Patents by Inventor Christian Grasser
Christian Grasser has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11644309Abstract: The present disclosure provides a method for determining a direction to a geodetic target from a geodetic instrument. The method includes emitting an optical pulse from the geodetic target, capturing a first image and a second image of the geodetic target using a camera arranged at the geodetic instrument, obtaining a difference image between the first image and the second image, and determining a direction to the geodetic target from the geodetic instrument based on the position of the optical pulse in the difference image. The method further includes synchronizing the geodetic instrument and the geodetic target for emitting the optical pulse concurrently with the capturing of the first image and nonconcurrently with the capturing of the second image. The present disclosure also provides a geodetic instrument, a geodetic target and a geodetic surveying system.Type: GrantFiled: July 23, 2021Date of Patent: May 9, 2023Assignee: Trimble ABInventors: Johan Carlén, Mikael Nordenfelt, Christian Grässer
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Publication number: 20220011101Abstract: The present disclosure provides a method for determining a direction to a geodetic target from a geodetic instrument. The method includes emitting an optical pulse from the geodetic target, capturing a first image and a second image of the geodetic target using a camera arranged at the geodetic instrument, obtaining a difference image between the first image and the second image, and determining a direction to the geodetic target from the geodetic instrument based on the position of the optical pulse in the difference image. The method further includes synchronizing the geodetic instrument and the geodetic target for emitting the optical pulse concurrently with the capturing of the first image and nonconcurrently with the capturing of the second image. The present disclosure also provides a geodetic instrument, a geodetic target and a geodetic surveying system.Type: ApplicationFiled: July 23, 2021Publication date: January 13, 2022Inventors: Johan Carlén, Mikael Nordenfelt, Christian Grässer
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Patent number: 11092434Abstract: The present disclosure provides a method for determining a direction to a geodetic target from a geodetic instrument. The method includes emitting an optical pulse from the geodetic target, capturing a first image and a second image of the geodetic target using a camera arranged at the geodetic instrument, obtaining a difference image between the first image and the second image, and determining a direction to the geodetic target from the geodetic instrument based on the position of the optical pulse in the difference image. The method further includes synchronizing the geodetic instrument and the geodetic target for emitting the optical pulse concurrently with the capturing of the first image and nonconcurrently with the capturing of the second image. The present disclosure also provides a geodetic instrument, a geodetic target and a geodetic surveying system.Type: GrantFiled: July 8, 2019Date of Patent: August 17, 2021Assignee: Trimble ABInventors: Johan Carlén, Mikael Nordenfelt, Christian Grässer
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Publication number: 20190331486Abstract: The present disclosure provides a method for determining a direction to a geodetic target from a geodetic instrument. The method includes emitting an optical pulse from the geodetic target, capturing a first image and a second image of the geodetic target using a camera arranged at the geodetic instrument, obtaining a difference image between the first image and the second image, and determining a direction to the geodetic target from the geodetic instrument based on the position of the optical pulse in the difference image. The method further includes synchronizing the geodetic instrument and the geodetic target for emitting the optical pulse concurrently with the capturing of the first image and nonconcurrently with the capturing of the second image. The present disclosure also provides a geodetic instrument, a geodetic target and a geodetic surveying system.Type: ApplicationFiled: July 8, 2019Publication date: October 31, 2019Inventors: Johan Carlén, Mikael Nordenfelt, Christian Grässer
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Patent number: 10168153Abstract: Novel solutions for position measurement, including without limitation tools and techniques that can be used for land surveying and in similar applications. One such tool is a greatly enhanced position measurement system that takes the form of a surveying rod with substantial independent functionality, which can be used with or without a total station or similar device.Type: GrantFiled: September 30, 2013Date of Patent: January 1, 2019Assignee: Trimble Inc.Inventors: Christian Grässer, Peter Cornelius Kistler, James Greenberg, Rod Johnson
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Patent number: 9879993Abstract: Novel tools and techniques that can be used to enhance the effectiveness of photogrammetric tools, such as bundle adjustment. One set of techniques can include a photo-observable backsight operation, in which a position of target point can be observed non-photographically, and this observed position can be used to constrain a pixel coordinate location of the same target point in a bundle adjustment operation. Using another technique, a photo-observable check shot operation, the observed position of another target point can be used to verify the validity of a bundle adjustment calculation. Such techniques can be used together or separately.Type: GrantFiled: September 30, 2013Date of Patent: January 30, 2018Assignee: Trimble Inc.Inventors: Chad McFadden, Amit Joshi, Christian Grässer, Troy L. Brown, Shaojun He
