To achieve rapid on-site detection of aflatoxin B1 (AFB1) in agricultural and sideline products, a portable detection system based on differential pulse voltammetry (DPV) and STM32F103ZET6 as the core processor was designed. The system consists of two main parts: hardware detection devices and a mobile App, which are connected through Wi-Fi communication. The hardware detection equipment includes a DPV waveform generation circuit, constant potential circuit, and micro current detection module. The upper computer App was developed in an Android environment and completed tasks such as signal acquisition and data storage. After completing the design, experiments were conducted to verify the accuracy of the constant potential circuit and micro current detection module. The constant potential circuit accurately applied the voltage set by the program to the electrode, with a maximum error of 4 mV. The micro current detection module converts the current into a voltage signal according to the theoretical formula and amplifies it according to the theoretical amplification factor. The laboratory-made AFB1 sensor was used to effectively detect AFB1 in the range of 0.1 fg/ml to 100 pg/ml. The maximum relative error between the test results in the standard solution and the electrochemical workstation CHI760e was 7.37%. Furthermore, peanut oil samples with different concentrations of AFB1 were tested, and the results were compared to the CHI760e detection results as the standard, with a recovery rate of 96.8%~106.0%. Peanut samples with different degrees of mold were also tested and compared with CHI760e, with a maximum relative error of 7.10%.The system's portability allows it to be easily transported to different locations for on-site testing, making it an ideal solution for testing in remote or rural areas where laboratory facilities may be limited. Furthermore, the use of a mobile App for data acquisition and storage makes it easy to track and manage testing results. In summary, this portable detection system has great potential for widespread application in the rapid on-site detection of AFB1 in agricultural and sideline products.
To meet the needs of environmental monitoring and regulation in rabbit houses, a real-time environmental monitoring system for rabbit houses was proposed based on narrow band Internet of Things (NB-IoT). The system overcomes the limitations of traditional wired networks, reduces network costs, circuit components, and expenses is low. An Arduino development board and the Quectel BC260Y-NB-IoT network module were used, along with the message queuing telemetry transport (MQTT) protocol for remote telemetry transmission, which enables network connectivity and communication with an IoT cloud platform. Multiple sensors, including SGP30, MQ137, and 5516 photoresistors, were integrated into the system to achieve real-time monitoring of various environmental parameters within the rabbit house, such as sound decibels, light intensity, humidity, temperature, and gas concentrations. The collected data was stored for further analysis and could be used to inform environmental regulation and monitoring in rabbit houses, both locally and in the cloud. Signal alerts based on circuit principles were triggered when thresholds were exceeded, creating an optimal living environment for the rabbits. The advantages of NB-IoT networks and other networks, such as Wi-Fi and LoRa were compared. The technology and process of building a system based on the three-layer architecture of the Internet of Things was introduced. The prices of circuit components were analyzed, and the total cost of the entire system was less than 400 RMB. The system underwent network and energy consumption tests, and the transmission stability, reliability, and energy consumption were reasonable and consistent across different time periods, locations, and network connection methods. An average of 0.57 transactions per second (TPS) was processed by the NB-IoT network using the MQTT communication protocol, and 34.2 messages per minute were sent and received with a fluctuation of 1 message. The monitored device was found to have an average voltage of approximately 12.5 V, a current of approximately 0.42 A, and an average power of 5.3 W after continuous monitoring using an electricity meter. No additional power consumption was observed during communication. The performance of various sensors was tested through a 24-hour indoor test, during which temperature and lighting conditions showed different variations corresponding to day and night cycles. The readings were stably and accurately captured by the environmental sensors, demonstrating their suitability for long-term monitoring purposes. This system is can provide equipment cost and network selection reference values for remote or large-scale livestock monitoring devices.
