WO1989007771A1 - Optical tracking instrument - Google Patents
Optical tracking instrument Download PDFInfo
- Publication number
- WO1989007771A1 WO1989007771A1 PCT/EP1988/001161 EP8801161W WO8907771A1 WO 1989007771 A1 WO1989007771 A1 WO 1989007771A1 EP 8801161 W EP8801161 W EP 8801161W WO 8907771 A1 WO8907771 A1 WO 8907771A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- unit
- signal
- distance
- energy
- signal evaluation
- Prior art date
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
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
- G01S7/497—Means for monitoring or calibrating
-
- 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
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
Definitions
- the invention relates to a device for optical distance measurement by means of a measuring device according to the preamble of claim 1.
- DE-PS 3020996 discloses a device for determining the triggering distance of a missile moving towards a target, both a precise determination of the triggering distance and its use regardless of weather conditions, such as Smoke, fog, etc. allowed.
- the energy contents of the integrators connected downstream by distance gates are fed in, while an evaluation unit checks the level of the integrator voltages.
- filters are used as attenuators to regulate the dynamic range or a regulated, optical attenuator plate is positioned in front of the detector (DE-PS 3335869).
- the object of the invention is to create a measuring device, primarily for distance warning systems (AUS), which not only further increases the dynamic range previously achieved, but also improves eye safety and the signal / noise ratio and minimizes the power consumption of the measuring system.
- AUS distance warning systems
- Figure 1 is a block diagram of an embodiment in a schematic representation.
- 2b shows a diagram relating to the excitation of the energy in poor visibility conditions.
- the device for optical distance measurement outlined in FIG. 1 is composed of a transmitter 11 and a receiver 13, to which a device for signal evaluation 14 is assigned.
- a pulse or CW laser, the emitted beam 12 of which is reflected by a target or obstacle, etc., is preferably used as the transmitter 11 and is received by the receiver as a detected signal 12a and fed to the unit for signal evaluation 14.
- This is assigned a device for signal evaluation 15, a measured variable display device 17 and a signal unit 18.
- the former 15 carries out an evaluation with respect to distance, amplitude and eye safety, either individually or as a whole, and forwards the evaluation result as a signal to an energy control unit 16, which accordingly regulates the transmission beam 12 of the transmitter 11.
- the output power and / or the output energy of the transmitter laser is regulated to a minimum by the energy control unit 16 in accordance with the distance of a target detected by the receiving unit 13 through the reflected beam 12a, because good visibility conditions etc. reduce the laser output power or the laser output energy.
- the proposed distance measuring device 10 is designed such that its transmitter unit 11 is automatically switched off when a shortfall in a predetermined minimum distance is detected and that the signal evaluation 14 is also undercut when the predetermined minimum measuring conditions are undershot and / or one of them is detected Misinterpretation leading measurement condition controls the signal unit 18, through which an optical or acoustic warning signal is given.
- the optical warning signal can optionally also be given by the measurement variable display device 17.
- the signal unit 18 additionally performs a switching function, for example activating the low beam or the fog lights or the windshield wipers.
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Optical Radar Systems And Details Thereof (AREA)
Abstract
In an optical tracking device, the output power and/or output energy of the output signal (12) from the emitter (1) are adaptively controlled in accordance with the measurement conditions determined by the receiving unit (13) from the backscattered, detected signal. An embodiment is described and illustrated in the figures of the drawing.
Description
Optisches AbstandsmeßgerätOptical distance measuring device
Die Erfindung betrifft eine Einrichtung zur optischen Abstandsmessung mittels eines Meßgerätes gemäß dem Gattungsbegriff des Anspruchs 1.The invention relates to a device for optical distance measurement by means of a measuring device according to the preamble of claim 1.
