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Aiming at the problems of poor passability and adaptability, low tillage rate, grass entanglement of the knife roller, and poor straw burying performance in the traditional rotary tiller when tillage operations in the planting pattern of rapeseed under rice-rapeseed or rice-rice-rapeseed rotation planting, a driven disc plow and double-edged rotary tillage combined tiller was developed. A working method of active plow followed by double-edged rotary tillage and ditching on both sides was proposed. The main structural parameters of driven disc plow and the layout of driven disc plow-ditch device were determined. A double-edged rotary tillage device for driven disc plow and double-edged rotary tillage combined tiller was designed. The key structural parameters of double-edged rotary blade with long blade and short blade were determined according to sliding cutting principle. The arrangement of the double-edged rotary tillage blades were determined according to the structure layout of the driven disc plow group. The DEM simulation method was used to analyze the straw burial performance and soil exchange performance of the driven disc plow and double-edged rotary tillage combined tiller. The experiment showed that the average straw burial rate of the whole machine operation was 94.69% and the soil layer was evenly mixed after the whole machine worked. The field experiment showed that under the two conditions of high and low straw stubble, the average straw burial rate was 96.45% and the average soil crushing rate was 95.30% after the operation of the driven disc plow and double-edged rotary tillage combined tiller with double-edged rotary tillage device and knife roller did not twine grass. The field sowing test showed that the rapeseed emergence was uniform, and the indexes met the requirements of rapeseed direct seeding bed preparation in rice stubble field.