Method of optimally positioning a time-of-flight sensor on a ceiling

Abstract

A method of determining a detection area of a ToF sensor mounted on a ceiling of a room, is presented. The ToF sensor is included in a first device, such as a ceiling panel or luminaire, having predefined dimensions. The method includes obtaining the predefined dimensions of the first device in a second device, which is a user's device such as a smartphone or tablet; obtaining a first image of the room including the first device from a camera of the second device; obtaining a second image of the room including a desired detection area from the camera; determining a projection of the ToF sensor on the second image based on the predefined dimensions of the first device; and determining, using the ToF sensor, a height of a reference object such as a toilet (616) on a floor (716) of the room. The ToF sensor may be repositioned for obtaining an improved detection area. To get the projection (700) of the ToF sensor on the floor (716), the processor of the smartphone may construct two lines (740, 742) on the floor in the camera view which is to visualize the detection area as a dashed box (ABCD) overlayed on the second image, e.g., by using an augmented reality mode of the camera. The camera view (730) includes also a front wall (634) and a side wall (636) of the room. The ToF sensor may be used for fall detection, most advantageously for the detection of elderly people falling.

Description

[0001] Method of optimally positioning a Time-of-Flight sensor on a ceiling

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to positioning of a Time-of-Flight (ToF) sensor on a ceiling for optimal Field-of-View (FoV).

[0004] BACKGROUND

[0005] A ToF sensor typically includes a light emitter, e.g., infrared light-emitting diode (LED) based or laser / Vertical-Cavity Surface-Emitting Laser (VCSEL) based, and a light detector. The light emitter may send light / photons which are reflected by objects and persons in its FoV and which reflected light / photons may be detected by the detector. The time difference between emission and reception provides an actual distance between the object or person and the ToF sensor. A three-dimensional (3D) ToF sensor may include an array of detectors, therefore can generate depth images of a space.

[0006] A 3D ToF sensor can detect, typically in real time, objects and / or persons, e.g., in a room. Such ToF sensor has various applications, such as security surveillance, movement detection and / or fall detection. In the latter example, the position and posture of a person in the room may be detected and it may be detected that the person fell and is lying on the floor, allowing help to be send to the person.

[0007] Automated fall detection is an important function in elderly care solutions. Compared with wearable device based fall detection methods, contactless fall detection via remote sensors, such as 3D ToF sensors, has some unique advantages. For example, not needing to wear a device is less burdensome and cannot be forgotten. Furthermore, a 3D ToF sensor may be powered by mains power, while a wearable device is battery powered and needs to be charged, possibly resulting in a dead battery and no protection. Moreover, a 3D ToF sensor can be very accurate.

[0008] When mounted on the ceiling of a room, a 3D ToF sensor may capture in real time the position and posture of a person in the room. If the person falls and lies on the floor, his / her posture being perceived by the sensor is different from when the person stands or sits, thereby allowing fall detection. CN1 13786190A relates to a method and device, electronic equipment for detecting target falling down. Based on the TOF light wave data sent by a TOF sensor, the detection reference data are determined, the dynamic detection information representing the position change of the to-be-detected target is determined through the detection reference data, whether the detected target falls down or not is judged, the accuracy of falling judgment is improved, and the detection accuracy is improved.

[0009] US2020258364A1 relates to detecting human activity using thermal data and time-of-flight (TOF) sensor data. An array-type thermal sensor is used to generate the thermal data and an array-type TOF sensor is used to generate the TOF data. TOF-derived data, such as distance data, velocity data, and / or acceleration data, can be determined from the TOF data. Human activity in a monitored space may be determined by comparing thermal and TOF-derived data acquired for the monitored space to one or more activity profiles corresponding to one or more types of activities desired to be monitored.

[0010] US2019110741A1 disclose a life rhythm measurement system. A distance measuring device measures 3D information (whether a posture corresponds to a standing posture, a sitting posture, or a lying posture, a movement amount, and absence information) of a measurement target person using a TOF sensor. A management device aggregates the 3D information measured by the distance measuring device for each unit time, estimates a life rhythm (a ratio of each posture per unit period, a movement amount, an absence time, a bedtime, a wake time, and a home return time) of the measurement target person from a 3D data for each time, and accumulates the estimated life rhythm in a storage device. The management device provides information on the life rhythm of the measurement target person accumulated in the storage device to a measurement requester.

[0011] When a ToF sensor is incorrectly positioned on a ceiling, the FoV may not optimally cover the room to be surveillanced.

[0012] SUMMARY

[0013] A summary of aspects of certain examples disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects and / or a combination of aspects that may not be set forth. The present disclosure aims to overcome the drawbacks identified in the background section. In particular, the present disclosure aims to provide a method of positioning a ToF sensor on a ceiling for optimal FoV of the ToF sensor.

