Optical communication device, optical communication method, and laser radar

Abstract

The application relates to the technical field of optical communication, and provides an optical communication device, a laser radar and an optical communication method. The optical communication device comprises a first controller, a first light-emitting device installed on a rotating part, a first light-sensing device, a comparator and a second controller installed on a fixed part, realizes a positive communication connection from the rotating part to the fixed part, light emitted by the first light-emitting device is transmitted through an optical channel and is close to or coincides with a rotating axis, the pulse width of the first light signal is small, the first light-emitting device also emits a preset light signal containing a preset pulse width, the preset light signal is converted into a preset pulse signal through the first light-sensing device and the comparator, the second controller measures a measurement pulse width of the preset pulse signal and compares the measurement pulse width with the preset pulse width, the threshold value of the comparator is adjusted to realize negative feedback adjustment on the pulse width, and the difference between the measurement pulse width and the preset pulse width is adjusted until the difference meets a preset condition, so that the reliability of the positive optical communication is ensured.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and in particular to an optical communication device, an optical communication method, and a lidar. Background Technology

[0002] A lidar system is a radar system that uses laser beams to detect information such as the range, azimuth, altitude, speed, attitude, and shape of a target. A lidar system consists of a fixed base module and a rotating scanning module, which can be mounted on the base module with a 360° rotation capability. Because the scanning module and the base module rotate relative to each other, the scanning module cannot communicate with the base module via wired connections.

[0003] In related technologies, the scanning module communicates wirelessly with the base module via optical communication to send the data detected by the scanning module to the base module. To overcome signal pulse width variations during optical communication and ensure its reliability, lidar typically uses FPGA (Field Programmable Gate Array) encoding and decoding. However, due to the high cost of FPGA encoding and decoding, there is an urgent need for a new and reliable optical communication device and method in the market. Summary of the Invention

[0004] The purpose of this invention is to provide an optical communication device, an optical communication method, and a lidar, with the aim of providing a new and reliable optical communication device and method.

[0005] In a first aspect, this application provides an optical communication device for optical communication between a rotating component and a fixed component, wherein the rotating component rotates relative to the fixed component about a rotation axis located in an optical channel, and the optical communication device includes:

[0006] A first controller is mounted on the rotating component;

[0007] A first light-emitting device is mounted on the rotating component. The first light-emitting device is electrically connected to the first controller. The first light-emitting device is used to emit a first light signal and a preset light signal containing a preset pulse width into the light channel.

[0008] A first photosensitive device is mounted on the fixed component. The first photosensitive device is used to receive the first optical signal and the preset optical signal from the optical channel, and convert them into a first electrical signal and a preset electrical signal, respectively.

[0009] A comparator is mounted on the fixed component and electrically connected to the first photosensitive device. The comparator converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal, respectively, according to a threshold.

[0010] The second controller is installed on the fixed component and is electrically connected to the comparator. The second controller is used to receive the first pulse signal and the preset pulse signal and perform pulse width measurement. It is also used to compare the measured pulse width of the preset pulse signal and the preset pulse width of the preset optical signal, and adjust the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

[0011] In one embodiment, the first controller is electrically connected to the first light-emitting device via a first signal driving circuit.

[0012] In one embodiment, the first light-emitting device emits the first light signal and the preset light signal along the rotation axis.

[0013] In one embodiment, the first controller is a first microcontroller.

[0014] In one embodiment, the second controller is a second microcontroller.

[0015] In one embodiment, the first light-emitting device includes a light-emitting diode or a laser generator.

[0016] In one embodiment, the first photosensitive device includes a photodiode.

[0017] In one embodiment, the optical communication device further includes:

[0018] A second light-emitting device is installed on the fixed component. The second light-emitting device is electrically connected to the second controller. The second light-emitting device is used to emit a second light signal to the rotating component.

[0019] A second photosensitive device is mounted on the rotating component. The second photosensitive device is electrically connected to the first controller. The second photosensitive device is used to receive the second optical signal and convert it into a second electrical signal.

[0020] In this configuration, the first controller sends the rotation angle information of the rotating component to the first light-emitting device, and the second controller controls the second light-emitting device to emit light synchronously according to the rotation angle information.

[0021] In one embodiment, the light emission frequency of the second light-emitting device is synchronized with the rotation frequency of the rotating component.

[0022] In one embodiment, the light emitted by the second light-emitting device is directed toward the rotating component through the light channel.

[0023] In one embodiment, there is a gap between the light emitted by the second light-emitting device and the light emitted by the first light-emitting device.

