Depth camera and mobile robot

Abstract

The invention provides a depth camera and a mobile robot. The depth camera comprises a line laser emitting unit used for emitting a plurality of line laser beams with preset widths; the dot matrix emitting unit is arranged on the side of the line laser emitting unit and used for emitting dot matrix light beams, the dot matrix emitting unit comprises multiple rows of dot matrix light sources, and at least two rows of dot matrix light sources are regularly arranged in a staggered mode and are circularly arranged; the optical element is arranged on the light emitting path of the line laser emitting unit and the dot matrix emitting unit, the line laser beam projects a dodging pattern to a to-be-detected space through the optical element for close-range detection, and the dot matrix beam projects a speckle pattern to the to-be-detected space through the optical element; and the receiving unit is arranged on the side of the line laser emitting unit and the dot matrix emitting unit. The depth camera of the invention can obtain the obstacle avoidance depth information at a short distance, realizes high-precision obstacle avoidance at a short distance, identifies black material objects and small objects, can also realize three-dimensional positioning navigation and three-dimensional height measurement, and solves the problem of multiple paths.

Description

Technical Field

[0001] The present application relates to the field of depth acquisition technology, and in particular to a depth camera and a mobile robot. Background Art

[0002] With the gradual development of technologies such as machine vision and autonomous driving, more and more applications use depth cameras for object recognition and scene modeling. It can be said that depth cameras are the eyes of robots. There are currently three common depth camera solutions on the market: structured light cameras, binocular cameras, and time-of-flight (TOF) cameras. The above three depth cameras have different principles and are applicable to different application scenarios. They often need to cooperate with each other to meet the needs of complex application scenarios.

[0003] For example, when mobile robots implement mapping and navigation functions, they mainly use LDS (Laser Direct Structuring) to achieve two-dimensional mapping and navigation; when mobile robots implement obstacle avoidance functions, they mainly use TOF technology to detect the depth information of objects at close range in order to achieve close-range obstacle avoidance and recognition functions. In addition, they cannot accurately measure the height of low objects in space. However, existing mobile robots cannot simultaneously perform stereo positioning and navigation, close-range high-precision obstacle avoidance, and stereo height measurement. Summary of the invention

[0004] In view of the above, it is necessary to propose a depth camera and a mobile robot to solve the problem that the existing depth camera cannot simultaneously achieve stereo positioning navigation, close-range high-precision obstacle avoidance and stereo height measurement.

[0005] According to a first aspect of an embodiment of the present application, there is provided a depth camera, comprising: a line laser emitting unit, for emitting a plurality of line laser beams of a preset width, wherein the plurality of line laser beams do not intersect in a projection area and have an angle with the vertical direction of less than 30 degrees, and at least one of the line laser beams has an angle with the vertical direction of greater than 0 degrees in the projection area; a dot matrix emitting unit, disposed on the side of the line laser emitting unit, for emitting dot matrix beams, wherein the dot matrix emitting unit comprises a plurality of rows of dot matrix light sources, wherein at least two rows of the dot matrix light sources are regularly staggered and cyclically arranged; an optical element, disposed in the light emitting path of the line laser emitting unit and the dot matrix emitting unit, wherein the line laser beam passes through a projection area of ​​the line laser emitting unit. A uniform light pattern is projected toward the space to be measured through the optical element for close-range detection, and the dot matrix light beam projects a speckle pattern toward the space to be measured through the optical element, and both the uniform light pattern and the speckle pattern are projected into an obstacle avoidance area for obstacle avoidance, and the speckle pattern is projected into a navigation area for navigation; a receiving unit is arranged on the side of the line laser emitting unit and the dot matrix emitting unit, and is used for receiving light signals corresponding to the uniform light pattern and the speckle pattern to obtain close-range obstacle avoidance depth information, thereby performing stereo height measurement and close-range obstacle avoidance, and for receiving light signals corresponding to the speckle pattern to obtain navigation depth information, thereby performing stereo positioning navigation.

[0006] In the depth camera provided by the embodiment of the present application, multiple line laser beams do not intersect in the projection area and the angle between them and the vertical direction is less than 30 degrees, at least one of the line laser beams has an angle greater than 0 degrees between it and the vertical direction in the projection area, the dot matrix emitting unit includes multiple rows of dot matrix light sources, at least two rows of dot matrix light sources are regularly staggered and cyclically arranged, the uniform light pattern and the speckle pattern are both projected on the obstacle avoidance area for obstacle avoidance, the speckle pattern is projected on the navigation area for navigation, and the depth information obtained by the projection of multiple line laser beams is mainly used for close-range detection, and the area not covered by the line laser beam can be covered by the dot matrix light. The depth information obtained by beam projection can be used as a supplement to obtain more complete obstacle contour information, achieve high-precision obstacle avoidance at close range, solve the problems of close-range blind spots, multi-paths, black material recognition, and small object recognition, and at the same time have the characteristics of high precision; and the depth information obtained by using dot matrix beam projection during long-distance detection can be used for stereo positioning navigation. Since at least two rows of dot matrix light sources in the multiple rows of dot matrix light sources are regularly staggered and arranged in a cycle, the interval blind spot between two adjacent dot matrix light sources in each row of dot matrix light sources can be supplemented by the dot matrix light sources in the next row, thereby making the resolution of the depth camera higher. In addition, through the cooperation of the line laser emitting unit and the dot matrix emitting unit, the depth information obtained by the projection of multiple line laser beams and the depth information obtained by the projection of dot matrix beams can complement each other, and the objects in the space can be measured in stereo with high precision.

