Ball receiving apparatus and tennis robot

Abstract

The present application relates to a ball receiving apparatus and a tennis robot. The ball receiving apparatus comprises a base, at least three telescopic members, and a shielding member. The base has a first surface and an accommodating recess is recessed on the first surface; all of the telescopic members are arranged at intervals around the circumferential direction of the base, one end or side surface of all of the telescopic members are connected to the base, and the other end of all of the telescopic members is arranged to telescopically protrude from the first surface; and the shielding member is configured to be unfoldably and foldably connected between the telescopic members and the base and are used to enclose to form a ball receiving space, the ball receiving space having a ball entrance opening for a tennis ball to enter. The shielding member is used to block a tennis ball entering the ball receiving space. The ball receiving space communicates with the accommodating recess, so that the tennis ball falls into the accommodating recess after being blocked. According to the ball receiving apparatus provided in the present application, the telescopic members drive the shielding member to fold, and the shielding member is accommodated in the accommodating recess, so that the volume of the ball receiving apparatus can be effectively reduced, thereby facilitating storage and carrying by a user.

Description

ball-catching device and tennis robot

[0001] Cross-reference to related applications

[0002] This application claims Chinese Patent Application No. 2024230380973, filed on December 10, 2024, entitled "Serving Device and Tennis Robot"; Chinese Patent Application No. 2024118369264, filed on December 13, 2024, entitled "Tennis Robot and Control Method"; and Chinese Patent Application No. 2025104906475, filed on April 18, 2025, entitled "Receiving Device". This application incorporates, by reference, the priority of Chinese patent applications filed on July 4, 2025, with application number 202521415624X entitled "A Tennis Ball Receiving Device and a Tennis Robot" and application number 2025214092197 entitled "A Tennis Ball Receiving Device and a Tennis Robot", and some or all of the contents of the above priorities are incorporated herein by reference. Technical Field

[0003] This application relates to the field of sports equipment technology, and in particular to a ball-receiving device and a tennis robot. Background Technology

[0004] As people's living standards continue to improve, the public is paying increasing attention to sports and fitness. As a sport that alternates between aerobic and anaerobic exercise, tennis has benefits such as promoting the development of human functions, regulating emotions and boosting spirits, and promoting the physical and mental health of children and adolescents. More and more people are choosing to train in tennis to improve their fitness or enhance their athletic skills.

[0005] However, during tennis training, frequently retrieving the ball wastes a significant amount of energy for both athletes and coaches, leading to a decline in training quality and efficiency. Because tennis balls are launched at considerable heights, the catching device needs to meet corresponding height and dimensions to ensure a high success rate. This results in existing catching devices being bulky, difficult to carry, and inconvenient for users.

[0006] Application content

[0007] In view of this, the purpose of this application is to overcome the shortcomings of the prior art and provide a ball-receiving device and a tennis robot.

[0008] To achieve the above objectives, the first aspect of this application provides a ball-receiving device, comprising:

[0009] A base having a first surface, and a receiving groove being recessed on the first surface;

[0010] At least three telescopic members, all of which are circumferentially spaced around the base, with one end or side of each telescopic member connected to the base, and the other end of each telescopic member configured to retractably protrude from the first surface; and

[0011] A blocking member, configured to be unfoldable and foldable, is connected between each of the telescopic members and the base and serves to enclose a ball-receiving space having a ball-entry port for a tennis ball to enter; the blocking member is used to block a tennis ball entering the ball-receiving space; the ball-receiving space communicates with the receiving groove so that the tennis ball falls into the receiving groove after being blocked.

[0012] The second aspect of this application provides a tennis robot, including a ball-dropping component, a ball-serving component, and a ball-receiving device as described in any one of the above technical solutions;

[0013] The ball lowering assembly includes a ball lowering cylinder and a ball rotating module; the ball rotating module has multiple ball positions;

[0014] The ball-dropping assembly is used in conjunction with the ball-receiving device, which receives the tennis ball and transfers it to the ball-dropping tube, allowing the tennis ball served by the serving assembly to be retrieved by the ball-receiving device. Simultaneously, the retrieved tennis ball can fall onto multiple ball positions for re-serving by the serving assembly; and / or, the ball-receiving device receives the first tennis ball served by the user, and simultaneously, the tennis robot needs to launch a second tennis ball upon receiving the first tennis ball.

[0015] The ball-receiving device and tennis robot provided in this application, when all telescopic components are in the extended state, form a ball-receiving space with the base. A blocking component unfolds under the action of the telescopic components, covering the outside of the ball-receiving space, and an inlet is formed between any two adjacent telescopic components, connecting to the ball-receiving space. During tennis training, the tennis ball served by the user can enter the ball-receiving space through the inlet and be blocked by the blocking component, preventing the ball from falling out of the device. This allows for the centralized collection of tennis balls served by the user during training, facilitating retrieval and reducing wasted energy, thus improving training quality and efficiency. When all telescopic components are in the retracted state, the blocking component folds and is stored in the receiving slot under the action of the telescopic components. When the user needs to store and carry the ball-receiving device after training, all telescopic components are controlled to retract synchronously, causing the telescopic components to fold the blocking component and store it in the receiving slot. This effectively reduces the size of the ball-receiving device, making it easier for the user to store and carry. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 is a schematic diagram of the ball receiving device when the telescopic component is in the extended state in this application;

[0018] Figure 2 is a schematic diagram of the ball receiving device when the telescopic component is in the shortened state in this application;

[0019] Figure 3 is a structural schematic diagram of the first connector in this application;

[0020] Figure 4 is a cross-sectional structural diagram of the first connector in this application;

[0021] Figure 5 is a diagram showing the state of the tennis robot after the shielding component is deployed in one embodiment of this application;

[0022] Figure 6 is a diagram of the tennis robot after the shielding component is retracted in one embodiment of this application.

[0023] Figure 7 is a schematic diagram of the structure of the base of the ball receiving device in one embodiment of this application;

[0024] Figure 8 is a schematic diagram of the structure of the ball-serving device in one embodiment of this application;

[0025] Figure 9 is one of the structural schematic diagrams of the lower ball assembly in one embodiment of this application;

[0026] Figure 10 is a second schematic diagram of the lower ball assembly in one embodiment of this application;

[0027] Figure 11 is a schematic block diagram of the structure of a tennis robot according to an embodiment of this application;

[0028] Figure 12(a) is a schematic diagram of the longitudinal angle between the optical axes of two visible light cameras and the angle between the optical axes and the ground in one embodiment of this application;

[0029] Figure 12(b) is a schematic diagram of the longitudinal viewing angle range of two visible light cameras in space in one embodiment of this application;

[0030] Figure 13 is a schematic diagram of the lateral viewing angle range of two visible light cameras in space in one embodiment of this application;

[0031] Figure 14 is a schematic diagram of the angle between the viewing axes of two visible light cameras in one embodiment of this application;

[0032] Figure 15 is a flowchart illustrating the control method in one embodiment of this application;

[0033] Figure 16 is a schematic diagram of the process of obtaining the target predicted motion trajectory of the tennis ball to be caught based on a tennis ball image set and motion information in one embodiment of this application.

[0034] Figure 17 is a flowchart illustrating the process of controlling the movement of a tennis robot's mobile device based on a first tennis image set and corresponding motion information in an embodiment of this application, so as to obtain motion information and a second tennis image set during the movement of the mobile device.

[0035] Figure 18 is a flowchart illustrating the process of obtaining the target predicted motion trajectory of the tennis ball to be caught based on a first tennis ball image set, a second tennis ball image set, and motion information in one embodiment of this application.

[0036] Figure 19 is a schematic diagram of a tennis robot in one embodiment of this application during its movement.

[0037] Explanation of key component symbols: 100 - Mobile robot; 110 - Tennis robot body; 120 - Drive wheel; 131 - One of the two visible light cameras; 132 - The other of the two visible light cameras; 130 - Visual recognition module. 200-Ball receiving device; 20-Enclosure structure; 21-Base; 211-Receiving groove; 212-First connector; 2121-Main body; 2122-Connecting part; 2123-Mounting hole; 213-Second fixing part; 214-Guide part; 215-First side wall; 216-Second side wall; 217-Third side wall; 218-Fourth side wall; 22-Telescopic component; 221-First telescopic component; 222-Second telescopic component; 223-Third telescopic component; 224-Fourth telescopic component; 225-First fixing part; 23-Shielding component; 231-Ball receiving space; 232-Ball inlet; 233-First connecting edge; 234-Second connecting edge; 24-Elastic connector; 241-First elastic connector; 242-Second elastic connector; 25-Connecting ring; 26-Buffer component. 300-Serving device; 310-Ball placement assembly; 311-Ball placement tube; 3111-Tennis ball through hole; 312-Ball rotation module; 3121-Ball position; 3122-Ball rotation tube; 3123-Ball stop plate; 3124-Ball stop motor; 3125-Ball rotation motor; 320-First sensor assembly; 321-Second sensor assembly; 330-Serving assembly; 340-Controller; 350-Anti-shake firmware. Detailed Implementation

[0038] The embodiments of this application are described in detail below. Examples of these embodiments are shown 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 are only used to explain this application, and should not be construed as limiting this application.

[0039] In the description of this application, it should be understood that the terms "upper", "lower", "horizontal", "top", "bottom", "inner", "outer", "axial", "circumferential", 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 application 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 application.

[0040] 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 as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0041] In this application, unless otherwise expressly 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 abutment, 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 application according to the specific circumstances.

[0042] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. "Below," "under," and "below" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0043] As people's living standards continue to improve, the public is paying increasing attention to sports and fitness. As a sport that alternates between aerobic and anaerobic exercise, tennis has benefits such as promoting the development of human functions, regulating emotions and boosting spirits, and promoting the physical and mental health of children and adolescents. More and more people are choosing to train in tennis to improve their fitness or enhance their athletic skills.

[0044] However, during tennis training, frequently retrieving the ball wastes a significant amount of energy for both athletes and coaches, leading to a decline in training quality and efficiency. Because tennis balls are launched at considerable heights, the catching device needs to meet corresponding height and dimensions to ensure a high success rate. This results in existing catching devices being bulky, difficult to carry, and inconvenient for users.

[0045] Based on the above considerations, in order to solve the above problems, please refer to Figures 1 and 2. One or more embodiments of this application provide a ball-catching device 200. By setting a telescopic member 22 and a blocking member 23, the telescopic member 22 is extended and the blocking member 23 is unfolded to form a ball-catching space 231 for catching the ball. The ball-catching device 200 is reduced in size by controlling the telescopic member 22 to shorten and the blocking member 23 to fold, thereby making it easier for users to store and carry.

[0046] Specifically, in this application, referring to Figure 1, the ball-receiving device 200 includes a base 21, a blocking member 23, and at least three telescopic members 22. The base 21 has a first surface with a recessed receiving groove 211. All telescopic members 22 are circumferentially spaced around the base 21, and one end or side of each telescopic member 22 is connected to the base 21, while the other end of each telescopic member 22 is retractably protruding from the first surface. The blocking member 23 is configured to be unfoldable and foldable, connected between each telescopic member 22 and the base 21. When all telescopic members 22 are in their extended state, they and the base 21 enclose a ball-receiving space 231. The blocking member 23 unfolds under the action of the telescopic members 22, covering the outside of the ball-receiving space 231, and forming a ball-receiving opening 232 between any two adjacent telescopic members 22, communicating with the ball-receiving space 231.

[0047] For ease of understanding, this application describes an embodiment using a ball-receiving device 200 comprising four telescopic members 22 as an example. Specifically, when all four telescopic members 22 are in their extended state, the four telescopic members 22 and the base 21 enclose a ball-receiving space 231. Along the circumference of the base 21, an opening communicating with the ball-receiving space 231 is formed between every two adjacent telescopic members 22, i.e., the four telescopic members 22 are respectively configured to form four openings, and the four openings are defined as the first opening, the second opening, the third opening, and the fourth opening. Furthermore, a fifth opening communicating with the ball-receiving space 231 is also formed at the end of each of the four telescopic members 22 facing away from the base 21. A blocking member 23 is at least partially connected sequentially between the four telescopic members 22 along the circumference of the base 21, and the blocking member 23 sequentially covers any three consecutive adjacent openings between the first, second, third, and fourth openings along the circumference of the base 21; the uncovered opening corresponds to the ball-receiving opening 232; and the blocking member 23 also covers the fifth opening. Thus, when the ball receiving device 200 is used in tennis training, the tennis ball served by the user can enter the receiving space 231 through the ball inlet 232 and be blocked by the blocking member 23 to prevent the tennis ball from falling out of the ball receiving device 200. This allows the tennis ball served by the user during training to be collected in a centralized manner, making it convenient for the user to use. It can also effectively reduce the user's physical exertion and thus effectively improve the quality and efficiency of training.