[0014] According to an aspect of the present disclosure, a method of determining a detection area of a ToF sensor is presented. The ToF sensor may be mounted on a ceiling of a room. The ToF sensor may be included in a first device having predefined dimensions. The method may include obtaining the predefined dimensions of the first device in a second device. The method may further include obtaining a first image of the room comprising the first device using a camera of the second device. The method may further include obtaining a second image of the room comprising a desired detection area using the camera. The method may further include determining a projection of the ToF sensor on the second image based on the predefined dimensions of the first device. The method may further include determining, using the ToF sensor, a height of a reference object on the desired detection area in the room. The method may further include determining a current detection area of the ToF sensor based on the determined height of the reference object and a distance between the ToF sensor and the desired detection area measured by the ToF sensor and detection angle range of the ToF sensor.

[0015] Examples of a desired detection area are a floor of the room or any other base surface of the room.

[0016] The first image and / or the second image may be obtained using an image mode of the camera. The first image and / or the second image may be obtained using a video mode of the camera. The first image and / or the second image may be obtained using an augmented reality mode, wherein graphical objects may be overlay ed on top of the image.

[0017] The first image and the second image may be obtained by a camera at the same time. In other word, the first image and second image could be part of a same big image respectively. The big image incudes both the first device and a desired detection area of the ToF sensor. Alternatively, the first image and the second image could be a same image, which includes both the first device and a desired detection area of the ToF sensor.

[0018] The first device may be a panel that is mountable on or in a ceiling. The first device may include a luminaire.

[0019] The second device may be an end-user’s device. Non-limiting examples of second devices are: a smartphone; a tablet computer; a portable computer; or any other portable end-user’s device. In an embodiment, the obtaining of the predefined dimensions of the first device in the second device may include a manual input of the predefined dimensions on the second device using a user interface of the second device.

[0020] In an embodiment, the obtaining of the predefined dimensions of the first device in the second device may include a manual input of a model or serial number of the first device on the second device using a user interface of the second device, allowing the second device to obtain the predefined dimensions based on the model or serial number.

[0021] In an embodiment, the obtaining of the predefined dimensions of the first device in the second device may include a visual recognition of the first device by the second device using the camera, allowing the second device to obtain the predefined dimensions based on the visual recognition.

[0022] In an embodiment, the first image may be a first camera image from a two- dimensional (2D) camera of the second device. The method may further include determining, using the first camera image and based on the predetermined dimensions of the first device, a first distance between the ToF sensor and a first wall and a second distance between the ToF sensor and a second wall. The first wall may intersect the second wall. The method may further include determining the projection of the ToF sensor on the second image based on the first distance and the second distance.

[0023] In an embodiment, the method may further include determining a repositioning of the ToF sensor for obtaining an improved detection area.

[0024] In an embodiment, the first image may include at least a part of the ceiling including the first device, at least a part of the first wall and at least a part of the second wall.

[0025] In an embodiment, the second image may include at least a part of the desired detection area including the reference object, at least a part of the first wall and at least a part of the second wall.

[0026] In an embodiment, the method may further include displaying the second image on a display of the second device and overlaying the current detection area of the ToF sensor.

[0027] In an embodiment, the method may further include displaying the second image on a display of the second device and overlaying the improved area of the ToF sensor.

[0028] In an embodiment, the method may further include displaying an instruction on a display of the second device for repositioning the first device to obtain the improved detection area. In an embodiment, the method may further include automatically repositioning the ToF sensor by moving the ToF sensor along a rail to obtain the improved detection area.

[0029] In an embodiment, the method may further include displaying a projection of the ToF sensor on a desired detection area on a display of the second device and overlaying the second image.

[0030] In an embodiment, the method may further include displaying the first distance and the second distance on a desired detection area on a display of the second device and overlaying the second image.

[0031] In an embodiment, the first device may be a light fixture including the ToF sensor and a luminaire.

[0032] According to an aspect of the present disclosure, a device including a ToF sensor is presented. The device may have predetermined dimensions. The ToF sensor may be configured to determine a height of a reference object on a desired detection area of a room. The ToF sensor may be configured to transmit the determined height of the reference object to a second device. The ToF sensor may be repositionable based on a determination of an improved detection area of the ToF sensor determined by the second device.

[0033] In an embodiment, the device may be repositionable to reposition the ToF sensor based on the determination of the improved detection area of the ToF sensor determined by the second device.

[0034] In an embodiment, the ToF sensor may be movably connected to the device. The ToF sensor may be repositionable based on the determination of the improved detection area of the ToF sensor determined by the second device.

[0035] In an embodiment, the device may be a light fixture including the ToF sensor and a luminaire.

[0036] According to an aspect of the present disclosure, a computer program is presented including instruction which, when the program is executed by one or more processors, cause the one or more processors to carry out the method having one or more of the above described features.

