Volleyball Spiking Training Device and Control Method Based on Cable Tension Sensing

Abstract

This invention belongs to the field of volleyball training technology and discloses a volleyball spiking training device and its control method based on cable tension sensing. The device includes an actuator, a guide, a cable, and a suspension component. The actuator includes a housing, a drive assembly, a cable retraction and extension assembly, a control mechanism, a power supply unit, and a cable tension sensing mechanism. One end of the cable is connected to the cable retraction and extension assembly, and the other end hangs down through the guide and connects to the suspension component. The suspension component and the volleyball form a detachable connection. The control mechanism stores cable retraction and extension stroke parameters and determines the volleyball's hit and hang states based on the sensing signals: when the ball is hit, the cable of a length corresponding to the retraction and extension stroke is released, causing the suspension component to lower to the hang height; when the ball is re-hung, the corresponding length of cable is retracted, raising it to the spiking height. This invention automatically identifies the training state by utilizing changes in cable tension, driving the suspension component to automatically rise and fall between a preset hang height and spiking height, reducing manual operation and improving the continuity and convenience of training.

Description

Technical Field

[0001] This invention belongs to the field of volleyball training technology, specifically a volleyball spiking training device and its control method based on cable tension sensing. Background Technology

[0002] Spiking drills are an important part of volleyball instruction and specialized training. When practicing spiking, trainees need to repeatedly perform actions such as the approach run, jump, arm swing, hit the ball, and landing. Therefore, it is usually necessary to keep the volleyball stably at a suitable height for spiking to allow for repeated practice.

[0003] In existing training methods, some devices use ropes, elastic cords, supports, or fixed clamping structures to suspend the volleyball at a predetermined height. While these devices can reduce manual ball tossing or passing to some extent, they still have shortcomings in practical use: Firstly, the volleyball usually needs to be manually hoisted to a high position, or the trainee needs to repeatedly adjust the height of the volleyball manually, which is quite cumbersome; secondly, after being spiked, the volleyball is easily affected by the tension of the ropes, elastic cords, or fixed structures, resulting in a difference in flight trajectory and hitting feedback compared to a real spike.

[0004] Furthermore, while some electrically operated lifting training devices can raise and lower the volleyball using a motor, their control typically relies on manual buttons, remote control commands, or preset lifting times. This makes it difficult to automatically adjust the movement based on actual conditions during training, such as whether the volleyball is hit or re-attached, requiring significant manual intervention during continuous training. Therefore, it is necessary to provide a volleyball spiking training device and its control method that can reduce the difficulty of hanging the ball, improve spiking feedback, and automatically adjust the volleyball's hanging height according to the training status. Summary of the Invention

[0005] The purpose of this invention is to provide a volleyball spiking training device and its control method based on cable tension sensing, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a volleyball spiking training device based on cable tension sensing, comprising an actuator, a guide, a cable, and a suspension component;

[0007] The actuator includes a housing, a drive assembly, a cable take-up and release assembly, a control mechanism, a power supply unit, and a cable tension sensing mechanism. The drive assembly is driven to the cable take-up and release assembly, and the power supply unit is used to supply power to the drive assembly and the control mechanism.

[0008] The actuator and the guide maintain a defined relative position in use through the same support structure, external fixing structure or connecting structure;

[0009] One end of the cable is connected to the cable take-up and down assembly, and the other end of the cable leads out of the actuator, is guided by the guide and extends downward;

[0010] The suspension member is connected to the drooping end of the cable and is used to form a detachable suspension connection with the volleyball to be trained.

[0011] The cable tension sensing mechanism is used to acquire a sensing signal reflecting the cable tension state and send the sensing signal to the control mechanism;

[0012] The control mechanism is configured to: store or acquire cable retraction and extension stroke parameters that characterize the height difference between the hanging height and the spike height; determine the hit state of the volleyball to be trained separating from the suspension component and the hanging state of the volleyball to be trained reattaching to the suspension component based on the sensing signal.

[0013] When the knock-off state is determined to occur, the control mechanism controls the drive component to drive the cable retraction component to release the cable of a length corresponding to the cable retraction stroke parameter, so that the suspension component descends to the ball hanging height;

[0014] When the ball-hanging state is determined to occur, the control mechanism controls the drive component to drive the cable winding component to wind up the cable of a length corresponding to the cable winding stroke parameter, so that the suspension member and the volleyball to be trained hanging on the suspension member rise to the spike height.

[0015] The control method for a volleyball spiking training device based on cable tension sensing includes the following steps:

[0016] S1: Obtain height control parameters, including cable retraction / extraction stroke for moving the suspension between the hanging ball height and the snapping ball height;

[0017] S2: The control mechanism controls the actuator to rewind the cable according to the cable winding and unwinding stroke, so that the suspension member and the volleyball hanging on the suspension member are raised to the spike height;

[0018] S3: The cable tension sensing mechanism continuously acquires sensing signals reflecting the cable tension state and sends the sensing signals to the control mechanism;

[0019] S4: The control mechanism determines whether a first change has occurred, representing the separation of the volleyball from the suspension component after being spiked, based on the sensing signal; if the first change has not occurred, the process returns to step S; if the first change has occurred, the control mechanism controls the execution mechanism to release the cable length corresponding to the cable retraction stroke, causing the suspension component to descend to the height of the hanging ball.

[0020] S5: The cable tension sensing mechanism continues to acquire sensing signals reflecting the cable tension state and sends the sensing signals to the control mechanism;

[0021] S6: The control mechanism determines whether a second change has occurred, indicating that the volleyball has been reattached to the suspension member, based on the sensing signal; if the second change has not occurred, the process returns to step S5; if the second change has occurred, the control mechanism controls the actuator to rewind the cable length corresponding to the cable rewind stroke, so that the suspension member and the volleyball attached to the suspension member are raised to the spike height, and the process returns to step S3.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. This invention establishes a cable tension sensing mechanism within the cable tension transmission path or the electrical parameter detection path of the drive component, ensuring a stable cable path by maintaining a defined relative position between the actuator and the guide component during use. This allows the control mechanism to identify the state of the volleyball after separation from the suspension component and after reattaching the volleyball based on changes in cable tension, and accordingly control the actuator to rewind or unwind the cable. The control mechanism precisely controls the release and rewind lengths based on preset cable rewind and unwind stroke parameters, enabling the suspension component to automatically and accurately return to the hanging and spiking heights. This reduces the need for repeated manual raising and lowering or button control by trainees, improving the continuity and ease of use of volleyball spiking training.

[0024] 2. This invention forms a stable volleyball suspension path through a crossbar, guide member, cable, and suspension member, and establishes a single-point separable connection between the suspension member and the volleyball. This allows the volleyball to remain at a predetermined height when stationary and to detach from the suspension member and fly out when spiked. This structure reduces interference from the connection structure on the volleyball's flight trajectory and hitting feel, providing trainees with training feedback closer to actual spikes. Furthermore, the automatic lifting and lowering mechanism of the actuator reduces the difficulty of high-position ball suspension. Attached Figure Description

[0025] Figure 1 This is a schematic diagram showing the overall state of the present invention;

[0026] Figure 2 This is a schematic diagram showing the first embodiment of the actuator of the present invention.

