3D camera

Abstract

This application relates to the field of three-dimensional imaging technology and proposes a 3D camera with temperature drift control. It mainly comprises a housing (100), a 3D lens assembly (104), a heating plate (106), and a heating controller. The 3D lens assembly (104) is fixedly mounted on the lower cover plate (103) of the housing (100) via a base fixing member (105). The heating plate (106) is fixed on the lower cover plate (103) and located between the base fixing member (105) and the lower cover plate (103). The heating plate (106) is fixedly installed inside the housing (100) and electrically connected to the heating controller. This application can heat the 3D camera using the heating plate, which can quickly increase the temperature of the core components and cavity inside the camera, allowing the 3D camera temperature to quickly reach a stable state after power-on, effectively reducing the camera's temperature drift stabilization time.

Description

Technical Field

[0001] This application relates to the field of three-dimensional imaging technology and proposes a 3D camera with temperature drift control. Background Technology

[0002] As a core breakthrough in the field of machine vision, 3D imaging technology has been widely applied in key areas such as industrial precision inspection, autonomous driving environmental perception, medical imaging diagnosis, and consumer electronics interaction.

[0003] 3D cameras, as optical devices for 3D imaging, are the hardware foundation of 3D imaging technology and play a decisive role in imaging accuracy. A major category of 3D cameras is based on the principle of binocular vision. In this type of camera, an object is typically observed from two perspectives, and the parallax between the two perspectives is calculated. Depth information is determined through the parallax relationship. This category includes structured light cameras and binocular cameras. In 3D cameras that calculate depth through parallax, the relative position between the two perspectives is defined as the camera's baseline. The camera baseline distance can be obtained through calibration and is used as important known information in 3D reconstruction. The 3D camera baseline directly affects the reconstructed depth, and the accuracy of the baseline information directly affects the reconstruction accuracy.

[0004] 3D cameras involve a large amount of data generation and processing, and heat generation is inevitable during use. The heat generated after the camera is turned on raises the temperature of the camera mechanism, causing thermal deformation. This results in a change in the 3D camera's baseline with the camera's temperature, leading to instability in the 3D camera's measurement results. The change in camera measurement results caused by structural temperature variations is called temperature drift.

[0005] Taking structured light 3D cameras as an example, these cameras provide two perspectives, one from an optical engine (projector) and the other from a camera (2D). During use, the light source of the optical engine, the projection chip, and the camera control circuitry all generate heat. However, as the integration of structured light 3D cameras increases, more computing and control units are integrated inside to achieve real-time depth calculations. These computing units also generate a significant amount of heat. This heat causes the structured light camera to experience temperature fluctuations of tens of degrees Celsius from power-on to a stable temperature state, and these temperature changes can take tens of minutes or even hours to reach a stable state.

[0006] For example Figure 1 As shown, Figure 1 This is a graph showing the temperature drift change of the striped structured light 3D camera system after it is powered on. Figure 1 The vertical axis represents the drift of the target captured by the 3D camera, and the horizontal and vertical axes represent the time values ​​of the target's displacement recorded after the camera was turned on. Figure 1The experimental results show that the temperature drift curve of a typical 3D camera resembles an exponential decay curve. The temperature drift changes rapidly for a period of time after the 3D camera is turned on, then gradually slows down and reaches a stable state. However, this stabilization process is very slow; the entire system only reaches basic stability after 100 minutes of operation, and even reaching 90% of the maximum temperature drift takes approximately 55 minutes. If using existing 3D cameras for measurements, to obtain results within 10% error, the system needs at least 55 minutes of warm-up after startup.

[0007] Therefore, temperature drift causes the measurement results of a 3D camera to change over time after it is turned on, resulting in inaccurate results for a period of time after power-on. Temperature drift lasting for tens of minutes or even hours can limit the usability of a 3D camera. Therefore, reducing the temperature drift stabilization time of the optical engine is of great significance for the use of 3D cameras. Summary of the Invention

[0008] To overcome at least one problem or deficiency in the prior art, this application proposes a 3D camera.

[0009] The 3D camera proposed in this application includes a housing and a 3D lens assembly. The 3D lens assembly is fixedly mounted on the lower cover plate of the housing via a base fixing member. The 3D camera also includes a heating plate and a heating controller. The heating plate is fixed on the lower cover plate and located between the base fixing member and the lower cover plate. The heating plate is fixedly mounted inside the housing and electrically connected to the heating controller.

