Method and system for acquiring 3D surface data of an object to be measured

Abstract

Handheld sensor device for capturing 3D surface data of an object to be measured, wherein the sensor device has first means to determine the position and orientation of the sensor device in space relative to a referencing device, characterized in that the first means have at least three ultrasonic emitters.

Description

[0001] The present invention relates to the field of 3-dimensional (3D) scanning technology, particularly for audiology. More specifically, the present invention relates to the creation of a 3D model of the structure of the entire ear, consisting of the eardrum, ear canal, and auricle ("digital impression"), or the data acquisition for this purpose.

[0002] An important task of a hearing aid acoustician is to create a custom earmold, also known as an earpiece, for hearing aids. The earmold is the part of the hearing aid that, in the case of in-the-ear (ITE) hearing aids, rests directly in the ear. In the case of behind-the-ear (BTE) hearing aids, it rests behind the ear. The optimal fit of the earmold not only improves wearing comfort but also enhances the performance of the hearing aid.

[0003] Currently produced by the applicant, 3D table-top scanners for audiology capture the 3D structure of the outer ear, extending to the beginning of the ear canal, using an indirect method. The 3D structure of the ear is captured from the patient using a negative silicone impression. For this purpose, a two-component silicone compound is placed in the patient's ear. This compound hardens over a specific period and is then removed from the ear. This hardened compound serves as a negative impression of the ear, which can then be captured by a 3D table-top scanner. The resulting data can then be used to create the custom earmold.

[0004] A scanner capable of optically measuring at least the external structure of the ear is known in the prior art. This allows for the direct capture of the ear's 3D structure without an intermediate process involving physical impression taking. Printed evidence for this can be found in US 2016 / 0051134 A1. However, this scanner has several disadvantages. Firstly, it is cumbersome to use because the handheld scanning device is heavy and unwieldy, especially since it integrates many components, such as a screen. Secondly, only the outer part of the ear can be measured, as the scanning device cannot penetrate deep into the ear canal. Complete measurement of the ear canal is particularly important for state-of-the-art hearing aids that sit close to or on the user's eardrum.Furthermore, combining the individual images to obtain complete information about the 3D structure of the inner ear is extremely complicated with this scanner, as each individual image only captures a ring-shaped contour line. Additionally, fixed optical markers outside the ear must always be included in the individual images for merging them, which severely limits the ability to capture the inner ear or ear canal.

[0005] Regarding the state of the art, reference is also made to US 2015 / 0057533 A1, from which an optical scanning device is known.

[0006] From DE 203 06 638 U1 a device for the preoperative planning of soft tissue operations is known.

[0007] US patent 2014 / 0200408 A1 describes an otoscanner with fan and ring laser.

[0008] From EP 2 026 034 A2 a device for determining the 3D coordinates of an object, in particular a tooth, is known.

[0009] Furthermore, an image processing system, display system, image processing method and image processing program is known from JP 2020-151008 A.

[0010] The invention is therefore based on the objective of avoiding the disadvantages of the prior art and in particular of further developing a system for acquiring 3D surface data of an object to be measured, especially the inside of an ear, or its components (sensor device and / or referencing device) or a corresponding method in such a way that individual recordings can be combined more easily, quickly and reliably in order to create the most accurate and comprehensive 3D model of the object possible.

[0011] This problem is solved by a system according to claim 22, a handheld sensor device according to claim 1, and a referencing device according to claim 12. Furthermore, this problem is solved by a method for acquiring 3D surface data of an object to be measured according to claim 30 and a corresponding device according to claim 35.

[0012] The invention relates in particular to a handheld sensor device for acquiring 3D surface data of an object to be measured, wherein the sensor device comprises first means for determining the position and orientation of the sensor device in space relative to a referencing device, wherein the first means comprise at least three ultrasonic emitters. By acquiring the position and orientation of the sensor device in space relative to a referencing device, a further source of information is available, particularly when the object is imaged by the sensor device, for creating a 3D model of the object by combining the individual images. The position and orientation of the sensor device can be determined by ultrasonic time-of-flight measurement using ultrasonic receivers integrated into a referencing device.The ultrasonic time-of-flight measurements serve to roughly determine the three-dimensional spatial position of the sensor device, i.e., in particular an optical stereo sensor, in relation to the object to be measured via a referencing device attached to the object.

[0013] For ease of use, the sensor device has a base in the form of a tube. This tube preferably has a diameter of a few millimeters, so that it can be easily inserted into an ear canal.