[0027] Figure 3 This is a schematic diagram showing the second embodiment of the actuator of the present invention.

[0028] Figure 4 This is a schematic diagram showing the third embodiment of the actuator of the present invention;

[0029] Figure 5This is a block diagram of the overall system of the present invention.

[0030] In the diagram: 1. Actuator; 101. Housing; 102. Motor; 103. Cable reel; 104. Control mechanism; 105. Power supply unit; 106. Electrical parameter detection module; 107. Sensing mounting base; 108. Sliding component; 109. Sensing guide wheel; 110. Elastic element; 111. Deformation detection component; 112. Mounting plate; 2. Crossbar; 3. Column; 4. Guide component; 5. Cable; 6. Suspension component; 7. Volleyball; 8. Remote control; 9. Base. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The "cable tension sensing" described in this invention is not limited to directly setting a tension sensor to measure the tension of cable 5. It also includes methods that indirectly characterize the tension state of cable 5 by measuring the force, displacement, deformation, and switching state changes caused by changes in the tension of cable 5, or by measuring changes in electrical parameters such as the operating current, input power, back electromotive force, bus voltage ripple, and power switch voltage drop in the power supply circuit and drive circuit of motor 102. In other words, any sensing signal reflecting the tension state of cable 5 that can be acquired, and the control mechanism 104 can identify the unloading state of volleyball 7 after it has been knocked away and the loading state of volleyball 7 after it has been reattached based on the sensing signal, can be used as the cable tension sensing implementation method of this invention.

[0033] The commercially available models of electronic components, electric components, sensors, and communication components listed in this invention are only used to illustrate that this invention can be implemented using existing mature devices, and do not imply that this invention must use these specific models. Those skilled in the art can select commercially available devices with the same function or equivalent performance to replace them according to actual requirements such as power supply voltage, output torque, communication distance, sampling accuracy, and installation space.

[0034] Example 1: Overall Structure of Volleyball Spiking Training Device

[0035] like Figure 1 As shown, this embodiment provides a volleyball spiking training device based on cable tension sensing, including an actuator 1, a guide 4, a cable 5, a suspension 6, a remote controller 8, and a base 9.

[0036] The actuator 1 and the guide 4 maintain a defined relative position during use. This defined relative position can be achieved in various ways, such as by mounting the actuator 1 and the guide 4 on the same bracket or frame, or by directly fixing their relative positions using a connector.

[0037] In a preferred embodiment, a crossbar 2 and a column 3 can be provided. The column 3 is mounted on a base 9, which supports the column 3, allowing it to remain vertical or nearly vertical in the training area. The base 9 can be a tripod base, a weighted base, a foldable support base, or a movable base with casters and locking mechanisms. To improve stability, the base 9 can use a steel chassis, aluminum alloy legs, and rubber feet; alternatively, it can use a commercially available retractable training frame or retractable light stand base as its support.

[0038] The crossbar 2 is connected to the upper part of the upright 3 and extends outward from the upright 3, creating a lateral gap between the extended end or middle area of ​​the crossbar 2 and the upright 3, thereby forming a volleyball suspension space on one side of the upright 3. This volleyball suspension space is used to arrange the hanging section of the cable 5, the suspension component 6, and the volleyball 7, making it less likely for the trainee to be interfered with by the upright 3 when spiking the ball. The crossbar 2 can be a round tube, square tube, elliptical tube, or a profiled member with reinforcing ribs; aluminum alloy tubes or carbon steel tubes are preferred to balance weight and rigidity.

[0039] The crossbar 2 and the upright 3 are connected by a connecting structure. This connecting structure may include a sleeve fitted onto the upper end of the upright 3, a crossbar connecting part connected to the crossbar 2, and a locking element to restrict relative movement between the sleeve and the crossbar connecting part. The sleeve may be a sleeve, clamp, holding seat, or clip structure, fitted onto or clamping the upper part of the upright 3. The crossbar connecting part may be a plug tube, U-shaped seat, hinge seat, or clamp seat, with one end of the crossbar 2 inserted into the crossbar connecting part, or fixed to the crossbar connecting part by bolts, pins, snap-fits, or clamping screws. The locking element may be a hand-tightening screw, locking nut, quick-release lever, pin, or elastic positioning pin. With this structure, the crossbar 2 can remain fixed relative to the upright 3 during use, and can be disassembled or folded during storage or transportation.

[0040] In a preferred configuration, the connection structure includes a cylindrical sleeve fitted onto the top of the column 3, with radial locking screws on the sidewall of the sleeve. A crossbar connecting portion is located on the outer side of the sleeve, and this crossbar connecting portion is a connector adapted to the outer diameter of the crossbar 2. One end of the crossbar 2 is inserted into the connector and locked in place by a through bolt. This structure allows the crossbar 2 to maintain a stable cantilevered state relative to the column 3, reducing interference caused by the crossbar 2's swaying during spiking training on the tension recognition of the cable 5.

[0041] A guide member 4 is mounted on the crossbar 2 to limit the downward position of the cable 5 within the volleyball suspension space. The guide member 4 includes a guide mounting seat and a cable guide portion mounted on the guide mounting seat. The guide mounting seat can be sleeved on the outer periphery of the crossbar 2, clamped to the outer periphery of the crossbar 2, or tightly held to the outer periphery of the crossbar 2, or fixed to the crossbar 2 by screws, bolts, or rivets. To facilitate adjustment of the lateral position of the volleyball 7, the guide mounting seat can be movable along the length of the crossbar 2 and locked by locking screws or clamps after moving to a predetermined position. The cable guide portion can be a low-friction cable guide ring, a guide hole with a low-friction bushing, an anti-derailment guide wheel, a fixed pulley, or a closed cable guide seat. The cable guide portion has a limiting part to prevent the cable 5 from laterally slipping out, such as an annular closed hole, a U-shaped groove fitting baffle, an anti-derailment wheel rim, or a covered cable guide seat.

[0042] In this embodiment, the guide component 4 preferably adopts a split clamp mounting base and an anti-derailment guide wheel. The clamp mounting base consists of two semi-annular clamping parts, which are fastened to the crossbar 2 by bolts; the anti-derailment guide wheel is mounted on the clamp mounting base via an axle, and the cable 5 extends downward after passing through the anti-derailment guide wheel. Since the anti-derailment guide wheel can reduce the frictional resistance of the cable 5 during the winding and unwinding process, and at the same time restrict the lateral slippage of the cable 5, it can improve the winding and unwinding stability of the cable 5 and reduce the risk of abnormal sensing signals caused by the cable 5 jumping out of the groove.

[0043] The actuator 1 is mounted on the column 3 and located below the crossbar 2. The actuator 1 is preferably mounted at a low or mid-low position on the column 3, allowing training personnel to easily maintain it and avoiding the problem of excessively long cable paths and interference with the ground or support legs when the actuator 1 is placed on the ground. The actuator 1 can be fixed to the column 3 using clamps, grips, U-clamps, bolt clamps, or quick-release brackets. The housing 101 of the actuator 1 can be made of ABS plastic, nylon, aluminum alloy, or sheet metal. The housing 101 has a cable outlet, which can be equipped with a rubber protective ring, ceramic cable guide sleeve, nylon guide sleeve, or roller guide to reduce wear on the cable 5 when it enters and exits the actuator 1.