[0007] In a possible implementation, when the multiple line laser light beams are projected into the space to be measured, the height information of the obstacles in the space to be measured can be obtained; when the dot matrix light beams are projected into the space to be measured, the contour information of the obstacles in the space to be measured can be obtained; and the receiving unit receives light signals corresponding to the height information and the contour information to perform stereo height measurement.

[0008] In the solution provided in the embodiment of the present application, the height information of the obstacles in the space to be measured is obtained when multiple line laser beams are projected into the space to be measured, and the contour information of the obstacles in the space to be measured is obtained when the dot matrix beams are projected into the space to be measured. The receiving unit processes the optical signals corresponding to the height information and the contour information, and can perform stereoscopic height measurement of the obstacles in the space to be measured.

[0009] In a possible embodiment, the depth camera also includes a substrate and a bottom plate, the substrate is arranged on one side of the bottom plate, the dot matrix emitting unit and the receiving unit are arranged on a side of the substrate away from the bottom plate, and the line laser emitting unit includes two line laser emitting modules, the two line laser emitting modules are arranged on the bottom plate and located on opposite sides of the substrate, wherein the two line laser emitting modules, the dot matrix emitting unit and the receiving unit are arranged side by side.

[0010] In the solution provided in the embodiment of the present application, by providing two line laser emission modules on the bottom plate and on opposite sides of the substrate, wherein the two line laser emission modules, the dot matrix emission unit and the receiving unit are arranged side by side, the space utilization rate can be improved, the cost is low and the appearance is more beautiful.

[0011] In a possible embodiment, the depth camera also includes a substrate and a bottom plate, the substrate is arranged on one side of the bottom plate, the dot matrix emitting unit and the receiving unit are arranged on a side of the substrate away from the bottom plate, and the line laser emitting unit includes two line laser emitting modules, the two line laser emitting modules are arranged on the bottom plate and located on opposite sides of the substrate, wherein the two line laser emitting modules and the substrate are arranged side by side in the horizontal direction, and the dot matrix emitting unit and the receiving unit are arranged side by side in the vertical direction.

[0012] In the solution provided in the embodiment of the present application, by providing two line laser emission modules on the bottom plate and on opposite sides of the substrate, wherein the two line laser emission modules, the dot matrix emission unit and the receiving unit are arranged side by side, the space utilization rate can be improved, the cost is low and the appearance is more beautiful.

[0013] In a possible implementation, the line laser emitting unit and the dot matrix emitting unit are alternately lit up in time-sharing to alternately project the uniform light pattern and the speckle pattern.

[0014] In the solution provided by the embodiment of the present application, by alternately lighting up the line laser emitting unit and the dot matrix emitting unit, mutual interference when the two light beams are irradiated at the same time can be avoided, ensuring that each light beam can be independently projected and received, thereby improving the accuracy and reliability of the measurement. If the two light beams are projected at the same time, they may overlap and interfere with each other in the space to be measured, making it difficult for the receiving unit to distinguish and accurately measure the light signal of each light beam. Alternating projection can avoid this interference and ensure that the measurement data of each light beam is independent and accurate.

[0015] In a possible implementation, the line laser emitting unit and the dot matrix emitting unit are two light sources.

[0016] In a possible embodiment, the line laser emitting unit and the dot matrix emitting unit are a light source, and the optical element includes a light uniformity functional area and a line laser functional area, the light uniformity functional area is used to shape a part of the light beam emitted by the light source into a light uniformity pattern, and the line laser functional area is used to shape another part of the light beam emitted by the light source into a speckle pattern.

[0017] In a possible embodiment, the photosensitive surface of the receiving unit includes a line laser receiving area and a dot matrix receiving area, the line laser receiving area is used to obtain a first depth image corresponding to when multiple line laser beams are turned on and off through the principle of triangulation ranging, and is used to obtain a second depth image corresponding to multiple line laser beams through the TOF ranging principle, and obtain the obstacle avoidance depth information based on the fused first depth image and the second depth image; the dot matrix light beam emitted by the dot matrix transmitting unit includes at least two different frequencies, and the at least two different frequencies are first short-exposed and then long-exposed in sequence, and the dot matrix receiving area is used to obtain a third depth image during the short exposure and a fourth depth image during the long exposure, and obtain the navigation depth information based on the third depth image and the fourth depth image.

[0018] In the solution provided in the embodiment of the present application, by acquiring the first depth image corresponding to when multiple line laser beams are turned on and off, and acquiring the second depth image corresponding to multiple line laser beams through the TOF ranging principle, the interference of background noise and ambient light can be effectively eliminated, and the accuracy of obstacle avoidance depth information can be improved. During short exposure, the depth image captured by the dot matrix receiving area mainly contains the details of the high-brightness area, which is suitable for processing surfaces with high reflectivity. During long exposure, the depth image captured by the dot matrix receiving area mainly contains the details of the low-brightness area, which is suitable for processing surfaces with low reflectivity. By receiving short-exposure and long-exposure depth images of different frequencies of the dot matrix transmitting unit, the dynamic range and signal-to-noise ratio problems can be effectively handled, and the reliability of navigation depth information can be improved.

