Patent Publication Number: US-2020292697-A1

Title: Radar device, wireless rotating device of radar, and unmanned aerial vehicle

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of International Application No. PCT/CN2017/117004, filed Dec. 18, 2017, the entire content of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to radar technology area and, more particularly, to a radar device, a radar wireless rotating device, and an unmanned aerial vehicle (UAV). 
     BACKGROUND 
     With rapid development of unmanned aerial vehicle (UAV) technology and improvement of radar miniaturization technology, radar gradually becomes an important part of the UAV. An antenna assembly as a core component of the radar is driven by a drive mechanism when the radar is working, for example driven by an electric motor, to rotate around a rotation axis to detect obstacles of different directions. In conventional technologies, a cable is configured to connect the antenna assembly to an external power source to supply power to the antenna assembly. However, with this power supply method, due to limitation of the cable, a rotation angle of the drive mechanism is limited. For example, the rotation angle may only reach 270°. A rotation of 360° of the antenna assembly, such as an omnidirectional rotation, is not possible. 
     SUMMARY 
     In accordance with the disclosure, there is provided an unmanned aerial vehicle (UAV) including a housing and a radar device. The radar device is mounted at the housing and includes a base, an antenna assembly, a power transmitter assembly, and a power receiver assembly. The antenna assembly is arranged at the base and configured to rotate relative to the base around a rotation axis. The power transmitter assembly is configured to convert electric power into electromagnetic energy and transmit the electromagnetic energy. The power receiver assembly is disposed at a distance from the power transmitter assembly, is electrically connected to the antenna assembly, and is configured to rotate with the antenna assembly, convert the electromagnetic energy into electric power, and transmit the electric power to the antenna assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic structural diagram of a radar device provided by embodiments of the present disclosure. 
         FIG. 2  is a sectional view of the radar device shown in  FIG. 1 . 
         FIG. 3  is a schematic structural diagram of a power transmitter assembly and a power receiver assembly of the radar device shown in  FIG. 1 . 
         FIG. 4  is a schematic structural diagram of a first wireless communication assembly and a second wireless communication assembly of the radar device shown in  FIG. 1 . 
         FIG. 5  is an unmanned aerial vehicle (UAV) including the radar device shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, technical solutions of the embodiments of the present disclosure are described clearly in connection with the drawings. The described embodiments are merely some of the embodiments of the present disclosure, but not all the embodiments. Based on the described embodiments of the disclosure, all other embodiments obtained by one of ordinary skill in the art without any creative effort are within the scope of the present disclosure. 
     In accordance with the present disclosure, a radar device, a wireless rotating device, and an unmanned aerial vehicle (UAV) are described in detail in connection with the drawings as follows. Features of below described embodiments and implementations may be combined as long as there is no conflict, and technical solutions created by combining the features of the embodiments and implementations are also embodiments of the present disclosure. 
       FIG. 1  and  FIG. 2  are a schematic structural diagram and a sectional view of a radar device  100  provided by the embodiments of the present disclosure. As shown in  FIG. 1  and  FIG. 2 , the radar device  100  includes a base  110 , an antenna assembly  120 , an antenna bracket  140  configured to support the antenna assembly  120 , an electric motor  130 , a power transmitter assembly  200 , and a power receiver assembly  300 . 
     As shown in  FIG. 1 , the antenna assembly  120  is arranged at the base  110  and can rotate around a rotation axis relative to the base  110 . The rotation axis may be a physical axis or a virtual axis. When the rotation axis is a physical axis, the antenna assembly  120  may rotate relative to the rotation axis or may rotate together with the rotation axis. The electric motor  130  is arranged at the base  110  and includes a rotor  131  connected to the antenna assembly  120 . The electric motor  130  is configured to drive the antenna bracket  140  to rotate, such that the antenna assembly  120  rotates with the antenna bracket  140  around the above-described rotation axis. The power transmitter assembly  300  and the power receiver assembly  400  are arranged with an interval therebetween. The power receiver assembly is electrically connected to the antenna assembly  120  and can rotate together with the antenna assembly  120 . The power receiver assembly may cooperate with the power transmitter assembly to supply power to the antenna assembly  120 , such that the antenna assembly  120  can work in normal. 