Solche Einrichtungen sind in verschiedenen Ausführungsformen - auch von der Anmelderin - bekannt. So ist beispielsweise zur Erzielung eines höheren Dynamikbereiches solcher Geräte in der DE-PS 3020996 eine Einrichtung zur Bestimmung der Auslöseentfernung von einem sich auf ein Ziel zubewegenden Flugkörper offenbart, die sowohl eine genaue Fest¬ stellung der Auslöseentfernung als auch deren Einsatz unabhängig von Witterungsbedingungen, wie Rauch, Nebel etc., gestattet. Hierzu werden die Energieeinhalte der durch Entfernungstore ausgefilterten Impulsan¬ teile nachgeschalteten Integratoren zugeleitet, während eine Auswerte¬ einheit die Integratorspannungen ihrer Höhe nach überprüft.Such devices are known in various embodiments - also by the applicant. For example, in order to achieve a higher dynamic range of such devices, DE-PS 3020996 discloses a device for determining the triggering distance of a missile moving towards a target, both a precise determination of the triggering distance and its use regardless of weather conditions, such as Smoke, fog, etc. allowed. For this purpose, the energy contents of the integrators connected downstream by distance gates are fed in, while an evaluation unit checks the level of the integrator voltages.
Bei anderen bekannten Einrichtungen werden zur Regelung des Dynamikbe¬ reiches Filter als Abschwächer eingesetzt oder vor den Detektor eine geregelte, optische Abschwächerplatte positioniert (DE-PS 3335869).In other known devices, filters are used as attenuators to regulate the dynamic range or a regulated, optical attenuator plate is positioned in front of the detector (DE-PS 3335869).
Alle diese Einrichtungen verbessern lediglich den Dynamikbereich in einem gewissen Umfang und erfordern mechanisch in den Strahlengang einschiebbare Graufilter. Dadurch jedoch arbeitet das Meßgerät zwangs¬ läufig für zahlreiche Einsatzfälle zu langsam.All of these devices only improve the dynamic range to a certain extent and require gray filters that can be mechanically inserted into the beam path. As a result, however, the measuring device inevitably works too slowly for numerous applications.
Der Erfindung liegt die Aufgabe zugrunde, vorwiegend für Abstandswarn- systeme (AUS) ein Meßgerät zu schaffen, das nicht nur den bisher er¬ reichten Dynamikbereich weiter erhöht, sondern auch die Augensicherheit und das Signal/Rauschverhältnis verbessert sowie die Leistungsaufnahme des Meßsystems minimiert.
Diese Aufgabe wird durch die im Anspruch 1 aufgeführten Maßnahmen in überraschend einfacher Weise gelöst. In den Unteransprüchen sind Ma߬ nahmen zur Weiterbildung und Ausgestaltung angegeben und in der nach¬ folgenden Beschreibung st ein Ausführungsbeispiel erläutert und in den Figuren der Zeichnung skizziert. Es zeigen:The object of the invention is to create a measuring device, primarily for distance warning systems (AUS), which not only further increases the dynamic range previously achieved, but also improves eye safety and the signal / noise ratio and minimizes the power consumption of the measuring system. This object is achieved in a surprisingly simple manner by the measures listed in claim 1. In the subclaims, measures for further development and refinement are specified and an exemplary embodiment is explained in the following description and outlined in the figures of the drawing. Show it:
Fig. 1 ein Blockschaltbild eines Ausführungsbeispiels in schematischer Darstellung;Figure 1 is a block diagram of an embodiment in a schematic representation.
Fig. 2a ein Diagramm bezüglich der Herabregelung der Energie bei hohem Signal im Nahberei h;2a shows a diagram relating to the reduction of the energy with a high signal in the near range h
Fig. 2b ein Diagramm bezüglich der Hinaufrege!ung der Energie bei schlechten Sichtbedingungen.2b shows a diagram relating to the excitation of the energy in poor visibility conditions.