[0014] Preferably, the sensor device has at least three struts that project substantially perpendicularly from one end of the base body. It is preferred that the at least three struts are arranged substantially in one plane and preferably each at an angle of approximately 90 degrees or approximately 120 degrees to one another. Preferably, the at least three ultrasonic emitters are arranged at the respective ends of the at least three struts facing away from the base body. The spacing and offset of the ultrasonic emitters allow for optimal detection of the position and orientation of the sensor device.

[0015] Furthermore, it is preferred that the arrangement of the at least three webs is such that a first and a second of the at least three webs together with the base body form a plane and a third web together with the base body forms a plane perpendicular to it.

[0016] According to a preferred embodiment of the invention, the base body of the sensor device includes one or more of the following: image acquisition means, projection means for projecting a structured pattern onto the object, and / or illumination means for the object. Preferably, the image acquisition means are provided for optically capturing the 3D surface data of the object and preferably comprise at least two cameras with overlapping capture areas. In this way, stereoscopic images can be produced, i.e., images containing information about the 3D surface structure of the object to be measured.

[0017] Furthermore, it is preferred that the determination of the sensor's position in space relative to the referencing device is used to control a cursor on a screen. Advantageously, the sensor has a control element, preferably a capacitively sensitive surface element. The sensor can then be moved in space to move a cursor on a screen. The control element can then be used, for example, to click a button over which the cursor is located and make a selection. In this embodiment, the sensor element gains additional "mouse functionality."

[0018] Furthermore, it is preferred that the sensor device includes at least one tactile sensor, preferably the tactile sensor being used to detect contact with the object. Such contact is generally undesirable, so detecting contact can help prevent it. However, detecting contact also provides further information about the 3D properties of the object, since the position and orientation of the sensor device are known at the time of contact.

[0019] The invention relates in particular to a referencing device cooperating with a sensor device for acquiring 3D surface data of an object to be measured, wherein the referencing device has second means for determining the position and orientation of a sensor device in space relative to the referencing device. The first and second means work together to determine the position and orientation of a sensor device in space relative to the referencing device by means of ultrasonic time-of-flight measurement. The referencing device is attached to the object to be measured, and the determination of the position and orientation of a sensor device in space relative to the referencing device thus also determines the position and orientation of a sensor device in space relative to the object to be measured.

[0020] According to the invention, the second means have at least three ultrasound receivers and preferably, to increase the measurement accuracy of the ultrasound transit-time measurement, a plurality of ultrasound receivers. These are preferably arranged in a ring shape.

[0021] According to a metrologically preferred embodiment of the invention, the referencing device further comprises calibration means for calibrating the determination of the position and orientation of the sensor device. Preferably, the sensor device is an optical sensor, and the calibration means have at least one optical marker. The ultrasonic time-of-flight measurement is therefore calibrated by means of a simultaneous optical measurement. Such calibration is particularly advantageous because the time of flight of ultrasonic signals depends on the temperature and humidity of the air in which they propagate.The invention preferably uses the optical imaging means already intended for measuring the ear to detect optical markers at known positions, while the position and orientation of the sensor device are determined by ultrasound, so that the ultrasound time-of-flight measurements can be initially calibrated. In contrast to the prior art, the optical markers are not recorded together with the images of the object and are only recorded before the start of the actual measurement, i.e., separately in time (beforehand) and space (further away from the ear).

[0022] In a structurally preferred embodiment of the invention, the referencing device is designed as a holding device that can be attached to the object. Preferably, the referencing device is designed as a user-worn headpiece. Advantageously, the headpiece has a ring at one end, which is preferably arranged in the intended position around the object, which is preferably the user's ear. For improved attachment, the headpiece preferably has a counter-support at the end opposite one end. Preferably, the second means and the calibration means are formed on the ring. Furthermore, the referencing device has a screen. Advantageously, the screen is arranged above the ring and on the same side of the headpiece as the ring. The user's head is used to hold components, in particular the screen.In contrast to the state of the art, a particular advantage here is that the screen is no longer built into the handheld sensor device, allowing it to be designed to be lightweight and easy to handle.

