Multi-parameter regulation and control test bed and test method for potato combined harvesting, separation and loss reduction

Abstract

The invention relates to a multi-parameter regulation and control test bed and test method for tuber combine harvesting, separation and loss reduction, and belongs to the technical field of tuber screening test equipment.The test bed comprises a rack, a conveying belt assembly and a test assembly, and the conveying belt assembly comprises a conveying belt, a plurality of rotating shafts, a first driving motor, a vibrating wheel assembly and a second driving motor; the rotating shafts are rotationally installed on the rack, the rotating shafts are sleeved with the conveying belt, and the power end of the first driving motor is connected with one rotating shaft. The vibrating wheel assembly is provided with a vibrating wheel which is eccentrically and rotationally installed on the bottom side of the conveying belt, the second driving motor is installed on the rack, and the power end of the second driving motor is connected with the vibrating wheel to drive the conveying belt to vibrate. The test assembly comprises a controller and an induction piece; the induction piece is installed on the first driving motor and the conveying belt and inducts torque and the rotating speed of the conveying belt, and the induction piece, the first driving motor and the second driving motor are electrically connected with the controller. The test bed disclosed by the invention is timely in regulation and control response, good in potato-soil separation effect and low in potato block damage.

Description

Technical Field

[0001] This invention belongs to the technical field of potato screening test equipment, specifically relating to a multi-parameter control test bench and test method for potato combined harvesting, separation and loss reduction. Background Technology

[0002] A potato screening machine is a vibrating screening device used for tuber crops such as potatoes and starch plants. Its main functions include material grading and impurity removal. Most models employ linear vibrating screen technology, causing the screen body to vibrate along a straight trajectory. By screening, tuber crops are separated into different grades according to size, and impurities such as mud and stones are removed, ensuring the quality of subsequent processing. Potato screening test equipment is used during the research and development and production of potato screening machines, primarily for collecting experimental data on equipment structure and automatic control systems.

[0003] Traditional potato screening testing equipment uses a potato screening machine as the testing machine, adding testing equipment to simulate the actual potato screening process. However, existing potato screening testing equipment has the following drawbacks: High dependence on manual adjustment: The control system of the existing potato screening test equipment is a fixed control mode. During the test, the amount of potato fed is a dynamic input, and the control system relies on manual adjustment. This can easily lead to a decrease in separation efficiency or damage to the potato tubers due to adjustment lag.

[0004] Poor potato-soil separation effect: The vibration amplitude adjustment of existing potato screening test equipment requires manual operation and cannot be automatically adapted to the real-time potato-soil separation status. In addition, for different potato-soil mixing requirements, the existing test equipment requires multiple manual stops to adjust the amplitude, resulting in low potato-soil separation efficiency.

[0005] 2. The safety protection mechanism is too simple: feeding will only stop or speed will be reduced when potato chunks accumulate on the conveyor belt and the output power of the drive unit reaches the shutdown threshold. Emergency handling for sudden failures (such as inverter failure or sensor failure) is not considered, which may result in sudden equipment stoppage or continuous abnormal operation.

[0006] 3. Limitations of flexible buffer design: In the potato collection area, although buffer components are used to collect potato tubers, the conveyor belt body only relies on external flexible rubber to reduce damage. When the potato tubers are large or the conveyor belt speed is high, the collision between the potato tubers and the conveyor belt body or between the potato tubers may still cause skin damage. There is room for improvement in the buffer protection effect.

[0007] 4. Insufficient correlation of control parameters: The existing potato screening test equipment is a fixed control method, which does not take into account the influence of variables such as soil moisture and tuber size on parameter matching, thus limiting its versatility.

[0008] 5. Difficulty in Observing the Experimental Process: Existing experimental equipment often uses baffles on both sides of the conveyor belt, making it impossible to directly observe the screening status of the potato tubers on the conveyor belt. This prevents experimenters from adjusting parameters in a timely manner based on the screening results, leading to low testing efficiency, delayed data collection, and low data accuracy. Therefore, a multi-parameter control experimental platform for potato combined harvesting, separation, and loss reduction is needed to address the problems of existing potato screening equipment, such as delayed control during dynamic potato feeding, reduced screening efficiency, easy damage to potato tubers during screening, and low versatility. Summary of the Invention

[0009] The purpose of this invention is to provide a multi-parameter control test bench and test method for potato combined harvesting and loss reduction, so as to solve the problems mentioned in the background art.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a multi-parameter control test bench for potato combined harvesting and loss reduction, comprising a frame, a conveyor belt assembly, and a test assembly. The conveyor belt assembly includes a conveyor belt, several rotating shafts, a first drive motor, a vibrating wheel assembly, and a second drive motor. The several rotating shafts are rotatably mounted on the frame, and the conveyor belt is sleeved on the outside of the rotating shafts. The power end of the first drive motor is connected to one of the rotating shafts to form a conveying channel. The vibrating wheel assembly has a vibrating wheel, which is eccentrically mounted on the bottom side of the conveyor belt. The second drive motor is mounted on the frame, and its power end is connected to the vibrating wheel to drive the conveyor belt to reciprocate radially. The test assembly includes a controller, a sensor, and a frequency converter. The sensor is mounted on the first drive motor and the conveyor belt to sense the torque of the first drive motor and the rotational speed of the conveyor belt. The frequency converter is electrically connected to the first drive motor and the second drive motor, respectively. The sensor, the first drive motor, the second drive motor, and the frequency converter are electrically connected to the controller.

[0011] Preferably, the frame includes a conveyor belt, a base, and a housing; the housing is mounted on the upper side of the base and includes two side plates, which are mounted parallel to each other on the base, and several rotating shafts are rotatably mounted between the two side plates at intervals; the conveyor belt is mounted on the inlet side of the conveying channel, and a potato collecting plate is mounted on the outlet side of the conveying channel; one side of the rotating shaft connected to the first drive motor extends to the outside of the side plate to form a mounting end, and a drive wheel is mounted on the mounting end; the first drive motor is connected to the drive wheel via a drive belt, and driven drive wheels are mounted on the remaining rotating shafts, and a synchronous belt connects the driven drive wheels.