[0019] In a possible implementation manner, the at least two different frequencies include a first frequency and a second frequency, the first frequency is greater than the second frequency, and a transmission sequence of the first frequency takes precedence over a transmission sequence of the second frequency.

[0020] In the solution provided in the embodiment of the present application, by preferentially transmitting the first frequency and then transmitting the second frequency, the data corresponding to the first frequency can be used when performing depth calculation, and the data corresponding to the second frequency can be used for period expansion, thereby ensuring the real-time nature of the depth data.

[0021] In a possible embodiment, the dot matrix transmitting unit includes one or more dot matrix transmitting areas, and the multiple dot matrix transmitting areas can be illuminated at one time or in sequence. The photosensitive surface of the receiving unit includes a line laser receiving area and a dot matrix receiving area. The line laser receiving area is used to collect light signals corresponding to the line laser light beam to obtain obstacle avoidance depth information, and the dot matrix receiving area is used to collect light signals corresponding to the dot matrix transmitting area in sequence to obtain navigation depth information.

[0022] In the solution provided in the embodiment of the present application, the dot matrix transmitting unit can be divided into one dot matrix transmitting area or into multiple dot matrix transmitting areas. The multiple dot matrix transmitting areas can be illuminated at one time or in sequence. The time-sharing transmission method in which the multiple dot matrix transmitting areas are illuminated in sequence can ensure that the light beams of each dot matrix transmitting area are independently projected and received, avoiding light beam overlap and interference caused by simultaneous transmission; the dot matrix receiving area of ​​the receiving unit collects the light signals corresponding to each dot matrix transmitting area, and can generate a high-density depth map, which can improve the accuracy and resolution of navigation depth information.

[0023] In a possible implementation, when the line laser emitting unit is turned on, only the corresponding line laser receiving area in the photosensitive surface of the receiving unit works and outputs; when the dot matrix emitting unit is turned on, both the line laser receiving area and the dot matrix receiving area in the photosensitive surface of the receiving unit work and output.

[0024] In the solution provided by the embodiment of the present application, when the line laser emitting unit is turned on, only the corresponding line laser receiving area in the photosensitive surface of the receiving unit works and outputs, so that the amount of data and processing time can be reduced. When the dot matrix emitting unit is turned on, both the line laser receiving area and the dot matrix receiving area in the photosensitive surface of the receiving unit work and output, so that the accuracy and reliability of the overall measurement are improved.

[0025] A second aspect of an embodiment of the present application provides a mobile robot, comprising: a robot body; and a depth camera as described in the above technical solution, wherein the depth camera is mounted on the robot body.

[0026] The mobile robot provided in the embodiment of the present application includes the above-mentioned depth camera, so the mobile robot also includes the technical effects of the above-mentioned depth camera. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of the mobile robot provided in an embodiment of the present application.

[0028] Figure 2 Schematic diagram of the structure of the depth camera provided in the embodiment of the present application.

[0029] Figure 3 yes Figure 2 A simulation diagram of the spatial projection scene of the line laser beam and dot matrix beam emitted by the depth camera in the figure.

[0030] Figure 4 yes Figure 2 An example of a line laser spot captured by the photosensitive chip in the depth camera shown.

[0031] Figure 5 yes Figure 1 A schematic structural diagram of the depth camera when the line laser emission unit includes two line laser emission modules.

[0032] Figure 6 yes Figure 1 Another structural schematic diagram of the depth camera when the line laser emission unit includes two line laser emission modules.

[0033] Figure 7 yes Figure 1 A layout diagram of multiple rows of dot matrix light sources of the dot matrix emitting unit of the depth camera.

[0034] Explanation of main component symbols: mobile robot 1000, depth camera 100, line laser emitting unit 10, line laser beam 101, line laser emitting module 11, dot matrix emitting unit 20, dot matrix beam 201, dot matrix light source 21, optical element 30, receiving unit 40, photosensitive chip 41, photosensitive surface 410, laser receiving area 411, dot matrix receiving area 412, optical lens 42, substrate 50, bottom plate 60, robot body 200. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0036] In the description of the present invention, it should be understood that the terms indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0039] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0040] See also Figure 1 The embodiment of the present application provides a mobile robot 1000, which includes a depth camera 100 and a robot body 200. The depth camera 100 is mounted on one side of the robot body 200. The depth camera 100 is used to provide the navigation depth information and obstacle avoidance depth information to the robot body 200, thereby realizing the navigation function and the obstacle avoidance function. It can be understood that although the robot body 200 of the mobile robot 1000 of the embodiment of the present application is taken as an example of a sweeping robot in the accompanying drawings, it is not limited to this and can also be implemented as other robots that need navigation and obstacle avoidance.

[0041] For details, please refer to Figure 2 and Figure 3 The depth camera 100 includes a line laser emitting unit 10 , a dot matrix emitting unit 20 , an optical element 30 and a receiving unit 40 .