[0024] In one embodiment, the light emitted by the second light-emitting device is spaced 0.1 mm to 10 mm from the axis of rotation.

[0025] Secondly, this application provides a lidar, which includes a base, a scanning module, and an optical communication device as described in any one of the above, wherein the base is a fixed component and the scanning module is a rotating component.

[0026] In one embodiment, the lidar further includes a code disk for acquiring the rotation information of the scanning module. The code disk is electrically connected to the first controller to send the rotation information to the first controller.

[0027] Thirdly, this application provides an optical communication method, which includes the following steps:

[0028] The first light-emitting device mounted on the rotating component emits a first light signal and a preset light signal containing a preset pulse width through the light channel;

[0029] The first photosensitive device installed on the fixed component receives the first optical signal and the preset optical signal, and converts them into the first electrical signal and the preset electrical signal, respectively.

[0030] The comparator converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal, respectively, based on a threshold.

[0031] The second controller measures the pulse width of the first pulse signal and the preset pulse signal, compares the measured pulse width of the preset pulse signal with the preset pulse width of the preset optical signal, and adjusts the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

[0032] In one embodiment, the preset condition refers to the difference between the measured pulse width and the preset pulse width being between -20% and +20% of the preset pulse width.

[0033] In one embodiment, the optical communication method further includes the following steps:

[0034] The second light-emitting device installed on the fixed component emits a second light signal;

[0035] The second photosensitive device installed on the rotating component receives the second optical signal and converts it into a second electrical signal.

[0036] In one embodiment, the first controller acquires the rotation angle information of the rotating component and transmits it to the second controller through the first light-emitting device; the second controller controls the second light-emitting device to synchronously emit the second light signal according to the rotation angle information.

[0037] The beneficial effects of the optical communication device, lidar, and optical communication method provided by this invention are as follows: The first controller emits a first optical signal through a first light-emitting device, the first photosensitive device receives the first optical signal and converts it into a first electrical signal, the comparator converts the first electrical signal into a first pulse signal according to a threshold, and the second controller receives the first pulse signal, realizing a non-contact forward communication connection between the rotating component and the fixed component. At the same time, the light emitted by the first light-emitting device propagates through the optical channel, approaching or coinciding with the rotation axis, and the pulse width of the first optical signal changes little. Furthermore, the first light-emitting device also emits a preset optical signal containing a preset pulse width, which is converted into a preset pulse signal by the first photosensitive device and the comparator. The second controller measures the measured pulse width of the preset pulse signal and compares it with the preset pulse width. By adjusting the threshold of the comparator, negative feedback adjustment of the pulse width is achieved until the difference between the measured pulse width and the preset pulse width meets the preset condition, ensuring the reliability of forward optical communication. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 A schematic diagram of the external structure of a lidar provided in an embodiment of the present invention;

[0040] Figure 2 for Figure 1 A cross-sectional view of the lidar in the image;

[0041] Figure 3 This is a schematic diagram of the forward communication connection of an optical communication device.

[0042] Figure 4 This is a schematic diagram illustrating the working principle of a comparator.

[0043] Figure 5 This is a schematic diagram of the reverse communication connection of an optical communication device.

[0044] Figure 6 This is another schematic diagram of the reverse communication connection of an optical communication device;

[0045] Figure 7A detailed schematic diagram of the optical communication device provided in the embodiments of the present invention;

[0046] Figure 8 This is a schematic flowchart of an optical communication method provided in an embodiment of the present invention.

[0047] The following are the labeling elements in the figure:

[0048] 100. Rotating component; 110. First controller; 111. First signal driving circuit; 120. First light-emitting device; 130. Second photosensitive device; 140. First rotating load; 150. Second rotating load; 160. Lens barrel; 170. Magnetic ring; 180. Code disk; 190. Filter cover;

[0049] 200. Fixed component; 210. Second controller; 211. Second signal drive circuit; 220. First photosensitive device; 230. Comparator; 240. Second light-emitting device; 250. Bottom shell; 260. Motor stator; 270. Bottom cover;

[0050] 300. Hollow axis; 310. Optical channel; 320. Rotation axis;

[0051] 410. Bearing; 420. Balance weight; 430. Backlash-eliminating spring; 440. Stop ring. Detailed Implementation

[0052] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0053] Throughout this specification, references to "an embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Therefore, the phrases "in one embodiment" or "in some embodiments" appear in various places throughout the specification, and not all refer to the same embodiment. Furthermore, in one or more embodiments, particular features, structures, or characteristics may be combined in any suitable manner.