[0037] According to an aspect of the present disclosure, a computer-readable storage medium is presented including instructions which, when executed by one or more processors, cause the one or more processors to carry out the method having one or more of the above described features. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbol indicate corresponding parts, in which:

[0039] Fig. 1 shows an example ToF sensor and its FoV;

[0040] Fig. 2 shows an example ToF sensor and its detection area on a floor;

[0041] Fig. 3 shows a panel luminaire including a ToF sensor, according to an example embodiment of the present disclosure;

[0042] Figs. 4A-4B show a top view of a room with a panel luminaire installed on a ceiling of the room, according to an example embodiment of the present disclosure;

[0043] Figs. 5A-5B show a camera view of a ceiling including a panel luminaire with ToF sensor, according to an example embodiment of the present disclosure;

[0044] Fig. 6 shows a 3D camera view of a room, pointing at a ceiling and two walls, according to an example embodiment of the present disclosure;

[0045] Figs. 7-8 show a 3D camera view of a room, pointing at a floor and two walls, according to an example embodiment of the present disclosure;

[0046] Figs 9A-9B show two orientations of a panel with ToF sensor, according to an example embodiment of the present disclosure;

[0047] Fig. 9C shows a 3D camera view of a room, pointing at a floor and two walls, according to an example embodiment of the present disclosure;

[0048] Figs. 10A-10D show examples of panels including ToF sensor, according to example embodiments of the present disclosure;

[0049] Fig. 11 shows a panel including a ToF sensor on a rail, according to an example embodiment of the present disclosure;

[0050] Fig. 12 shows a network architecture, according to an example embodiment of the present disclosure;

[0051] Fig. 13 shows a flow chart of a method, according to an example embodiment of the present disclosure; and

[0052] Fig. 14 shows an example embodiment of a computing system for implementing certain aspects of the present technology.

[0053] The figures are intended for illustrative purposes only, and do not serve as restriction of the scope of the protection as laid down by the claims. DETAILED DESCRIPTION

[0054] It will be readily understood that the components of the embodiments as generally described herein and illustrated in the appended figures could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the present disclosure, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0055] The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the present disclosure is, therefore, indicated by the appended claims rather than by this detailed description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

[0056] Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single example of the present disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Thus, discussions of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same example.

[0057] Furthermore, the described features, advantages, and characteristics of the present disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the present disclosure can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the present disclosure. Reference throughout this specification to "one embodiment," "an embodiment," or similar language means that a particular feature, structure, or characteristic described in connection with the indicated embodiment is included in at least one embodiment of the present disclosure. Thus, the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0058] A 3D ToF sensor may have a FoV determined by its design. In the example of Fig. 1, a 3D ToF sensor 100 has a 63° diagonal square FoV 102. When a ToF sensor 200, e.g., the 3D ToF sensor 100, is mounted on a ceiling 212 of a room 210, e.g., 2.4m above a floor 214 such as shown in the example of Fig. 2, the ToF sensor 200 may detect an area 202 of 2.1m x 2.1m square meter (i.e., 2.4m*tan(63° / 2)*sqrt(2)~2.1m) on the floor 214. When a person in the room fell and is lying on the floor 214, if the whole or part of the person’s body is within the 2. Im x 2. Im FoV area 202, then the ToF sensor 200 may detect that the person has fallen. The detection area of a ToF fall detection sensor 200 may thus be defined as the sensor’s maximum coverage area 202 on the floor 214.

[0059] The ToF sensor 100, 200 may be communicatively connected to a backend system (not shown), where detected events may be processed and logged and where actions may be triggered based on detected events.

[0060] The ToF sensor may be a standalone sensor. The ToF sensor 100, 200 may be combined with one or more other sensors. The ToF sensor 100, 200 may be integrated with a first device, e.g., a luminaire. When integrated with a first device, the ToF sensor 100, 200 may be physically included in the same housing as the first device but functionally separated, e.g., only sharing mains power but no communication or control between the ToF sensor 100, 200 and the first device. Alternatively, when integrated with a first device, the ToF sensor 100, 200 may be physically included in the same housing as the first device and functionally connected, e.g., sharing mains power and having communication and / or control functions between the ToF sensor 100, 200 and the first device.

[0061] In an example embodiment, the ToF sensor 100, 200 may be integrated in the housing of a luminaire. The luminaire may be designed for mounting on a ceiling.

[0062] In a preferred embodiment, a luminaire with integrated ToF sensor 100, 200 may be designed for installation in a ceiling system, e.g., a suspended ceiling. An example of a first device in the form of a rectangularly shaped panel 320 for installation in a ceiling system is shown in Fig. 3. In Fig. 3 the front view of the panel 320 is shown. The panel 320 may include a ToF sensor 300 and a luminaire 322. In this example, the panel 320 is rectangularly shaped, but the panel 320 may have any other shape fitting the construction and / or design of the ceiling system. In this example, the luminaire 322 is rectangularly shaped, but the luminaire 322 may have any other shape.

