Kinematic analysis of a hopper-type dibbling mechanism for a 2.6 kW two-row pepper transplanter

Md Zafar Iqbal,Md Nafiul Islam,ALI MOHAMMOD,Md Shaha Nur Kabir,Tusan Park,강태경,Kyu-Sik Park,정선옥 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.6

In this study, suitable dimensions were determined for the major design parameters of a gear-driven hopper-type dibbling mechanism using kinematic analysis, to achieve the required planting intervals and depths. The mechanism consists of three main parts: a primary arm, two connecting arms, and two dibbling hoppers. Based on the kinematic analysis, six candidate combinations of the arm length were derived from the recommended gear contact ratios. The most favorable combination for the dibbling mechanism was a 240-mm-long primary arm, 70-mm-long connecting arms, and 153-mm-long dibbling hoppers. The power consumption for the optimized dibbling mechanism was calculated to be 28.96 W without soil interaction, and measured as 40.91 W during transplanting. The mechanism provides a planting speed of 2 seedlings per second with seedling uprightness and planting success rate of 90°±3.26° and 91.8 %, respectively. The optimized dibbling mechanism was demonstrated to quickly and accurately transplant seedlings with low power consumption, which makes it an attractive and economical option for mechanization of the pepper cultivation process.

Performance Evaluation of a Suspension-Type Dehumidifier with a Heating Module for Smart Greenhouses

Md Nafiul Islam,Md Zafar Iqbal,ALI MOHAMMOD,장보은,Milon Chowdhury,Md Shaha Nur Kabir,장승호,정선옥 한국농업기계학회 2020 바이오시스템공학 Vol.45 No.3

Purpose The management of the temperature and humidity inside greenhouses is essential for optimum crop growth. The temperature and humidity statuses extensively depend on the performance of dehumidifiers and heaters in the greenhouses. The objective of this study was to evaluate the performance of a small-scale suspension-type dehumidifier with a heating module in terms of temperature and humidity changes over time, and monitoring and controlling the status of individual actuating components in summer and winter. Methods The prototype consisted of a dehumidifier, a fan, and a heating module. Twenty-seven temperature and humidity sensor nodes were placed in three layers (top, middle, and bottom) and in three sections (front, center, and rear sides) for monitoring the temperature and humidity statuses. Two additional temperature and humidity sensor nodes were placed in front of the module and outside the greenhouses. An on/off controller was used to manage the temperature and humidity during the operation of the dehumidifier. Results Remote monitoring and controlling was successfully achieved to operate the dehumidifier with a heating module without interruption during the experiments. The time response and change results confirmed the satisfactory performance of the on/off control. The power consumption values varied depending on the status of the actuators. When the dehumidifier, fan, and heater were turned on, the average power consumption values were 556.64 ± 1.94, 125.80 ± 1.26, and 3779.60 ± 2.24 W, respectively. The temperature and humidity showed a considerable amount of spatial and vertical variability, and the temperature and humidity changes were greater in the middle section than in the other sections in both the summer and winter greenhouses. Conclusion The outcomes of the research support the need for small-scale suspension-type dehumidifiers for region-specific temperature and humidity management, and may inform possible improvement of the prototype.

Theoretical Overturning Analysis of a 2.6-kW Two-Row Walking-Type Automatic Pepper Transplanter

IQBAL MD ZAFAR,Islam Md Nafiul,ALI MOHAMMOD,Kiraga Shafik,김용주,정선옥 한국농업기계학회 2022 바이오시스템공학 Vol.47 No.1

Purpose Overturning on uneven and sloped surfaces is an important issue during the operation of agricultural field machinery. In this study, the geometrical (size and location) parameters of a pepper transplanter under development were optimized by theoretical overturning analysis to maintain stability during the operation. Methods A walking-type transplanter was designed to transplant pepper seedlings in a two-row cultivation pattern so that the transplanting could be completed using three primary mechanisms for seeding, i.e., supply, picking, and dibbling. The four-wheel transplanter was designed to work with three different forward speeds (i.e., 0.3m/s, 0.65 m/s, and 1.3 m/s). Mathematical and 3-D models were constructed both for static and dynamic conditions, and simulation was performed using a commercial software package to minimize the overturning tendency of the transplanter. Results Considering the plant ridge height and width, the track width and wheelbase of the transplanter were determined to be 725mmand 680mm, respectively. The positions of the mechanisms were optimized to maintain the center of gravity (CG) of the transplanter in the middle point of the stability area with a 436.26 mm height from the ground. During the static analysis, the transplanter was overturned laterally and longitudinally at slope angles of 40.67° and 36.26°, respectively. The transplanter overturned when the angles exceeded 29.3° for uphill and 49° for downhill paths, respectively, at the maximum forward speed (1.3 m/s) during dynamic analysis. Also, lateral overturning occurred while one wheel was exposed to obstacles with heights greater than 245 mm at the maximum operating speed. Conclusions The results of this study would be helpful for designing the layout of the transplanter and the field test of the prototype.