[0010] Based on the above embodiments, the heating plate of this application further includes a heating substrate and a first protrusion. One side of the heating substrate is fixedly connected to the lower cover plate, and the other side of the heating substrate is fixedly connected to the first protrusion. The first protrusion is used to abut against the base fixing member. When the heating plate is fixed between the base fixing member and the lower cover plate, the side wall of the first protrusion is in close contact with the base fixing member.

[0011] Based on the above embodiments, the heating substrate of this application is further provided with a heating coil, and the first boss is provided with a heating power interface electrically connected to the heating coil, and the heating power interface is electrically connected to the heating controller.

[0012] Based on the above embodiments, the longitudinal section of the heating substrate in this application is circular or polygonal, and the bottom surface of the base fixing member is provided with a groove that matches the longitudinal section of the heating substrate for accommodating the heating substrate.

[0013] Based on the above embodiments, the longitudinal section of the heating substrate of this application is circular or polygonal. The lower cover plate is provided with a second protrusion that matches the base fixing member for fixed connection with the base fixing member. The second protrusion has a groove that matches the longitudinal section of the heating substrate for accommodating the heating substrate.

[0014] Based on the above embodiments, the longitudinal section of the first boss in this application further includes an L-shaped platform, the short side and the long side of the L-shaped platform are in close contact with the base fixing member, and a cavity is formed between the heating substrate and the bottom surface of the base fixing member.

[0015] Based on the above embodiments, the 3D camera of this application further includes a first temperature sensor electrically connected to the heating controller; the first temperature sensor is fixedly installed inside the housing and electrically connected to the heating controller.

[0016] Based on the above embodiments, the 3D camera of this application further includes a second temperature sensor electrically connected to the heating controller; the first temperature sensor is disposed near the 3D lens assembly; the second temperature sensor is disposed away from the 3D lens assembly relative to the first temperature sensor.

[0017] Based on the above embodiments, the 3D camera of this application further includes a heat conduction bracket; one end of the heat conduction bracket is fixed to the base fixing member, the other end of the bracket is fixed to the upper side of the 3D lens assembly, and the lower side of the 3D lens assembly is fixed to the base fixing member.

[0018] Based on the above embodiments, the housing of this application further includes a fixedly connected upper cover plate, a middle frame plate, and a lower cover plate; the 3D lens assembly includes an electrically connected camera lens and a camera PCB board; the lower cover plate is a heating base plate, and the heating plate is fixedly disposed on the inner side of the lower cover plate; the upper cover plate is a heat dissipation base plate, the camera PCB board is fixedly disposed on the inner side of the upper cover plate, and heat dissipation fins are disposed on the outer side of the upper cover plate.

[0019] In summary, due to the adoption of the above technical solutions, the beneficial effects created by the present invention include: the 3D camera proposed in this application is equipped with a heating plate, which can heat the base fixing component and the lower cover plate. It can also heat the 3D lens assembly installed on it through the base fixing component, and at the same time, it can heat the 3D camera cavity through the lower cover plate. This can quickly increase the temperature of the core components and cavity inside the camera, so that the temperature of the 3D camera can quickly reach a stable state after power-on, effectively reducing the temperature drift stabilization time of the camera.

[0020] It should be noted that different embodiments of this application may produce different beneficial effects. In different embodiments, the beneficial effects that may be produced may be any one or more combinations mentioned in this application, or any other beneficial effects that may be obtained that are not exhaustively described. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are merely some examples or embodiments of this application. For those skilled in the art, without creative effort, the solutions shown in these drawings can be replaced, adjusted, combined, etc., to create different technical solutions; and this application can also be applied to other similar scenarios based on these drawings to obtain application solutions for other scenarios.

[0022] in:

[0023] Figure 1 Temperature drift curves of an existing 3D camera system after power-on.

[0024] Figure 2 External structure diagram of a 3D camera shown according to some embodiments of this application;

[0025] Figure 3 Internal structure diagram of a 3D camera shown according to some embodiments of this application;

[0026] Figure 4 Structural diagram of the lower cover plate of a 3D camera shown according to some embodiments of this application;

[0027] Figure 5 Structural diagram of the lower cover plate of a 3D camera shown according to some embodiments of this application;

[0028] Figure 6 A cross-sectional view of the lower cover plate of a 3D camera shown according to some embodiments of this application;

[0029] Figure 7 Internal structure diagram of a 3D camera shown according to some embodiments of this application;

[0030] Figure 8 The temperature drift curve of the 3D camera system after power-on is shown in this application.

