of scanned pixels is restricted in the direction along the datum line but is maintained at full width in the direction orthagonal to the datum line. This is because once the aircraft is located, it will move very little within the field of view in the direction of the datum line and in any case, the operator will then track the aircraft with the theodolite telescope along the line. However, full resolution will be required to detect drift in the direction in which deviation is being determined.
  • One or more coloured filters may be placed over the front of the theodolite telescope to enhance image contrast.
  • a polarising filter may be placed over the front of the telescope to discriminate against light reflected from clouds.
  • the contents of the RAM is scanned to identify the data having the highest number and consequently indentifies that diode which has detected the most light.
  • the circuit then calculates the position of the brightest point with respect a reference point which in the preferred embodiment is the centre of the camera (step 47).
  • step 49 the number of pixels the brightest spot is displaced from the centre is counted and used to calculate the angular displacement from the centre. As stated above the calculated angular displacement is then used in step 24 to correct the angular displacement detected.
  • the camera provides image frames every 200 to 500 milliseconds. That is to say at least 2 frames per second.
  • the corrected angular position transmitted to the aircraft can also be updated again at a rate of at least 2 frames per second.
  • Aircraft position from the runway is normally determined by on-board detection of radio Lignals from marker beacons. However, for the accuracy required for the system of the present embodiment, this is determined using the global positioning satellite (GPS) system.
  • GPS uses signals from three or more satellites to determine the position of a receiver relative to the ground.
  • FIG. 5 of the present invention there is shown another embodiment in which movement of a structure under adverse conditions such as high winds is monitored.
  • a bridge 101 has a painted mark 103 on part of the structure 105 which is subject to movement in strong wind.
  • a theodolite telescope 107 is mounted on a secure base 109 in a position where it is protected from the wi d.
  • the theodolite telescope is provided with a CCD image detector 111 connected to a circuit 113, substantially as described in the last embodiment.
  • the field of view 115 of the telescope is trained on the painted spot 103 such that the spot is on the centre of the graticule.
  • the orientation of the theodolite telescope is then securely fixed. Thus, it is aligned with a datum point.
  • the degree of movement of the bridge can be calculated by the circuitry.
  • the circuitry may be in a remote location such as a control room where the movement of the bridge can be monitored in comfort, without the need to send anybody out to the site of the bridge. If the degree of movement exceeds a certain level, a decision can be taken to close the bridge to traffic.
  • FIG. 6 Another embodiment is shown in Figure 6, whereby manufacturing accuracy may be determined.
  • a prototype manufactured object in the form of a cover 201 for an aero engine.
  • This may for example have been designed using a CAD system, or designed and formed using CAD-CAM.
  • CAD means computer-aided-design and CAM stands for computer-aided-manufacture.
  • an area of interest 203 on the engine cover is scanned in a raster pattern 205 by a beam 207 from a scanning laser 209.
  • the area 203 is in the field of view of two theodolite telescopes 211, 213 provided with respective image detectors 215, 217 connected to an appropriate electronic circuit 219, similar to those described in res ⁇ ect of the previous embodiments.
  • the telescopes are angled relative to one another,, preferably such that their fields of view are angled at least 30 * relative to each other.
  • the centre cross of both graticules are aligned on the same reference point on the engine cover and their fields of view are substantially coincident on the surface of the cover.
  • the laser beam is first used to irradiate a point within the area 203 and identified as a target in the way mentioned previously.
  • the telescopes are also calibrated in terms of the distance traversed by the scanning beam in the same way as performed in the first embodiment.
  • the precise distance from the telescopes (z) can be determined.
  • the relative angular orientation between the telescopes is known, as is their distance apart and the distance of each from the engine cover. Therefore, it becomes a simple matter to program the circuit 219 to determine the profile of the cover from the differences in the position of the scanning beam as perceived by the detectors 215 and 217.
  • a model may be produced corresponding to an article to be manufactured. Scanning it with a laser beam and observing the scanning pattern with two relatively angled theodolite telescopes exactly as in the embodiment of Figure 6 will yield data corresponding to its precise shape. These data can then be fed into a I S
  • CAD or CAD-CAM system to produce a design for manufacturing the real article corresponding to the model.
  • the design may also be scaled-up or down in size relative to the model.

