Jurnal Otomasi Kontrol dan Instrumentasi

Proportional-Controlled Microclimate Incubation System with IoT Monitoring for Dendrobium Seedling Acclimatization

2026-06-29T15:41:04+07:00

Dendrobium orchid seedlings transferred from in vitro culture require stable microclimate conditions during acclimatization, particularly temperature, humidity, and photoperiod regulation, to improve adaptation to non-aseptic environments. However, quantitative evaluations of laboratory-scale incubation systems under constrained actuation conditions remain limited. This study presents a compact microclimate incubation system implementing proportional-only temperature control using fan-based unidirectional cooling, scheduled irrigation and lighting, and real-time IoT monitoring through a Node-RED dashboard. The system was developed using an ESP32-S3 controller and DHT22 sensors in a semi-enclosed multi-tier rack with a capacity of 360 seedling pots. Sensor calibration showed strong agreement with a reference instrument, achieving R² > 0.99 for temperature and humidity measurements. Temperature regulation at a reference value of 29.3 °C achieved a steady-state mean absolute error of 0.1 °C within a deviation range of −0.5 to +0.1 °C during 572 minutes of continuous operation, while maintaining all measurements within ±2 °C of the thermal tolerance range for Dendrobium acclimatization. Increasing proportional gain from = 1000 to 2550 reduced the reference entry time from 362 s to 208 s. These findings demonstrate that proportional-only control with constrained cooling actuation can provide stable temperature regulation for compact indoor incubation systems.

Design and Development of a Low-Cost IoT-Based Portable Pulse Oximeter

2026-07-05T10:08:00+07:00

Real-time monitoring of heart rate and oxygen saturation is commonly performed using conventional medical devices that are impractical for daily use. This study aims to design a low-cost, Internet of Things (IoT)-based portable pulse oximeter prototype for real-time health monitoring. The system employs a MAX30100 sensor to measure BPM and SpO₂, an ESP32 microcontroller for data processing, and an OLED to display the results. The measured data are also transmitted to the Blynk application for remote smartphone monitoring. Performance was evaluated on 20 participants consisting of 10 men and 10 women, by comparing the measurement results with those of the commercial Serenity OX-48 pulse oximeter. System performance was assessed using accuracy, Mean Absolute Error (MAE), standard deviation, and Pearson correlation. The male group achieved an average accuracy of 98.71% for BPM (MAE = 1.09 BPM; r = 0.99) and 99.16% for SpO₂ (MAE = 0.80%; r = 0.92). Meanwhile, the female group achieved an average accuracy of 98.88% for BPM (MAE = 1.01 BPM; r = 0.99) and 99.17% for SpO₂ (MAE = 0.80%). These results indicate that the system delivers accurate, stable, and reliable measurements and is suitable for real-time IoT-based physiological monitoring.

Design and Development of a Low-Cost Automated Guided Vehicle (AGV) Prototype based on a Microcontroller for Internal Material Distribution in Industrial Small and Medium-Enterprises (SMEs)

2026-08-06T09:49:56+07:00

Small and medium-sized enterprises (SMEs) require internal material distribution systems that are efficient, safe, maintainable, and affordable. This study aims to design and test a low-cost microcontroller-based Automated Guided Vehicle (AGV) prototype for internal material distribution in SMEs. The system uses a differential drive configuration, BLDC motor driver, magnetic path navigation, Roboteq MGS1600 magnetic sensor, RPLIDAR C1, ESP32-C3, limit switches, emergency stop, modular battery, and STM32-based PCB control board. The research method includes requirement identification, design formulation, mechanical and electronic design, control software development, system integration, and functional testing. The results show that the magnetic sensor detected magnetic tape up to 3.0 cm. The obstacle detection system produced stopping-distance MAE values of 4.02 cm for human obstacles and 9.39 cm for object obstacles relative to the 30 cm setpoint. Motor-driver characterisation showed an effective PWM duty cycle range of 31-70%, with a saturation speed of about 283 RPM. The AGV prototype also towed approximately 403 kg on a flat track. These results indicate that the proposed AGV can serve as an economical initial alternative for material handling automation in SMEs.