[0063] In the example of Fig. 3, the ToF sensor 300 may be integrated under the frame of the panel 320, e.g., with a hole through the frame to provide line-of-sight for the sensor. Alternatively, the ToF sensor 300 may be integrated in the frame of the panel 320, e.g., having its surface level with the plane of the panel 320. Alternatively, part or whole of the ToF sensor 300 may extend from the frame, e.g., by being installed on the outside of the front view of the panel 320. The ToF sensor 300 may be integrated with the luminaire 322 instead of a panel 320, in which case the luminaire with integrated ToF sensor 300 may be installed on a panel 320 or no panel is present.

[0064] When a panel with a fall detection function, e.g., panel 320, or a luminaire with integrated ToF sensor is installed on or in the ceiling of a room, the user typically wants to know the detection area (i. e. , FoV of the ToF) to make sure that all or most of the floor area is covered. If there is floor area not covered by the ToF sensor, the user may adjust the position or orientation of the panel or luminaire with integrated ToF sensor to thereby change the position of the ToF sensor. An example hereof is shown in Fig. 4A and Fig. 4B, where a top view of a room 410 is shown.

[0065] In the example of Fig. 4A and Fig. 4B, the room 410 may be a bathroom, including a floor area 414, and a first object 416 (in this example a toilet 416) and a second object 418 (in this example a wash basin 418) placed on the floor area 414. A panel 420, e.g., the panel 320 of Fig. 3, including a ToF sensor 400 and possibly including a luminaire 322, may be installed in or on the ceiling of the room 410. The rectangle box around the floor area 414 represents the borders (i.e., walls) of the room 410.

[0066] In the example of Fig. 4A, the position and orientation of the panel 420 results in a FoV 402A (depicted by the dashed box) of the ToF sensor 400. In Fig. 4A the FoV 402A does not cover the whole floor area 414. By adjusting the orientation of the panel 420, in this example by rotating the panel 420 by 180° resulting in a displacement of the ToF sensor 400 as shown in Fig. 4B, all floor area 414 may be covered by the detection area, i.e., FoV 402B, of the ToF sensor 400.

[0067] The ToF sensor 400 may advantageously be used for fall detection, most advantageously for the detection of elderly people falling. In this use case the ToF sensor may also be referred to as fall detection sensor.

[0068] The present application enables visualizing the detection area (e.g., FoV 202, 402A, 402B) of a ceiling mounted ToF sensor (e.g., ToF sensor 200, 300, 400). In a preferred embodiment, the ToF sensor may be integrated with a luminaire (e.g., luminaire 322), possibly using a panel (e.g., panel 320, 420). The detection area of the ToF sensor may be visualized on a display device of a user, e.g., a smartphone or tablet, further enabling the user to adjust the positioning of the ToF sensor on the ceiling to achieve an optimal detection area. An app on the user’s device may provide instructions for determining a current detection area of the ToF sensor and recommendations for repositioning the ToF sensor, e.g., by rotating a panel such as panel 420 in the example of Fig. 4A and Fig. 4B. Thus, the ToF sensor may be optimally placed on the ceiling for an optimal FoV of the ToF sensor.

[0069] In the following examples, a ToF sensor is integrated with a panel further including a luminaire, hereinafter also referred to as panel luminaire. Alternatively, the ToF may be integrated with a luminaire without a panel. In another alternative, the ToF sensor may be a stand alone sensor or integrated with any other device. When integrated with a panel or luminaire, the ToF sensor may advantageously be repositioned by rotating the panel or luminaire, e.g., by 90°, 180° or 270° in case of a rectangular or square shaped panel or luminaire such as shown in the example of Fig. 4A and Fig. 4B.

[0070] With a panel luminaire having known dimensions, the detection area of the ToF sensor may be determined by fusion of data from the ToF sensor in the panel luminaire and image data from a camera of the user’s device, in this example a smartphone. Data fusion may be performed by a processor of the smartphone to derive the detection area of the ToF sensor. The detection area of the ToF sensor may be visually overlayed on an image of the floor, e.g., using augmented reality through the camera of the smartphone where the image of the floor is overlayed with lines indicating the detection area of the ToF sensor. Furthermore, suggestion on how to adjust the position and / or orientation of the panel luminaire may be provided on the smartphone to maximize the floor area covered by the ToF sensor.