[0023] The invention relates in particular to a system for acquiring 3D surface data of an object to be measured, wherein the system comprises a handheld sensor device and a referencing device, wherein the sensor device has first means for determining the position and orientation of the sensor device in space relative to the referencing device, and wherein the referencing device has second means for determining the position and orientation of the sensor device in space relative to the referencing device. The first and second means work together to determine the position and orientation of the sensor device in space relative to the referencing device. Preferably, the first and second means are ultrasonic emitters and receivers, and the 3D spatial orientation (position and orientation) of the sensor device is determined by ultrasonic time-of-flight measurements.

[0024] The means for transmitting images, the means for controlling a cursor, the means for operating a cursor, the means for capturing images of the object, the means which control the at least three ultrasonic emitters for the emission of ultrasonic signals and determine the position and orientation of the sensor device in space relative to the referencing device from the transit times of the ultrasonic signals determined by means of the plurality of ultrasonic receivers, and the means for assembling the images are preferably provided outside the sensor device and the referencing device, and advantageously in an external control unit and / or a PC.

[0025] Preferably, the following step is carried out before starting the process according to the invention: - Calibrating the detection of the position and orientation of the sensor device in space relative to the referencing device by stopping the sensor device at at least one predetermined location of the referencing device and detecting with the image detection means of the sensor device at least one optical marker which is arranged at the at least one predetermined location of the referencing device, while simultaneously detecting the position and orientation of the sensor device in space relative to the referencing device.

[0026] Preferably, the position and orientation of the sensor device in the room is determined by means of ultrasonic time-of-flight measurement.

[0027] Furthermore, it is preferred that in step (a) each recording of the object with the image acquisition means of the sensor device has two images which were taken by two cameras with overlapping detection range.

[0028] Preferably, a structured pattern is projected onto the object during the image acquisition process.

[0029] Further preferred embodiments of the invention are disclosed in the dependent claims.

[0030] The invention, as well as further features, objectives, advantages and possible applications thereof, will be explained in more detail below with reference to a description of preferred embodiments and the accompanying drawings. In the drawings, the same reference numerals denote the same or corresponding elements.

[0031] All features described and / or illustrated, whether individually or in any meaningful combination, constitute the subject matter of the present invention, irrespective of their compilation in the claims or their cross-references. The drawings show: Fig. 1 a schematic view of a preferred embodiment of the present invention, which shows an in-ear scanner system with in particular a handheld sensor device and a referencing device; Fig. 2 a schematic perspective view from the front of the handheld sensor device according to Fig. 1; Fig. 3 a schematic cross-sectional view of the referencing device according to Fig. 1; and Fig. 4 a schematic block diagram of the in-ear scanner system according to Fig. 1.

[0032] With reference to the accompanying drawings, a preferred embodiment of the present invention in the form of an audiology or (in-)ear scanner, which can directly capture the 3D structure of a patient's ear 11 without having to take a physical impression of the 3D structure of the ear 11 within the process chain, is explained in more detail below. This ear scanner comprises, in particular, two components, hereinafter referred to as the handheld sensor device or handpiece 20 and the referencing device 8. The referencing device 8 has a fixed reference position relative to the patient's ear 11 and serves to determine the position of the handpiece 20 relative to the ear 11. For this purpose, the handpiece 20 has three or more signal generators 21, 22, 23. The referencing device 8 has three or more receiver units, preferably six receiver units 10, 12, 14, 16, 18, 19.The receiving units 10, 12, 14, 16, 18, 19 of the referencing device 8 receive the signals emanating from the signal generators 21, 22, 23 of the handpiece 20 over time, relative to a common time base of signal generation. The time-of-flight measurement of the signal paths of the respective combinations of signal generators and receiving units allows for an unambiguous determination of the position of the handpiece 8 relative to the referencing device 8 and thus to the ear 11. For the calibration of the position determination, the referencing device 8 has one or more fixed and unambiguous reference points 9, 13, 17 against which the handpiece 20 can be held. By measuring the time-of-flight of the signal paths of the respective combinations of signal generators and receiving units of the handpiece 20 when held against the fixed, unambiguous positions of these reference points 9, 13, 17, the position determination of the handpiece 20 can be calibrated.The handpiece 20 itself has a measuring tip 3, which can be held against the auricle 11 or inserted into the ear canal 15 up to the eardrum. The measuring tip 3 has two or more cameras 2, which have an overlapping detection area. To orient the measuring tip 3 inserted into the ear 11, a screen 27 is attached to the referencing device 8, which displays a live image of the overlapping detection area of ​​the cameras 2 on the measuring tip 3. One or more light sources, e.g., in the form of an optical fiber 5, on the measuring tip 3 result in homogeneous illumination of the overlapping detection area. This enables stereoscopic detection and thus measurement of the 3D properties of the surface located within the detection area.Here, individual surface points are assigned as unique features within the respective detection areas of the cameras 2, and the distance to the measuring tip 3 is determined via triangulation. To increase the feature density on featureless surfaces, the measuring tip 3 is equipped with one or more additional light sources that provide structured illumination. This illuminates a featureless surface, thereby increasing the detectable unique feature density. By moving the measuring tip 3, surface segments adjacent to the respective detection areas can be sequentially captured. The previously described simultaneous position determination of the handpiece 20, and thus of the measuring tip 3, enables the combination of these sequentially captured surface segments into a single 3D model.To capture additional surface points and / or areas outside the overlapping detection ranges of the cameras 2, the measuring tip 3 is additionally equipped with a touch-sensitive sensor 7. When this sensor 7 touches the surface to be scanned and the handpiece 20 is simultaneously positioned, individual surface measurement points can be captured. By moving the measuring tip 3 and the sensor detecting further contact points, adjacent surface points can also be captured sequentially and combined into a single 3D dataset of the surface. The entire system of this audiology scanner is operated in conjunction with the handpiece, the referencing device, and the screen 27 attached to the referencing device. The respective position of the handpiece in space is transferred to a corresponding position of a cursor 28 on the screen 27.Individual menu items displayed on screen 27 (shown here as examples; 29, 30) and / or functions are selected based on the handpiece's position in space. Selection is confirmed via one or more touch-sensitive controls on the handpiece. Switching between navigation mode and initiating a 3D scan is also done via one or more controls. A control unit 32 and a PC 33 are provided for process control, component control, and data acquisition.

