Cleaning loss monitoring device of wheat combine harvester

Abstract

The invention relates to the technical field of grain loss monitoring, in particular to a wheat combine harvester cleaning loss monitoring device which comprises a collecting hopper, a two-way array type piezoelectric sensor, a vibration signal compensation device, a collision signal processing system and a man-machine interaction system. A plurality of outlets are formed in the bottom of the system, a plurality of groups of base boxes are arranged below the system, the bidirectional array type piezoelectric sensors and the vibration signal compensation devices are integrated in the base boxes, the collision signal processing system is composed of a signal amplification module and a TMS320F28335 core processor module, the signal amplification module amplifies electric signals output by the piezoelectric sensors and the vibration signal compensation devices, and the TMS320F28335 core processor module outputs the amplified electric signals. The core processor module carries out vibration signal compensation and collision grain recognition counting to obtain cleaning loss data, the man-machine interaction system achieves data transmission and display through the CAN communication module and the serial port display screen, and a driver can conveniently adjust operation parameters in real time.

Description

Technical Field

[0001] The invention relates to the technical field of grain loss monitoring, and in particular to a cleaning loss monitoring device for a wheat combine harvester. Background Art

[0002] As the world's largest grain crop, wheat plays a crucial role in global agricultural production. It is a staple food in many countries and regions, particularly in Europe, Asia, and North Africa. Wheat is the world's third-largest cereal grain, after corn and rice, and is also one of the world's most widely distributed, largest-grown, and most traded crops. Furthermore, wheat is easy to store and transport, making it a major commodity grain and a significant player in international grain trade. Therefore, from a global perspective, wheat plays a crucial role in both food production and trade. As the world's third-largest cereal grain, wheat provides 20% of the global population's protein and energy needs, playing a crucial role in global food security. As the world's largest wheat producer and consumer, my country's wheat industry plays a crucial role in the agricultural sector. As a major grain crop, wheat is crucial to ensuring national food security. However, my country's limited arable land resources make increasing planted area difficult, and wheat production increases face numerous challenges. In this context, reducing wheat loss and waste is a key measure to ensure food security and increase production. Mechanized harvesting is the primary way to improve wheat production efficiency and reduce labor intensity. However, during grain combine harvesting, cleaning losses are the primary source of losses, accounting for the largest proportion of total losses. Traditional mechanized harvesting loss measurement uses a five-point sampling method, with manual field sampling and measurement after the wheat harvest is complete. This method results in significant data lag, preventing operators from adjusting harvester operating parameters based on measured loss data in a timely manner, making it difficult to achieve the goal of reducing harvest losses.

[0003] Currently, monitoring devices based on machine vision and piezoelectric principles are widely used in the field of grain loss monitoring. Machine vision-based monitoring devices use a high-resolution camera installed at the combine harvester's waste outlet to capture real-time images of the discharge. An image processing system then performs binarization and median filtering on the captured images to identify lost kernels and calculate the amount of grain loss. Piezoelectric-based monitoring devices install piezoelectric sensors on the combine harvester. The discharged material impacts the sensors, causing the piezoelectric material inside to generate electrical signals with varying amplitudes and frequencies. The sensor's output is processed through amplification and acquisition, and relevant parameters such as peak value and frequency are used to identify lost kernels and calculate the amount of harvest loss. However, the complex and dusty working environment of the monitoring devices makes it difficult to capture clear images, resulting in limited effectiveness of current machine vision-based monitoring devices. Furthermore, existing grain loss monitoring sensors have a low saturation capacity and are susceptible to mechanical vibrations from the harvester. Summary of the Invention

[0004] In response to the above-mentioned defects and problems, the present invention provides a wheat harvester cleaning loss monitoring device, which aims to improve the monitoring capacity of the sensor and reduce the impact of mechanical vibration on the sensor. A bidirectional array piezoelectric sensor is used to reduce the impact of the harvester body vibration caused by the harvester itself and external factors on the grain collision sensor, thereby ensuring the monitoring accuracy of the harvester cleaning loss monitoring device; by increasing the number of grain collision signal output channels, the signal interference generated by multiple collision signals in the same output channel is reduced, thereby ensuring the monitoring accuracy of the cleaning loss monitoring device; in order to reduce the impact of mechanical vibration on the bidirectional array piezoelectric sensor during the operation of the harvester, a vibration signal compensation device is designed based on the piezoelectric sensor. By collecting the signal generated by the vibration in real time, it compensates the output signal of the bidirectional array piezoelectric sensor, thereby reducing the impact of mechanical vibration on the grain recognition accuracy.