     In connection with the drawings, structures of the power receiver assembly and the power transmitter assembly, the cooperation of the power receiver assembly and the power transmitter assembly, and specific implementation principles and implementation processes of supplying power to the antenna assembly  120  are described in detail. 
     In the above-described radar device  100  shown in  FIG. 1  and  FIG. 2 , the power transmitter assembly  200  is fixed and arranged at the base  110  shown in  FIG. 1 . The power receiver assembly is fixedly mounted at the antenna bracket  140  and rotates together with the antenna assembly. 
     The structures, working principles, and working processes of the power transmitter assembly and the power receiver assembly are described in detail. 
       FIG. 3  is a schematic structural diagram of the power transmitter assembly  200  and the power receiver assembly  300  of the radar device shown in  FIG. 1 . 
     As shown in  FIG. 3 , the power transmitter assembly  200  includes a power supply circuit board  210 , a transmitter control chip  220 , a transmitter current adjustment circuit  230 , and a transmitter coil  240 . 
     The power supply circuit board  210  is electrically connected to the transmitter control chip  220  and the transmitter current adjustment circuit  230  and can supply power to the transmitter control chip  220  and the transmitter current adjustment circuit  230 . In the embodiments, current supplied by the power supply circuit board  210  is direct current (DC). An intensity of the DC may be constant or dynamically changed, which is not limited by the present disclosure. The transmitter control chip  220  is electrically connected to the transmitter current adjustment circuit  230  and may be configured to control the transmitter current adjustment circuit  230  to convert the received DC power into alternating current (AC) power with a preset frequency range. 
     The transmitter current adjustment circuit  230  is electrically connected to the transmitter coil  240  and can transmit the converted AC power to the transmitter coil  240 . The transmitter coil  240  can convert the received AC power into electromagnetic energy and transmit the electromagnetic energy. 
     In one embodiment, to convert the DC power into the AC power with the preset frequency range, the above-described transmitter current adjustment circuit  230  may include a transmitter current conversion circuit and a resonance circuit. The transmitter current conversion circuit is electrically connected to the resonance circuit. The transmitter current conversion circuit may use an “inverter” principle to convert the DC power provided by the power supply circuit board  210  into the AC power and transmit the converted AC power to the resonance circuit. Further, the resonance circuit can adjust a frequency of the received AC power to the preset frequency range. 
     As shown in  FIG. 3 , the power receiver assembly  300  includes a receiver control chip  310 , a receiver current adjustment circuit  320 , and a receiver coil  330 . As shown in  FIG. 3 , the receiver coil  330  is disposed at a distance from the transmitter coil  240 , and electrical power can be transmitted between the receiver coil  330  and the transmitter coil  240 . The receiver coil  330  is electrically connected to the receiver current adjustment circuit  320 . Since the receiver coil  330  is disposed at a distance from the transmitter coil  240 , the electromagnetic energy transmitted by the transmitter coil  240  can be sensed. Based on the principle of electromagnetic induction, the received electromagnetic energy is converted into the AC power, and the AC power is transmitted to the receiver current adjustment circuit  320 . Further, the receiver current adjustment circuit  320  is electrically connected to the receiver control chip  310 . The receiver current adjustment circuit  320  can be controlled by the receiver control chip  310  to perform processing of rectification, filtering, etc., to the received AC power to convert the received AC power into the DC power. The receiver current adjustment circuit  320  is electrically connected to the antenna assembly  120  and can transmit the DC power to the antenna assembly  120  to supply power to the antenna assembly  120  to ensure that the antenna  120  works normally. 
     In some embodiments, the electric power transmission efficiency is related to the distance between the transmitter coil  240  and the receiver coil  330 . If the distance between the transmitter coil  240  and the receiver coil  330  is too small, a mutual inductance phenomenon occurs between the transmitter coil  240  and the receiver coil  330 , which affects the transmission efficiency. If the distance between the transmitter coil  240  and the receiver coil  330  is too large, the transmission distance is long, which affects the transmission efficiency. Therefore, the distance between the transmitter coil  240  and the receiver coil  330  may need to be within an appropriate range. In some embodiments, the distance between the transmitter coil  240  and the receiver coil  330  is controlled to be in the distance range of 1.5 mm˜5 mm. For example, the distance between the transmitter coil  240  and the receiver coil  330  may be 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, and 5.0 mm. 