[0031] In the diagram: 100-Housing, 101-Upper cover, 102-Middle frame, 103-Lower cover, 104-3D lens assembly, 105-Base fixture, 106-Heating plate, 107-Heating substrate, 108-First boss, 109-Second boss, 110-Cavity, 111-Heat conduction bracket, 112-Heat sink, 113-External interface assembly, 114-Heating controller, 115-2D camera, 116-Projection PCB board, 117-Image processing FPGA board, 118-Projector.

[0032] It should be noted that identical reference numerals in the figures represent the same structure or operation. Similar reference numerals and letters in the figures of this application indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Because this application has numerous figures and reference numerals, if there are discrepancies between the descriptions of the figures and the illustrations in the specification, those skilled in the art should understand them based on the logical coherence of the technical principles described in this application. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and it is not possible to exhaustively describe all embodiments.

[0034] To address the temperature drift issue in 3D cameras, reduce temperature drift time, and quickly bring 3D cameras to a stable operating state, this application designs various 3D cameras with temperature drift control, combining space optimization design with effective temperature drift control for compact 3D cameras. The core working principle involves adding a heating plate between the 3D lens assembly and the lower cover of the camera housing. This heating plate heats the bottom of the 3D lens assembly and the lower cover of the housing. Heat is directly conducted to the core components of the 3D lens assembly through its bottom, and then transferred to the camera housing and diffused throughout the entire internal cavity of the 3D camera via the lower cover. This rapidly and effectively increases the temperature of the core components of the 3D camera, reducing temperature drift time.

[0035] Under normal circumstances, such as Figure 2As shown, the 3D camera mainly consists of a housing 100, a 3D lens assembly 104, and an external interface assembly 113. The 3D lens assembly 104 includes an electrically connected camera lens and a camera PCB board. The 3D camera can be a structured light 3D camera, a binocular stereo camera, etc. Taking a structured light 3D camera as an example, the camera lens includes a 2D camera 115 and a projector 118. The camera PCB board includes a projector PCB board 116 and an image processing FPGA board 117. The external I / O interface of the image processing FPGA board 117 is electrically connected to the external interface assembly 113. The image processing FPGA board 117 is also electrically connected to the 2D camera 115 and the projector 118 through the projector PCB board 116. Under normal circumstances, when starting up, the lens, projector, projector PCB board, image processing FPGA board, and other components in the 3D camera will generate a large temperature difference. Therefore, this application proposes to actively increase the temperature of the relevant components inside the 3D camera by adding a heating plate 106.

[0036] Example 1

[0037] like Figure 2-7 As shown, the 3D camera proposed in this application also includes a heating plate 106 and a heating controller; the heating plate 106 is fixedly installed inside the housing 100 and electrically connected to the heating controller; the 3D lens assembly 104 of the 3D camera is fixedly installed on the lower cover plate 103 of the housing 100 via a base fixing member 105, and the heating plate 106 is fixed on the lower cover plate 103 and located between the base fixing member 105 and the lower cover plate 103. The heating controller is used to determine whether to control the heating plate 106 to heat. This embodiment proposes a simple controller design, where the heating controller can be a timer, configured to connect the power supply to the heating plate 106 and start timing when the 3D camera is powered on, and disconnect the power supply to the heating plate 106 to stop heating when the heating time reaches a preset time threshold.

[0038] In some cases, such as Figure 4-6As shown, the heating plate 106 can be mainly composed of a heating base plate 107 and a first protrusion 108. A heating coil can be provided in the heating base plate 107 for heating. The first protrusion 108 is provided with a heating power interface electrically connected to the heating coil, and the heating power interface is electrically connected to the heating controller. One side of the heating base plate 107 is fixedly connected to the lower cover plate 103, and the other side of the heating base plate 107 is fixedly connected to the first protrusion 108. The first protrusion 108 is used to abut against the base fixing member 105. When the heating plate 106 is fixed between the base fixing member 105 and the lower cover plate 103, the sidewall of the first protrusion 108 is in close contact with the base fixing member 105. The first boss 108 can serve as a power interface component for the heating plate 106, a limiting component for fixing the base fixing member 105, and a heat conduction component to conduct the heat of the heating plate 106 to the 3D lens assembly 104 through the base fixing member 105.