[0071] In an example embodiment, a user may be in a room, e.g., bathroom, standing in proximity of a panel luminaire. The user may open a ToF sensor calibration app (hereinafter referred to as app), which may activate a camera of the smartphone. The user may point the camera towards the panel luminaire on the ceiling. In the example of Fig. 5 A, a panel luminaire 520 including a ToF sensor 500 and a luminaire 522 may be the major object in a camera view 530 of the smartphone. Also shown in the camera view 530 are some further panels of a ceiling system 512. The panel luminaire 520 may be recognized through image recognition routines in the app, as well as the position of the ToF sensor 500 on the panel luminaire 520.

[0072] Optionally, a boxed frame 532 such as shown in Fig. 5B may be overlayed on the image to outline the detected panel luminaire 520. In an example embodiment, the user may manually adjust the frame 532 to make it match together with the edges of the panel luminaire 520, e.g., through the app allowing the edges and / or comers of the frame 532 to be moved using a user interface of the smartphone.

[0073] In an example embodiment, the model of the panel luminaire 520 may be automatically recognized by the app from the camera view 530, and the dimensions of the panel luminaire 520 may be obtained from specifications of the model. The specifications may be stored in the smartphone accessible to the app. Alternatively, the app may contact a backend system for obtaining the model information and in particular the information about the dimension of the panel luminaire 520.

[0074] If the model of the panel luminaire 520 cannot be recognized, or when the app is not configured to automatically recognize the panel luminaire 520, the user may be asked to enter an identification of the model manually or provide the dimensions of the luminaire manually.

[0075] With reference to Fig. 6, the user may adjusts his / her standing position and / or the camera pointing direction, so that the camera view 630 includes not only the panel luminaire 620, e.g., panel luminaire 520, on the ceiling 612 but also the surface of the wall in front of the user (front wall 634) and the surface of the wall at the left side or right side of the user (side wall 636). Also shown in the camera view 630 is a toilet 616 located in the bathroom. Knowing the actual dimension of the panel luminaire 620 (e.g., 30cm x 30cm), the ceiling 612 being a horizontal plane, and the angle of the camera from build in sensors (e.g., gyroscope) of the smartphone, the processor of the smartphone may precisely calculate the distance between the ToF sensor 600 and the intersection of the ceiling 612 and the front wall 634 (i.e., distance dl) and the distance between the ToF sensor 600 and the intersection of the ceiling and the side wall 636 (i.e., distance d2). Hereto, the intersections between the walls and the ceiling may be determined by the app through image recognition software on the smartphone.

[0076] With reference to Fig. 7, knowing dl and d2 from the procedure of Fig. 6, the processor of the smartphone may then virtually mark a projection 700 of the ToF sensor 600 on the floor in the camera view 730. The user may further adjust his / her standing position and / or the camera pointing direction, so that the camera view 730 includes not only the front wall 634 and the side wall 636 but also the floor area 716 intersecting with the two walls 634, 636. Because of possible space limitation in the room, the camera view 730 may not be able to include the ceiling.

[0077] To get the projection 700 of the ToF sensor 600 on the floor, the processor of the smartphone may construct two lines 740, 742 on the floor in the camera view 730. One line 740 may be in parallel with the intersection of the floor 716 and the front wall 634 having a distance of dl between them. The other line 742 may be in parallel with the intersection of the floor 716 and the side wall 636 having a distance of d2 between them. The intersection of lines 740 and 742 then determines the location of the projection 700 of the

[0078] ToF sensor 600.

[0079] To precisely determine dl and d2 in the camera view 730, a reference object 616, of which the actual dimension may be determined by the ToF sensor, may be used. In the example of Fig. 7, the object 616 is a toilet. The ToF sensor 600 may measure the distance to the object 616 precisely. By also measuring the distance from the ToF sensor 600 to the floor 716, the actual height ht of the toilet 616 can be calculated as the distance to the floor 716 minus the distance to the toilet 616. Not that in the example of Fig. 7, the height of the toilet seat part of the toilet is measured. Instead of toilet 616 any other object in the room may be used as reference object. Preferably, the reference object has a flat surface area for more accurate measurement of the distance to the ToF sensor 600.

[0080] With reference to Fig. 8, knowing the height of the ceiling hc, the side length (L) of the area ABCD representing the detection area (similar to 202 in Fig. 2) of the ToF sensor 600 may be calculated as follows: L = hc* tan(l / 2* FoVdiagonai) * sqrt(2).

[0081] To visualize the detection area, the smartphone may draw a frame on the floor in the camera view 730, depicted in Fig. 8 as the dashed box ABCD. The side length of the frame ABCD may be L and the projection 700 of the ToF sensor 600 on the floor 716 may be at the center of the frame ABCD. It is possible that the distance between the projection 700 of the ToF sensor 600 and a wall of the room is smaller than L / 2, e.g., d3 as shown in Fig. 8. In this case the frame ABCD may have a shape different from a square, i.e., rectangular. For illustration purpose, in Fig. 8 which is the same camera view 730 as Fig. 7, dl is smaller than L / 2, while d2 is larger than L / 2.

