Seedling conveying machine based on GPS navigation and automatic deviation correction control method of seedling conveying machine

Abstract

The invention discloses a seedling conveyor based on GPS navigation and an automatic deviation correction control method of the seedling conveyor, and belongs to the technical field of intelligent agricultural machinery. The seedling conveyor is jointly composed of a rack, a conveyor belt motor, a seedling tray conveyor belt, a steering wheel set, a GPS positioning module and a control system; the deviation between the actual track and the virtual track point is calculated in real time, and the output frequency of the motor is adjusted, so that automatic deviation correction is realized, and if the deviation exceeds a set threshold value, the running frequency of the wheel leg motor is automatically adjusted to ensure that equipment runs along a preset path. Compared with a traditional fixed rail type seedling conveying mechanism, the seedling conveying mechanism can be flexibly dispatched among different operation fields, accurate seedling conveying operation is achieved, and the problems that a fixed rail type seedling conveying mechanism is poor in flexibility and high in cost are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of smart agricultural machinery, and relates to a seedling transporter and a control method for the seedling transporter, and specifically to a seedling transporter based on GPS navigation and an automatic deviation correction control method for the seedling transporter. Background Art

[0002] With the continuous development of agricultural automation technology, especially in the fields of precision agriculture and smart agriculture, the demand for precise control of agricultural equipment is gradually increasing. As one of the important equipment in agricultural machinery, the seedling transporter is mainly used for the transportation of seedling trays in farmland. In the prior art, the seedling transporter generally adopts fixed tracks or manual transportation for path guidance, mainly to transport seedling trays in the seedling field. The traditional method is to build tracks, manually transport the seedling trays to the conveyor belt and transfer them to the seedling transport vehicle, and move to the next field after one field is moved.

[0003] The existing technology usually relies on preset fixed tracks for navigation. The limitations and defects in actual use are as follows: (1) The use of fixed tracks is easily restricted by factors such as terrain and soil conditions. Especially in farmlands with complex or irregular terrain, fixed tracks have poor adaptability and are difficult to cope with dynamic changes in the farmland environment. For example, seasonal changes in crop growth and rain erosion may affect the stability of the track, and thus affect the driving accuracy of the equipment. Changes in terrain or irregular soil conditions may cause the equipment to fail to operate normally or even deviate from the path. (2) Fixed track systems require a large amount of upfront investment, including track laying, debugging and maintenance. This not only increases the initial investment cost of the equipment, but also requires a long construction period, reducing the timeliness of agricultural production. In addition, once the track is damaged or the farmland needs to be renovated, the system needs to be rebuilt or adjusted on a large scale, which has poor flexibility. Summary of the invention

[0004] The purpose of the present invention is to propose a seedling transporter and an automatic correction control method for the seedling transporter based on GPS navigation in view of the shortcomings of the prior art such as high requirements on terrain and soil operating conditions, high investment and maintenance costs, long construction period, poor adaptability and low operating accuracy. Through high-precision positioning and real-time correction, it can flexibly respond in complex terrain, solve the problems of high cost, low adaptability and low flexibility of fixed tracks, and can further improve operating accuracy, reduce energy and maintenance costs, and enhance the efficiency and intelligence level of agricultural production.

[0005] The seedling transporter based on GPS navigation provided in this application adopts the following technical solutions:

[0006] The seedling conveyor based on GPS navigation comprises a frame, a conveyor belt motor arranged on the frame, and a seedling tray conveyor belt connected by the conveyor belt motor; characterized in that the seedling conveyor further comprises:

[0007] The steering wheel group is connected to the frame and consists of a steering front wheel and a steering rear wheel. The steering wheel group drives the frame and the seedling tray conveyor belt to change the position and angle direction;

[0008] A GPS positioning module A, connected to the steering front wheel;

[0009] A GPS positioning module B, connected to the steering rear wheel;

[0010] The control system is connected and fixed to the frame and consists of a GPS receiver, a deviation correction and solution terminal, and a steering wheel motor;

[0011] The GPS positioning module A and the GPS positioning module B are connected to the GPS receiver and feed data back to the deviation correction and solution terminal. The deviation correction and solution terminal is connected to the steering wheel motor control, and the steering wheel motor drives the steering wheel group to change and adjust the position and angle.

[0012] By adopting the above technical solution, dynamic correction is performed by calculating the deviation between the actual trajectory and the virtual track point in real time. If the deviation exceeds the set threshold, the operating frequency of the steering wheel motor is automatically adjusted to ensure that the equipment travels along the preset path.