[0054] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0055] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0056] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0057] Combination Figure 1 and Figure 2 The lidar can achieve 360° scanning. Since the scanning module (rotating component 100) rotates relative to the base (fixed component 200), data transmission between them cannot be achieved using wired communication. Therefore, optical communication can be used between the rotating component 100 and the fixed component 200. According to the inventor's understanding of relevant technologies, optical communication requires FPGA encoding / decoding to overcome signal pulse width variations during optical communication to ensure reliability. However, the high cost of FPGA encoding / decoding limits the application scope of this technology.

[0058] Specifically, the fixed component 200 is connected to a hollow shaft 300, which has an optical channel 310 for light to pass through. The optical channel 310 has a rotation axis 320 in its center, and the rotating component 100 is rotatably mounted on the fixed component 200 about the rotation axis 320. It can be understood that in other embodiments, the hollow shaft 300 is fixedly connected to the rotating component 100, and the hollow shaft 300 is rotatably mounted on the fixed component 200.

[0059] Example 1

[0060] Combination Figure 3This application provides an optical communication device for optical communication between a rotating component 100 and a fixed component 200. The optical communication device includes a first controller 110, a first light-emitting device 120, a first photosensitive device 220, a comparator 230, and a second controller 210.

[0061] The first controller 110 is mounted on the rotating component 100. Specifically, the first controller 110 is a microcontroller, a chip, or a discrete circuit board. When the first controller 110 is a microcontroller, it is small in size, programmable, functionally flexible, and has a lower cost compared to FPGA encoding / decoding, which is beneficial for miniaturization and cost control of optical communication devices. Optionally, the first controller 110 is fixedly mounted on the circuit board of the rotating component 100 and electrically connected to it to realize data transmission and power transmission, such as acquiring the rotation angle information of the rotating component 100 and acquiring data detected by the scanning module of the rotating component 100.

[0062] A first light-emitting device 120 is mounted on the rotating component 100 and electrically connected to a first controller 110. The first light-emitting device 120 emits a first optical signal and a preset optical signal containing a preset pulse width into the optical channel 310. The first controller 110 controls the on / off state and the on / off interval of the first light-emitting device 120 according to the data to be sent, thereby converting the data into an optical signal. Specifically, the first light-emitting device 120 includes a light-emitting diode (LED) or a laser generator. LEDs are smaller and have lower cost.

[0063] It should be noted that the first optical signal and the preset pulse width signal can be intertwined. In other words, the first optical signal contains a large number of signals carrying various information, and also includes the preset pulse width signal, meaning the preset pulse width signal is located within the first optical signal. Alternatively, the first optical signal and the preset pulse width signal can be transmitted separately. In other words, the first optical signal can be transmitted first, followed by the preset pulse width signal, or vice versa.

[0064] Specifically, the first controller 110 is electrically connected to the first light-emitting device 120 through a first signal driving circuit 111. In the illustrated embodiment, the input terminal of the first signal driving circuit 111 is electrically connected to the first controller 110, and the output terminal of the first signal driving circuit 111 is electrically connected to the first light-emitting device 120. The first signal driving circuit 111 enhances the driving capability, enabling the first light-emitting device 120 to stably emit a first light signal and a preset light signal.

[0065] The first photosensitive device 220 is mounted on the fixed component 200. The first photosensitive device 220 receives a first optical signal and a preset optical signal from the optical channel 310, and converts them into a first electrical signal and a preset electrical signal, respectively. The first photosensitive device 220 utilizes the photoelectric effect to convert the optical signal into an electrical signal, facilitating stable transmission of subsequent data in the form of current or voltage. Specifically, the first photosensitive device 220 includes a photodiode. When the photodiode is irradiated with light of a specific frequency emitted by the light-emitting diode, it generates a photocurrent. The presence and absence of photocurrent are converted by a circuit to generate high and low levels, representing 1 and 0, respectively. The high and low levels are converted according to a pre-agreed timing sequence, thus transmitting data. Since the photocurrent generated by the photodiode is greatly affected by the received light intensity, the reliability of optical communication is ultimately reflected in the pulse width output by the receiving circuit. Optionally, the first light-emitting device 120 is a 905nm light-emitting diode, and the first photosensitive device 220 is a 905nm photodiode.

[0066] It should be noted that excessive pulse width variation can cause the second controller 210 to sample incorrectly according to the agreed timing. Furthermore, the pulse width can also be affected by factors such as temperature, individual differences in photodiodes, and assembly, leading to sampling errors, i.e., communication errors.

[0067] The comparator 230 is mounted on the fixed component 200 and is electrically connected to the first photosensitive device 220. The comparator 230 converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal respectively according to the threshold.