Variability Analysis of Relative Humidity during Operation of a Dehumidifier in a Closed Chamber and a Small Plastic Greenhouse

( Md. Nafiul Islam ),( Md. Zafar Iqbal ),( Bo-eun Jang ),( Md. Shaha Nur Kabir ),( Hyeon-tae Kim ),( Sun-ok Chung ) 한국농업기계학회 2019 한국농업기계학회 학술발표논문집 Vol.24 No.1

Analysis of humidity variations inside the greenhouse is important for optimum growth and controlling the diseases and physiological disorders of plant. The objective of this study was to analyze the vertical and spatial variability of humidity inside a closed chamber and a small plastic greenhouse to evaluate the performance of a dehumidifier. In this study, a 4-kW dehumidifier was used for dehumidification in a closed chamber (5.7m×2.9m×2.5m) and a plastic small greenhouse (7m×5m×3m). In this experiment, the dehumidification range was from 90% to 70% and 80% to 70% with three replications. Before the dehumidification experiment, the humidity of the chamber and greenhouse was increased using the additional humidifier and then mixed the humidity well by using an air mixer. Each experiment was started after the chamber humidity level goes in a stable condition. A total twenty-seven (27) temperature and humidity sensor nodes were uniformly placed at three sections such as front, middle, and rear parts of the greenhouse, placing three (3) sensors in the top, middle, and bottom positions at each section. Additional two temperature and humidity sensor nodes were placed in front of the heater and outside of the greenhouse. Sensor nodes were composed of Arduino UNO micro-controller and nRF24L01 2.4 GHz radio/wireless transceivers modules were used for communication. The operational time for average dehumidification was recorded as 70 min and 30 min for 90% to 70% and 80% to 70% humidity range respectively for the closed chamber experiment. In the plastic small greenhouse, the operational time for average dehumidification was recorded as 30 min and 15 min for 90% to 70% and 80% to 70% humidity range respectively. Results of this study showed the vertical and spatial variability of humidity inside the experimented chamber and greenhouse. Further study would be necessary for the development of a control algorithm of the dehumidifier with a heating module in various greenhouses.

Performance Evaluation of Trenchless Subsurface Drainage Piping Machine

Md Nafiul Islam,Md Zafar Iqbal,Md. Shaha Nur Kabir,정기열,문동해,정선옥 한국농업기계학회 2019 바이오시스템공학 Vol.44 No.4

Purpose Subsurface pipe drainage can ensure consistent and profitable crop production in poorly drained agricultural regions to remove excess water from the agriculture field. However, improvement is needed in the drainage pipe installation method for the stable production of field crops. The objective of this research was to conduct a performance evaluation of a trenchless subsurface drainage piping machine in terms of pulling force requirement and pipe laying depth uniformity to facilitate the maintenance of soil water control with minimum labor. Methods Two experiment fields were selected considering the physical properties of soil, i.e., silty loam and silty clay loam fields. A load cell and a distance-measuring sensor were used to measure the pulling force and pipe burial depth uniformity, respectively, at two operation depths (40 cm and 45 cm) in both fields. The soil properties (bulk density, cone index, porosity, and soil water content) were measured at various depths (up to 55 cm) from the soil surface. Results The average pulling forces were found to be 6.78 ± 1.35 kN and 7.36 ± 1.55 kN at a depth of 40 cm and 10.07 ± 1.17 kN and 15.49 ± 1.09 kN at a depth of 45 cm for silty loam field and silty clay loam field, respectively. The average laying depths at the laying depth of 40 cm were 40.07 ± 0.30 cm and 40.34 ± 0.33 cm and those at the laying depth of 45 cm were 45.5 ± 0.22 cm and 45.24 ± 0.22 cm for silty loam field and silty clay loam field, respectively. The laying depth condition of 45 cm showed relatively better uniformity than the condition of 40 cm. Conclusions The outcomes of the research can provide a useful reference for the subsurface pipe installation guidelines of a trenchless subsurface drainage piping machine for the pipe drainage network.

Evaluation of pepper seedling growth according to the growing period and tray for automatic transplanting

Nafiul Islam,Md Zafar Iqbal,ALI MOHAMMOD,이예슬,우재근,최일수,정선옥 충남대학교 농업과학연구소 2021 Korean Journal of Agricultural Science Vol.48 No.4

The effective growth of pepper seedlings relies on the growing period and tray used, which both aim to minimize seedling damage during the transplantation process. Therefore, the objective of this study was to evaluate the effect of red and green pepper seedling growth in plug and cylindrical paper pot (CPP) trays with different growth periods of the seedlings. Two different seedling growth trays were used for the two varieties of pepper seedlings in the same growing media. The pepper seedling growth rates were investigated at 15, 30, and 45 days for each of variety. Important parameters, e.g., the plant height, fresh weight for the plant and root, number of leaves, leaf length and width, and leaf chlorophyll contents, were measured. During the experiment, the CPP tray maintained uniform seedling growth as compared to the plug tray. CPP trays ensured the height of the seedling, with these results 0.84 to 1.6 times higher than those of the plug tray for all conditions, indicating the good quality of the pepper seedlings. The shoot and root weights were found to be greater with more leaves in the CPP tray seedlings for 45 days compared to the seedlings grown in the plug tray, whereas the green pepper variety showed a greater leaf ratio than the red pepper seedlings. The analysis of pepper seedling growth presented in this study will guide the selection of suitable growth trays and seedling periods for farmers when they undertake automatic pepper transplantation in the field.