Die in Fig. 1 skizzierte Einrichtung zur optischen Abstandsmessung setzt sich aus einem Sender 11 und einem Empfänger 13 zusammen, denen eine Einrichtung zur Signalauswertung 14 zugeordnet ist. Als Sender 11 dient vorzugsweise ein Puls- oder CW-Laser, dessen ausgesendeter Strahl 12 von einem Ziel oder Hindernis etc. reflektiert wird und als detektiertes Signal 12a vom Empfänger aufgenommen und der Einheit zur Signalaus¬ wertung 14 zugeleitet wird. Dieser ist einmal eine Einrichtung zur Signalbewertung 15, eine Meßgrößen-Anzeigeeinrichtung 17 und eine Signaleinheit 18 zugeordnet. Erstere 15 führt eine Bewertung in bezug auf Abstand, Amplitude und Augensicherheit, entweder einzeln oder insgesamt durch und gibt das Bewertungsergebnis als Signal einer Ener¬ giesteuereinheit 16 weiter, die dementsprechend den Sendestrahl 12 des Senders 11 regelt. Das heißt: Die Ausgangsleistung und/oder die Aus¬ gangsenergie des Senderlasers wird entsprechend dem von der Empfangsein¬ heit 13 durch den reflektierten Strahl 12a detektierten Abstand eines Zieles durch die Energiesteuereinheit 16 auf ein Minimum geregelt, weil gute Sichtbedingungen etc. eine Reduzierung der Laserausgangsleistung bzw. der Laserausgangsenergie zulassen. Dadurch wird die Augensicherheit erheblich verbessert. Liegen nun schlechte Sichtverhältnisse vor oder verschlechtern sich die gegebenen Sichtverhältnisse, beispielsweise
durch beginnenden Regen, Rauch oder aufziehenden Nebel, so stellt dies die Einheit zur Signalauswertung 14 im Zusammenhang mit der Einrichtung zur Signalbewertung 15 fest und leitet das entprechend bewertete Empfangssignal 12a der Energiesteuerung 16 zu, die nun den Lasersende¬ strahl 12 auf ein entsprechendes Maximum höher regelt. Dieses Maximum bezieht sich jeweils auf die Ausgangsleistung oder die Ausgangsenergie oder auf Energie und Leistung. Hierdurch wird das Signa Rauschverhält- nis deutlich verbessert.The device for optical distance measurement outlined in FIG. 1 is composed of a transmitter 11 and a receiver 13, to which a device for signal evaluation 14 is assigned. A pulse or CW laser, the emitted beam 12 of which is reflected by a target or obstacle, etc., is preferably used as the transmitter 11 and is received by the receiver as a detected signal 12a and fed to the unit for signal evaluation 14. This is assigned a device for signal evaluation 15, a measured variable display device 17 and a signal unit 18. The former 15 carries out an evaluation with respect to distance, amplitude and eye safety, either individually or as a whole, and forwards the evaluation result as a signal to an energy control unit 16, which accordingly regulates the transmission beam 12 of the transmitter 11. This means that the output power and / or the output energy of the transmitter laser is regulated to a minimum by the energy control unit 16 in accordance with the distance of a target detected by the receiving unit 13 through the reflected beam 12a, because good visibility conditions etc. reduce the laser output power or the laser output energy. This significantly improves eye safety. If the visibility is poor or the visibility deteriorates, for example through the onset of rain, smoke or rising fog, this is determined by the unit for signal evaluation 14 in connection with the device for signal evaluation 15 and forwards the correspondingly evaluated received signal 12a to the energy control 16, which now raises the laser transmission beam 12 to a corresponding maximum regulates. This maximum relates in each case to the output power or the output energy or to energy and power. This significantly improves the Signa noise ratio.
Beide Fälle sind durch die Diagramme in den Fig. 2a und 2b angedeutet.Both cases are indicated by the diagrams in FIGS. 2a and 2b.
Nun ist noch vorgesehen, daß das vorgeschlagene Abstandsmeßgerät 10 so konzipiert wird, daß dessen Sendeeinheit 11 bei Detektierung einer Unterschreitung eines vorgegebenen Mindestabstandes automatisch abge¬ schaltet wird und daß die Signalauswertung 14 außerdem bei Unterschrei¬ tung von vorgegebenen Mindestmeßbedingungen und/oder Erkennung einer zu einer Fehlinterpretation führenden Meßbedingung die Signaleinheit 18 ansteuert, durch die ein optisches oder aktustisches Warnsignal gegeben wird. Das optische Warnsignal kann gegebenenfalls auch durch die Me߬ größen-Anzeigeeinrichtung 17 erfolgen. Es ist aber auch vorgesehen, daß die Signaleinheit 18 zusätzlich eine Schaltfunktion übernimmt, bei¬ spielsweise das Abblendlicht oder die Nebelleuchten oder die Scheibenwi¬ scher aktiviert.
It is now also provided that the proposed distance measuring device 10 is designed such that its transmitter unit 11 is automatically switched off when a shortfall in a predetermined minimum distance is detected and that the signal evaluation 14 is also undercut when the predetermined minimum measuring conditions are undershot and / or one of them is detected Misinterpretation leading measurement condition controls the signal unit 18, through which an optical or acoustic warning signal is given. The optical warning signal can optionally also be given by the measurement variable display device 17. However, it is also provided that the signal unit 18 additionally performs a switching function, for example activating the low beam or the fog lights or the windshield wipers.
Claims
1. Einrichtung zur optischen Abstandsmessung mittels eines Me߬ gerätes, das nach dem Puls-Laufzeit- oder Dauerstrich-Verfahren arbeitet und aus einer Sendeeinheit und einer Empfangseinheit besteht, dadurch gekennzeichnet, daß das von der Sendeeinheit (11) ausgesendete Signal (12) entsprechend der von der Empfangseinheit (13) - anhand des rückge¬ streuten und detektierten Signals (12a) - ermittelten Meßbedingung autoadaptiv von einer Einheit zur Signalauswertung (14) mit einer Einrichtung zur Signalbewertung (15) und einer Energiesteuereinheit (16) geregelt wird.1. Device for optical distance measurement by means of a measuring device which operates according to the pulse transit time or continuous wave method and consists of a transmitter unit and a receiver unit, characterized in that the signal (12) emitted by the transmitter unit (11) accordingly the measurement condition determined by the receiving unit (13) - based on the backscattered and detected signal (12a) - is regulated auto-adaptively by a unit for signal evaluation (14) with a device for signal evaluation (15) and an energy control unit (16).
2. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß die Ausgangsleistung und/oder Ausgangsenergie der Sendeeinheit (11) ent¬ sprechend dem von der Empfangseinheit (13) detektierten Abstand eines Zieles oder Hindernisses auf ein Minimum durch die Energiesteuereinheit (16) geregelt wird.2. Device according to claim 1, characterized in that the output power and / or output energy of the transmitter unit (11) accordingly the distance from a target or obstacle detected by the receiver unit (13) is regulated to a minimum by the energy control unit (16).
3. Einrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Sendeeinheit (11) bei Detektierung einer Unterschreitung eines vorgegebenen Mindestabstandes abgeschaltet wird.3. Device according to claim 1 or 2, characterized in that the transmitting unit (11) is switched off upon detection of falling below a predetermined minimum distance.
4. Einrichtung nach den Ansprüchen 1 bis 3, dadurch gekenn¬ zeichnet, daß die Ausgangsleistung und/oder die Ausgangsenergie bei schlechten Sichtverhältnissen, beispielsweise Dunst, Rauch, Nebel etc., von der Energiesteuereinheit (16) auf ein Maximum geregelt wird. 4. Device according to claims 1 to 3, characterized gekenn¬ characterized in that the output power and / or the output energy in poor visibility conditions, such as haze, smoke, fog, etc., is controlled by the energy control unit (16) to a maximum.
5. Einrichtung nach Anspruch 4, dadurch gekennzeichnet, daß die Signalauswertung (14) bei Unterschreitung von vorgegebenen Mindestmeß- bedingungen und/oder Erkennung einer zu einer Fehlinterpretation führen¬ den Meßbedingung die Signaleinheit (18) ansteuert, die ein optisches oder akustisches Warnsignal abgibt und/oder eine Schaltfunktion, z.B. Lichteinschaltung, Scheibenwischerbetätigung etc., aktiviert.5. Device according to claim 4, characterized in that the signal evaluation (14) controls the signal unit (18), which emits an optical or acoustic warning signal when the specified minimum measurement conditions are undershot and / or a measurement condition leading to a misinterpretation is detected / or a switching function, e.g. Lights switched on, wiper actuation etc. activated.