[0042] The line laser emitting unit 10 is used to emit multiple line laser beams 101 of preset width, wherein the multiple line laser beams 101 do not intersect in the projection area and have an angle with the vertical direction of less than 30 degrees, and at least one of the line laser beams has an angle greater than 0 degrees with the vertical direction in the projection area, wherein the preset width of each laser beam is 1mm-4.5mm, and the position at the angle is set at a close distance to avoid obstacles at close range. Preferably, the multiple line laser beams 101 do not intersect in the projection area and have an angle of 10 degrees with the vertical direction. In some embodiments, one of the line laser beams 101 may have an angle of 0 degrees with the vertical direction, and the other line laser beams 101 may have an angle of 10 degrees with the vertical direction. In some embodiments, the angles of the multiple line laser beams 101 with the vertical direction in the projection area are all 10 degrees.

[0043] The dot matrix emitting unit 20 is arranged on the side of the line laser emitting unit 10, and is used to emit a dot matrix light beam 201. The dot matrix emitting unit 20 includes multiple rows of dot matrix light sources 21. At least two rows of dot matrix light sources 21 are regularly staggered and cyclically arranged. The projection areas of the multiple rows of dot matrix light sources partially overlap with the projection areas of the multiple line laser beams 101. In this embodiment, in at least two rows of dot matrix light sources 21, the central angular resolution of each row of the dot matrix light sources 21 is less than or equal to 2°, the edge angular resolution is less than or equal to 2.5°, and the edge angular resolution is greater than the central angular resolution. When the at least two rows of dot matrix light sources 21 are regularly and cyclically staggered, when looking down, the central angular resolution can reach less than or equal to 0.66°, and the edge angular resolution is less than or equal to 0.83°, thereby improving the resolution in the horizontal direction.

[0044] The optical element 30 is arranged in the light emitting path of the line laser emitting unit 10 and the dot matrix emitting unit 20. The line laser beam 101 passes through the optical element 30 to project a uniform light pattern toward the space to be measured for close-range detection. The dot matrix beam 201 passes through the optical element 30 to project a speckle pattern toward the space to be measured. Both the uniform light pattern and the speckle pattern are projected into the obstacle avoidance area for obstacle avoidance, and the speckle pattern is projected into the navigation area for navigation. In this embodiment, the obstacle avoidance area is a close-range detection area, and the navigation area is a long-range detection area. It can be understood that the uniform light pattern can also be projected into the navigation area.

[0045] The receiving unit 40 is arranged on the side of the line laser emitting unit 10 and the dot matrix emitting unit 20, and is used to receive light signals corresponding to the uniform light pattern and the speckle pattern to obtain close-range obstacle avoidance depth information, thereby performing stereo height measurement and close-range obstacle avoidance, and to receive light signals corresponding to the speckle pattern to obtain navigation depth information, thereby performing stereo positioning navigation.

[0046] In the depth camera 100 provided in the embodiment of the present application, the multiple line laser beams 101 do not intersect in the projection area and the angle with the vertical direction is less than 30 degrees, at least one of the line laser beams has an angle greater than 0 degrees with the vertical direction in the projection area, the dot matrix emitting unit includes multiple rows of dot matrix light sources, at least two rows of dot matrix light sources are regularly staggered and cyclically arranged, the uniform light pattern and the speckle pattern are both projected on the obstacle avoidance area for obstacle avoidance, the speckle pattern is projected on the navigation area for navigation, and the depth information obtained by the projection of multiple line laser beams is mainly used for close-range detection, and the area not covered by the line laser beam can be projected by the dot matrix beam The acquired depth information can be used as a supplement to obtain more complete obstacle contour information, achieve high-precision obstacle avoidance at close range, solve the problems of close-range blind spots, multi-paths, black material recognition, and small object recognition, and at the same time have the characteristics of high precision; and the depth information obtained by using the dot matrix beam projection during long-distance detection can be used for stereo positioning navigation. Since at least two rows of dot matrix light sources 21 in the multiple rows of dot matrix light sources 21 are regularly staggered and arranged in a cycle, the interval blind area between two adjacent dot matrix light sources 21 in each row of dot matrix light sources 21 can be supplemented by the dot matrix light sources 21 in the next row, so that the resolution of the depth camera 100 is higher. In addition, through the cooperation of the line laser emitting unit 10 and the dot matrix emitting unit 20, the depth information obtained by the projection of multiple line laser beams 101 and the depth information obtained by the projection of the dot matrix beam 201 can complement each other, and the objects in the space can be measured in stereo with high precision.

[0047] It can be understood that the line laser emitting unit 10 adopts triangulation parallax measurement technology. When the line laser beam 101 reaches the surface of the obstacle, the receiving unit 40 collects the reflected line laser information, and then according to the change of the line laser information caused by the obstacle, the distance between the line laser emitting module and the obstacle in front of it can be calculated by trigonometric function using the principle of triangulation; so that the mobile robot 1000 can judge whether there is an obstacle in front according to the deformation of the line laser, thereby realizing the obstacle avoidance function.