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Patent number: 9874458Abstract: The present invention provides a method for calibrating a geodetic instrument, an instrument and a computer program product thereof. In the method and geodetic instrument of the present invention, a value of at least one parameter affecting the measurements made by the instrument is detected and compared with a predetermined threshold. On the basis of the comparison between the detected value and the predetermined threshold, the instrument aims at a reference target and a calibration is performed using the reference target. The present invention is advantageous in that the accuracy and reliability of the measurements performed by the instrument are increased. Further, the present invention is advantageous in that the requirements on mechanical stability are reduced.Type: GrantFiled: February 13, 2015Date of Patent: January 23, 2018Assignee: Trimble ABInventor: Christian Grässer
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Patent number: 9863782Abstract: The present invention provides a method for calibrating a geodetic instrument, an instrument and a computer program product thereof. In the method and geodetic instrument of the present invention, a value of at least one parameter affecting the measurements made by the instrument is detected and compared with a predetermined threshold. On the basis of the comparison between the detected value and the predetermined threshold, the instrument aims at a reference target and a calibration is performed using the reference target. The present invention is advantageous in that the accuracy and reliability of the measurements performed by the instrument are increased. Further, the present invention is advantageous in that the requirements on mechanical stability are reduced.Type: GrantFiled: February 4, 2015Date of Patent: January 9, 2018Assignee: TRIMBLE ABInventor: Christian Grässer
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Patent number: 9482756Abstract: A tracker unit for a measuring instrument such as a total station is disclosed. The tracker unit comprises a first and at least a second optical radiation source arranged at different positions and each of which is noncoaxially arranged with respect to a tracker pointing axis and adapted to emit optical radiation towards the reflective target when activated. The first and the at least a second optical radiation source are arranged at such positions so that the tracker pointing axis and the position of the first optical radiation source define a first plane and the tracker pointing axis and the position of the at least a second optical radiation source define a second plane, such that the first optical radiation source is coaxial with respect to the tracker pointing axis in a plane perpendicular to the first plane and the at least a second optical radiation source is coaxial with respect to the tracker pointing axis in a plane perpendicular to the second plane.Type: GrantFiled: April 29, 2015Date of Patent: November 1, 2016Assignee: TRIMBLE ABInventors: Christian Grässer, Suat Köker
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Patent number: 9189858Abstract: A method is disclosed for determining coordinates of a target in relation to a surveying instrument wherein a first image is captured using a first camera in a first camera position and orientation, a target is selected by identifying at least one object point in the first image, and first image coordinates of the object point in the first image are measured. In at least one embodiment, a second image is captured using a second camera in a second camera position and orientation, the object point identified in the first image is identified in the second image, and second image coordinates of the object point in the second image are measured. Target coordinates of the target in relation to the rotation center of the surveying instrument are then determined based on the first camera position and orientation, the first image coordinates, the second camera position and orientation, the second image coordinates, and first and second camera calibration data.Type: GrantFiled: February 29, 2008Date of Patent: November 17, 2015Assignee: TRIMBLE ABInventors: Set Svanholm, Michael Vogel, Christian Grässer
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Patent number: 9182229Abstract: Novel solutions for position measurement, including without limitation tools and techniques that can be used for land surveying and in similar applications. One such tool is a greatly enhanced position measurement system that takes the form of a surveying rod with substantial independent functionality, which can be used with or without a total station or similar device.Type: GrantFiled: December 21, 2011Date of Patent: November 10, 2015Assignee: Trimble Navigation LimitedInventors: Christian Grässer, Peter Cornelius Kistler, James Greenberg, Rod Johnson, Magnus Westermark
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Patent number: 9160140Abstract: It is disclosed a method for driving a laser diode such as to enable mitigation or elimination of so called spiking effects related to the number of injected carriers in the laser overshooting the equilibrium value at the beginning of the lasing process. In this manner, among other things, the efficiency of a master oscillator power amplifier that may be utilized in range finding applications will be improved. It is further disclosed an optical pulse transmitter comprising such a laser diode.Type: GrantFiled: May 27, 2014Date of Patent: October 13, 2015Assignee: TRIMBLE ABInventors: Yuri P. Gusev, Mikael Hertzman, Evgeny Vanin, Christian Grässer
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Publication number: 20150276402Abstract: Novel solutions for position measurement, including without limitation tools and techniques that can be used for land surveying and in similar applications. One such tool is a greatly enhanced position measurement system that takes the form of a surveying rod with substantial independent functionality, which can be used with or without a total station or similar device.Type: ApplicationFiled: September 30, 2013Publication date: October 1, 2015Inventors: Christian Grässer, Peter Cornelius Kistler, James Greenberg, Rod Johnson