[0013] Furthermore, the steering wheels in the steering wheel group are all independently driven steering wheels.

[0014] By adopting the above technical solutions, the steering accuracy and flexibility are improved, the mechanical structure is simplified, the complexity is reduced, the dynamic response capability is better, the turning radius and operating efficiency are increased, and the dependence on complex terrain is reduced, which can effectively improve the performance of the mobile seedling transporter in terms of precise control, flexible response to complex terrain, reduced mechanical complexity and improved operating efficiency. This design not only increases the automation and intelligence level of the seedling transporter, but also improves the adaptability and reliability of the equipment in actual agricultural operations.

[0015] The automatic deviation correction control method for the seedling conveyor provided in this application adopts the following technical scheme:

[0016] The automatic deviation correction control method of the seedling conveyor is characterized in that the automatic deviation correction control method comprises:

[0017] Position deviation calculation, angle deviation calculation, position deviation adjustment, angle deviation adjustment, motor frequency adjustment;

[0018] The method for calculating the position deviation comprises the following steps:

[0019] (1-1) Coordinate system establishment: An xy axis coordinate system is established on the travel path of the seedling transporter, wherein the y axis is parallel to the travel direction of the seedling transporter, the x axis is perpendicular to the travel direction of the seedling transporter, and a certain position on the x axis is set as the starting position or reference point; in this coordinate system, the coordinate point (x a ,y a ), obtain the coordinate point (x b ,y b ); The midpoint of the mobile seedling conveyor is taken as the position of the trajectory point, marked as Q j , Q j =(x j ,y j ), Q j The calculation formula is: Q j is the actual trajectory point;

[0020] (1-2) Using the virtual track data of the mobile seedling transporter, we can obtain the virtual track point set P virtual = {P1, P2, ..., P n}, each virtual orbit point P k The coordinates of (x k ,y k );

[0021] (1-3) Use the deviation correction and solution terminal to obtain each actual track point Q of the mobile seedling transporter j The coordinates of (x j ,y j );

[0022] (1-4) For each actual trajectory point Q j , calculate its difference with the virtual orbit point set P virtual The Euclidean distance d of each point in jk , select the virtual track point P with the smallest distance nearest , calculate the deviation Δx between the actual trajectory point and the selected virtual trajectory point j and Δy j ;

[0023] (1-5) According to the deviation Δx j and Δy j , calculate the position deviation

[0024] The method for calculating the angle deviation comprises the following steps:

[0025] (2-1) Calculate the adjacent virtual track points P on the virtual track k and P k+1 The slope m virtual ,

[0026] (2-2) Calculate the adjacent actual track points Q on the actual track j and Q j+1 The slope m actual ,

[0027] (2-3) Calculate the angle deviation Δθ between the actual track slope and the virtual track slope j , the calculation formula is:

[0028] Δθ j =arctan(m actual )-arctan(m virtual );

[0029] (2-4) According to the calculated deviation Δd j and Δθ j , generating an adjustment signal to the deviation correction and solution terminal, driving the rotating wheel motor through the control system, and the steering wheel motor drives the steering wheel to adjust the driving position or (and) angle of the seedling transporter so that the actual track is as close to the virtual track as possible;

[0030] The method for position deviation adjustment comprises the following steps:

[0031] (3-1) The displacement deviation is corrected by adjusting the movement of the seedling transporter wheel legs along the x-axis (and) or y-axis direction. The adjustment formula is: Δx adjust =k displacement ·Δx j ;

[0032] Δy adjust =k displacement ·Δy j ;

[0033] Among them, k displacement is the displacement adjustment factor;

[0034] (3-2) For displacement deviation Δx adjust , Δy adjust Design PID controllers separately:

[0035]

[0036] Among them, F y It is used to control the frequency difference between the left and right motors to correct the tendency of the seedling conveyor to deviate from the target point; K p , K i , K d They represent the proportional, integral and differential coefficients in the PID controller respectively;

[0037] The method for adjusting the angle deviation comprises the following steps:

[0038] (4-1) By calculating the difference between the actual track slope and the virtual track slope, the angle adjustment amount θ is generated. adjust , the angle adjustment calculation formula is:

[0039] θ adjust =k angle ·Δθ j ;

[0040] Among them, k angle is the angle adjustment factor;

[0041] (4-2) For the angle deviation Δθ j ;