[0012] Preferably, a secondary support wheel is rotatably mounted on the frame, and the conveyor belt is sleeved on the outside of the secondary support wheel, dividing the conveyor belt into two conveying and screening sections with the secondary support wheel as the boundary. A vibrating wheel assembly is installed on the frame at the location of each conveying and screening section. The conveying and screening section located on the inlet side of the potato conveying channel is defined as the first screening section, and the conveying and screening section located on the outlet side of the potato conveying channel is defined as the second screening section. A chute is opened on the frame of the second screening section located on the outlet side of the potato conveying channel, and the rotating shaft at the end of the second screening section is slidably mounted on the chute to form an adjustable conveyor belt length structure.

[0013] Preferably, the box body on one side of the conveyor belt is hinged to the base, and the box body on the side away from the conveyor belt is rotatably mounted on the base with an adjusting ball screw, and a stop plate is installed at the top of the adjusting ball screw; the side plate is made of transparent material; the conveyor belt is equipped with a conveying motor, and the conveyor belt is equipped with a speed controller, which is electrically connected to the conveying motor and the controller.

[0014] Preferably, the vibrating wheel assembly includes an axle, a mounting frame, and several vibrating wheels; the axle is rotatably mounted on the frame at the bottom of the conveyor belt, the mounting frame is fixedly sleeved on the axle, and the several vibrating wheels are evenly spaced and rotated around the axle along its circumference; one end of the axle of the vibrating wheel assembly of the first screening section and the second screening section extends to the outside of the frame to form a connecting end, and a sprocket is sleeved on the connecting end, and a synchronous belt connects the sprockets of the two axles; a first drive wheel is sleeved on one of the axles of the two axles, and a second drive motor is connected to the first drive wheel through a drive belt.

[0015] Preferably, the conveyor belt includes two sub-conveyor belts and several separating screen rods; the two sub-conveyor belts are arranged in parallel relative to each other, and several separating screen rods are evenly distributed between them; the separating screen rods are covered with a rubber cushioning elastic layer; the rubber cushioning elastic layer is coated with a silicone coating on the outside.

[0016] Preferably, the frame of the second screening section is provided with several mounting slots along the chute, and the potato collecting plate is movably installed in the mounting slot; an elastic buffer curtain is detachably installed between the outlet end of the conveying channel and the potato collecting plate; the frame is provided with several buffer zones along the potato tuber conveying trajectory at the outlet side of the conveying channel, and the buffer zones are provided with inflatable buffer components, and pressure sensors are installed on the buffer components.

[0017] Preferably, amplitude adjustment components are installed on the frames of the two conveying and screening sections. The amplitude adjustment components include an adjustment servo motor, an adjustment shaft, and adjustment wheels. The adjustment shaft is rotatably mounted on the frame, and several adjustment rods are fixedly mounted on its shaft towards the conveyor belt. Adjustment wheels are installed at the ends of the adjustment rods. The adjustment servo motor is fixedly mounted on the frame, and its power end is connected to the adjustment shaft. One end of the adjustment shaft extends to the outside of the frame to form an extension end. An indicator rod is installed on the extension end perpendicular to the direction of the adjustment shaft. An amplitude level indicator is installed on the frame at the corresponding position of the indicator rod. The adjustment servo motor is electrically connected to the controller.

[0018] Preferably, a humidity sensor is installed on the inlet side of the conveyor belt, a potato tuber size image sensor is installed on the frame at the inlet side of the conveyor channel, and a potato tuber status sensor is installed on the frame at the outlet side; the humidity sensor, potato tuber size image sensor, and potato tuber status sensor are electrically connected to the controller; the sensing elements include a torque sensor and a speed sensor; there are two torque sensors, two speed sensors, and two frequency converters; the two torque sensors are electrically connected to the first drive motor; the two speed sensors are installed on both sides of the conveyor belt; the two frequency converters are electrically connected to the first drive motor and the second drive motor respectively; the humidity sensor, potato tuber size image sensor, potato tuber status sensor, torque sensor, and speed sensor are electrically connected to the controller via shielded wires, and the shielded wires are grounded to the frame; the controller is equipped with an audible and visual alarm device.

[0019] This invention also provides an experimental method using a multi-parameter control test bench for loss reduction during combined potato harvesting, comprising the following experimental steps: S1. Reliability test of the sensing components before the test: Select torque sensors and speed sensors, and use the controller to simultaneously collect data from the two torque sensors and two speed sensors, and synchronously feed the data back to the controller. The effectiveness of the sensors is judged by data comparison. Repeated tests are conducted using qualified and unqualified sensors, and the response values ​​of abnormal scenarios generated during the data transmission of the sensing components are recorded to establish a sensor alarm threshold database. The electrical connection harness is shielded and the grounding resistance is tested. The electromagnetic interference environment in the field is simulated, and the fluctuation amplitude of the sensor data is monitored to ensure the stability of the communication bus between the sensing components and the controller, and to avoid the high-frequency interference of the frequency converter from affecting the signal transmission. The communication response time between the controller and the two frequency converters is tested to verify the stability of the signal closed loop, and the emergency protection actions are recorded. S2. Basic test of potatoes: Adjust the length of the second screening section of the conveyor belt to the initial length, and adjust the tilt angle of the box by adjusting the ball screw; then set the basic parameters of the test bench through the controller. The basic parameter settings of the test bench include setting the inverter parameters through the controller to set the speed range of the conveyor belt and the rotation speed range of the vibrating wheel; setting the speed controller parameters to set the feeding speed range of the conveyor belt; and setting the maximum torque stop threshold. During the experiment, a conveyor belt was selected to feed the tubers. The humidity sensor, tuber size image sensor, and tuber status sensor were turned off. Only the torque sensor value was used as the basis for determining the amount of tubers fed. The experiment was repeated by changing the amount of tubers fed and the torque range under different weights was recorded. The separation efficiency, tuber damage rate, and impurity content were statistically analyzed to establish a torque gradient control database. During repeated experiments, the ball screw was adjusted to adjust the tilt angle of the chamber before the experiment was conducted to improve the reliability of the test results. S3. Automatic Amplitude Adjustment Test: Based on the S2 test, the tuber status sensor is activated, and a high-speed camera is used to record the movement trajectory of the tubers. The operating parameters of the servo motor are set by the controller to set the amplitude adjustment range. The data from the tuber status sensor is used as the basis for judging the tuber-soil separation state. The amplitude is continuously adjusted by adjusting the servo motor to drive the adjustment wheel. The test is repeated by changing the tubers with different soil contents, adapting the length of the second screening section, and adjusting the operating parameters to establish a four-dimensional automatic adjustment database of "torque-soil content-screen length-amplitude". S4. Potato Collection Buffer Test: Based on the S3 test, the pressure sensor of the buffer zone is turned on. By changing the type of potato and the size of the potato, the pressure sensor of each buffer zone is used as the basis for determining the inflation amount of the corresponding inflatable buffer. Repeated tests are conducted by changing the type of potato and the size of the potato to establish a database of the inflation amount of the buffer buffer. S5. Dynamic Adjustment Test for Potato Screening: Based on the S4 test, the humidity sensor and potato tuber size image sensor are turned on to achieve synchronous reception of multi-variable data. The operating parameters of the first drive motor, the second drive motor, and the servo motor are set through the controller. The humidity sensor and the potato tuber size image sensor are used as the basis for judging the potato specifications. The potato specifications are changed and repeated tests are conducted. The control effect is verified through repeated tests. A dynamic adjustment database for potato screening is established and replaces the torque gradient control database in S2 to achieve adaptive control under all working conditions.