     Further, based on the distance range between the transmitter coil  240  and the receiver coil  330 , and in order to ensure the subsequent DC power provided by the power receiver assembly  300  to the antenna assembly  120  can satisfy the current intensity needed by the antenna assembly  120  during normal operation, embodiments of the present disclosure also provide a configuration described below. 
     In some embodiments, the electric power transmission efficiency is related to an inductance value of the transmitter coil  240 . If the inductance value of the transmitter coil  240  is too large or too small, a coupling degree between the transmitter coil  240  and a capacitor is reduced, which affects the transmission efficiency. Therefore, the inductance value of the transmitter coil  240  may need to be within an appropriate range. In some embodiments, the inductance value of the above-described transmitter coil  240  may be controlled to be in the inductance value range of 8.5 uH˜11 uH. For example, the inductance value of the above-described transmitter coil  240  may be 8.5 uH, 8.6 uH, 8.7 uH, 8.8 uH, 8.9 uH, 9.0 uH, 9.1 uH, 9.2 uH, 9.3 uH, 9.4 uH, 9.5 uH, 9.6 uH, 9.7 uH, 9.8 uH, 9.9 uH, 10.0 uH, 10.1 uH, 10.2 uH, 10.3 uH, 10.4 uH, 10.5 uH, 10.6 uH, 10.7 uH, 10.8 uH, 10.9 uH, and 11.0 uH. 
     In some embodiments, the electric power transmission efficiency is related to an inductance value of the receiver coil  330 . If the inductance value of the receiver coil  330  is too large or too small, a coupling degree between the receiver coil  330  and a capacitor is reduced, which affects the transmission efficiency. Therefore, the inductance value of the receiver coil  330  may need to be within an appropriate range. In some embodiments, the inductance value of the above-described receiver coil  330  may be controlled to be in the inductance value range of 7.5 uH˜11 uH. For example, the inductance value of the above-described receiver coil  330  may be 7.5 uH, 7.6 uH, 7.7 uH, 7.8 uH, 7.9 uH, 8.0 uH, 8.1 uH, 8.2 uH, 8.3 uH, 8.4 uH, 8.5 uH, 8.6 uH, 8.7 uH, 8.8 uH, 8.9 uH, 9.0 uH, 9.1 uH, 9.2 uH, 9.3 uH, 9.4 uH, 9.5 uH, 9.6 uH, 9.7 uH, 9.8 uH, 9.9 uH, 10.0 uH, 10.1 uH, 10.2 uH, 10.3 uH, 10.4 uH, 10.5 uH, 10.6 uH, 10.7 uH, 10.8 uH, 10.9 uH, and 11.0 uH. 
     In some embodiments, the electric power transmission efficiency is related to a frequency of the AC power. If the frequency of the AC power is too large or too small, power consumption of the power transmitter assembly  200  and/or the power receiver assembly  300  increases, which affects the transmission efficiency. Therefore, the frequency of the AC power may need to be within an appropriate range. In some embodiments, a preset frequency range may be 120 KHz˜150 KHz. For example, the above-described preset frequency may be 120 KHz, 121 KHz, 122 KHz, 123 KHz, 124 KHz, 125 KHz, 126 KHz, 127 KHz, 128 KHz, 129 KHz, 130 KHz, 131 KHz, 132 KHz, 133 KHz, 134 KHz, 135 KHz, 136 KHz, 137 KHz, 138 KHz, 139 KHz, 140 KHz, 141 KHz, 142 KHz, 143 KHz, 144 KHz, 145 KHz, 146 KHz, 147 KHz, 148 KHz, 149 KHz, and 150 KHz. 
     In the radar device shown in  FIG. 1 , the power transmitter assembly is fixedly mounted at the base, the power receiver assembly is electrically connected to the antenna assembly, and the power receiver assembly is configured to rotate together with the antenna assembly. Further, the power transmitter assembly converts the received DC power into electromagnetic energy based on the principle of electromagnetic inductance, and transmits the electromagnetic energy, and the power receiver assembly converts the received electromagnetic energy into the DC power and transmits the DC power to the antenna assembly electrically connected to the power receiver assembly. That is, wireless power supply to the antenna assembly is realized. With this power supply method, since a cable is not needed to connect the antenna assembly to the external power source, the limitation of the cable is eliminated, such that the electric motor realize 360° omnidirectional rotation to drive the antenna to realize 360° omnidirectional rotation to better detect obstacles at different directions. 