[0048] The dot matrix emitting unit 20 adopts TOF measurement technology. The emission band of the line laser emitting unit 10 and the dot matrix emitting unit 20 is the same. The time of flight method (TOF) is to measure the three-dimensional structure or three-dimensional contour of the environmental target by measuring the time interval t from the emission to the reception of the pulse signal emitted by the dot matrix emitting unit 20 (often referred to as the direct time of flight method, Direct TOF, referred to as D-TOF) or the phase generated by the dot matrix light beam 201 going back and forth to the environmental target once (often referred to as the indirect time of flight method, Indirect TOF, referred to as I-TOF). In this embodiment, the duty cycle of the line laser emitting unit 10 is greater than the duty cycle of the dot matrix emitting unit 20.

[0049] In a possible implementation, when multiple line laser beams are projected into the space to be measured, height information of obstacles in the space to be measured can be obtained, and when dot matrix beams are projected into the space to be measured, contour information of obstacles in the space to be measured can be obtained. The receiving unit receives light signals corresponding to the height information and contour information to perform stereo height measurement.

[0050] In the solution provided in the embodiment of the present application, the height information of the obstacles in the space to be measured is obtained when multiple line laser beams are projected into the space to be measured, and the contour information of the obstacles in the space to be measured is obtained when the dot matrix beams are projected into the space to be measured. The receiving unit processes the optical signals corresponding to the height information and the contour information, and can perform stereoscopic height measurement of the obstacles in the space to be measured.

[0051] The receiving unit 40 includes a photosensitive chip 41 and an optical lens 42 disposed in the photosensitive path of the photosensitive chip 41, so that the light signal is first received by the optical lens 42 and then modulated by the photosensitive chip 41 to obtain depth information. The photosensitive chip 41 can be an I-TOF chip or a D-TOF chip.

[0052] See also Figure 4 The photosensitive surface 410 of the photosensitive chip 41 of the receiving unit 40 includes a line laser receiving area 411 and a dot matrix receiving area 412. The line laser receiving area 411 is used to receive the light signal corresponding to the line laser beam 101 to collect grayscale information and calculate the obstacle avoidance depth information; the dot matrix receiving area 412 is used to receive the light signal corresponding to the dot matrix beam 201 to obtain the navigation depth information.

[0053] In this embodiment, there are two laser beams, the projection areas of the two laser beams are vertical and arranged at an angle, and the projection areas of the multiple rows of dot matrix light sources partially overlap with the two line laser beams 101 in the projection areas.

[0054] The dot matrix transmitting unit 20 is used to project the dot matrix light beam 201 horizontally so as to project it into a farther area, so as to meet the needs of mapping and navigation applications. The emission wavelength range of the dot matrix transmitting unit 20 is 850nm~1200nm, and 940±15nm is preferred. The optical power of the dot matrix transmitting unit 20 is greater than 1w. The horizontal field of view of the dot matrix transmitting unit 20 is 135°, and the vertical field of view is 12°~60°.

[0055] See also Figure 5 The depth camera 100 further includes a substrate 50 and a bottom plate 60. The substrate 50 is disposed on one side of the bottom plate 60, the dot matrix emitting unit 20 and the receiving unit 40 are disposed on the side of the substrate 50 away from the bottom plate 60, and the line laser emitting unit 10 includes two line laser emitting modules 11, which are disposed on the bottom plate 60 and located on opposite sides of the substrate 50, wherein the two line laser emitting modules 11, the dot matrix emitting unit 20 and the receiving unit 40 are disposed side by side. In this way, the space utilization rate can be improved, the cost is low, and the appearance is more beautiful.

[0056] Specifically, when each line laser emission module 11 irradiates into space at an inclination angle of 20°~50° toward the receiving unit 40, the minimum ground blind area is 0.06m. The emission wavelength range of the line laser emission module 11 is 850nm~1200nm, and 940±15nm is preferred. The optical power of the line laser emission module 11 is less than 1w. The horizontal field of view angle of the line laser emission module 11 is 1°~2°, and the vertical field of view angle is 60°.

[0057] In some embodiments, see Figure 6 , the depth camera 100 also includes a substrate 50 and a bottom plate 60. The substrate 50 is arranged on one side of the bottom plate 60, the dot matrix emitting unit 20 and the receiving unit 40 are arranged on the side of the substrate 50 away from the bottom plate 60, and the line laser emitting unit 10 includes two line laser emitting modules 11, and the two line laser emitting modules 11 are arranged on the bottom plate 60 and are located on opposite sides of the substrate 50, wherein the two line laser emitting modules 11 and the substrate 50 are arranged side by side in the horizontal direction, and the dot matrix emitting unit 20 and the receiving unit 40 are arranged side by side in the vertical direction. In this way, the space utilization rate can be improved, the cost is low, and the appearance is more beautiful. The value range of the distance between each line laser emitting module 11 and the receiving unit 40 is 0.05m~0.15m.

[0058] See also Figure 7 The dot matrix light sources 21 are arranged in multiple rows, wherein the dot matrix light sources 21 in every three rows are arranged in a staggered and cyclic manner. In this way, the interval blind area between two adjacent dot matrix light sources 21 in each row of dot matrix light sources 21 can be supplemented by the dot matrix light sources 21 in the next row, thereby making the resolution of the depth camera 100 higher.

