Liquid fertilizer zero-speed hole application robot based on eccentric crank slideway mechanism

Abstract

The invention discloses a liquid fertilizer zero-speed hole application robot based on an eccentric crank slideway mechanism. The liquid fertilizer zero-speed hole application robot comprises a rack, an automatic deviation correction walking system, a hole pricking system, a variable infusion system, a sensing feedback system and a control system. An eccentric crank slideway mechanism driven by a stepping motor drives a fertilizing needle to move, the effective length of a crank is equal to the radius of a wheel, and a control system is matched with motion parameters of the needle and the wheel in real time according to sensing feedback, so that the horizontal speed of the fertilizing needle relative to the ground at the moment when the fertilizing needle is inserted into soil is zero; therefore, zero-speed hole pricking and synchronous precise fertilizer injection are completed. The robot can effectively reduce the risk of soil disturbance and root damage, improves the precision and operation efficiency of liquid fertilizer deep application, and is especially suitable for efficient and energy-saving fertilization operation in dry farming.

Description

Technical Field

[0001] This invention belongs to the field of agricultural machinery technology, specifically relating to a liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism. Background Technology

[0002] Existing deep application of liquid fertilizer largely relies on manual labor or mobile fertilization machinery. While these machines can perform basic liquid fertilizer delivery and surface application during movement, they generally lack precise hole application and dynamic synchronous control capabilities. Traditional fertilization devices typically employ fixed or simple swing-type hole-punching structures. The punching needles exhibit significant horizontal speed relative to the ground during operation, easily leading to large soil disturbances, uneven hole openings, and even damage to crop roots, affecting fertilization effectiveness and crop growth. Furthermore, fertilization location often depends on manual visual inspection or mechanical positioning, making it difficult to adaptively align rows and accurately locate based on the real-time crop position, easily resulting in misaligned or missed applications of fertilizer. In the fertilizer delivery stage, the common top-discharge needle design is prone to soil clogging, affecting continuous liquid fertilizer injection. Summary of the Invention

[0003] This invention aims to provide a liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism, which solves the technical problems of existing fertilizer application machinery, such as large soil disturbance, high risk of root damage, and inaccurate fertilization position caused by the relative speed between the needle and the ground when making holes during movement.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism includes a frame, on which a fertilizer tank, an automatic deviation correction walking system, a hole-punching system, a sensor feedback system, a variable infusion system, and a control system are mounted. The automatic alignment walking system is used to drive the frame to move. It includes two sets of drive modules and four wheels. The four wheels are mounted on the bottom of the frame and the two sets of drive modules are used to drive the four wheels on the left and right sides to rotate respectively. The acupuncture system, installed on the front side of the frame, is used to perform acupuncture actions. It includes an eccentric crank slide mechanism driven by a stepper motor and a fertilizer needle installed on the eccentric crank slide mechanism. A variable infusion system for delivering liquid fertilizer includes a fertilizer tank, a variable pump, and a terminal fertilizer delivery tube connected to the fertilizer injection needle. The sensing feedback system is used to sense the working environment and status. It includes a grating light curtain sensor and a vision sensor for detecting the position of crops, and a pressure sensor for monitoring the resistance of hole drilling. The control system is connected to the automatic correction walking system, the puncture system, the variable infusion system, and the sensor feedback system respectively. The control system controls the motion parameters of the stepper motor based on the crop position information and the forward speed of the frame obtained by the sensor feedback system, so that the horizontal speed of the fertilizer needle relative to the ground is zero during the operation phase of puncturing the soil.

[0005] Furthermore, the eccentric crank slide mechanism includes a cross-shaped arm plate and a motor loading arm plate, which are fixed on the front side of the frame. The stepper motor is a dual-output shaft stepper motor, which is mounted on the motor loading arm plate. The main crank and the auxiliary crank are fixed on the two main shafts of the dual-output shaft stepper motor, respectively. A cross is rotatably mounted on the main crank. The cross is connected to the cross-shaped arm plate through four rocker arms. The rocker arms are connected to the cross and the cross-shaped arm plate by rotation. A vertical fertilizer channel is provided inside the cross. The terminal fertilizer delivery tube is connected to the upper end of the fertilizer channel through a needle tube. A fertilizer needle is connected to the lower end of the fertilizer channel. The terminal fertilizer delivery pipe is fitted with a connecting sleeve, a connecting rod is fixed to the connecting sleeve, a support rod is fixed to the auxiliary crank, and the ends of the connecting rod and the support rod are hinged together.

