基于DEM-MBD耦合的滚勺式精量穴播器成穴器运动参数优化

Optimization of the motion parameters of a rolling spoon type precision hole planter based on DEM-MBD coupling

关键词:  穴播器  成穴器  DEM-MBD耦合  仿真优化

Key words:  cavity seeders  cavity formers  DEM-MBD coupling  simulation optimization

摘要:

针对滚勺式精量穴播器固定成穴器成穴轨迹呈余摆线，余摆线过大造成撕膜和挑膜的问题，同时为降低株距的差异性，基于离散元法和多体动力学耦合方法对穴播器成穴器运动过程进行仿真分析。以牵引速度、牵引角度和穴播器质量为影响因素，以余摆线宽度、株距和播种深度为响应值，通过预试验和单因素试验确定各因素对响应值的影响规律，基于前期仿真试验结果开展多因素仿真试验获得最优参数组合，并通过田间试验验证最优结果的可靠性。结果表明：滚勺式精量穴播器成穴器运动的最优参数组合为，牵引速度523.43 mm/s、牵引角度21.9°、穴播器质量18.2 kg，此时株距为196.84 mm，余摆线宽度13.98 mm。以最优参数组合进行验证试验，株距为193.86 mm，相对误差1.51%；余摆线宽度13.28 mm，其相对误差4.39%。

Abstract:

Aiming at the problems that the trajectory of fixed cavity formers of rolling spoon-type precision cavity seeders is in the form of a residual pendulum line， and the residual pendulum line is too large， which causes tearing and picking of the film， and in order to reduce the variability of the spacing of the plants， the simulation and analysis of the motion process of the cavity seeders are conducted based on discrete element method and multi-body dynamics coupling method. Taking the traction speed， traction angle and cavity seeder quality as the influencing factors， and the residual pendulum width， plant spacing and sowing depth as the response values， the influence law of each factor on the response values is determined through pre-test and single-factor test. Based on the results of the pre-simulation test， a multi-factor simulation test is carried out to obtain the optimal parameter combinations and to verify the reliability of the optimal results through the field test. The results show that： The optimal parameter combination of rolling spoon-type precision cavity formers is traction speed 523.43 mm/s， traction angle 21.9° and cavity seeder mass 18.2 kg. Under above condition， the plant spacing is 196.84 mm， and the width of the residual pendulum line is 13.98 mm. The optimal parameter combinations for the validation test are the plant spacing 193.86 mm with relative error 1.51%， the residual pendulum line 13.28 mm with relative error 4.39%.