Humanoid tea bud picker

Abstract

The invention discloses a humanoid tea bud picker, which relates to the technical field of tea leaf picking devices and comprises a clamping mechanism, a rotating mechanism, a tea bud collecting box and a motor damping system. The rear end of the clamping mechanism is provided with a 42 stepping motor, the front end of the motor is provided with a pair of gears with the tooth number ratio being 1: 2, the front end of the gear set is provided with a lead screw and a sliding block nut, the most front end of the clamping mechanism is provided with clamping fingers, the middle of the clamping fingers is provided with a picking blade, and the inner sides of the clamping fingers are pasted with flexible material sponges. The picker support is connected with the clamping fingers through the clamping finger arms and the external connecting pieces. The rotating mechanism is located below the clamping mechanism, and the tea bud collecting box is located at the rear end of the rotating mechanism. According to the humanoid tea bud picker, by simulating the action of pinching and rotating the wrist when the tea buds are manually picked, the integrity rate and picking efficiency of the tea buds are improved, and famous and high-quality tea is picked.

Description

Technical Field

[0001] The invention relates to the technical field of tea picking devices, in particular to a humanoid tea bud picking device. Background Art

[0002] As an economic crop, tea has a broad market prospect. The higher the quality of tea, the higher the price. Famous and high-quality tea is a general term for high-quality tea. Its picking standards include single bud, one bud and one leaf, and one bud and two leaves. China's tea planting area has basically increased year by year. Since tea picking is time-sensitive, most of the time it is necessary to pick all the tea within a few weeks. How to complete the picking task in time and prevent the planted tea from being abandoned in the tea garden is a problem. At this stage, there are two main picking methods: manual picking and mechanical picking. Famous and high-quality tea has high requirements for the completeness rate and quality of tea buds when picking, so it mainly relies on manual picking. With the rapid development of society, more and more young people are unwilling to stay in rural areas to engage in the hard industry of tea planting and production, resulting in a serious shortage of labor for tea picking. In addition, due to the short time and high labor intensity of tea picking, labor costs are gradually increasing. Although traditional mechanical picking has improved the picking efficiency, it cannot distinguish between tender buds and old leaves during picking, and it will also damage the tea trees, affecting the germination of new buds. It can only achieve the picking of bulk tea, but cannot achieve the picking of high-quality tea. Therefore, it is urgent to realize the mechanized picking of high-quality tea.

[0003] According to the working principle, tea bud pickers are mainly divided into: shear-based tea bud pickers and anthropomorphic tea bud pickers. The first method is to use the shear force of the blade to cut the tea buds from the stems of the tea tree. The shear-type tea bud picker has a very high picking efficiency because of its simple picking action. However, the tea buds will be damaged during the picking process, affecting the enzyme reaction inside the tea leaves and reducing the quality of the tea leaves. The second method is to imitate the human tea picking action to pick the tea buds, mainly simulating the rotation of the human wrist, using a smaller clamping force, and picking the tea buds without damaging them. The anthropomorphic tea bud picker has a high tea bud integrity rate, which effectively avoids the problem of shear-type tea bud pickers damaging tea buds, but due to the complexity of the picking action, its picking efficiency is greatly reduced compared with the shear-type picker.

[0004] Therefore, it is necessary to design a tea bud picking device to solve the problems referred to above. Summary of the invention

[0005] In view of the problems existing in the existing tea bud pickers, the purpose of the present invention is to provide a humanoid tea bud picker for picking high-quality tea, so as to solve the problem of damage to the tea buds during the picking process, so that the designed tea bud picker can improve the efficiency of tea bud picking while ensuring the integrity of the tea buds.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A humanoid tea bud picker, characterized in that it comprises a clamping mechanism, a rotating mechanism, a tea bud collecting box and a motor vibration reduction system. The clamping mechanism is connected to the rotating mechanism through a rotating component, the rotating mechanism is located below the clamping mechanism, and the tea bud collecting box is located at the rear end of the rotating mechanism.

[0008] Preferably, the rear end of the clamping mechanism is a 42 stepper motor, and the front end of the motor is a pair of gears with a gear ratio of 1 to 2. The 42 stepper motor is connected to the small gear, and the front end of the gear group is a lead screw and a slider nut. One end of the lead screw is connected to the large gear, and the other end is connected to the picker bracket. The lead screw is fixed in the middle position of the internal space of the picker bracket by a lead screw fixing component, and the screw hole in the middle of the slider nut is connected to the lead screw. The front end of the slider nut is a finger clamp arm, and the grooves at both ends of the slider nut are connected to the internal connecting piece, and the internal connecting piece is connected to the finger clamp arm. The front end of the finger clamp arm is a finger clamp, and the middle of the finger clamp is a picking blade. A flexible material sponge is pasted on the inside of the finger clamp, and the picker bracket is connected to the finger clamp through the finger clamp arm and the external connecting piece.