     In some embodiments, the antenna assembly  120  also needs to transmit the detected information to a ground station and receive request instructions sent from the ground station. Thus, embodiments of the present disclosure also provide wireless communication. 
     In some embodiments, the radar device shown in  FIG. 1  further includes a first wireless communication assembly  500  and a second wireless communication assembly  400  (not shown in  FIG. 1 ). There is a wireless communication connection between the first wireless communication assembly  500  and the second wireless communication assembly  400 . Based on a similar principle of the wireless power supply, the first communication assembly  500  is mounted at the antenna bracket  140  and is electrically connected to the antenna assembly  120 , and the second communication assembly  400  is fixedly mounted at the base  110 . 
     Based on an above-described structure, the first wireless communication assembly  500  can be configured to transmit the information detected by the antenna assembly  120  to the second wireless communication assembly  400  and receive the request instructions sent by the second wireless communication assembly  400 . 
     In connection with the drawings, the structures of each of the first wireless communication assembly  500  and the second wireless communication assembly  400 , and the implementation principle and implementation process of the wireless communication therebetween are described in detail as follows. 
     In the embodiments of the present disclosure, considering the volume and the structure of the miniature radar, an integrated chip solution may be used to integrate the power transmitter assembly  200  and the second wireless communication assembly  400  shown in  FIG. 3  to a same electric circuit board. Correspondingly, the integrated chip solution may also be used to integrate the power receiver assembly  300  and the first wireless communication assembly shown in  FIG. 3  to a same electric circuit board. 
       FIG. 4  shows the first wireless communication assembly  500  and the second wireless communication assembly  400 . As shown in  FIG. 4 , the first wireless communication assembly  500  and the power receiver assembly  300  are integrated at the receiver circuit board, which is electrically connected to the receiver current adjustment circuit  320  of the power receiver assembly  300 , such that the receiver current adjustment circuit  320  supplies power to the first wireless communication assembly  500 . The first wireless communication assembly includes a first signal control chip  510  and a first antenna  520 . The first signal control chip  510  may control the first antenna  520  to transmit digital signals detected by the antenna assembly  120  electrically connected to the first antenna  520 , and receive digital signals sent from an external signal source, for example, the request instructions sent from the ground station. 
     As shown in  FIG. 4 , the second wireless communication assembly  400  and the power transmitter assembly  200  are integrated at a transmitter circuit board, which can be electrically connected to the power supply circuit board  210  of the power transmitter assembly  200  to supply power to the transmitter circuit board through the power supply circuit board  210 . The second wireless communication assembly  400  includes a second signal control chip  410  and a second antenna  420 . The second signal control chip  410  controls the second antenna  420  to receive digital signals sent from an external signal source, for example, to receive the digital signals sent from the first antenna  520 , and transmit digital signals, for example, to transmit the request instructions sent from the ground station. 
     To implement wireless communication between the first antenna  520  and the second antenna  420 , in one embodiment, the first antenna  520  may be a WIFI wireless antenna, and correspondingly, the second antenna  420  may also be a WIFI wireless antenna. 
     In another embodiment, the first antenna  520  may be a Bluetooth wireless antenna, and correspondingly, the second antenna  420  may also be a Bluetooth wireless antenna. 
     From a frequency band perspective, in one embodiment, the first antenna  520  may be a 2.4G wireless antenna, and correspondingly, the second antenna  420  may also be a 2.4G wireless antenna. 
     In another embodiment, the first antenna  520  may be a 5G wireless antenna, and correspondingly, the second antenna  420  may also be a 5G wireless antenna. 
     From a structure and shape perspective, in one embodiment, the first antenna  520  may be a plate antenna, and correspondingly, the second antenna  420  may also be a plate antenna. 