[0044] One end of cable 5 is connected to the cable take-up assembly in actuator 1, and the other end extends upward along column 3 after being led out from actuator 1, and then downward after being guided by guide member 4 on crossbar 2. The drooping end of cable 5 is connected to suspension member 6, which is used to form a detachable suspension connection with volleyball 7. Cable 5 can be steel wire rope, nylon rope, Kevlar fiber rope, braided rope, plastic-coated steel wire rope, or abrasion-resistant flat tape. In this embodiment, cable 5 is preferably made of plastic-coated steel wire rope or high-strength nylon braided rope with a diameter of 1.0mm to 2.5mm to balance flexibility, strength, and abrasion resistance.

[0045] The suspension element 6 may include a connecting ring, hanging ring, hook, carabiner, swivel joint, flexible connecting strap, or detachable connecting medium. The suspension element 6 is connected to the drooping end of the cable 5 and forms a single-point detachable connection with the connecting part on the volleyball 7.

[0046] In this embodiment, the suspension member 6 can be a commercially available small carabiner, key ring, universal swivel ring, or ring-shaped connecting buckle; the outer surface of the volleyball 7 is provided with a connecting part, which can be a rough-surface patch, hook patch, magnetic piece, soft connecting piece, tearable patch, or detachable clamping piece of a hook-and-loop fastener. Preferably, the suspension member 6 is provided with a hook patch or connecting buckle, and the surface of the volleyball 7 is provided with a rough-surface patch; both can bear the weight of the volleyball 7 when it is suspended at rest, and can detach when the volleyball 7 is hit. The principle for selecting the connection force is: greater than the gravitational force generated when the volleyball 7 is suspended at rest, and less than the instantaneous dynamic force generated when the trainee hits the volleyball 7 normally. As a quantitative example, for a standard adult volleyball (weighing about 260-280 grams), the static holding force of the single-point detachable connection can be set between 3 Newtons and 15 Newtons. This range ensures that the volleyball will not accidentally fall off under slight shaking, and also ensures reliable separation when subjected to normal hitting force.

[0047] In this embodiment, no separate counterweight is provided. The weight of the volleyball 7 itself is sufficient to provide stable tension for the cable 5 when the ball is suspended. When the volleyball 7 is spiked and separated from the suspension member 6, the tension of the cable 5 decreases significantly compared to the suspended state, and the control mechanism 104 can identify the knock-off state through this change in tension. The suspension member 6 itself can be a metal ring or a connecting buckle with a certain weight, so that when the actuator 1 releases the cable 5, the suspension member 6 can naturally droop to the height of the suspended ball under the action of gravity. If the suspension member 6 is relatively light, the actuator 1 can also release the cable at a lower speed, and the weight of the suspension member 6 and the flexibility of the cable 5 can be used to make it descend, without the need to add a separate counterweight under the volleyball 7.

[0048] The remote controller 8 is used for wireless communication with the control mechanism 104 in the actuator 1. The remote controller 8 can be equipped with buttons, a display screen, a ranging module, or a wireless transmission module. The remote controller 8 can be used to input the spike height, or to measure or input the hanging height. In one implementation, the remote controller 8 has a built-in VL53L0X or VL53L1X time-of-flight ranging module. The trainee places the remote controller 8 on the ground or a predetermined reference surface, aligns it with the connection position of the suspension piece 6 or the volleyball 7, and measures the distance to obtain the reference position height. The control mechanism 104 determines the cable retraction / extension stroke based on the reference position height and the spike height. Communication between the remote controller 8 and the control mechanism 104 can be achieved using a 2.4GHz wireless module, Bluetooth module, Wi-Fi module, or 433MHz wireless module.

[0049] Example 2: Structure of the first embodiment of the actuator

[0050] like Figure 2 As shown, in this embodiment, the actuator 1 includes a housing 101, a motor 102, a cable reel 103, a control mechanism 104, and a power supply unit 105. The motor 102 serves as a drive component, and the cable reel 103 serves as a cable winding and unwinding component. The motor 102 and the cable reel 103 are connected in a driving connection. One end of the cable 5 is wound around the cable reel 103, and the cable reel 103 winds up or unwinds the cable 5 as the motor 102 rotates.

[0051] Motor 102 can be a commercially available DC geared motor, stepper motor, or servo motor. To reduce costs and obtain sufficient low-speed output torque, motor 102 is preferably a 12V DC geared motor, such as the JGA25-370 type DC geared motor, JGB37-520 type DC geared motor, N20 geared motor, or a commercially available DC geared motor with equivalent performance. If higher position control accuracy is required, motor 102 can also be a DC geared motor with an encoder, such as a JGA25-370 encoder motor with a Hall encoder or a 37GB series encoder geared motor. If a stepper motor is used, motor 102 can be a 42BYGH series stepper motor or a 28BYJ-48 stepper motor; the specific model can be determined based on the load of cable 5 and the diameter of cable reel 103.

[0052] The cable reel 103 can be a reel, a spool, a winding disc, or a drum structure with flanges. Flanges are provided at both ends of the cable reel 103, and the cable 5 is wound between the two flanges to prevent the cable 5 from laterally unwinding from the cable reel 103. The cable reel 103 can be connected to the output shaft of the motor 102 via a shaft hole, or it can be connected to the motor 102 via a coupling, gear set, worm gear, or synchronous pulley. When the motor 102 rotates forward, the cable reel 103 winds up the cable 5; when the motor 102 rotates in reverse, the cable reel 103 unwinds the cable 5; when the motor 102 stops, the control mechanism 104 can maintain the position of the cable reel 103 through motor braking, drive axle short-circuit braking, worm gear self-locking, pawl locking, or motor braking.

[0053] The control mechanism 104 is housed within the housing 101 and is used to receive height information sent by the remote controller 8, process cable tension sensing signals, and control the movement of the motor 102. The control mechanism 104 can be implemented using a commercially available microcontroller development board or control module, such as an Arduino Nano development board, an ESP32-WROOM-32E control module, an STM32F103C8T6 minimum system board, a Raspberry Pi Pico control board, or an embedded controller with equivalent performance. If direct Bluetooth or Wi-Fi communication between the remote controller 8 and the actuator 1 is required, the control mechanism 104 preferably uses an ESP32-WROOM-32E control module; if an independent wireless receiver module is used, the control mechanism 104 can use an Arduino Nano or an STM32F103C8T6 minimum system board.

[0054] The drive circuit of motor 102 can use commercially available DC motor drive modules, such as the DRV8871 DC motor drive module, DRV8833 dual H-bridge motor drive module, TB6612FNG dual-channel motor drive module, L298N motor drive module, or equivalent motor drive modules. When using a 12V DC geared motor, the DRV8871 DC motor drive module is preferred, as it can meet the forward and reverse rotation control requirements of common low-power DC geared motors. The control mechanism 104 controls the motor drive module through PWM signals or direction control signals, causing motor 102 to retract or unwind the wire at a preset speed.