[0006] Furthermore, the acupuncture system is provided in two sets, which are arranged side by side on the front side of the frame.

[0007] Furthermore, in the sensing feedback system, two sets of grating light curtain sensors are arranged opposite each other on the left and right sides of the front of the frame to form a detection light curtain for accurately locating the position of the plant stem. The visual sensor is located in the middle of the front side of the frame and is used to identify crop rows and assist in navigation and correction. The pressure sensor is located at the lower end of the fertilization channel and is used to sense the soil resistance during the hole-making process in real time.

[0008] Furthermore, the variable infusion system also includes a pressure regulating filter installed on the inlet pipeline of the variable pump, and a solenoid valve installed on the syringe. The control system is further configured to: control the solenoid valve to open for precise fertilizer injection when the fertilizer needle moves to the lowest point of its trajectory.

[0009] Furthermore, the drive module includes a drive motor, a motor driver, a battery, and a dual-output shaft reducer. The dual-output shaft reducer is arranged in the front-to-back direction, and the two output shafts of the dual-output shaft reducer are respectively connected to the front and rear wheels through two bevel gear pairs. The drive motor is connected to the dual-output shaft reducer.

[0010] Furthermore, the frame is provided with an assembly slot for accommodating the fertilizer box and the drive module, and a heat dissipation box for heat dissipation corresponding to each assembly slot.

[0011] The control system includes a core processing unit, a storage unit, a communication module, a human-machine interaction unit, and a power management unit.

[0012] Compared with existing technologies, the beneficial effects of this invention are as follows: By adopting an eccentric crank slide mechanism and a closed-loop control strategy that integrates multiple sensors, this invention achieves "zero-speed hole drilling" and "precise deep application per row" during the deep application of liquid fertilizer. During the hole drilling stage, the horizontal speed of the needle relative to the ground is zero, which greatly reduces soil disturbance, avoids damage to crop roots, and improves the quality of operation. Through the coordinated positioning of vision and grating sensors, combined with an automatic deviation correction walking system, stable row-to-row operation can be achieved, ensuring accurate fertilization location. The side-discharge needle design and real-time pressure feedback control effectively prevent fertilizer blockage and can dynamically optimize the hole drilling trajectory based on soil resistance. The combination of the dual-row parallel operation design and the variable infusion system significantly improves operation efficiency and fertilizer utilization, adapting to the needs of large-scale and precision agricultural fertilization. Attached Figure Description

[0013] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is an isometric view of a liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to the present invention. Figure 2 This is an isometric view from another perspective of a liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to the present invention. Figure 3 An exploded view of the acupuncture point system; Figure 4 This is a schematic diagram of a variable infusion system; Figure 5 A schematic diagram showing the installation of the cross-shaped arm plate and the motor loading arm plate; Figure 6 This is a schematic diagram showing the location of the sensing feedback system. Detailed Implementation

[0014] 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.

[0015] The present invention will be further described in detail below with reference to the embodiments.

[0016] like Figure 1-6 As shown, the liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism of the present invention mainly includes a frame 1, a fertilizer tank 2, an automatic deviation correction walking system, a hole-planting system, a variable infusion system, a sensor feedback system, and a control system. The frame 1 is the main structural body of the entire device, used to install and support all other functional systems.

