Tennis ball automatic classification and recycling device and working method thereof

Abstract

The application discloses a tennis ball automatic classification and recovery device and a working method thereof, and belongs to the field of tennis ball classification and recovery. The device comprises a box body, a continuous ball receiving mechanism, a multi-dimensional detection mechanism, a classification and recovery mechanism and a classification and collection mechanism which are sequentially arranged along a tennis ball classification and recovery path. The multi-dimensional detection mechanism is integrated with a position detection unit, an elasticity detection unit and a visual detection unit, which are respectively used for detecting whether the tennis ball is in position, the elasticity of the tennis ball and the quality of the felt, and automatically classifying according to the detection results. The tennis ball automatic classification and recovery device and the working method thereof have the functions of multi-dimensional detection, continuous automatic processing and precise grading, and realize the rapid classification and recovery of tennis balls.

Description

Technical Field

[0001] This invention relates to the field of tennis ball sorting and recycling technology, and in particular to an automatic tennis ball sorting and recycling device and its working method. Background Technology

[0002] With the continuous increase in the popularity of sports worldwide and the rapid iteration of smart technology, tennis, with its combination of competitiveness, social interaction, and fitness value, has gradually penetrated from professional competitions to areas such as mass leisure and youth training, achieving widespread development globally. Accompanying this is a significant increase in tennis usage—whether it's daily training sessions at professional training bases, member coaching at commercial tennis clubs, or pre-match warm-ups and official matches at major tournaments, the number of tennis balls to be recycled after each activity is showing a significant upward trend. If these tennis balls cannot be collected, sorted, and recycled in a timely manner, it will not only waste sports resources but may also affect the normal conduct of subsequent training or matches due to scattered tennis balls on the court. Therefore, the need for efficient recycling, accurate sorting, and intelligent management of tennis balls is becoming increasingly urgent.

[0003] Traditional tennis ball recycling methods rely heavily on manual sorting, which has three major drawbacks: First, low efficiency – staff must enter the court one by one after training or matches to pick up the balls. Due to limitations in human movement speed and physical strength, one staff member can only process 200-300 tennis balls per hour. If there are more than 500 tennis balls to be recycled, 3-5 people are needed to work together, and the recycling cycle can take 1-2 hours. Second, high labor intensity – staff members need to bend over and walk for long periods of time, and tennis courts are mostly made of hard or plastic materials, which can easily lead to back and leg muscle strain. Third, poor classification accuracy – manual labor can only make a preliminary judgment on the appearance of the tennis balls by visual inspection (such as whether there is obvious damage), and cannot accurately identify key quality indicators such as elasticity loss (such as the difference in rebound height after hitting) and felt wear (such as the area of ​​felt shedding and the ball's bounce). This results in rough classification results, which cannot meet the subsequent graded use requirements of "professional training (high elasticity, low wear), beginner practice (medium elasticity, slight wear), and disposal (no elasticity, severe wear)".

[0004] In recent years, with the deep penetration of technologies such as the Internet of Things, machine vision, and automated control into the sports field, the intelligentization of sports equipment has become an important trend in the global sports industry upgrade. From smart rackets that can collect swing data to smart venues that can automatically adjust lighting, temperature, and humidity, and to intelligent referee systems that can analyze movement trajectories, intelligent technologies are gradually reshaping the operational logic of sports scenarios. Against this backdrop, intelligent tennis ball recovery equipment that can replace manual labor has also gradually entered the industry's field of vision and become a key focus for the upgrading and transformation of professional venues.

[0005] However, current smart tennis ball recycling devices on the market still have significant technical limitations, making it difficult to meet practical application needs: First, the identification dimensions are limited—most devices only use a single type of sensor (such as infrared sensors or pressure sensors) for detection, which can only determine "whether a tennis ball exists" and cannot identify key quality parameters such as elasticity, felt wear, and surface flatness from multiple dimensions. This results in limited classification categories (usually only able to distinguish between "usable" and "unusable"), failing to meet the needs of refined grading. Second, the processing efficiency is low—the sorting mechanism mostly adopts a single-channel mechanical conveyor design, which can only process one tennis ball at a time, with a processing capacity of less than 400 balls per hour. Furthermore, due to unreasonable channel design, ball jamming and leakage are prone to occur, further reducing operational efficiency. Third, the adaptability is poor—existing equipment is mostly designed for standard-sized tennis balls, and the recognition rate drops significantly when tennis balls are slightly deformed or have dust on their surface, and it cannot flexibly adjust the classification standards according to the needs of the venue (such as different clubs having different wear threshold requirements for "usable tennis balls"). These shortcomings make it difficult for existing equipment to meet the actual needs of large venues that require "high intensity (more than 2,000 items per day), multiple batches (3-4 recycling cycles per day), and refined (classification at level 4 or above)," thus failing to truly replace the manual recycling model. Summary of the Invention

[0006] The purpose of this invention is to provide an automatic tennis ball sorting and recycling device and its working method, thereby solving the above-mentioned technical problems.