[0055] The power supply unit 105 supplies power to the motor 102, control mechanism 104, cable tension sensing mechanism, and wireless communication module. The power supply unit 105 can use a lithium battery pack, rechargeable power bank, DC adapter, or replaceable dry cell battery pack. For ease of outdoor training, the power supply unit 105 preferably uses a 2-cell or 3-cell 18650 lithium battery pack, along with a BMS protection board, step-down module, and charging interface. For example, a 2S 7.4V or 3S 11.1V lithium battery pack can be used, supplying power to the 5V control system via an XL4015 or LM2596 step-down module, while simultaneously supplying power to the motor 102 directly or via the drive module. The power supply unit 105 may also include a power switch, charging interface, undervoltage detection circuit, and fuse to improve safety.

[0056] In this embodiment, the trainee inputs the spike height via remote control 8, or measures the hanging height of the ball via remote control 8 and inputs the spike height. Control mechanism 104 determines the cable rewind / unwind stroke based on height control parameters. The height control parameters can be the cable rewind / unwind length directly, or the height difference between the reference position height and the spike height. Control mechanism 104 controls motor 102 to drive cable reel 103 to rewind or unwind the cable 5 to a length corresponding to the cable rewind / unwind stroke, causing the suspension member 6 and the volleyball 7 to switch between the hanging height and the spike height.

[0057] Example 3: Structure of the second embodiment of the actuator

[0058] like Figure 3 As shown, in this embodiment, the signal acquisition unit of the cable tension sensing mechanism includes an electrical parameter detection module 106. The electrical parameter detection module 106 is connected to the power supply circuit or drive circuit of the motor 102 and is used to detect electrical parameters that change with the tension of the cable 5. These electrical parameters may include the operating current of the motor 102, input power, back electromotive force, bus voltage ripple of the motor drive bridge, on-state voltage drop of the power switch, or internal current limiting signal of the drive module.

[0059] In one implementation, the electrical parameter detection module 106 uses a commercially available INA219 current / voltage detection module. The INA219 current / voltage detection module is connected in series in the power supply branch of the motor 102, capable of detecting the supply current and voltage of the motor 102 during operation, and sending the detection data to the control mechanism 104 via the I²C bus. The control mechanism 104 determines the load change of the cable 5 based on the current change during the operation of the motor 102. When the volleyball 7 is connected to the drooping end of the cable 5 via the suspension member 6, the cable 5 bears the weight of the volleyball 7 and the weight of the suspension member 6, resulting in a higher load current for the motor 102 during reeling or holding. When the volleyball 7 is struck and separated from the suspension member 6, the load on the cable 5 decreases, and the operating current or holding current of the motor 102 decreases, thereby identifying the knockback state.

[0060] In another implementation, the electrical parameter detection module 106 uses a commercially available ACS712 Hall effect current sensor module or ACS758 current sensor module. This type of current sensor module is installed in the power supply circuit of the motor 102 and outputs an analog voltage signal corresponding to the operating current of the motor 102. The control mechanism 104 samples this analog voltage signal via an ADC to obtain the operating current variation curve of the motor 102. To improve the stability of the judgment, the control mechanism 104 can perform moving average, median filtering, or low-pass filtering on the sampled signal to remove interference caused by motor commutation, brush noise, and transient impacts.

[0061] It should be noted that when the volleyball is stably suspended at the spiking height and the motor is stationary, if the motor drive bridge is in a high-resistance state or the motor is not in a controlled holding state, the motor operating current may be zero or close to zero. In this case, it is difficult to directly sense sudden changes in cable tension through changes in operating current. To enable the electrical parameter detection module to obtain electrical characteristics that can be used to determine the cable tension state during the stationary suspension phase, this embodiment can employ at least one of the following methods:

[0062] First, the control mechanism enables the motor drive module and outputs a low duty cycle PWM signal to the motor, causing the motor to generate a small holding torque to maintain cable tension. The duty cycle of the low duty cycle PWM signal is limited to not causing significant lifting or lowering of the suspension component. When the volleyball is separated from or reattached to the suspension component, the cable load changes, and the motor holding current, input power, or drive circuit voltage characteristics change accordingly. The control mechanism identifies the change in cable tension state based on this.

[0063] Second, the control mechanism controls the motor to perform a short-term tensioning action according to a preset detection cycle. The short-term tensioning action is a slight winding action in the winding direction, and its duration and displacement are limited to a range that does not change the volleyball training height or affect the training state. During the short-term tensioning action, the control mechanism collects the motor operating current, input power or drive circuit voltage characteristics, and judges the cable tension state based on the peak value, average value or trend of the electrical parameters.

[0064] Third, the motor adopts a servo motor with torque feedback or current feedback output, or a stepper drive system with closed-loop current detection function. The control mechanism judges the change in cable tension by reading or acquiring the current feedback signal, torque feedback signal or driver feedback signal corresponding to the holding torque.

[0065] The above method can be used alone or in conjunction with an electrical parameter detection module to obtain a sensing signal that reflects the cable tension state when the cable is in a static suspended or low-speed winding and unwinding state.

[0066] In another implementation, the motor drive module uses a DRV8871 DC motor drive module. The control mechanism 104 can use the current regulation, current limiting, or motor terminal voltage change information of the drive module as an indirect basis for judging the tension state. Alternatively, the control mechanism 104 can detect the back electromotive force at both ends of the motor 102, the voltage ripple of the drive bridge bus, or the on-state voltage drop of the power switch, and use the relationship that changes in the external load will cause changes in the motor's electrical parameters to indirectly characterize the tension change of the cable 5.

[0067] Specifically, during initialization or the first ball attachment, the control mechanism 104 collects electrical parameters for a period of time while the volleyball 7 is stably attached to the suspension member 6, and calculates its average value or characteristic value as a reference tension characteristic value. Thereafter, the control mechanism 104 continuously collects electrical parameters. When the electrical parameters change below the hit-out judgment threshold relative to the reference tension characteristic value for a first predetermined time, the control mechanism 104 determines that the volleyball 7 has been spiked and separated from the suspension member 6; when the electrical parameters change above the ball attachment judgment threshold relative to the no-ball or low-load state for a second predetermined time, the control mechanism 104 determines that the volleyball 7 has been reattached to the suspension member 6. The first and second predetermined times can be set according to the sampling frequency and training state, for example, set to 100ms to 1000ms.

[0068] To filter out high-frequency interference caused by motor brush commutation noise and suspension oscillation, the control mechanism 104 collects electrical parameters, such as operating current. At that time, a hybrid filtering algorithm combining moving average filtering and first-order lag filtering is adopted. Specifically, the current value after moving average filtering is:

[0069] in, The sliding window size is preferably set to 10-20; For the current number The instantaneous current value is obtained for each sampling period. Then, a first-order hysteresis filter is used to obtain the final sensing current characteristic value. :

[0070] in, For the filter coefficients, the preferred value range is 0.1. 0.3. When establishing the reference tension characteristic value, the control mechanism 104 calculates the average steady-state current under the stable connection state of the volleyball. The first threshold for determining the knockback state. The calculation is performed using the dynamic proportional shift method:

[0071]

[0072] in, This is a typical proportionality factor (usually 0.4-0.7) representing the weight of the volleyball in the total load. This is the margin compensation value for the fluctuation of the system's mechanical resistance. When and duration When the time is (preferably 150ms-300ms), it can be accurately determined that the volleyball 7 has separated from the suspension part 6.