[0059] In a possible implementation, the line laser emitting unit 10 and the dot matrix emitting unit 20 are alternately lit up in time-sharing to alternately project a uniform light pattern and a speckle pattern. The receiving unit 40 is electrically connected to the line laser emitting unit 10 and the dot matrix emitting unit 20, and controls the line laser emitting unit 10 and the dot matrix emitting unit 20 to alternately illuminate.

[0060] In the solution provided by the embodiment of the present application, by alternately lighting up the line laser emitting unit 10 and the dot matrix emitting unit 20, mutual interference when the two light beams are irradiated at the same time can be avoided, ensuring that each light beam can be independently projected and received, thereby improving the accuracy and reliability of the measurement. If the two light beams are projected at the same time, they may overlap and interfere with each other in the space to be measured, making it difficult for the receiving unit 40 to distinguish and accurately measure the light signal of each light beam. Alternating projection can avoid such interference and ensure that the measurement data of each light beam is independent and accurate.

[0061] In a possible embodiment, the photosensitive chip 41 can be an I-TOF chip, and the line laser receiving area 411 is used to obtain the first depth image corresponding to when the multiple line laser beams 101 are turned on and off through the principle of triangulation, and is used to obtain the second depth image corresponding to the multiple line laser beams 101 through the principle of TOF ranging; and obtain obstacle avoidance depth information based on the fused first depth image and the second depth image; the dot matrix light beam 201 emitted by the dot matrix emitting unit 20 includes at least two different frequencies, and at least two different frequencies are first short-exposed in sequence and then long-exposed in sequence, and the dot matrix receiving area 412 is used to obtain a third depth image during short exposure and a fourth depth image during long exposure, and obtain navigation depth information based on the third depth image and the fourth depth image.

[0062] In the solution provided in the embodiment of the present application, by acquiring the first depth image corresponding to when multiple line laser beams 101 are turned on and off, and acquiring the second depth image corresponding to multiple line laser beams 101 through the ITOF ranging principle, the interference of background noise and ambient light can be effectively eliminated, and the accuracy of obstacle avoidance depth information can be improved. During short exposure, the depth image captured by the dot matrix receiving area 412 mainly contains the details of the high-brightness area, which is suitable for processing surfaces with high reflectivity. During long exposure, the depth image captured by the dot matrix receiving area 412 mainly contains the details of the low-brightness area, which is suitable for processing surfaces with low reflectivity. By acquiring short-exposure and long-exposure depth images of different frequencies of the dot matrix transmitting unit 20, the dynamic range and signal-to-noise ratio problems can be effectively handled, and the reliability of navigation depth information can be improved.

[0063] In this embodiment, the lighting time of each line laser beam 101 in the multiple line laser beams 101 for obtaining the corresponding first depth image through the triangulation ranging principle is 2 phases, and the off time is also 2 phases; the time of each line laser beam 101 in the multiple line laser beams 101 for obtaining the corresponding second depth image through the ITOF ranging principle is 4 phases.

[0064] In a possible implementation, at least two different frequencies may perform long exposure first and then short exposure in sequence, and the dot matrix receiving area 412 is used to obtain depth images during long exposure and short exposure and calculate the navigation depth information; or at least two different frequencies may perform short exposure, long exposure, long exposure and short exposure in sequence; or at least two different frequencies may perform short exposure, long exposure, short exposure and short exposure in sequence; or at least two different frequencies may perform long exposure, short exposure, short exposure and short exposure in sequence; but not limited to this.

[0065] In a possible implementation, the at least two different frequencies include a first frequency and a second frequency, the first frequency is greater than the second frequency, and a transmission sequence of the first frequency takes precedence over a transmission sequence of the second frequency.

[0066] In the solution provided in the embodiment of the present application, by preferentially transmitting the first frequency and then transmitting the second frequency, the data corresponding to the first frequency can be used when performing depth calculation, and the data corresponding to the second frequency can be used for period expansion, thereby ensuring the real-time nature of the depth data.

[0067] In this embodiment, at least two different frequencies are two frequencies, which can avoid the super-period problem and realize long-distance ranging. The two frequencies can be selected from 1MHZ-100MHZ. For example, a 37.65MHZ / 45.18MHZ frequency combination can be selected to achieve a detection distance of 20m, a 60.24MHZ / 48.192MHZ frequency combination can be selected to achieve a detection distance of 12.5m, and a 60.24MHZ / 52.71MHZ frequency combination can be selected to achieve a detection distance of 20m.

[0068] In this embodiment, the short exposure time of each frequency is 4 phases, and the long exposure time of each frequency is 4 phases.

[0069] In this embodiment, when the line laser emitting unit 10 includes two line laser emitting modules, the two line laser emitting modules light up one phase in sequence.

[0070] In a possible implementation, the photosensitive chip 41 may be a D-TOF chip, the dot matrix transmitting unit 20 includes a plurality of dot matrix transmitting areas (not shown), the plurality of dot matrix transmitting areas are sequentially lit up and have the same transmitting frequency, the line laser receiving area 411 is used to collect the light signal corresponding to the line laser beam 101 to obtain obstacle avoidance depth information, and the dot matrix receiving area 412 is used to sequentially collect the light signal corresponding to the dot matrix transmitting area to obtain navigation depth information. It can be understood that the obstacle avoidance depth information and the navigation depth information can be output at one time.

