Self-adaptive control method and device for harvester reel

Abstract

The present application relates to the technical field of agricultural machinery intelligence, and more particularly to a self-adaptive control method and device for a harvester reel. The control method comprises the following steps: establishing a reel speed control parameter table in different density intervals according to crop density intervals; detecting the number of crops per unit area to calculate the crop density; detecting the crop impact force to calculate the average force and obtain the change amount of the average force in two cycles; adjusting the reel speed according to the control parameter table, the crop density and the change amount of the average force; detecting the crop height and obtaining the crop lodging state by taking the average value, and adjusting the position of the reel according to the crop height and the lodging state. By real-time monitoring of the crop density, moisture content and state information of the reel, the reel speed and position are accurately controlled to adapt to the harvesting needs of different crops and reduce the work intensity of the operator.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of intelligent agricultural machinery, and in particular to a self-adaptive control method and device for a harvester reel. BACKGROUND

[0002] In agricultural production, a harvester is an indispensable important equipment, which can efficiently complete the harvesting of crops. The reel is a key component of the header of the harvester, and its main function is to push the crops to the cutter to facilitate harvesting.

[0003] The rotation speed and position of the reel have a crucial influence on the harvesting effect. If the rotation speed of the reel is too fast, it will cause a greater impact on the plants, resulting in grain falling and loss; and if the rotation speed is too slow, it will not be able to timely pull the straw to the cutter, increasing the cutting difficulty, and also causing the grain to fall. In addition, if the position of the reel is too high, it will hit the ear, causing the grain to fall; and if the position is too low, it will cause the cut grain to be thrown out of the header, resulting in loss.

[0004] In actual application, the plant height of different crops is quite different, and even for the same crop, the plant height will also be different due to different growth conditions. Therefore, in order to obtain an ideal harvesting effect, it is necessary to adjust the up-down and front-back positions of the reel according to the actual situation; at the same time, the reel feeding amount will change with the change of the working speed of the harvester and the crop density, and the rotation speed of the reel also needs to be adjusted accordingly.

[0005] Although the rotation speed of the reel is matched with the forward speed in the prior art, the influence of different crops, crop density and crop moisture content on the reel speed ratio is not fully considered, resulting in inaccurate adjustment and being unable to fundamentally solve the problem of large loss. SUMMARY

[0006] In view of the deficiencies in the prior art, the purpose of the embodiments of the present application is to provide a self-adaptive control method for a harvester reel, which can accurately control the rotation speed and position of the reel by monitoring the crop density, moisture content and state information of the reel in real time, so as to adapt to the harvesting requirements of different crops, reduce the working intensity of the operator, and improve the quality and efficiency of harvesting.

[0007] In order to achieve the above purpose, the embodiments of the present application provide the following technical solutions:

[0008] The application discloses a self-adaptive regulation method for a harvesting machine reel, and comprises the following steps: setting a crop density interval, establishing a reel rotating speed control parameter table in different density intervals, detecting the number of crops in a unit area, calculating the crop density, detecting the crop impact force, calculating the average force, obtaining the variation of the average force in two periods, adjusting the rotating speed of the reel according to the control parameter table, the crop density and the variation of the average force, detecting the crop height and obtaining the crop lodging state by taking the average value, and adjusting the position of the reel according to the crop height and the lodging state.

[0009] The regulation method realizes accurate adjustment of the rotating speed of the reel by establishing the reel rotating speed control parameter table in different density intervals, combining the detected crop density and the variation of the average force, and further adjusting the position of the reel by detecting the crop height and judging the lodging state. The method can dynamically adjust the working state of the reel according to the actual crop situation, improve the harvesting efficiency and quality, and reduce the crop loss.

[0010] Further, when establishing the parameter table, the median value in the interval is taken as the reference density, the data set of the machine tool advancing speed, the PID control parameter, the reel rotating speed measurement value and the reel rotating speed ratio is collected, the BP neural network is established, and the BP neural network model is optimized by using the genetic algorithm to establish the optimal control parameter table of the reel rotating speed regulation in different density intervals.