[0048] In addition, please refer to Figure 2. When all telescopic members 22 are in the shortened state, the blocking member 23 is folded and at least partially stored in the receiving groove 211 under the action of the telescopic members 22.

[0049] Understandably, when the user needs to store and carry the ball receiving device 200 after completing training, by controlling all the telescopic parts 22 to shorten synchronously, the telescopic parts 22 drive the shielding parts 23 to fold and store the shielding parts 23 in the receiving slot 211. In this way, the volume of the ball receiving device 200 can be effectively reduced, making it easier for the user to store and carry.

[0050] Furthermore, the specific material of the shielding member 23 is not limited. Specifically, in the embodiments of this application, the shielding member 23 is made of an elastic material. For example: silicone, rubber (natural / synthetic), TPU (thermoplastic polyurethane), TPE (thermoplastic elastomer), etc.

[0051] Understandably, the shield 23, made of elastic material, possesses high elasticity. Thus, when the tennis ball enters the receiving space 231 and collides with the shield 23, the shield 23 effectively cushions and dissipates the tennis ball's kinetic energy, allowing it to fall relatively smoothly into the receiving slot 211 of the receiving space 231. Simultaneously, the shield 23, made of elastic material, is easy for users to fold and store, enhancing the user experience.

[0052] It should also be noted that the specific style of the shielding component 23 is not limited. For example, the shielding component 23 can be a mesh structure or a sheet structure.

[0053] Specifically, in the embodiments of this application, the shielding member 23 is a mesh structure. In this way, the mesh structure saves more materials, reduces weight and cost than solid structures such as sheet structures. Moreover, the mesh structure is lighter and easier to fold, transport and install.

[0054] When the ball receiving device 200 is used in actual training, when the ball hits the net surface, the impact force is dispersed to multiple nodes and lines of the mesh structure, avoiding material damage caused by concentrated force. In addition, the mesh structure can guide the ball to bounce in a specific direction or directly "catch" the ball through elastic deformation, which helps the tennis ball to fall more smoothly into the receiving groove 211 of the ball receiving space 231.

[0055] Furthermore, since tennis is mostly played outdoors, adapting to weather changes and improving the flexibility of the receiving device 200 are crucial. This application utilizes a mesh structure for the shielding member 23, allowing air to pass through and reducing the risk of wind pressure damage to the structure. Compared to solid structures such as sheet structures, this effectively reduces wind resistance, making it easier for users to operate.

[0056] In some embodiments, referring to Figures 1 and 2, the ball receiving device 200 further includes a buffer 26, which is fitted within the ball receiving space 231 and is configured to be expandable and foldable between each telescopic member 22 and the base 21.

[0057] When all telescopic components 22 are in the extended state, the buffer component 26 unfolds under the action of the telescopic components 22, and the buffer component 26 is positioned towards the inlet 232. When all telescopic components 22 are in the shortened state, the buffer component 26 folds and is stored in the receiving groove 211 under the action of the telescopic components 22.

[0058] Understandably, since the buffer 26 is positioned with its front facing the ball inlet 232, during tennis training, most of the tennis balls served by the user can enter the receiving space 231 through the ball inlet 232 and impact the buffer 26. The buffer 26 can cushion and eliminate the kinetic energy of the tennis ball, thereby preventing the tennis ball from falling out of the receiving device 200 and allowing the tennis ball to fall relatively smoothly into the receiving slot 211 of the receiving space 231.

[0059] Further, please refer to Figures 1 and 2. The specific material and style of the buffer 26 are not limited. Specifically, in the embodiment of this application, the buffer 26 is made of elastic material and has a mesh structure.

[0060] In some embodiments, please refer to Figures 1 and 2, each telescopic member 22 includes at least two telescopic segments, and the telescopic segments are sequentially slidably connected to each other.

[0061] It is understandable that each telescopic segment is a hollow tubular structure, and the segments are sequentially nested together, with a small gap between each nested segment to ensure free sliding, thus achieving the telescopic function of the telescopic component 22. Furthermore, each telescopic segment has a groove formed on its outer surface along its longitudinal direction, and when the segments are sequentially nested together, the grooves of each segment correspond to each other, thereby preventing circumferential rotation between nested segments.

[0062] In some embodiments, please refer to Figures 1 and 4, the base 21 also includes a mounting hole 2123 for inserting the telescopic member 22, the mounting hole 2123 extending at a predetermined angle A from one end near the bottom to the other end away from the bottom towards the outside of the base 21.

[0063] Understandably, when the telescopic rod is inserted into the mounting hole 2123 and is in the extended state, the end of the telescopic rod away from the base 21 is tilted outward in the direction away from the base 21 compared to the end of the telescopic rod closer to the base 21. Thus, the dimensions of the ball-receiving space 231 and the ball-scooping port 232 at the end away from the base 21 are larger than the dimensions at the end of the ball-receiving space 231 and the ball-scooping port 232 closer to the base 21, thereby ensuring that the ball-receiving device 200 has sufficient volume and that the ball-scooping port 232 of the ball-receiving device 200 can have a larger ball-receiving range, effectively improving ball-receiving efficiency and accuracy. At the same time, since the size of the base 21 can be kept within a small range, after shortening the telescopic rod and folding in the shield 23 and buffer 26, the ball-receiving device 200 can be effectively kept compact and easy to store.

[0064] It should be noted that the specific range of the preset angle A is not limited. However, in the specific embodiment of this application, the preset angle A satisfies the condition: 0°≤A≤45°.

[0065] Understandably, when the preset angle A is within the range of 0° to 45°, it ensures that the ball receiving device 200 has sufficient size and that the ball receiving port 232 of the ball receiving device 200 can have a larger ball receiving range, thereby effectively improving ball receiving efficiency and accuracy. At the same time, it also ensures the installation stability of structures such as the telescopic component 22.

[0066] In this application, the specific range of the preset angle A is obtained through experimental testing. The parameters and steps related to the experimental testing of the specific range of the preset angle A are conventional techniques for those skilled in the art and will not be described in detail here.

[0067] In some embodiments, please refer to Figures 1 and 3. The base 21 further includes a base body and a plurality of first connectors 212. The base body includes the first surface and a receiving groove 211. Each first connector 212 is disposed on the base body at circumferential intervals around the base 21, and each first connector 212 is provided with a mounting hole 2123.

[0068] Furthermore, each of the first connectors 212 includes a main body 2121 and a connecting portion 2122, the connecting portion 2122 protruding from the outside of the main body 2121 and connected to the base 21. The main body 2121 has a recessed mounting hole 2123 for inserting the telescopic member 22.

[0069] It is understandable that the specific connection method between the connecting part 2122 and the base 21 is not limited, such as threaded connection, adhesive bonding, snap-fit, etc.

[0070] Specifically, in the embodiments of this application, the connecting part 2122 and the base 21 are connected by bolts. Correspondingly, threaded holes are provided on both the connecting part 2122 and the base 21. When assembling the connecting part 2122 and the base 21, the threaded holes on the connecting part 2122 and the threaded holes on the base 21 need to be aligned, and then the bolts are used to achieve a fixed connection between the two.

[0071] It should also be noted that the specific connection method between the main body 2121 and the telescopic component 22 is not limited, such as: interference fit between the main body 2121 and the telescopic component 22, threaded connection between the main body 2121 and the telescopic component 22, etc.

[0072] Specifically, in this embodiment of the application, the main body 2121 and the telescopic member 22 are threadedly connected. Correspondingly, threaded holes are provided on both the main body 2121 and the telescopic member 22. When assembling the main body 2121 and the telescopic member 22, the telescopic member 22 needs to be inserted into the mounting hole 2123 first, and the telescopic member 22 needs to be rotated so that the threaded hole on the telescopic member 22 is aligned with the threaded hole on the main body 2121. Then, bolts are used to achieve a fixed connection between the two.

[0073] In some embodiments, please refer to Figures 1 and 2. The ball receiving device 200 further includes a plurality of first fixing members 225 and first mating members. Each first fixing member 225 is correspondingly disposed with each telescopic member 22 and is mated to the end of the telescopic member 22 facing away from the base 21. The first mating member is mated to the blocking member 23 and is connected to the first fixing member 225.

[0074] It is understood that the specific structure of the first fixing member 225 and the first mating member is not limited. For example, in this application, the first fixing member 225 is a fixing cover, the first mating member is a circular eyelet, the circular eyelet is fitted onto the blocking member 23, and the blocking member 23 is sleeved on the telescopic member 22 through the circular eyelet. The fixing cover is connected to the circular eyelet and the telescopic member 22 to achieve locking and fixing.

[0075] In some embodiments, please refer to Figures 1 and 2. The ball receiving device 200 further includes a second fixing member 213 and a second mating member. The second fixing member 213 is mated on the base 21, and the second mating member is mated on the shielding member 23. The second fixing member 213 is connected to the shielding member 23.

[0076] It is understood that the specific structure of the second fixing member 213 and the second mating member is not limited. For example, in this application, the second fixing member 213 is a hook and the second mating member is a mating hole. The connection between the shielding member 23 and the base 21 is achieved by hanging the hook in the mating hole.

[0077] In some embodiments, please refer to Figures 1 and 2, the ball receiving device 200 further includes a second connector and a third mating member. The second connector is movably sleeved on each telescopic rod, and the third mating member is mated to the blocking member 23, and the second connector and the third mating member are connected.

[0078] It is understood that the specific structures of the second connector and the third mating member are not limited. For example, in this application, the second connector is a self-locking open ring, and the third mating member is a circular eyelet. The circular eyelet is fitted onto the blocking member 23, and the self-locking open ring is sleeved on the telescopic member 22 and fastened to the circular eyelet. The second connector can also be an elastic connector 24. Thus, when the telescopic member 22 is in the extended state, the self-locking open ring, under the traction of the blocking member 23, will abut against the outer wall of the telescopic member 22, thereby fixing its position on the telescopic member 22. Simultaneously, the self-locking open ring can react on the blocking member 23 to enhance the structural stability of the blocking member 23.

[0079] To address the low success rate of current ball-catching devices, one embodiment provides a ball-catching device 200. The base 21 of the ball-catching device 200 is equipped with a barrier structure 20, which blocks the tennis ball, causing it to fall within the catching space 231. The top of the base 21 is also equipped with a guide part 214, which guides the falling tennis ball towards the inlet of the receiving groove 211, making it easier for it to enter the receiving groove 211. The tennis robot and ball-catching device 200 of this application will be described in detail below with reference to the accompanying drawings.

[0080] Referring to Figures 5 and 6, in some embodiments, the tennis robot includes a mobile robot 100 and a ball-catching device 200, wherein the ball-catching device 200 is mounted on the mobile robot 100 and moves with the mobile robot 100. In some embodiments, the mobile robot 100 has a vision recognition module 130 and drive wheels 120. Based on the tennis ball trajectory recognized by the vision recognition module 130, the mobile robot 100 can drive the ball-catching device 200 to move, so that the ball-catching device 200 catches the tennis ball.

[0081] In some embodiments, referring to Figures 5 to 7, the ball-catching device 200 includes a base 21 and a retaining structure 20. The base 21 has a receiving groove 211, and the top of the receiving groove 211 has a drop-in port for a tennis ball to fall into. The retaining structure 20 is arranged on the base 21, and the retaining structure 20 encloses a ball-catching space 231 above the receiving groove 211. The ball-catching space 231 has a ball-entry port 232 for the tennis ball to enter. The retaining structure 20 is used to block the tennis ball entering from the ball-entry port 232, so that the tennis ball falls into the receiving groove 211 after being blocked. It is easier to catch the tennis ball through the retaining structure 20, and the kinetic energy of the tennis ball is consumed after being blocked, making it easier for it to fall directly into the receiving groove 211 of the base 21.

[0082] To facilitate the smooth entry of the tennis ball into the receiving slot 211, a guide section 214 is provided at the top of the base 21. The guide section 214 is located at the drop-in point and extends upwards away from the center of the drop-in point. This guide section 214 guides the tennis ball from the receiving space 231 into the receiving slot 211, making it less likely for the ball to get stuck outside the drop-in point. Therefore, with the action of the blocking member 23 and the guide section 214, the tennis ball enters the receiving slot 211 more easily, improving the current technical problem of low ball-receiving success rate in the receiving device 200.

[0083] Regarding the guide portion 214, in some embodiments, please refer to Figure 7, the guide portion 214 is formed by bending. Specifically, the guide portion 214 and the base 21 are integrally bent, that is, the guide portion 214 is a folded edge that bends outward from the top of the base 21. Of course, in some other embodiments, the bent portion can also be formed and then fixed to the base 21 by welding, fasteners, or other methods.

