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Aiming at the high missing seed rate problem in the current hole-type wheel precision seed feeder, a friction adjustable precision seeder was designed for experimental sowing of wheat. Through the stress analysis of single seed seeding process, it was determined that the seed groove angle β of the seeding device was greater than 17.7°. Discrete element simulations were employed to identify the structural dimensions of key components in the seeder and to determine the optimal rotational speed range for the friction plate (with a seed furrow angle β of 30° and a hole wheel friction angle γ of 14°, the missing seed rate was the lowest when the friction plate speed was ranged from 20 r/min to 28 r/min). Through force analysis, simulation analysis and actual operation, the size range of the key structure of the seed feeder was determined. The three factors and three levels of regression response surface tests were carried out with the friction plate speed, hole wheel speed and pick gap as the main working parameters, and the pass rate of grain spacing, the leakage rate and the replay rate as evaluation indexes. The effects of each working parameter on the test indexes were analyzed by establishing the regression equation and the response surface mathematical model. Through parameter optimization, the optimal working parameters were found to be a hole wheel rotational speed of 6 r/min, a friction plate rotational speed of 24 r/min, and the distance between the baffle and the mold hole was 3.1 mm. Validation tests on this experimental combination yielded a particle spacing qualification rate of 89.13%, a missing sowing rate of 4.83%, and a reseeding rate of 6.04%. The experimental results deviated from the predicted values by approximately 1 percentage points, meeting the operational requirements for precise and minimal wheat planting. The research findings can provide technical support for the development of precision seeders for wheat experimental sowing.