[0007] To achieve the above objectives, the present invention provides an automatic tennis ball sorting and recycling device, comprising a box and a continuous ball receiving mechanism, a multi-dimensional detection mechanism, a sorting and recycling mechanism, and a sorting and collecting mechanism arranged sequentially along the tennis ball sorting and recycling path. The multi-dimensional detection mechanism integrates a positioning detection unit, an elasticity detection unit, and a vision detection unit, which are used to detect whether the tennis ball is in position, the elasticity of the tennis ball, and the quality of the felt, respectively, and to automatically sort the tennis ball based on the detection results.

[0008] Preferably, the continuous ball receiving mechanism includes a ball receiving box connected to a ball receiving port opened at the top of the box and a double-layer rotary unloading platform aligned with the bottom outlet of the ball receiving box. The double-layer rotary unloading platform includes an upper turntable that is horizontally rotated inside the box via a first drive motor and an upper central shaft, and a lower fixed plate that is fixed inside the box. The upper turntable and the lower fixed plate are arranged coaxially.

[0009] Multiple buffer ports are evenly arranged in a circular array on the upper turntable and at the position of the bottom outlet of the ball receiving box. Multiple feeding ports are evenly arranged in a circular array on the lower fixed plate. The ring formed by the centers of the multiple buffer ports coincides with the ring formed by the multiple feeding ports in the vertical direction, and the number of buffer ports is an integer multiple of the number of feeding ports.

[0010] A first electric baffle is provided on the discharge port. A first through-beam photoelectric sensor and a second through-beam photoelectric sensor are respectively provided at the outlet end of the ball receiving box and the inlet end of the multi-dimensional detection mechanism. Both the first through-beam photoelectric sensor and the second through-beam photoelectric sensor are electrically connected to the input end of the controller. The output end of the controller is electrically connected to the first electric baffle and the first drive motor respectively to achieve continuous ball receiving.

[0011] Preferably, a multi-dimensional detection mechanism is fixed below each discharge port. The multi-dimensional detection mechanism includes an upper ball transport channel fixed at the top and bottom of the lower fixed plate and connected to the discharge port, a detection box connected to the bottom of the upper ball transport channel, and a lower ball transport channel connected to the side wall of the detection box. A detection groove is fixed inside the detection box at the discharge port position corresponding to the upper ball transport channel, and the detection groove is connected to the lower ball transport channel.

[0012] A ball-pushing assembly is provided on one side of the testing box corresponding to the testing slot, and a lower ball-driving channel is provided on the other side of the testing box symmetrical to the ball-pushing assembly, which is used to push the tennis ball temporarily stored on the testing slot to the lower ball-driving channel using the ball-pushing assembly.

[0013] At the end of the upper dribbling channel, there is a photoelectric sensor for detecting whether the tennis ball is in position. An elastic detection component is arranged on the top of the detection box and corresponding to the top of the detection slot. A vision detection component is also arranged on the detection box and diagonally above the detection slot. The photoelectric sensor, elastic detection component and vision detection component are all connected to the controller. The controller is connected to the human-machine interaction system.

[0014] Preferably, the elasticity detection component includes an electric push rod fixed to the top of the detection box and a force sensor disposed at the power output end of the electric push rod, with the force sensor located directly above the detection slot;

[0015] The detection groove is an arc-shaped groove structure adapted to tennis balls.

[0016] Preferably, the sorting and recycling mechanism includes a sorting bin aligned with the outlet of the lower ball conveying channel, and an inclined feeding channel is provided at the top of the sorting bin. The height of the end of the inclined feeding channel near the lower ball conveying channel is higher than the height of the end of the inclined feeding channel away from the lower ball conveying channel.

[0017] Inside the sorting bin, multiple independent bins are arranged sequentially along the direction of the inclined feeding channel. The top of the independent bin furthest from the lower ball conveying channel is provided with a normally open opening, and the top of the remaining independent bins is provided with a second electric baffle. Multiple second electric baffles are connected end to end to form an inclined feeding channel.

[0018] The side of the sorting compartment away from the lower ball-carrying channel is fixedly connected to the lower central shaft. The lower central shaft passes through the center of the sorting tray and is connected to the output end of the second drive motor fixed inside the box. Rollers are provided at the bottom end of the side of the sorting compartment closest to the lower ball-carrying channel.

[0019] The second drive motor and the second electric baffle are both electrically connected to the controller;

[0020] The sorting tray is fixed inside the box, and the sorting tray has sorting openings in the radial direction that correspond one-to-one with multiple independent compartments. The number of independent compartments is no less than the number of grades for tennis balls.

[0021] Preferably, the sorting and collection mechanism includes a flexible tube connected to a sorting port at one end and an independent collection chamber connected to the other end of the flexible tube. The independent collection chamber is fixed to the box body, and a ball retrieval port is provided on the independent collection chamber on one side symmetrical to the flexible tube.