[0068] The second controller 210 is installed on the fixed component 200. The second controller 210 is electrically connected to the comparator 230. The second controller 210 is used to receive the first pulse signal and the preset pulse signal and perform pulse width measurement. It is also used to compare the measured pulse width of the preset pulse signal and the preset pulse width of the preset optical signal, and adjust the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

[0069] The second controller 210 sends an initial threshold to the comparator 230 in advance. The comparator 230 converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal respectively according to the initial threshold. Then, the second controller 210 adjusts the threshold according to the comparison result of the measured pulse width of the preset pulse signal and the preset pulse width of the preset optical signal, and sends it to the comparator 230.

[0070] Optionally, the second controller 210 is a second microcontroller, which is beneficial for miniaturization and cost control of the optical communication device. In the illustrated embodiment, the second controller 210 is fixedly mounted on the circuit board of the fixing component 200 and electrically connected to the circuit board of the fixing component 200 to realize data transmission and power transmission.

[0071] refer to Figure 4 When the preset threshold is threshold 1, the pulse width of the obtained pulse signal decreases. When the preset threshold is threshold 2, the pulse width of the obtained pulse signal increases. It is evident that the threshold affects the pulse width; adjusting the threshold allows for pulse width adjustment, ensuring the accuracy of optical communication.

[0072] Specifically, when the preset electrical signal passes through the circuit of comparator 230, the pulse width of the signal output from comparator 230 changes accordingly when the threshold of comparator 230 is controlled by the second controller 210. Within a certain range, raising the threshold of comparator 230 can reduce the output signal pulse width, and vice versa. Thus, the second controller 210 measures the measured pulse width of the preset pulse signal and compares it with the preset pulse width. If the difference between the measured pulse width and the preset pulse width does not meet the preset condition, the threshold of comparator 230 is adjusted to achieve negative feedback regulation of the pulse width until the difference between the measured pulse width and the preset pulse width meets the preset condition.

[0073] In this application, the optical communication connection through which the first controller 110 transmits information to the second controller 210 via the first light-emitting device 120, the first photosensitive device 220, and the comparator 230 is defined as a forward communication connection. When the difference between the measured pulse width and the preset pulse width meets the preset conditions, it indicates that the information sent by the first controller 110 through the forward communication connection is transmitted to the second controller 210 relatively accurately, thus ensuring the reliability of the forward optical communication.

[0074] Specifically, the preset condition refers to the difference between the measured pulse width and the preset pulse width being between -20% and +20% of the preset pulse width, meaning the accuracy of information transmitted via the forward communication connection is at least 80%. This ensures that even if the external environment changes, the signal pulse width remains within a suitable range, guaranteeing that the signal quality is maintained at a level that allows the second controller 210 to directly resolve the signal without errors. Under this mechanism, regardless of the environment in which the optical communication device or lidar is powered on, even if the initial signal cannot be resolved, it can be quickly adjusted to a suitable state by measuring the pulse width.

[0075] In some embodiments, the tolerance for pulse width may vary due to differences in communication parameters and devices. The preset condition may also measure the difference between the measured pulse width and the preset pulse width as being between -5% and +5% of the preset pulse width, or between -10% and +10% of the preset pulse width.

[0076] It is understandable that the preset condition can also be that the difference between the measured pulse width and the preset pulse width is less than a certain absolute value. For example, the preset condition can also be that the difference between the measured pulse width and the preset pulse width is less than ±5ms (milliseconds). Alternatively, the preset condition can also be that the difference between the measured pulse width and the preset pulse width is between -20% and +20% of the measured pulse width.

[0077] In the aforementioned optical communication device, the first controller 110 emits a first optical signal through the first light-emitting device 120, the first photosensitive device 220 receives the first optical signal and converts it into a first electrical signal, the comparator 230 converts the first electrical signal into a first pulse signal according to a threshold, and the second controller 210 receives the first pulse signal, thus realizing a non-contact forward communication connection between the rotating component 100 and the fixed component 200. The aforementioned optical communication device utilizes the communication peripherals built into the first controller 110 to achieve reliable optical communication, significantly reducing the cost of the optical communication device. Simultaneously, the aforementioned optical communication device utilizes preset pulse width and threshold adjustment to achieve reliable optical communication, adapting to pulse width variations caused by environmental conditions and device differences, eliminating the need for debugging during the production stage, and having low requirements for assembly concentricity.

[0078] In some embodiments, combined with Figure 3 Due to the rotation axis 320 (see Figure 2 The light emitted by the first light-emitting device 120 propagates through the optical channel 310 and is close to or coincides with the rotation axis 320. The pulse width of the first optical signal changes little, which further increases the reliability of the forward communication connection.