[0017] The automatic steering and walking system provides propulsion and enables automatic walking and steering correction. The system includes two drive modules and four wheels 8. The four wheels 8 are symmetrically mounted at the four corners of the bottom of the frame 1. Each drive module drives the two front and rear wheels 8 on the same side. Each drive module specifically includes a drive motor 9, a motor driver 10, a battery 11, and a dual-output shaft reducer 12. The dual-output shaft reducer 12 is arranged along the front-rear direction of the machine body, and its input end is connected to the output shaft of the drive motor 9. The two output shafts 13 of the dual-output shaft reducer 12 are respectively connected to the axles of the two front and rear wheels 8 on the same side through two bevel gear pairs, thereby transmitting power to the wheels. The battery 11 provides power to the drive motor 9 and other electrical equipment. When the control system detects a deviation in the travel path based on the sensor feedback system, it can control the differential operation of the left and right drive motors 9 to achieve automatic steering and steering correction of the machine body.

[0018] The hole-punching system is installed on the front side of the frame 1 and is used to perform zero-speed hole-punching action on the soil in the crop root zone during movement. In this embodiment, two sets of hole-punching systems are set up side by side symmetrically on the front side of the frame 1, which can simultaneously operate on two rows of crops. Each set of hole-punching systems includes an eccentric crank slide mechanism and a fertilizer needle 14. The eccentric crank slide mechanism mainly includes a cross-shaped arm plate 15, a motor loading arm plate 16, a dual-output shaft stepper motor 17, a main crank 18, a secondary crank 19, a cross 20, four rocker arms 21, and a linkage mechanism.

[0019] The cross-shaped arm plate 15 and the motor loading arm plate 16 are welded to the front side of the frame 1. A dual-output shaft stepper motor 17 is fixedly mounted on the motor loading arm plate 16. A main crank 18 and a secondary crank 19 are fixedly mounted on the two output shafts (main shafts) of the dual-output shaft stepper motor 17, respectively. The main crank 18 is rotatably connected to the center of the cross 20 via a hinge shaft. The straight-line distance between this hinge point and the main shaft of the dual-output shaft stepper motor 17 (i.e., the effective working length of the main crank 18) is equal to the radius of the wheel 8; this is a key mechanical design for achieving zero-speed acupuncture. The cross 20 is hinged at its four corners to one end of each of the four rocker arms 21, and the other ends of the four rocker arms 21 are hinged to the four endpoints of the cross-shaped arm plate 15, thus forming a planar parallel linkage mechanism. The function of this mechanism is to constrain the cross 20 (and the fertilizer needle 14 mounted on it) to maintain a vertical posture throughout complex spatial movements. The cross 20 has a vertically penetrating fertilizer channel inside. The fertilizer needle 14 is fixedly connected to the bottom of the cross 20 and communicates with the lower outlet of the fertilizer channel. The side wall of the fertilizer needle 14 has a fertilizer outlet, which can effectively prevent the soil from clogging the fertilizer outlet when drilling the hole.

[0020] The auxiliary crank 19, support rod 22, connecting rod 23, and connecting sleeve 24 sleeved on the terminal fertilizer delivery pipe together constitute a linkage mechanism that drives the terminal fertilizer delivery pipe 25 to move synchronously. Specifically, the connecting sleeve 24 is fixedly sleeved on the outer periphery of the terminal fertilizer delivery pipe 25 and is fixedly connected to one end of the connecting rod 23. The other end of the connecting rod 23 is hinged to the end of the support rod 22, while the root of the support rod 22 is fixed to the end of the auxiliary crank 19. When the dual-output shaft stepper motor 17 operates, the auxiliary crank 19 drives the connecting sleeve 24 and the terminal fertilizer delivery pipe 25 to move synchronously along the trajectory of the fertilizer needle 14 through this linkage mechanism, ensuring that the fertilizer delivery pipeline is not pulled or twisted during dynamic operation.