[0042]

[0043] Among them, F θ It is used to adjust the steering range of the seedling conveyor, mainly by changing the frequency difference between the left and right motors to achieve angle correction; K pθ , K iθ , K dθ denote the proportional, integral and differential coefficients respectively;

[0044] The method for adjusting the motor frequency comprises the following steps:

[0045] (5-1) Through F x 、F y and F θ Comprehensive adjustment is performed to ensure the smooth operation of the vehicle. The adjustment formula is:

[0046] f left =f0+(F y -F x )+F θ ;

[0047] f right =f0+(F y +F x )-F θ ;

[0048] Where f0 represents the initial frequency of the motor; F y Indicates the longitudinal deviation correction trend of the seedling conveyor (to avoid the seedling conveyor from deviating forward and backward); F x Indicates the lateral deviation correction trend of the seedling conveyor (to prevent the seedling conveyor from deviating left or right); F θ Indicates adjusting the angle direction of the seedling conveyor, giving priority to ensuring that the seedling conveyor faces the target point;

[0049] (5-2) In order to ensure the safe operation of the motor, the frequency f leftand f right It should be controlled within the allowable range, the specific frequency range is:

[0050] f min ≦f left , f right ≦f max .

[0051] By adopting the above technical solution, combined with the calculation of displacement deviation and angle deviation, the motor frequency is dynamically adjusted using the PID controller to achieve high-precision real-time deviation correction of the seedling conveyor trajectory, ensuring that the seedling conveyor can quickly return to the target trajectory. Dynamically adjust the PID control parameter K p , K i , K d , the present invention can reduce the cumulative deviation when driving at low speed, and enhance the response capability to rapid changes when driving at high speed, so as to adapt to different operating environments and speed requirements. When adjusting the motor frequency, frequency limit and normalization processing are set to prevent the frequency from exceeding the safe operating range of the motor, extend the service life of the motor and reduce maintenance costs. The smoothing of the motor frequency avoids the vibration of the seedling conveyor or motor overload loss caused by frequency mutation, thereby improving the stability of the system and the driving smoothness of the seedling conveyor. Real-time closed-loop control is adopted to achieve rapid response and efficient deviation correction by continuously updating the deviation calculation and adjusting the motor frequency, ensuring that the seedling conveyor is always stable on the target trajectory. Through PID control and frequency adjustment methods, precise control can be achieved without complex hardware or high computing power equipment, which greatly reduces the development and maintenance costs, and has high economy and engineering practicality.

[0052] Furthermore, the adjustment signal described in step 2-4 is generated by a closed-loop control method, wherein the adjustment signal is continuously adjusted according to the deviation value fed back in real time to ensure that the deviation between the actual trajectory and the virtual trajectory is minimized.

[0053] By adopting the above technical solutions, the core feature of the closed-loop control method is real-time feedback and adjustment, which enables the mobile seedling transporter to continuously monitor the deviation between its current position and the target trajectory during operation, and dynamically correct it through the control algorithm. This method can significantly improve the operating accuracy of the equipment and ensure that the machine always travels along the predetermined path. Especially in complex terrain or long-term operation, closed-loop control can prevent the accumulation of errors. In long-term agricultural operations, the closed-loop control method can ensure the stability of the machine's path accuracy and avoid operation failure or inefficiency due to long-term deviation. Closed-loop control enables the mobile seedling transporter to quickly respond to changes in the external environment, such as terrain changes, obstacles, GPS signal fluctuations, etc., by real-time monitoring of the system status and feedback adjustment. Compared with open-loop control, closed-loop control has stronger adaptability and adjustment capabilities in the face of dynamic environments, and can ensure the stable operation of the equipment. The closed-loop control system can immediately adjust the steering or speed when the equipment deviates, so that the equipment can quickly return to the predetermined path. This is crucial for dealing with suddenly changing farmland environments (such as obstacles, potholes, etc.). When the machine faces complex or irregular terrain, closed-loop control can dynamically adjust the control strategy based on feedback signals to optimize the operating path.

[0054] Furthermore, the method is applied to the precise trajectory tracking and deviation correction of agricultural mobile seedling transporters.

[0055] By adopting the above technical solution, the method can flexibly respond to complex terrain through high-precision positioning and real-time correction, avoiding the problems of high cost, low adaptability and low flexibility of fixed tracks. In addition, the application of GPS navigation system can greatly improve operation accuracy, reduce energy and maintenance costs, and improve the efficiency and intelligence level of agricultural production. Therefore, the automatic correction control method based on GPS navigation has broad application prospects and provides a more efficient and economical solution for modern agricultural automation equipment.

