A surveying instrument comprising a distance meter, wherein the distance meter is configured for projecting a perceptibility beam onto an object and measuring a distance to the object, wherein the distance meter is configured for running a perceptibility enhancing mode, wherein, when running the perceptibility enhancing mode, the distance meter is directed to emit the perceptibility beam with a modulation, wherein the modulation has a switching frequency of at least 0.25 Hz but lower than 200 Hz.

A surveying instrument comprising a distance meter, wherein the distance meter is configured for projecting a perceptibility beam onto an object and measuring a distance to the object, wherein the distance meter is configured for running a perceptibility enhancing mode, wherein, when running the perceptibility enhancing mode, the distance meter is directed to emit the perceptibility beam with a modulation, wherein the modulation has a switching frequency of at least 0.25 Hz but lower than 200 Hz.

A method is provided for generating or updating a virtual 3D model of a structure or environment using a modelling system. The modelling system includes at least one imaging system, at least one processor and data storage. The method involves transferring a part but not all of a model of a structure or environment from an external data store to the data storage of the modelling system; using the at least one imaging system to collect at least one image of the structure or environment; determining or collecting depth information for the structure or environment; and updating the part of the model in the data storage with the at least one image and the depth information to form an updated part of the model. Also described: corresponding modelling system, processing system, computer program product and drone system.

A surveying instrument for executing a relocation functionality, which determines first coordinates of a stationary target point associated with the start signal, in response to a start signal, a first actuator and a second actuator are controlled such that the stationary target point remains within a detection area of a tracking unit of the surveying instrument, determines second coordinates of the stationary target point, receives an end signal, wherein the second coordinates of the stationary target point are associated with the end signal, and based at least in part on the first and second coordinates of the stationary target point, and determines a relative pose of the surveying instrument with respect to a first setup location and a second setup location, wherein the first setup location is associated with the first coordinates and the second setup location is associated with the second coordinates.

The present invention relates to a tracker and a surveying apparatus comprising the tracker, which improve the reliability of tracking a target. The tracker comprises a an image sensor arrangement having an imaging region composed of a plurality of pixels arranged in a matrix of columns and rows. The imaging region is arranged to take an image of a scene including the target. A controller receives or generates a timing signal indicating a time duration during which an illumination unit is switched on and off, controls the imaging region to take an image of the scene when the illumination unit is switched on, and reads out a subgroup of neighboring columns or rows constituting a stripe window of the imaging region so that an image section including the target is obtained, controls the imaging region to take another image of the scene when the illumination unit is switched off, and reads out another subgroup of neighboring columns or rows constituting another stripe window of the imaging region so that another image section including the target is obtained, and calculates a difference image section by determining a difference between the pixel values of the pixels of the image section and the other image section.

A crack measuring apparatus includes distance-measuring units, an image pickup unit having pixels the positions of which are identified on an imaging device, an infrared image pickup unit having pixels the positions of which are identified on an imaging device and having sensitivity to infrared rays, driving units, angle-measuring units, and an arithmetic control unit, the arithmetic control unit searches for a cracked portion from a temperature difference in an infrared image by turning the infrared image pickup unit, captures an image of the cracked portion by the image pickup unit and identifies a position of the cracked portion from a density difference in the captured image, measures the position of the cracked portion by the distance-measuring units and the angle-measuring units, and acquires three-dimensional absolute coordinates of the cracked portion.

A method for image-based point measurement includes moving a surveying system along a path through a surrounding and capturing a series of images of the surrounding. A subset of images are defined as frames and a subset of frames are defined as key-frames. Textures are identified in first and second frames and are tracked in successive frames to generate first and second frame feature lists. A structure from motion algorithm is used to calculate camera poses for the images based on the first and second frame feature lists. Corresponding image points in images of the series of images are identified using feature recognition in at least a plurality of images. Three-dimensional coordinates of the selected image point are determined using forward intersection with the poses of the subset of images in which corresponding image points are identified. The three-dimensional coordinates of the selected image point are presented to the user.

A method for image-based point measurement includes moving a surveying system along a path through a surrounding and capturing a series of images of the surrounding. A subset of images are defined as frames and a subset of frames are defined as key-frames. Textures are identified in first and second frames and are tracked in successive frames to generate first and second frame feature lists. A structure from motion algorithm is used to calculate camera poses for the images based on the first and second frame feature lists. Corresponding image points in images of the series of images are identified using feature recognition in at least a plurality of images. Three-dimensional coordinates of the selected image point are determined using forward intersection with the poses of the subset of images in which corresponding image points are identified. The three-dimensional coordinates of the selected image point are presented to the user.

A target reflector search device. This device comprises an emitting unit for emitting an emission fan, a motorized device for moving the emission fan over a spatial region, and a receiving unit for reflected portions of the emission fan within a fan-shaped acquisition region, and a locating unit for determining a location of the reflection. An optoelectronic detector of the receiving unit is formed as a position-resolving optoelectronic detector having a linear arrangement of a plurality of pixels, each formed as an SPAD array, and the receiving unit comprises an optical system having an imaging fixed-focus optical unit, wherein the optical system and the optoelectronic detector are arranged and configured in such a way that portions of the optical radiation reflected from a point in the acquisition region are expanded on the sensitivity surface of the optoelectronic detector in such a way that blurry imaging takes place.

A target reflector search device. This device comprises an emitting unit for emitting an emission fan, a motorized device for moving the emission fan over a spatial region, and a receiving unit for reflected portions of the emission fan within a fan-shaped acquisition region, and a locating unit for determining a location of the reflection. An optoelectronic detector of the receiving unit is formed as a position-resolving optoelectronic detector having a linear arrangement of a plurality of pixels, each formed as an SPAD array, and the receiving unit comprises an optical system having an imaging fixed-focus optical unit, wherein the optical system and the optoelectronic detector are arranged and configured in such a way that portions of the optical radiation reflected from a point in the acquisition region are expanded on the sensitivity surface of the optoelectronic detector in such a way that blurry imaging takes place.