[0009] Preferably, the rotating mechanism is driven by a double-output shaft 57 stepping motor.

[0010] Preferably, there is a square space at the bottom of the tea bud collecting box, and the picked tea buds will fall into this space.

[0011] Preferably, the motor vibration reduction system includes a lithium battery pack, a TB6600 driver, a HPD980 driver, a DP100 CNC power supply, an STM32 single-chip microcomputer, and 42 and 57 stepper motors.

[0012] Preferably, the rotation of the 42 stepper motor drives the small gear to rotate, and then the large gear rotates accordingly, the lead screw connected to the large gear rotates, and the slider nut converts the rotational motion into translational motion, and the forward and backward translation of the slider nut enables the clamping fingers to complete the opening and closing motion.

[0013] Preferably, the motor control algorithm in the motor vibration reduction system selects a 5-segment algorithm in the S-type algorithm, and the acceleration is represented by a sine function.

[0014] It is known that the time T1 of the acceleration phase (0, t1) and the time T2 of the deceleration phase (t2, t3) are equal. During the operation of the stepper motor, the expression for the acceleration change is:

[0015]

[0016] Integrating equation (1) gives the following expression for velocity change:

[0017]

[0018] Integrating equation (2) yields the displacement expression:

[0019]

[0020] In formula (1), a m is the maximum acceleration, ω is the angular velocity, and v in formula (2) m is the maximum speed of the click operation. In formula (3), s1 represents the displacement distance of the motor during the acceleration phase (0, t1), and s2 represents the displacement distance of the motor during the uniform speed phase (t1, t2). Set the v of the 57 dual-axis stepper motor m When the time is at t1 / 2, the speed is 10rpm. From the speed formula, we can get a m =10ω, when the time of the acceleration section is determined, the value of ω can also be obtained, and then the a can be calculated m value.

[0021] Preferably, a picking method of a humanoid tea bud picker comprises the following steps:

[0022] First, the clamping finger at the front end of the picker approaches the tender tea leaves. When it is in the appropriate picking position, the controller outputs a signal to drive the 42 stepper motor. The stepper motor rotates to drive the gear set to rotate, and then the lead screw connected to the gear set rotates together. Then the slider nut converts the rotational motion of the lead screw into translational motion. Finally, other parts are used to gradually clamp the tender tea leaves. Then the 57 stepper motor works to make the clamping mechanism rotate as a whole. After rotating the clamping mechanism to the position above the tea bud collection box, the 42 stepper motor is driven to move in the opposite direction. The front clamping finger of the tea bud picker is released, so that the tea buds fall into the collection box. Then the 57 stepper motor is driven to move in the opposite direction to return the clamping mechanism to its original position. If you want to achieve continuous picking, just repeat the above operations.

[0023] In the above technical solution, the humanoid tea bud picker provided by the present invention has the following beneficial effects:

[0024] 1. The present invention designs a humanoid tea bud picker that imitates the action of manual picking. The tea bud picker consists of a clamping mechanism, a rotating mechanism, a tea bud collection box and a motor vibration reduction system. The function of the clamping mechanism is mainly to clamp the tea leaves, mainly by the clamping fingers and blades at the front end of the picker directly acting on the tender tea leaves. The rotating mechanism imitates the action of wrist rotation and lifting during manual picking. It is powered by a double-output shaft 57 stepper motor to drive the clamping mechanism to rotate and make the tea buds fall into the collection box. The function of the motor control system is to reduce the impact force generated during the operation of the motor, extend the service life of the parts, and improve the stability of the tea bud picking action and the tea bud picking efficiency.