Landscapes

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

Abstract

Appareil et procédé de mesure de l'écart entre un point de référence et une donnée de référence, utilisant un télescope à théodolite (31) pourvu d'un détecteur d'image électronique (35). Le télescope à théodolite est initialement aligné avec la donnée de référence. Les signaux émis par le détecteur sont traités par un circuit électronique (39) de manière à calculer l'écart. La donnée de référence peut être une ligne telle qu'une trajectoire de vol idéale d'un avion muni d'une lumière qui sert de point de référence. La donnée de référence peut être constituée également par un point, par exemple sur une structure se déplaçant sous l'effet de forts coups de vent. On peut aussi déterminer le profil d'un objet en utilisant deux de ces télescopes à théodolite pourvus de détecteurs reliés à un circuit électronique.
PCT/GB1992/000427 1991-03-11 1992-03-11 Appareil et procede de mesure de l'ecart entre point de reference et une donnee de reference WO1992015839A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB9318643A GB2271238B (en) 1991-03-11 1993-09-08 Apparatus and method for measuring deviation of an aircraft from a flight path

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9105107.8 1991-03-11
GB919105107A GB9105107D0 (en) 1991-03-11 1991-03-11 Imaging apparatus and method of tracking a moving object

Publications (1)

Publication Number Publication Date
WO1992015839A1 true WO1992015839A1 (fr) 1992-09-17

Family

ID=10691349

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1992/000427 WO1992015839A1 (fr) 1991-03-11 1992-03-11 Appareil et procede de mesure de l'ecart entre point de reference et une donnee de reference

Country Status (3)

Country Link
AU (1) AU1354592A (fr)
GB (2) GB9105107D0 (fr)
WO (1) WO1992015839A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2280563A (en) * 1993-06-02 1995-02-01 Marconi Gec Ltd Apparatus for detecting and indicating the position of a source of transient optical radiation
US7339611B2 (en) 2000-05-20 2008-03-04 Trimble Jena Gmbh Method and arrangement for carrying out an information flow and data flow for geodetic instruments
CN108303062A (zh) * 2016-12-27 2018-07-20 株式会社和冠 图像信息处理装置及图像信息处理方法
CN110114246A (zh) * 2016-12-07 2019-08-09 乔伊森安全系统收购有限责任公司 3d飞行时间有源反射感测系统和方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2430851A1 (de) * 1974-06-27 1976-01-15 Werner Dipl Ing Aicher Koordinaten-messung mittels photogrammetrischer methoden
WO1981003698A1 (fr) * 1980-06-12 1981-12-24 W Bryan Procede et dispositif permettant le controle d'un mouvement
JPS59166804A (ja) * 1983-03-14 1984-09-20 Hitachi Ltd 船の動揺検知装置
GB2165415A (en) * 1984-10-03 1986-04-09 Standard Telephones Cables Plc Checking of radio navigation aids for aircraft
GB2183841A (en) * 1985-11-29 1987-06-10 Lkb Int Surveying method
US4758840A (en) * 1986-03-11 1988-07-19 Centre National D'etudes Spatiales Means for calibrating the elevation and azimuth angles of the scan axis of an antenna
DE3929581A1 (de) * 1989-09-06 1991-03-07 Bodenseewerk Geraetetech Einrichtung zur registrierung von flugwegen und flugmanoevern von flugzeugen