[0079] Specifically, in combination Figure 1 The first light-emitting device 120 emits a first optical signal and a preset optical signal along the rotation axis 320. In other words, the first optical signal and the preset optical signal emitted by the first light-emitting device 120 are fixed in position relative to the fixed component 200, and the pulse width changes very little, further improving the reliability of optical communication.

[0080] Specifically, the first light-emitting device 120 and the first photosensitive device 220 are arranged opposite to each other. The closer the first light-emitting device 120 and the first photosensitive device 220 are to the rotation axis 320, the less the pulse width output by the first photosensitive device 220 is affected by rotational changes. Conversely, the farther the first photosensitive device 220 is from the rotation axis 320, the more drastically the pulse width output by the first photosensitive device 220 is affected by rotational changes. Figure 1 In the illustrated embodiment, the first light-emitting device 120 is located on the rotation axis 320 of the light channel 310. The first light-emitting device 120 is mounted on the circuit board of the rotating component 100 and is located inside one end of the hollow shaft 300. The light-emitting end of the first light-emitting device 120 faces the other end of the hollow shaft 300. The length direction of the first light-emitting device 120 coincides with the rotation axis 320. The first photosensitive device 220 is mounted on the circuit board of the fixing component 200 and is located inside the other end of the hollow shaft 300. The first photosensitive device 220 is located on the rotation axis 320.

[0081] In some embodiments, combined with Figure 5The optical communication device further includes a second light-emitting device 240 and a second photosensitive device 130. The second light-emitting device 240 is mounted on the fixed component 200 and electrically connected to the second controller 210. The second light-emitting device 240 is used to emit a second optical signal to the rotating component 100. The second photosensitive device 130 is mounted on the rotating component 100 and electrically connected to the first controller 110. The second photosensitive device 130 is used to receive the second optical signal and convert it into a second electrical signal.

[0082] In this application, the optical communication connection through which the second controller 210 transmits information to the first controller 110 via the second light-emitting device 240 and the second photosensitive device 130 is defined as a reverse communication connection. Since the rotating component 100 rotates relative to the fixed component 200, i.e., the first controller 110 rotates relative to the second controller 210, the second electrical signal exhibits pulse width variations. To improve the reliability of the reverse communication connection, the first controller 110 sends the rotation angle information of the rotating component 100 to the first light-emitting device 120, i.e., it uses the forward communication connection to transmit the rotation angle information of the rotating component 100 and obtain the clock information of the rotating component 100. The second controller 210 then controls the second light-emitting device 240 to synchronously emit the second optical signal according to the rotation angle information.

[0083] Specifically, the emission frequency of the second light-emitting device 240 is synchronized with the rotation frequency of the rotating component 100. For example, the code disk 180 is used to measure the rotation angle information of the rotating component 100. The code disk 180 serves as the clock for the reverse communication connection. The rotation angle information measured by the code disk 180 is synchronized to the second controller 210 through the forward communication connection. The I / O operation of the second controller 210 is used to synchronize the flip frequency (emission frequency) of the signal emitted by the second light-emitting device 240 with the trigger frequency of the code disk 180. The second photosensitive device 130 samples and receives signals according to the trigger frequency of the code disk 180, thus realizing a highly reliable reverse communication connection.

[0084] It is understood that in other embodiments, the rotation frequency of the rotating component 100 is an integer multiple of the light emission frequency of the second light-emitting device 240.

[0085] Specifically, the second light-emitting device 240 can be selected as a light-emitting diode or a laser generator, such as a 580nm light-emitting diode. The second photosensitive device 130 can be selected as a photodiode, such as a 580nm photodiode.

[0086] Specifically, the second controller 210 is electrically connected to the second light-emitting device 240 through the second signal driving circuit 211. In the illustrated embodiment, the input terminal of the second signal driving circuit 211 is electrically connected to the second controller 210, and the output terminal of the second signal driving circuit 211 is electrically connected to the second light-emitting device 240. The second signal driving circuit 211 enhances the driving capability, enabling the second light-emitting device 240 to stably emit the second light signal.

[0087] In one embodiment, combined Figure 6 The light emitted by the second light-emitting device 240 is directed towards the rotating component 100 through the light channel 310. Due to the rotation axis 320 (see...) Figure 2 The light emitted by the second light-emitting device 240 propagates through the optical channel 310 and is close to the rotation axis 320. The pulse width of the second optical signal changes little, which further increases the reliability of the reverse communication connection.