[0022] A method for operating an automatic tennis ball sorting and recycling device includes the following steps:

[0023] S1. A tennis ball is inserted into the receiving port. Under the action of gravity, the tennis ball enters the receiving box and then falls into the buffer port of the upper turntable. During the process of the tennis ball falling from the receiving box, the first photoelectric sensor is blocked and transmits the blocking signal to the controller. The controller turns on the first drive motor and opens the first electric baffle at the discharge port closest to the receiving box. The first drive motor drives the upper central shaft and the upper turntable to rotate synchronously. During the rotation, the tennis ball at the buffer port rolls on the top surface of the lower fixed plate until the center of the buffer port carrying the tennis ball is connected to the center of the discharge port closest to the receiving box. The tennis ball falls into the discharge port and enters the upper ball transport channel of the corresponding multi-dimensional detection mechanism. During the process of the tennis ball entering the upper ball transport channel of the multi-dimensional detection mechanism, the second photoelectric sensor is blocked and transmits the blocking signal to the controller. The controller closes the first electric baffle on the discharge port.

[0024] S2. The tennis ball enters the upper ball transport channel from the feeding port, and then enters the detection tank along the upper ball transport channel. After the photoelectric sensor detects that the tennis ball is in place, it triggers the elasticity detection component and the vision detection component to act simultaneously, respectively detecting the elasticity of the tennis ball and the quality of the felt, and transmitting the detection results back to the controller to generate the tennis ball classification result. The tennis balls that are classified enter the classification and recycling mechanism through the lower ball transport channel.

[0025] S3. Determine the corresponding independent bin based on the tennis ball grading results, and determine whether the tennis ball grade is the last grade. If so, the second electric baffle does not move, and the falling tennis ball rolls through the inclined feeding channel to the independent bin furthest from the lower ball feeding channel. Otherwise, open the second electric baffle corresponding to the independent bin of the corresponding grade, and the falling tennis ball rolls through the inclined feeding channel to the independent bin with the second electric baffle open. The second drive motor drives the sorting bin to rotate on the upper surface of the sorting plate until the independent bin is aligned with the corresponding sorting port. All the tennis balls in this independent bin fall into the sorting collection mechanism through the sorting port. This process is repeated to align each independent bin with the corresponding sorting port and discharge the tennis balls in the corresponding independent bin.

[0026] S4. The falling tennis balls are collected in individual collection chambers through the hoses of the sorting and collection mechanism.

[0027] Preferably, in step S1, when the ball receiving box continuously drops balls to the buffer port, after the controller receives the blocking signal from the first photoelectric sensor, it sequentially opens the second electric baffle at the corresponding discharge port in order of distance from the ball receiving box, and closes the discharge ports that are ordered before the opened discharge ports, and so on, to realize the continuous conveying of tennis balls.

[0028] Preferably, step S2 specifically includes the following steps:

[0029] S21. The tennis ball entering from the feed port slides down the upper ball-carrying channel under the action of gravity. When the tennis ball is completely in the detection slot, the tennis ball blocks the photoelectric sensor at the end of the upper ball-carrying channel. The photoelectric sensor transmits the arrival trigger signal to the controller, and the controller sends the start detection command to the vision detection component and the elastic detection component in sequence.

[0030] S22, The vision detection component is triggered, and the backlight acquires an image of the tennis ball surface;

[0031] S23. The controller controls the electric push rod of the elastic detection component to extend downward at a set speed, bringing the force sensor closer to the tennis ball surface. When the pressure value detected by the force sensor reaches the initial contact threshold... At that time, the force sensor sends a contact signal to the controller, and the controller records the contact time point. The electric actuator continues to extend downwards until the pressure value detected by the force sensor reaches the set maximum pressure. Record this time point. The controller controls the electric push rod to reset;

[0032] S24. The controller calculates the residual elasticity index of the tennis ball based on the data collected by the force sensor. :

[0033] ;

[0034] Simultaneously, the tennis ball surface image is preprocessed, including image binarization, image downsampling compression, sliding window filtering, edge detection, and image enhancement, which are set sequentially to output a mask image. Then, the mask image is input into the pre-trained Stn-Dsc Net model to output the felt quality levels A, B, and C.

[0035] S25, Based on the residual elasticity index value of tennis balls Calculating the overall evaluation index of tennis balls based on the quality level of felt :

[0036] ;

[0037] In the formula, and These represent the weighting coefficients for the elasticity index and the felt index, respectively. express The normalized value; This indicates the quality index value of tennis felt, and ;

[0038] S26. Overall evaluation indicators The tennis grading results are obtained by comparing the results with the preset tennis grading thresholds.

[0039] Therefore, the present invention, employing the above-mentioned automatic tennis ball sorting and recycling device and its working method, has the following beneficial effects:

[0040] 1. High processing efficiency: Through the continuous ball receiving and transfer design of the double-layer rotary feeding platform, multiple tennis balls can enter the testing stage in an orderly manner, breaking through the limitations of single-channel processing and increasing the processing capacity per unit time;

[0041] 2. High classification accuracy: With the help of photoelectric, elasticity and vision multi-unit collaborative detection, it covers key indicators such as tennis ball positioning, elasticity and felt quality, to meet the needs of fine classification.