[0033] The Fig. 1, Fig. 2, Fig. 3 and Fig. Figure 4 schematically shows an embodiment of the concept of an audiology scanner as the subject of this invention disclosure, which can capture the 3D structure of a patient's ear directly on the patient, using a handpiece 20 with measuring tip 3 and a referencing device 8 with a retaining bracket 26 and a counter-support 31 for determining the position of the handpiece relative to the ear 11 and ear canal 15 to be scanned. The measuring tip 3 (see the schematically enlarged representation of the Fig.1) In this embodiment, the device consists of a metallic guide in the form of a tube 1, which can be held against the auricle of the ear 11 or inserted into the ear canal 15 of the ear 11. Two cameras 2 with overlapping detection areas are embedded at the opening end of this tube 1, enabling stereoscopic recordings for 3D data generation of the ear, including the auricle 11 and ear canal 15. An optical fiber is used to illuminate the overlapping detection area of ​​the two cameras 2, with its exit end 5 pointing towards the overlapping detection area. By coupling light to the other end of the optical fiber, homogeneous illumination of the overlapping detection area of ​​the two cameras 2 is achieved.A microprojection unit 6, consisting of a light emitter, a front-mounted mask with a structured pattern, and imaging optics, generates structured illumination in the overlapping detection area of ​​the two cameras 2. A plane-parallel protective glass 4, positioned in front of these units, protects the cameras 2, the optical fiber 5, and the microprojection unit 6. In addition to these components 2, 4, 5, 6 for optically capturing the 3D structure within the detection area of ​​the two cameras, this measuring tip 3 has a touch-sensitive sensor 7. This can be, for example, a capacitive sensor that can detect touch via capacitive coupling when in contact with the patient in the ear canal 15. This described measuring tip 3 of the handpiece 20 is connected via struts to three orthogonally aligned signal emitters 21, 22, 23.In this embodiment, these can be sequentially pulse-emitting ultrasonic emitters. The pulses emitted by these emitters 21, 22, 23 are detected by a referencing device 8, which is stationary relative to the ear 11 of a head 25 to be detected, mounted on a support bracket 26 with a counter-support 31. In this embodiment, this system consists of six receiving units 10, 12, 14, 16, 18, 19 in the form of ultrasonic receivers, which are connected to each other in a ring configuration. These detect the pulses emitted by the signal emitters 21, 22, 23 over time, relative to a common time base and the signal generation. The time-of-flight measurement from the signal paths of the respective combinations of signal generators 21, 22, 23 and receiving units 10, 12, 14, 16, 18, 19 allows a unique determination of the position of the handpiece 20 relative to the referencing device 8 and thus to the ear 11.For calibrating the position determination, the referencing device 8 in this embodiment has three fixed and unambiguous reference points 9, 13, 17 in the form of modified dot codes (Quick Response Codes, QR Codes), which the cameras 2 can detect in their local 3D orientation relative to the handpiece 20 as they approach. By optically measuring these three reference points 9, 13, 17, with simultaneously measuring the propagation time from the signal paths of the respective combinations of signal generators 21, 22, 23 and receiver units 10, 12, 14, 16, 18, 19, the position determination of the handpiece can be calibrated. The entire system of this audiology scanner is operated in conjunction with handpiece 20, referencing device 8 and the screen 27 attached to the referencing device 8. The respective position of the handpiece 20 in space is transferred to a corresponding position of a cursor 28 on the screen 27.In this embodiment, the referencing device 8 and the screen 27 are mechanically connected to each other via a retaining bracket 26. Individual menu items displayed on the screen 27 (shown here by way of example; 29, 30) can thus be selected based on the respective position of the handpiece in space and the corresponding position of the cursor 28 on the screen 27. In this embodiment, selection confirmation is effected via a single control element on the handpiece 20 in the form of a capacitively sensitive surface 24. This single control element 24 is also used to switch between navigation mode and triggering a 3D scan.