[0073] The advantage of this embodiment is that cable tension sensing does not require an additional tension sensor connected in series with cable 5, nor does it require changes to the structure of suspension 6. Instead, it uses changes in electrical parameters caused by load variations in motor 102 for status identification. Therefore, this embodiment can reduce structural complexity, reduce the weight of the suspension end, and facilitate the design of the actuator 1 as a compact, integrated module.

[0074] Example 4: The third embodiment of the actuator structure

[0075] like Figure 4 As shown, in this embodiment, the signal acquisition unit of the cable tension sensing mechanism includes a sensing base 107, a sliding member 108, a sensing guide wheel 109, an elastic element 110, a deformation detection element 111, and a mounting plate 112. The mounting plate 112 is disposed inside the housing 101, the sensing base 107 is disposed on the mounting plate 112, the sliding member 108 is movably disposed on the sensing base 107, the sensing guide wheel 109 is disposed on the sliding member 108 and cooperates with the cable 5, the elastic element 110 is used to apply an elastic biasing force to the sliding member 108, and the deformation detection element 111 is used to detect the displacement of the sliding member 108, the deformation of the elastic element 110, or the position state of the sliding member 108 and output a sensing signal.

[0076] In this embodiment, the cable 5 is wound around or abuts the sensing guide wheel 109. When the cable 5 bears the weight of the volleyball 7, the cable 5 exerts a lateral force on the sensing guide wheel 109, causing the slider 108 to move relative to the sensing fixing seat 107 against the elastic force of the elastic element 110. When the volleyball 7 is hit and separated from the suspension member 6, the tension of the cable 5 decreases, and the elastic element 110 pushes the slider 108 back to its original position. The change in the position of the slider 108 reflects the change in the tension state of the cable 5.

[0077] The elastic element 110 can be a compression spring, tension spring, torsion spring, sheet spring, or rubber elastic block. The sensing mounting base 107 can be provided with a guide groove, guide post, or slide rail, and the sliding member 108 moves along the guide groove, guide post, or slide rail. The sensing guide wheel 109 can be a grooved roller, nylon wheel, bearing wheel, or ceramic cable guide wheel to reduce friction between the cable 5 and the sensing guide wheel 109. The mounting plate 112 can be a metal plate, plastic plate, fiberglass board, or a mounting boss inside the housing 101.

[0078] Displacement of slider 108 Real-time tension of cable 5 There is a strict mechanical correspondence between them. Let the wrap angle of cable 5 around the sensing guide wheel 109 be . The component of the cable tension generated in the sliding direction of the slider 108 is Under ideal conditions where friction of the guide wheel is negligible, the following force balance relationship exists:

[0079]

[0080] The elastic element 110 provides a reverse elastic force in this direction ,in The stiffness coefficient of elastic element 110, This is the initial preload.

[0081] When the volleyball is attached, the cable tension is... At this point, the elastic element is compressed to a displacement. ,satisfy:

[0082]

[0083] When the volleyball is hit, the cable tension drops sharply. The elastic element pushes the slider back to its displacement. During this process, the deformation detection component 111 only needs to be set in and Within the stroke range, the attenuation of the analog tension can be accurately converted into a switching change. This quantitatively designed structure greatly reduces the requirements for spring selection and sensor installation accuracy.

[0084] The deformation detection element 111 can be a microswitch, a Hall sensor, a displacement sensor, a photoelectric sensor, or a potentiometer. In one specific implementation, the deformation detection element 111 uses an Omron SS-5GL or a commercially available microswitch with equivalent performance, and the microswitch is positioned on the movement path of the slider 108. When the slider 108 moves to the trigger position while the volleyball is in the attached state, the microswitch outputs a first switching state; when the volleyball 7 is knocked away and the slider 108 returns to its original position, the microswitch outputs a second switching state. The control mechanism 104 identifies the knocked-away state or the attached-ball state by detecting the direction and duration of the switch state transitions.

[0085] In another specific implementation, the deformation detection element 111 uses an A3144 Hall switch, an SS49E linear Hall sensor, or a commercially available Hall sensor with equivalent performance, and a magnet is mounted on the slider 108. When the slider 108 moves with the change in cable tension 5, the relative distance between the magnet and the Hall sensor changes, and the Hall sensor outputs a switching signal or an analog signal. The control mechanism 104 determines the tension state of the cable 5 based on the jump or amplitude change of the Hall signal.

[0086] In another specific implementation, the deformation detection element 111 employs a linear potentiometer, a sliding potentiometer, or a photoelectric displacement sensor. The sliding element 108 is connected to the potentiometer slider or a light-shielding plate. When the sliding element 108 moves, the potentiometer output voltage or the photoelectric sensor output state changes. The control mechanism 104 obtains the displacement of the sliding element 108 based on the output signal and uses this displacement as an indirect representation of the tension state of the cable 5.

[0087] The advantage of this embodiment is that changes in cable tension are amplified and converted through mechanical displacement or elastic deformation, allowing the control mechanism 104 to obtain relatively intuitive switching or analog signals. Compared to purely electrical parameter detection methods, this embodiment has less dependence on the model of the motor 102 and the drive circuit, making it particularly suitable for application scenarios where changes in motor operating current are not significant or where electrical noise is high.

[0088] Example 5: Remote Control Height Setting and Travel Determination Method

[0089] In this embodiment, the remote controller 8 is wirelessly connected to the control mechanism 104. The remote controller 8 is used to measure, acquire, or input a reference position height, and is also used to input the spike height. The reference position height can be understood as the height at which the suspension member 6 is positioned when the trainee can easily hook the volleyball 7, or as the height of the suspension member 6 relative to the ground or a predetermined reference plane when it is in the ball-hooking position. The spike height is the desired height of the volleyball 7 for the trainee to perform a spike.

[0090] The remote controller 8 can be a commercially available wireless remote control module with a display screen, or it can be a custom-made control board. Specifically, the remote controller 8 may include an ESP32-WROOM-32E control module, buttons, an OLED display screen, a lithium battery, a charging module, and a ranging module. The ranging module can be a VL53L0X or VL53L1X time-of-flight ranging module; wireless communication can use the Bluetooth or Wi-Fi built into the ESP32 module, or it can use an nRF24L01, HC-05 Bluetooth module, HC-12 wireless serial port module, or a 433MHz wireless transmitter module.

[0091] In one usage scenario, the trainer first controls the actuator 1 to release the cable, lowering the suspension member 6 to a position suitable for hanging the ball. The trainer places the remote controller 8 on the ground and aligns the ranging module with the connection point of the suspension member 6 or the volleyball 7. The remote controller 8 measures the height of the suspension member 6 from the ground and uses this as the reference position height. Subsequently, the trainer inputs the spike height via the remote controller 8, which then sends the reference position height and the spike height to the control mechanism 104. The control mechanism 104 determines the cable retraction / release stroke based on the difference between the spike height and the reference position height and stores it as the cable retraction / release stroke parameter.