[0011] By taking the median value in the interval as the reference density, collecting the relevant data set, using the BP neural network and combining the genetic algorithm optimization, the optimal control parameter table is established. This process uses advanced algorithms and data processing technology to improve the accuracy and adaptability of the parameter table, so that the rotating speed regulation of the reel is more scientific and reasonable, and can better meet the operation requirements under different crop densities.

[0012] Further, the number of crops in a unit area is obtained by using an image processing method, which comprises the following steps: after image acquisition, the captured image is preprocessed by enhancing the image contrast, the image is gridded and the color features and texture features of crops are extracted, the extracted feature data is standardized, a classification learning method is used to classify the image patches in the image, and then the crop contour is recognized, the crop contour image is thinned by hole filling, the total number of crops in the image is calculated, and the number of grains in a unit area is obtained.

[0013] Through a series of operations such as image acquisition, preprocessing, feature extraction, classification learning and contour recognition, the number of crops in a unit area, i.e. the crop density, is accurately calculated. This method uses the advantages of image processing technology to quickly and accurately obtain the crop density information, and provides reliable data support for subsequent reel rotating speed adjustment.

[0014] Further, the variation of the average force in two periods The calculation process includes:

[0015] According to the formula F = m(v-v0) / t, where F is the instantaneous impact force, m is the mass of the crop including dry weight and moisture content, v is the speed of the crop after impact, v0 is the speed of the crop before impact, and t is the impact time. The average force in one cycle of N rotations of the reel is

[0016] The instantaneous impact force is calculated by a specific formula, and the average force in one cycle is calculated by taking N rotations of the reel as one cycle. This method can accurately reflect the force on the crop during the reel process, and thus the change in the average force can provide a basis for adjusting the reel speed, ensuring the optimal working state of the reel under different crop moisture conditions.

[0017] Further, the reel speed self-adaptive control process includes: when the crop density changes and the density value exceeds the density interval, the optimal control parameter value corresponding to the reference density in the interval where the changed density value is located in the control parameter table is called to adjust the reel speed; when the crop density changes and the density value does not exceed the density interval, if the change amount of the average force exceeds the first threshold range, the reel speed is adjusted; when the change amount of the average force exceeds the second threshold range, the reel speed is adjusted and the machine forward speed is also adjusted.

[0018] When the crop density changes, the corresponding optimal control parameter value is called to adjust the reel speed according to the interval where the changed density value is located. In addition, the change amount of the average force is also considered, and when it exceeds the set threshold range, the reel speed and machine forward speed are further adjusted. This hierarchical control method can more finely adjust the working state of the reel, adapt to changes in different crop densities and moisture contents, and improve the adaptability and efficiency of harvesting operations.

[0019] Further, when the change amount of the average force is greater than the first threshold range, the reel speed is reduced; when the change amount of the average force is less than the first threshold range, the reel speed is increased; when the change amount of the average force is greater than the second threshold range, the reel speed is reduced and the machine forward speed is also reduced; when the change amount of the average force is less than the second threshold range, the reel speed is increased and the machine forward speed is also increased. This specific adjustment strategy can ensure that the reel maintains the best working effect under different working conditions, reduces crop loss, and improves harvesting quality.

[0020] The embodiment of the present application also provides a regulating device for the self-adaptive regulation method of the harvester reel, comprising: an information acquisition device, configured to acquire crop density, crop impact force and crop height information; a controller, configured to adjust the rotating speed and position of the reel according to the acquired information; and an executing mechanism, configured to execute the instructions from the controller to adjust the rotating speed and position of the reel. The device has a simple and clear structure design, and the parts work cooperatively to efficiently realize the self-adaptive regulation of the reel and improve the intelligent level and operation performance of the harvester.