[0042] 3. High degree of automation: From receiving the ball, detection, grading to collection, no human intervention is required throughout the entire process, reducing high-intensity labor such as bending over to pick up the ball and lowering labor costs;

[0043] 4. High adaptability: By setting the number of independent compartments and linking them with the second electric baffle and drive motor, the classification level can be flexibly adjusted to adapt to the graded use needs of different scenarios.

[0044] 5. Convenient to use: The sorting and collection mechanism uses a flexible tube and an independent collection compartment. The ball retrieval port design makes it easy and quick to retrieve the sorted tennis balls, improving the user experience.

[0045] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the overall structure of an automatic tennis ball sorting and recycling device according to the present invention;

[0047] Figure 2 This is a perspective view of the continuous ball-catching mechanism of an automatic tennis ball sorting and recycling device according to the present invention;

[0048] Figure 3 This is an axial sectional view of the continuous ball-catching mechanism of an automatic tennis ball sorting and recycling device according to the present invention;

[0049] Figure 4 This is a schematic diagram of the upper turntable of the continuous ball receiving mechanism of an automatic tennis ball sorting and recycling device according to the present invention.

[0050] Figure 5 This is a schematic diagram of one perspective of the multi-dimensional detection mechanism of an automatic tennis ball sorting and recycling device according to the present invention.

[0051] Figure 6 This is another perspective schematic diagram of the multi-dimensional detection mechanism of the automatic tennis ball sorting and recycling device of the present invention;

[0052] Figure 7 This is a schematic diagram from one perspective of the sorting and recycling mechanism of an automatic tennis ball sorting and recycling device according to the present invention;

[0053] Figure 8 This is a schematic diagram from another perspective of the sorting and recycling mechanism of an automatic tennis ball sorting and recycling device according to the present invention;

[0054] Figure 9 This is a schematic diagram of the sorting and collection mechanism of an automatic tennis ball sorting and recycling device according to the present invention;

[0055] Figure 10 This is an external view of an automatic tennis ball sorting and recycling device according to the present invention.

[0056] Figure Labels

[0057] 1. Box body; 11. Ball receiving port; 2. Continuous ball receiving mechanism; 21. Ball receiving box; 22. Upper turntable; 23. Lower fixed plate; 24. Upper central shaft; 25. Buffer port; 26. Discharge port; 27. First electric baffle; 28. First through-beam photoelectric sensor; 3. Multi-dimensional detection mechanism; 31. Upper ball transport channel; 32. Ball pushing assembly; 33. Lower ball transport channel; 34. Vision detection assembly; 35. Detection box; 36. Elasticity detection assembly; 37. Detection groove; 38. Second through-beam photoelectric sensor; 4. Sorting and recycling mechanism; 41. Lower central shaft; 42. Sorting bin; 43. Sorting plate; 44. Inclined discharge channel; 45. Independent bin; 46. Sorting port; 47. Second electric baffle; 48. Roller; 5. Sorting and collection mechanism; 51. Hose; 52. Independent collection bin; 53. Ball retrieval port; 6. Tennis ball. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the 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.

[0059] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0060] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0061] like Figures 1-10 As shown, an automatic tennis ball sorting and recycling device includes a box 1 and a continuous ball receiving mechanism 2, a multi-dimensional detection mechanism 3, a sorting and recycling mechanism 4, and a sorting and collection mechanism 5 arranged sequentially along the sorting and recycling path of the tennis balls 6. The multi-dimensional detection mechanism 3 integrates a positioning detection unit, an elasticity detection unit, and a vision detection unit, which are used to detect whether the tennis ball 6 is in position, the elasticity of the tennis ball 6, and the quality of the felt, respectively, and to automatically sort the tennis balls based on the detection results.

[0062] Specifically, the continuous ball receiving mechanism 2 includes a ball receiving box 21 connected to a ball receiving port 11 located at the top of the housing 1, and a double-layer rotary unloading platform aligned with the bottom outlet of the ball receiving box 21. The double-layer rotary unloading platform includes an upper turntable 22 horizontally rotated inside the housing 1 via a first drive motor and an upper central shaft 24, and a lower fixed plate 23 fixed inside the housing 1. The upper turntable 22 and the lower fixed plate 23 are arranged coaxially. The upper turntable 22 receives balls on and corresponding to the ball receiving mechanism. Multiple buffer ports 25 are evenly arranged in a circular array at the bottom outlet of box 21. Multiple discharge ports 26 are evenly arranged in a circular array on the lower fixed plate 23. The annulus formed by the centers of the multiple buffer ports 25 coincides with the annulus formed by the multiple discharge ports 26 in the vertical direction, and the number of buffer ports 25 is an integer multiple of the number of discharge ports 26. In this embodiment, 6 buffer ports 25 are evenly arranged on the upper turntable 22, and 3 discharge ports 26 are evenly arranged on the lower fixed plate 23. A first electric baffle 27 is provided on the discharge port 26. A first through-beam photoelectric sensor 28 and a second through-beam photoelectric sensor 38 are respectively provided at the outlet end of the ball receiving box 21 and the inlet end of the multi-dimensional detection mechanism. The first through-beam photoelectric sensor 28 and the second through-beam photoelectric sensor 38 are both electrically connected to the input end of the controller. The output end of the controller is electrically connected to the first electric baffle 27 and the first drive motor to achieve continuous ball receiving.