[0034] The embodiment of a novel audiology scanner described as the subject of this invention, which can capture the 3D structure of a patient's ear directly on the patient, is directly adaptable to other fields of application. The creation of 3D data using stereoscopy coupled with a position control system enables not only 3D data acquisition in audiology. The basic concept of the present invention is also applicable to other limited scan volumes. For example, it is conceivable to use the invention in an intraoral scanner in the dental field. A position control system in combination with a scanning handpiece could significantly increase the scanning accuracy compared to conventional intraoral systems. In addition to this field of application, other industrial applications with limited scan volumes are also conceivable.

[0035] The invention has been explained in more detail above with reference to preferred embodiments thereof. However, it is obvious to a person skilled in the art that various variations and modifications can be made without deviating from the underlying concept of the invention. Reference symbol list: 1 tube 2 Image capture devices or cameras 3 measuring tips 4 protective glass 5 Exit end of the fiber optic cable 6 Projection devices or micro-projection units 7 touch-sensitive sensors 8 Referencing device 9, 13, 17 Reference points or markings 10, 12, 14, 16, 18, 19 receiving units 11 Ear (pinna) 15 Ear canal 20 Handpiece or handheld sensor device 21, 22, 23 Ultrasound emitters or signal emitters 24 Control element 25 head 26 retaining brackets 27-inch screen 28 cursors 29, 30 menu items 31 Counter-print 32 Control unit 33 PC