[0021] Further, the information acquisition device comprises an industrial camera, a traveling speed sensor, a reel rotating speed sensor, a reel position detection device, a crop quality detection device and a crop height detection device; the industrial camera is installed at the top of the front end of the harvester; the traveling speed sensor is installed on the traveling system of the harvester; the reel rotating speed sensor is installed on the reel support at the end of the reel rotating shaft; the reel position detection device comprises a reel height detection device and a reel front and rear position detection device, one end of the reel height detection device is installed on the header body, and the other end is connected with the reel support; one end of the reel front and rear position detection device is installed on the reel support, and the other end is connected with the end of the reel rotating shaft; and the crop height detection device is installed on one side of the front part of the header body.

[0022] The sensors are installed at the corresponding positions of the harvester to ensure that the required information can be accurately acquired. The detailed installation layout design enables the information acquisition device to comprehensively and accurately acquire various data in the operation process, thereby providing sufficient basis for the decision of the controller.

[0023] Further, the crop quality detection device is installed on the spring tooth shaft of the reel and is distributed in a staggered manner, comprising a force receiving plate, a force receiving arm, a strain gauge and a protective cover, the force receiving plate and the force receiving arm are connected with the spring tooth shaft through a hoop, the strain gauge and the protective cover are installed on the force receiving arm, and a signal line is connected with a control terminal through a slip ring installed at the reel rotating shaft.

[0024] The structure design can accurately measure the impact force of the crops in the process of being raked, and then calculate the average force, thereby providing key data for the adjustment of the rotating speed of the reel. Through the fine structure design, the accuracy and reliability of the crop quality detection are improved, and the self-adaptive regulation effect of the reel is further optimized.

[0025] Further, the executing mechanism comprises a reel, a reel lifting hydraulic cylinder, a reel front and rear action hydraulic cylinder and a proportional valve group; the fixed end of the reel front and rear action hydraulic cylinder is fixed on the reel support, and the telescopic end is installed on the end of the reel rotating shaft; the fixed end of the reel lifting action hydraulic cylinder is fixed on the header body, and the telescopic end is installed on the reel support.

[0026] The forward and backward and up and down position adjustment of the reel is realized through the extension and retraction action of the hydraulic cylinder. The design of the actuator can quickly and accurately respond to the instructions of the controller, realize the accurate adjustment of the reel position, and ensure the optimal working state of the harvester under different working conditions.

[0027] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0028] The present application measures the change of crop moisture content by impact force detection method, adjusts the parameters of the control unit according to the change of crop density and crop moisture content, outputs the corresponding PWM value to control the reel speed, and adjusts the up and down and front and rear positions of the reel according to the change of crop height in real time, so as to realize the adaptive control of the reel under different crop conditions, reduce the working intensity of the operator, and improve the quality and efficiency of harvesting.

[0029] When the crop density changes, the corresponding optimal control parameter value is called according to the interval of the changed density value to adjust the speed of the reel. In addition, the change amount of the average stress is also considered, and when it exceeds the set threshold range, the speed of the reel and the forward speed of the machine are further adjusted. This hierarchical control method can more finely adjust the working state of the reel, adapt to the change of different crop density and moisture content, and improve the adaptability and efficiency of the harvesting operation.

[0030] The advantages of the additional aspects of the present application will be given in the following description, some of which will become apparent from the following description, or will be understood through practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor. In addition, the mutual distance or size is exaggerated to show the position of each component, and the schematic diagram is only used for illustration.

[0032] Figure 1 is a schematic diagram of the installation of the regulating device provided by the embodiments of the present application;

[0033] Figure 2 is a schematic diagram of the crop quality detection device provided by the embodiments of the present application;

[0034] Figure 3 is a schematic diagram of the installation position of the crop quality detection device provided by the embodiments of the present application;

[0035] In the figure: 1, header body; 2, reel height detection device; 3, reel lifting hydraulic cylinder; 4, crop quality detection device; 5, reel; 6, crop height detection device; 7, reel rotation speed sensor; 8, reel front and rear action hydraulic cylinder; 9, reel front and rear position detection device; 10, industrial camera; 11, force arm; 12, sleeve; 13, signal line; 14, protective cover; 15, strain gauge; 16, force plate. DETAILED DESCRIPTION

[0036] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Furthermore, it should be understood that the terms "comprise" and / or "comprising", when used in this specification, designate the presence of stated features, steps, operations, devices, components and / or combinations thereof.