[0084] To facilitate the processing of the guide portion 214, in some embodiments, referring to FIG7, the number of guide portions 214 is two or more, and each guide portion 214 is arranged at intervals along the outer periphery of the drop inlet. Compared with the continuous arrangement of guide portions 214, the arrangement of two or more guide portions 214 at intervals along the outer periphery of the drop inlet makes it easier to process them one by one and is less likely to cause stress concentration problems.

[0085] In some embodiments, referring to Figures 5 and 6, the base 21 includes at least three sidewalls connected in sequence, and the drop-in opening formed by each sidewall is a polygonal opening. Specifically, referring to Figures 5 to 7, the base 21 has four sidewalls, namely a first sidewall 215, a second sidewall 216, a third sidewall 217, and a fourth sidewall 218. Correspondingly, the drop-in opening is a quadrilateral opening. In some other embodiments, the base 21 may also have three or five sidewalls. Of course, the sidewalls of the base 21 may also be cylindrical, in which case the number of sidewalls is only one.

[0086] Since the connection between adjacent sidewalls forms a corner, to facilitate the processing of the guide portion 214, in some embodiments, referring to Figures 5 and 7, the guide portion 214 is connected to the top edge of the sidewall, and the gap formed between adjacent guide portions 214 is located above the connection between the adjacent sidewalls. This gap between adjacent guide portions 214 allows the guide portion 214 to avoid stress concentration areas, making it less prone to deformation and breakage during molding, thus lowering the requirements for the molding process.

[0087] Specifically, in some embodiments, please refer to Figure 5. The base 21 includes a first sidewall 215, and the ball inlet 232 is located above the first sidewall 215. The base 21 also includes other sidewalls, which are connected to the first sidewall 215 to form a receiving groove 211, and a guide portion 214 is located on the other sidewalls. This avoids the guide portion 214 from blocking the ball inlet 232, and the ball inlet 232 is larger, which is more conducive to the tennis ball entering the receiving space 231.

[0088] Specifically, regarding the remaining sidewalls and the first sidewall 215, in some embodiments, please refer to Figures 5 and 7. The remaining sidewalls include the second sidewall 216, the third sidewall 217, and the fourth sidewall 218. Guide portions 214 are connected to the second sidewall 216, the third sidewall 217, and the fourth sidewall 218. The guide portions 214 on the third sidewall 217 are arranged at intervals from the guide portions 214 on the other two sidewalls.

[0089] It should be noted that, in this embodiment, the first sidewall 215 refers to the portion of the sidewall of the base 21 located below the inlet 232. When the base 21 has a polygonal structure, there is a corner between the first sidewall 215 and the other sidewalls as a dividing feature. However, when the base 21 is cylindrical, the portion below the inlet 232 is the first sidewall 215, and the portion not below the inlet 232 is the other sidewall; there is no obvious structural dividing feature between the first sidewall 215 and the other sidewalls.

[0090] Regarding the shape of the guide portion 214, in some embodiments, please refer to Figures 5 and 7. The guide portion 214 is elongated and extends circumferentially along the drop inlet. The height direction of the guide portion 214 is the vertical direction, and the width direction is the horizontal extension direction. The circumferential dimension of the guide portion 214 gradually decreases from bottom to top. That is, in the vertical direction, the width dimension of the upper end of the guide portion 214 is smaller than the width dimension of the lower end, and the width dimension of the guide portion 214 gradually decreases from bottom to top. This makes the two corners of the upper end of the guide portion 214 obtuse angles, making it less likely to scratch the user. Of course, to further improve safety, the two corners of the upper end of the guide portion 214 are rounded.

[0091] Regarding the enclosure structure 20, it is understood that the enclosure structure 20 is arranged above the base 21, with the ball-scoring opening 232 facing the direction from which the tennis ball flies. To reduce the difficulty of catching the tennis ball, the ball-scoring opening 232 faces to the horizontal direction. In some embodiments, to prevent the tennis ball from easily bouncing out of the receiving space 231, the top of the receiving space 231 is also partially blocked and covered by the blocking member 23.

[0092] To reduce the rebound of the tennis ball after it is blocked by the enclosure structure 20, in some embodiments, referring to Figures 1 and 5, the enclosure structure 20 includes a telescopic member 22 and a blocking member 23 connected to the telescopic member 22. The telescopic member 22 is mounted on the base 21, and the blocking member 23 is used to block the tennis ball. After the blocking member 23 comes into contact with the tennis ball, it can better absorb the kinetic energy of the tennis ball, thus making the tennis ball less likely to rebound and fall in the receiving space 231.

[0093] Understandably, the blocking component 23 is prone to deformation under stress. This deformation can be either elastic or non-recoverable. For example, the blocking component 23 can be a mesh made of inelastic flexible rope or a mesh made of elastic flexible rope. Besides a mesh structure, the flexible stop can also be made of fabric. When the blocking component 23 is made of elastic material, it can be made of materials such as nylon, polyester, silicone, rubber (natural / synthetic), TPU (thermoplastic polyurethane), or TPE (thermoplastic elastomer).

[0094] In some embodiments, the shield 23 is an elastic mesh structure. Mesh structures use less material, are lighter, and are more convenient to use. When a tennis ball hits the shield 23, the impact force is distributed across multiple nodes and lines of the mesh structure, preventing material damage caused by concentrated force. The mesh structure directly "catches" the ball through elastic deformation, making the tennis ball less prone to bouncing and allowing it to fall more smoothly. Furthermore, the mesh structure allows air to pass through, reducing wind resistance and making it less likely to be blown over in windy weather.

[0095] Specifically, in some embodiments, referring to Figures 5 and 7, the lower end of the shielding member 23 is connected to the inner side of the side wall of the base 21. Specifically, the inner side of the side wall of the base 21 is provided with a connecting buckle, and the lower end of the shielding member 23 is connected to the connecting buckle via a connecting structure (such as a connecting rope, connecting strap, etc.). This way, after the shielding member 23 undergoes elastic deformation, a large gap is less likely to appear between the shielding member 23 and the base 21.

[0096] Furthermore, to better cushion the tennis ball, in some embodiments, referring to Figure 5, the telescopic member 22 includes a first telescopic member 221 and a second telescopic member 222, forming a ball-inlet 232 between the first telescopic member 221 and the second telescopic member 222. The enclosure structure 20 also includes an elastic connector 24, at least one of the first telescopic member 221 and the second telescopic member 222 being connected to the blocking member 23 via the elastic connector 24. Thus, after the tennis ball enters the receiving space 231 through the ball-inlet 232, it contacts the blocking member 23. The blocking member 23 deforms, pulling on the elastic connector 24. Under the pulling action of the blocking member 23, the elastic connector 24 elastically deforms, absorbing the kinetic energy of the tennis ball, thereby reducing the kinetic energy of the tennis ball and making it less likely for the tennis ball to bounce out of the receiving space 231. Specifically, in some embodiments, both the first telescopic member 221 and the second telescopic member 222 are connected to the blocking member 23 via the elastic connector 24.

[0097] Regarding the elastic connector 24, in some embodiments, the elastic connector 24 is an elastic pull cord. For ease of connection, a connecting ring 25 is connected to the shield 23, and the elastic pull cord is connected to the connecting ring 25. In some other embodiments, the elastic connector 24 may also be a spring in addition to an elastic pull cord.

[0098] For ease of storage, in some embodiments, please refer to Figures 5 and 6, the telescopic member 22 can extend to allow the enclosure structure 20 to unfold, forming a ball-receiving space 231 inside the enclosure structure 20. The telescopic member 22 can shorten to allow the enclosure structure 20 to fold up, reducing the volume of the enclosure structure 20 and facilitating storage.

[0099] Therefore, before using the ball-catching device 200 to catch a ball, each telescopic member 22 needs to be extended to unfold the enclosure structure 20. When not in use, the telescopic members 22 need to be retracted to fold up the enclosure structure 20. At this time, part of the enclosure structure 20 can be stored in the receiving slot 211. After the enclosure structure 20 is folded up, its volume is smaller and easier for the user to carry. Of course, in some other embodiments, the telescopic member 22 can also be a fixed-length rod, in which case the telescopic member 22 cannot extend or retract.

[0100] The number of telescopic components 22 can be set as needed. For example, in some embodiments, referring to Figures 5 and 6, there are four telescopic components 22, which are respectively fixed at the connection points of adjacent sidewalls of the base 21. The base 21 is provided with mounting members (i.e., first connecting members 212) for mounting the telescopic components 22. In some embodiments, the mounting members have mounting holes 2123, which can be threaded holes, and the telescopic components 22 are screwed into the mounting holes 2123. The mounting holes 2123 can also be insertion holes, and the telescopic components 22 are directly inserted into the mounting holes 2123.

[0101] In some other embodiments, the number of telescopic members 22 may also be two, namely the first telescopic member 221 and the second telescopic member 222. Of course, in some other embodiments, the number of telescopic members 22 may also be three, five, or other feasible numbers.

[0102] In some embodiments, referring to Figures 5 and 6, the ball-receiving device 200 includes a base 21, a telescopic member 22, and a blocking member 23. The base 21 has a receiving groove 211, with an opening at the top for a tennis ball to fall into. The telescopic member 22 is mounted on the base 21, and the blocking member 23 is connected to the telescopic member 22 and forms a ball-receiving space 231. The ball-receiving space 231 has a ball-entry opening 232 for the tennis ball to enter. The blocking member 23 is used to block the tennis ball from entering the ball-receiving space 231. The ball-receiving space 231 communicates with the receiving groove 211, allowing the tennis ball to fall into the receiving groove 211 after being blocked. After entering the ball-receiving space 231 through the ball-entry opening 232, the tennis ball is stopped by the blocking member 23. The blocking member 23 absorbs the kinetic energy of the tennis ball, making it less likely for the tennis ball to bounce out of the ball-receiving space 231.

[0103] The ball-receiving device 200 also includes an elastic connector 24, which connects the blocking member 23 and the telescopic member 22. Because the elastic connector 24 connects the blocking member 23 and the telescopic member 22, after the tennis ball impacts the blocking member 23, the part connecting the blocking member 23 and the elastic connector 24 is subjected to a pulling force and can move relative to the telescopic member 22. The blocking member 23 can pull the elastic connector 24, causing the elastic connector 24 to deform elastically, further absorbing the kinetic energy of the tennis ball, making it less likely for the tennis ball to bounce back.

[0104] Understandably, the shielding component 23 is prone to deformation under stress. This deformation can be either elastic or non-recoverable. For example, the shielding component 23 can be a net made of flexible rope without elasticity, or it can be a net made of flexible rope with elasticity. In addition to a mesh structure, the shielding component 23 can also be made of fabric.

[0105] In some embodiments, the shield 23 is an elastic mesh or elastic fabric, so that the shield 23 can also elastically deform and absorb the kinetic energy of the tennis ball under the impact of the tennis ball. When the shield 23 is made of an elastic material, it can be made of materials such as nylon, polyester, silicone, rubber (natural / synthetic), TPU (thermoplastic polyurethane), TPE (thermoplastic elastomer), etc.

[0106] When the shield 23 adopts an elastic mesh structure, less material is used, resulting in a lighter weight and greater ease of use. When a tennis ball impacts the shield 23, the impact force is distributed across multiple nodes and lines of the mesh structure, preventing material damage caused by concentrated force. The mesh structure directly "catches" the ball through elastic deformation, making the tennis ball less prone to bouncing and allowing it to fall more smoothly. Furthermore, the mesh structure allows air to pass through, reducing wind resistance and making it less likely to be blown over in windy weather.

[0107] As can be understood, referring to Figure 5, the receiving space 231 is located above the receiving groove 211, and the ball inlet 232 faces the direction from which the tennis ball flies. To reduce the difficulty of catching the tennis ball, the ball inlet 232 faces to the horizontal direction. In some embodiments, referring to Figures 5 and 6, in order to prevent the tennis ball from easily popping out of the receiving space 231, the top of the receiving space 231 is also covered by the blocking member 23.

[0108] It should be noted that the elastic connector 24 in this application connects the telescopic member 22 and the shielding member 23, including but not limited to the telescopic member 22 and the shielding member 23 being connected solely by the elastic connector 24. For example, in some embodiments, when there are multiple telescopic members 22, some telescopic members 22 and the shielding member 23 are connected by the elastic connector 24, while others are connected by non-elastic components. Furthermore, in some embodiments, the same telescopic member 22 may be connected to the shielding member 23 at some locations via the elastic connector 24, and at other locations via non-elastic components. Specifically, in one embodiment, the upper end of the telescopic member 22 is connected to the shielding member 23 via a non-elastic component, while the middle and lower parts of the telescopic member 22 are connected to the shielding member 23 via the elastic connector 24. It is understood that the non-elastic components described in the embodiments of this application include, but are not limited to, rigid components, flexible components, such as cable ties or rigid straps that do not deform elastically.