Claims

[1] Handheld sensor device for detecting 3D surface data of an object to be measured, wherein the sensor device has first means for determining the position and orientation of the sensor device in space relative to a referencing device, characterized by that the first means comprise at least three ultrasonic emitters. [2] Sensor device according to claim 1, characterized by that the sensor device has a base body in the form of a tube. [3] Sensor device according to claim 1 or 2, characterized by that the sensor device has at least three webs which protrude substantially perpendicularly from one end of the base body. [4] Sensor device according to claim 3, characterized by that the at least three webs are arranged substantially in one plane and are preferably each arranged at an angle of approximately 90 degrees or approximately 120 degrees to one another. [5] Sensor device according to claim 3 or 4, characterized by that the at least three ultrasonic emitters are arranged at respective ends of the at least three webs facing away from the base body. [6] Sensor device according to one of claims 2 to 5, characterized by that one or more of the following group are provided in the base body: image capture means, projection means for projecting a structured pattern onto the object and / or illumination means for the object. [7] Sensor device according to claim 6, characterized by that the image capture means are provided for optically capturing the 3D surface data of the object and preferably have at least two cameras with an overlapping detection range. [8] Sensor device according to one of the preceding claims, characterized bythat the determination of the position of the sensor device in space relative to the referencing device is used to control a cursor on a screen. [9] Sensor device according to one of the preceding claims, characterized by that the sensor device has an operating element, preferably a capacitively sensitive surface element. [10] Sensor device according to one of the preceding claims, characterized by that the sensor device has at least one tactile sensor. [11] Sensor device according to claim 10, characterized by that the tactile sensor is intended to detect touch of the object. [12] Referencing device for acquiring 3D surface data of an object to be measured, wherein the referencing device has second means for determining the position and orientation of a sensor device in space relative to the referencing device, characterized bythat the second means comprise a plurality of ultrasound receivers. [13] Referencing device according to claim 12, characterized by that the referencing device further comprises calibration means for calibrating the determination of the position and orientation of the sensor device. [14] Referencing device according to claim 12 or 13, characterized by that the sensor device is an optical sensor and the calibration means have at least one optical marking. [15] Referencing device according to one of claims 12 to 14, characterized by that the referencing device is designed as a holding device that can be attached to the object. [16] Referencing device according to claim 15, characterized by that the referencing device is formed on a head of a user of wearable brackets. [17] Referencing device according to claim 16, characterized bythat the bracket has a ring at one end, which is preferably arranged in the intended attachment position around the object, which is preferably the ear of a user. [18] Referencing device according to claim 16 or 17, characterized by that the bracket has a counter-holding support at an end opposite one end. [19] Referencing device according to claim 17 or 18, characterized by that the second means and the calibration means are formed on the ring. [20] Referencing device according to one of claims 12 to 19, characterized by that the referencing device further comprises a screen. [21] Referencing device according to one of claims 17 to 20, characterized by that the screen is positioned above the ring and on the same side of the temple as the ring. [22] System for acquiring 3D surface data of an object to be measured, the system comprising a sensor device according to one of claims 1 to 11 and a referencing device according to one of claims 12 to 21. [23] A system according to claim 22, wherein the system comprises a sensor device according to any one of claims 6 to 11 and a referencing device according to any one of claims 20 or 21, and wherein the system further comprises: - Means for transmitting images captured by the image capturing means of the sensor device for display on the screen of the referencing device. [24] A system according to claim 22 or 23, wherein the system comprises a referencing device according to any one of claims 20 or 21, and wherein the system further comprises: - Means for controlling a cursor on the screen of the referencing device by means of the sensor device through the determined position and orientation of the sensor device in space relative to the referencing device. [25] A system according to any one of claims 22 to 24, wherein the system comprises a sensor device according to any one of claims 9 to 11 and a referencing device according to any one of claims 20 or 21, and wherein the system further comprises: - Means for actuating a cursor on the screen of the referencing device by detecting the actuation of the operating element of the sensor device. [26] A system according to any one of claims 22 to 25, wherein the system further comprises: - Means which control the at least three ultrasonic emitters to emit ultrasonic signals and which determine the position and orientation of the sensor device in space relative to the referencing device from the transit times of the ultrasonic signals determined by means of the plurality of ultrasonic receivers. [27] A system according to any one of claims 22 to 26, wherein the system comprises a sensor device according to any one of claims 6 to 11, and wherein the system further comprises: - Means for capturing images of the object with the image capturing means of the sensor device, wherein the position and orientation of the sensor device in space relative to the referencing device is determined for each image. [28] The system of claim 27, further comprising: - Means of composing the images to create a 3D model of the object. [29] A system according to any one of claims 23 to 28, wherein the system is an in-ear scanner or an intraoral scanner. [30] Method for acquiring 3D surface data of an object to be measured, with a system according to one of claims 22 to 29, wherein the system comprises a sensor device according to one of claims 6 to 11, characterized by following steps: (a) capturing images of the object with the image capturing means of the sensor device, wherein the position and orientation of the sensor device in space relative to the referencing device is determined for each image; and (b) Combining the images to create a 3D model of the object using the position and orientation of the sensor device recorded in step (a). [31] Method according to claim 30, characterized by that the following step is carried out before the procedure begins: - Calibrating the detection of the position and orientation of the sensor device in space relative to the referencing device by stopping the sensor device at at least one predetermined location on the referencing device and detecting with the image detection means of the sensor device at least one optical marking which is arranged at the at least one predetermined location on the referencing device, while simultaneously detecting the position and orientation of the sensor device in space relative to the referencing device. [32] Method according to claim 30 or 31, characterized by that the position and orientation of the sensor device in the room is recorded using ultrasonic transit time measurement. [33] Method according to one of claims 30 to 32, characterized bythat in step (a) each image of the object taken with the image capturing means of the sensor device comprises two images which were taken by two cameras with an overlapping detection range. [34] Method according to claim 33, characterized by that a structured pattern is projected onto the object during the recording of the image capture means. [35] Device comprising a sensor device according to one of claims 1 to 11 and a referencing device according to one of claims 12 to 21 for carrying out the method according to one of claims 30 to 34.

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