[0092] In another usage method, the trainee does not use the ranging module, but directly inputs the hanging height and spike height via remote control 8. The control mechanism 104 determines the cable retraction / deployment stroke based on the difference between the two. Alternatively, the remote control 8 only inputs the target spike height, and the control mechanism 104 calculates the cable retraction / deployment stroke based on the pre-calibrated initial hanging height. Both methods enable the suspension component 6 to move between the hanging height and the spike height.

[0093] To avoid discrepancies between the actual winding and unwinding length of the cable reel 103 and its theoretical length, the control mechanism 104 can determine the actual cable winding and unwinding stroke based on the rotation time of the motor 102, the encoder pulse count of the motor 102, the number of rotations of the cable reel 103, or the limit detection signal. For example, when the motor 102 is a DC geared motor with a Hall encoder, the control mechanism 104 can calculate the rotation angle of the cable reel 103 based on the encoder pulse count, and then convert the effective winding diameter of the cable reel 103 into the winding and unwinding length of the cable 5.

[0094] The control mechanism 104 converts the encoder pulse count into the actual cable winding and unwinding length. The specific conversion model is as follows:

[0095]

[0096] in, The cumulative number of pulses read by the control mechanism; This refers to the basic pulse count per revolution of the motor encoder. This represents the reduction ratio of the motor.

[0097] It should be noted that, This is the effective winding diameter of the cable reel 103 in its current winding state. Since the cable 5 may have multiple layers of winding on the cable reel 103, a diameter compensation algorithm is preset in the control mechanism 104.

[0098]

[0099] in, The initial effective winding diameter, The outer diameter of the cable. This is the current number of cabling layers (calculated from the cumulative pulse count).

[0100] If the motor 102 does not have an encoder, the control mechanism 104 can determine the take-up and take-down length by using the pre-calibrated take-up and take-down speed and running time.

[0101] Example 6: Single-point detachable suspension connection structure

[0102] In this embodiment, a connecting part is provided on the volleyball 7, and the suspension member 6 is connected to the connecting part at a single point for separability. The connecting part can be located on the top area of ​​the outer surface of the volleyball 7, and can be a hook and loop fastener, a soft patch, a magnetic piece, a snap fastener, or a flexible connecting piece. In order not to significantly affect the hitting feel of the volleyball 7, the connecting part is preferably made of a flexible material and is set on the outer surface of the volleyball 7 by sewing, bonding, heat pressing, adhesive application, or strapping.

[0103] The suspension component 6 may include a connecting ring, a hook, a carabiner, a swivel joint, and a detachable connecting medium. The swivel joint is used to reduce the torsional force on the cable 5 when the volleyball 7 rotates in the suspended state; the connecting ring is used to connect to the cable 5; and the detachable connecting medium is used to connect to the connecting part on the volleyball 7. For example, the suspension component 6 may adopt a combination structure of a small metal swivel ring and nylon webbing, with hook-and-loop fasteners at the lower end of the nylon webbing and loop fasteners on the outer surface of the volleyball 7, forming a detachable connection after they are attached together.

[0104] When the volleyball 7 is suspended at rest, the connecting force between the connecting part and the suspension member 6 can withstand the weight of the volleyball 7, keeping it stably at the predetermined height. When the trainee spikes the volleyball 7, the instantaneous impact force causes the connecting part to detach from the suspension member 6, allowing the volleyball 7 to fly freely. Because the volleyball 7 separates from the cable 5 after being spiked, the cable 5 will not continuously pull on the volleyball 7 like a traditional elastic rope or fixed suspension rope, allowing the trainee to obtain flight feedback that is closer to the real spiking state.

[0105] The connection strength between the connecting part and the suspension part 6 can be adjusted by selecting the contact area of ​​the hook and loop fastener, the magnetic force of the magnetic attractor, the elasticity of the buckle, or the clamping force. For youth training or beginner training, the connection force can be set lower to ensure that the volleyball 7 can easily detach; for adults or trainees with greater strength, the connection force can be appropriately increased to prevent the volleyball 7 from accidentally detaching when not being spiked.

[0106] Example 7: Cooperative Control Method

[0107] like Figure 5 As shown, the present invention also provides a control method for a volleyball spiking training device based on cable tension sensing. This control method can be executed by a control mechanism 104, which controls the actuator 1 to rewind or unwind the cable 5 according to the sensing signal output by the cable tension sensing mechanism, thereby realizing a closed-loop training process of hanging the ball, lifting, hitting the ball, returning, and then hanging the ball again.

[0108] Specifically, the control method includes the following steps.

[0109] S1: Obtain height control parameters. Height control parameters include the cable retraction / detraction stroke for moving the suspension 6 between the ball-hanging height and the spike height. The cable retraction / detraction stroke can be input by the remote controller 8 or calculated by the control mechanism 104 based on the reference position height and the spike height. For example, the trainee measures the ball-hanging height using the remote controller 8 as follows: Enter the spiking height. The control mechanism 104 calculates the height difference between the two as the cable retraction / deployment stroke.

[0110] S2: Control mechanism 104 controls actuator 1 to rewind cable 5 according to the cable winding and unwinding stroke, so that suspension member 6 and volleyball 7 attached to suspension member 6 are raised to the spike height. During the lifting process, control mechanism 104 can control motor 102 to wind up the cable at a first speed; when approaching the spike height, control mechanism 104 can reduce the speed of motor 102 to reduce the swaying of volleyball 7.

[0111] S3: The cable tension sensing mechanism continuously acquires sensing signals reflecting the tension state of cable 5 and sends the sensing signals to the control mechanism 104. When the volleyball 7 is attached to the suspension member 6 and is at the spike height, the cable 5 is in a stable loading state, and the sensing signal is within the first stable range.

[0112] S4: The control mechanism 104 determines whether a first change has occurred, indicating that the volleyball 7 has separated from the suspension member 6 after being spiked, based on the sensing signal. The first change may be that the sensing signal drops from a first stable range to below the knockback judgment threshold and remains there for a predetermined time, or it may be that a switch signal changes to indicate an unloading state. When the first change occurs, the control mechanism 104 determines that the volleyball 7 has been knocked away and separated from the suspension member 6.

[0113] S5: If the control mechanism 104 determines that the first change has occurred, the control actuator 1 releases the cable 5 for the length corresponding to the cable retraction / release stroke, causing the suspension member 6 to descend to the height of the hanging ball. During the descent, since the volleyball 7 has separated from the suspension member 6, the weight of the suspension member 6 itself and the flexibility of the cable 5 cause the suspension member 6 to descend with the cable 5. The control mechanism 104 can cause the motor 102 to release the cable at a low speed to avoid excessive slack in the cable 5 or excessive swinging of the suspension member 6.

