| With the continuous improvement of the level of agricultural mechanization and the continuous enhancement of environmental protection awareness,the requirements for agricultural machinery and equipment are becoming higher and higher.As a big country of facility agriculture,China’s annual output value is nearly one trillion yuan,accounting for more than 85% of the total in the world.Therefore,facility agriculture is suited to inevitable trend and development direction of modern agricultural development.However,the current agricultural mechanization equipment is mostly fuel-powered,which not only may bring more pollution to the environment,but also can not work in the narrow areas of the land and greenhouse and other facility agricultural zone.Based on the traditional production technology of rotary cultivator,the development history of rotary cultivator at home and abroad was studied,and the existing problems of rotary cultivator were analyzed.Combined with the operating environment requirements of facility agriculture,a number of performance parameter requirements were analyzed,and an unmanned electric micro-tiller suitable for greenhouse was designed.This research has certain reference value for the research and development of new intelligent electric micro-tiller and the transforming and upgrading of traditional facility agriculture in China.Meanwhile,it has important practical guiding significance for the improvement of mechanization and intelligence level of agricultural environment with limited conditions such as facility agriculture in China.The main research contents of this paper are as follows:1.The greenhouse intelligent electric micro tillage machine overall scheme and working principle were introduced.In order to adapt to the working environment of the greenhouse,the electric micro-tiller is usually required to be suitable in size,stable in structure,reliable in operation,flexible and stable in operation and convenient in operation.Combined with the design requirements of the electric micro-tiller in the greenhouse,the pure mechanical transmission scheme of the electric micro-tiller was determined.The main structure of greenhouse electric micro-tiller was designed,including rotary tillage device,track chassis and key components of chassis,etc.The working principle of electric microtiller in greenhouse was introduced,which can enable the microtiller to realize basic functions such as walking,rotary tillage,rotary tillage lifting and so on.2.The design simulation and power calculation of key components of greenhouse intelligent electric micro-tiller were completed.In order to ensure that the electric micro-tiller has good working performance,according to the overall design plan and design requirements of the greenhouse electric micro-tiller,the passing performance,off-road performance,and stability of the electric micro-tiller were all analyzed.Then the rotary tillage device and crawler chassis of the greenhouse electric micro-tiller were designed,and the static simulation analysis of the rotary tillage device,crawler chassis and crawler tensioner were performed.Besides,considering to the requirements of rotary tillage in greenhouse environment,the technical parameters such as torque and pressure of rotary tillage were analyzed,and the key power units such as driving motor,electric push rod and power battery of electric micro-tillage machine were selected according to the calculated results.3.The design and ranging experiment of automatic positioning system of greenhouse intelligent electric micro-tiller were carried out.In order to solve the problems of low intelligentization degree of rotary tillage operation in greenhouse and safety accident prone in close range operation,the basic principle of UWB positioning technology was introduced,and the TODA and TWR positioning methods suitable for UWB positioning technology were analyzed.After comparison,TODA wireless positioning method with lower power consumption was selected.Then the main hardware modules of the positioning system were introduced,and the overall scheme and main operation interface of the UWB positioning system were designed.On this basis,the stability test of the positioning system was carried out,and the ranging data of the positioning system was collected and analyzed to verify the ranging reliability of the system,which can provide a reference for the positioning accuracy test of greenhouse electric micro-cultivator.4.The prototype production and comprehensive test analysis of greenhouse intelligent electric micro-tiller were finished.The stability test of the electric microtiller was carried out on the roll test bench to check whether it can run stably in a special greenhouse environment.In the soil tank for agricultural machinery test,the remote control function was used to carry out unmanned rotary tillage test on the intelligent electric micro tillage machine,which can check whether the rotary tillage depth and width of the electric micro tillage machine can meet the requirements of rotary tillage operation in the greenhouse.Then,the positioning precision test of electric micro tillage machine was carried out in a specific indoor environment by using the fixed coordinate test method to check the stability and precision of its positioning system.The test results showed that the various performances of electric micro tillage machine can meet the requirements of unmanned operation in the actual greenhouse environment.The greenhouse intelligent electric micro tillage machine designed in this paper can effectively solve the problems existing in the rotary tillage operation in the greenhouse environment,improve the quality and efficiency of the rotary tillage operation in the greenhouse,reduce the working intensity and operational risk of the operator,and adapt to the needs of greenhouse agricultural mechanization,green environmental protection,high quality and high efficiency. |