Solar insecticidal lamps (SILs) are widely used in agriculture for the purpose of effectively controlling pests and reducing pesticide dosage. With the increasing deployment of SILs, there are more and more reports about theft and destruction of SILs, seriously affecting the pest control effect and leading to great economic losses. Unfortunately, many efforts remain unsuccessful, since people can destruct the components of SIL in part but not steal the whole SIL, which cannot be detected by GPRS module or can only be labeled as a fault of component. To realize the broader effect of anti-theft and anti-destruction in the scenario of Solar Insecticidal Lamps Internet of Things (SIL-IoTs), there were two types of designs which would enable substantial improvements. On one hand, SIL was reformed and designed to obtain more information from different kinds of sensors and increase the difficulty of theft and destruction of SILs. Four modules were equipped including gated switch, voltage and current module, emergency power module, acceleration sensor module. Gated switch was used to judge whether the gate of power was open or closed. Voltage and current module of battery, solar panel, lamp, and metal mesh were used to judge whether the components were stolen or destructed. Emergency power module was used for communication module after the battery being stolen. Acceleration sensor module was used to judge whether the SIL was shaking by stealer. On the other hand, the auxiliary equipment of SIL, i.e., unmanned aerial vehicle insecticidal lamp (UAV-IL), was put forward for emergency applications after theft and destruction of SIL, e.g., deployment, tracking, patrol inspection, and so on. Through the above-mentioned hardware design and application of UAV-IL, more information from different kinds of sensors could be obtained to make judgements about the situation of theft and destruction. However, considering the short occurrence time of theft and destruction, the design was not enough to realize fast and accurate judgments. Therefore, six key research issues in the design of internal hardware, software algorithm and appearance structure design level were discussed, including 1) optimal design of anti-theft and anti-destruction of SILs; 2) establishment of anti-theft and anti-destruction judgment rules of SILs; 3) fast and accurate judgments of theft and destruction of SILs; 4) emergency measures after theft and destruction of SILs; and 5) prediction and prevention of theft and destruction of SILs; 6) optimal calculation to reduce the load of network data transmission. The anti-theft and anti-destruction have crucial roles in equipment safety, which can be extended to various agricultural applications.
In view of the demand of small and medium-sized farms for rapid monitoring and accurate diagnosis of crop growth, the National Engineering Research Center for Information Technology in Agriculture (NERCITA) designed a crop growth monitoring device which named CropSense. It is a portable crop health analysis instrument based on dual-channel high-throughput spectral signals which derived from the incident and reflected light intensity of the crop canopy at red and near-infrared bands. This paper designed and implemented a data collecting and analyzing system for CropSense. It consisted of a mobile application for collecting data of CropSense and a server-side system for data and model management. The system implemented data collecting, processing, analyzing and management completely. The system calculated normalized differential vegetation index (NDVI) based on the two-channels spectral sampling data from CropSense which connected smart phone by Bluetooth, then generated crop growth parameters about nitrogen content, chlorophyll content and Leaf Area Index with the built-in spectral inversion model in the server. Meanwhile, it calculated vegetation coverage, density and color content by images captured from the camera of smart phone. When we finished the sampling program, it generated growth parameter thematic maps by Kriging interpolation based on all sampling data of the selected fields. Considering the target yield of the plot, it could provide expert advice visually. Users could get diagnostic information and professional guiding scheme of crop plots immediately after collecting data by touch a button. Now the device and system have been applied in some experimental farms of research institutes. This paper detailed application of the system in XiaoTangShan farm of NERCITA. Compared with the traditional corn flare period samples and fertilize schemes, users could avoid errors caused by manual recording. Besides, with the same corn yield, the fertilization amount has reduced 16.67% when using the generation of the variable fertilization scheme by this system. The result showed that the system could get the crop growth status efficiently and produced reasonable fertilization. The system collected and analyzed crop growth efficiently and conveniently. It is suitable for various farmers without expertise to obtain the information of the crop growth timely and can guide them to operate more effectively and economically in the field. The system saved data to web server through the Internet which improved the shortcoming of poor sharing in the traditional data exporting mode. This system is practical and promising, and it will be widely applied in the explosion of family farms in China.
High-quality operation of plant protection UAV is the premise of precision operation in agricultural aviation, so it is particularly important to study the characteristics of spray system. In order to explore the factors that affect the spray quality, the comprehensive experimental platform of spray performance (developed by Jilin Agricultural Machinery Research Institute) was used to test the droplet deposition distribution and droplet diameter under different UAV rotor speed, spray height and centrifugal nozzle speed in this research, and regression analysis on the deposition characteristics and particle diameter data of 12 groups of tests was conducted. The results showed that the three repeated tests of the same set of parameters had good consistency. Droplets had obvious drift and the maximum effective deposition rate was 46.31% and minimum 31.74%, which shows that the effective deposition rate of droplets was lower than 50%. Compared with the regression analysis results of droplet diameters DV10, DV50 and DV90, the spray height P value is greater than 0.5, and the nozzle speed and rotor speed P value are less than 0.5. So it can be inferred that spray height had a very significant effect on deposition, no significant effect on droplet size. The nozzle speed and rotor speed had very significant effect on droplet size, no significant effect on deposition. The test results of this research can provide theoretical basis and data support for improving the operation quality and spraying efficiency of UAVs.