[0056] In summary, the present invention includes at least one of the following beneficial technical effects:

[0057] (1) High-precision positioning and real-time deviation correction in the present invention The seedling transporter based on GPS navigation can accurately determine its position in the farmland through real-time GPS coordinate data, and compare it with the predetermined trajectory to calculate the deviation value. Through the PID algorithm, the system can automatically correct the deviation in real time to ensure that the seedling transporter can accurately travel along the predetermined trajectory. The accuracy of the seedling transporter is greatly improved through high-precision positioning and real-time deviation correction capabilities.

[0058] (2) The present invention can dynamically adjust the path according to real-time GPS data to adapt to various complex terrain conditions. Whether on slopes, hills or irregular farmland, the GPS navigation system can provide stable navigation support to ensure that the equipment can operate efficiently and adapt to operations in complex terrain conditions.

[0059] (3) The present invention does not require the laying of fixed tracks, which can reduce the cost and time of early track laying and avoid the additional maintenance costs caused by track damage. Therefore, farmers can use the seedling transporter efficiently in any area, greatly improving the flexibility of agricultural production.

[0060] (4) The present invention can flexibly adjust the path planning according to the needs of different farmlands. The crop planting layout and regional changes in the farmland can be dynamically adjusted through GPS navigation without the need to rebuild the track or carry out large-scale repair work. Therefore, farmers can plan the path according to production needs at any time, thereby improving production efficiency.

[0061] (5) The GPS system of the present invention can effectively optimize route planning and reduce ineffective driving, thereby reducing energy consumption and extending the service life of equipment, greatly reducing energy consumption and equipment maintenance costs.

[0062] (6) The present invention has a high degree of automation and can be combined with other sensors such as gyroscopes and accelerometers to achieve more accurate path tracking and obstacle detection, especially under complex weather conditions. It can reduce human intervention and human operation errors and improve the automation and intelligence level of agricultural production. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a schematic diagram of the overall structure of the seedling transporter of the present invention.

[0064] Figure 2 It is a schematic diagram of the deviation correction process of the seedling conveyor in the present invention.

[0065] Figure 3 It is a schematic diagram of the coordinate system and trajectory of the seedling transporter structure in the present invention.

[0066] Figure 4 It is a block diagram of the control system of the seedling conveyor in the present invention.

[0067] In the figure: steering rear wheel 1, steering rear wheel 2, steering front wheel 1, steering rear wheel 2, 4, seedling tray conveyor belt 5, conveyor belt motor 6, GPS positioning module A7, GPS positioning module B8, control system 9. DETAILED DESCRIPTION

[0068] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art fall within the scope defined by the claims attached to this application.

[0069] Example

[0070] like Figure 1 As shown, the seedling conveyor based on GPS navigation is composed of a frame, a conveyor belt motor 6 arranged on the frame, a seedling tray conveyor belt 5 driven by the conveyor belt motor 6, a steering rear wheel 1 connected to the frame and independently driven, a steering rear wheel 2, a steering front wheel 3, a steering rear wheel 4, a GPS positioning module A 7 connected to the steering front wheel, a GPS positioning module B 8 connected to the steering rear wheel, and a control system 9 connected to the frame and composed of a GPS receiver, a deviation correction and solution terminal, and a steering wheel motor. The GPS positioning module A 7 and the GPS positioning module B 8 are connected to the GPS receiver and feed data back to the deviation correction and solution terminal. The deviation correction and solution terminal is connected to the steering wheel motor control, and the steering wheel motor drives the steering wheel group to finally drive the frame and the seedling tray conveyor belt 5 to change and adjust the position and angle.

[0071] In this embodiment, the mobile seedling transporter is equipped with a GPS positioning module and a PID control system. By acquiring GPS coordinate information in real time, the system can accurately know the current position of the seedling transporter, compare it with the preset trajectory, and make corrections according to the deviation value. The core goal of the system is to ensure that the seedling transporter travels accurately along the planned path.

[0072] Specifically, the main components are selected as follows:

[0073] GPS module: Use a high-precision differential GPS module with an accuracy of ±0.5m, which can provide real-time coordinate data. The update frequency of the GPS module is 1Hz, which can provide a position update once a second.