[0037] Terminology:

[0038] Reel speed ratio: refers to the ratio of the linear speed of the reel to the forward speed of the harvester.

[0039] Example 1

[0040] In order to realize the optimal control of the reel rotation speed, position, crop density, crop moisture content and crop height, improve work efficiency and reduce harvesting loss, the present embodiment proposes a reel self-adaptive control device for a harvester, which comprises an information acquisition device, a controller and an execution mechanism.

[0041] As shown in Figure 1 , Figure 2 , the information acquisition device comprises an industrial camera 10, a forward speed sensor, a reel rotation speed sensor 7, a reel position detection device, a crop quality detection device 4 and a crop height detection device 6.

[0042] As shown in Figure 1 , the industrial camera 10 is installed at the top of the front end of the harvester; the forward speed sensor is installed on the walking system of the harvester; the reel rotation speed sensor 7 is installed on the reel support at the end of the reel rotation shaft; the reel position detection device comprises a reel height detection device 2 and a reel front and rear position detection device 9, one end of the reel height detection device 2 is installed on the header body 1 and the other end is connected with the reel support; one end of the reel front and rear position detection device 9 is installed on the reel support and the other end is connected with the end of the reel rotation shaft. The crop height detection device 6 is installed on one side of the front end of the header body 1.

[0043] As shown in Figure 2As shown, the crop quality detection device 4 is installed on the tine shaft of the reel and is distributed, including the force plate 16, the force arm 11, the strain gauge 15, the protective cover 14, the sleeve 12, the signal line 13 and the like. The force plate 16 and the force arm 11 are connected with the tine shaft through the sleeve 12, the strain gauge 15 and the protective cover 14 are installed on the force arm 11, and the signal line 13 is connected with the control terminal through the slip ring installed at the rotating shaft of the reel. Five crop quality detection devices are installed on the tine shaft of the reel, as shown in the figure. Figure 3 The installation sequence of the crop quality detection devices on the five tine shafts of the reel is 13-24-25-14-35 in turn.

[0044] The actuator includes the reel 5, the reel lifting hydraulic cylinder 3, the reel forward and backward movement hydraulic cylinder 8 and the proportional valve group. One end of the reel forward and backward movement hydraulic cylinder 8 is fixed on the reel support, and the telescopic end is installed on the end of the reel rotating shaft. One end of the reel lifting hydraulic cylinder 3 is fixed on the header body, and the telescopic end is installed on the reel support.

[0045] The self-adaptive control method of the harvester reel mainly includes self-adaptive control of the reel rotating speed and self-adaptive control of the reel position.

[0046] (1) Self-adaptive control of the reel rotating speed

[0047] The crop density interval is set, the median value in the interval is taken as the reference density, a data set of the implement forward speed, the PID control parameter, the reel rotating speed detection value and the reel speed ratio at a certain reference density is selected to establish the BP neural network, the genetic algorithm is used to optimize the BP neural network model, and the optimal control parameter table of the reel rotating speed control in different density intervals is established.

[0048] The crop density detection adopts the image processing method to obtain the number of spikes in a unit area. In order to prevent the overlap or omission of the shooting area of the industrial camera 10, the condition must be met Wherein T is the interval time of camera shooting, D is the length of the camera field of view range, and v is the implement forward speed. After image acquisition, the contrast of the enhanced image is preprocessed, the image is gridded, the color features and texture features of the spikes are extracted, the extracted feature data is standardized, the image spots are classified by using the classification learning method, and then the spike contour is identified. The spike contour image is thinned through hole filling, the total number of spikes in the image is calculated, and the number of spikes in a unit area is obtained.