[0063] Below each discharge port 26, a multi-dimensional detection mechanism 3 is fixed (i.e., there are three sets of multi-dimensional detection mechanisms 3). The multi-dimensional detection mechanism 3 includes an upper ball-carrying channel 31 fixed at the top and bottom of the lower fixed plate 23 and connected to the discharge port 26, a detection box 35 connected to the bottom of the upper ball-carrying channel 31, and a lower ball-carrying channel 33 connected to the side wall of the detection box 35. Inside the detection box 35, at the position corresponding to the discharge port of the upper ball-carrying channel 31, a detection groove 37 is fixed, and the detection groove 37 is connected to the lower ball-carrying channel 33. A ball-pushing assembly 32 is provided on the detection box 35 on one side corresponding to the detection groove 37, and a ball-pushing assembly 32 is provided. On the other side of the detection box 35, there is a lower ball-driving channel 33, which is used to push the tennis ball 6 temporarily stored on the detection slot 37 to the lower ball-driving channel 33 using the ball-pushing assembly 32 (electric push rod structure); at the end of the upper ball-driving channel 31, there is a photoelectric sensor for detecting whether the tennis ball 6 is in place. An elastic detection assembly 36 is arranged on the detection box 35 and at the top of the detection slot 37. A vision detection assembly 34 is also arranged on the detection box 35 and diagonally above the detection slot 37. The photoelectric sensor, the elastic detection assembly 36 and the vision detection assembly 34 are all connected to the controller, and the controller is connected to the human-machine interaction system.

[0064] The elastic detection component 36 includes an electric push rod fixed to the top of the detection box 35 and a force sensor located at the power output end of the electric push rod. The force sensor is located directly above the detection groove 37. The detection groove 37 is an arc-shaped groove structure adapted to the tennis ball 6.

[0065] It should be noted that the above electronic components are all mature products on the market. This embodiment only requires purchasing them and connecting them according to the instruction manual. No modifications have been made to them. Therefore, their circuit connection structure and principle will not be described in detail here.

[0066] The sorting and recycling mechanism 4 includes a sorting bin 42 aligned with the outlet of the lower ball conveying channel 33. An inclined feeding channel 44 is provided at the top of the sorting bin 42, with the end of the inclined feeding channel 44 closer to the lower ball conveying channel 33 having a higher height than the end further away from the lower ball conveying channel 33. Multiple independent bins 45 are arranged sequentially inside the sorting bin 42 along the direction of the inclined feeding channel 44. The top of the independent bin 45 furthest from the lower ball conveying channel 33 has a normally open top, while the tops of the remaining independent bins 45 are equipped with second electric baffles 47. Multiple second electric baffles 47 are connected end-to-end to form the inclined feeding channel 44. The side of the sorting bin 42 furthest from the lower ball conveying channel 33 is fixedly connected to a lower central shaft 41. After passing through the center of the sorting tray 43, 41 is connected to the output end of the second drive motor fixed inside the box 1; a roller 48 is provided at the bottom end of the sorting compartment 42 near the lower ball channel 33; the second drive motor and the second electric baffle 47 are both electrically connected to the controller; the sorting tray 43 is fixed inside the box 1, and sorting ports 46 corresponding to multiple independent compartments 45 are opened in the radial direction of the sorting tray 43. The number of independent compartments 45 is not less than the number of grades of the tennis ball 6. In this embodiment, the tennis ball 6 is divided into four grades, and four independent compartments 45 (independent compartments 45 have an opening structure at the top and bottom) and four sorting ports 46 are set accordingly. The four sorting ports 46 are asymmetrically arranged on both sides of a certain diameter line of the sorting tray 43.

[0067] The sorting and collection mechanism 5 includes a flexible tube 51 connected to the sorting port 46 at one end and an independent collection chamber 52 connected to the other end of the flexible tube 51. The independent collection chamber 52 is fixed on the box body 1, and a ball retrieval port 53 is provided on the independent collection chamber 52 on one side symmetrical to the flexible tube 51.

