Thai Society of Agricultural Engineering Journal

The Design and Development of GPS Navigation for Rice Direct Seeding Machine

Somporn Hongkong — 2025-12-22

This article presents testing of the movement control of an automatic rice planter equipped with a GPS control system through the Mission Planner program. The installation of a steering control system for the machine involves receiving signals from the Pixhawk board with the GPS module. To obtain the position and determine the direction for the system to process and control the motor, ensure the dropper’s steering wheel remains on the specified path. The operation test accuracy is set to 0.2, 0.3 and 0.4 m·s^-1 and 2 types of error distances are tested. This includes checking the starting-final stopping distance at 400 m and the straight-line error at 100 m, with data collected every 10 m. The test results showed that a speed of 0.2 m·s^-1 results in the least stopping distance and straight-line error. Since the vehicle’s movement is repetitive, it will keep the vehicle in the specified line as best as possible. Result from different P Control adjustments.

Performance Evaluation of a Sugarcane Leaf Stripper and Trash Incorporator for the LK92-11 Cultivar

Tinnasit Kaisinburasak — 2025-12-22

The purpose of this study was to design and develop a Sugarcane Leaf Stripper and Trash Incorporator to facilitate labor in harvesting and alleviate the effects of sugarcane burning on the sugarcane field and improve soil fertility. No equipment can simultaneously perform both processes of leaf stripping and trash incorporation. This research aimed to design equipment capable of performing both processes by applying the hydrostatic power transmission to the Sugarcane Leaf Stripper and the mechanical power transmission to the spiral-notched disc tillage unit. It was tested with the LK 92-11 sugarcane cultivar at 10 months of age in Pibulmangsahan district, Ubon Ratchathani province. The experiments were conducted in loam soil with a moisture content of 14.46% (db), 1.89 g cm^-3 dry bulk density, 1.96 MPa cone penetration resistance at two forward speeds (1.95 and 2.45 km h^-1), three gang angles (36^o, 40^o and 44^o), two disk revolution speeds (150 and 180 rpm), a constant tillage depth of 25 mm and a fixed roller speed of 800 rpm. The optimum operating parameters were evaluated using a weighted arithmetic mean method based on user satisfaction and perceived importance. These values were then used to calculate the user satisfaction index, with the highest value of 3.837, corresponding to a forward speed of 1.95 km h^-1, a gang angle of 36°, and a disc speed of 150 rpm. The experimental results showed that the machine required 10.12 kW of total power, achieved a stripping efficiency of 83.16%, a trash covering efficiency of 92.4%, and a theoretical field capacity of 2.34 rai h^-1.

Tractor-Mounted Cassava Cleaning Machine for Small Tractors

Kritsana Navarat — 2025-12-22

The objective of this research was to design and evaluate the performance of a tractor-mounted cassava cleaning machine for small tractors. The machine has dimensions of 1.20 m (width) × 1.5 m (length) × 1.6 m (height). Its structure consists of a power source, a power transmission system, and a cleaning unit. The power source is derived from the tractor's power take-off (PTO) shaft. The machine was tested at a PTO speed of 800 rpm. During operation, cassava is fed into the cleaning unit, which rotates for a specified period before discharging the cleaned material. The machine was tested at rotational speeds of 15, 20, and 25 rpm, and cleaning durations of 1 and 2 minutes. Test results showed the highest cleaning efficiency of 96.44%, achieved at 20 rpm, with a 2-minute cleaning time and a material weight of 50 kg. The highest working capacity was 5,220 kg h^-1, recorded at a cleaning time of 1 minute with a material weight of 100 kg. This cassava cleaning machine, which is mountable on a small tractor, can effectively remove impurities and scrape the outer skin.

Grain quality monitoring technologies in post-harvest storage: a review

Chukiat Chotikasatian — 2025-12-23

This review article provides an overview of the advances and developments in technologies used for monitoring the quality of cereal grains during post-harvest storage. It discusses the key risk factors that contribute to grain deterioration, including temperature and moisture content of the grains, storage insects, and fungi. Furthermore, it details modern monitoring systems that use sensor networks to measure these factors in real-time. The data obtained from such systems can be used to assess risks, helping to inform decisions on effective intervention measures to control and/or prevent problems that cause damage to the grains. This, in turn, helps to reduce losses in product quality and is also beneficial for the sustainable management of cereal grains.

Lignocellulosic Biomass Pretreatment with Spent Mushroom Substrate: An Agricultural Residue Valorization Approach for Sustainable Biogas Production

Patomporn Pulsawad — 2025-12-22

The utilization of agricultural residues for renewable energy production offers a dual benefit of reducing environmental impacts and enhancing the value of domestic biomass resources. Sugarcane leaves are an abundant lignocellulosic residue in Thailand but their recalcitrant structure, rich in cellulose, hemicellulose, and lignin, limits microbial degradation and results in low biogas yields. This study investigated the potential of spent oyster mushroom substrate (SMS) as a natural source of microorganisms and enzymes for pretreating sugarcane leaves prior to anaerobic digestion. Pretreatment was performed by mixing sugarcane leaves with SMS at a 1:1 ratio and compared with untreated leaves. The performance of residual fungal mycelia in SMS was further evaluated against newly prepared pure inocula under both sterile and non-sterile conditions. Lignocellulosic composition, reducing sugars, and chemical oxygen demand (COD) were analyzed, and methane potential was assessed using anaerobic sludge from a wastewater treatment plant. Results revealed that SMS pretreatment significantly enhanced biogas production, with higher methane yield at 26.6±5.8 L kg^-1 VS, faster digestion onset, and improved organic matter conversion efficiency compare to sole sugarcane leaf at 3.3±3.4 L kg^-1VS. Remarkably, SMS achieved methane productivity comparable to pure inoculum at 29.0±5.5 L kg^-1 VS and retained efficiency under natural microbial contamination, while pure inoculum showed reduced performance in non-sterile conditions at 9.2±2.7 L kg^-1 VS. These findings demonstrate that SMS can serve as an effective, low-cost pretreatment agent for lignocellulosic biomass, particularly sugarcane leaves, thereby enhancing methane production while simultaneously contributing to sustainable waste management. The approach supports circular bioeconomy principles and offers a scalable solution for improving energy security at community and industrial levels.

Development of a Portable Automated Detector of Soil Nitrate for Mapping Using Nitrate Ion-Selective Electrodes

Prasat Sangphanta — 2025-12-22

Management of plant nutrients to suit soil conditions in each specific sub-area of a plot (Site-Specific Management, SSM) is crucial for efficient crop production. Excessive fertilizer application not only increases production costs for farmers but also leads to soil degradation and contamination of groundwater sources. Soil analysis using sensors is suitable for analyzing a large number of soil samples due to its low cost, quick operation, and applicability in agricultural fields. The main objective of this research is to develop a tool for measuring nitrate concentration in soil using a Nitrate Ion-Selective Electrode (Nitrate-ISE) along with a GPS system for automatic data recording on a secure digital card (SD card). The system is controlled by an Embedded Board (Arduino mega 2560) and consists of five main operations: 1. Soil extraction, 2. Measurement, 3. Cleaning, 4. Satellite coordinate detection, and 5. Controller and data logger. The analysis requires approximately 0.5 liters of clean water, and the time for each sample is around 5 minutes. The optimal soil-water ratio is 1:10, and the measurement time is 30 seconds. The average accuracy of the measurements is more than 80%, with an R² = 0.80 and RMSE = 1.44 compared to laboratory methods. This prototype reduces soil analysis costs by 5-6 times, providing reliable data for creating soil maps. This information can be used to support farmers in making decisions for nitrogen fertilizer management in subsequent crop cultivation.