[0114] S6: The cable tension sensing mechanism continues to acquire sensing signals reflecting the tension state of cable 5 and sends these signals to the control mechanism 104. When the suspension member 6 is at the ball-hanging height and the volleyball 7 is not attached, cable 5 is under low load, and the sensing signal is within the second stable range. After the trainee reattaches the volleyball 7 to the suspension member 6, the tension of cable 5 increases, and the sensing signal changes.

[0115] S7: The control mechanism 104 determines whether a second change has occurred, indicating that the volleyball 7 has been reattached to the suspension member 6, based on the sensing signal. The second change can be that the sensing signal rises from the second stable range to above the reattachment judgment threshold and remains there for a predetermined time, or it can be that the switch signal changes, indicating a loading state. When the second change occurs, the control mechanism 104 determines that the volleyball 7 has been reattached to the suspension member 6, and controls the actuator 1 to rewind the cable 5 by the length corresponding to the cable rewind / unwind stroke, raising the suspension member 6 and the volleyball 7 attached to the suspension member 6 to the spike height, and then returns to step three to enter the next training cycle.

[0116] Through the above process, trainees no longer need to manually control the raising and lowering of the ball repeatedly during training. They only need to complete the spiking and re-attaching actions, and the device can automatically determine the spiking and re-attaching states based on the tension of cable 5, and automatically complete the descent and elevation. This control logic can reduce the involvement of training assistants and improve the efficiency of continuous spiking training.

[0117] Example 8: Setting Control Parameters and Thresholds

[0118] To improve the reliability of status judgment, the control mechanism 104 can establish a reference tension characteristic value during the initialization process. The reference tension characteristic value can be the average value of the sensing signal collected when the volleyball 7 is stably attached to the suspension member 6, or it can be the low-load signal characteristic value collected when the volleyball 7 is not attached and only the suspension member 6 is at the drooping end of the cable 5. The control mechanism 104 can simultaneously save the ball-attached reference value and the ball-free reference value, and automatically set the knockback judgment threshold and the ball-attached judgment threshold based on the difference between the two.

[0119] For example, when the electrical parameter detection module 106 detects the operating current of the motor 102, the control mechanism 104 collects the average current I1 of the motor 102 when it is in the volleyball 7 connected state, and collects the average current I0 when the volleyball 7 is not connected. A current change that is a certain proportion and close to I0 is considered a knockback state, and the current will rise from near I0 to close to I0. The change in current is determined to be a hanging ball state. To avoid misjudgment, the control mechanism 104 can also require the change to continue for a predetermined time, or require that multiple consecutive samples meet the threshold condition.

[0120] When an elastic bias-type state sensing structure is adopted, the control mechanism 104 can make judgments based on the on / off state of the micro switch, the output level of the Hall sensor, or the output amplitude of the displacement sensor. If the slider 108 is in the first position when the volleyball 7 is hooked, and returns to the second position after the volleyball 7 is hit, the change from the first position to the second position can be used as the basis for judging the hit state, and the change from the second position to the first position can be used as the basis for judging the hooking state.

[0121] The control mechanism 104 can also be configured with anti-shake processing, timeout protection, and abnormal protection. Anti-shake processing is used to filter out false triggers caused by short-term vibration; timeout protection is used to stop waiting or enter a low-power mode if the ball-hanging state is not detected within a predetermined time; abnormal protection is used to stop the motor 102 when the cable 5 is stuck, the motor 102 is stalled, the current is abnormally increased, or the voltage of the power supply unit 105 is too low, and prompt the user to check the device via the remote control 8 or indicator lights.

[0122] Example 9: Optional Implementation Combination Examples

[0123] The following is an example of a prototype combination. This combination is merely an embodiment and does not constitute a limitation on the scope of protection of this invention.

[0124] The control mechanism 104 of actuator 1 uses an ESP32-WROOM-32E control module. Motor 102 uses a JGA25-370 12V DC geared motor. The cable winding assembly uses a nylon reel 103 with an outer diameter of approximately 30mm to 50mm. The motor drive module uses a DRV8871 DC motor drive module. The power supply unit 105 uses a 3S11.1V 18650 lithium battery pack with a 3SBMS protection board, and outputs 5V to the control mechanism 104 via an LM2596 or XL4015 step-down module. The electrical parameter detection module 106 uses an INA219 current / voltage detection module, connected to the power supply branch of motor 102, and communicates with the control mechanism 104 via an I²C bus. The remote control 8 consists of an ESP32-WROOM-32E control module, a VL53L0X ranging module, a 0.96-inch OLED display, and a button module.

[0125] In another prototype assembly, the control mechanism 104 uses an Arduino Nano development board, the motor 102 uses a JGB37-520 DC geared motor, the motor drive module uses a TB6612FNG or DRV8871, the electrical parameter detection module 106 uses an ACS712-5A Hall current sensor module, and the remote controller 8 uses a 433MHz wireless transmitter / receiver module to transmit altitude parameters. This assembly is suitable for low-cost implementations that do not require Bluetooth or Wi-Fi communication.

[0126] In another prototype assembly, the cable tension sensing mechanism adopts... Figure 4The elastic bias structure shown employs an Omron SS-5GL microswitch or an A3144 Hall effect switch for deformation detection element 111, a compression spring for elastic element 110, and a nylon grooved wheel for sensing guide wheel 109. Changes in cable tension 5 cause the slider 108 to move, resulting in a switching signal output from the microswitch or Hall effect switch. This combination is suitable for implementations that aim to reduce the complexity of electrical sampling algorithms and use simple switching signals to determine the knockback and ball-hanging states.

[0127] Working principle and usage process of this invention:

[0128] In actual use, the trainer first places the upright 3 and base 9 on the training ground, fixes the crossbar 2 to the upper part of the upright 3, and adjusts the position of the guide 4 on the crossbar 2 so that the suspension position of the volleyball 7 is suitable for the trainer's approach run and jump spike. Then, the power to the actuator 1 is turned on, the control mechanism 104 completes self-test and establishes wireless communication with the remote controller 8.

[0129] The trainer uses remote control 8 to control actuator 1 to release the cable, causing suspension member 6 to descend to a suitable height for hanging the ball. The trainer then attaches the volleyball 7 to suspension member 6 via the connecting part. Remote control 8 acquires or inputs the hanging height and the spiking height. After control mechanism 104 determines the cable rewinding and unwinding stroke, it controls motor 102 to drive reel 103 to rewind cable 5, causing volleyball 7 to rise to spiking height.

[0130] The trainee completes the approach run, jump, and spike. After being spiked, the volleyball 7 separates from the suspension member 6 and flies out, causing a change in the tension of the cable 5. The cable tension sensing mechanism converts this change into a sensing signal and sends it to the control mechanism 104. Upon recognizing the "flying" state, the control mechanism 104 controls the actuator 1 to release the cable 5 to a length corresponding to the cable retraction / release parameters, causing the suspension member 6 to descend to the ball-hanging height. After the trainee retrieves the volleyball 7 and reattaches it to the suspension member 6, the tension of the cable 5 changes again. Upon recognizing the ball-hanging state, the control mechanism 104 automatically controls the actuator 1 to rewind the cable 5 to a length corresponding to the cable retraction / release parameters, causing the volleyball 7 to rise back to the spiking height, thus initiating the next round of spiking training.