[0068] A method for operating an automatic tennis ball sorting and recycling device includes the following steps:

[0069] S1. A tennis ball 6 is inserted into the receiving port 11. Under the action of gravity, the tennis ball 6 enters the receiving box 21 and then falls into the buffer port 25 of the upper turntable 22. During the process of the tennis ball 6 falling from the receiving box 21, the first through-beam photoelectric sensor is blocked and transmits the blocking signal to the controller. The controller turns on the first drive motor and opens the first electric baffle at the discharge port 26 closest to the receiving box 21. The first drive motor drives the upper central shaft 24 and the upper turntable 22 to rotate synchronously. During the rotation, the tennis ball 6 at the buffer port 25 rolls on the top surface of the lower fixed plate 23 until the center of the buffer port 25 carrying the tennis ball 6 is connected to the center of the discharge port 26 closest to the receiving box 21. The tennis ball 6 falls into the discharge port 26 and enters the upper ball transport channel 31 of the corresponding multi-dimensional detection mechanism. During the process of the tennis ball 6 entering the upper ball transport channel 31 of the multi-dimensional detection mechanism, the second through-beam photoelectric sensor is blocked and transmits this blocking signal to the controller. The controller closes the first electric baffle on the discharge port 26.

[0070] In step S1, when the ball receiving box 21 continuously drops balls to the buffer port 25, the controller receives the blocking signal from the first photoelectric sensor and then opens the second electric baffle at the corresponding feed port 26 in order from near to far from the ball receiving box 21, and closes the feed ports that are in order before the opened feed ports. This cycle is repeated to realize the continuous conveying of tennis balls.

[0071] S2. Tennis ball 6 enters the upper ball transport channel 31 through the feeding port 26, and then enters the detection groove 37 along the upper ball transport channel 31. After the photoelectric sensor detects that tennis ball 6 is in place, it triggers the elasticity detection component 36 and the vision detection component 34 to act simultaneously, respectively detecting the elasticity and felt quality of tennis ball 6, and sending the detection results back to the controller to generate the tennis ball 6 grading result. The tennis ball 6 that is classified enters the classification and recycling mechanism 4 through the lower ball transport channel 33.

[0072] Step S2 specifically includes the following steps:

[0073] S21. The tennis ball 6, which enters through the discharge port 26, slides down the upper ball-carrying channel 31 under the action of gravity. When the tennis ball 6 is fully inside the detection groove 37, the tennis ball 6 blocks the photoelectric sensor at the end of the upper ball-carrying channel 31. The photoelectric sensor transmits the arrival trigger signal to the controller, and the controller sends the start detection command to the vision detection component and the elastic detection component in sequence.

[0074] S22, The vision detection component is triggered, and the backlight acquires an image of the tennis ball surface;

[0075] S23. The controller controls the electric push rod of the elastic detection component to extend downward at a set speed, bringing the force sensor closer to the tennis ball surface. When the pressure value detected by the force sensor reaches the initial contact threshold... At that time, the force sensor sends a contact signal to the controller, and the controller records the contact time point. The electric actuator continues to extend downwards until the pressure value detected by the force sensor reaches the set maximum pressure. Record this time point. The controller controls the electric push rod to reset;

[0076] S24. The controller calculates the residual elasticity index of the tennis ball based on the data collected by the force sensor. :

[0077] ;

[0078] Simultaneously, the tennis ball surface image is preprocessed, including image binarization, image downsampling compression, sliding window filtering, edge detection, and image enhancement, outputting a mask image. This mask image is then input into a pre-trained Stn-Dsc Net model to output felt quality levels A, B, and C. In this embodiment, the Stn-Dsc Net model includes an input layer, an STN module (Spatial Transform Network), a DSConv layer (Dynamic Snake Convolution), an SE attention mechanism module, and a classification decision layer. The STN module corrects the input mask image. The DSConv layer adapts to the "long, curved, and multi-branched" structural characteristics of the fibers, avoiding the loss of fiber features by the receptive field of traditional rectangular convolution, and extracts features. The SE attention mechanism module focuses on fiber damage areas, suppresses background noise, and improves the specificity of feature expression.

[0079] S25, Based on the residual elasticity index value of tennis balls Calculating the overall evaluation index of tennis balls based on the quality level of felt :

[0080] ;

[0081] In the formula, and These represent the weighting coefficients for the elasticity index and the felt index, respectively. It should be noted that... This determines whether to focus more on elasticity quality or felt quality in the overall evaluation. Under the premise that, if They believe that flexibility indicators are more important in overall quality evaluation; if It is believed that in the overall quality evaluation, elasticity indicators and felt quality indicators are equally important; if They believe that the felt index is more important in overall quality considerations; express The normalized value; This indicates the quality index value of tennis felt, and ;

[0082] S26. Overall evaluation indicators The tennis grading results are obtained by comparing the results with the preset tennis grading thresholds.

[0083] S3. Based on the grading results of tennis balls 6, determine the corresponding independent bin 45 and whether tennis balls 6 is the last grade. If so, the second electric baffle 47 does not move, and the falling tennis balls 6 roll through the inclined feeding channel 44 to the independent bin 45 furthest from the lower ball passage 33. Otherwise, open the second electric baffle 47 corresponding to the independent bin 45 of the corresponding grade, and the falling tennis balls 6 roll through the inclined feeding channel 44 to the independent bin 45 with the second electric baffle 47 open. The second drive motor drives the sorting bin 42 to rotate on the upper surface of the sorting plate 43 until the independent bin 45 is aligned with the corresponding sorting port 46. All the tennis balls 6 in this independent bin 45 fall into the sorting and collecting mechanism 5 through the sorting port 46. This process is repeated so that each independent bin 45 is aligned with the corresponding sorting port 46, and the tennis balls 6 in the corresponding independent bin 45 are discharged.

