Modelling and implementation of an MR damper into a no-till seeding assembly for optimising its dynamic performance

摘要

In no-till seeding, a proper seeding depth is a very important factor that results in reliable seed germination and seedling emergence. However, achieving a consistency in seeding depth is one of the most challenging tasks in no-till seeding, due to instability in the dynamic response of seeding machine to harsh soil conditions. The inadequate response of the seeder motion dynamics to harsh soil condition and the high driving speed are responsible for extreme variations in the desired seeding depth. Optimising the dynamics of no-till seeder for better performance is of high importance for seeding machine developers. In this paper, the reduction in the amplitudes of the profile impact force and the pitch angles, of the magnetorheological (MR) damper implemented seeding assembly by comparing its dynamics from real-life testing and the simulated ones were evaluated. The comparison of the impact forces between the simulation results and the real-life measurement revealed a difference of 3.16 N and 11% for mean-squared deviation (MSD) and mean deviation percentage (MDP), respectively. These were equal to 0.058 degrees and 13.5% for the pitch angles. The above described improvement in dynamics from the real-life testing resulted in an optimised seed placement by reducing the seeding depth variation compared to the target seeding depth.