[0109] To facilitate connection with the shielding member 23, in some embodiments, referring to Figure 5, the ball receiving device 200 further includes a connecting ring 25 connected to the shielding member 23, and the elastic connecting member 24 is connected to the shielding member 23 through the connecting ring 25. Of course, in some other embodiments, the shielding member 23 may also have a through hole, through which the elastic connecting member 24 passes and connects to the shielding member 23. In some embodiments, the connecting ring 25 penetrates the shielding member 23.

[0110] In some embodiments, the elastic connector 24 is an elastic cord. In some other embodiments, the elastic connector 24 may also be a spring.

[0111] Regarding the structure of the telescopic member 22, in some embodiments, please refer to Figure 5. The telescopic member 22 includes a first telescopic member 221 and a second telescopic member 222, forming a ball-scoring opening 232 between the first telescopic member 221 and the second telescopic member 222. Both the first telescopic member 221 and the second telescopic member 222 are connected to the blocking member 23 via elastic connectors 24. Since the first telescopic member 221 and the second telescopic member 222 are located at the ball-scoring opening 232, after the tennis ball enters the receiving space 231, it is easier to pull the portion of the blocking member 23 connected to the ball-scoring opening 232. The elastic connectors 24 connect the first telescopic member 221 to the blocking member 23 and the second telescopic member 222 to the blocking member 23, allowing the elastic connectors 24 to better absorb the kinetic energy of the tennis ball through elastic deformation, thus reducing the rebound of the tennis ball.

[0112] Furthermore, in some embodiments, referring to FIG5, the elastic connector 24 includes a first elastic connector 241 connected to the first telescopic member 221. The number of first elastic connectors 241 is two or more. The shielding member 23 has a first connecting edge 233, and each first elastic connector 241 is connected to the first connecting edge 233 and arranged at intervals along the first connecting edge 233. The interval arrangement of the first elastic connectors 241 along the first connecting edge 233 allows for more uniform force distribution on the first connecting edge 233 of the shielding member 23, avoiding damage caused by excessive local force, and making the connection with the first telescopic member 221 more reliable.

[0113] Similarly, in some embodiments, please refer to FIG5, the elastic connector 24 includes a second elastic connector 242 connected to the second telescopic member 222, the number of the second elastic connector 242 is two or more, the shielding member 23 has a second connecting edge 234, and each second elastic connector 242 is connected to the second connecting edge 234 and arranged at intervals along the second connecting edge 234.

[0114] Regarding the number of telescopic components 22, in some embodiments, please refer to Figure 5, the number of telescopic components 22 is four. In some other embodiments, the number of telescopic components 22 may also be two, namely the first telescopic component 221 and the second telescopic component 222. Of course, in some other embodiments, the number of telescopic components 22 may also be three, five, or other feasible numbers.

[0115] Furthermore, in some embodiments, referring to Figure 5, the telescopic member 22 further includes a third telescopic member 223 and a fourth telescopic member 224. The upper end of the third telescopic member 223 is connected to the blocking member 23, and the lower end of the third telescopic member 223 is mounted on the base 21. The upper end of the fourth telescopic member 224 is connected to the blocking member 23, and the lower end of the fourth telescopic member 224 is mounted on the base 21. The first telescopic member 221, the second telescopic member 222, the third telescopic member 223, and the fourth telescopic member 224 are arranged at intervals along the circumference of the base 21. In this way, the ball-receiving space 231 supported by the first telescopic member 221, the second telescopic member 222, the third telescopic member 223, and the fourth telescopic member 224 has better stability. In some embodiments, the third telescopic member 223 is connected to the shield 23 only at its upper end, and the fourth telescopic member 224 is connected to the shield 23 only at its upper end. This allows the shield 23 to have a larger range of motion when the tennis ball impacts the shield 23, enabling it to adapt to impacts from multiple angles of the tennis ball.

[0116] In some other embodiments, when the telescopic member 22 does not require extension or retraction, the telescopic member 22 can be a support frame structure formed by connecting multiple support rods, in which case the number of telescopic members 22 can be only one.

[0117] For ease of storage, in some embodiments, referring to Figures 5 and 6, the telescopic member 22 extends or retracts to expand or retract the blocking member 23. The telescopic member 22, by extending, allows the blocking member 23 to expand, creating a ball-receiving space 231 inside. The telescopic member 22, by shortening, allows the blocking member 23 to retract, reducing the space occupied by the blocking member 23 and facilitating storage.

[0118] Therefore, before using the tennis ball receiving device 200 to receive a ball, each telescopic member 22 needs to be extended and the blocking member 23 needs to be unfolded. When not in use, the telescopic members 22 need to be retracted and the blocking member 23 needs to be folded up. At this time, part of the blocking member 23 can be stored in the receiving slot 211. After the blocking member 23 is folded up, the volume is smaller and easier for the user to carry. Of course, in embodiments that aim to achieve a high ball receiving success rate, the telescopic member 22 can also be a fixed-length rod, in which case the telescopic member 22 cannot be extended or retracted.

[0119] Specifically, in some embodiments, referring to Figure 5, the base 21 is provided with a mounting member (i.e., a first connecting member 212) for mounting the telescopic member 22. In some embodiments, the mounting member has a mounting hole 2123, which can be a threaded hole, in which the telescopic member 22 is screwed and installed. The mounting hole 2123 can also be an insertion hole, in which the telescopic member 22 is directly inserted.

[0120] In some embodiments, referring to Figures 5 and 7, the lower end of the shielding member 23 is connected to the inner side of the side wall of the base 21, that is, installed on the inner wall of the receiving groove 211. Specifically, a connecting buckle (i.e., a second fixing member 213) is provided on the inner side of the side wall of the base 21, and the lower end of the shielding member 23 is connected to the connecting buckle through a connecting structure (such as a connecting rope, connecting strap, etc.). In this way, after the shielding member 23 elastically deforms, it is not easy for an excessively large gap to appear between the shielding member 23 and the base 21.

[0121] To make it easier for the tennis ball to enter the receiving slot 211 from the receiving space 231, in some embodiments, referring to Figures 5 and 7, a guide portion 214 is provided on the top of the base 21. The guide portion 214 is located at the drop-in port and extends from bottom to top in a direction away from the center of the drop-in port. In this way, the guide portion 214 can guide the tennis ball from the receiving space 231 into the receiving slot 211, and the tennis ball is less likely to get stuck on the outside of the drop-in port.

[0122] Regarding the guide portion 214, in some embodiments, please refer to Figure 7, the guide portion 214 is formed by bending. Specifically, the guide portion 214 and the base 21 are integrally bent, that is, the guide portion 214 is a folded edge that bends outward from the top of the base 21. Of course, in some other embodiments, the bent portion can also be formed and then fixed to the base 21 by welding, fasteners, or other methods.

[0123] To facilitate the processing of the guide portion 214, in some embodiments, referring to FIG7, the number of guide portions 214 is two or more, and each guide portion 214 is arranged at intervals along the outer periphery of the drop inlet. Compared with the continuous arrangement of guide portions 214, the arrangement of two or more guide portions 214 at intervals along the outer periphery of the drop inlet makes it easier to process them one by one and is less likely to cause stress concentration problems.

[0124] In some embodiments, referring to Figures 5 and 7, the base 21 includes at least three sidewalls connected in sequence, and the drop-in opening formed by each sidewall is a polygonal opening. Specifically, referring to Figures 5 to 7, the base 21 has four sidewalls, namely a first sidewall 215, a second sidewall 216, a third sidewall 217, and a fourth sidewall 218. Correspondingly, the drop-in opening is a quadrilateral opening. In some other embodiments, the base 21 may also have three or five sidewalls. Of course, the sidewalls of the base 21 may also be cylindrical, in which case the number of sidewalls is only one.

[0125] Since the connection between adjacent sidewalls forms a corner, to facilitate the processing of the guide portion 214, in some embodiments, referring to Figures 5 and 7, the guide portion 214 is connected to the top edge of the sidewall, and the gap formed between adjacent guide portions 214 is located above the connection between the adjacent sidewalls. This gap between adjacent guide portions 214 allows the guide portion 214 to avoid stress concentration areas, making it less prone to deformation and breakage during molding, thus lowering the requirements for the molding process.

[0126] Specifically, in some embodiments, please refer to Figure 5. The base 21 includes a first sidewall 215, and a ball inlet 232 is located above the first sidewall 215. The base 21 also includes other sidewalls, which are connected to the first sidewall 215 to form a receiving groove 211. A guide portion 214 is located on the other sidewalls. This avoids the guide portion 214 from obstructing the ball inlet 232, and the larger size of the ball inlet 232 makes it easier for the tennis ball to enter the receiving space 231.

[0127] Specifically, please refer to Figures 5 and 7. Guide portions 214 are connected to the second side wall 216, the third side wall 217 and the fourth side wall 218. The guide portions 214 on the third side wall 217 are arranged at intervals with the guide portions 214 on the other two side walls.

[0128] Regarding the shape of the guide portion 214, in some embodiments, please refer to Figures 5 and 7. The guide portion 214 is elongated and extends circumferentially along the drop inlet. The height direction of the guide portion 214 is the vertical direction, and the width direction is the horizontal extension direction. In the vertical direction, the width of the upper end of the guide portion 214 is smaller than the width of the lower end, and the width of the guide portion 214 gradually decreases from bottom to top. This makes the two corners of the upper end of the guide portion 214 obtuse angles, making it less likely to scratch the user. Of course, to further improve safety, the two corners of the upper end of the guide portion 214 are rounded.

[0129] This application also provides a tennis robot that can play against a user. For example, the tennis robot includes a receiving device 200 and a serving device 300. The receiving device 200 receives a first tennis ball served by the user. Simultaneously with receiving the first tennis ball, the tennis robot needs to launch a second tennis ball, thus enabling a tennis exchange with the user. Existing tennis robots struggle to launch the second tennis ball in a timely manner and cannot accurately control the timing of the serve.

[0130] Based on this, this application provides a tennis robot. Referring to Figures 8 and 9, Figure 8 shows a structural schematic diagram of the serving device in this embodiment; Figure 9 shows one of the structural schematic diagrams of the ball-dropping assembly in this embodiment. Figure 9 illustrates that the ball-dropping tube 311 includes four ball positions 3121 as an example. In other embodiments, the number of ball positions 3121 in the ball-dropping tube 311 may be other than the examples in the accompanying drawings.

[0131] The serving device 300 in this embodiment includes a ball-dropping assembly 310, a first sensing assembly 320, a serving assembly 330, and a controller 340. The ball-dropping assembly 310 includes a ball-dropping tube 311 and a ball-spinning module 312. The bottom of the ball-dropping tube 311 has a tennis ball through-hole 3111. The ball-spinning module 312 is embedded in the ball-dropping tube 311 and has multiple ball positions 3121. The first sensing assembly 320 is used to send a signal to the controller 340 when a tennis ball is detected at a target ball position. 0 outputs a first detection signal; the target ball position 3121 is any one of multiple ball positions 3121; the serving assembly 330 is used to launch the falling tennis ball when a tennis ball is falling through the tennis ball hole 3111; the controller 340 is electrically connected to the first sensing assembly 320 and the ball spinning module 312, and is used to control the ball spinning module 312 to let the tennis ball on the target ball position 3121 fall through the tennis ball hole 3111 to the serving assembly 330 when the first detection signal is received.

[0132] The ball-dropping assembly 310 can be used in conjunction with other devices to drop a tennis ball to the serving assembly 330. For example, the ball-dropping assembly 310 can be used in conjunction with the receiving device 200, which transmits the received ball to the ball-dropping tube 311, allowing the tennis ball served by the serving assembly 330 to be retrieved by the receiving device 200. Simultaneously, the retrieved tennis ball can fall onto multiple ball positions 3121 of the ball-spinning module 312, allowing it to be sent again by the serving assembly 330, thus achieving the recycling of the tennis ball.

[0133] The first sensing component 320 can be positioned at any location capable of detecting whether a tennis ball is in the target ball position. For example, the first sensing component 320 can be located at the bottom of the ball-spinning module 312 and correspond to the position of the target ball position.

[0134] In this embodiment, after the controller 340 confirms that there is a tennis ball at the target ball position through the first detection signal, it controls the ball-rotating module 312 to drop the tennis ball at the target ball position through the tennis ball through hole 3111 to the serving assembly 330, thereby achieving precise control of the serving timing and avoiding the instability of the serving time caused by the ball-rotating module 312 rotating on its own to drop the tennis ball at position 3121 through the tennis ball through hole 3111.