[0088] Specifically, the light emitted by the second light-emitting device 240 is spaced apart from the light emitted by the first light-emitting device 120 to avoid interference between the two. The light emitted by the second light-emitting device is spaced 0.1mm to 10mm away from the rotation axis 320, which avoids drastic changes in the pulse width of the signal received by the second photosensitive device 130, and also prevents the light emitted by the second light-emitting device 240 from getting too close to the rotation axis 320 and interfering with the light emitted by the first light-emitting device 120.

[0089] Optionally, the distance between the light emitted by the second light-emitting device and the rotation axis 320 is 0.1mm, 0.2mm, 0.5mm, 1mm, 2mm, 3mm, 5mm, 8mm or 10mm.

[0090] It should be noted that, because the light-emitting device has a certain divergence angle, even if the light-emitting device and the photosensitive device are not directly opposite each other, some of the divergent light from the light-emitting device can still enter the photosensitive device. Therefore, the reverse communication connection can achieve optical communication even with relative rotation. That is, the light-emitting device and the photosensitive device do not need to be directly opposite each other. In this embodiment, the first light-emitting device 120 and the first photosensitive device 220 can be directly opposite each other or staggered; the second light-emitting device 240 and the second photosensitive device 130 can be directly opposite each other or staggered.

[0091] In one embodiment, the second light-emitting device 240 and the second photosensitive device 130 are disposed opposite to each other. The second light-emitting device 240 is mounted on the circuit board of the fixing member 200 and is located within the hollow shaft 300 near the fixing member 200. The light-emitting end of the second light-emitting device 240 faces the other end of the hollow shaft 300. The length direction of the second light-emitting device 240 is parallel to the rotation axis 320. The second photosensitive device 130 is mounted on the circuit board of the rotating member 100 and is located within the hollow shaft 300 near the rotating member 100. The second photosensitive device 130 is parallel to the rotation axis 320.

[0092] In summary, combining Figure 7 The optical communication device provided in this embodiment has a specific structure that enables bidirectional communication. Both bidirectional communications propagate light through the optical path of the hollow axis 300, which is located on the central axis of the lidar. The transmitting and receiving units for forward and reverse optical communication are placed exactly on or adjacent to the rotation axis 320, and reliable communication is maintained through pulse width modulation or a code disk clock 180.

[0093] Example 2

[0094] Combination Figure 1 and Figure 2 This application provides a lidar, including a base, a scanning module, and any one of the optical communication devices described in Embodiment 1. The base is a fixed component 200, and the scanning module is a rotating component 100. This lidar can achieve a highly reliable forward communication connection, and further, it can also achieve a highly reliable reverse communication connection.

[0095] Specifically, the lidar also includes an encoder 180, which is used to acquire the rotation information of the scanning module. The encoder 180 is electrically connected to the first controller 110 to send the rotation information to the first controller 110. Thus, by means of the lidar's own encoder 180, the rotation information of the scanning module is acquired and sent to the second controller 210 through a forward communication connection.

[0096] Furthermore, the lidar of this application also has any specific structure of the optical communication device in Embodiment 1, which will not be described in detail here.

[0097] The specific structure of the lidar is further described below. The scanning module also includes a first rotating load 140, a second rotating load 150, and a magnetic ring 170. The base also includes a bottom shell 250, a motor stator 260, and a bottom cover 270. The hollow shaft 300 is fixedly mounted on the bottom cover 270. The motor stator 260 is fixedly sleeved on the hollow shaft 300. The first rotating load 140 is rotatably sleeved on the hollow shaft 300 through a bearing 410. The first rotating load 140 is also sleeved on the motor stator 260. The second rotating load 150 is fixedly connected to the first rotating load 140. The magnetic ring 170 is fixedly mounted on the second rotating load 150, so that the magnetic ring 170 rotates under the action of the motor stator 260.

[0098] The bottom shell 250 is detachably mounted on the bottom cover 270, and the bottom shell 250 and the bottom cover 270 enclose a mounting cavity. The hollow shaft 300, the first rotating load 140 and the second rotating load 150 are located in the mounting cavity.

[0099] Specifically, the motor stator 260 and the hollow shaft 300 are coaxially arranged. The magnetic ring 170 and the second rotating load 150 are coaxially arranged. The magnetic ring 170 is located on the side of the second rotating load 150 away from the motor stator 260.

[0100] Specifically, the code disk 180 is fixedly mounted on the bottom shell 250. The code disk 180 is sleeved on the second rotating load 150, and the code disk 180 and the second rotating load 150 are coaxially arranged. A wireless charging transmitting coil is mounted on the peripheral side of the code disk 180, and a wireless charging receiving coil is mounted on the second rotating load 150.