[0074] Control system: Based on PID control algorithm, combined with GPS coordinates and sensor data for real-time deviation adjustment. The operating frequency of the control system is 50Hz.

[0075] Drive motor: Use DC servo motor with maximum speed of 3000RPM and maximum output torque of 10Nm.

[0076] By combining GPS positioning calculations, the system can obtain the current position of the seedling transporter more accurately and perform real-time corrections based on the preset trajectory.

[0077] like Figure 2-3As shown, the automatic deviation correction control method of the seedling transporter in this embodiment includes: position deviation calculation, angle deviation calculation, position deviation adjustment, angle deviation adjustment, and motor frequency adjustment.

[0078] The specific process is as follows:

[0079] (1) Obtaining GPS positioning data

[0080] The GPS module provides coordinate information in real time. For example, assuming that the current GPS A and B coordinates of the seedling conveyor are (8, 80) and (10, 100) respectively, the calculation formula is: Actual trajectory point Q j =(9,90). The system will compare the current GPS coordinates with the target point (10,100) in the preset track and calculate the deviation distance Δx j =1 and Δy j = 10, calculate the slope m of the adjacent virtual track points (10, 100) and (10, 101) on the virtual track virtual , Adjacent actual track point Q j (9,90) and Q j+1 = slope m of (8, 95) actual ,

[0081] Calculate the angle deviation Δθ between the actual track slope and the virtual track slope j , the calculation formula is:

[0082] Δθ j =arctan(m actual )-arctan(m virtual )=78°According to the formula Δx adjust =k displacement ·Δx j ,

[0083] Δy adjust =k displacement ·Δy j ,θ adjust =k angle ·Δθ j Calculated Δx adjust is 25cm, Δy adjust is 35cm, θ adjust If it is 15°, it means that the seedling conveyor has deviated.

[0084] (2) PID control system

[0085] The control system combines GPS coordinates and deviation information to calculate the correction signal. According to the formula

[0086]

[0087] Assume that the correction signal F output by the PID algorithm is x 5N·m, F y 50N·m, F θ This signal will drive the motor to adjust and ensure that the seedling conveyor can be corrected to the target trajectory.

[0088] (3) Adjust the motor output

[0089] Based on the correction signal output by the PID algorithm, the servo motor adjusts the speed of the left and right wheels to correct the direction and position of the seedling transporter.

[0090] According to f left =f0+(F y -F x )+F θ ;

[0091] f right =f0+(F y +F x )-F θ ;

[0092] Assuming f0 = 2000RPM, the left motor speed increases to 2200RPM, and the right motor decreases to 1800RPM. The deviation correction motor corrects the steering angle of the wheel by 15° to ensure that the seedling conveyor gradually approaches the target track.

[0093] (4) Adaptive Adjustment

[0094] As the seedling conveyor moves, the system will continue to obtain GPS coordinates and deviation data. After each deviation correction, the GPS module provides new coordinate information, the control system recalculates the deviation, and continues to adjust the motor output until the seedling conveyor moves stably along the predetermined track.

Claims

1. A seedling conveyor based on GPS navigation, comprising a frame, a conveyor motor (6) arranged on the frame, and a seedling tray conveyor belt (5) connected and driven by the conveyor motor (6); characterized in that: The seedling conveyor also includes: A steering wheel group is connected to the frame and consists of a steering front wheel and a steering rear wheel. The steering wheel group drives the frame and the seedling tray conveyor belt (5) to change the position and angle direction; A GPS positioning module A (7), connected to the steering front wheel; A GPS positioning module B (8), connected to the steering rear wheel; A control system (9) is connected and fixed to the frame and is composed of a GPS receiver, a deviation correction and solution terminal, and a steering wheel motor; The GPS positioning module A (7) and the GPS positioning module B (8) are connected to the GPS receiver and feed data back to the deviation correction and solution terminal. The deviation correction and solution terminal is connected to the steering wheel motor control, and the steering wheel motor drives the steering wheel group to change and adjust the position and angle.

2. The seedling transporter based on GPS navigation according to claim 1, characterized in that: The steering wheels in the steering wheel set are all independently driven steering wheels.