In recent years, the technology of automatic tractor navigation based on satellite positioning has greatly improved the efficiency and accuracy of tractor field work. Automatic steering contributes is one of the key technologies to realize the automation and intelligentization of agricultural mechanization. It costs much time to install and test automatic steering systems for tractors in the field due to complicated conditions. An automatic steering test bench was developed to reduce time consumed in the field by conducting simulation tests on accuracy and reliability. The developed automatic steering system can be applied to the tractor after obtaining satisfactory results on the test bench, which will greatly shorten the development cycle and improve the precision of the system. In this study, a 120-horsepower tractor front axle was selected. Through the design and calculation of mechanical structure, hydraulic system and electrical control system, the tractor automatic steering test bench was built. The mechanical body consist of a tractor front axle assembly, a loading device and a mechanical frame. The hydraulic interface was reserved for post-installation of automatic steering devices. Two inertial measurement units were used to test the steering system performance by recording the rotation angle of front wheels and the steering wheel. The steering wheel had a steering clearance of 16.48° and an average wheel delay time of 0.14s. In the general range and small angle range, there is a small deviation between the actual corner and the theoretical corner. Responsibility and stability met requirements for agricultural machinery steering. Experimental results show that the test bench has stable performance in terms of status detection, steering control and measurement analysis, which could meet requirements for verifying working parameters of automatic steering devices. The research provides an efficient and reliable test bench for commissioning and performance testing of agricultural machinery automatic steering.
With the development of computer and automation control technology, robots have gradually entered the field of agricultural production. The application of agricultural robots can improve labor productivity, product quality and working conditions, solve the problem of labor shortage, and promote the intellectualization of agricultural production process. Fruit harvesting is the most time-consuming and laborious part of agricultural production. Since the skin of fruit is relatively fragile, it is easy to cause damage in the process of grasping. Therefore, some flexibility is necessary for the grasping device. As the end of the picking, robot directly acts on the part of the grasping object, the manipulator has attracted more and more attention of scientific researchers because of its light weight, small size, low energy consumption, high flexibility and low cost. Manipulator is the core component of robot, which is installed on the end of picking robot and acting on the object directly. In order to improve universality and flexibility, reduce the damage to the fruits, and shorten the design cycle, the flexible manipulator with simple structure and self-adaptive function was designed to achieve favorable grasp of fruits. The manipulator developed based on 3D printing has the advantages of rapid prototyping, low experimental cost and easy to assemble, etc. Flexible manipulator consists of flexible finger, wrist, base and pneumatic components. Its general action process is opening, grasping, moveing and putting down. However, flexible manipulator combines the two processes of moving and putting down into swallowing, which reduces the execution of the motion and improves the grasping performance and efficiency of the manipulator. Pneumatic components and wrist were printed from flexible materials and the material is thermoplastic urethane and polylactic acid respectively. The wrist is an integral part with flexibility. The use of pneumatic components can achieve the wrist bending, driving flexible fingers self-adaptive deformation to grasp the fruit. The manipulator is placed on the vertical sliding platform of the four-wheel platform, which can move up and down, and the four-wheel platform can move freely in all directions. The single wrist has two rotational degrees of freedom. The kinematics model of single wrist was established by combining constant curvature deformation and D-H coordinate method. On this basis, the functional validation test and safety test of flexible manipulator were carried out. In the safety test, the thin pressure sensor was used as the detection element of the contact force signal between the finger and the grasping object. The experiment results show that the pneumatic components of the flexible manipulator meet the design requirements and the driving wrist is flexible. The manipulator has certain flexibility, and can adapt to the shape of the fruit for self-adaptive grasping. The self-adaptive grasping effect of the manipulator is remarkable, and the fruit skin is intact. Moreover, the flexible manipulator has a favorable self-adaptive function based on the structural design and the complexity of the control system is deduced. In addition, it will provide reference for the design of the flexible grasping mechanism.