[0020] Beneficial Effects: 1. The multi-parameter control test bench for potato combined harvesting, separation, and loss reduction of the present invention forms a potato conveying channel by setting a conveyor belt driven by a first drive motor on the frame. A vibrating wheel driven by a second drive motor is set at the bottom of the conveyor belt to drive the conveyor belt to vibrate up and down, forming a vibrating potato screening and conveying channel. The control components of the test bench of the present invention include a controller, sensors, and a frequency converter. The sensors are installed on the first drive motor and the conveyor belt to sense the torque of the first drive motor and the rotational speed of the conveyor belt, so as to use the torque of the power end of the conveyor belt sensed by the sensors as the basis for determining the amount of potato feed. The frequency converter is electrically connected to the first drive motor and the second drive motor respectively. The controller outputs control signals in gradients, and the frequency converter regulates the conveying speed and vibration frequency of the conveyor belt, which can effectively adapt to the dynamic feed amount for real-time regulation, with timely regulation response, improving the potato-soil separation effect and reducing potato damage.

[0021] 2. Based on the foregoing, the frame of this invention includes a conveyor belt, a base, and a housing. The housing includes two side plates mounted on the base, with a rotating shaft rotatably mounted between them. The conveyor belt is fitted onto the rotating shaft to form a potato conveying channel. The conveyor belt is installed on the inlet side of the conveying channel, while a potato collecting plate is installed on the outlet side of the conveying channel. The conveyor belt of this invention is equipped with a conveying motor, and a speed controller is also installed on the conveyor belt. The conveying motor and the speed controller are electrically connected to a controller to achieve real-time monitoring and dynamic response. The torque sensor transmits data to the controller in real time, enabling stepless adjustment between the conveying speed, vibration frequency, and potato feeding speed of the conveyor belt, and timely response to fluctuations in the feeding amount.

[0022] 3. Based on the foregoing, the present invention features a secondary support wheel rotatably mounted on the frame, with the conveyor belt sleeved around the outer side of the secondary support wheel. The conveyor belt is divided into two conveying and screening sections by the secondary support wheel. A vibrating wheel assembly is installed on the frame at the location of each conveying and screening section. The section located at the conveyor belt inlet is the first screening section, and the section at the outlet is the second screening section. The shaft of the second screening section is slidably mounted on the frame, achieving a two-stage potato-soil separation screening section and an adjustable screening area design. The first screening section is a fixed structure, while the second screening section has an adjustable length. The screening area can be adjusted by changing the length of the second screening section to accommodate different potato-soil mixing amounts. Simultaneously, the two conveying and screening sections are driven by a second drive motor for vibration. With the amplitude adjustment component, different amplitudes can be output at the same vibration frequency, optimizing separation efficiency.

[0023] 4. Building upon the foregoing, the housing of this invention is hinged to the base on one side of the conveyor belt, while the base containing the housing on the side furthest from the conveyor belt is rotatably mounted with an adjusting ball screw. A stop plate is installed at the top of the adjusting ball screw. The side plates are made of transparent material. This allows for adjustment of the housing's tilt angle relative to the base via the ball screw. Compared to traditional manual mechanical adjustment, this provides precise control over tilt angle changes, ensuring consistency of test conditions for the conveyor belt at different tilt angles and improving the reliability of test results. Furthermore, the transparent material on both sides of the conveyor belt allows for full-angle observation and recording of potato tuber screening and movement trajectories. Real-time data collection of load and rotational speed via sensors provides comprehensive and accurate experimental data support for analyzing loss reduction patterns.

[0024] 5. Building upon the foregoing, the conveyor belt of this invention utilizes a separation screen rod connected between sub-conveyor belts on both sides. In addition to a rubber buffer layer wrapped around the outside of the separation screen rod, a silicone coating is added to enhance the surface elasticity and wear resistance of the separation screen rod, thereby reducing damage to the potato tubers. Simultaneously, to further reduce damage to the potato tubers in the collecting area, this invention adds a buffer curtain between the outlet side of the conveyor channel and the collecting plate. Preferably, the buffer curtain is made of highly elastic nylon, and its height can be adjusted according to the size of the potato tubers to slow their descent. Furthermore, this invention establishes several buffer zones along the potato tuber conveying trajectory at the outlet side of the conveyor channel on the frame. These buffer zones are equipped with inflatable buffer components, each fitted with a pressure sensor. This creates a zoned inflatable buffer structure in the collecting area, dividing the area into multiple independent buffer zones based on the potato tuber conveying trajectory. The inflation amount of the buffer component in each zone is controlled by a pressure sensor, ensuring that potato tubers falling from different positions receive appropriate buffering, reducing damage to the tubers.