[0025] 2. The reason why the motor control algorithm in the motor vibration reduction system of the present invention selects the 5-segment algorithm is that the 7-segment algorithm in the S-type algorithm can make the speed change very smooth during the operation of the motor and reduce the impact force. However, the disadvantage is that the algorithm is complex, the number of parameters and the amount of calculation are large, and higher requirements are placed on the performance of the hardware. Compared with the former, the 5-segment algorithm lacks the uniform acceleration segment in the acceleration stage and the uniform deceleration segment in the deceleration stage, and is slightly inferior to the 7-segment algorithm in terms of stability, but the complexity of the algorithm is reduced, the debugging and maintenance of the program are simpler, and the real-time performance is stronger while maintaining high precision, which is suitable for small embedded systems with limited resources. Therefore, the 5-segment algorithm is selected as the control algorithm of the stepper motor. Since the acceleration curves of the traditional 5-segment stepper motor control in the acceleration stage and the deceleration stage are not smooth enough, and the sine function not only has continuity itself, but also its derivative function is continuous everywhere, so the acceleration of the stepper motor in the present invention is represented by a sine function. The improved speed curve is continuous and smooth, without mutations and inflection points, which can make the motor run more smoothly, thereby improving the stability of the picking action of the tea bud picker and improving the picking efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the main structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the top view of the structure of the present invention;

[0028] Figure 3 It is a side view structural schematic diagram of the present invention;

[0029] Figure 4 It is a schematic diagram of the overall structure of the present invention;

[0030] Figure 5 It is a schematic diagram of acceleration and speed curves of the motor control algorithm of the present invention;

[0031] Reference numerals:

[0032] 1. Tea bud collection box; 2. 57 stepper motor fixed parts; 3. 57 stepper motor rotating parts; 4. 57 double-output shaft stepper motor; 5. Picker bracket; 6. Picker bracket fixed parts; 7. 42 stepper motor; 8. 42 stepper motor fixed parts; 9. Small gear; 10. Large gear; 11. Screw; 12. Screw fixed parts; 13. Slider nut; 14. Internal connecting piece; 15. Finger clamp arm; 16. External connecting piece; 17. Finger clamp; 18. Sponge; 19. Picking blade; 20. Acceleration curve of motor control algorithm; 21. Speed ​​curve of motor control algorithm. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] See also Figure 1-5 The present invention provides a humanoid tea bud picker, comprising a clamping mechanism, a rotating mechanism, a tea bud collecting box and a motor vibration reduction system. The clamping mechanism is connected to the rotating mechanism through a rotating component, the rotating mechanism is located below the clamping mechanism, and the tea bud collecting box is located at the rear end of the rotating mechanism.

[0035] like Figure 2 As shown, the rear end of the clamping mechanism is a 42 stepper motor 7, and the front end of the motor is a pair of gears with a gear ratio of 1 to 2. The 42 stepper motor 7 is connected to the small gear 9, and the front end of the gear set is a lead screw 11 and a slider nut 13. One end of the lead screw 11 is connected to the large gear 10, and the other end is connected to the picker bracket 5. The lead screw 11 is fixed in the middle position of the internal space of the picker bracket 5 by a lead screw fixing component 12, and the screw hole in the middle of the slider nut 13 is connected to the lead screw 11. The front end of the slider nut 13 is a finger clamp arm 15, and the grooves at both ends of the slider nut 13 are connected to the internal connecting piece 14, and the internal connecting piece 14 is connected to the finger clamp arm 15. The front end of the finger clamp arm 15 is a finger clamp 17, and the middle of the finger clamp 17 is a picking blade 19. In order to make the tea bud incision smooth and reduce the degree of damage to the tea bud, the picking blade is made of stainless steel with a thickness of 3mm and a blade angle of 30 degrees. Since the skin and muscle tissue on the fingers can pinch the tea buds without damaging them and reducing the quality of the tea leaves during manual picking, a flexible material such as sponge 18 is pasted on the inner side of the clamping finger 17 at the front end of the tea bud picker, which can prevent the tea buds from being squeezed and deformed excessively during the process of clamping the tender tea leaves, and play a certain buffering role. The picker bracket 5 is connected to the clamping finger 17 through the clamping finger arm 15 and the external connecting piece 16.

[0036] The rotating mechanism is driven by a double-shaft 57 stepper motor 4, imitating the feature of wrist rotation during manual picking. The rotation of the double-shaft 57 stepper motor 4 drives the entire clamping mechanism to rotate, thereby picking the tea buds and sending them into the collection box 1.

[0037] There is a square space at the bottom of the tea bud collecting box 1, and the picked tea buds will fall into this space. The reason why the collecting box adopts this square design is that the tea buds will not fall accidentally when the picking device is in a tilted state during picking.