[0039] The base fixing member 105 described in this application has a groove on its bottom surface that matches the longitudinal section of the heating substrate 107, for accommodating the heating substrate 107. In a simple design, the groove and the longitudinal section of the heating substrate 107 can be circular or polygonal.

[0040] In some embodiments, the lower cover plate 103 may be provided with a second protrusion 109 that matches the base fixing member 105 for fixed connection with the base fixing member 105. The second protrusion 109 has a groove that matches the longitudinal section of the heating substrate 107 for accommodating the heating substrate 107. In some embodiments, the bottom of the base fixing member 105 may be planar and attached to the second protrusion 109 for fixed connection. In some embodiments, the bottom of the base fixing member 105 may also have a groove that matches the longitudinal section of the heating substrate 107. The heating substrate 107 is simultaneously installed in the groove of the second protrusion 109 and the groove at the bottom of the base fixing member 105.

[0041] For better heat conduction or fixed positioning, in some embodiments, such as Figure 6 As shown, the longitudinal section of the first boss 108 may include an L-shaped platform. The short and long sides of the L-shaped platform are in contact with the base fixing member 105, and a cavity 110 is formed between the heating substrate 107 and the bottom surface of the base fixing member 105.

[0042] In some embodiments, the housing 100 includes a fixedly connected upper cover plate 101, a middle frame plate 102, and a lower cover plate 103; the 3D lens assembly 104 includes an electrically connected camera lens and a camera PCB board; the lower cover plate 103 is a heating base plate, and the heating plate 106 is fixedly disposed on the inner side of the lower cover plate 103; the upper cover plate 101 is a heat dissipation base plate, the camera PCB board is fixedly disposed on the inner side of the upper cover plate 101, and a heat sink 112 is disposed on the outer side of the upper cover plate 101. The projector PCB board is fixed on the inner side of the upper cover plate 101, the image processing FPGA board is fixed on one side of the middle frame plate 102, and the field of view of the camera lens is located on the other side of the middle frame plate 102.

[0043] Example 2

[0044] This application can be further designed to achieve a more accurate temperature drift control method by adding a temperature sensor, i.e., a single temperature sensor monitoring scheme.

[0045] In some embodiments, the 3D camera may further include a first temperature sensor; the first temperature sensor is fixedly installed inside the housing and electrically connected to the heating controller. Specifically, the installation location may be near the heat source of the 3D lens assembly 104, or it may be fixedly installed on the inner wall of the housing. The heating controller may be a comparator, configured to connect the power supply to the heating plate 106 when the 3D camera is powered on, and to collect temperature information through the first temperature sensor. When the temperature information reaches a first preset temperature threshold, the power supply to the heating plate 106 is disconnected to stop heating. The heating controller may also be configured to connect the power supply to the heating plate 106 to start heating when the temperature information is less than a second preset temperature threshold, and to disconnect the power supply to the heating plate 106 to stop heating when the temperature information is greater than a third preset temperature threshold.

[0046] Example 3

[0047] This application can be further designed to achieve a more accurate temperature drift control method by adding multiple temperature sensors, i.e., a multi-temperature sensor monitoring scheme.

[0048] In some embodiments, the 3D camera described in this application may further include a first temperature sensor and a second temperature sensor electrically connected to the heating controller; the first temperature sensor may be disposed near the heat source of the 3D lens assembly 104 to monitor the temperature near the heat source; the second temperature sensor may be disposed away from the 3D lens assembly 104 relative to the first temperature sensor to monitor the temperature at the heat source location or the room temperature of the 3D camera. The heating controller may be a comparator configured to turn on the power to the heating plate 106 to start heating when the temperature difference collected by the first temperature sensor and the second temperature sensor is less than a fourth preset temperature threshold, and to turn off the power to the heating plate 106 to stop heating when the temperature difference is greater than a fifth preset temperature threshold.

[0049] In some embodiments, the timer can be combined with a comparator monitored by a single temperature sensor or a comparator monitored by multiple temperature sensors to compare temperatures to determine whether heating is needed. At the same time, the control logic of the timer can be combined to increase the reliability of system control and ensure the effectiveness of reducing temperature drift stabilization time.

[0050] To enhance the effectiveness of heat conduction in the heating plate, a heat conduction bracket 111 may be added in some embodiments. One end of the heat conduction bracket 111 is fixed to the base fixing member 105, and the other end is fixed to the upper side of the 3D lens assembly 104. The lower side of the 3D lens assembly 104 is fixed to the base fixing member 105. The heat conduction bracket 111 can quickly conduct the temperature of the base fixing member 105 to the upper side of the 3D lens assembly 104, for example, to heat the projector in a 3D camera or to heat the projection PCB board.