[0005] The solution adopted by the present invention to solve its technical problems is: a wheat combine harvester cleaning loss monitoring device, including a collecting hopper, a bidirectional array piezoelectric sensor, a vibration signal compensation device, a collision signal processing system and a human-computer interaction system, the collecting hopper is installed at the impurity discharge port of the harvester cleaning device, the bottom of the collecting hopper is provided with multiple outlets, and multiple groups of base boxes are arranged below each outlet of the collecting hopper, the bidirectional array piezoelectric sensor and the vibration signal compensation device are integrated in the base box and are connected through the base plate on the top of the base box, the bidirectional array piezoelectric sensor is installed on the upper layer of the base plate, and the vibration signal compensation device is installed on the lower layer of the base plate; the collision signal processing system includes The invention comprises an electrically connected signal amplification module and a TMS320F28335 core processor module. The signal amplification module is electrically connected to a bidirectional array piezoelectric sensor and a vibration signal compensation device. The signal amplification module amplifies and processes the electrical signal output by the piezoelectric effect generated on the bidirectional array piezoelectric sensor and the electrical signal output by the mechanical vibration received by the vibration signal compensation device. The TMS320F28335 core processor module performs vibration signal compensation and collision grain identification and counting on the received data to obtain cleaning loss data. The human-computer interaction system is used to realize the interaction between the user and the collision signal processing system, and comprises a CAN communication module and a serial port display screen.

[0006] Furthermore, the bidirectional array piezoelectric sensor is composed of two parts: piezoelectric ceramics and sensor units. The piezoelectric ceramics are arranged in a matrix on the sensor units.

[0007] Furthermore, the bidirectional array piezoelectric sensor is arranged to be inclined at 45-60 degrees with respect to the horizontal direction.

[0008] Furthermore, the MS320F28335 core processor includes an analog-to-digital conversion module, an on-chip ADC conversion module, and an external ADC conversion module.

[0009] Furthermore, the CAN communication module realizes communication between the system and other devices through the CAN bus, and the serial port screen is installed in the cab to display the working status and measurement data of the system in real time.

[0010] Furthermore, the signal amplification module is composed of a charge amplification circuit and a voltage amplification circuit, and the charge amplification circuit and the voltage amplification circuit are integrated on a PCB board in the base box.

[0011] Beneficial effects of the present invention: Bidirectional array piezoelectric sensor: The matrix-arranged piezoelectric ceramics significantly increase the sensor's monitoring area and capacity, enabling more comprehensive capture of grain particle collision signals, reducing missed detection rates and thus improving the accuracy of cleaning loss monitoring. Vibration signal compensation device: monitors and compensates for the signals generated by mechanical vibration in real time, effectively compensating for the interference of mechanical vibration on sensor signals. By collecting vibration signals in real time and performing compensation processing, it reduces the impact of vibration noise on grain collision signals, significantly reduces the impact of harvester body vibration on grain recognition accuracy, improves the system's anti-interference ability, and further improves signal accuracy and reliability. Multi-channel signal processing: Increases the number of kernel collision signal output channels, reduces signal interference caused by multiple collision signals in the same channel, and ensures the monitoring accuracy of the cleaning loss monitoring device; Human-computer interaction system: Through the CAN communication module and serial port display, the system realizes real-time communication and data transmission with other devices. The serial port display provides an intuitive user interface, showing the system's operating status and measurement data in real time, facilitating user monitoring and operation. The driver can view the harvesting loss data in real time in the cab and adjust the harvester operating parameters in a timely manner to achieve the loss reduction target; In summary, the wheat combine harvester cleaning loss monitoring device of the present invention significantly improves the accuracy and reliability of cleaning loss monitoring by optimizing the sensor structure, signal processing technology and human-computer interaction system, enhances the system's anti-interference ability, realizes real-time data transmission and display, improves work efficiency, reduces labor intensity, has high economy and practicality, and provides an effective solution for wheat combine harvester cleaning loss monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 Schematic diagram of the internal structure of the base box of the present invention; Figure 3 Schematic diagram of the charge amplifier circuit of the present invention; Figure 4 Schematic diagram of the voltage amplification circuit of the present invention; Figure 5 This is a schematic diagram of the signal amplification module circuit of the present invention; Figure 6 This is a schematic diagram of a PCB manufacturing model of the present invention; Figure 7 It is a schematic diagram of the TMS320F28335 core board of the present invention; Figure 8 This is a schematic diagram of the CAN bus network wiring of the present invention; Figure 9 It is a schematic diagram of the serial port screen structure of the present invention.