Pressure Control System for the Production of Salted Duck Eggs Utilizing Constant and Pulsed Pressure Techniques

2026-07-05T09:30:27+07:00

Duck eggs (Anas javanica) are highly nutritious but prone to spoilage, making preservation methods such as salting necessary. However, traditional egg salting requires a relatively long processing time of approximately 10–14 days, making it less efficient for mass production. Consequently, a technology that can accelerate the salting process while maintaining an acceptable product quality is required. This study proposes an automatic egg salting system based on the principle of osmotic dehydration, employing two pressure modes: constant and pulsed. In the pulsed pressure mode, the salting process consisted of repeated cycles: a 7.5 min pressure phase, followed by a 15 min relaxation phase, whereas in the constant pressure mode, the pressure was maintained continuously throughout the salting process. The resulting products were evaluated for their salt content using the Mohr method, and sensory qualities were assessed through organoleptic tests. The results showed that in the constant-pressure mode, increasing the pressure from 1 to 2 bar over a 2-day processing period increased the salt content from 0.95% to 1.33%. Meanwhile, the pulsed pressure mode accelerated the salting process, achieving a salt content of 1.11% at 1 bar and 1.62% at 2 bars, approaching the results of traditional 10-day salting.

IoT Based Electrical Energy Consumption Monitoring System Design

2026-08-18T12:18:21+07:00

Conventional kWh meters have a functional limitation: they measure household electrical energy consumption without the ability to control electrical loads, which can lead to uncontrolled energy use and high electricity costs. This study aims to design and build an Internet of Things (IoT)-based energy monitoring system capable of tracking electrical parameters in real time while automatically and remotely controlling electrical loads. The novelty of this research lies in the variation of testing time, the type and capacity of loads used, and the evaluation of the system's energy-saving effectiveness under energy-limiting control. The system was evaluated using an error percentage calculation method, with a Taffware KWE-PM01 wattmeter as the comparison standard, the 5V Songle relay datasheet, and efficiency savings calculations. Results show that the PZEM-004T sensor's measurement error percentage remained below the ±5% tolerance limit, with a maximum error of 4.3%. Relay response time ranged from 0.2 to 1.3 seconds, and the system improved electrical energy efficiency by 31.01% for LED lamp loads and 30.83% for electric fan loads by setting a daily energy consumption limit for each load. Overall, the designed system proved reliable in terms of measurement accuracy, relay response time, and energy-saving efficiency.

Predictive Modeling Based on Aspen HYSYS for Rhodinol Content Estimation in Pilot-Scale Vacuum Fractional Distillation of Citronella Oil: Agreement Evaluation with Experimental Data

2026-09-14T09:34:47+07:00

Citronella oil is an essential oil widely used in the perfume, cosmetic, pharmaceutical, and natural-product industries owing to its high-value rhodinol content (citronellol and geraniol). This study aims to develop and evaluate a vacuum fractional distillation process model based on Aspen HYSYS software to predictive the relative rhodinol content of citronella oil and evaluate its agreement with the actual pilot-scale process. Feedstock characterization used GCMS and physicochemical testing. Modeling was performed by varying vacuum pressure, reboiler temperature, and reflux ratio to determine operating conditions tested on a pilot-scale vacuum fractional distillation unit through three experiments, comparing the relative rhodinol content from the model and experiments based on percentage error. Results show the third experiment produced the highest relative rhodinol content of 66.51% at 26 mbar, a reboiler temperature of 134°C, and a reflux ratio of 6:1, with prediction error ranging from 25.01% to 42.80% and the lowest error in the third experiment. These findings indicate the Aspen HYSYS model provides a predictive trend supporting the design of operating conditions but still shows deviation from actual pilot-scale conditions, indicating the need to refine model parameters, operating conditions, and process assumptions to improve model reliability for larger-scale process development.

Design and Development of an O-SEATER Simulation Platform for the BRIN Operational Area Using NVIDIA Isaac Sim

2026-09-10T10:35:02+07:00

Developing algorithms for mobile robot systems requires a simulation environment that models operational conditions. This research develops a simulation platform for the O-SEATER autonomous vehicle in the virtual environment of BRIN KST Samaun Samadikun using NVIDIA Isaac Sim. The virtual model was connected to the physical vehicle via a wireless network using the Robot Operating System 2 (ROS 2) for Hardware-in-the-Loop (HIL) and rosbag playback tests. The playback replicated the actual movements perfectly, with a Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) of 0.0000 and an ideal Real-Time Factor (RTF) of 1.0010. HIL simulation ran 1.81 times slower (RTF = 0.5518), with a memory spike of 27.1 GiB, 214.63 ms network latency, and 15% packet loss. To compensate for this temporal deviation, we applied Dynamic Time Warping (DTW), resulting in high-precision HIL tracking (Linear X MAE = 0.0299 m/s; Angular Z MAE = 0.0224 rad/s). The high communication latency is an architectural limitation. Nevertheless, we achieved interactive communication and generated virtual sensor data (RGB and IMU). This platform remains a sufficiently valid algorithm-testing medium and the basis of the O-SEATER Digital Twin system.