[0135] In one embodiment, the controller 340 can also be used to control the mobile device (i.e., drive wheel 120) of the tennis robot to move to the target position. When it moves to the target position, it drives the first sensing component 320 to detect the target ball position. When it receives the first detection signal, it controls the ball-spinning module 312 to drop the tennis ball on the target position through the tennis ball through hole 3111 to the serving component 330.

[0136] For example, the target position refers to the position where the tennis robot can catch the tennis ball. When the robot moves to the target position, the controller 340 will receive the corresponding electrical signal. At this time, the first gating circuit configured in the controller 340 will select the connection between the first driving circuit (which can be the circuit inside the controller 340 or the circuit connected to the gating circuit in the controller 340) and the first sensing component 320 under the action of the corresponding electrical signal. The first driving circuit sends the first driving electrical signal to the first sensing component 320 through the first gating circuit to drive the first sensing component 320 to start working and realize the detection of the target ball position. Upon receiving the first detection signal, the second selection circuit built into the controller 340, under the action of the first detection signal, selects the connection between the second drive circuit (which can be a circuit inside the controller 340 or a circuit externally connected to the selection circuit in the controller 340) and the ball-spinning module 312. The second drive circuit sends a second drive signal to the ball-spinning module 312 through the second selection circuit to drive the ball-spinning module 312 to start working, controlling the ball-spinning module 312 to drop the tennis ball on the target ball position through the tennis ball through hole 3111 to the serving assembly 330. In this embodiment, it can ensure that the serving device 300 serves the tennis ball at the same time as receiving the ball, realizing controllable serving and improving the immediacy of serving.

[0137] In one embodiment, the controller 340 is further configured to, upon receiving a first detection signal and an externally input serve signal, control the ball-spinning module 312 to drop the tennis ball on the target ball position through the tennis ball through-hole 3111 to the serve assembly 330.

[0138] The serve signal is used to indicate that a tennis ball needs to be served to the opponent. At the same time, the first detection signal indicates that there is a tennis ball at the target position, thus meeting the serve conditions. At this time, the controller 340 controls the ball-spinning module 312 to drop the tennis ball on the target position through the tennis ball through hole 3111 to the serve assembly 330, which can realize on-demand serve and improve the playing experience.

[0139] In one embodiment, the ball-spinning module 312 includes a ball-spinning motor 3125 and a ball-spinning cylinder 3122. The ball-spinning motor 3125 is electrically connected to the ball-spinning cylinder 3122 and the controller 340, respectively. The ball-spinning motor 3125 is used to control the rotation of the ball-spinning cylinder 3122 so that the positions of a plurality of ball positions 3121 in the ball-spinning cylinder 3122 relative to the tennis ball through-hole 3111 change.

[0140] The controller 340 is used to drive the ball-rotating motor 3125 to control the ball-rotating cylinder 3122 to rotate when it receives the first detection signal, so that the position of the target ball position corresponds to the position of the tennis ball through hole 3111, so that the tennis ball on the target ball position falls to the serving assembly 330 through the tennis ball through hole 3111.

[0141] The ball motor 3125 can be any structure capable of providing a rotational power source for the ball cylinder 3122. For example, the ball motor 3125 can be a ball servo motor. In practical applications, the type of ball motor 3125 can be flexibly configured according to actual needs, and is not limited to the above example.

[0142] In this embodiment, the controller 340 controls the rotation of the ball-rotating cylinder 3122 by driving the ball-rotating motor 3125, thereby rotating the target ball position to the position corresponding to the tennis ball through hole 3111, so as to achieve accurate serving of the tennis ball on the target ball position.

[0143] Specifically, the controller 340 can flexibly select different drive circuits to control the rotation angle of the ball-rotating cylinder 3122 by the drive ball-rotating motor 3125. For example, the controller 340 outputs a drive signal of a preset frequency to the ball-rotating motor 3125, enabling the motor to control the ball-rotating cylinder 3122 to rotate by a preset angle within a time period corresponding to the preset frequency. This preset angle can be the angle corresponding to rotating one ball position 3121. For example, if the target ball position is adjacent to the tennis ball through-hole 3111, then within one frequency cycle, the drive signal is output to drive the ball-rotating motor 3125 to control the ball-rotating cylinder 3122 to rotate by the preset angle.

[0144] In another example, a Hall sensor can be installed in the ball-rotating cylinder 3122 to detect the angle of the target ball relative to the tennis ball hole 3111 in real time. This angle is represented by an angle detection electrical signal. A comparator compares this angle detection electrical signal with a target electrical signal, which indicates that the target ball is located at the position corresponding to the tennis ball hole 3111. When the angle detection electrical signal is less than or equal to the target electrical signal, it indicates that the target ball has rotated to the position corresponding to the tennis ball hole 3111, and the controller 340 stops driving the ball-rotating motor 3125, thereby controlling the tennis ball on the target ball position to fall accurately. In practical applications, the controller 340 can drive the ball-rotating motor 3125 to control the rotation angle of the ball-rotating cylinder 3122 in other ways, and is not limited to the above example.

[0145] In one embodiment, the target ball position includes ball position 3121 adjacent to the ball position corresponding to the tennis ball through hole 3111.

[0146] In this embodiment, the target ball position is adjacent to the ball position 3121 corresponding to the tennis ball through hole 3111, which can reduce the rotation angle of the ball rotating tube 3122 and drop the tennis ball on the ball rotating tube 3122 to the serving assembly 330 more quickly, thereby increasing the serving speed.

[0147] In one embodiment, referring to Figures 9 and 10, Figure 10 shows a second schematic diagram of the lower ball assembly.

[0148] The ball-spinning module 312 in this embodiment includes a ball-spinning cylinder 3122, a ball-blocking plate 3123, and a ball-blocking motor 3124. The ball-spinning cylinder 3122 is provided with multiple ball positions 3121. The rotating end of the ball-blocking plate 3123 is connected to the ball-blocking motor 3124, and the ball-blocking plate 3123 is located between the tennis ball through hole 3111 and the ball-serving assembly 330. The first sensing assembly 320 is located on the side of the ball-blocking plate 3123 facing away from the tennis ball through hole 3111.

[0149] Among them, the target ball position includes the ball position 3121 corresponding to the position of the ball blocking plate 3123.

[0150] The controller 340 is used to drive the ball-blocking motor 3124 to rotate the ball-blocking plate 3123 around the rotating end when it receives the first detection signal, so that the tennis ball on the target ball position falls through the tennis ball through hole 3111 to the serving assembly 330.

[0151] In this embodiment, the timing of the tennis ball's descent from the target position is limited by the ball-blocking plate 3123. When the first sensing component 320 detects a tennis ball in the target position on the ball-blocking plate 3123, the ball-blocking motor 3124 is driven to control the ball-blocking plate 3123 to rotate around its rotating end in its plane, thereby releasing the tennis ball from the target position. This allows for precise control of the serving timing and enables rapid serves.

[0152] In one embodiment, the first sensing component 320 is further configured to output a second detection signal when there is no tennis ball on the ball position 3121 corresponding to the position of the ball deflector 3123; the ball rotation module 312 also includes a ball rotation motor 3125, which is connected to the ball rotation cylinder 3122 and the controller 340.

[0153] The controller 340 is used to drive the ball-rotating motor 3125 to control the ball-rotating cylinder 3122 to rotate when a second detection signal is received, until there is a tennis ball at the ball position 3121 corresponding to the position of the ball-blocking plate 3123.

[0154] The second detection signal can be an electrical signal with a different level than the first detection signal. For example, if the second detection signal is a low-level signal, the first detection signal can be a high-level signal. Conversely, if the second detection signal is a high-level signal, the first detection signal can be a low-level signal.

[0155] In this embodiment, when the first sensing component 320 detects that there is no tennis ball at the target ball position corresponding to the ball blocking plate 3123, the controller 340 drives the ball rotating motor 3125 to control the ball rotating cylinder 3122 to rotate until there is a tennis ball at the ball position corresponding to the ball blocking plate 3123. At this time, the first sensing component 320 outputs the first detection signal, and the controller 340 drives the ball blocking motor 3124 to control the ball blocking plate 3123 to rotate, so that the tennis ball on the ball position 3121 corresponding to the ball blocking plate 3123 falls to the serving component 330.

[0156] In one embodiment, the ball-spinning module 312 further includes a ball-limiting plate disposed on the side of the lower ball tube 311 facing away from the ball-serving assembly 330. The position of the ball-limiting plate corresponds to the position of the tennis ball through hole 3111, and is used to limit the number of tennis balls on the ball position 3121 corresponding to the position of the tennis ball through hole 3111 to one.

[0157] The height of the ball-limiting plate from the bottom of the lower ball tube 311 is slightly greater than the diameter of the tennis ball. This height can be flexibly set as needed, and is not limited in this embodiment. Based on this, it can be ensured that the tennis balls at other ball positions 3121 have sufficient height to rotate to the position corresponding to the tennis ball through-hole 3111.

[0158] In this embodiment, the number of tennis balls passing through the tennis ball through hole 3111 is limited by the ball limiting plate to prevent multiple tennis balls from falling at the same time, which would result in multiple tennis balls being launched at once and affect the playing experience.

[0159] In one embodiment, the first sensing component 320 includes any one of an infrared sensor, a gravity sensor, and an ultrasonic sensor.

[0160] In this embodiment, the detection of whether the tennis ball is in the target position can be achieved by using any one of the infrared sensor, gravity sensor, and ultrasonic sensor, ensuring the feasibility and accuracy of the detection.

[0161] In practical applications, the first sensing component 320 can also be other sensors or sensing circuits, and is not limited to the examples above.

[0162] In one embodiment, the ball-serving device 300 further includes a buffer structure disposed on the side of the lower ball tube 311 opposite to the ball-serving assembly 330, for buffering the tennis ball falling into the lower ball tube 311.

[0163] The cushioning structure can be made of any material capable of slowing down the falling speed of the tennis ball. For example, the cushioning structure can be made of foam, but is not limited to this.

[0164] In this embodiment, by providing a buffer structure on the side of the lower ball tube 311 facing away from the ball serving assembly 330, the speed at which the tennis ball falls freely when the lower ball tube 311 receives the tennis ball can be limited, the vibration of the tennis ball on the lower ball tube 311 can be reduced, and the tennis ball can be ensured to fall accurately onto the ball spinning module 312, thereby improving the consistency of the serving position and timing.

[0165] In one embodiment, the difference between the diameter of the tennis ball through-hole 3111 and the diameter of a single tennis ball satisfies a preset condition, so that the tennis ball through-hole 3111 can pass through a single tennis ball.

[0166] The preset condition can be understood as the condition when a tennis ball just passes through. In practical applications, the difference between the diameter of the tennis ball through-hole 3111 and the diameter of a single tennis ball can be flexibly set as needed. For example, the difference between the diameter of the tennis ball through-hole 3111 and the diameter of a single tennis ball can be less than or equal to 5mm, but it is not limited to this.

[0167] In this embodiment, the difference between the diameter of the tennis ball through hole 3111 and the diameter of a single tennis ball meets a preset condition, so that the tennis ball through hole 3111 can pass through a single tennis ball, avoiding multiple tennis balls falling at the same time, which would cause the serving assembly 330 to jam, or the serving assembly 330 to serve multiple tennis balls at once, affecting the playing experience.

[0168] Multiple visible light cameras are set up at preset positions on the court to capture the trajectory of the tennis ball in real time during the match. The controller in the tennis robot then controls the moving device (i.e., drive wheel 120) to move to the predicted receiving position based on the trajectory of the tennis ball to receive the ball.

[0169] However, the above approach reduces the adaptability of the tennis robot. The tennis robot can only receive the ball in locations equipped with visible light cameras capable of transmitting data to its controller.

[0170] Based on this, the inventors provided an alternative solution: without changing the current structure of the tennis robot, simply placing a visible light camera on it, thus solving the limitation on the adaptability of the tennis robot caused by the placement of the visible light camera. However, because the tennis robot needs to move constantly during a match to ensure timely reception of the tennis ball, the position and orientation of the visible light camera on the robot are constantly changing. Even when capturing the tennis ball at the same location, different images will be obtained, making it impossible to determine the position of the tennis ball on the court. This poses a significant challenge to predicting the trajectory and landing point of the tennis ball.