[0082] The frame ABCD may represents the detection area of the ToF sensor 600. In the example of Fig. 8, the length of AB is (d3 + L / 2) and the length of AC is (dl + L / 2). d3 is the distance between the projection 700 of the ToF sensor 600 and the right border of the room. In this example, d3 is smaller than L / 2 and dl is also smaller than L / 2.

[0083] In the example of Fig. 8, since dl is smaller than L / 2, the ToF sensor 600 may be moved away from the front wall 634. Since d2 is larger than L / 2 while d3 is smaller than L / 2, the ToF sensor 600 may be moved closer to the side wall 636. This may be realized, e.g., by rotating the panel luminaire 620 by, in this example, 90° as illustrated in Fig. 9A and Fig. 9B, which show a top view from above the ceiling of the panel luminaire 620. In this example, the orientation of the panel luminaire 620 including ToF sensor 600A results in the frame ABCD of Fig. 8 being covered by the ToF sensor 600A. In Fig. 9C the projection of the ToF sensor 600A on the floor is depicted as 700A, which corresponds to the projection 700 of Fig. 8. Rotating the panel luminaire 620 in the ceiling by 90°, as shown in Fig. 9B, results in the ToF sensor 600B having its projection at location 700B on the floor. In this example, ToF sensors 600A and 600B are one and the same, but differently labeled to illustrate the different locations of the ToF sensor. As illustrated in Fig. 9C, the projection 700A is the original position of the projection of the ToF sensor while the projection 700B is the new position of the projection of the ToF sensor after the rotation. Frame EFGH is the updated detection area of the ToF sensor 600, 600B after the rotation. In this example, the frame EFGH is almost a square with side lengths L, covering more floor area compared to the frame ABCD.

[0084] The panel including the ToF sensor may be shaped such to allow repositioning of the panel in or on the ceiling to enable an optimal detection area for the ToF sensor, such as detection area EFGH in Fig. 9C. Panel luminaire 620 is an example of a square panel that may be repositioned by rotating the panel 90°, 180° or 270° to reposition the ToF sensor 600A, 600B. Other non-limiting examples are shown in Fig. 10A where a ToF sensor 1000 A is located in the comer of a square panel 1020A allowing repositions by 90°, 180° or 270°, in Fig. 10B where a ToF sensor 1000B is located on one edge of a rectangular panel 1020B allowing repositions by 180°, in Fig. 10C where a ToF sensor 1000C is located on one edge of a hexagonal panel 1020C allowing repositions by 30°, 60°, 90°, 120° or 150°, and in Fig. 10D where a ToF sensor WOOD is located on the edge of a circular panel 1020D allowing repositions at any angle.

[0085] The panels 1020A-D may include a luminaire, in which case the panels may be referred to as luminaire panels.

[0086] A panel may include a smart luminaire, in which case the ToF sensor may include functionality for controlling the luminaire.

[0087] In the above examples, a panel includes a ToF sensor which position may be changed by changing the orientation of the panel. Alternatively, a ToF sensor 1100B may be installed on a rail 1124 or any other movable means on or behind a panel 1120, such as shown in Fig. 11. The rail 1124 may allow the ToF sensor 1100B to be repositioned automatically along the rail 1124, e.g. from a position 1100A to the location of the ToF sensor 1100B in Fig. 11.

[0088] A ToF sensor may include a processor and a memory for performing measurements as described in the above examples. With reference to Fig. 12, a ToF sensor 1200 may interact with a user’s device 1250 for further measurements using a camera of the user’s device as described in the above examples, e.g., using an augmented reality mode of the camera. The user’s device 1250 may use the measurement data from the ToF sensor 1200 to, combined with its own measurement data, determine an optimal orientation of a panel and therewith an optimal detection area of the ToF sensor 1200 in the panel. The panel may then be adjusted manually or the location of the ToF sensor 1200 in the panel may be changed automatically, e.g., as shown in Fig. 11.

[0089] The ToF sensor 1200 and a user’s device 1250 may be communicatively connected via a wireless communication link 1254. The ToF sensor 1200 and the user’s device 1250 may be connected to a same communication network for exchanging data between the ToF sensor and the user’s device. The ToF sensor may be communicatively connected via communication link 1256 to a remote computer system or controller device 1252 to support the ToF sensor in the measurements and / or for interaction with the user’s device 1250 via another communication link 1258.

[0090] Fig. 13 shows a flow chart of an example method 1300 of the present disclosure.

[0091] In step 1302, the dimensions of a ceiling mounted panel (e.g., panel luminaire 320, 420, 520, 620 or panel 1020A-D) may be obtained, e.g., as described in the examples of Fig. 5A and 5B.