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Publication number: 20150268347Abstract: A tracker unit for a measuring instrument such as a total station is disclosed. The tracker unit comprises a first and at least a second optical radiation source arranged at different positions and each of which is noncoaxially arranged with respect to a tracker pointing axis and adapted to emit optical radiation towards the reflective target when activated. The first and the at least a second optical radiation source are arranged at such positions so that the tracker pointing axis and the position of the first optical radiation source define a first plane and the tracker pointing axis and the position of the at least a second optical radiation source define a second plane, such that the first optical radiation source is coaxial with respect to the tracker pointing axis in a plane perpendicular to the first plane and the at least a second optical radiation source is coaxial with respect to the tracker pointing axis in a plane perpendicular to the second plane.Type: ApplicationFiled: April 29, 2015Publication date: September 24, 2015Inventors: Christian Grässer, Suat Köker
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Publication number: 20150268043Abstract: Novel tools and techniques that can be used to enhance the effectiveness of photogrammetric tools, such as bundle adjustment. One set of techniques can include a photo-observable backsight operation, in which a position of target point can be observed non-photographically, and this observed position can be used to constrain a pixel coordinate location of the same target point in a bundle adjustment operation. Using another technique, a photo-observable check shot operation, the observed position of another target point can be used to verify the validity of a bundle adjustment calculation. Such techniques can be used together or separately.Type: ApplicationFiled: September 30, 2013Publication date: September 24, 2015Inventors: Chad McFadden, Amit Joshi, Christian Grässer, Troy L. Brown, Shaojun He
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Publication number: 20150160039Abstract: The present invention provides a method for calibrating a geodetic instrument, an instrument and a computer program product thereof. In the method and geodetic instrument of the present invention, a value of at least one parameter affecting the measurements made by the instrument is detected and compared with a predetermined threshold. On the basis of the comparison between the detected value and the predetermined threshold, the instrument aims at a reference target and a calibration is performed using the reference target. The present invention is advantageous in that the accuracy and reliability of the measurements performed by the instrument are increased. Further, the present invention is advantageous in that the requirements on mechanical stability are reduced.Type: ApplicationFiled: February 13, 2015Publication date: June 11, 2015Inventor: Christian GRÄSSER
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Publication number: 20150153200Abstract: The present invention provides a method for calibrating a geodetic instrument, an instrument and a computer program product thereof. In the method and geodetic instrument of the present invention, a value of at least one parameter affecting the measurements made by the instrument is detected and compared with a predetermined threshold. On the basis of the comparison between the detected value and the predetermined threshold, the instrument aims at a reference target and a calibration is performed using the reference target. The present invention is advantageous in that the accuracy and reliability of the measurements performed by the instrument are increased. Further, the present invention is advantageous in that the requirements on mechanical stability are reduced.Type: ApplicationFiled: February 4, 2015Publication date: June 4, 2015Inventor: Christian GRÄSSER
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Patent number: 8978440Abstract: The present invention provides a method for calibrating a geodetic instrument, an instrument and a computer program product thereof. In the method and geodetic instrument of the present invention, a value of at least one parameter affecting the measurements made by the instrument is detected and compared with a predetermined threshold. On the basis of the comparison between the detected value and the predetermined threshold, the instrument aims at a reference target and a calibration is performed using the reference target. The present invention is advantageous in that the accuracy and reliability of the measurements performed by the instrument are increased. Further, the present invention is advantageous in that the requirements on mechanical stability are reduced.Type: GrantFiled: February 29, 2008Date of Patent: March 17, 2015Assignee: Trimble ABInventor: Christian Grässer
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Publication number: 20140300952Abstract: It is disclosed a method for driving a laser diode such as to enable mitigation or elimination of so called spiking effects related to the number of injected carriers in the laser overshooting the equilibrium value at the beginning of the lasing process. In this manner, among other things, the efficiency of a master oscillator power amplifier that may be utilized in range finding applications will be improved. It is further disclosed an optical pulse transmitter comprising such a laser diode.Type: ApplicationFiled: May 27, 2014Publication date: October 9, 2014Applicant: TRIMBLE ABInventors: Yuri P. GUSEV, Mikael HERTZMAN, Evgeny VANIN, Christian GRÄSSER
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Patent number: 8743455Abstract: It is disclosed a method for driving a laser diode such as to enable mitigation or elimination of so called spiking effects related to the number of injected carriers in the laser overshooting the equilibrium value at the beginning of the lasing process. In this manner, among other things, the efficiency of a master oscillator power amplifier that may be utilized in range finding applications will be improved. It is further disclosed an optical pulse transmitter comprising such a laser diode.Type: GrantFiled: June 30, 2009Date of Patent: June 3, 2014Assignee: Trimble ABInventors: Yuri Gusev, Mikael Hertzman, Evgeny Vanin, Christian Grässer