[0171] Based on the above research, in one embodiment, this application provides a tennis robot. Referring to FIG11, FIG11 shows a schematic block diagram of the structure of the tennis robot in this embodiment. The tennis robot in this embodiment includes a tennis robot body 110, a moving device (i.e., drive wheels 120), a camera assembly (i.e., a vision recognition module 130), a second sensing assembly 321, and a controller 340.

[0172] A mobile device (i.e., drive wheel 120) is located at the bottom of the tennis robot body 110; a camera assembly is fixed to the tennis robot body 110, and the camera assembly includes two visible light cameras (131 and 132); a second sensing assembly 321 is used to acquire the motion information of the tennis robot; a controller 340 is connected to the mobile device (i.e. drive wheel 120), the camera assembly, and the second sensing assembly 321, and is used to control the mobile device (i.e. drive wheel 120) to move the tennis robot to the receiving position based on the motion information and the image containing the tennis ball to be received acquired by the two visible light cameras (131 and 132).

[0173] Visible light cameras can also be understood as monochrome cameras, R (Red) G (Green) B (Blue) cameras, and are not limited to these.

[0174] The receiving position refers to the location on the court where the tennis robot's receiving device 200 can receive the tennis ball to be received.

[0175] In this embodiment, two visible light cameras (131 and 132) are installed on the tennis robot. Driven by the mobile device (i.e., drive wheel 120), these cameras can acquire images of the tennis ball observed at various locations on the court. Based on the images acquired by the two visible light cameras, the real-time position of the tennis ball on the court can be estimated. The second sensing component 321 acquires the tennis robot's motion information, allowing it to obtain its position information on the court. Therefore, the controller 340 can precisely control the mobile device (i.e., drive wheel 120) to move to the receiving position based on the tennis ball's image and motion information. This enables the tennis robot to accurately receive the ball, achieving recycling of the tennis ball during the match and improving the playing experience.

[0176] In one embodiment, referring further to FIG11, the two visible light cameras (131 and 132) are spaced apart by a distance d greater than or equal to 12cm in the width direction Y of the tennis robot body 110, where the width direction Y is the dimensional direction of the tennis robot body 110 in the direction parallel to the ground.

[0177] Preferably, the distance d between the two visible light cameras (131 and 132) in the width direction Y of the tennis robot can be greater than or equal to 20cm, so as to make a more accurate depth estimate of the tennis ball to be hit based on the images acquired by the two visible light cameras (131 and 132).

[0178] In this embodiment, the distance d between the two visible light cameras (131 and 132) in the width direction Y of the tennis robot is greater than or equal to 12cm, which can ensure the field of view of the two visible light cameras and ensure that the images obtained by the two visible light cameras (131 and 132) can accurately estimate the depth of the tennis ball's real-time position on the court.

[0179] In one embodiment, referring to FIG12(a), FIG12(a) shows a schematic diagram of the longitudinal angle between the optical axes of two visible light cameras (131 and 132) and the angle between the optical axes and the ground; the angle between the optical axes of the two visible light cameras (131 and 132) and the ground is less than or equal to 30°.

[0180] For example, the angle between the optical axes of the two visible light cameras (131 and 132) and the ground can be 30°, 20°, 10°, 5°, etc., and is not limited thereto.

[0181] In this embodiment, the angle between the optical axes of the two visible light cameras (131 and 132) and the ground is less than or equal to 30°, which ensures that the two visible light cameras (131 and 132) can capture the tennis ball to be received when the tennis robot is located in most parts of the court.

[0182] In one embodiment, the optical axis angle between the two visible light cameras in space is less than or equal to 30°.

[0183] Referring to Figures 13 and 14, Figure 13 shows a schematic diagram of the lateral viewing angle range of the two visible light cameras (131 and 132) in space in this embodiment; Figure 14 shows a schematic diagram of the angle between the optical axes of the two visible light cameras (131 and 132) in this embodiment. The lateral viewing angle range refers to the viewing angle range of the two visible light cameras (131 and 132) in the direction parallel to the ground.

[0184] For example, the included angle between the axes of the two visible light cameras (131 and 132) in space can be 30°, 29°, 28°, 27°, 26°, 25°, 24°, 23°, 22°, 21°, 20°, 19°, 18°, 17°, 16°, 15°, 14°, 13°, 12°, 11°, 10°, 9°, 8°, 7°, 6°, 5°, 4°, 3°, 2°, 1°, etc., and is not limited thereto.

[0185] In this embodiment, the included angle between the axes of the two visible light cameras (131 and 132) in space is less than or equal to 30°, which ensures that the two visible light cameras can simultaneously capture images of the tennis ball in the horizontal direction, thereby improving the accuracy of the tennis robot in catching the ball.

[0186] In one embodiment, the longitudinal angle between the optical axes of the two visible light cameras in space is less than or equal to 15°.

[0187] Referring to Figures 12(a) and 12(b), Figure 12(b) shows a schematic diagram of the longitudinal viewing angle range of the two visible light cameras (131 and 132) in space in this embodiment. The longitudinal angle between the optical axes of the two visible light cameras in space can be understood as the longitudinal viewing angle range of the two visible light cameras (131 and 132) in space. The longitudinal viewing angle range refers to the viewing angle range of the two visible light cameras in the direction perpendicular to the ground.

[0188] For example, the longitudinal angle between the two visible light cameras (131 and 132) in space can be 15°, 14°, 13°, 12°, 11°, 10°, 9°, 8°, 7°, 6°, 5°, 4°, 3°, 2°, 1°, etc., and is not limited thereto.

[0189] In this embodiment, the longitudinal angle between the two visible light cameras (131 and 132) in space is less than or equal to 15°, which ensures that the two visible light cameras can simultaneously capture images of the tennis ball in the longitudinal direction, thereby improving the accuracy of the tennis robot in catching the ball.

[0190] In one embodiment, the field of view of both visible light cameras ranges from 20° to 100°.

[0191] For example, the field of view of the two visible light cameras are 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, 100°, etc., and are not limited thereto.

[0192] When the field of view is too large, it can cause image distortion, leading to inaccurate estimation of the tennis ball's depth, and situations where distant tennis balls are too small to be recognized. When the field of view is too small, it can result in the tennis ball not being captured in some areas. In this embodiment, the field of view range of both visible light cameras is 20° to 100°, ensuring that the blind spots of the two visible light cameras are less than or equal to 500mm. This ensures that the two visible light cameras can acquire images of the tennis ball from more locations, enabling more accurate prediction of the tennis ball's position and improving the accuracy of receiving the ball.

[0193] In one embodiment, the field of view of both visible light cameras is 35° to 60°.

[0194] For example, the field of view of the two visible light cameras can both be 35°, 36°, 37°, 38°, 39°, 40°, 45°, 50°, 55°, 60°, etc., and are not limited thereto.

[0195] In this embodiment, the field of view of both visible light cameras is 35° to 60°, which ensures that the two visible light cameras can acquire tennis ball images from more positions, enabling more accurate prediction of the tennis ball's position and improving the accuracy of receiving the ball.

[0196] In one embodiment, referring to Figure 11, at least one visible light camera (131 or 132) is at a preset height h above the ground; the preset height h is greater than or equal to 20 cm.

[0197] For example, the preset height h can be 20cm, 25cm, 30cm, 35cm, 40cm, 45cm, 50cm, etc., and can be flexibly set according to actual needs, and is not limited to this.

[0198] In this embodiment, at least one visible light camera (131 or 132) is positioned at a preset height of 20cm or more above the ground to prevent the visible light camera from being too low above the ground and capturing objects unrelated to the tennis ball's trajectory, thus affecting the efficiency and accuracy of tennis ball recognition.

[0199] In one embodiment, referring further to FIG11, the camera assembly in this embodiment also includes image stabilization firmware 350, the hardness of which is greater than that of the tennis robot body 110, so as to fix the camera assembly at a preset position on the tennis robot body 110.

[0200] In this embodiment, two visible light cameras (131 and 132) are fixed to the tennis robot body 110 using an image stabilization firmware 350, ensuring that the relative angle between the two visible light cameras (131 and 132) remains constant. Simultaneously, the image stabilization firmware 350 also ensures that the relative positions of the two visible light cameras (131 and 132), the moving device (i.e., the drive wheel 120), and the tennis robot body 110 remain as constant as possible, improving the accuracy of predicting the receiving position of the tennis ball based on the images acquired by the two visible light cameras (131 and 132), thereby improving the accuracy of the tennis robot's ball-catching. This avoids changes in the relative angle of the cameras due to impacts, vibrations, or other factors, which could lead to larger errors in estimating the position of the tennis ball.

[0201] In one embodiment, the motion information includes acceleration information and angular velocity information; the second sensing component 321 includes an accelerometer and a gyroscope, both of which are electrically connected to the controller 340; the accelerometer is used to acquire acceleration information; and the gyroscope is used to acquire angular velocity information.

[0202] In this embodiment, the rotation angle of the first coordinate system relative to the second coordinate system can be obtained based on angular velocity information. The first coordinate system is a three-dimensional coordinate system with the tennis robot as its origin, and the second coordinate system is a three-dimensional coordinate system with any fixed point on the court as its origin. Based on acceleration information, the position of the tennis robot in the coordinate system established with any fixed point on the court as its origin can be obtained. Combining the image, the angle information of the tennis robot relative to the court's reference origin, and the position of the tennis robot relative to the court's reference origin, the position of the tennis ball on the court can be accurately obtained, improving the tennis robot's accuracy in receiving the ball.

[0203] In one embodiment, referring to FIG15, FIG15 shows a schematic flowchart of the control method in this embodiment. The control method in this embodiment can be executed by the controller 340 in any of the above embodiments, or by other terminals or processors capable of communicating and interacting with the controller 340 in any of the above embodiments, and is not limited thereto. In this embodiment, the control method is executable by the controller 340 in any of the above embodiments.

[0204] The control method includes the following steps S501 to S503.

[0205] Step S501: Receive motion information acquired by the second sensing component in the tennis robot at multiple moments and a set of tennis ball images of the tennis ball to be received captured by the two visible light cameras at multiple moments.

[0206] The tennis image set includes multiple sets of tennis images corresponding to different moments, with each set consisting of tennis images captured by two visible light cameras.

[0207] The moment when the second sensing component 321 acquires motion information corresponds to the moment when the two visible light cameras acquire the tennis ball image set. For example, if the two visible light cameras acquire the tennis ball image at the first moment, then the second sensing component 321 also acquires motion information at the first moment.

[0208] Step S502: Obtain the target predicted motion trajectory of the tennis ball to be received based on the tennis ball image set and motion information.

[0209] By combining the tennis image set corresponding to a specific moment in the tennis image dataset with the motion information of the tennis robot at the same moment, the position of the tennis ball to be caught on the court at that moment can be determined. Based on the positions of the tennis balls to be caught on the court determined at multiple moments, the accurate target trajectory of the tennis ball to be caught can be predicted.

[0210] The court is where the tennis robots play tennis.

[0211] Step S503: Control the moving device to the receiving position according to the target predicted motion trajectory.

[0212] In this embodiment, the tennis robot receives tennis images from two visible light cameras at multiple times, capturing the tennis ball to be caught. Based on the tennis image set and the tennis robot's motion information, the trajectory of the tennis ball to be caught can be predicted. That is, the tennis robot's position on the court is taken into account through the tennis robot's motion information, thus obtaining an accurate target predicted trajectory of the tennis ball to be caught. The endpoint of the tennis ball to be caught in the target predicted trajectory is used as the catching position, which can improve the catching accuracy of the tennis robot.

[0213] In one embodiment, referring to Figure 16, Figure 16 illustrates a flowchart of obtaining the target predicted trajectory of the tennis ball to be caught based on a tennis ball image set and motion information in this embodiment. In this embodiment, the tennis ball image set includes a first tennis ball image set and a second tennis ball image set. Obtaining the target predicted trajectory of the tennis ball to be caught based on the tennis ball image set and motion information includes the following steps S601 to S603.

[0214] Step S601: Receive a first tennis ball image set containing the tennis ball to be received, collected by two visible light cameras at multiple times, and motion information acquired by the second sensing component at corresponding multiple times.

[0215] The first tennis image set includes tennis image groups corresponding to multiple moments, and each tennis image group includes tennis images acquired by two visible light cameras at the same moment.

[0216] The first set of tennis images can be captured by two visible light cameras at the same location on the court at multiple times, or by cameras at different locations on the court at multiple times.

[0217] For example, the tennis robot also includes a serving assembly 330, and a controller 340 is connected to the serving assembly 330. When the serving assembly 330 launches a tennis ball, the mobile device (i.e., the drive wheel 120) does not move, and the first tennis ball image set is acquired at the serving position.