[0049] The crop quality detection device 4 is used to detect the impact force of the crop, and the change of the impact force is used to detect the change of the water content of the crop. According to the formula F=m(v-v0) / t, wherein: F is the instantaneous impact force; m is the mass of the crop, including the dry weight and the water content; v is the speed of the crop after impact; v0 is the speed of the crop before impact; and t is the impact time. Before the crop is impacted during the harvesting operation, v0=0, and after the crop is impacted, the crop moves a distance with the reel, and v can be regarded as being equal to the linear speed v b of the reel. Therefore, the impact force is proportional to the mass of the crop, and F=km, wherein k=v / t. One cycle is N rotations of the reel, and the average force of the crop quality detection device on the spring tine shaft in one cycle is wherein i is the number of detection devices, which are installed in five installation areas; j is the number of rotations; the change of the water content of the crop will cause the change of the average force, and the change of the average force in two cycles is The change of the average force in two cycles is used as the judgment condition for the speed regulation of the reel.

[0050] The self-adaptive speed regulation process of the reel is divided into three cases:

[0051] ① When the crop density ρ changes and the density value exceeds the density interval, the controller calls the optimal control parameter value corresponding to the reference density of the interval in which the changed density value ρ' is located in the control parameter table, outputs the PWM signal to control the opening of the electromagnetic proportional valve, adjusts the speed of the reel, and realizes the self-adaptive adjustment of the speed of the reel and the crop density.

[0052] ② When the crop density ρ changes and the density value does not exceed the density interval, if the first threshold range in the density interval is not met , the controller adjusts the opening of the electromagnetic proportional valve to reduce the speed of the reel; , the controller adjusts the opening of the electromagnetic proportional valve to increase the speed of the reel. During the adjustment process, the speed of the reel is always within the speed regulation threshold range of the density interval, and the self-adaptive adjustment of the speed of the reel and the water content of the crop under the same density condition is realized.

[0053] ③ When the change of the water content is large, the second threshold range is exceeded , if , the speed of the reel is reduced, and the forward speed of the implement is also reduced; , the speed of the reel is increased, and the forward speed of the implement is also increased. During the regulation process, the reel speed ratio λ always meets the threshold range [λ min , λ max ].

[0054] (2) Self-adaptive regulation of the position of the reel

[0055] When the crop in the work plot is in the upright state, the crop height detection device 6 detects the crop height l multiple times and takes the average value, and the average value L obtained is used as the reference value. When l < 0.5L, it is determined that the crop is in the lodging state, and the lifting hydraulic cylinder 3 of the reel is adjusted to the lowest position. According to the image analysis of the crop, the lodging state of the crop is analyzed. When the crop is in the forward lodging state (lodging forward along the direction of the machine), the front and rear action hydraulic cylinder 8 of the reel is adjusted to the limit state, so that the reel is in the most forward working position. When the crop is in the reverse lodging state (lodging backward along the direction of the machine), the front and rear action hydraulic cylinder 8 of the reel is adjusted to the limit state, so that the reel is in the most rear working position. After the reel position is adjusted, the harvester is harvested at low speed, and the reel speed ratio λ is ensured to be greater than 1 and less than λ max .

[0056] The above describes the specific embodiments of the present application in combination with the drawings, but is not a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications or changes made on the basis of the technical solutions of the present application without creative labor are still within the protection scope of the present application.

Claims

1. An adaptive control method for the reel of a harvester, characterized in that, Includes the following steps: Based on crop density ranges, establish a table of control parameters for reel speed in different density ranges; The number of crops per unit area is detected, and the crop density is calculated. Detect the impact force on the crop, calculate the average force, and obtain the change in the average force over two cycles; Adjust the rotational speed of the reel based on the control parameter table, crop density, and changes in average force; specifically: When crop density changes and the density value exceeds the density range, the optimal control parameter value corresponding to the baseline density of the range where the changed density value is located is called from the control parameter table to adjust the speed of the reel. When crop density changes, but the density value does not exceed the density range, if the change in the average force is greater than the maximum value of the first threshold range, decrease the rotation speed of the reel; if the change in the average force is less than the minimum value of the first threshold range, increase the rotation speed of the reel; if the change in the average force is greater than the maximum value of the second threshold range, decrease the rotation speed of the reel and simultaneously reduce the forward speed of the implement; if the change in the average force is less than the minimum value of the second threshold range, increase the rotation speed of the reel and simultaneously increase the forward speed of the implement. The crop height is measured and the average value is taken to obtain the lodging status. The position of the reel is adjusted according to the crop height and lodging status.

