In Huang-Huai-Hai plain of China, farmers collect the maize straw for livestock during maize harvest to increase their revenue. To maintain the sustainable productivity of the soil, all straw after the wheat harvest is returned to the field. This straw brings difficulties in the no-till seeding for maize after wheat harvest, and thus it is necessary to develop efficient no-till seeders that can cope with heavy residue and improve sowing quality. In this work, we designed a wide-strip-till no-till pneumatic maize (WNPM) seeder to satisfy the need in this plain. The key parameters of the opposite-placed anti-blocking mechanism of the WNPM seeder were determined via the discrete element method (DEM) technology, while the parameters of the pneumatic maize seed meter were specified using the coupled simulation of computational fluid dynamics (CFD) and DEM. We also carried out field experiment to test the performance of our machine. Under the operating speed of 8 km/h, the soil disturbance was 38.2%. Moreover, the straw cleaning rate achieved 94.4% in the seeding belt while the residue cover index of the seed plot was over 58%, and the seeding performance was improved significantly. The qualified seed spacing index, uniformity variation coefficient, qualified index of sowing depth and variation coefficient of sowing depth were 96.6%, 19.1%, 95.1% and 3.2%, respectively. In general, the WNPM seeder improves the working efficiency of maize sowing because both the reliable working speed and the sowing quality were increased. These results are of considerable importance for crop production in Huang-Huai-Hai plain of China.

During the sowing operation, the consistency and stability of the row dispenses of a seeder are important indicators for evaluating sowing performance. A multi-channel real-time weighing device was designed to study and analyze the consistency of row dispenses in seeder under identical conditions, as well as the stability of dispenses from a seed dispenser. This device utilized two Arduino boards as controllers for data acquisition, processing, and transmission. Based on the Serial Peripheral Interface (SPI), data exchange between multiple Arduinos was achieved in a master-slave configuration, allowing for data acquisition from 14 pressure sensors in a one-master, one-slave setup. Pressure data was collected using pressure sensors, HX711 converter chips, and Arduino. LabVIEW was utilized as the upper computer to read data from the Arduino host serial port and provide real-time display and storage. This paper presents the structural and working principles of the device. Experimental tests on the weighing unit were conducted using a test bench to evaluate measurement errors. The absolute error mean ranged from 0.143 g to 0.262 g. Additionally, the impact of the seed impact force on the error was simulated using EDEM. The device was used to evaluate a six-row wheat seeder under the experimental conditions of the groove wheel having a length of 2.5 cm and a groove wheel speed of 25 r/min. The maximum coefficient of variation for seeding stability (Y1) was 2.38%, the minimum was 0.83%, and the mean was 1.21%. The coefficient of variation for consistency of seeding in rows (Y2) was 1.86%.

Vehicle-induced soil compaction occurs when agricultural machinery is working in the fields. The accumulated soil compaction could destroy soil structure and inhibit crop growth. The low degree of visualization of soil compaction has always been an important reason for restricting the development of compaction alleviation technology. Therefore, the main objective of this study was to predict soil compaction based on soil and agricultural implement parameters. The component of soil compaction prediction includes traffic-induced stress transmission evaluation and the quantitative relationship between soil stress and bulk density. The modified FRIDA model was used to elucidate the soil stress propagation, which has been validated by previous studies. The Bailey formula was used to establish the intrinsic relationship between soil stress and bulk density. The soil uniaxial compression test was applied to obtain the parameters of the Bailey formula, and soil samples were prepared with three different levels of water content. After fitting with the Bailey formula, under the condition that the soil moisture contents were 16%, 20%, and 24%, the fitting coefficients of soil bulk density were respectively 0.980, 0.959, and 0.975, which were close to 1. The results indicated that the Bailey formula could be used to calculate soil bulk density based on the stress conditions of the soil. To verify the practicality of the soil compaction prediction model, a field experiment was carried out in Zhuozhou City, Hebei Province, China. The treatment was set for 1, 3, 5, 7, and 9 times compaction with two different loads of compaction equipment. The results showed that the fit coefficient between the predicted and measured values of soil bulk density was greater than 0.641. The slope of the equation was greater than 0.782, proving that the soil bulk density prediction model based on agricultural implements and soil parameters has a good predictive effect on soil bulk density. The soil compaction evaluation model can provide a theoretical basis to further understand the soil compaction mechanism, allowing rational measures of soil compaction alleviation to be made. Keywords: soil traffic-induced compaction, agricultural implement, soil bulk density, no-tillage, soil structure, quantification DOI: 10.25165/j.ijabe.20201305.5480 Citation: Wang X L, Zhang X C, Lin X N, Sha L M, Yang H Y, Guo Z Y, et al. Quantification of traffic-induced compaction based on soil and agricultural implement parameters. Int J Agric & Biol Eng, 2020; 13(5): 134–140.

In traditional scallion cultivation, the bare-root transplanting method—which involves direct seeding, seedling raising in the field, and lifting—is commonly adopted to minimize seedling production costs. However, during the mechanized transplanting of bare-root scallion seedlings, practical problems such as severe seedling damage and poor planting uprightness exist. In this paper, the Hertz–Mindlin with Bonding contact model was used to establish the scallion seedling model. Combined with the Plackett–Burman experiment, steepest ascent experiment, and Box–Behnken experiment, the bonding parameters of scallion seedlings were calibrated. Furthermore, the accuracy of the scallion seedling model parameters was verified through the stress–strain characteristics observed during the actual loading and compression process of the scallion seedlings. The results indicate that the scallion seedling normal/tangential contact stiffness, scallion seedling normal/tangential ultimate stress, and scallion Poisson’s ratio significantly influence the mechanical properties of scallion seedlings. Through optimization experiments, the optimal combination of the above parameters was determined to be 4.84 × 10⁹ N/m, 5.64 × 10⁷ Pa, and 0.38. In this paper, the flexible planting components of scallion seedlings were taken as the research object. Flexible protrusions were added to the planting disc to reduce the damage rate of scallion seedlings, and an EDEM-ADAMS coupling interaction model between the planting components and scallion seedlings was established. Based on this model, optimization and verification were carried out on the key components of the planting components. Orthogonal experiments were conducted with the contact area between scallion seedlings and the disc, rotational speed of the flexible disc, furrow depth, and clamping force on scallion seedlings as experimental factors, and with the uprightness and damage status of scallion seedlings as evaluation criteria. The experimental results showed that when the contact area between scallion seedlings and the disc was 255 mm², the angular velocity was 0.278 rad/s, and the furrow depth was 102.15 mm, the performance of the scallion planting mechanism was optimal. At this point, the uprightness of the scallion seedlings was 94.80% and the damage rate was 3%. Field experiments were carried out based on the above parameters. The results indicated that the average uprightness of transplanted scallion seedlings was 93.86% and the damage rate was 2.76%, with an error of less than 2% compared with the simulation prediction values. Therefore, the parameter model constructed in this paper is reliable and effective, and the designed and improved transplanting mechanism can realize the upright and low-damage planting of scallion seedlings, providing a reference for the low-damage and high-uprightness transplanting operation of scallions.