[0092] In step 1304, based on the dimensions of the panel, distances dl and d2 of the ToF sensor (e.g., ToF sensor 300, 400, 500, 600, 600A, 600B, 1000A-D, 1100B) in the panel to two intersecting walls (e.g., front wall 634 and side wall 636 in Fig. 6) of the room may be determined using a camera on the user’s device (e.g., a smartphone).

[0093] In step 1306, the ToF sensor may be used to determine a height (e.g., ht) of a reference object (e.g., object 416, 418, 616) on the floor of the room, e.g., as described in the example of Fig. 7.

[0094] In step 1308, using the determined height of the reference object, distances dl and d2 may be applied to the floor using the camera of the user’s device, e.g., as described in the example of Fig. 7. Hereto, a location on the floor of a projection (e.g., projection 700, 700A) of the ToF sensor may be determined and used.

[0095] In step 1310, using a ceiling height measured by the ToF sensor, a side length L of the detection area (e.g., ABCD in Fig. 8) of the ToF sensor may be determined. The detection area may be drawn on the display of the user’s device, e.g., using augmented reality and the camera view. Thus, the user may see the detection area ABCD on the floor with the projection of the ToF sensor at the center of the area ABCD. In step 1312, in case the distance of the ToF sensor to any wall of the room is larger than half of the side length L of the detection area ABCD, the user’s device may show a suggestion on the display on how to adjust the position / orientation of the panel (e.g., as shown in Figs. 9A-9C) to updated / improve the detection area. The resulting improved detection (e.g., area EFGH in Fig. 9A) may be visualized on the display of the user’s device after the adjustment.

[0096] Instead of manually rotating the panel luminaire as in step 1312, an alternative step 1314 may include an automatic repositioning of the ToF sensor, e.g. along a rail 1124, based on the measurements in steps 1302-1310.

[0097] In the above examples, references are made to a floor. It will be understood that any other desired detection area may be used as a base surface of the room instead.

[0098] Fig. 14 shows an example embodiment of a computing system 1400 for implementing certain aspects of the present technology. In various examples, the computing system 1400 can be any computing device making up the ToF sensor 300, 400, 500, 600, 600A, 600B, 1000A-D, 1100B, a central computer or controller 1252 working with the ToF sensor, a user’s device 1250 such as a smartphone, or any other computing based system described herein. The computing system 1400 may be implemented in a panel luminaire, such as panel luminaire 320, 520, 520, 620.

[0099] In some implementations, a computing system 1400 can implement the methods described herein, such as method 1300 shown in Fig. 13.

[0100] The computing system 1400 can include any component of a computing system described herein which the components of the system are in communication with each other using connection 1405. The connection 1405 can be a physical connection via a bus, or a direct connection into processor 1410, such as in a chipset architecture. The connection 1405 can also be a virtual connection, networked connection, or logical connection.

[0101] In some implementations, the computing system 1400 may be a distributed system in which the functions described in this disclosure can be distributed within a datacenter, multiple data centers, a peer network, etc. In some embodiments, one or more of the described system components represents many such components each performing some or all of the functions for which the component is described. In some embodiments, the components can be physical or virtual devices.

[0102] The example system 1400 may include at least one processing unit (CPU or processor) 1410 and a connection 1405 that couples various system components including system memory 1415, such as read-only memory (ROM) 1420 and random-access memory (RAM) 1425 to processor 1410. The computing system 1400 can include a cache of highspeed memory 1412 connected directly with, in close proximity to, or integrated as part of the processor 1410.

[0103] The processor 1410 may include any general-purpose processor and a hardware service or software service, such as services 1432, 1434, and 1436 stored in storage device 1430, configured to control the processor 1410 as well as a special-purpose processor where software instructions are incorporated into the actual processor design. The processor 1410 may essentially be a completely self-contained computing system, containing multiple cores or processors, a bus, memory controller, cache, etc. A multi-core processor may be symmetric or asymmetric.

[0104] To enable user interaction, the computing system 1400 may include an input device 1445, which can represent any number of input mechanisms, such as a microphone for speech, a touch-sensitive screen for gesture or graphical input, keyboard, mouse, motion input, speech, etc. The computing system 1400 may also include an output device 1435, which can be one or more of a number of output mechanisms known to those of skill in the art. In some instances, multimodal systems can enable a user to provide multiple types of input / output to communicate with the computing system 1400. The computing system 1400 may include a communications interface 1440, which can generally govern and manage the user input and system output. There is no restriction on operating on any particular hardware arrangement, and therefore the basic features here may easily be substituted for improved hardware or firmware arrangements as they are developed.

[0105] A storage device 1430 can be a non-volatile memory device and can be a hard disk or other types of computer readable media which can store data that are accessible by a computer, such as magnetic cassettes, flash memory cards, solid state memory devices, digital versatile disks, cartridges, random access memories (RAMs), read-only memory (ROM), and / or some combination of these devices.