[0021] The variable displacement infusion system is used to precisely deliver liquid fertilizer from the fertilizer tank 2 to the fertilizer application needle 14. The system mainly includes the fertilizer tank 2, a variable displacement pump 26, a pressure regulating filter 27, a solenoid valve 28, and a terminal fertilizer delivery tube 25. The fertilizer tank 2 is fixed to the frame 1. The inlet of the variable displacement pump 26 is connected to the inside of the fertilizer tank 2 via a pipeline equipped with a pressure regulating filter 27, which stabilizes the delivery pressure and filters impurities. The outlet of the variable displacement pump 26 is connected to the terminal fertilizer delivery tube 25 via a drug delivery tube 101. The terminal fertilizer delivery tube 25 is connected to the upper inlet of the fertilizer application channel on the cross 20 via a flexible needle tube 100, on which a solenoid valve 28 is installed. The control system can precisely control the opening and closing timing of the solenoid valve 28, ensuring it only opens when the fertilizer application needle 14 reaches the lowest point of its trajectory (i.e., the deepest point of the acupuncture point), thus achieving precise deep application of liquid fertilizer.

[0022] The sensor feedback system is used to perceive the working environment and machine status in real time, providing a basis for decision-making in the control system. The system mainly includes two sets of grating light curtain sensors 29, a vision sensor 30, a pressure sensor 31, and a signal processor 32. The two sets of grating light curtain sensors 29 are arranged opposite each other on the left and right sides of the front of the frame 1, with their transmitting and receiving devices facing each other, forming one or more detection light curtains. When the crop stem passes through the light curtain, the system can accurately locate its lateral position. The vision sensor 30 is installed in the middle of the front side of the frame 1, facing forward and downward, and is used to identify crop rows, enabling navigation and row alignment assistance. The pressure sensor 31 is preferably installed at the root of the fertilizer needle 14 or at the connection point between the fertilizer needle and the cross 20, and is used to monitor the soil resistance to the needle during hole drilling in real time. The signal processor 32 is electrically connected to all the above sensors, responsible for collecting and initially processing the sensor signals, and then sending the processed information to the control system. The control system includes a core processing unit 34, a storage unit, a communication module 36, a human-machine interaction unit 37, and a power management unit 38.

[0023] The control system, the "brain" of the robot, is electrically connected to the automatic deviation correction walking system (specifically, the motor driver 10), the hole-punching system (specifically, the dual-axis stepper motor 17), the variable infusion system (specifically, the variable pump 26 and the solenoid valve 28), and the sensor feedback system (specifically, the signal processor 32). The core processing unit 34 of the control system, based on the crop position information and the robot's forward speed provided by the sensor feedback system, uses a precise algorithm to control the angular velocity of the dual-axis stepper motor 17, matching it with the angular velocity of the wheels 8 during the hole-punching stage. Since the length of the main crank 18 is equal to the wheel radius, when their angular velocities are consistent, the horizontal velocity of the fertilizer needle 14 relative to the ground is zero at the moment of penetration, achieving "zero-speed hole-punching" and greatly reducing disturbance to the soil and root system. Simultaneously, the control system also controls the walking system to perform real-time deviation correction based on signals from the vision sensor 30; dynamically fine-tunes the speed of the stepper motor based on signals from the pressure sensor 31 to optimize the hole-punching trajectory; and controls the solenoid valve 28 to open at the optimal time for fertilizer injection.

[0024] In addition, to ensure the stable operation of all electrical components, multiple assembly slots 33 are provided on the frame 1, which are used to house components such as the fertilizer tank 2, the battery 11, and the drive motor 9. At the assembly slots corresponding to heat-generating components such as the drive motor 9 and the control system, heat dissipation boxes 34 with ventilation windows are provided to provide effective heat dissipation.

[0025] The working process of this invention is briefly described as follows: The robot moves along the furrows, with the vision sensor 30 and the grating light curtain sensor 29 working together to locate the crops and ensure alignment. When the system determines that it has reached the fertilization location, the control system initiates the hole-punching program, controlling the dual-axis stepper motor 17 to insert the fertilization needle 14 into the soil at a predetermined depth at "zero speed." Simultaneously, the solenoid valve 28 is instantly opened, and the variable pump 26 injects a measured amount of liquid fertilizer into the deep soil through the terminal fertilizer delivery pipe 25. After fertilization is completed, the needle is lifted, and the robot moves to the next work point, thus repeating the cycle. Throughout the process, the pressure sensor 31 provides closed-loop feedback, continuously optimizing the control parameters.