[0101] Specifically, a counterweight 420 is installed on the top of the second rotating load 150. The counterweight 420 has multiple screw mounting holes. By adjusting the mounting position and number of screws on the counterweight 420, the counterweight can be adjusted.

[0102] Specifically, a bearing 410 is sleeved on the outer side of the hollow shaft 300, and the bearing 410 is located between the hollow shaft 300 and the first rotating load 140. In the illustrated embodiment, there are two bearings 410, and an axial backlash-eliminating spring 430 is installed between the two bearings 410. The backlash-eliminating spring 430 supports the two bearings 410 from above and below to eliminate vertical backlash and reduce the noise when the bearings 410 are working.

[0103] The hollow shaft 300 is fitted with a retaining ring 440. The retaining ring 440 abuts against the side of the bearing 410 away from the bottom cover 270 to prevent the bearing 410 from moving axially.

[0104] The lidar also includes a lens barrel 160, the interior of which undergoes an anti-light treatment to reduce the influence of stray light. After being fixed to the second rotating load 150, the lens barrel 160 rotates 360° to achieve omnidirectional scanning. The lens barrel 160 is located outside the mounting cavity. In the illustrated embodiment, the lidar also includes a filter 190, which is fitted onto the lens barrel 160.

[0105] Example 3

[0106] This application provides an optical communication method. Combined with... Figure 8 The optical communication method includes the following steps:

[0107] S100: The first light-emitting device 120 mounted on the rotating component 100 emits a first light signal and a preset light signal containing a preset pulse width through the light channel 310.

[0108] S200: The first photosensitive device 220 installed on the fixed component 200 receives the first optical signal and the preset optical signal, and converts them into the first electrical signal and the preset electrical signal respectively.

[0109] S300: Comparator 230 combines a preset threshold to convert the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal, respectively.

[0110] S400: The second controller 210 measures the pulse width of the first pulse signal and the preset pulse signal, compares the measured pulse width of the preset pulse signal with the preset pulse width of the preset optical signal, and adjusts the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

[0111] In the above method, the first controller 110 emits a first optical signal through the first light-emitting device 120, the first photosensitive device 220 receives the first optical signal and converts it into a first electrical signal, the comparator 230 converts the first electrical signal into a first pulse signal according to a threshold, and the second controller 210 receives the first pulse signal. That is, the rotating component 100 uses optical communication to achieve a non-contact forward communication connection with the fixed component 200. When the difference between the measured pulse width and the preset pulse width meets the preset conditions, it indicates that the information sent by the first controller 110 through the forward communication connection is transmitted to the second controller 210 relatively accurately, ensuring the reliability of the forward optical communication.

[0112] Specifically, the preset condition refers to the difference between the measured pulse width and the preset pulse width being between -20% and +20% of the preset pulse width. This ensures that even if the external environment changes, the signal pulse width remains within a suitable range, guaranteeing that the signal quality is maintained at a level that the second controller 210 can directly resolve without errors. Under this mechanism, regardless of the environment in which the optical communication device or lidar is powered on, even if the initial signal cannot be resolved, it can be quickly adjusted to a suitable state by measuring the pulse width.

[0113] In some embodiments, the preset conditions may also measure the difference between the pulse width and the preset pulse width as being between -10% and +10% of the preset pulse width, or between -5% and +5% of the preset pulse width, or between -2% and +2% of the preset pulse width.

[0114] In one embodiment, the optical communication method further includes the following steps:

[0115] S510: The second light-emitting device 240, which is installed on the fixed component 200, emits a second light signal.

[0116] S520: The second photosensitive device 130 installed on the rotating component 100 receives the second optical signal and converts it into a second electrical signal.

[0117] Thus, the second controller 210 achieves a reverse communication connection by transmitting information to the first controller 110 through the optical communication connection of the second light-emitting device 240 and the second photosensitive device 130.

[0118] Specifically, the first controller 110 acquires the rotation angle information of the rotating component 100 and transmits it to the second controller 210 through the first light-emitting device 120. The second controller 210 controls the second light-emitting device 240 to synchronously emit a second light signal according to the rotation angle information.

[0119] To improve the reliability of the reverse communication connection, the first controller 110 sends the rotation angle information of the rotating component 100 to the first light-emitting device 120, that is, it uses the forward communication connection to transmit the rotation angle information of the rotating component 100 and obtains the clock information of the rotating component 100. The second controller 210 controls the second light-emitting device 240 to synchronously emit the second light signal according to the rotation angle information.