[0106] The storage device 1430 may include software services, servers, services, etc., that when the code that defines such software is executed by the processor 1410, it causes the system to perform a function. In some embodiments, a hardware service that performs a particular function can include the software component stored in a computer-readable medium in connection with the necessary hardware components, such as a processor 1410, a connection 1405, an output device 1435, etc., to carry out the function.

Claims

CLAIMS:

1. A method of determining a detection area of a Time-of-Flight, ToF, sensor (300, 400, 500, 600, 600 A, 600B, 1000A-D, 1100B) mounted on a ceiling of a room, the ToF sensor being included in a first device (320, 420, 520, 620, 1020A-D) having predefined dimensions, the method comprising: obtaining (1002) the predefined dimensions of the first device in a second device (1250); obtaining a first image of the room comprising the first device using a camera of the second device; obtaining a second image of the room comprising a desired detection area using the camera; determining a projection of the ToF sensor on the second image based on the predefined dimensions of the first device; determining (1006), using the ToF sensor, a height (ht) of a reference object (416, 418, 616) on the desired detection area in the room; and determining (1010) a current detection area (ABCD) of the ToF sensor based on the determined height of the reference object and a distance between the ToF sensor and the desired detection area measured by the ToF sensor and detection angle range of the ToF sensor; wherein the method further comprising: displaying the second image on a display of the second device and overlaying the current detection area (ABCD) of the ToF sensor on the second image.

2. The method according to claim 1, wherein the first image is a first camera image from a two-dimensional (2D) camera of the second device, wherein determining (1004), using the first camera image and based on the predetermined dimensions of the first device, a first distance (dl) between the ToF sensor and a first wall (634) and a second distance (d2) between the ToF sensor and a second wall (636), wherein the first wall intersects the second wall,and wherein determining the projection of the ToF sensor on the second image is based on the first distance and the second distance.

3. The method according to any one of the preceding claims, further comprising determining (1012) a repositioning of the ToF sensor for obtaining an improved detection area (EFGH).

4. The method according to any one of the preceding claims, wherein the first image includes at least a part of the ceiling including the first device, at least a part of the first wall and at least a part of the second wall.

5. The method according to any one of the preceding claims, wherein the second image includes at least a part of the desired detection area including the reference object, at least a part of the first wall and at least a part of the second wall.

6. The method according to any one of the claims 1-5, further comprising displaying an instruction on a display of the second device for repositioning the first device to obtain the improved detection area (EFGH).

7. The method according to any one of the claims 1-5, further comprising automatically repositioning the ToF sensor by moving the ToF sensor along a rail (1124) to obtain the improved detection area (EFGH).

8. The method according to any one of the preceding claims, wherein the first device is a light fixture comprising the ToF sensor and a luminaire.

9. A calibration system for determining a detection area of a Time-of-Flight, ToF, sensor (300, 400, 500, 600, 600 A, 600B, 1000A-D, 1100B) mounted on a ceiling of a room, the system comprising a first device (320, 420, 520, 620, 1020A-D) comprising the ToF sensor and a second device (1250) comprising a camera, a display and a processor, the first device having a predefined dimension, wherein the second device is configured to: obtaining (1002) the predefined dimensions of the first device;obtaining a first image of the room comprising the first device using the camera; obtaining a second image of the room comprising a desired detection area using the camera; determining a projection of the ToF sensor on the second image based on the predefined dimensions of the first device; wherein the first device is configured to determine (1006), using the ToF sensor, a height (ht) of a reference object (416, 418, 616) on the desired detection area in the room; and transmit the determined height of the reference object to the second device; wherein the second device is further configured to determine (1010) a current detection area (ABCD) of the ToF sensor based on the determined height of the reference object and a distance between the ToF sensor and the desired detection area measured by the ToF sensor and detection angle range of the ToF sensor; and display the second image and overlaying the current detection area (ABCD) of the ToF sensor on the second image.

10. The calibration system according to claim 9, wherein the first device is repositionable to reposition the ToF sensor based on the determination of an improved detection area (EFGH) of the ToF sensor determined by the second device.

11. The calibration system according to claim 9 or claim 10, wherein the ToF sensor is movably connected to the first device, and wherein the ToF sensor is repositionable based on the determination of the improved detection area (EFGH) of the ToF sensor determined by the second device.

12. The calibration system according to any one of the claims 9-11, wherein the first device is a light fixture comprising the ToF sensor and a luminaire.

13. A computer program comprising instruction which, when the program is executed by one or more processors, cause the one or more processors to carry out the method according to any one of the claims 1-8.

14. A computer-readable storage medium comprising instructions which, when executed by one or more processors, cause the one or more processors to carry out the method according to any one of the claims 1-8.

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