2. The adaptive control method for the reel of a harvester as described in claim 1, characterized in that, When establishing the control parameter table, the median value of the interval is used as the reference density. Data sets of machine forward speed, PID control parameters, reel speed measurement, and reel speed ratio are collected. A BP neural network is established, and a genetic algorithm is used to optimize the BP neural network model to establish the optimal control parameter table for reel speed regulation in different density intervals.

3. The adaptive control method for the reel of a harvester as described in claim 1, characterized in that, The number of crops per unit area is obtained by image processing methods, including: preprocessing the captured image by enhancing the image contrast after image acquisition, meshing the image and extracting crop color and texture features, standardizing the extracted feature data, classifying the patches in the image by classification learning methods, and then identifying the crop outline, refining the crop outline image by filling holes, calculating the total number of crops in the image, and obtaining the number of ears of grain per unit area.

4. The adaptive control method for the reel of a harvester as described in claim 1, characterized in that, Change in the average force over two cycles The calculation process includes: The impact force on crops is detected using a crop quality testing device. The calculation formula is F = m(v - v0) / t, where: F is the instantaneous impact force; m is the mass of the crop, including dry weight and moisture content; v is the velocity of the crop after impact; v0 is the velocity of the crop before impact; t is the impact time; and N revolutions of the reel constitute one cycle. The average force within one cycle is... Where i represents the number of crop quality testing devices, which are installed in 5 installation areas; j represents the number of rotations.

5. A control device for the adaptive control method of the harvester reel as described in any one of claims 1-4, characterized in that, include: Information acquisition device used to collect information on crop density, crop impact force, and crop height; The controller is used to adjust the speed and position of the reel based on the collected information; The actuator is used to execute the commands issued by the controller to adjust the speed and position of the reel.

6. The control device as described in claim 5, characterized in that, The information acquisition device includes an industrial camera, a travel speed sensor, a reel rotation speed sensor, a reel position detection device, a crop quality detection device, and a crop height detection device; The industrial camera is mounted on the top front end of the harvester; the travel speed sensor is mounted on the harvester's walking system; the reed rotation speed sensor is mounted on the reed bracket at the end of the reed rotating shaft; the reed position detection device includes a reed height detection device and a reed front-rear position detection device, one end of the reed height detection device is mounted on the header body, and the other end is connected to the reed bracket; one end of the reed front-rear position detection device is mounted on the reed bracket, and the other end is connected to the end of the reed rotating shaft; the crop height detection device is mounted on one side of the front of the header body.

7. The control device as described in claim 6, characterized in that, The crop quality detection device is installed on the spring tooth shaft of the reel and is staggered. It includes a force plate, a force arm, a strain gauge and a protective cover. The force plate and the force arm are connected to the spring tooth shaft through a hoop. The strain gauge and the protective cover are installed on the force arm. The signal line is connected to the control terminal through a slip ring installed at the rotating shaft of the reel.

8. The control device as described in claim 5, characterized in that, The actuator includes a reel, a reel lifting hydraulic cylinder, a reel front and rear movement hydraulic cylinder, and a proportional valve group; the fixed end of the reel front and rear movement hydraulic cylinder is fixed on the reel bracket, and the telescopic end is installed on the reel rotating shaft end; the fixed end of the reel lifting hydraulic cylinder is fixed on the cutter head body, and the telescopic end is installed on the reel bracket.

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