[0026] It should be noted that, in this document, terms such as “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism, characterized in that: The system includes a frame, which is equipped with a fertilizer tank, an automatic deviation correction walking system, an acupuncture point system, a sensor feedback system, a variable infusion system, and a control system. The automatic alignment walking system is used to drive the frame to move. It includes two sets of drive modules and four wheels. The four wheels are mounted on the bottom of the frame and the two sets of drive modules are used to drive the four wheels on the left and right sides to rotate respectively. The acupuncture system, installed on the front side of the frame, is used to perform acupuncture actions. It includes an eccentric crank slide mechanism driven by a stepper motor and a fertilizer needle installed on the eccentric crank slide mechanism. A variable infusion system for delivering liquid fertilizer includes a fertilizer tank, a variable pump, and a terminal fertilizer delivery tube connected to the fertilizer injection needle. The sensing feedback system is used to sense the working environment and status. It includes a grating light curtain sensor and a vision sensor for detecting the position of crops, and a pressure sensor for monitoring the resistance of hole drilling. The control system is connected to the automatic correction walking system, the puncture system, the variable infusion system, and the sensor feedback system respectively. The control system controls the motion parameters of the stepper motor based on the crop position information and the forward speed of the frame obtained by the sensor feedback system, so that the horizontal speed of the fertilizer needle relative to the ground is zero during the operation phase of puncturing the soil.

2. The liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 1, characterized in that: The eccentric crank slide mechanism includes a cross-shaped arm plate and a motor loading arm plate, which are fixed on the front side of the frame. The stepper motor is a dual-output shaft stepper motor, which is mounted on the motor loading arm plate. The main crank and auxiliary crank are fixed on the two main shafts of the dual-output shaft stepper motor, respectively. A cross is rotatably mounted on the main crank. The cross is connected to the cross-shaped arm plate through four rocker arms. The rocker arms are connected to the cross and the cross-shaped arm plate by rotation. A vertical fertilizer channel is provided inside the cross. The terminal fertilizer delivery tube is connected to the upper end of the fertilizer channel through a needle tube. A fertilizer needle is connected to the lower end of the fertilizer channel. The terminal fertilizer delivery pipe is fitted with a connecting sleeve, a connecting rod is fixed to the connecting sleeve, a support rod is fixed to the auxiliary crank, and the ends of the connecting rod and the support rod are hinged together.

3. The liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 2, characterized in that: The acupuncture system is set up in two sets, which are arranged side by side on the front side of the frame.

4. The liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 1, characterized in that: In the sensing feedback system, two sets of grating light curtain sensors are arranged opposite each other on the left and right sides of the front of the frame to form a detection light curtain for accurately locating the position of the plant stem. The visual sensor is located in the middle of the front side of the frame and is used to identify crop rows and assist in navigation and correction. The pressure sensor is located at the lower end of the fertilization channel and is used to sense the soil resistance during the hole-making process in real time.

5. A liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 1, characterized in that: The variable infusion system also includes a pressure regulating filter installed on the inlet pipeline of the variable pump, and a solenoid valve installed on the syringe. The control system is further configured to: control the solenoid valve to open for precise fertilizer injection when the fertilizer needle moves to the lowest point of its trajectory.

6. The liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 1, characterized in that: The drive module includes a drive motor, a motor driver, a battery, and a dual-output shaft reducer. The dual-output shaft reducer is arranged in the front-to-back direction, and the two output shafts of the dual-output shaft reducer are respectively connected to the front and rear wheels through two bevel gear pairs. The drive motor is connected to the dual-output shaft reducer.

7. A liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 6, characterized in that: The frame is provided with an assembly slot for accommodating the fertilizer tank and the drive module, and a heat dissipation box for heat dissipation corresponding to each assembly slot.

8. A liquid fertilizer zero-speed hole application robot based on an eccentric crank slide mechanism according to claim 7, characterized in that: The control system includes a core processing unit, a storage unit, a communication module, a human-machine interaction unit, and a power management unit.

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