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2430851A1 (de) * 1974-06-27 1976-01-15 Werner Dipl Ing Aicher Koordinaten-messung mittels photogrammetrischer methoden
WO1981003698A1 (fr) * 1980-06-12 1981-12-24 W Bryan Procede et dispositif permettant le controle d'un mouvement
JPS59166804A (ja) * 1983-03-14 1984-09-20 Hitachi Ltd 船の動揺検知装置
GB2165415A (en) * 1984-10-03 1986-04-09 Standard Telephones Cables Plc Checking of radio navigation aids for aircraft
GB2183841A (en) * 1985-11-29 1987-06-10 Lkb Int Surveying method
US4758840A (en) * 1986-03-11 1988-07-19 Centre National D'etudes Spatiales Means for calibrating the elevation and azimuth angles of the scan axis of an antenna
DE3929581A1 (de) * 1989-09-06 1991-03-07 Bodenseewerk Geraetetech Einrichtung zur registrierung von flugwegen und flugmanoevern von flugzeugen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 009, no. 020 (P-330)26 January 1985 ( HITACHI SEISAKUSHO KK ) 20 September 1984 & JP,A,59 166 804 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2280563A (en) * 1993-06-02 1995-02-01 Marconi Gec Ltd Apparatus for detecting and indicating the position of a source of transient optical radiation
US7339611B2 (en) 2000-05-20 2008-03-04 Trimble Jena Gmbh Method and arrangement for carrying out an information flow and data flow for geodetic instruments
CN110114246A (zh) * 2016-12-07 2019-08-09 乔伊森安全系统收购有限责任公司 3d飞行时间有源反射感测系统和方法
CN110114246B (zh) * 2016-12-07 2022-03-01 乔伊森安全系统收购有限责任公司 3d飞行时间有源反射感测系统和方法
US11447085B2 (en) 2016-12-07 2022-09-20 Joyson Safety Systems Acquisition Llc 3D time of flight active reflecting sensing systems and methods
CN108303062A (zh) * 2016-12-27 2018-07-20 株式会社和冠 图像信息处理装置及图像信息处理方法

Also Published As

Publication number Publication date
AU1354592A (en) 1992-10-06
GB9318643D0 (en) 1994-01-05
GB2271238A (en) 1994-04-06
GB2271238B (en) 1995-04-05
GB9105107D0 (en) 1991-04-24

Similar Documents

Publication Publication Date Title
US9958268B2 (en) Three-dimensional measuring method and surveying system
EP2765388B1 (fr) Contrôleur de terrain mobile destiné à arpentage et commande à distance
US6031606A (en) Process and device for rapid detection of the position of a target marking
CN101960256B (zh) 测量仪器的自动校准
US5087916A (en) Method of navigation
EP3591336B1 (fr) Procédé et programme d'arpentage
US6310644B1 (en) Camera theodolite system
US5136297A (en) Method for navigation and updating of navigation for aircraft
US5208418A (en) Aligning method for a fire control device and apparatus for carrying out the alignment method
US4758840A (en) Means for calibrating the elevation and azimuth angles of the scan axis of an antenna
CN111044990B (zh) 机载激光雷达光束指向标定方法、系统及激光光斑探测器
JPH0124275B2 (fr)
US3896432A (en) Perspective radar airport recognition and landing guidance system
CN109186944A (zh) 机载多光轴光学载荷光轴一致性标校方法
CA3112187C (fr) Cible multidimensionnelle optique et procede de detection et de suivi d'objets multiples
CN108896169A (zh) 一种助航灯光强实时高速检测系统
EP0597715A1 (fr) Etalonnage automatique d'un système d'atterrissage
CN104713520B (zh) 对大口径光学系统u型机动转台的0位进行确定的方法
WO1992015839A1 (fr) Appareil et procede de mesure de l'ecart entre point de reference et une donnee de reference
EP1340999A1 (fr) Procédé et dispositif pour détecter l'orientation d'un objet
EP2240741B1 (fr) Localisation d un instrument de relevé géodésique par rapport à un repère au sol
KR100913165B1 (ko) 이동체의 위치 검출 장치 및 방법
EP1059507B1 (fr) Système d'étalonnage pour des systèmes de capteurs optoélectroniques
CN115359048B (zh) 一种基于闭环跟瞄的实时动态对准测量方法及跟瞄装置
EP1340998A1 (fr) Procédé et dispositif pour détecter l'orientation d'un objet

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AT AU BB BG BR CA CH CS DE DK ES FI GB HU JP KP KR LK LU MG MN MW NL NO PL RO RU SD SE US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE BF BJ CF CG CH CI CM DE DK ES FR GA GB GN GR IT LU MC ML MR NL SE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA