ATE554700T1 - Auflösung magnetischer dipolmehrdeutigkeit bei positionsverfolgungsmessungen - Google Patents

Auflösung magnetischer dipolmehrdeutigkeit bei positionsverfolgungsmessungen

Info

Publication number
ATE554700T1
ATE554700T1 AT07250883T AT07250883T ATE554700T1 AT E554700 T1 ATE554700 T1 AT E554700T1 AT 07250883 T AT07250883 T AT 07250883T AT 07250883 T AT07250883 T AT 07250883T AT E554700 T1 ATE554700 T1 AT E554700T1
Authority
AT
Austria
Prior art keywords
magnetic
position tracking
dipol
ambiguity
resolution
Prior art date
Application number
AT07250883T
Other languages
English (en)
Inventor
Assaf Govari
Meir Bar-Tal
Dudi Reznick
Doron Ludwin
Avi Shalgi
Yaron Keidar
Original Assignee
Biosense Webster Inc
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 Biosense Webster Inc filed Critical Biosense Webster Inc
Application granted granted Critical
Publication of ATE554700T1 publication Critical patent/ATE554700T1/de

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
    • G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
    • G01S5/16—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using electromagnetic waves other than radio waves
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/06—Devices, other than using radiation, for detecting or locating foreign bodies ; determining position of probes within or on the body of the patient
    • A61B5/061—Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body
    • A61B5/062—Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body using magnetic field
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B90/00—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
    • A61B90/36—Image-producing devices or illumination devices not otherwise provided for
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B34/00—Computer-aided surgery; Manipulators or robots specially adapted for use in surgery
    • A61B34/20—Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
    • A61B2034/2046—Tracking techniques
    • A61B2034/2051—Electromagnetic tracking systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B90/00—Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
    • A61B90/39—Markers, e.g. radio-opaque or breast lesions markers
    • A61B2090/3954—Markers, e.g. radio-opaque or breast lesions markers magnetic, e.g. NMR or MRI
    • A61B2090/3958—Markers, e.g. radio-opaque or breast lesions markers magnetic, e.g. NMR or MRI emitting a signal
AT07250883T 2006-03-03 2007-03-02 Auflösung magnetischer dipolmehrdeutigkeit bei positionsverfolgungsmessungen ATE554700T1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US11/368,243 US8180430B2 (en) 2005-02-22 2006-03-03 Resolution of magnetic dipole ambiguity in position tracking measurements

Publications (1)

Publication Number Publication Date
ATE554700T1 true ATE554700T1 (de) 2012-05-15

Family

ID=38068773

Family Applications (1)

Application Number Title Priority Date Filing Date
AT07250883T ATE554700T1 (de) 2006-03-03 2007-03-02 Auflösung magnetischer dipolmehrdeutigkeit bei positionsverfolgungsmessungen

Country Status (11)

Country Link
US (2) US20060241397A1 (de)
EP (1) EP1829477B1 (de)
JP (1) JP5265122B2 (de)
KR (1) KR20070090813A (de)
CN (2) CN101803924B (de)
AT (1) ATE554700T1 (de)
AU (1) AU2007200938B2 (de)
BR (1) BRPI0700635A (de)
CA (2) CA2579542C (de)
IL (1) IL181676A (de)
MX (1) MX2007002599A (de)

Families Citing this family (47)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005087128A1 (en) 2004-03-05 2005-09-22 Hansen Medical, Inc. Robotic catheter system
US20060241397A1 (en) * 2005-02-22 2006-10-26 Assaf Govari Reference pad for position sensing
US7324915B2 (en) * 2005-07-14 2008-01-29 Biosense Webster, Inc. Data transmission to a position sensor
EP2005208B1 (de) 2006-03-31 2017-08-16 Koninklijke Philips N.V. System zum lokalen fehlerausgleich in elektromagnetischen verfolgungssystemen
DE102006029122A1 (de) * 2006-06-22 2007-12-27 Amedo Gmbh System zur Bestimmung der Position eines medizinischen Instrumentes
FR2911691B1 (fr) * 2007-01-18 2010-11-26 Bertrand Lombard Transducteur magnetique et procede de calcul associe pour dispositif de localisation spatiale electromagnetique principalement destine a la chirurgie assistee par ordinateur.
ES2651898T3 (es) 2007-11-26 2018-01-30 C.R. Bard Inc. Sistema integrado para la colocación intravascular de un catéter
JP2010187708A (ja) * 2008-01-10 2010-09-02 Univ Of Tokushima 顎運動の測定装置とこれに使用されるセンサコイルの製造方法
US20100305427A1 (en) * 2009-06-01 2010-12-02 General Electric Company Long-range planar sensor array for use in a surgical navigation system
CA2733621C (en) * 2010-03-10 2017-10-10 Northern Digital Inc. Multi-field magnetic tracking
RU2456642C2 (ru) * 2010-08-25 2012-07-20 Закрытое акционерное общество "МЕРА" Способ локализации магнитного диполя
EP2939601B1 (de) 2011-09-06 2018-11-14 eZono AG Magnetische medizinische vorrichtung
GB201303917D0 (en) 2013-03-05 2013-04-17 Ezono Ag System for image guided procedure
US20140257080A1 (en) * 2013-03-05 2014-09-11 Ezono Ag System for ultrasound image guided procedure
US9257220B2 (en) 2013-03-05 2016-02-09 Ezono Ag Magnetization device and method
US9459087B2 (en) 2013-03-05 2016-10-04 Ezono Ag Magnetic position detection system
US9480415B2 (en) 2013-04-26 2016-11-01 Medtronic Navigation, Inc. Electromagnetic coil apparatuses for surgical navigation and corresponding methods
DE102013221026A1 (de) * 2013-10-16 2015-04-16 Fiagon Gmbh Feldgenerator und Lageerfassungssystem
US9241656B2 (en) * 2013-10-25 2016-01-26 Biosense Webster (Israel) Ltd. Serially connected autonomous location pads
DE102013222230A1 (de) 2013-10-31 2015-04-30 Fiagon Gmbh Chirurgisches Instrument
US9474466B2 (en) * 2013-12-23 2016-10-25 Biosense Webster (Israel) Ltd. Low-profile location pad for magnetic-based intra-body probe tracking system
US20150282734A1 (en) 2014-04-08 2015-10-08 Timothy Schweikert Medical device placement system and a method for its use
CN104049236B (zh) * 2014-06-20 2016-12-07 浙江大学 一种基于具有固定磁偶极矩标记磁源的线性定位方法
US20160135712A1 (en) * 2014-11-13 2016-05-19 Angiodynamics, Inc. System and method for determing the position of a catheter
US11096605B2 (en) 2015-03-31 2021-08-24 Medtronic Navigation, Inc. Modular coil assembly
US11109774B2 (en) * 2015-07-06 2021-09-07 Biosense Webster (Israel) Ltd. Flat location pad using nonconcentric coils
US10932861B2 (en) 2016-01-14 2021-03-02 Auris Health, Inc. Electromagnetic tracking surgical system and method of controlling the same
US10932691B2 (en) 2016-01-26 2021-03-02 Auris Health, Inc. Surgical tools having electromagnetic tracking components
US11000207B2 (en) * 2016-01-29 2021-05-11 C. R. Bard, Inc. Multiple coil system for tracking a medical device
US10151606B1 (en) 2016-02-24 2018-12-11 Ommo Technologies, Inc. Tracking position and movement using a magnetic field
US10343537B2 (en) * 2016-03-08 2019-07-09 Witricity Corporation Method and apparatus for positioning a vehicle
US11324554B2 (en) 2016-04-08 2022-05-10 Auris Health, Inc. Floating electromagnetic field generator system and method of controlling the same
WO2018039672A1 (en) * 2016-08-26 2018-03-01 Musc Foundation For Research Development Metal clip detectors and methods of detection
US10980419B2 (en) * 2016-11-07 2021-04-20 Orthodx Inc Systems and methods for monitoring implantable devices for detection of implant failure utilizing wireless in vivo micro sensors
US10244481B2 (en) * 2017-04-05 2019-03-26 Biosense Webster (Israel) Ltd. System and method for switching on wireless tool only when the location frequencies are detected
US11646113B2 (en) * 2017-04-24 2023-05-09 Biosense Webster (Israel) Ltd. Systems and methods for determining magnetic location of wireless tools
US10830572B2 (en) * 2017-10-12 2020-11-10 Google Llc Hemisphere ambiguity correction in electromagnetic position tracking systems
WO2019075544A1 (en) * 2017-10-19 2019-04-25 Ventripoint Diagnostics Ltd POSITIONING DEVICE AND METHOD
US11065064B2 (en) * 2017-11-14 2021-07-20 Biosense Webster (Israel) Ltd. Calibration of a rigid ENT tool
DE102018211185A1 (de) * 2018-07-06 2020-01-09 Neuroloop GmbH Vorrichtung zur transkutanen Lokalisation eines intrakorporal, subkutan verorteten medizinischen Implantats
EP3719749A1 (de) 2019-04-03 2020-10-07 Fiagon AG Medical Technologies Registrierungsverfahren und -einrichtung
CN112401875B (zh) * 2019-08-23 2022-03-18 南京大学 一种基于电荷感应的运动姿态识别装置及方法
US11832883B2 (en) 2020-04-23 2023-12-05 Johnson & Johnson Surgical Vision, Inc. Using real-time images for augmented-reality visualization of an ophthalmology surgical tool
US20210330394A1 (en) 2020-04-23 2021-10-28 Johnson & Johnson Surgical Vision, Inc. Augmented-reality visualization of an ophthalmic surgical tool
CN111796221A (zh) * 2020-07-23 2020-10-20 中国人民解放军海军工程大学 一种消磁站海底三分量磁传感器精确定位方法
US11925349B2 (en) * 2021-02-26 2024-03-12 Cilag Gmbh International Adjustment to transfer parameters to improve available power
EP4201361A1 (de) * 2021-12-27 2023-06-28 MinMaxMedical Elektromagnetisches echtzeit-ortungssystem

Family Cites Families (62)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4742356A (en) * 1985-12-09 1988-05-03 Mcdonnell Douglas Corporation Method and apparatus for determining remote object orientation and position
US5251127A (en) * 1988-02-01 1993-10-05 Faro Medical Technologies Inc. Computer-aided surgery apparatus
US5120908A (en) * 1990-11-01 1992-06-09 Gazelle Graphic Systems Inc. Electromagnetic position transducer
US5211165A (en) 1991-09-03 1993-05-18 General Electric Company Tracking system to follow the position and orientation of a device with radiofrequency field gradients
CA2142338C (en) * 1992-08-14 1999-11-30 John Stuart Bladen Position location system
US5391199A (en) * 1993-07-20 1995-02-21 Biosense, Inc. Apparatus and method for treating cardiac arrhythmias
US5558091A (en) * 1993-10-06 1996-09-24 Biosense, Inc. Magnetic determination of position and orientation
ATE188108T1 (de) 1994-08-19 2000-01-15 Biosense Inc Medizinisches diagnose-, behandlungs- und darstellungssystem
US6695848B2 (en) * 1994-09-02 2004-02-24 Hudson Surgical Design, Inc. Methods for femoral and tibial resection
US6690963B2 (en) * 1995-01-24 2004-02-10 Biosense, Inc. System for determining the location and orientation of an invasive medical instrument
US6246898B1 (en) * 1995-03-28 2001-06-12 Sonometrics Corporation Method for carrying out a medical procedure using a three-dimensional tracking and imaging system
US5729129A (en) * 1995-06-07 1998-03-17 Biosense, Inc. Magnetic location system with feedback adjustment of magnetic field generator
US6351659B1 (en) * 1995-09-28 2002-02-26 Brainlab Med. Computersysteme Gmbh Neuro-navigation system
EP1481635B1 (de) * 1996-02-15 2007-11-07 Biosense Webster, Inc. Bewegliche Empfangs- und Sendespulen für ein Ortsbestimmungssystem
IL125758A (en) * 1996-02-15 2003-07-06 Biosense Inc Medical probes with field transducers
US6453190B1 (en) * 1996-02-15 2002-09-17 Biosense, Inc. Medical probes with field transducers
US6618612B1 (en) 1996-02-15 2003-09-09 Biosense, Inc. Independently positionable transducers for location system
IL125757A (en) * 1996-02-15 2003-09-17 Biosense Inc Medical procedures and apparatus using intrabody probes
JP3327796B2 (ja) * 1996-12-03 2002-09-24 キヤノン株式会社 インクジェット記録装置及びそれによる記録方法
US6122538A (en) * 1997-01-16 2000-09-19 Acuson Corporation Motion--Monitoring method and system for medical devices
CA2278711A1 (en) * 1997-01-28 1998-07-30 William R. Krause Targeting device for relative positioning of a plurality of devices
DE19703556A1 (de) * 1997-01-31 1998-08-06 Philips Patentverwaltung Verfahren und Anordnung zur Positionsbestimmung bei der Röntgenbildgebung
US6314310B1 (en) * 1997-02-14 2001-11-06 Biosense, Inc. X-ray guided surgical location system with extended mapping volume
US6263230B1 (en) * 1997-05-08 2001-07-17 Lucent Medical Systems, Inc. System and method to determine the location and orientation of an indwelling medical device
US5879297A (en) * 1997-05-08 1999-03-09 Lucent Medical Systems, Inc. System and method to determine the location and orientation of an indwelling medical device
US6147480A (en) * 1997-10-23 2000-11-14 Biosense, Inc. Detection of metal disturbance
JP3933278B2 (ja) * 1997-11-04 2007-06-20 株式会社ワコム 位置指示器を検出可能な位置検出方法及び装置
IL122336A0 (en) * 1997-11-27 1998-04-05 Ultra Guide Ltd System and method for guiding the movements of a device to a target particularly for medical applications
US20030163142A1 (en) * 1997-11-27 2003-08-28 Yoav Paltieli System and method for guiding the movements of a device to a target particularly for medical applications
US6348058B1 (en) * 1997-12-12 2002-02-19 Surgical Navigation Technologies, Inc. Image guided spinal surgery guide, system, and method for use thereof
US6239724B1 (en) * 1997-12-30 2001-05-29 Remon Medical Technologies, Ltd. System and method for telemetrically providing intrabody spatial position
ES2253882T3 (es) * 1998-03-30 2006-06-01 Biosense Webster, Inc. Sensor de bobina de tres ejes.
JP4051764B2 (ja) * 1998-05-29 2008-02-27 株式会社島津製作所 手術器具の位置表示装置
US6373240B1 (en) * 1998-10-15 2002-04-16 Biosense, Inc. Metal immune system for tracking spatial coordinates of an object in the presence of a perturbed energy field
US6487516B1 (en) * 1998-10-29 2002-11-26 Netmor Ltd. System for three dimensional positioning and tracking with dynamic range extension
JP4452868B2 (ja) * 1998-11-12 2010-04-21 独立行政法人産業技術総合研究所 磁気式モーションキャプチャ装置における計測方式
AU3206900A (en) * 1998-12-31 2000-07-31 Ball Semiconductor Inc. Position sensing system
WO2000038570A1 (en) * 1998-12-31 2000-07-06 Ball Semiconductor, Inc. Miniature implanted orthopedic sensors
US6493573B1 (en) * 1999-10-28 2002-12-10 Winchester Development Associates Method and system for navigating a catheter probe in the presence of field-influencing objects
AU1240801A (en) * 1999-10-28 2001-05-08 Enterprise Medical Technology, Inc. Coil structures and methods for generating magnetic fields
US6499488B1 (en) * 1999-10-28 2002-12-31 Winchester Development Associates Surgical sensor
US7039453B2 (en) * 2000-02-08 2006-05-02 Tarun Mullick Miniature ingestible capsule
US6549004B1 (en) * 2000-03-14 2003-04-15 The Board Of Trustees Of The Leland Stanford Junior University Distributed magnetic field positioning system using code division multiple access
US7553280B2 (en) * 2000-06-29 2009-06-30 Sensors For Medicine And Science, Inc. Implanted sensor processing system and method
US6484118B1 (en) * 2000-07-20 2002-11-19 Biosense, Inc. Electromagnetic position single axis system
DE20015775U1 (de) * 2000-09-12 2002-01-31 Stryker Trauma Gmbh Knochennagel
US6917827B2 (en) * 2000-11-17 2005-07-12 Ge Medical Systems Global Technology Company, Llc Enhanced graphic features for computer assisted surgery system
US6666579B2 (en) * 2000-12-28 2003-12-23 Ge Medical Systems Global Technology Company, Llc Method and apparatus for obtaining and displaying computed tomography images using a fluoroscopy imaging system
WO2002067800A2 (en) * 2001-02-27 2002-09-06 Smith & Nephew, Inc. Surgical navigation systems and processes for high tibial osteotomy
US6702459B2 (en) * 2001-04-11 2004-03-09 The Uab Research Foundation Mobile radiography system and process
US6927741B2 (en) 2001-11-15 2005-08-09 Merlin Technology, Inc. Locating technique and apparatus using an approximated dipole signal
US7729742B2 (en) * 2001-12-21 2010-06-01 Biosense, Inc. Wireless position sensor
US6774624B2 (en) * 2002-03-27 2004-08-10 Ge Medical Systems Global Technology Company, Llc Magnetic tracking system
US20040068178A1 (en) 2002-09-17 2004-04-08 Assaf Govari High-gradient recursive locating system
US7256695B2 (en) * 2002-09-23 2007-08-14 Microstrain, Inc. Remotely powered and remotely interrogated wireless digital sensor telemetry system
EP1563315A2 (de) * 2002-11-14 2005-08-17 GE Medical Systems Global Technology Company LLC Auswechselbare lokalisierungseinrichtungen zur benutzung in führungssystemen
WO2004091419A2 (en) * 2003-04-08 2004-10-28 Wasielewski Ray C Use of micro-and miniature position sensing devices for use in tka and tha
US7974680B2 (en) * 2003-05-29 2011-07-05 Biosense, Inc. Hysteresis assessment for metal immunity
US20050062469A1 (en) 2003-09-23 2005-03-24 Anderson Peter Traneus System and method for hemisphere disambiguation in electromagnetic tracking systems
US8046050B2 (en) * 2004-03-05 2011-10-25 Biosense Webster, Inc. Position sensing system for orthopedic applications
US20060241397A1 (en) * 2005-02-22 2006-10-26 Assaf Govari Reference pad for position sensing
US7525309B2 (en) * 2005-12-30 2009-04-28 Depuy Products, Inc. Magnetic sensor array

Also Published As

Publication number Publication date
CN101028188A (zh) 2007-09-05
CN101803924A (zh) 2010-08-18
IL181676A (en) 2014-02-27
US20060241394A1 (en) 2006-10-26
EP1829477A2 (de) 2007-09-05
AU2007200938A1 (en) 2007-09-20
MX2007002599A (es) 2008-11-14
CN101028188B (zh) 2010-12-08
AU2007200938B2 (en) 2012-03-15
JP2007236937A (ja) 2007-09-20
KR20070090813A (ko) 2007-09-06
US20060241397A1 (en) 2006-10-26
CA2858896A1 (en) 2007-09-03
CA2858896C (en) 2017-05-09
JP5265122B2 (ja) 2013-08-14
BRPI0700635A (pt) 2007-11-06
EP1829477B1 (de) 2012-04-25
CA2579542C (en) 2014-11-18
EP1829477A3 (de) 2009-07-08
CN101803924B (zh) 2012-04-25
US8180430B2 (en) 2012-05-15
CA2579542A1 (en) 2007-09-03
IL181676A0 (en) 2007-07-04

Similar Documents

Publication Publication Date Title
ATE554700T1 (de) Auflösung magnetischer dipolmehrdeutigkeit bei positionsverfolgungsmessungen
CN108020150B (zh) 使用磁传感器的多维测量以及相关系统、方法和集成电路
BRPI0703121A (pt) rastreamento de posição imune a distorção utilizando extraporlação de freqüência
MY158671A (en) Techniques for positioning a vehicle
ATE514960T1 (de) System zur kollisionserkennung und verfahren zur schätzung der position eines zieles
DE602006007905D1 (de) System zur Positionserfassung mittels quasi-DC Magnetfeldern
CA2582703A1 (en) Image registration using locally-weighted fitting
ATE532610T1 (de) Verfahren und system zur bestimmung der beziehung zwischen einem roboterkoordinatensystem und einem lokalen koordinatensystem, das im arbeitsbereich des roboters positioniert ist
GB201320076D0 (en) Absolute distance meter based on an undersampling method
ATE485556T1 (de) System und verfahren zum operieren in einem virtuellen 3d-raum
GB2477902A (en) Device and method for measuring six degrees of freedom
ATE419508T1 (de) Verfahren zur kalibrierung eines messsystems
EP2495536A3 (de) 360-Grad-Winkelsensor
WO2013023781A3 (de) Messvorrichtung zum messen magnetischer eigenschaften der umgebung der messvorrichtung
ATE518112T1 (de) Einrichtung und verfahren zur nachverfolgung der bewegung eines werkzeuges einer handhabungseinheit
EP1818647A3 (de) Formmesssystem, Formmessverfahren und Formmessprogramm
ATE383567T1 (de) Vorrichtung, sensoranordnung und verfahren zur kapazitiven positionserfassung eines zielobjekts
WO2002018978A3 (en) Multi-axis locator for detection of buried targets
JP2017191110A (ja) 非接触型磁気線形位置センサー
WO2009004856A1 (ja) 電磁界分布測定装置
Chen et al. Stereo vision sensor calibration based on random spatial points given by CMM
FI20116329A (fi) Mittauskohteen mittaus
DE50214661D1 (de) Verfahren zum messen eines objektes mit einem koordinatenmessgerät mit bildverarbeitungssensor
EP2362189A3 (de) Auf magnetischer Triangulation basierter Positionssensor
WO2010094751A3 (en) Mobile projection system for scaling and orientation of surfaces surveyed by an optical measuring system