[0051] The temperature drift curve of the 3D camera measured after temperature control is as follows: Figure 8 As shown, the temperature drift of the system structure quickly reaches equilibrium within 15 minutes of power-on, reducing the temperature drift time by 70%. This result proves that the design and control scheme proposed in this application greatly compresses the temperature drift time of the 3D camera.

[0052] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0053] Furthermore, this application uses specific terms to describe its embodiments. For example, "one embodiment" or "some embodiments" refers to a particular feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "some embodiments" or "one embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0054] As indicated in this application and claims, unless the context clearly indicates otherwise, the terms "a," "first," "second," and / or "the" are not specifically singular in quantity, but rather descriptive terms used for distinction and classification. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0055] The above descriptions are merely various embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A 3D camera, including a housing (100) and a 3D lens assembly (104), the 3D lens assembly (104) being fixedly mounted on the lower cover plate (103) of the housing (100) by a base fastener (105); Its features are: The 3D camera also includes a heating plate (106) and a heating controller; The heating plate (106) is fixed on the lower cover plate (103) and located between the base fixing member (105) and the lower cover plate (103); The heating plate (106) is fixedly installed inside the housing (100) and electrically connected to the heating controller.

2. The 3D camera according to claim 1, characterized in that: The heating plate (106) includes a heating substrate (107) and a first boss (108). One side of the heating substrate (107) is fixedly connected to the lower cover plate (103), and the other side of the heating substrate (107) is fixedly connected to the first boss (108). The first boss (108) is used to abut against the base fixing member (105). When the heating plate (106) is fixed between the base fixing member (105) and the lower cover plate (103), the side wall of the first boss (108) is in close contact with the base fixing member (105).

3. The 3D camera according to claim 2, characterized in that: A heating coil is provided inside the heating substrate (107), and a heating power interface electrically connected to the heating coil is provided inside the first boss (108). The heating power interface is electrically connected to the heating controller.

4. The 3D camera according to claim 2, characterized in that: The longitudinal section of the heating substrate (107) is circular or polygonal, and the bottom surface of the base fixing member (105) is provided with a groove that matches the longitudinal section of the heating substrate (107) for accommodating the heating substrate (107).

5. The 3D camera according to claim 2, characterized in that: The longitudinal section of the heating substrate (107) is circular or polygonal. The lower cover plate (103) is provided with a second boss (109) that matches the base fixing member (105) for fixed connection with the base fixing member (105). The second boss (109) has a groove that matches the longitudinal section of the heating substrate (107) for accommodating the heating substrate (107).

6. The 3D camera according to claim 2, characterized in that: The longitudinal section of the first boss (108) includes an L-shaped platform. The short and long sides of the L-shaped platform are in contact with the base fixing member (105), and a cavity (110) is formed between the heating substrate (107) and the bottom surface of the base fixing member (105).

7. The 3D camera according to claim 1, characterized in that: The 3D camera also includes a first temperature sensor; The first temperature sensor is fixedly installed inside the housing and electrically connected to the heating controller.

8. The 3D camera according to claim 1, characterized in that: The 3D camera also includes a first temperature sensor and a second temperature sensor electrically connected to the heating controller; The first temperature sensor is located near the 3D lens assembly (104); the second temperature sensor is located away from the 3D lens assembly (104) relative to the first temperature sensor.

9. The 3D camera according to claim 1, characterized in that: The 3D camera also includes a heat conduction bracket (111); one end of the heat conduction bracket (111) is fixed to the base fixing member (105), and the other end is fixed to the upper side of the 3D lens assembly (104), and the lower side of the 3D lens assembly (104) is fixed to the base fixing member (105).

10. The 3D camera according to claim 1, characterized in that: The housing (100) includes an upper cover plate (101), a middle frame plate (102), and a lower cover plate (103) that are fixedly connected. The 3D lens assembly (104) includes an electrically connected camera lens and a camera PCB board; The lower cover plate (103) is a heating base plate, and the heating plate (106) is fixedly disposed on the inner side of the lower cover plate (103); The upper cover plate (101) is a heat dissipation base plate. The camera PCB board is fixedly disposed on the inner side of the upper cover plate (101). A heat sink (112) is disposed on the outer side of the upper cover plate (101).

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