6. Einrichtung nach den Ansprüchen 1 bis 5, dadurch gekenn¬ zeichnet, daß der Abstandsmeßeinrichtung (10) eine Meßgrößen-Anzeige¬ einrichtung (17) zugeordnet ist, die ihre Signale von der Signalaus¬ wertung (14) erhält. 6. Device according to claims 1 to 5, characterized gekenn¬ characterized in that the distance measuring device (10) is assigned a measurand display device (17) which receives its signals from the signal evaluation (14).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3804002 | 1988-02-10 | ||
DEP3804002.6 | 1988-02-10 |
Publications (1)
Publication Number | Publication Date |
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WO1989007771A1 true WO1989007771A1 (en) | 1989-08-24 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/EP1988/001161 WO1989007771A1 (en) | 1988-02-10 | 1988-12-15 | Optical tracking instrument |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0637758A1 (en) * | 1993-08-03 | 1995-02-08 | Yamatake-Honeywell Co. Ltd. | Photoelectric distance sensor |
WO2002042792A1 (en) * | 2000-11-21 | 2002-05-30 | Airborne Hydrography Ab | System and method for measuring water depth |
EP1936400A1 (en) * | 2006-12-20 | 2008-06-25 | Sick Ag | Laser scanner |
EP2781981A3 (en) * | 2013-03-21 | 2017-11-01 | LG Electronics, Inc. | Robot cleaner and method of operating the same |
WO2020032996A2 (en) | 2018-01-10 | 2020-02-13 | Velodyne Lidar, Inc. | Lidar based distance measurements with tiered power control |
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US3898007A (en) * | 1971-11-25 | 1975-08-05 | Aga Ab | Device for electro-optical distance measurement |
GB2019156A (en) * | 1978-04-07 | 1979-10-24 | Agfa Gevaert Ag | Camera focussing system |
EP0066889A2 (en) * | 1981-06-09 | 1982-12-15 | MITEC Mikroelektronik Mikrotechnik Informatik GmbH | Dynamic range control device for a distance measuring equipment |
EP0165403A2 (en) * | 1981-02-03 | 1985-12-27 | MITEC Mikroelektronik Mikrotechnik Informatik GmbH | Method for controlling the dynamics of a distance-measuring apparatus according to the principles of measurement of the transition time of light pulses, and apparatus for carrying out the method |
US4623237A (en) * | 1984-07-07 | 1986-11-18 | Canon Kabushiki Kaisha | Automatic focusing device |
US4699507A (en) * | 1984-03-27 | 1987-10-13 | Nissan Motor Company, Limited | Apparatus and method for measuring the distance to an object |
-
1988
- 1988-12-15 WO PCT/EP1988/001161 patent/WO1989007771A1/en unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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US3898007A (en) * | 1971-11-25 | 1975-08-05 | Aga Ab | Device for electro-optical distance measurement |
GB2019156A (en) * | 1978-04-07 | 1979-10-24 | Agfa Gevaert Ag | Camera focussing system |
EP0165403A2 (en) * | 1981-02-03 | 1985-12-27 | MITEC Mikroelektronik Mikrotechnik Informatik GmbH | Method for controlling the dynamics of a distance-measuring apparatus according to the principles of measurement of the transition time of light pulses, and apparatus for carrying out the method |
EP0066889A2 (en) * | 1981-06-09 | 1982-12-15 | MITEC Mikroelektronik Mikrotechnik Informatik GmbH | Dynamic range control device for a distance measuring equipment |
US4699507A (en) * | 1984-03-27 | 1987-10-13 | Nissan Motor Company, Limited | Apparatus and method for measuring the distance to an object |
US4623237A (en) * | 1984-07-07 | 1986-11-18 | Canon Kabushiki Kaisha | Automatic focusing device |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0637758A1 (en) * | 1993-08-03 | 1995-02-08 | Yamatake-Honeywell Co. Ltd. | Photoelectric distance sensor |
WO2002042792A1 (en) * | 2000-11-21 | 2002-05-30 | Airborne Hydrography Ab | System and method for measuring water depth |
EP1936400A1 (en) * | 2006-12-20 | 2008-06-25 | Sick Ag | Laser scanner |
US7589826B2 (en) | 2006-12-20 | 2009-09-15 | Sick Ag | Laser scanner |
EP2781981A3 (en) * | 2013-03-21 | 2017-11-01 | LG Electronics, Inc. | Robot cleaner and method of operating the same |
WO2020032996A2 (en) | 2018-01-10 | 2020-02-13 | Velodyne Lidar, Inc. | Lidar based distance measurements with tiered power control |
EP3717933A4 (en) * | 2018-01-10 | 2021-08-18 | Velodyne Lidar USA, Inc. | Lidar based distance measurements with tiered power control |
US11415681B2 (en) | 2018-01-10 | 2022-08-16 | Velodyne Lidar Usa, Inc. | LIDAR based distance measurements with tiered power control |
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