[0025] 6. Building upon the foregoing, the sensing element of this invention further incorporates a humidity sensor and a tuber size image sensor. This allows for adaptation to various experimental variables through increased control parameters, enabling the test bench of this invention to operate stably under different soil moisture levels and tuber sizes, improving separation efficiency and preventing incomplete separation of tubers and soil due to high humidity and large size. Simultaneously, a tuber status sensor is installed at the outlet side of the conveyor channel to collect real-time data on the tuber-soil separation status, such as the amount of fine soil residue and the movement status or trajectory of the tubers. Preferably, the tuber status sensor of this invention is an image sensor, feeding the sensing data back to the controller. The controller automatically calculates the optimal amplitude value based on the sensing data and drives the regulating servo motor in real-time to adjust the amplitude of the conveyor belt, eliminating the response lag problem inherent in traditional manual amplitude adjustment. The amplitude response time of this invention is reduced from minutes to seconds, avoiding fluctuations in separation efficiency due to human error and reducing tuber damage rate.

[0026] 7. Building upon the foregoing, the torque sensor and speed sensor of this invention employ a dual-sensor structure. Both sensors simultaneously acquire data, and the controller compares the data to determine the sensor's validity, thus preventing control failure due to a single sensor malfunction. Furthermore, to ensure the accuracy of data transmission between the sensing element and the controller, the sensor data transmission line design is optimized, using shielded wires and adding grounding to reduce the impact of electromagnetic interference on data transmission.

[0027] 8. This invention provides an experimental method for a multi-parameter control test bench for potato combined harvesting and loss reduction. Reliability tests on the sensors before the experiment ensure their effectiveness and verify the alarm threshold of the alarm device. Multiple experiments are then conducted to establish a torque gradient control database, using the torque of the first drive motor as the core to determine the potato feeding amount and outputting control signals in gradients. Next, the potato tuber status sensor, humidity sensor, and potato tuber size image sensor are gradually activated to simulate actual potato screening operations. A multi-dimensional dynamic adjustment database for potato screening, encompassing torque, humidity, potato tuber size, conveyor belt speed, vibration frequency, and amplitude, is established to adapt to simulated actual potato screening experiments and improve the test bench's versatility. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the multi-parameter control test bench for potato harvesting separation and loss reduction in an embodiment. Figure 2 A top view of the structure of the multi-parameter control test bench for potato combined harvesting and loss reduction in an embodiment; Figure 3 The rear view of the structure of the multi-parameter control test bench for potato harvesting separation and loss reduction in an embodiment; Figure 4 This is a schematic diagram of the structure of the multi-parameter control test bench for potato harvesting separation and loss reduction in an embodiment (one of the two side plates is not shown). Figure 5 A schematic diagram of the conveyor belt assembly of the multi-parameter control test bench for potato harvesting separation and loss reduction in an embodiment; Figure 6 This is a schematic diagram of the conveyor belt and vibrating wheel assembly of the multi-parameter control test bench for potato combined harvesting, separation, and loss reduction in an embodiment. Figure 7 A schematic diagram of the conveyor belt and amplitude adjustment assembly of the multi-parameter control test bench for potato combined harvesting, separation and loss reduction in an embodiment; Figure 8 A schematic diagram of the amplitude adjustment component of the multi-parameter control test bench for potato combined harvesting and loss reduction in an embodiment; Figure 9A schematic diagram of the torque gradient control process of the multi-parameter control test bench for potato combined harvesting separation and loss reduction in an embodiment;

[0029] Figure 10 This is a schematic diagram of the controller of the multi-parameter control test bench for potato combined harvesting separation and loss reduction, as shown in the example.

[0030] In the diagram: 1. Frame; 2. Conveyor belt assembly; 3. Conveyor belt; 4. Rotary shaft; 5. First drive motor; 6. Second drive motor; 7. Vibrating wheel; 8. Conveying belt; 9. Base; 10. Side plate; 11. Potato collecting plate; 12. Torque sensor; 13. Reducer; 14. Secondary support wheel; 15. First screening section; 16. Second screening section; 17. Slide chute; 18. Adjusting ball screw; 19. Axle; 20. Mounting frame; 22. Synchronous chain; 23. Sub-conveyor belt; 24. Separating screen bar; 25. Adjusting shaft; 26. Adjusting wheel; 27. Adjusting rod; 28. Indicator rod; 29. ​​Amplitude level indicator; 30. Synchronous chain. Detailed Implementation

[0031] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the embodiments.

[0032] Please see Figures 1-8This embodiment provides a multi-parameter control test bench for potato combined harvesting and loss reduction, including a frame 1, a conveyor belt assembly 2, and a test assembly. The conveyor belt assembly includes a conveyor belt 3, three rotating shafts 4, a first drive motor 5, a vibrating wheel assembly, and a second drive motor 6. The three rotating shafts are rotatably mounted on the frame, with one shaft mounted on the inlet side of the conveyor belt, another shaft mounted on the outlet side of the conveyor belt, and the remaining shaft mounted on the frame between the two. The conveyor belt is sleeved on the outside of the rotating shafts. The power end of the first drive motor is connected to the rotating shaft on the outlet side of the conveyor belt to form a conveying channel. The vibrating wheel assembly has a vibrating wheel 7, which is eccentrically mounted on the bottom side of the conveyor belt. The second drive motor 6 is mounted on the frame, and its power end is connected to the vibrating wheel to drive the conveyor belt. The conveyor belt vibrates radially in a reciprocating manner. The test assembly includes a PLC controller, sensors, and frequency converters. In this embodiment, the sensors include a torque sensor and a speed sensor. The torque sensor is connected to the first drive motor, and the speed sensor is mounted on the frame on the side of the conveyor belt with its sensing end facing the conveyor belt to sense the torque of the first drive motor and the speed of the conveyor belt. There are two frequency converters, namely frequency converter 1 and frequency converter 2, with output power of 2.2kW and 1.1kW respectively. The 2.2kW frequency converter is electrically connected to the first drive motor, and the 1.1kW frequency converter is electrically connected to the second drive motor. The sensors, frequency converters, first drive motor, and second drive motor are all electrically connected to the PLC controller. The PLC controller used in this embodiment is a Siemens S7-1200 PLC. The torque sensor is a Dayang high-precision dynamic torque sensor with a range of 0-200 N·m, and the speed sensor uses an encoder for speed sensing.

[0033] The frame of this embodiment includes a conveyor belt 8, a base 9, and a housing. The housing is mounted on the upper side of the base and includes two side plates 10. The two side plates are mounted parallel to each other on the base, and three rotating shafts are mounted parallel to each other between the two side plates. The conveyor belt is mounted on the inlet side of the conveying channel, and a potato collecting plate 11 is mounted on the outlet side of the conveying channel. One side shaft of the rotating shaft on the outlet side of the conveyor belt extends to the outside of the side plate to form a mounting end, and a drive sprocket is mounted on the mounting end. The power output shaft coupling of the first drive motor is connected to the torque sensor 12, and the other end of the torque sensor is connected to the reducer 13 through a coupling. A power sprocket is mounted on the output end of the reducer, and it is connected to the drive sprocket through a drive chain. Driven drive sprockets are mounted on the remaining rotating shafts, and a synchronous chain 30 is connected between the driven drive sprockets. In this embodiment, a secondary support wheel 14 is rotatably mounted between two side plates near the middle of the conveyor belt on the housing. The conveyor belt is sleeved on the outside of the secondary support wheel, dividing the conveyor belt into two conveying and screening sections with the secondary support wheel as the boundary. A vibrating wheel assembly is installed on the frame at the location of each conveying and screening section. The conveying and screening section located on the inlet side of the potato conveying channel is defined as the first screening section 15, and the conveying and screening section located on the outlet side of the potato conveying channel is defined as the second screening section 16. A chute 17 is opened on the frame of the second screening section located on the outlet side of the potato conveying channel. The rotating shaft at the end of the second screening section is slidably mounted on the chute to form a conveyor belt length adjustable structure. In this embodiment, the first screening section is a fixed length structure with a screening length of 800mm, while the second screening section is a length adjustable mechanism. Its length can be selected as 1000mm, 1300mm, and 1600mm according to the potato screening requirements of different potato-soil mixing amounts. The length can be switched by adjusting the installation position of the rotating shaft on the outlet side of the conveyor belt. In addition, in this embodiment, the box body located on the side of the conveyor belt is hinged to the base via pivots on two side plates, while the box body on the side away from the conveyor belt is rotatably mounted on the base with an adjusting ball screw 18. The adjusting ball screw is driven by a screw motor (not shown), and a stop plate is installed at the top of the adjusting ball screw. The screw motor drives the ball screw to rotate, thereby causing the stop plate at the top of the screw to push the box body relative to the base to adjust the screening angle within the range of 15°-35°. In this embodiment, the two side plates 10 are made of transparent acrylic sheets; the conveyor belt is equipped with a conveyor motor and a speed controller, and the conveyor motor and speed controller are electrically connected to the PLC controller. Since the second screening section in this embodiment has an adjustable length structure, the potato collecting plate on its outlet side needs to be set to be movable to adapt to the second screening section. Specifically, the frame where the chute of the second screening section is located has several mounting slots along the chute, and the potato collecting plate is movablely installed in the mounting slots. An elastic buffer curtain (not shown) is detachably installed between the outlet end of the conveying channel and the potato collecting plate; the frame is located on the outlet side of the conveying channel and has 3-4 buffer zones along the potato tuber conveying track. The buffer zones are equipped with inflatable air column bags, and pressure sensors are installed on the air column bags.

[0034] The vibrating wheel assembly of this embodiment includes a wheel axle 19, a mounting frame 20, and two vibrating wheels 7. The wheel axle is rotatably mounted on the frame on the bottom side of the conveyor belt, and the mounting frame is fixedly sleeved on the wheel axle. The two vibrating wheels are evenly spaced around the wheel axle and rotated on the mounting frame. The shafts of the vibrating wheel assemblies of the first screening section and the second screening section extend to the outside of the frame on the same side to form a connecting end. A sprocket is sleeved on the connecting end, and a synchronous chain 22 is connected between the sprockets of the two wheel axles. A first drive sprocket is sleeved on the wheel axle located on the inlet side of the conveyor belt. The power end of the second drive motor is connected to the reducer through a coupling, and the output end of the reducer is connected to the first drive sprocket through a drive chain.

[0035] Furthermore, the conveyor belt 3 in this embodiment includes two sub-conveyor belts 23 and a plurality of separating screen rods 24; the two sub-conveyor belts are arranged in parallel relative to each other, and a plurality of separating screen rods are evenly distributed between them; the separating screen rods are covered with a rubber buffer elastic layer; the rubber buffer elastic layer is coated with a silicone coating on the outside.

[0036] In this embodiment, to adapt to the potato-soil separation process and automatically adjust the amplitude, amplitude adjustment components are installed on the frames of the two conveying and screening sections. Each amplitude adjustment component includes an adjustment servo motor (not shown), an adjustment shaft 25, and an adjustment wheel 26. The adjustment shaft is rotatably mounted on the frame, and an adjustment rod 27 is fixedly installed on its shaft at a position corresponding to the sub-conveyor belt of the conveyor belt. An adjustment wheel is installed at the end of the adjustment rod. The adjustment servo motor is fixedly mounted on the frame. One end of the adjustment shaft extends to the outside of the side plate of the frame to form a connecting end, and a connecting sprocket is installed on the connecting end. A sprocket is installed on the power end of the adjustment servo motor, and the sprocket is connected to the connecting sprocket of the adjustment shaft via a connecting chain. The other end of the adjustment shaft extends to the outside of the frame to form an extension end, and an indicator rod 28 is installed on the extension end perpendicular to the direction of the adjustment shaft. An amplitude level indicator 29 is installed on the frame at a position corresponding to the indicator rod. The adjustment servo motor is electrically connected to the PLC controller.

[0037] To simulate a real-world potato screening scenario, this embodiment incorporates multivariate influences to achieve an adaptive control model. A humidity sensor is installed at the inlet of the conveyor belt, a potato size image sensor is installed on the frame at the inlet of the conveyor channel, and a potato status sensor is installed on the frame at the outlet. These sensors are electrically connected to the PLC controller. The sensing elements in this embodiment include two torque sensors and two speed sensors. The torque sensors are electrically connected to the output drive shaft of the first drive motor. The two speed sensors are installed on both sides of the conveyor belt. The humidity sensor, potato size image sensor, potato status sensor, torque sensor, and speed sensor are electrically connected to the PLC controller via an external RS485 data bus with a shielded layer, and the data bus is grounded to the frame. The PLC controller is equipped with an audible and visual alarm.

[0038] This embodiment also provides an experimental method using a multi-parameter control test bench for loss reduction during combined potato harvesting, including the following experimental steps: S1. Reliability test of the sensing components before the experiment: Two identical Dayang high-precision dynamic torque sensors and two encoders were selected. Data from the two torque sensors and two encoders were simultaneously collected by a Siemens S7-1200 PLC controller, and the data was synchronously fed back to the controller. The effectiveness of the sensors was judged by data comparison. Repeated tests were conducted using qualified and unqualified sensors, and the response values ​​of abnormal scenarios such as signal loss and data jumps that may occur during the data transmission of the sensing components were recorded to establish a sensor alarm threshold database. The electrical connection harness was shielded, and the grounding resistance was tested. The electromagnetic interference environment in the field was simulated to monitor the fluctuation range of sensor data, ensure the stability of RS485 data bus communication, and avoid the high-frequency interference of the frequency converter from affecting signal transmission. The communication response time between the PLC and the 2.2kW and 1.1kW frequency converters was tested to verify the stability of the signal closed loop and record the emergency protection actions. In this embodiment, the PLC controller used the data comparison method to take the average value of the data difference between the two sensors if the difference is less than 5%; if the difference is greater than 5%, a sensor fault alarm was triggered.

[0039] S2. Basic Test for Potatoes: The length of the second screening section of the conveyor belt was adjusted to an initial length of 1000mm. The inclination angle of the box was adjusted to 15° by adjusting the ball screw. The basic parameters of the test bench were then set through the controller. The basic parameters of the test bench were set through the controller, including setting the parameters of the 2.2kW frequency converter to set the speed range of the conveyor belt to 0.5-2m / s, setting the parameters of the 1.1kW frequency converter to set the speed range of the second drive motor controlling the vibrating wheel to 150-300r / min, and setting the parameters of the speed controller to set the feeding speed range of the conveyor belt to 0.5-1.5m / s. At the same time, the maximum torque shutdown threshold was set as the shutdown protection parameter when the torque is ≥70N・m. During the experiment, a conveyor belt was used to feed the tubers. The humidity sensor, tuber size image sensor, and tuber status sensor were turned off. Only the torque sensor reading was used to determine the tuber feed amount. Repeated experiments were conducted with varying tuber input amounts, and the torque range under different weights was recorded. Separation efficiency, tuber damage rate, and impurity levels were simultaneously analyzed. Based on the experimental data, a torque gradient control database was established, clarifying the separation screen speed, vibration frequency, and feeding speed parameters corresponding to each torque range. (See reference...) Figures 9-10 . Figure 9 In this context, Tn represents torque, and n represents the rotational speed of the vibrating wheel. During repeated tests, the ball screw is adjusted to change the tilt angle of the housing before further testing to improve the reliability of the test results.

[0040] S3. Automatic Amplitude Adjustment Test: Based on the S2 test, the tuber status sensor is activated, and the operating parameters of the servo motor are set through the controller to set the amplitude adjustment range to 0-70mm. The data from the tuber status sensor is used as the basis for determining the tuber-soil separation state. The amplitude is continuously adjusted by adjusting the servo motor to drive the adjustment wheel. The test is repeated by changing the tuber with different soil contents, adapting the length of the second screening section, and adjusting the operating parameters. The test data is integrated to establish a four-dimensional automatic adjustment database of "torque-soil content-screen length-amplitude", replacing the original manual amplitude adjustment handle operation logic. In this embodiment, the amplitude adjustment is achieved by installing small adjustment servo motors, preferably stepper motors, on the two conveying screening sections and connecting them to the PLC controller via RS485 bus. A tuber status sensor is added at the end of the second screening section to collect the tuber-soil separation state in real time (such as the amount of fine soil residue and the stability of tuber movement), and the data is transmitted to the PLC. The PLC automatically calculates the optimal amplitude value and drives the adjustment servo motor to adjust the amplitude adjustment wheel to achieve stepless automatic amplitude adaptation.

[0041] S4. Potato Collection Buffer Test: Based on the S3 test, the pressure sensor of the buffer zone is turned on. By changing the type of potato and the size of the potato, the pressure sensor of each buffer zone is used as the inflation volume database of the corresponding inflatable air column bag to adapt to different sizes of potato (such as potatoes and sweet potatoes) and improve the versatility of the test platform.