Claims

1. A volleyball spiking training device based on cable tension sensing, characterized in that: Includes actuator (1), guide (4), cable (5) and suspension (6); The actuator (1) includes a housing (101), a drive assembly, a cable take-up and release assembly, a control mechanism (104), a power supply unit (105), and a cable tension sensing mechanism. The drive assembly is connected to the cable take-up and release assembly in a transmission manner, and the power supply unit (105) is used to supply power to the drive assembly and the control mechanism (104). The actuator (1) and the guide (4) maintain a defined relative position in use through the same support structure, external fixing structure or connecting structure; One end of the cable (5) is connected to the cable take-up and take-down assembly, and the other end of the cable (5) leads out of the actuator (1), is guided by the guide (4) and extends downward; The suspension member (6) is connected to the drooping end of the cable (5) and is used to form a detachable suspension connection with the volleyball to be trained. The cable tension sensing mechanism is used to acquire a sensing signal reflecting the tension state of the cable (5) and send the sensing signal to the control mechanism (104). The control mechanism (104) is configured to: store or acquire cable retraction and extension stroke parameters that characterize the height difference between the hanging height and the spike height, and determine the flying state of the volleyball to be trained separated from the suspension (6) and the hanging state of the volleyball to be trained reattached to the suspension (6) according to the sensing signal. When the knock-off state is determined to occur, the control mechanism (104) controls the drive assembly to drive the cable retraction assembly to release the cable (5) of a length corresponding to the cable retraction stroke parameter, so that the suspension member (6) descends to the hanging ball height; When the hanging state is determined to occur, the control mechanism (104) controls the drive component to drive the cable winding component to wind up the cable (5) of the length corresponding to the cable winding stroke parameter, so that the suspension member (6) and the volleyball to be trained hanging on the suspension member (6) rise to the spike height.

2. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: It also includes a crossbar (2), and the guide (4) is disposed on the crossbar (2).

3. The volleyball spiking training device based on cable tension sensing according to claim 2, characterized in that: It also includes a column (3), the crossbar (2) is connected to the upper part of the column (3) and extends outward to form a volleyball suspension space on one side of the column (3); the actuator (1) is installed on the column (3) and located below the crossbar (2).

4. The volleyball spiking training device based on cable tension sensing according to claim 3, characterized in that: The column (3) is mounted on the base (9); the crossbar (2) is connected to the upper part of the column (3) through a connecting structure, the connecting structure including a sleeve part sleeved on the upper end of the column (3), a crossbar connecting part connected to the crossbar (2), and a locking member for restricting the relative movement of the sleeve part or the crossbar connecting part.

5. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: The drive assembly includes a motor (102), and the cable winding assembly includes a reel (103). The motor (102) is connected to the reel (103) in a drive connection, and the cable (5) is wound around the reel (103). The control mechanism (104) is located inside the housing (101) and is used to control the motor (102) to rotate forward, reverse, or stop, so that the reel (103) can wind up, unwind, or hold the cable (5).

6. The volleyball spiking training device based on cable tension sensing according to claim 5, characterized in that: The cable tension sensing mechanism includes an electrical parameter detection module (106), which is connected to the power supply circuit or drive circuit of the motor (102) and is used to detect electrical parameters that change with the tension of the cable (5); the electrical parameters include at least one of the operating current, input power or back electromotive force of the motor (102).

7. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: The cable tension sensing mechanism includes a mounting plate (112), a sensing base (107), a sliding member (108), a sensing guide wheel (109), an elastic element (110), and a deformation detection element (111). The sliding member (108) is movably mounted on the sensing base (107), the sensing guide wheel (109) is mounted on the sliding member (108) and cooperates with the cable (5), and the elastic element (110) is used to apply an elastic bias force to the sliding member (108). The deformation detection element (111) is used to detect the displacement or position state of the sliding member (108) and output the sensing signal.

8. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: The guide member (4) includes a guide mounting seat and a wire guide portion disposed on the guide mounting seat; the wire guide portion is at least one of a low-friction wire guide ring, a guide hole with a low-friction bushing, an anti-slip guide wheel, a fixed pulley or a closed wire guide seat, and has a limiting portion for restricting the lateral dislodgement of the cable (5).

9. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: It also includes a remote controller (8), which is wirelessly connected to the control mechanism (104); the remote controller (8) is used to measure, acquire or input the reference position height, and is used to input the spike height; the control mechanism (104) is used to calculate the height difference based on the spike height and the reference position height, and to determine the cable take-up and release stroke parameters based on the height difference and control the take-up stroke or release stroke of the cable take-up and release assembly.

10. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: The volleyball is provided with a connecting part, and the suspension member (6) and the connecting part form a single-point separable connection; the single-point separable connection is configured to: maintain the connection when the volleyball is suspended at rest, and separate the volleyball from the suspension member (6) when the volleyball is hit.

11. The volleyball spiking training device based on cable tension sensing according to claim 1, characterized in that: The control mechanism (104) is configured to: when the sensing signal is an analog signal, compare the amplitude of the sensing signal with a preset threshold; if the sensing signal changes below the knock-out judgment threshold and continues for a predetermined time, determine that the knock-out state has occurred; if the sensing signal changes above the ball-hanging judgment threshold and continues for a predetermined time, determine that the ball-hanging state has occurred; when the sensing signal is a digital signal, monitor the direction and duration of the switching of the sensing signal, and output the corresponding release command or reel-in command according to the first switching representing the knock-out state and the second switching representing the ball-hanging state.

12. A control method for a volleyball spiking training device based on cable tension sensing, characterized in that, The volleyball spiking training device based on cable tension sensing as described in any one of claims 1 to 11 is characterized by comprising the following steps: S1: Obtain height control parameters, the height control parameters including cable retraction stroke for moving the suspension (6) between the hanging ball height and the hook ball height; S2: The control mechanism (104) controls the actuator (1) to wind up the cable (5) according to the cable winding and unwinding stroke, so that the suspension member (6) and the volleyball attached to the suspension member (6) are raised to the spike height; S3: The cable tension sensing mechanism continuously acquires sensing signals reflecting the tension state of the cable (5) and sends the sensing signals to the control mechanism (104). S4: The control mechanism (104) determines whether a first change has occurred, representing the separation of the volleyball from the suspension member (6) after being spiked, based on the sensing signal; if the first change has not occurred, the process returns to step S3; if the first change has occurred, the control mechanism (104) controls the execution mechanism (1) to release the cable (5) length corresponding to the cable retraction stroke, so that the suspension member (6) descends to the height of the hanging ball; S5: The cable tension sensing mechanism continues to acquire sensing signals reflecting the tension state of the cable (5) and sends the sensing signals to the control mechanism (104). S6: The control mechanism (104) determines whether a second change has occurred, representing the volleyball being reattached to the suspension member (6), based on the sensing signal; if the second change has not occurred, it returns to step S5; if the second change has occurred, the control mechanism (104) controls the execution mechanism (1) to rewind the cable (5) length corresponding to the cable rewinding stroke, so that the suspension member (6) and the volleyball attached to the suspension member (6) are raised to the spike height, and returns to step S3.

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