[0071] In the solution provided in the embodiment of the present application, the dot matrix transmitting unit 20 can be divided into one dot matrix transmitting area or divided into multiple dot matrix transmitting areas. The multiple dot matrix transmitting areas can be illuminated at one time or in sequence. The time-sharing transmission method in which the multiple dot matrix transmitting areas are illuminated in sequence can ensure that the light beams of each dot matrix transmitting area are independently projected and received, avoiding light beam overlap and interference caused by simultaneous transmission; the dot matrix receiving area 412 of the receiving unit 40 collects the light signals corresponding to each dot matrix transmitting area in sequence, and can generate a high-density depth map, which can improve the accuracy and resolution of navigation depth information.

[0072] In this embodiment, the frequency of the dot matrix transmitting unit 20 can be selected from 1 MHZ to 10 MHZ, for example, 5 MHZ can be selected to achieve a detection distance of 30 m.

[0073] In one possible implementation, when the line laser emitting unit 10 is turned on, only the corresponding line laser receiving area 411 in the photosensitive surface 410 of the receiving unit 40 works and outputs, thereby reducing the amount of data and processing time; when the dot matrix emitting unit 20 is turned on, both the line laser receiving area 411 and the dot matrix receiving area 412 in the photosensitive surface 410 of the receiving unit 40 work and output, thereby improving the accuracy and reliability of the overall measurement.

[0074] In a possible implementation, the function of the optical element 30 is to perform spatial light modulation on each incident light beam, that is, to split and replicate each light beam to form a speckle pattern or a uniform light pattern. The optical element 30 can be a DOE or a super lens. In some embodiments, there is one optical element 30, and one optical element 30 is arranged in the light-emitting path of the line laser emitting unit 10 and the dot matrix emitting unit 20. In some embodiments, there are two optical elements 30, one of which is a DOE and the other is a super lens, the DOE is arranged in the light-emitting path of the line laser emitting unit 10, and the super lens is arranged in the light-emitting path of the dot matrix emitting unit 20.

[0075] Among them, the obstacle avoidance strategy of the mobile robot 1000 is: when the vertical field of view of the dot matrix transmitting unit 20 is less than 30°, its blind area is larger than that of the line laser transmitting unit 10. At this time, the dot matrix transmitting unit 20 can be preset to judge obstacle avoidance, and the mobile robot 1000 can be decelerated after the obstacle is found, and then the line laser transmitting unit 10 with a smaller blind area can accurately avoid the obstacle to achieve perfect obstacle avoidance; if the vertical field of view of the dot matrix transmitting unit 20 is greater than or equal to 30°, its blind area is smaller than that of the line laser transmitting unit 10. At this time, the line laser transmitting unit 10 judges obstacle avoidance, and the dot matrix transmitting unit 20 obtains the three-dimensional information of the obstacle. The depth information of the point-line overlap position can complement each other, thereby completing accurate obstacle avoidance. In addition, the dot matrix transmitting unit 20 for spatial height measurement presets a scheme for judging obstacle avoidance, and its vertical field of view angle direction is set to a field of view range of 12°~60°, which can timely discover some low objects and determine whether they can enter.

[0076] The present application also provides a method for obtaining depth information, comprising the steps of: S10, sequentially emitting a plurality of line laser beams 101 of preset width and at least two rows of staggered dot beams 201, wherein the plurality of line laser beams 101 are vertical and arranged at an angle in the projection area, the line laser beams 101 pass through an optical element to project a uniform light pattern toward the space to be measured, and the dot beams 201 pass through the optical element to project a speckle pattern toward the space to be measured; S20, receiving a light signal corresponding to the uniform light pattern and a light signal corresponding to the speckle pattern returned from the space to be measured; S30, obtaining obstacle avoidance depth information according to the light signal corresponding to the uniform light pattern; and obtaining navigation depth information according to the light signal corresponding to the speckle pattern.

[0077] In the depth information acquisition method provided in the embodiment of the present application, a plurality of linear laser beams 101 with a preset width and an angle are first emitted in the horizontal direction, and the linear laser beams 101 pass through the optical element to project a uniform light pattern toward the space to be measured, and then the obstacle avoidance depth information is obtained according to the light signal corresponding to the uniform light pattern, so that more complete obstacle contour information can be obtained, and high-precision obstacle avoidance can be achieved in the near distance, and the problems of close-range blind spots, multi-paths, black material recognition, and small object recognition can be solved, and at the same time, the high-precision characteristics are provided; then at least two rows of staggered dot matrix beams 201 are emitted in the horizontal direction, and the dot matrix beams 201 pass through the optical element to project a speckle pattern toward the space to be measured, and then Navigation depth information is obtained based on the light signal corresponding to the speckle pattern, so as to identify the height of the object in the measured space for stereoscopic height measurement and stereo positioning navigation. The problem of stereoscopic height measurement and identification of low objects can be solved. By staggering at least two rows of dot matrix light sources in the multiple rows of dot matrix light sources included in the dot matrix emitting unit, the interval blind area between two adjacent dot matrix light sources in each row of dot matrix light sources can be supplemented by the dot matrix light sources in the next row, so that the resolution of the depth camera is higher. Therefore, by cooperating with the emission line laser beam 101 and the emission dot matrix beam 201, the existing problem of not being able to simultaneously realize stereo positioning navigation and close-range high-precision obstacle avoidance can be solved.