[0084] S4. The falling tennis ball 6 enters the independent collection chamber 52 through the hose 51 of the sorting and collection mechanism 5 for collection.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An automatic tennis ball sorting and recycling device, characterized in that: The system includes a box and a continuous ball-catching mechanism, a multi-dimensional detection mechanism, a sorting and recycling mechanism, and a sorting and collection mechanism arranged sequentially along the tennis ball sorting and recycling path. The multi-dimensional detection mechanism integrates a positioning detection unit, an elasticity detection unit, and a vision detection unit, which are used to detect whether the tennis ball is in position, the elasticity of the tennis ball, and the quality of the felt, respectively, and automatically sort the tennis balls based on the detection results. The continuous ball receiving mechanism includes a ball receiving box connected to a ball receiving port opened at the top of the box and a double-layer rotary unloading platform aligned with the bottom outlet of the ball receiving box. The double-layer rotary unloading platform includes an upper turntable that is horizontally rotated inside the box via a first drive motor and an upper central shaft, and a lower fixed plate that is fixed inside the box. The upper turntable and the lower fixed plate are arranged coaxially. Multiple buffer ports are evenly arranged in a circular array on the upper turntable and at the position of the bottom outlet of the ball receiving box. Multiple feeding ports are evenly arranged in a circular array on the lower fixed plate. The ring formed by the centers of the multiple buffer ports coincides with the ring formed by the multiple feeding ports in the vertical direction, and the number of buffer ports is an integer multiple of the number of feeding ports. A first electric baffle is provided on the discharge port. A first through-beam photoelectric sensor and a second through-beam photoelectric sensor are respectively provided at the outlet end of the ball receiving box and the inlet end of the multi-dimensional detection mechanism. Both the first through-beam photoelectric sensor and the second through-beam photoelectric sensor are electrically connected to the input end of the controller. The output end of the controller is electrically connected to the first electric baffle and the first drive motor respectively to achieve continuous ball receiving. Below each discharge port is a multi-dimensional detection mechanism, which includes an upper ball-carrying channel fixed at the bottom of the top and bottom of the lower fixed plate and connected to the discharge port, a detection box connected to the bottom of the upper ball-carrying channel, and a lower ball-carrying channel connected to the side wall of the detection box. Inside the detection box, at the discharge port position corresponding to the upper ball-carrying channel, there is a detection groove, which is connected to the lower ball-carrying channel. A ball-pushing assembly is provided on one side of the testing box corresponding to the testing slot, and a lower ball-driving channel is provided on the other side of the testing box symmetrical to the ball-pushing assembly, which is used to push the tennis ball temporarily stored on the testing slot to the lower ball-driving channel using the ball-pushing assembly. At the end of the upper dribbling channel, there is a photoelectric sensor for detecting whether the tennis ball is in place. An elastic detection component is arranged on the top of the detection box and corresponding to the top of the detection slot. A vision detection component is also arranged on the detection box and diagonally above the detection slot. The photoelectric sensor, elastic detection component and vision detection component are all connected to the controller. The controller is connected to the human-machine interaction system. The sorting and recycling mechanism includes a sorting bin aligned with the outlet of the lower ball conveying channel. An inclined feeding channel is provided at the top of the sorting bin. The height of the end of the inclined feeding channel near the lower ball conveying channel is higher than the height of the end of the inclined feeding channel away from the lower ball conveying channel. Inside the sorting bin, along the direction of the inclined feeding channel, there are multiple independent bins arranged in sequence. The top of the independent bin furthest from the lower ball conveying channel is provided with a normally open opening, and the top of the remaining independent bins is provided with a second electric baffle. Multiple second electric baffles are connected end to end to form an inclined feeding channel. The side of the sorting compartment away from the lower ball-carrying channel is fixedly connected to the lower central shaft. The lower central shaft passes through the center of the sorting tray and is connected to the output end of the second drive motor fixed inside the box. Rollers are provided at the bottom end of the side of the sorting compartment closest to the lower ball-carrying channel. The second drive motor and the second electric baffle are both electrically connected to the controller; The sorting tray is fixed inside the box, and the sorting tray has sorting openings in the radial direction that correspond one-to-one with multiple independent compartments. The number of independent compartments is no less than the number of grades for tennis balls.

2. The automatic tennis ball sorting and recycling device according to claim 1, characterized in that: The elasticity detection assembly includes an electric push rod fixed to the top of the detection box and a force sensor located at the power output end of the electric push rod, with the force sensor positioned directly above the detection slot. The detection groove is an arc-shaped groove structure adapted to tennis balls.