[0218] In another exemplary embodiment, the tennis robot also includes a serving assembly 330, and a controller 340 is connected to the serving assembly 330. When the serving assembly 330 launches a tennis ball, the controller 340 controls two visible light cameras to acquire images of the launched target tennis ball and controls the moving device (i.e., the drive wheel 120) to move to a preset origin position. During the movement, steps S601 to S603 are executed to acquire a first set of tennis ball images and predict the trajectory of the tennis ball. If the predicted trajectory indicates that the receiving position of the tennis ball does not match the preset origin position, the moving device (i.e., the drive wheel 120) is controlled to move towards the predicted position of the tennis ball.

[0219] In practical use, the timing of acquiring the first tennis ball image set can be flexibly set according to actual needs, and is not limited to the example above.

[0220] To ensure that the acquired image set (including the first tennis ball image set and the second tennis ball image set) can accurately represent the position of the tennis ball at the corresponding moment, the two visible light cameras can be configured so that the time interval between the controller 340 receiving the images acquired by the two visible light cameras at the same moment is as small as possible, for example, 1 ms, but not limited thereto.

[0221] Step S602: Based on the first tennis ball image set and the corresponding motion information, control the movement of the tennis robot's mobile device to acquire motion information and the second tennis ball image set during the movement of the mobile device.

[0222] Similar to the first tennis image set, the second tennis image set also includes tennis image groups corresponding to multiple moments. Each tennis image group includes tennis images acquired by two visible light cameras at the same moment.

[0223] It is understood that the tennis robot includes a mobile device (i.e., drive wheel 120), which operates under the drive of the mobile device (i.e., drive wheel 120). The motion information of the mobile device (i.e., drive wheel 120) is also the motion information of the tennis robot. Based on the motion information of the tennis robot, the position of the tennis robot on the court can be obtained. Two visible light cameras are installed on the tennis robot, so the positions of the two visible light cameras on the court can also be obtained. Combining this with the position of the tennis ball to be caught relative to the two visible light cameras, represented by the first tennis ball image set, the position of the tennis ball to be caught on the court can be obtained.

[0224] Therefore, based on the first tennis ball image set and the motion information of the tennis robot, the motion trajectory of the tennis ball to be caught can be initially predicted. Based on the initially predicted motion trajectory, the moving device (i.e., the drive wheel 120) is controlled to move. During the movement, the second tennis ball image set, which is continuously acquired, can also be used. The second tennis ball image set includes more effective position information of the tennis ball to be caught. Therefore, the target predicted motion trajectory of the tennis ball to be caught based on the second tennis ball image set is more accurate.

[0225] Step S603: Obtain the target predicted trajectory of the tennis ball to be caught based on the first tennis ball image set, the second tennis ball image set, and motion information.

[0226] For example, the initial trajectory predicted based on the first tennis image set can be calibrated based on the second tennis image set to obtain a more accurate target predicted trajectory.

[0227] The motion information in step S603 includes motion information corresponding to the first tennis ball image set and motion information during the movement of the tennis robot.

[0228] In this embodiment, a first set of tennis ball images is collected by two visible light cameras of the tennis robot at multiple times. Based on the first set of tennis ball images and the corresponding motion information, the motion trajectory of the tennis ball to be caught can be initially predicted. The tennis robot is controlled to move towards the receiving position of the initially predicted motion trajectory. During the movement, a second set of tennis ball images and motion information are acquired. The motion trajectory initially predicted based on the first set of tennis ball images is calibrated according to the second set of tennis ball images and the motion information during the movement to obtain the target predicted motion trajectory of the tennis ball to be caught, thereby improving the catching accuracy of the tennis robot.

[0229] In one embodiment, referring to FIG17, FIG17 shows a schematic diagram of the process of controlling the movement of the mobile device (i.e., drive wheel 120) of the tennis robot based on the first tennis image set and the corresponding motion information to obtain the motion information and the second tennis image set during the movement of the mobile device (i.e. drive wheel 120).

[0230] In this embodiment, the movement of the tennis robot's mobile device (i.e., drive wheel 120) is controlled based on the first tennis image set and the corresponding motion information to obtain the motion information and the second tennis image set during the movement of the mobile device (i.e., drive wheel 120). This includes the following steps S701 to S703.

[0231] Step S701: Obtain the first coordinates of the tennis ball to be received at multiple moments in the first coordinate system based on the first tennis ball image set.

[0232] The first coordinate system is a three-dimensional coordinate system with the tennis robot as the origin.

[0233] During the movement of the mobile device (i.e., drive wheel 120), the two visible light cameras are always facing the tennis ball to be caught, so as to ensure that the two visible light cameras can acquire images of the tennis ball during the movement.

[0234] For example, the pixel coordinates of the tennis ball to be received in the tennis ball images captured by the two visible light cameras at time i are identified respectively, and the corresponding first coordinates (xci, yci, zci) are obtained by using triangulation, where i is a positive number and the y-axis represents the height of the observation point from the ground.

[0235] Step S702: Obtain the second coordinates of the tennis ball to be received in the second coordinate system at multiple times based on the first coordinates at multiple times and the corresponding motion information.

[0236] The second coordinate system is a three-dimensional coordinate system with any fixed point in the court as the origin.

[0237] The "court" refers to the playing area where tennis robots play tennis.

[0238] For example, the motion information includes the angular velocity and acceleration of the tennis robot. Integrating the angular velocity yields the orientation angle θi of the tennis robot relative to the origin of the second coordinate system at time i. The acceleration provides the coordinates (xri, yri, zri) of the tennis robot relative to the origin of the second coordinate system at time i. The second coordinates (xgi, ygi, zgi) are obtained from the first coordinates, (xri, yri, zri), and the orientation angle θi. Since the tennis robot always moves on the same horizontal plane, i.e., the ground, there is no need to rotate the y-axis. The formulas can be expressed as: xgi = xci × cos(θi) - zci × sin(θi) + xri; ygi = yci; zgi = xci × sin(θi) + zci × cos(θi) + zri.

[0239] Step S703: Control the movement of the mobile device according to the second coordinates corresponding to the tennis ball to be caught at multiple times, so as to obtain the motion information of the mobile device during the movement process and the second tennis ball image set collected by the two visible light cameras.

[0240] In this embodiment, the initial predicted trajectory of the tennis ball to be received can be obtained based on the second coordinates corresponding to multiple times. The moving device (i.e., the drive wheel 120) is controlled to move towards the end point of the initial predicted trajectory. During the movement, motion information and a second tennis ball image set are also acquired at different times, thereby obtaining a more accurate position of the tennis ball to be received on the court during the movement.

[0241] In one embodiment, the second tennis ball image set includes images captured by two visible light cameras at multiple moments during the movement of the mobile device (i.e., drive wheel 120).

[0242] Referring to Figure 18, Figure 18 illustrates a flowchart of the process for obtaining the target predicted trajectory of the tennis ball to be caught based on the first tennis ball image set, the second tennis ball image set, and motion information in this embodiment. In this embodiment, obtaining the target predicted trajectory of the tennis ball to be caught based on the first tennis ball image set, the second tennis ball image set, and motion information includes the following steps S801 to S803.

[0243] Step S801: Obtain the first predicted motion trajectory based on multiple second coordinates corresponding to the first tennis image set.

[0244] In other words, it can be understood that the tennis images in the first tennis image set are the earliest images acquired by the two visible light cameras, and their accuracy in representing the position of the tennis ball to be caught on the court is the lowest. However, based on the first tennis image set and motion information, the approximate direction of motion of the tennis ball to be caught can be determined, providing a reference for the tennis robot to further calibrate the position of the tennis ball to be caught.

[0245] Step S802: Based on the images acquired by the two visible light cameras at the initial moment and the motion information at the initial moment, calibrate the first predicted motion trajectory to obtain the second predicted motion trajectory corresponding to the initial moment.

[0246] The initial moment is the earliest moment among multiple moments in the movement of the moving device (i.e., the drive wheel 120).

[0247] Compared to the position of the tennis ball on the court represented by the first predicted trajectory, the tennis robot has moved, resulting in a better observation position for the ball. Therefore, the image acquired after the movement can more accurately predict the next moment's position of the tennis ball. This tennis ball image is from the second set of tennis ball images, and its position is more accurate than the position predicted by the first predicted trajectory at the same moment. Therefore, calibrating the initial predicted trajectory based on this position allows for a more accurate prediction of the receiving position of the tennis ball.

[0248] For example, referring to Figure 19, which illustrates a tennis robot's movement, assume time 1 precedes time 2. The predicted trajectory of the tennis ball to be received, acquired by the robot at time 1, includes the predicted receiving point. However, the predicted receiving point at time 1 may be inaccurate because the image of the tennis ball was acquired earlier. Compared to time 1, the tennis robot has moved and acquired more images containing information about the tennis ball's position. Therefore, the predicted receiving point at time 2 will be more accurate. Thus, by calibrating the initial predicted trajectory based on the images acquired by the two visible light cameras at the initial time, a more accurate prediction of the receiving position of the tennis ball can be made.

[0249] Step S803: Based on the images acquired by the two visible light cameras at other times and the motion information at other times, the predicted motion trajectory corresponding to the previous moment is successively calibrated to obtain the target predicted motion trajectory corresponding to the last moment.

[0250] The remaining moments are the moments other than the initial moment and the last moment among the multiple moments in the movement of the mobile device (i.e., the drive wheel 120); the last moment is the last moment among the multiple moments in the movement of the mobile device (i.e., the drive wheel 120).

[0251] For example, during the movement of the tennis ball, two visible light cameras acquire images containing the tennis ball to be received at a first moment to a fifth moment. The initial moment is the first moment. Based on the images acquired by the two visible light cameras and the motion information acquired by the second sensing component 321 at the first moment, a first predicted motion trajectory is calibrated to obtain a second predicted motion trajectory. The remaining moments include the second, third, and fourth moments. Based on the images acquired at the second moment and the motion information acquired at the second moment, the second predicted motion trajectory corresponding to the first moment is calibrated to obtain a third predicted motion trajectory; based on the images acquired at the third moment and the motion information acquired at the third moment, the third predicted motion trajectory corresponding to the second moment is calibrated to obtain a fourth predicted motion trajectory; based on the images acquired at the fourth moment and the motion information acquired at the fourth moment, the fourth predicted motion trajectory corresponding to the third moment is calibrated to obtain a fifth predicted motion trajectory. The final moment is the fifth moment. Based on the images acquired at the fifth moment and the motion information acquired at the fifth moment, the fifth predicted motion trajectory corresponding to the fourth moment is calibrated to obtain the target predicted motion trajectory.

[0252] During the movement of the mobile device (i.e., the drive wheel 120), the predicted running trajectory obtained at the previous moment is calibrated based on the tennis ball image and motion information corresponding to each next moment. This ensures that the target predicted running trajectory corresponding to the tennis ball image obtained at the last moment is the most accurate, thereby improving the tennis robot's ball-catching accuracy.

[0253] In one embodiment, both visible light cameras in the tennis robot are configured with master-slave mode or hard-triggered mode, such that the time interval between the controller 340 in the tennis robot receiving the images output by the two visible light cameras is less than or equal to 1ms.

[0254] In this embodiment, the two visible light cameras are configured with a master-slave mode or a hard-triggered mode so that the time interval between the controller 340 receiving the images acquired by the two visible light cameras is less than or equal to 1ms, which can ensure the accuracy of depth estimation of the position of the tennis ball to be hit based on the images acquired by the two visible light cameras.

[0255] In one embodiment, the tennis robot includes a serving component 330, which is connected to a controller 340. The controller 340 can be configured to: calculate and send a serving command to the serving component 330 at a preset time before reaching the receiving position based on the angular velocity and acceleration information acquired in real time by the second sensing component 321. This avoids the time difference between initiating the serving command and the serving component 330 officially sending the ball, which would prevent the second tennis ball from being launched in time when the first tennis ball cannot be received. This ensures that receiving and serving occur almost simultaneously, improving the user experience of the tennis robot.

[0256] In one embodiment, the tennis robot includes a serving component 330, which is connected to a controller 340. The controller 340 can also control the serving speed and angle of the serving component 330 based on the angular velocity and acceleration information collected in real time by the second sensing component 321, as well as control the orientation of the tennis robot towards the tennis opponent, so as to accurately launch the second tennis ball to the position of the opponent on the court.

[0257] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0258] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0259] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples, without contradiction.

[0260] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A ball-receiving device, characterized in that, The ball-receiving device includes: A base having a first surface, and a receiving groove being recessed on the first surface; At least three telescopic members, all of which are circumferentially spaced around the base, with one end or side of each telescopic member connected to the base, and the other end of each telescopic member configured to retractably protrude from the first surface; and A blocking member, configured to be unfoldable and foldable, is connected between each of the telescopic members and the base and serves to enclose a ball-receiving space having a ball-entry port for a tennis ball to enter; the blocking member is used to block a tennis ball entering the ball-receiving space; the ball-receiving space communicates with the receiving groove so that the tennis ball falls into the receiving groove after being blocked.