[0013] In the figure: 1. Aggregate hopper; 2. Bidirectional array piezoelectric sensor; 3. Vibration signal compensation device; 4. Signal amplification module; 5. AD7606 analog-to-digital acquisition module; 6. Power module; 7. CAN communication module; 8. TMS320F28335 core processor module; 9. CAN bus; 10. Serial port screen; 11. Base box; 12. Baseboard. DETAILED DESCRIPTION

[0014] The present invention will be further described below with reference to the accompanying drawings and examples.

[0015] See also Figure 1-9The present invention provides a technical solution for a wheat combine harvester cleaning loss monitoring device. The hardware design is based on the monitoring requirements for wheat combine harvester cleaning loss data. First, a suitable piezoelectric material is selected, and the sensor structure is optimized to address the problems of existing loss monitoring sensors, such as low grain monitoring saturation capacity and susceptibility to mechanical vibrations of the harvester. Next, components are selected and the corresponding circuits are designed based on the piezoelectric sensor's output signal and signal processing requirements. Simultaneously, a reasonable data display interface is designed based on the loss data display requirements, and a suitable communication protocol is selected based on the needs for data interaction between the signal processing device and the data display interface. Finally, the various hardware structures are rationally assembled to build the hardware structure of the wheat combine harvester cleaning loss monitoring device. This structure can collect material collision signals, identify wheat grain collision signals, realize grain counting and loss data transmission, and ultimately present the cleaning loss data on the data display interface. A collaborative software and hardware solution is constructed based on the monitoring requirements. A real-time signal acquisition program is designed based on the hardware platform to accurately capture the grain collision piezoelectric sensor signals. To address the problem of harvester mechanical vibration interfering with sensor signals, digital filtering algorithms and signal feature extraction techniques are used to effectively reduce the impact of vibration noise on kernel collision signals, improving recognition and counting accuracy. To address the need for monitoring harvester losses, a visualization interface has been developed that includes real-time data waveforms, loss statistics, and historical trend analysis. Remote monitoring is enabled through a data communication module, enabling real-time monitoring of harvester losses. Example

[0016] according to Figure 1 As shown, a wheat harvester cleaning loss monitoring device mainly comprises a collecting hopper 1, a bidirectional array piezoelectric sensor 2, a vibration signal compensation device 3, a collision signal processing system, and a human-computer interaction system. The collecting hopper 1 is installed at the waste discharge port of the harvester cleaning device. The bottom of the collecting hopper 1 is provided with multiple outlets. Multiple sets of base boxes 11 are arranged below each outlet of the collecting hopper 1. The bidirectional array piezoelectric sensor 2 and the vibration signal compensation device 3 are integrated into the base boxes 11 and connected via a base plate 12 on the top of the base box 11. The upper layer of the base plate 12 is the bidirectional array piezoelectric sensor 2, which faces the outlet of the collecting hopper 1. Grain particles falling from the collecting hopper 1 can land on the bidirectional array piezoelectric sensor 2 on the upper layer of the base plate 12. The bidirectional array piezoelectric sensor 2 monitors the collision vibration signals of the grain particles. The lower layer of the base plate 12 is the vibration signal compensation device 3. The bidirectional array piezoelectric sensor 2 and the signal processing system are integrated into the base box 11 and fixed to the collecting hopper 1 via a connector. The carrier of the human-computer interaction system is a serial port screen 10, which is installed in the cab and connected to the collision signal processing system through the CAN bus 9 to transmit and display the loss data.

[0017] The base plate 12 on top of the base box 11 is tilted so that the bidirectional array piezoelectric sensor 2 is tilted at a 45-60° angle to the horizontal and arranged below the collecting hopper 1. The bidirectional array piezoelectric sensor 2 is composed of two parts: piezoelectric ceramics and sensor units. The sensor units are composed of multiple pieces and are arranged below each outlet of the collecting hopper 1. The piezoelectric ceramics are arranged in a matrix on the sensor units.

[0018] The vibration signal compensation device 3 includes a vibration sensor, a sensor interface for connecting to the vibration sensor and receiving the original signal output by the sensor, a signal amplifier for amplifying the weak signal output by the sensor to a level suitable for processing, filters for removing noise and interference from the signal, including low-pass filters, high-pass filters, and band-pass filters, as well as functional modules such as temperature compensation, frequency compensation, and phase compensation. An analog-to-digital converter (ADC) that compensates the signal as needed and converts the amplified and filtered analog signal into a digital signal, a digital signal processor (DSP) for further processing the digital signal, such as spectrum analysis and wavelet transform, and a feedback controller for real-time monitoring of the compensation effect and adjusting the compensation parameters as needed. The vibration signal compensation device 3 receives the mechanical vibration and outputs an electrical signal to compensate the bidirectional array piezoelectric sensor 2 on the upper layer of the substrate 12.

[0019] The collision signal processing system consists of two parts: a signal amplification module 4 and a TMS320F28335 core processor module 8. Both the TMS320F28335 core processor module 8 and the signal amplification module 4 are integrated into a base box 11. The TMS320F28335 core processor includes three modules: an analog-to-digital conversion module, an on-chip ADC conversion module, and an external ADC conversion module. The analog-to-digital conversion module converts the amplified analog signal into a digital signal for digital signal processing, digitizing the signal and providing basic data for subsequent digital signal processing. The ADC module integrated within the MS320F28335 directly converts the analog signal into a digital signal. The on-chip ADC module typically has high conversion speed and accuracy, meeting the requirements of real-time signal processing, reducing the need for external ADC modules, reducing system complexity and cost, and improving system integration and reliability. When the performance or channel count of the on-chip ADC module is insufficient, an external ADC module can be used to expand the system's signal processing capabilities, providing additional ADC channels or higher conversion accuracy to meet the needs of complex signal processing. The system is also provided with a power supply module 6 for powering the system and an AD7606 analog-to-digital acquisition module 5, which is mainly responsible for converting the amplified analog signal into a digital signal for subsequent digital signal processing.

[0020] The human-computer interaction system is used to realize the interaction between the user and the collision signal processing system. It mainly includes two parts: a CAN communication module 7 and a serial port screen 10. The CAN communication module 7 is integrated in the base box 11. The CAN communication module realizes communication between the system and other devices through the CAN bus 9, realizing real-time data transmission and remote monitoring; the serial port screen 10 is installed in the cab and is used to display the system's working status, measurement data and other information in real time, providing an intuitive user interface to facilitate users to monitor the system's operating status and measurement results in real time.

[0021] like Figure 3 、 Figure 4 and Figure 5 The signal amplification module 4 is composed of a charge amplification circuit and a voltage amplification circuit, which are integrated on a PCB in the base box 11. The signal amplification module 4 is electrically connected to the bidirectional array piezoelectric sensor 2 and the vibration signal compensation device 3. The signal amplification module 4 amplifies the weak electrical signal generated by the piezoelectric effect output by the wheat harvester's lost grains colliding on the bidirectional array piezoelectric sensor 2 and the electrical signal received by the vibration signal compensation device 3 from the mechanical vibration output to a suitable range.

[0022] The PCB of the signal amplification module 4 is the foundation of the collision signal processing system. It receives raw sensor signals, amplifies them, and performs preliminary processing. Its primary functions include receiving weak analog signals from collision sensors (such as accelerometers and force sensors), amplifying them to a level suitable for subsequent processing, removing high-frequency noise and low-frequency interference from the signal through filtering circuits to improve the signal-to-noise ratio, and performing necessary signal conditioning, such as bias adjustment and impedance matching, to meet the requirements of subsequent processing modules. Amplification and filtering make the signal more suitable for subsequent digital processing, ensuring that the sensor output signal can be effectively received and processed by the core processor module.

[0023] The collision signal processing system realizes high-precision processing and real-time monitoring of the collision signal through the collaborative work of the PCB board of the signal amplification module 4, the TMS320F28335 core processor module 8 and the human-computer interaction system.

[0024] In specific use, the present invention provides a wheat combine harvester cleaning loss monitoring device. The present invention adopts a bidirectional array piezoelectric sensor 2. The grains lost by the wheat harvester during cleaning collide with the bidirectional array piezoelectric sensor 2 to generate a piezoelectric effect and output a relatively weak electrical signal. At the same time, the vibration signal compensation device 3 receives the electrical signal output by the mechanical vibration. Both signals are amplified and processed to a suitable range by the signal amplification module 4. Then, the electrical signal is collected by the AD7606 analog-to-digital conversion module and converted into a digital signal, which is transmitted to the TMS320F28335 core processor module 8 via the serial peripheral interface. The core processor performs vibration signal compensation and collision grain identification and counting on the received data to obtain cleaning loss data, which is transmitted to the serial port display screen data display page via the CAN communication module 7 for display of the cleaning loss data. The driver can adjust the harvester operating parameters by observing the loss data on the serial port display screen, thereby achieving the purpose of reducing cleaning losses.

[0025] The above description is only a preferred embodiment of the present invention and does not limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A wheat harvester cleaning loss monitoring device, comprising a collecting hopper, a bidirectional array piezoelectric sensor, a vibration signal compensation device, a collision signal processing system, and a human-computer interaction system, characterized in that: The collecting hopper is installed at the debris discharge port of the harvester cleaning device, and multiple outlets are provided at the bottom of the collecting hopper. Multiple groups of base boxes are arranged below each outlet of the collecting hopper. The bidirectional array piezoelectric sensor and the vibration signal compensation device are integrated in the base box and connected through the base plate on the top of the base box. The bidirectional array piezoelectric sensor is installed on the upper layer of the base plate, and the vibration signal compensation device is installed on the lower layer of the base plate; the collision signal processing system includes an electrically connected signal amplification module, an AD7606 analog-to-digital acquisition module and a TMS320F28335 core processor module, and the signal amplification module is electrically connected to the bidirectional array piezoelectric sensor. The sensor and the vibration signal compensation device are electrically connected. The signal amplification module amplifies the electrical signal output by the piezoelectric effect generated by the bidirectional array piezoelectric sensor and the electrical signal output by the mechanical vibration received by the vibration signal compensation device. The AD7606 analog-to-digital acquisition module converts the amplified analog signal into a digital signal. The TMS320F28335 core processor module performs vibration signal compensation and collision grain identification and counting on the received data to obtain cleaning loss data. The human-computer interaction system is used to realize the interaction between the user and the collision signal processing system, and includes a CAN communication module and a serial port display screen.

2. The wheat combine harvester cleaning loss monitoring device according to claim 1, characterized in that: The bidirectional array piezoelectric sensor consists of two parts: piezoelectric ceramics and sensor units. The piezoelectric ceramics are arranged in a matrix on the sensor units.

3. A wheat combine harvester cleaning loss monitoring device according to claim 1 or 2, characterized in that: The bidirectional array piezoelectric sensor is arranged to be inclined at 45-60 degrees relative to the horizontal direction.

4. The wheat harvester cleaning loss monitoring device according to claim 1, characterized in that: The MS320F28335 core processor includes an analog-to-digital conversion module, an on-chip ADC conversion module, and an external ADC conversion module.

5. The wheat harvester cleaning loss monitoring device according to claim 1, characterized in that: The CAN communication module realizes communication between the system and other devices through the CAN bus. The serial port screen is installed in the cab and is used to display the system's working status and measurement data in real time.

6. The wheat combine harvester cleaning loss monitoring device according to claim 1, characterized in that: The signal amplification module is composed of a charge amplification circuit and a voltage amplification circuit, and the charge amplification circuit and the voltage amplification circuit are integrated on a PCB board in the base box.

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