https://msr.bkstm.org/index.php/msr <p><strong>Mechanical Science Reports </strong>is an open access journal published by Badan Kerjasama Teknik Mesin (BKSTM) Indonesia and is engaged in the scope of energy conversion such as new renewable energy, emissions and combustion, fuels and lubricants, mass and heat transfer, thermal and fluid engineering, energy computing, power plant engineering, nano and pico energy, energy materials, energy storage and devices, and other things about energy conversion.</p> Badan Kerjasama Teknik Mesin (BKSTM) Indonesia en-US Mechanical Science Reports https://msr.bkstm.org/index.php/msr/article/view/17 <p><em>The application of appropriate planting technologies is crucial for improving smallholder agricultural productivity in tropical regions. The seed planting process affects crop yield, efficiency, and resource use. This study compares the performance of the traditional tugal planting method and the push-type planter to evaluate their suitability under tropical field conditions. This study conducted a comparative assessment focusing on four key parameters: labour efficiency, seed placement precision, soil adaptability, and economic feasibility. Data were collected through direct observation of plating rate, uniformity of seed spacing, adaptability across varying soil conditions, and the expense to smallholder farmers. The tugal method demonstrated advantages in terms of low cost, simplicity, and adaptability to diverse terrains. However, it was less efficient due to poor seed spacing uniformity and high labour requirements. Conversely, the push-type planter improves planting speed, seed distribution accuracy, and long-term labour savings. The weaknesses included the heavier weight, reduced effectiveness in uneven soils, and higher initial investment costs. The findings suggest that tugal is practical in resource-constrained environments, while push-type planters enhance efficiency and precision. The balance of technological benefits with socio-economic realities is crucial for guiding smallholder farmers in applying the appropriate planting technology in tropical agricultural systems.</em></p> Johan Kim Elloh Nia Michelle Angella Alfred Juliant Susanto Kushendarsyah Saptaji Copyright (c) 2025 Mechanical Science Reports 2025-10-06 2025-10-06 3 1 1 10 https://msr.bkstm.org/index.php/msr/article/view/20 <p><em>Motors and pumps are the crucial components for various industrial production processes such as manufacturing, oil and gas, and chemical processing. However, one common issue affecting their reliability and efficiency is shaft misalignment. Research indicates that 30–40% of major financial losses in industrial operations are caused by misalignment, while 42–50% of motor failures are due to bearing damage. It is caused by poor alignment, insufficient lubrication, or improper installation. This study focuses on evaluating the effect of shaft alignment on vibration levels and motor power consumption in a cooling water pump at the Koto Panjang Hydroelectric Power Plant. A quantitative experimental approach was applied to measure and compare equipment performance before and after alignment. Results show that alignment reduces the highest axial vibration velocity by 8.35 mm/s and vertical vibration by 1 mm/s. Furthermore, motor power consumption decreases by 8.35%, as demonstrated by a reduction in average motor current from 76.8 A to 71.2 A. The vibration pattern confirms the angular misalignment as the dominant factor contributing to instability. These findings show the importance of routine shaft alignment, not only for minimizing vibration and extending equipment lifespan but also for enhancing energy efficiency and reducing operational costs.</em></p> Dimas Yudha Satria Utama Moh. Arif Batutah Suhariyanto Copyright (c) 2025 Mechanical Science Reports 2025-10-06 2025-10-06 3 1 11 22 https://msr.bkstm.org/index.php/msr/article/view/19 <p><em>This study presents the development of a low-cost, portable bending test machine specifically designed to evaluate the mechanical properties of wood and bamboo, with a focus on providing an accessible solution for small-scale users and researchers. The machine employs a standard three-point bending configuration, equipped with digital sensors to capture accurate load and deflection data. Meanwhile, an automated grading algorithm facilitates objective assessment. The prototype was modelled in SOLIDWORKS for precision in design and subsequently fabricated using a combination of wood and 3D-printed Polylactic acid (PLA) components to ensure affordability and portability. A Raspberry Pi microcontroller was integrated to enable real-time data acquisition and processing, enhancing usability in both laboratory and field settings. Through optimized linear regression supported by Singular Value Decomposition (SVD), the system calculates effective critical mechanical properties such as Young’s modulus with a high degree of accuracy. This innovation provides a practical, efficient, and user-friendly alternative to conventional testing equipment, offering significant potential for material classification, quality control, and advancing sustainable construction practices by promoting the use of renewable resources like wood and bamboo.</em></p> Jonathan Bryan Raditya Edra Raja Handika Jarvis Eros Lananggalih Michael Harlen Sean Nabill Van Der Heijden Farid Triawan Kushendarsyah Saptaji Ignatius Budi Sutanto Hadisujoto Copyright (c) 2025 Mechanical Science Reports 2025-10-06 2025-10-06 3 1 23 40 https://msr.bkstm.org/index.php/msr/article/view/22 <p><em>Pressmud, a by-product of the sugar industry, contains significant amounts of potassium (K) and phosphate (P) but remains underutilized, leading to waste management and environmental concerns. This study investigates the potential of hydrothermal treatment (HT) to enhance the solubility of K and P for pressmud while assessing its influence on the energy characteristics of the resulting hydrochar. HT was conducted at 180^oC, 200^oC, and 220^oC under non-catalytic and zeolite-catalyzed conditions. The liquid fraction was analyzed for K and P concentrations using a photometer, while the hydrochar was evaluated for calorific value and proximate composition. The optimum treatment condition was achieved at 220^oC without zeolite, yielding the highest K and P solubilities of 1200 ppm and 1790 ppm, respectively. The presence of zeolite decreased solubility due to its ability to adsorb nutrients. Higher nutrient concentrations were positively correlated with increased calorific value and fixed carbon content, with a maximum value of 2047.56 cal/g. These findings demonstrate that hydrothermal treatment is an effective strategy for nutrient recovery and energy enhancement from pressmud waste, supporting its valorization toward renewable energy production and sustainable fertilizer development.</em></p> Asroful Abidin Wiyono Apri Fitriana Dina Rizkina Danang Kumara Hadi Copyright (c) 2025 Mechanical Science Reports 2025-10-07 2025-10-07 3 1 41 52 https://msr.bkstm.org/index.php/msr/article/view/18 <p><em>This experiment investigates the deformation behaviour of various string materials used in tensegrity structures, specifically in a tensegrity table, which is subjected to controlled loading conditions. Six types of strings with different diameters and material compositions were used in the experiment, including braided nylon (3, 4, and 5 mm), monofilament fishing string, braided fishing string, and fluorocarbon string. Measured under incremental loads of 5, 10, and 15 kg, the deformation of each string was observed to correlate with its mechanical characteristics, including stiffness, yield strength, and Young's modulus. The experiment shows that monofilament fishing string shows the least amount of deformation, making it the most structurally stable under various loading conditions, which is related to its material stiffness and minimal cross-sectional area. In contrast, braided nylon and fluorocarbon strings show higher deformation during testing, indicating that braided nylon and fluorocarbon is unsuitable for high-tension applications in tensegrity systems. This experiment offers insight into choosing the best string materials to improve the stability and load-bearing performance of tension structures, especially tensegrity tables.</em></p> Stivan Delon Sahertian Sean Michelino Lim Djati Wibowo Kushendarsyah Saptaji Copyright (c) 2025 Mechanical Science Reports 2025-10-07 2025-10-07 3 1 53 62