2. The ball-receiving device according to claim 1, characterized in that, When all the telescopic members are in the extended state, all the telescopic members and the base enclose the ball receiving space; the blocking member unfolds under the action of the telescopic members, the blocking member covers the outside of the ball receiving space, and the ball receiving opening is formed between any two adjacent telescopic members in the ball receiving space. When all the telescopic components are in the shortened state, the shielding component folds under the action of the telescopic components and is at least partially housed in the receiving groove.

3. The ball-receiving device according to claim 1, characterized in that, It also includes a buffer element, which is fitted within the ball receiving space and is configured to be deployable and foldable between each of the telescopic elements and the base; When all the telescopic components are in the extended state, the buffer component unfolds under the action of the telescopic components and is positioned towards the ball inlet; when all the telescopic components are in the shortened state, the buffer component folds and is stored in the receiving groove under the action of the telescopic components.

4. The ball-receiving device according to claim 1, characterized in that, Each of the aforementioned telescopic components includes at least two telescopic sections, and the telescopic sections are sequentially slidably connected to each other.

5. The ball-receiving device according to claim 1, characterized in that, The base also includes a mounting hole for inserting the telescopic member, the mounting hole extending at a predetermined angle A from one end near the bottom to the other end away from the bottom outwards from the base.

6. The ball-receiving device according to claim 5, characterized in that, The preset angle A satisfies the condition: 0°≤A≤45°.

7. The ball-receiving device according to claim 5, characterized in that, The base also includes a base body and a plurality of first connectors. The base body includes the first surface and the receiving groove. Each of the first connectors is arranged on the base body at circumferential intervals around the base, and each of the first connectors is provided with the mounting hole.

8. The ball-receiving device according to claim 7, characterized in that, Each of the first connectors includes a main body and a connecting portion, the connecting portion protruding from the outside of the main body and connected to the base; the main body has a recessed mounting hole.

9. The ball-receiving device according to claim 1, characterized in that, It also includes several first fixing members and first mating members, each of the first fixing members being provided in a one-to-one correspondence with each of the telescopic members and being fitted to the end of the telescopic member away from the base; the first mating member is fitted to the shielding member and is connected to the first fixing member.

10. The ball-receiving device according to claim 9, characterized in that, It also includes a second fixing member and a second mating member, the second fixing member being mated to the base, the second mating member being mated to the shielding member, and the second fixing member being connected to the shielding member.

11. The ball-receiving device according to claim 1, characterized in that, The top of the receiving slot has an inlet for the tennis ball to fall into; the top of the base is provided with a guide part, which is located at the inlet and extends from bottom to top away from the center of the inlet to guide the tennis ball from the receiving space into the receiving slot.

12. The ball-receiving device according to claim 11, characterized in that, The number of guides is two or more, and each guide is arranged at intervals along the outer periphery of the drop inlet.

13. The ball-receiving device according to claim 11, characterized in that, The base includes at least three sidewalls connected in sequence, and the drop-in opening formed by each sidewall is a polygonal opening. The guide portion is connected to the top edge of the sidewall, and the gap formed between adjacent guide portions is above the connection point of two adjacent sidewalls.

14. The ball-receiving device according to claim 11, characterized in that, The guide portion gradually decreases in size from bottom to top along the circumferential direction of the drop inlet.

15. The ball-receiving device according to claim 11, characterized in that, The base includes a first sidewall, and the ball inlet is located above the first sidewall; the base also includes other sidewalls, which are connected to the first sidewall to form the receiving groove, and the guide portion is located on the other sidewalls.

16. The ball-receiving device according to claim 11, characterized in that, The guide section and the base are integrally bent and formed.

17. The ball-receiving device according to any one of claims 1 to 16, characterized in that, The telescopic component includes a first telescopic component and a second telescopic component, and the ball inlet is formed between the first telescopic component and the second telescopic component. The ball-receiving device further includes an elastic connector, and at least one of the first telescopic member and the second telescopic member is connected to the shielding member through the elastic connector.

18. The ball-receiving device according to claim 17, characterized in that, The elastic connector includes a first elastic connector connected to the first telescopic member. The number of the first elastic connectors is two or more. The shielding member has a first connecting edge. Each of the first elastic connectors is connected to the first connecting edge and is arranged at intervals along the first connecting edge. And / or the elastic connector includes a second elastic connector connected to the second telescopic member, the number of the second elastic connectors being two or more, the shielding member having a second connecting edge, and each of the second elastic connectors being connected to the second connecting edge and arranged at intervals along the second connecting edge.

19. The ball-receiving device according to claim 17, characterized in that, The telescopic component further includes a third telescopic component and a fourth telescopic component. The upper end of the third telescopic component is connected to the shielding component, and the lower end of the third telescopic component is mounted on the base. The upper end of the fourth telescopic component is connected to the shielding component, and the lower end of the fourth telescopic component is mounted on the base. The first telescopic component, the second telescopic component, the third telescopic component, and the fourth telescopic component are arranged sequentially at intervals along the circumference of the base.

20. The ball-receiving device according to claim 17, characterized in that, The ball-receiving device further includes a connecting ring connected to the shielding member, and the elastic connecting member is connected to the shielding member through the connecting ring.

21. The ball-receiving device according to claim 17, characterized in that, The elastic connector is an elastic pull rope.

22. The ball-receiving device according to claim 17, characterized in that, The shielding component is an elastic mesh or elastic fabric.

23. The ball-receiving device according to claim 17, characterized in that, The lower end of the shield is connected to the inner wall of the receiving groove.

24. A tennis robot, characterized in that, Includes a ball-dropping assembly, a ball-serving assembly, and a ball-receiving device as described in any one of claims 1 to 23; The ball lowering assembly includes a ball lowering cylinder and a ball rotating module; the ball rotating module has multiple ball positions; The ball-dropping assembly is used in conjunction with the ball-receiving device, which receives the tennis ball and transfers it to the ball-dropping tube, allowing the tennis ball served by the serving assembly to be retrieved by the ball-receiving device. Simultaneously, the retrieved tennis ball can fall onto multiple ball positions for re-serving by the serving assembly; and / or, the ball-receiving device receives the first tennis ball served by the user, and simultaneously, the tennis robot needs to launch a second tennis ball upon receiving the first tennis ball.

25. The tennis robot according to claim 24, characterized in that, The tennis robot further includes a first sensing component and a controller. The first sensing component is used to output a first detection signal to the controller when a tennis ball is detected at a target ball position. The target ball position is one of a plurality of ball positions. The bottom of the lower ball tube is provided with a tennis ball through hole, and the ball rotating module is embedded in the lower ball tube; The controller is electrically connected to the first sensing component and the ball-spinning module respectively, and is used to control the ball-spinning module to drop the tennis ball on the target ball position through the tennis ball through hole to the serving component when the first detection signal is received. The serving component is used to launch the falling tennis ball when a tennis ball is falling through the tennis ball through hole.

26. The tennis robot according to claim 25, characterized in that, When the tennis robot moves to the target position, the controller receives a corresponding electrical signal. At this time, the first gating circuit configured in the controller selects the connection between the first driving circuit and the first sensing component under the action of the corresponding electrical signal. The first driving circuit sends a first driving electrical signal to the first sensing component through the first gating circuit to drive the first sensing component to start working and realize the detection of the target ball position.

27. The tennis robot according to claim 26, characterized in that, Upon receiving the first detection signal, the second gating circuit built into the controller selects the connection between the second drive circuit and the ball-spinning module under the action of the first detection signal. The second drive circuit sends a second drive signal to the ball-spinning module through the second gating circuit to drive the ball-spinning module to start working and control the ball-spinning module to drop the tennis ball on the target ball position through the tennis ball hole to the serving assembly.

28. The tennis robot according to claim 25, characterized in that, The ball-rotating module includes a ball-rotating motor and a ball-rotating cylinder, and the ball-rotating motor is electrically connected to the ball-rotating cylinder and the controller, respectively. The first sensing component is also configured to output a second detection signal when it detects that there is no tennis ball at the target ball position; The controller is used to drive the ball-rotating motor to control the rotation of the ball-rotating cylinder when the second detection signal is received, until a tennis ball is at the target ball position.

29. The tennis robot according to claim 25, characterized in that, The ball-spinning module includes a ball-spinning cylinder, a ball-blocking plate, and a ball-blocking motor. The ball-spinning cylinder has multiple ball positions. The rotating end of the ball-blocking plate is connected to the ball-blocking motor, and the ball-blocking plate is located between the tennis ball through hole and the serving assembly. The first sensing assembly is located on the side of the ball-blocking plate opposite to the tennis ball through hole. The target ball position includes the ball position corresponding to the position of the ball deflector; The controller is used to drive the ball-blocking motor to rotate the ball-blocking plate around the rotating end when the first detection signal is received, so that the tennis ball on the target ball position falls into the serving assembly through the tennis ball through hole.

30. The tennis robot according to claim 29, characterized in that, The first sensing component is also used to output a second detection signal when there is no tennis ball on the ball position corresponding to the ball-blocking plate position; the ball-spinning module also includes a ball-spinning motor, which is connected to the ball-spinning cylinder and the controller; The controller is used to drive the ball-rotating motor to control the ball-rotating cylinder to rotate when the second detection signal is received, until there is a tennis ball at the ball position corresponding to the position of the ball-blocking plate.

31. The tennis robot according to claim 25, characterized in that, The first sensing component is positioned at any location capable of detecting whether a tennis ball is present in the target ball position.

32. The tennis robot according to claim 25, characterized in that, The first sensing component includes any one of an infrared sensor, a gravity sensor, and an ultrasonic sensor.

33. The tennis robot according to any one of claims 25 to 32, characterized in that, The ball-spinning module also includes a ball-limiting plate, which is located on the side of the lower ball tube opposite to the ball-serving assembly. The position of the ball-limiting plate corresponds to the position of the tennis ball through-hole, and is used to limit the number of tennis balls on the ball position corresponding to the position of the tennis ball through-hole to 1.

34. The tennis robot according to any one of claims 24 to 32, characterized in that, It also includes a buffer structure, which is located on the side of the lower tube opposite to the serving assembly, for cushioning the tennis ball falling into the lower tube.

35. The tennis robot according to any one of claims 24 to 32, characterized in that, The difference between the diameter of the through hole and the diameter of a single tennis ball satisfies a preset condition, so that a single tennis ball can pass through the through hole.

36. The tennis robot according to claim 24, characterized in that, It also includes the tennis robot body, mobile device, camera assembly, second sensor assembly, and controller; The mobile device is located at the bottom of the tennis robot body; The camera assembly is fixed to the tennis robot body, and the camera assembly includes two visible light cameras; The second sensing component is used to acquire the motion information of the tennis robot; The controller is connected to the mobile device, the camera assembly, and the second sensing assembly, and is used to control the mobile device to move the tennis robot to the receiving position based on the motion information and the images containing the tennis ball to be received acquired by the two visible light cameras.

37. The tennis robot according to claim 36, characterized in that, The two visible light cameras are spaced at a distance of 12cm or more in the width direction of the tennis robot body, where the width direction is the dimensional direction of the tennis robot body in the direction parallel to the ground.

38. The tennis robot according to claim 36, characterized in that, The angle between the optical axes of the two visible light cameras and the ground is less than or equal to 30°.

39. The tennis robot according to claim 36, characterized in that, The optical axis angle between the two visible light cameras in space is less than or equal to 30°.

40. The tennis robot according to claim 36, characterized in that, The longitudinal angle between the optical axes of the two visible light cameras in space is less than or equal to 15°.

41. The tennis robot according to claim 36, characterized in that, The field of view of both visible light cameras ranges from 20° to 100°.

42. The tennis robot according to claim 41, characterized in that, Both visible light cameras have a field of view of 35° to 60°.

43. The tennis robot according to claim 36, characterized in that, At least one of the visible light cameras is positioned at a predetermined height above the ground; The preset height is greater than or equal to 20cm.

44. The tennis robot according to claim 36, characterized in that, The camera assembly also includes image stabilization firmware, which has a stiffness greater than that of the tennis robot body, to fix the camera assembly to a preset position on the tennis robot body.

45. The tennis robot according to claim 36, characterized in that, The motion information includes acceleration information and angular velocity information; the second sensing component includes an accelerometer and a gyroscope, both of which are electrically connected to the controller; The accelerometer is used to acquire the acceleration information; The gyroscope is used to acquire the angular velocity information.

Images