[0078] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claim involved. In addition, it is obvious that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural.

[0079] Finally, it should be noted that the above implementation modes are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred implementation modes, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A depth camera, characterized in that: include: A line laser emitting unit, used to emit a plurality of line laser beams of preset width, wherein the plurality of line laser beams do not intersect in a projection area and have an angle with the vertical direction of less than 30 degrees, and at least one of the line laser beams has an angle with the vertical direction of greater than 0 degrees in the projection area; A dot matrix emitting unit is disposed on the side of the line laser emitting unit and is used to emit a dot matrix light beam. The dot matrix emitting unit includes a plurality of rows of dot matrix light sources, and at least two rows of the dot matrix light sources are regularly staggered and cyclically arranged. An optical element is arranged in the light emitting paths of the line laser emitting unit and the dot matrix emitting unit, the line laser beam passes through the optical element to project a uniform light pattern toward the space to be measured, and the dot matrix beam passes through the optical element to project a speckle pattern toward the space to be measured, the uniform light pattern and the speckle pattern are both projected into an obstacle avoidance area for obstacle avoidance, and the speckle pattern is projected into a navigation area for navigation; A receiving unit is arranged on the side of the line laser emitting unit and the dot matrix emitting unit, and is used to receive light signals corresponding to the uniform light pattern and the speckle pattern to obtain short-range obstacle avoidance depth information, thereby performing stereo height measurement and short-range obstacle avoidance, and is used to receive light signals corresponding to the speckle pattern to obtain navigation depth information, thereby performing stereo positioning navigation.

2. The depth camera according to claim 1, characterized in that When the multiple line laser beams are projected into the space to be measured, the height information of the obstacles in the space to be measured can be obtained. When the dot matrix beams are projected into the space to be measured, the contour information of the obstacles in the space to be measured can be obtained. The receiving unit receives the light signals corresponding to the height information and the contour information to perform stereo height measurement.

3. The depth camera according to claim 1, characterized in that The depth camera also includes a substrate and a bottom plate, the substrate is arranged on one side of the bottom plate, the dot matrix emitting unit and the receiving unit are arranged on the side of the substrate away from the bottom plate, and the line laser emitting unit includes two line laser emitting modules, the two line laser emitting modules are arranged on the bottom plate and located on opposite sides of the substrate, wherein the two line laser emitting modules, the dot matrix emitting unit and the receiving unit are arranged side by side.

4. The depth camera according to claim 1, characterized in that The depth camera also includes a substrate and a bottom plate, the substrate is arranged on one side of the bottom plate, the dot matrix emitting unit and the receiving unit are arranged on the side of the substrate away from the bottom plate, and the line laser emitting unit includes two line laser emitting modules, the two line laser emitting modules are arranged on the bottom plate and located on opposite sides of the substrate, wherein the two line laser emitting modules and the substrate are arranged side by side in the horizontal direction, and the dot matrix emitting unit and the receiving unit are arranged side by side in the vertical direction.

5. The depth camera according to claim 1, characterized in that: The line laser emitting unit and the dot matrix emitting unit are alternately lit up in time-sharing to alternately project the uniform light pattern and the speckle pattern.

6. The depth camera according to claim 1, characterized in that: The photosensitive surface of the receiving unit includes a line laser receiving area and a dot matrix receiving area, the line laser receiving area is used to obtain a first depth image corresponding to when a plurality of line laser beams are turned on and off by a triangulation ranging principle, and is used to obtain a second depth image corresponding to a plurality of line laser beams by a TOF ranging principle, and obtain the obstacle avoidance depth information according to the fused first depth image and the second depth image; The dot matrix light beam emitted by the dot matrix transmitting unit includes at least two different frequencies, and the at least two different frequencies are first subjected to short exposure and then to long exposure in sequence. The dot matrix receiving area is used to obtain a third depth image during the short exposure and a fourth depth image during the long exposure, and the navigation depth information is obtained according to the third depth image and the fourth depth image.

7. The depth camera according to claim 6, characterized in that: The at least two different frequencies include a first frequency and a second frequency, the first frequency is greater than the second frequency and a transmission order of the first frequency takes precedence over a transmission order of the second frequency.

8. The depth camera according to claim 1, characterized in that: The dot matrix transmitting unit includes one or more dot matrix transmitting areas, and multiple dot matrix transmitting areas can be lit up at one time or in sequence. The photosensitive surface of the receiving unit includes a line laser receiving area and a dot matrix receiving area. The line laser receiving area is used to collect light signals corresponding to the line laser light beam to obtain obstacle avoidance depth information, and the dot matrix receiving area is used to collect light signals corresponding to the dot matrix transmitting area to obtain navigation depth information.

9. The depth camera according to claim 8, characterized in that: When the line laser emitting unit is turned on, only the corresponding line laser receiving area in the photosensitive surface of the receiving unit works and outputs; when the dot matrix emitting unit is turned on, both the line laser receiving area and the dot matrix receiving area in the photosensitive surface of the receiving unit work and output.

10. A mobile robot, characterized in that: include: Robot body; and The depth camera according to any one of claims 1 to 9, wherein the depth camera is mounted on the robot body.

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