[0038] The motor vibration reduction system includes a lithium battery pack, a TB6600 driver, an HPD980 driver, a DP100 CNC power supply, an STM32 microcontroller, 42 and 57 stepper motors. The driver has multiple functions in the control system. First, the driver divides the step angle of the stepper motor into 8 subdivisions, which improves the resolution of the motor, so that the motor can be positioned more accurately, improves the stability of the control system, and the tea bud picker can be more accurate and efficient when picking. Then the built-in detection circuit of the driver can prevent overvoltage and overcurrent, protect the motor from damage, and enhance the reliability of the system. Finally, the driver can control the rotation direction and speed of the motor, which is crucial for the motion control of the tea bud picker. The DP100 CNC power supply can adjust the output voltage and current to meet the power supply requirements of different peripherals. The microcontroller selected is the STM32F4 model, which is mainly responsible for outputting PWM waveforms and controlling motor speed.

[0039] The rotation of the stepper motor 7 drives the small gear 9 to rotate, and then the large gear 10 rotates accordingly, and the lead screw 11 connected to the large gear 10 rotates, and the slider nut 13 converts the rotational motion into translational motion, and the forward and backward translation of the slider nut 13 enables the clamping finger 17 to complete the opening and closing motion.

[0040] The motor control algorithm in the motor vibration reduction system selects 5-stage control. Since the acceleration curves of the traditional 5-stage stepper motor control are not smooth enough in the acceleration stage and the deceleration stage, a new motor control algorithm is designed in the present invention, such as Figure 5 As shown, the sine function is not only continuous in itself, but also its derivative function is continuous everywhere, so the acceleration is represented by the sine function. The improved speed curve 21 is continuous and smooth, without mutations and inflection points, which can make the motor run more smoothly.

[0041] It is known that the time T1 of the acceleration phase (0, t1) and the time T2 of the deceleration phase (t2, t3) are equal. During the operation of the stepper motor, the expression for the acceleration change is:

[0042]

[0043] Integrating equation (1) gives the following expression for velocity change:

[0044]

[0045] Integrating equation (2) yields the displacement expression:

[0046]

[0047] In formula (1), a m is the maximum acceleration, ω is the angular velocity, and v in formula (2) m is the maximum speed of the click operation. In formula (3), s1 represents the displacement distance of the motor during the acceleration phase (0, t1), and s2 represents the displacement distance of the motor during the uniform speed phase (t1, t2). Set the v of the 57 dual-axis stepper motor m When the time is at t1 / 2, the speed is 10rpm. From the speed formula, we can get a m =10ω, when the time of the acceleration section is determined, the value of ω can also be obtained, and then the a can be calculated m value.

[0048] The picking method of the tea bud picker comprises the following steps:

[0049] First, the clamping finger 17 at the front end of the picker approaches the tender tea leaves. When it is in a suitable picking position, the controller outputs a signal to drive the stepper motor 7 42. The stepper motor 7 rotates to drive the gear set to rotate, and then the lead screw 11 connected to the gear set also rotates together. Then the slider nut 13 converts the rotational motion of the lead screw into translational motion. Finally, the picker clamping finger 17 gradually clamps the tender tea leaves through other parts. Then the stepper motor 4 57 works to make the clamping mechanism rotate as a whole. After rotating the clamping mechanism to the position above the tea bud collection box 1, the stepper motor 7 42 is driven to move in the opposite direction, and the clamping finger 17 at the front end of the tea bud picker is loosened, so that the tea buds fall into the collection box 1. Then the stepper motor 4 57 is driven to move in the opposite direction to return the clamping mechanism to its original position. If you want to achieve continuous picking, just repeat the above operation.

[0050] The working principle of the tea bud picker is:

[0051] First, the tea bud picker is close to the tender shoots of tea leaves. When the tea stems are located in the middle of the front clamping fingers 17 during the picking period, the STM32F4 single-chip microcomputer initializes the internal timer and function pins, and then converts the speed unit from rpm to step / s. The reason for this conversion is that the reciprocal of the speed indicates how long it takes to advance each step. Since the step angle of the stepper motor is 1.8 degrees, and the driver is 8 subdivisions, it is only necessary to multiply the parameter 1600 / 60 to convert the speed unit. The Newton iteration method is used to calculate the time interval of the first step of the motor rotation by the displacement formula, and then the rotation speed of the motor at the first step is calculated by the speed formula. The subsequent reasoning obtains the time of each step, and then the single-chip microcomputer outputs the rotation direction and pulse signal of the motor, and drives the 42 stepper motors 7 to make the clamping mechanism pinch the tea bud stems. After the 42 stepper motors 7 are finished working, the double-output shaft 57 stepper motors 4 are driven in the same mode, so that the rotating mechanism drives the clamping mechanism to rotate, and the tea buds are picked. The content not described in detail in this specification belongs to the prior art known to professional and technical personnel in this field.