[0042] S5. Dynamic Adjustment Test for Potato Screening: Based on the S4 test, the humidity sensor and potato tuber size image sensor are turned on. The operating parameters of the first drive motor, the second drive motor, and the servo motor are set through the PLC controller. The humidity sensor and the potato tuber size image sensor are used as the basis for judging the potato specifications. The potato specifications are changed and repeated tests are conducted. The control effect is verified through repeated tests. A dynamic adjustment database for potato screening is established and replaces the torque gradient control database in S2 to achieve adaptive control under all working conditions. This embodiment sets up two detection modules on the test bench: one is a potato soil moisture sensor (installed at the inlet of the conveyor belt, with a range of 0-100%RH), and the other is a potato tuber size image sensor (installed on the inlet side of the conveyor channel, which distinguishes the diameter of the potato tubers through image recognition, such as <50mm, 50-80mm, and >80mm). A multivariate correlation algorithm is embedded in the PLC control program to establish a multidimensional correspondence between "torque-humidity-potato tuber size-conveyor belt linear speed-vibration frequency" based on the previous experimental data, so as to establish a dynamic adjustment database for potato screening. When the test bench is running, the PLC simultaneously receives torque, humidity, and potato tuber size data, and automatically calls the database to match the optimal parameter combination, replacing the original torque gradient correspondence.

[0043] Working Principle: The multi-parameter control test bench for potato combined harvesting and loss reduction in this embodiment has a clear and practical control logic: the output drive shaft torque of the first drive motor is used as the core to determine the amount of potatoes fed into the conveyor belt. The PLC controller outputs control signals in gradients (e.g., torque < 30 N·m corresponds to a linear speed of 0.6 m / s and a vibration frequency of 7.5 Hz). The logic is simple and easy to understand, and can effectively adapt to actual operating scenarios. Real-time monitoring and dynamic response: The torque sensor transmits data to the PLC in real time. The PLC quickly sends instructions to the frequency converter and speed controller through the data bus to control the first drive motor, the second drive motor, and the conveyor motor. This achieves stepless adjustment of the conveyor belt's linear speed and vibration frequency, and the feeding speed of the conveyor belt is also synchronously adapted, enabling timely response to fluctuations in the feeding amount. Data acquisition and feedback closed loop: The frequency converters of the first and second drive motors and the speed sensors of the conveyor motor transmit feedback signals back to the PLC, forming a "monitoring-control-feedback" closed loop to ensure the accuracy of the control parameters and avoid deviations from the set values. It features basic safety protection: when the torque is ≥70 N·m, the system determines whether to stop feeding or gradually reduce the speed based on the conveyor belt rotation speed. This effectively prevents material blockage on the conveyor belt, reduces tuber compression damage, and ensures the safety of the equipment and test samples. The test bench in this embodiment can effectively adapt to dynamic feeding volume for real-time control, with timely adjustment, improving the tuber-soil separation effect and reducing tuber damage.

[0044] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A multi-parameter control test bench for potato combined harvesting and loss reduction, comprising a frame, a conveyor belt assembly, and a test assembly, characterized in that: The conveyor belt assembly includes a conveyor belt, several rotating shafts, a first drive motor, a vibrating wheel assembly, and a second drive motor. The rotating shafts are rotatably mounted on a frame, and the conveyor belt is fitted over the outside of the rotating shafts. The power end of the first drive motor is connected to one of the rotating shafts to form a conveying channel. The vibrating wheel assembly has a vibrating wheel, which is eccentrically mounted on the bottom side of the conveyor belt. The second drive motor is mounted on the frame, and its power end is connected to the vibrating wheel to drive the conveyor belt to reciprocate radially. The testing assembly includes a controller, sensors, and a frequency converter. The sensors are mounted on the first drive motor and the conveyor belt to sense the torque of the first drive motor and the rotational speed of the conveyor belt. The frequency converter is electrically connected to both the first and second drive motors. The sensors, the first drive motor, the second drive motor, and the frequency converter are all electrically connected to the controller.

2. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 1, characterized in that, The frame includes a conveyor belt, a base, and a housing. The housing is mounted on the upper side of the base and includes two side plates. The two side plates are mounted parallel to each other on the base, and several rotating shafts are rotatably mounted between the two side plates at intervals. The conveyor belt is mounted on the inlet side of the conveying channel, and a potato collecting plate is mounted on the outlet side of the conveying channel. One side of the rotating shaft connected to the first drive motor extends to the outside of the side plate to form a mounting end, and a drive wheel is mounted on the mounting end. The first drive motor is connected to the drive wheel via a drive belt, and driven drive wheels are mounted on the remaining rotating shafts, and synchronous belts are connected between the driven drive wheels.

3. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 2, characterized in that, A secondary support wheel is rotatably mounted on the frame, and the conveyor belt is sleeved on the outside of the secondary support wheel, dividing the conveyor belt into two conveying and screening sections with the secondary support wheel as the boundary. A vibrating wheel assembly is installed on the frame at the location of each conveying and screening section. The conveying and screening section located on the inlet side of the potato conveying channel is defined as the first screening section, and the conveying and screening section located on the outlet side of the potato conveying channel is defined as the second screening section. A chute is opened on the frame of the second screening section located on the outlet side of the potato conveying channel, and the rotating shaft at the end of the second screening section is slidably mounted on the chute to form an adjustable conveyor belt length structure.

4. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 2, characterized in that, The box body is hinged to the base on one side of the conveyor belt, and the base on the side of the box body away from the conveyor belt is rotatably mounted with an adjusting ball screw, and a stop plate is installed at the top of the adjusting ball screw; the side plate is made of transparent material; the conveyor belt is equipped with a conveyor motor, and a speed controller is installed on the conveyor belt, the speed controller is electrically connected to the conveyor motor, and the speed controller is electrically connected to the controller.

5. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 3, characterized in that, The vibrating wheel assembly includes an axle, a mounting frame, and several vibrating wheels. The axle is rotatably mounted on the frame at the bottom of the conveyor belt, and the mounting frame is fixedly sleeved on the axle. The several vibrating wheels are evenly spaced around the axle and rotated on the mounting frame. One end of the axle of the vibrating wheel assembly of the first screening section and the second screening section extends to the outside of the frame to form a connecting end. A sprocket is sleeved on the connecting end, and a synchronous belt connects the sprockets of the two axles. A first drive wheel is sleeved on one of the axles, and the second drive motor is connected to the first drive wheel through a drive belt.

6. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 1, characterized in that, The conveyor belt includes two sub-conveyor belts and several separating screen rods; the two sub-conveyor belts are arranged in parallel relative to each other, and several separating screen rods are evenly distributed between them; the separating screen rods are covered with a rubber cushioning elastic layer; the rubber cushioning elastic layer is coated with a silicone coating on the outside.

7. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 4, characterized in that, The frame of the second screening section is provided with several mounting slots along the chute, and the potato collecting plate is movably installed in the mounting slot; an elastic buffer curtain is detachably installed between the outlet end of the conveying channel and the potato collecting plate; the frame is provided with several buffer zones along the potato block conveying trajectory at the outlet side of the conveying channel, and the buffer zones are provided with inflatable buffer components, and pressure sensors are installed on the buffer components.

8. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 3, characterized in that, Amplitude adjustment assemblies are installed on the frames of the two conveying and screening sections. Each amplitude adjustment assembly includes an adjustment servo motor, an adjustment shaft, and adjustment wheels. The adjustment shaft is rotatably mounted on the frame, and several adjustment rods are fixedly mounted on its shaft towards the conveyor belt. The adjustment wheels are installed at the ends of the adjustment rods. The adjustment servo motor is fixedly mounted on the frame, and its power end is connected to the adjustment shaft. One end of the adjustment shaft extends to the outside of the frame to form an extension end. An indicator rod is installed on the extension end perpendicular to the direction of the adjustment shaft. An amplitude level indicator is installed on the frame at a position corresponding to the indicator rod. The adjustment servo motor is electrically connected to the controller.

9. The multi-parameter control test bench for potato combined harvesting and loss reduction according to claim 2, characterized in that, A humidity sensor is installed at the inlet side of the conveyor belt, a potato tuber size image sensor is installed on the frame at the inlet side of the conveyor channel, and a potato tuber status sensor is installed on the frame at the outlet side. The humidity sensor, potato tuber size image sensor, and potato tuber status sensor are electrically connected to the controller. The sensing elements include a torque sensor and a speed sensor. There are two torque sensors, two speed sensors, and two frequency converters. The two torque sensors are electrically connected to the first drive motor. The two speed sensors are installed on both sides of the conveyor belt. The two frequency converters are electrically connected to the first drive motor and the second drive motor, respectively. The humidity sensor, potato tuber size image sensor, potato tuber status sensor, torque sensor, and speed sensor are electrically connected to the controller via shielded wires, and the shielded wires are grounded to the frame. The controller is equipped with an audible and visual alarm device.

10. A test method using a multi-parameter control test bench for potato combined harvesting and loss reduction according to any one of claims 1-9, characterized in that, The following test steps are included: S1. Reliability test of the sensing components before the test: Select torque sensors and speed sensors, and use the controller to simultaneously collect data from the two torque sensors and two speed sensors, and synchronously feed the data back to the controller. The effectiveness of the sensors is judged by data comparison. Repeated tests are conducted using qualified and unqualified sensors, and the response values ​​of abnormal scenarios generated during the data transmission of the sensing components are recorded to establish a sensor alarm threshold database. The electrical connection harness is shielded and the grounding resistance is tested. The electromagnetic interference environment in the field is simulated, and the fluctuation amplitude of the sensor data is monitored to ensure the stability of the communication bus between the sensing components and the controller, and to avoid the high-frequency interference of the frequency converter from affecting the signal transmission. The communication response time between the controller and the two frequency converters is tested to verify the stability of the signal closed loop, and the emergency protection actions are recorded. S2. Basic test of potatoes: Adjust the length of the second screening section of the conveyor belt to the initial length, and adjust the tilt angle of the box by adjusting the ball screw; then set the basic parameters of the test bench by the controller. The basic parameter setting of the test bench includes setting the inverter parameters by the controller to set the speed range of the conveyor belt and the rotation speed range of the vibrating wheel. Set the speed controller parameters to set the feed speed range of the conveyor belt; at the same time, set the maximum torque stop threshold. During the experiment, a conveyor belt was selected to feed the tubers. The humidity sensor, tuber size image sensor, and tuber status sensor were turned off. Only the torque sensor value was used as the basis for determining the amount of tubers fed. The experiment was repeated by changing the amount of tubers fed and the torque range under different weights was recorded. The separation efficiency, tuber damage rate, and impurity content were statistically analyzed to establish a torque gradient control database. During repeated experiments, the ball screw was adjusted to adjust the tilt angle of the chamber before the experiment was conducted to improve the reliability of the test results. S3. Automatic Amplitude Adjustment Test: Based on the S2 test, the tuber status sensor is activated, and a high-speed camera is used to record the movement trajectory of the tubers. The operating parameters of the servo motor are set by the controller to set the amplitude adjustment range. The data from the tuber status sensor is used as the basis for judging the tuber-soil separation state. The amplitude is continuously adjusted by adjusting the servo motor to drive the adjustment wheel. The test is repeated by changing the tubers with different soil contents, adapting the length of the second screening section, and adapting the operating parameters to establish a four-dimensional automatic adjustment database of "torque-soil content-screen length-amplitude". S4. Potato Collection Buffer Test: Based on the S3 test, the pressure sensor of the buffer zone is turned on. By changing the type of potato and the size of the potato, the pressure sensor of each buffer zone is used as the basis for determining the inflation amount of the corresponding inflatable buffer. Repeated tests are conducted by changing the type of potato and the size of the potato to establish a database of the inflation amount of the buffer buffer. S5. Dynamic Adjustment Test for Potato Screening: Based on the S4 test, the humidity sensor and potato tuber size image sensor are turned on to achieve synchronous reception of multi-variable data. The operating parameters of the first drive motor, the second drive motor, and the servo motor are set through the controller. The humidity sensor and the potato tuber size image sensor are used as the basis for judging the potato specifications. The potato specifications are changed and repeated tests are conducted. The control effect is verified through repeated tests. A dynamic adjustment database for potato screening is established and replaces the torque gradient control database in S2 to achieve adaptive control under all working conditions.

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