3. The automatic tennis ball sorting and recycling device according to claim 2, characterized in that: The sorting and collection mechanism includes a flexible tube connected to the sorting port at one end and an independent collection chamber connected to the other end of the flexible tube. The independent collection chamber is fixed to the box body, and a ball retrieval port is opened on the independent collection chamber on one side symmetrical to the flexible tube.

4. The working method of the automatic tennis ball sorting and recycling device as described in claim 3, characterized in that: Includes the following steps: S1. A tennis ball is inserted into the receiving port. Under the action of gravity, the tennis ball enters the receiving box and then falls into the buffer port of the upper turntable. During the process of the tennis ball falling from the receiving box, the first photoelectric sensor is blocked and transmits the blocking signal to the controller. The controller turns on the first drive motor and opens the first electric baffle at the discharge port closest to the receiving box. The first drive motor drives the upper central shaft and the upper turntable to rotate synchronously. During the rotation, the tennis ball at the buffer port rolls on the top surface of the lower fixed plate until the center of the buffer port carrying the tennis ball is connected to the center of the discharge port closest to the receiving box. The tennis ball falls into the discharge port and enters the upper ball transport channel of the corresponding multi-dimensional detection mechanism. During the process of the tennis ball entering the upper ball transport channel of the multi-dimensional detection mechanism, the second photoelectric sensor is blocked and transmits the blocking signal to the controller. The controller closes the first electric baffle on the discharge port. S2. The tennis ball enters the upper ball transport channel from the feeding port, and then enters the detection tank along the upper ball transport channel. After the photoelectric sensor detects that the tennis ball is in place, it triggers the elasticity detection component and the vision detection component to act simultaneously, respectively detecting the elasticity of the tennis ball and the quality of the felt, and transmitting the detection results back to the controller to generate the tennis ball classification result. The tennis balls that are classified enter the classification and recycling mechanism through the lower ball transport channel. S3. Determine the corresponding independent bin based on the tennis ball grading results, and determine whether the tennis ball grade is the last grade. If so, the second electric baffle does not move, and the falling tennis ball rolls through the inclined feeding channel to the independent bin furthest from the lower ball feeding channel. Otherwise, open the second electric baffle corresponding to the independent bin of the corresponding grade, and the falling tennis ball rolls through the inclined feeding channel to the independent bin with the second electric baffle open. The second drive motor drives the sorting bin to rotate on the upper surface of the sorting plate until the independent bin is aligned with the corresponding sorting port. All the tennis balls in this independent bin fall into the sorting collection mechanism through the sorting port. This process is repeated to align each independent bin with the corresponding sorting port and discharge the tennis balls in the corresponding independent bin. S4. The falling tennis balls are collected in individual collection chambers through the hoses of the sorting and collection mechanism.

5. The working method of the automatic tennis ball sorting and recycling device according to claim 4, characterized in that: In step S1, when the ball is continuously dropped from the receiving box to the buffer port, the controller receives the blocking signal from the first photoelectric sensor and then opens the second electric baffle at the corresponding discharge port in sequence from near to far from the receiving box, and closes the discharge port before the opened discharge port. This cycle is repeated to achieve continuous conveying of tennis balls.

6. The working method of the automatic tennis ball sorting and recycling device according to claim 5, characterized in that: Step S2 specifically includes the following steps: S21. The tennis ball entering from the feed port slides down the upper ball-carrying channel under the action of gravity. When the tennis ball is completely in the detection slot, the tennis ball blocks the photoelectric sensor at the end of the upper ball-carrying channel. The photoelectric sensor transmits the arrival trigger signal to the controller, and the controller sends the start detection command to the vision detection component and the elastic detection component in sequence. S22, The vision detection component is triggered, and the backlight acquires an image of the tennis ball surface; S23. The controller controls the electric push rod of the elastic detection component to extend downward at a set speed, bringing the force sensor closer to the tennis ball surface. When the pressure value detected by the force sensor reaches the initial contact threshold... At that time, the force sensor sends a contact signal to the controller, and the controller records the contact time point. The electric actuator continues to extend downwards until the pressure value detected by the force sensor reaches the set maximum pressure. Record this time point. The controller controls the electric push rod to reset; S24. The controller calculates the residual elasticity index of the tennis ball based on the data collected by the force sensor. : ； Simultaneously, the tennis ball surface image is preprocessed, including image binarization, image downsampling compression, sliding window filtering, edge detection, and image enhancement, which are set sequentially to output a mask image. Then, the mask image is input into the pre-trained Stn-Dsc Net model to output the felt quality levels A, B, and C. S25, Based on the residual elasticity index value of tennis balls Calculating the overall evaluation index of tennis balls based on the quality level of felt : ； In the formula, and These represent the weighting coefficients for the elasticity index and the felt index, respectively. express The normalized value; This indicates the quality index value of tennis felt, and ; S26. Overall evaluation indicators The tennis grading results are obtained by comparing the results with the preset tennis grading thresholds.

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