[0052] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A humanoid tea bud picking device, characterized in that: It comprises a clamping mechanism, a rotating mechanism, a tea bud collecting box and a motor vibration reduction system; the clamping mechanism is connected to the rotating mechanism through a rotating component, the rotating mechanism is located below the clamping mechanism, and the tea bud collecting box is located at the rear end of the rotating mechanism.

2. The humanoid tea bud picking device according to claim 1, characterized in that: The rear end of the clamping mechanism is a 42 stepper motor, and the front end of the 42 stepper motor is a gear set consisting of a pair of small gears and a large gear with a gear ratio of 1 to 2; the 42 stepper motor is connected to the small gear, and the front end of the gear set is a lead screw and a slider nut, one end of the lead screw is connected to the large gear, and the other end is connected to the picker bracket, and the lead screw is fixed in the middle position of the internal space of the picker bracket by a lead screw fixing component; the screw hole in the middle of the slider nut is connected to the lead screw; the front end of the slider nut is a finger clamp arm; the grooves at both ends of the slider nut are connected to the internal connecting piece, and the internal connecting piece is connected to the finger clamp arm; the front end of the finger clamp arm is a clamp finger, and the middle of the clamp finger is a picking blade, and a flexible material sponge is pasted on the inside of the clamp finger, and the picker bracket is connected to the clamp finger through the finger clamp arm and the external connecting piece.

3. The humanoid tea bud picking device according to claim 1, characterized in that: The rotating mechanism is driven by a double-output shaft 57 stepper motor.

4. The humanoid tea bud picking device according to claim 1, characterized in that: There is a square space at the bottom of the tea bud collecting box, and the picked tea buds will fall into this space.

5. The humanoid tea bud picking device according to claim 1, characterized in that: The motor vibration reduction system includes a lithium battery pack, a TB6600 driver, an HPD980 driver, a DP100 numerical control power supply, an STM32 single-chip microcomputer, and 42 and 57 stepper motors.

6. The humanoid tea bud picking device according to claim 2, characterized in that: The rotation of the stepper motor 42 drives the small gear to rotate, and then the large gear rotates accordingly, the lead screw connected to the large gear rotates, and the slider nut converts the rotational motion into translational motion. The forward and backward translation of the slider nut enables the clamping fingers to complete the opening and closing motion.

7. The humanoid tea bud picking device according to claim 1, characterized in that: The motor control algorithm in the motor vibration reduction system selects 5-stage control, and the acceleration is represented by a sine function; It is known that the time T1 of the acceleration phase (0, t1) and the time T2 of the deceleration phase (t2, t3) are equal. During the operation of the stepper motor, the expression for the acceleration change is: Integrating equation (1) gives the following expression for velocity change: Integrating equation (2) yields the displacement expression: In formula (1), a m is the maximum acceleration, ω is the angular velocity, and v in formula (2) m is the maximum speed of the click operation. In formula (3), s1 represents the displacement distance of the motor during the acceleration phase (0, t1), and s2 represents the displacement distance of the motor during the uniform speed phase (t1, t2). Set v of the 57 dual-axis stepper motor m is 20rpm; when the time is at t1 / 2, the speed is 10rpm, and the speed formula can be used to get a m =10ω, when the time of the acceleration section is determined, the value of ω can also be obtained, and then the a can be calculated m value.

8. A tea bud picking method using the humanoid tea bud picking device according to claim 1, characterized in that: The following steps are involved: First, the clamping fingers at the front end of the picker are close to the tender tea leaves. When they are in the appropriate picking position, the controller outputs a signal to drive the 42 stepper motor. The rotation of the stepper motor drives the gear set to rotate, and then the lead screw connected to the gear set also rotates together. Then the slider nut converts the rotational motion of the lead screw into translational motion, and finally the picker clamping fingers gradually clamp the tender tea leaves through other parts; then the 57 stepper motor works to make the clamping mechanism rotate as a whole. After rotating the clamping mechanism to the position above the tea bud collection box, the 42 stepper motor is driven to move in the opposite direction, and the clamping fingers at the front end of the tea bud picker are released, so that the tea buds fall into the collection box; then the 57 stepper motor is driven to move in the opposite direction to return the clamping mechanism to its original position; if you want to achieve continuous picking, just repeat the above operations.

Images