     With the above description, in the radar device shown in  FIG. 1 , the second wireless communication assembly  400  is fixedly mounted at the base, the first wireless communication assembly  500  is electrically connected to the antenna assembly, and there is a wireless communication connection therebetween. With such a communication method, since no cable is needed between the antenna assembly and the base to transmit the data signals, the limitation of the cable is eliminated, such that the electric motor can realize 360° omnidirectional rotation to drive the antenna assembly to realize 360° omnidirectional rotation to better detect the obstacles at different directions. 
     The present disclosure also provides a radar wireless rotating device, which can include a base, an antenna assembly, a power transmitter assembly, and a power receiver assembly. The antenna assembly can be arranged at the base and rotate around a rotation axis relative to the base. The power transmitter assembly can be configured to convert electric power into electromagnetic energy and transmit the electromagnetic energy. The power receiver assembly is electrically connected to the antenna assembly and rotates with the antenna assembly. The power receiver assembly can be configured to convert received electromagnetic energy into electric power and transmit the converted electric power to the antenna assembly. A structure, working principles, working processes, and realized working effects of the radar wireless rotating device are similar to those of the radar device described above, which are not repeated here. 
       FIG. 5  shows a UAV consistent with embodiments of the disclosure. The UAV includes a housing  610  and a radar device  620 . The radar device  620  is arranged at the housing  610 , and an antenna assembly (not shown in  FIG. 5 ) can establish a communication connection to a control system (not shown in  FIG. 5 ) of the UAV to transmit obstacle information detected by the antenna assembly to the control system. The control system controls flight of the UAV to avoid an obstacle in flight according to the received obstacle information. 
     For a structure, working principles, working processes, and working effects of the radar device  620 , reference may be made to relevant description above, which are not repeated here. 
     As shown in  FIG. 5 , the housing  610  includes a body  630  and stands  640  connected to two sides of the bottom of the body  630 . Further, the housing  610  includes arms  650  connected to sides of the body  630 . 
     In one embodiment, as shown in  FIG. 5 , the radar device  620  is fixedly connected to a stand  640 . 
     Those skilled in the art should understand that fixedly connecting the above-described radar device  620  to the stand  640  is merely an example. In practical applications, the radar device  620  may be fixedly connected to another part, such as an arm  650 , or a water tank. 
     Further, the UAV shown in  FIG. 5  may be a multi-rotor UAV, such as a quadrotor UAV or an octo-rotor UAV. A propeller  660  is connected to an end of the arm  650  distal from the body  630 . The propellers  660  provide flight power to the UAV. 
     In an embodiment, the UAV shown in  FIG. 5  may be an agricultural UAV, and the bottom of the UAV is provided with a container  670  configured to contain pesticides or seeds. A spreading mechanism (not shown in  FIG. 5 ) is provided at the container  670 . The spreading mechanism spreads the seeds contained in the container  670  to realize automatic agricultural operations. A spraying mechanism  680  is further provided at the end of the arm  650  distal from the body  630  and sprays the pesticide contained in the container  670  to realize automatic agricultural operations. 
     For device embodiments, since the device embodiments basically correspond to method embodiments, reference may be made to corresponding description of the method embodiments. The above-described device embodiments are merely illustrative, where a unit described as a separate component may or may not be physically separated, and a component displayed as a unit may or may not be a physical unit, i.e., may be located at one place or be distributed to a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve purpose of solutions of the embodiments. Those of ordinary skill in the art can understand and implement the solutions of the embodiments without any creative effort. 
     In the present disclosure, relational terms such as first and second are used merely to distinguish one entity or operation from another entity or operation and do not necessarily require or imply that such relationship or order exists between the entities or operations. The terms “including,” “comprising,” or any other variations cover a non-exclusive inclusion, such that a process, method, article, or device that includes a plurality of elements includes not only those elements but also other elements not listed, or elements that are inherent to such process, method, article, or device. In a situation without more limitations, an element associated with a phrase “include one . . . ” does not exclude presence of additional equivalent elements in the process, method, article, or device that includes the element. 
     The method and device provided by the embodiments of the present disclosure are described in detail above. The principles and implementations of the present disclosure are described with the specific examples. The description of the above embodiments is merely used to help to understand the methods and main ideas of the present disclosure. At the same time, for those of ordinary skill in the art, according to the ideas of the present disclosure, modifications may be made to specific embodiments and scope of applications. The present specification should not be construed as a limitation for the present disclosure.