Sensor-Based Nutrient Recirculation for Aeroponic Lettuce Cultivation

Chowdhury Milon,ISLAM MD NAFIUL,Reza Md Nasim,ALI MOHAMMOD,Rasool Kamal,Kiraga Shafik,이대현,정선옥 한국농업기계학회 2021 바이오시스템공학 Vol.46 No.1

Purpose The objective of this study was to investigate the effects of used-nutrient solution recirculation on nutrient efficiency improvement and reduction of environmental pollution of an ion-selective electrodes (ISEs)-based recycle-type aeroponic crop cultivation system. Methods A recycle-type aeroponic crop cultivation test bench was fabricated, which consisted of K+, NO3-, and Ca2+ ISEs, pH, and EC sensor, and lettuce were cultivated for inspecting the nutrient solution recirculation process. The specific growth rate of lettuce was evaluated. Different percentages of the used-solution (20%, 40%, 60%, 80%, and 100% of the target volume) were recirculated to find a proper recirculation volume for maintaining the target nutrient level with the minimum supply of stock solutions. The nutrient saving percentage was determined by comparing the nutrient solution requirement with the open-type aeroponic system and open-field cultivation practices. Reduction of environmental pollution was assessed based on the possible environmental pollutions (i.e., surface water pollution, groundwater contamination, and contaminant deposition in the human body), which could be occurred by the direct discharge of the hydroponic nutrient solution. Results The minimum amount of stock solutions were required during the 60%used-solution recirculation. The nutrient solution requirement of the recycle-type aeroponic system was almost 3 to 5 times less than the open-type aeroponic system, and 3 to 6 times less than open-field cultivation based on nutrient consumption rates at different growth stages. An open-type aeroponic system might require more nutrient solution than the open-field cultivation practices based on the frequency of nutrient solution supply in the crop root zone. Although, the discharged nutrient solution increased the K+, NO3-, andCa2+ ion levels a little in the considered surface water reservoir, groundwater, and human body, long-term discharge of the high concentrated hydroponic nutrient solution would be hazardous. Conclusion The findings of this study showed that the nutrient saving efficiency of a recycle-type crop cultivation system is higher compared to the open-type and conventional cultivation practices, which can minimize the cultivation cost notably, and the environmental pollutions can be reduced significantly through the sensor-based nutrient management.

Pump, Pipe, and Tank Sizes for Effective and Adequate Nutrient Solution Supply of Hydroponic Crop Production Systems

( Milon Chowdhury ),( Won-jae Lee ),( Young-woo Seo ),( Ye-seul Lee ),( Shaha Nur Kabir ),( Sun-ok Chung ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In the study, proper pump, pipe, and tank size were identified based on plant numbers through simulation for effective and adequate nutrients supply to the plant’s root zone of a hydroponic crop production system. Some sizing methods were proposed and applied to a small scale aeroponics system for the demonstration. For 192 cabbage plants, an 8 lpm and 1600 KPa capacitated pump, ¾ inch dia. pipe and 50 L sized tank was considered for that system. A simulation was carried out to show the changes of pump, pipe and tank size with plant numbers. It has been found that 0~200 and 200~1000 plants could be irrigated using a single pump by adjusting pressure head and flow rate, through ½ ~ ¾ inch diameter pipe. But irrigating higher number of plants by a single pump drops pressure due to pipe losses. Tank size showed a proportional relationship with plant bed cum plant number. 15~250 L tank was required for considered plant range. Further study for verifying this simulation result would be required under various crop and growing conditions.

Basic Tests of Automatic Nutrient Monitoring for Hydroponic Crop Production System

( Milon Chowdhury ),( Won-jae Lee ),( Young-woo Seo ),( Sun-ok Chung ) 한국농업기계학회 2017 한국농업기계학회 학술발표논문집 Vol.22 No.2

Nutrients monitoring and control system plays a vital role in plant growth of hydroponic crop production system in plant factory. Usually, it is done by checking EC and pH, but it has several limitations. An automated ion based nutrient control system was developed to control optimum nutrients level using Ion-Selective Electrodes array. The nutrient management system was divided into two major segment - sensing part and control part. The sensing issues namely Measurement error (%), Signal drift, Calibration, Data acquisition interval and Solution temperature have been focused here. NI-USB 6009, Ca, NO3 and K Ion Selective Electrodes were used to investigate the issues. The whole system was coded using LabVIEW (2017) and the correlated components were measured in standard and real-time nutrient solution. The K, NO3 and Ca ISEs were tested in 10, 100, 1000 ppm standard solution and measurement errors (%) were found ±25.23%, ±8.09%, and ±28.51%, respectively. In the case of signal drift, K, NO3 and Ca ISE showed a continuous upward, downward and downward signal trend, respectively. The regression value of calibration were 0.99, 1 and 0.99 for K, NO3 and Ca sensors, respectively. All sensors showed the best response in 0.01 sec data acquisition time interval and 20~25C solution temperature. Most of the errors occurred due to signal drift and bio-film formation in the sensors head. Continuous rinsing, proper calibration, and maintaining of appropriate solution temperature could help to get accurate readings. In the summary, An ISE-based nutrient monitoring system would be a viable technique for improving accuracy and precision application of nutrient solution in the plant factory crop production system.

Fault Detection of Sensors and Actuators for Monitoring and Control of Ambient Environment in Protected Crop Cultivation Facilities

( Milon Chowdhury ),( Sandah Wing ),( Md. Shaha Nur Kabir ),( Kyu-dong Na ),( Soo-bok Park ),( Sun-ok Chung ) 한국농업기계학회 2019 한국농업기계학회 학술발표논문집 Vol.24 No.1

Monitoring and controlling of ambient environment plays an important role for quality production in protected crop cultivation facilities. However, malfunctioning of sensors and actuators used for monitoring and control of the ambient environment could interrupt the robustness of the management system. In this research, the malfunctioning of sensors and actuators was detected based on the interaction matrix technique and current consumption rate to increase the effectiveness and ease of protected crop cultivation management. A small-scale smart greenhouse consisted sensors (temperature, humidity, CO2, Light/solar radiation, wind speed and direction, soil water content, current sensors) and actuators (heater, cooler, humidifier, dehumidifier, fan, CO2 controlling device, light source, and water supply unit, window control motor) were used for testing and detecting the malfunctioning of the monitoring and control system. A controlling system consisted of a micro-controller, relays, and a LabVIEW coded program. Functioning status of all sensors and actuators was checked by the current sensor. An interaction matrix-based algorithm was developed for malfunctioning detection. Four fault scenarios such as abrupt, incipient, intermittent, and simultaneous faults were considered in the sensors and actuators. This method was capable to detect 90% of the artificial failure in short computational time, which proved its suitability for real-time applications. This accurate and efficient fault detection technique can be used to improve safety and reliability, especially when the cultivated crops are more valuable and environmentally sensitive.

수경 작물 재배 시스템의 양액 조제에 영향을 미치는 요인 식별

밀론초두리 ( Milon Chowdhury ),카말라술 ( Kamal Rasool ),모하마드알리 ( Mohammod Ali ),나딘알리칸 ( Nadeen Ali Khan ),정선옥 ( Sun-ok Chung ) 한국농업기계학회 2020 한국농업기계학회 학술발표논문집 Vol.25 No.1

Automatic target hydroponic solution preparation is still a critical issue as several factors affect this process. The objective of this study was to identify the major factors affecting the target nutrient solution preparation, in terms of nutrient mixing method, coefficients identification, and stock solutions supply rate, for hydroponic crop cultivation. A hydroponic nutrient solution preparation test bench was fabricated, which consisted of sensors, tanks, pumps, pipes, and a controller. Two control methods, on/off and PID, were implemented and coefficients of the relevant control methods, dead-band for the on/off, and Kp, Ki, Kd for the PID method, were identified through mathematical simulations. Validation tests were performed to select the suitable control method along with their coefficients based on the response time and steady-state error. Effects of different stock solution supply rates (0.03, 0.05, and 0.1 Lmin-1) on the control methods were also evaluated. In the on/off and PID control method, the target ion concentration was maintained with the errors of 22.15% and -1.241%, respectively. Considering 2% dead-band for on/off method, and tuning the PID coefficient, the steady-state error reduced to 1.175% and -0.398%, respectively. In the case of on/off control, duration of oscillation and overshoot volume were increased with stock solutions supply rate. In the PID control, the low supply rate (0.03 Lmin-1) showed the minimum steady-state error (-0.402%), but took a long time to reach steady (364s). The Rising time for the high supply rate (0.1 Lmin-1) was short (89s), but the steady-state error was high (-1.363%). The results indicate that the nutrient mixing method, relevant coefficient/s identification, and supply rate of the stock solutions need to be adjusted system-specifically.

Working speed analysis of a gear-driven rotary planting mechanism of a 12-kW self-propelled riding-type automatic onion transplanter

초두리밀론 ( Milon Chowdhury ),레자나심 ( Nasim Reza ),알리모하마드 ( Mohammod Ali ),고란닺앗라퐂자만 ( Ashrafuzzaman Gulandaz ),권행주 ( Haing-ju Kwon ),정선옥 ( Sun-ok Chung ) 한국농업기계학회 2021 한국농업기계학회 학술발표논문집 Vol.26 No.2

The development of a riding-type automatic onion transplanter could be effective in improving the mechanization rate in onion cultivation, where the working speed analysis plays a vital role and determines planting performance and efficiency. The objective of this study was to select a suitable working speed of a 12 kW self-propelled riding-type automatic onion transplanter for efficient planting of onion seedlings with minimum damage. The proposed transplanting mechanism consisted of six assembling units of picking, conveyors, and rotary planting mechanism, where every rotary planting unit needs a continuous supply of onion seedlings at a certain rate for uniform and upright plantation. To enable the smooth collection and plantation of onion seedlings, analysis was carried out via a mathematical working trajectory model of the planting mechanism, virtual prototype simulation, and validation tests using a physical test bench. In the mathematical model analysis and simulation, the suitable rotational speed was found as 60 rpm and it was able to transplant 60 and 120 seedlings/min using the single and double unit assembly of planting mechanism, respectively. A 130 mm/s forward speed of the transplanter was preferable in terms of seedling uprightness and low damage. A forward speed of 130 mm/s with a transplanting speed of 120 seedlings/min was preferable in terms of achieving a high degree of seedling uprightness. A field test using the real prototype of the onion transplanter would be necessary to verify the accuracy of these findings.

Basic performance test for sound detection and remote monitoring in Pig Farm

레자나심 ( Nasim Reza ),초두리밀론 ( Milon Chowdhury ),키라가샤피크 ( Shafik Kiraga ),정선옥 ( Sun-ok Chung ) 한국농업기계학회 2021 한국농업기계학회 학술발표논문집 Vol.26 No.2

Precision livestock farming is an intelligent technology, which allows the closer monitoring of each animal on farms. Sound based precision farming provides considerable benefits compared to other technology, such as imaging sensor, motion sensors, etc. In addition, sound sensors are inexpensive, no direct contact, and a huge number of animal can be observed using a single sensor. The objective of this study was to investigate a remotely monitored sound detection and imaging system in pig farm for early detection of respiratory diseases. Three microphones and three RGB cameras with three micro-controller were used to receive the sound and image data in the pig farm. Total 30 pigs were covered by our surveillance system. A sound analysis algorithm was developed to record the sounds received by the microphones and distinguished the pig sounds from the outside noises. The sound was then processed by the algorithm to detect the abnormal sound of pigs. The images were synchronized and used to monitor the unwanted movement and behaviour. High, medium, and low frequency sounds were detected. The results showed that the detection efficiency for high frequency sound was around 85%, and for low frequency sound was 73%. Moreover, movement of pigs were also monitored by images. From this study, it would be feasible to recognize early respiratory illness in pigs through automated and sequential monitoring of sounds and images within the pig farm.

Analysis of Driving Stability and Vibration of a 20-kW Self-Propelled 1-Row Chinese Cabbage Harvester

ALI MOHAMMOD,이예슬,Chowdhury Milon,KHAN NADEEM ALI,Swe Khine Myat,Rasool Kamal,Kabir Md Shaha Nur,이대현,정선옥 한국농업기계학회 2021 바이오시스템공학 Vol.46 No.1

Purpose Overturning and high vibration levels are major causes of agricultural farm fatalities and mechanical troubles during operation. This study assessed the stability angles of a self-propelled 1-row Chinese cabbage harvester and measured the vibration levels for safety under different conditions. Methods The stability of the Chinese cabbage harvester was investigated using computational methods, and the vibration levels were measured on off-road and field conditions. The three-dimensional model of the Chinese cabbage harvester was designed and simulated to evaluate the static stability angles employing commercial software. The relationship between vehicle and deformable soil was calculated using the empirical models. The critical angles and the climbing ability of the developed harvester were examined under loaded and unloaded conditions. The vibration exposures were measured on the cabbage conveyor and the power transmission part in static, off-road, and field operation conditions under various speeds and slopes. Results The stability simulation results showed the minimum lateral stability angles of the harvester were pointed on the loaded condition compared to the unloaded condition. The maximum sideways overturning angle of the Chinese cabbage harvester was recorded as 32° at 150° ground angle and 30° at 270° ground angle, from the moving directions clockwise, for unloaded and loaded conditions. The high levels of vibration were measured at 0.19, 1.64, and 1.38 m/s2 for static, off-road, and field conditions at high speeds among X-, Y-, and Z-axis directions, respectively. Besides, the considerable vector sum (Av) exposures were calculated 1.54, 2.14, and 2.48 m/s2 at 0.3, 0.6, and 0.9 m/s forward speeds on the cabbage conveyor part. Conclusion The concept and guidelines of this research could help to protect operators from safety risks and expose vibration characteristics during farm operations of the self-propelled Chinese cabbage harvester prototype.

IoT를 이용한 사막 토양에서의 벼 재배를 위한 센서 기반 자동관개제어 시스템

모하마드알리 ( Mohammod Ali ),카말라술 ( Kamal Rasool ),밀론초두리 ( Milon Chowdhury ),정재혁 ( Jae-hyeok Jeong ),정선옥 ( Sun-ok Chung ) 한국농업기계학회 2020 한국농업기계학회 학술발표논문집 Vol.25 No.1

Automatic irrigation according to the water demand is an efficient way to manage the water loss and ensure the rice quality and productivity in desert soil. Therefore, the aim of the study was to develop a sensor-based automatic irrigation control system for rice production in desert soil using Internet of Things (IoT). Field experiment was conducted in tropical desert area located at United Arab Emirates University (UAEU) farm site at Al-Foah, Al-Ain, UAE. A Linux based VPS system on Raspberry Pi 3 model B+ platform was used to implement the irrigation control unit. Python programming language was used for automation purpose. Commercial soil water content sensor (ECH20 EC-5) and relays were interfaced with the raspberry GPIO pins which were responsible to switch motor on/off. The water content percentage (%) ranging from 25~30% were considered for the rice growth in the desert soil. The output value of the water content sensors were posted and stored on the dedicated web server. The irrigation system operated based on the developed algorithm which autonomously maintain the required soil water content level in the dessert soil depending on their out put values. The pump were observed to be in operation when soil water content level dropped down below the 25% and vice versa. The proposed study based on IoT helped to display the current water content (%) and the status of pump operation (on/off). The smart irrigation system would be suitable to monitor the moisture content for rice cultivation in desert soil.

Theoretical Analysis of Power Requirement of a Four-Row Tractor-Mounted Chinese Cabbage Collector

Swe Khine Myat,ISLAM MD NAFIUL,Chowdhury Milon,ALI MOHAMMOD,Wing Sandah,전현종,이상희,정선옥,김대건 한국농업기계학회 2021 바이오시스템공학 Vol.46 No.2

Purpose Analysis of power requirement is the key issue to ensure the optimal design. The objectives of the study were to investigate theoretically the tractor hydraulic power and draft power requirement of a tractor-mounted Chinese cabbage collector system and to suggest design guidelines. Methods The major components of the Chinese cabbage collector under development were a belt type conveyor, a hydraulic motor, and three hydraulic cylinders. Hydraulic motor power, cylinder hydraulic power, and draft power for various speeds under unloaded and loaded conditions were calculated using theoretical equations. Different tractor configurations (44~74 kW), soil types (sand, silt, and clay), and hydraulic fluid capacity (1~5m3/hr) were considered to determine the tractor hydraulic power and engine power requirement. Results The power requirement of the hydraulic motor for the unloaded and loaded conditions was 1.14 kW and 1.24 kW, respectively, under the 120-rpm conveyer speed. Hydraulic power of 2 ×10−3 kW was required to fold or unfold the collecting conveyor. The maximum required draft power levels were 0.67, 0.81, 0.94, and 1.21 kW for the hard, firm, tilted, and soft soil conditions, respectively. Based on the results, the total maximum power requirement was calculated as 15.14 kW, of which 7.25 kW is for the hydraulic power (48%) and 7.89 kW for the draft power (52%), respectively. Conclusion The analysis of power requirements presented in this research can help estimate the tractor hydraulic power and draft power requirement to run a tractor-mounted Chinese cabbage collector efficiently.