3. The automatic deviation correction control method of the seedling conveyor is characterized in that: The automatic deviation correction control method comprises: Position deviation calculation, angle deviation calculation, position deviation adjustment, angle deviation adjustment, motor frequency adjustment; The method for calculating the position deviation comprises the following steps: (1-1) Coordinate system establishment: An xy axis coordinate system is established on the travel path of the seedling transporter, wherein the y axis is parallel to the travel direction of the seedling transporter, the x axis is perpendicular to the travel direction of the seedling transporter, and a certain position on the x axis is set as the starting position or reference point; in this coordinate system, the coordinate point (x a ,y a ), obtain the coordinate point (x b ,y b ); The midpoint of the mobile seedling conveyor is taken as the position of the trajectory point, marked as Q j , Q j =(x j ,y j ), Q j The calculation formula is: Q j is the actual trajectory point; (1-2) Using the virtual track data of the mobile seedling transporter, we can obtain the virtual track point set P virtual = {P1, P2, ..., P n }, each virtual orbit point P k The coordinates of (x k ,y k ); (1-3) Use the deviation correction and solution terminal to obtain each actual track point Q of the mobile seedling transporter j The coordinates of (x j ,y j ); (1-4) For each actual trajectory point Q j , calculate its difference with the virtual orbit point set P virtual The Euclidean distance d of each point in jk , select the virtual track point P with the smallest distance nearest , calculate the deviation Δx between the actual trajectory point and the selected virtual trajectory point j and Δy j ; (1-5) According to the deviation Δx j and Δy j , calculate the position deviation The method for calculating the angle deviation comprises the following steps: (2-1) Calculate the adjacent virtual track points P on the virtual track k and P k+1 The slope m virtual , (2-2) Calculate the adjacent actual track points Q on the actual track j and Q j+1 The slope m actual , (2-3) Calculate the angle deviation Δθ between the actual track slope and the virtual track slope j , the calculation formula is: Δθ j =arctan(m actual )-arctan(m virtual ); (2-4) According to the calculated deviation Δd j and Δθ j , generating an adjustment signal to the deviation correction and solution terminal, driving the rotating wheel motor through the control system, and the steering wheel motor drives the steering wheel to adjust the driving position or (and) angle of the seedling transporter so that the actual track is as close to the virtual track as possible; The method for position deviation adjustment comprises the following steps: (3-1) The displacement deviation is corrected by adjusting the movement of the seedling transporter wheel legs along the x-axis (and) or y-axis direction. The adjustment formula is: Δx adjust =k displacement ·Δx j ; Δy adjust =k displacement ·Δy j ; Among them, k displacement is the displacement adjustment factor; (3-2) For displacement deviation Δx adjust , Δy adjust Design PID controllers separately: Among them, F x Indicates the lateral deviation correction trend of the seedling conveyor; F y Indicates the longitudinal deviation correction trend of the seedling conveyor; K p , K i , K d They represent the proportional, integral and differential coefficients of the position deviation in the PID controller respectively; The method for adjusting the angle deviation comprises the following steps: (4-1) By calculating the difference between the actual track slope and the virtual track slope, the angle adjustment amount θ is generated. adjust , the angle adjustment calculation formula is: i adjust =k angle ·Dth j ; Among them, k angle is the angle adjustment factor; (4-2) Through the angle deviation Δθ j , adjust the steering range F of the seedling conveyor θ , F θ The calculation formula is as follows: where F θ It is used to adjust the steering range of the seedling conveyor, mainly by changing the frequency difference between the left and right motors to achieve angle correction; K pθ , K iθ , K dθ They represent the proportional, integral and differential coefficients of the angle deviation in the PID controller respectively; The method for adjusting the motor frequency comprises the following steps: (5-1) Through F x 、F y and F θ Comprehensive adjustment is performed to ensure the smooth operation of the vehicle. The adjustment formula is: f left =f0+(F y -F x )+F θ ; f right =f0+(F y +F x )-F θ ; Among them, f0 represents the initial frequency of the motor; (5-2) In order to ensure the safe operation of the motor, the frequency f left and f right It should be controlled within the allowable range, the specific frequency range is: f min ≦f left ,f right ≦f max 。 4. The method for calculating and adjusting the trajectory deviation of a seedling conveyor according to claim 3 is characterized in that: The adjustment signal described in step 2-4 is generated by a closed-loop control method, wherein the adjustment signal is continuously adjusted according to the deviation value fed back in real time to ensure that the deviation between the actual trajectory and the virtual trajectory is minimized.

5. The method for calculating and adjusting the trajectory deviation of a seedling conveyor according to claim 3, characterized in that: The method is applied to the precise trajectory tracking and deviation correction of an agricultural mobile seedling transporter.

Images