[0120] Furthermore, the optical communication method in Embodiment 3 can be implemented using the optical communication device in Embodiment 1, and has the specific structure of the optical communication device in Embodiment 1, which will not be described in detail here.

[0121] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An optical communication device for optical communication between a rotating component and a fixed component, wherein the rotating component rotates relative to the fixed component about a rotation axis located in an optical channel, characterized in that, The optical communication device includes: A first controller is mounted on the rotating component; A first light-emitting device is mounted on the rotating component. The first light-emitting device is electrically connected to the first controller. The first light-emitting device is used to emit a first light signal and a preset light signal containing a preset pulse width into the light channel. A first photosensitive device is mounted on the fixed component. The first photosensitive device is used to receive the first optical signal and the preset optical signal from the optical channel, and convert them into a first electrical signal and a preset electrical signal, respectively. A comparator is mounted on the fixed component and electrically connected to the first photosensitive device. The comparator converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal, respectively, according to a threshold. The second controller is installed on the fixed component and is electrically connected to the comparator. The second controller is used to receive the first pulse signal and the preset pulse signal and perform pulse width measurement. It is also used to compare the measured pulse width of the preset pulse signal and the preset pulse width of the preset optical signal, and adjust the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

2. The optical communication device according to claim 1, characterized in that: The first controller is electrically connected to the first light-emitting device through a first signal driving circuit.

3. The optical communication device according to claim 1, characterized in that: The first light-emitting device emits the first light signal and the preset light signal along the rotation axis.

4. The optical communication device according to claim 1, characterized in that: The optical communication device further includes at least one of the following features: The first controller is a first microcontroller; The second controller is a second microcontroller; The first light-emitting device includes a light-emitting diode or a laser generator; The first photosensitive device includes a photodiode.

5. The optical communication device according to any one of claims 1 to 4, characterized in that: The optical communication device further includes: A second light-emitting device is installed on the fixed component. The second light-emitting device is electrically connected to the second controller. The second light-emitting device is used to emit a second light signal to the rotating component. A second photosensitive device is mounted on the rotating component. The second photosensitive device is electrically connected to the first controller. The second photosensitive device is used to receive the second optical signal and convert it into a second electrical signal. In this configuration, the first controller sends the rotation angle information of the rotating component to the first light-emitting device, and the second controller controls the second light-emitting device to emit light synchronously according to the rotation angle information.

6. The optical communication device according to claim 5, characterized in that: The light emission frequency of the second light-emitting device is synchronized with the rotation frequency of the rotating component.

7. The optical communication device according to claim 5, characterized in that: The light emitted by the second light-emitting device is directed toward the rotating component through the light channel; there is a gap between the light emitted by the second light-emitting device and the light emitted by the first light-emitting device; there is a gap of 0.1 mm to 10 mm between the light emitted by the second light-emitting device and the rotation axis.

8. A lidar, characterized in that: The lidar includes a base, a scanning module, and an optical communication device as described in any one of claims 1 to 7, wherein the base is a fixed component and the scanning module is a rotating component.

9. The lidar according to claim 8, characterized in that: The lidar also includes a code disk, which is used to acquire the rotation information of the scanning module. The code disk is electrically connected to the first controller to send the rotation information to the first controller.

10. An optical communication method, characterized in that: The optical communication method includes the following steps: The first light-emitting device mounted on the rotating component emits a first light signal and a preset light signal containing a preset pulse width through the light channel; The first photosensitive device installed on the fixed component receives the first optical signal and the preset optical signal, and converts them into the first electrical signal and the preset electrical signal, respectively. The comparator converts the first electrical signal and the preset electrical signal into a first pulse signal and a preset pulse signal, respectively, based on a threshold. The second controller measures the pulse width of the first pulse signal and the preset pulse signal, compares the measured pulse width of the preset pulse signal with the preset pulse width of the preset optical signal, and adjusts the threshold according to the comparison result until the difference between the measured pulse width and the preset pulse width meets the preset condition.

11. The optical communication method according to claim 10, characterized in that: The preset condition refers to the difference between the measured pulse width and the preset pulse width being between -20% and +20% of the preset pulse width.

12. The optical communication method according to claim 10, characterized in that: The optical communication method further includes the following steps: The second light-emitting device installed on the fixed component emits a second light signal; The second photosensitive device installed on the rotating component receives the second optical signal and converts it into a second electrical signal.

13. The optical communication method according to claim 12, characterized in that: The first controller acquires the rotation angle information of the rotating component and transmits it to the second controller through the first light-emitting device; the second controller controls the second light-emitting device to synchronously emit the second light signal according to the rotation angle information.

Images