The advancement of CNC laser diode technology has transformed manufacturing by enabling high precision cutting and engraving of various materials, yet ensuring reliable operation requires accurate monitoring of electrical and mechanical parameters. This research focused on designing and implementing a real-time monitoring system that integrates the PZEM-004T sensor for electrical measurements and limit switches for safety boundaries in CNC laser diode machines. The system was developed using NodeMCU ESP8266 as the main controller, with results displayed on an LCD 16x2 and alarms generated through a buzzer and relay. Experimental evaluation demonstrated that the system effectively measured voltage, current, power, and energy, with the PZEM-004T showing an average error below 5% compared to reference instruments. The integration of limit switches functioned reliably, preventing mechanical failures and ensuring safe operation within defined limits. Monitoring data supported energy efficiency by identifying power usage patterns and reducing operational risks. Engraving tests confirmed stable performance, with improved detail observed during longer process durations. Overall, the implemented system provides a practical and reliable solution for operational monitoring and mechanical protection, making it particularly suitable for small-scale CNC laser diode applications in industrial, educational, and creative fields.

Socks are essential daily wear that require special care, including an effective drying process to prevent unpleasant odors and the growth of bacteria and fungi. Conventional drying methods often face challenges, especially in high-humidity environments or during unfavorable weather conditions. This study aims to design and develop a prototype sock dryer that is more efficient and hygienic. The prototype utilizes a combination of a heater, UV lamp, and humidity and temperature sensors to ensure optimal drying without damaging fabric fibers. A microcontroller-based control system using Arduino Uno is implemented to regulate device operation and monitor sock conditions during drying. Testing results indicate that the device effectively dries cotton socks in damp conditions faster than conventional methods. Additionally, the sterilization feature with a UV lamp helps reduce the risk of microbial growth. This innovation is expected to provide users with a practical, hygienic, and efficient way to dry socks without depending on weather conditions. Further development can be carried out to enhance drying capacity and energy efficiency.

The use of renewable energy has become an essential solution to reduce dependence on limited fossil energy sources. Solar panels are an environmentally friendly alternative for generating electrical energy. This study develops a solar panel system based on the Internet of Things (IoT) to provide energy for electric water heaters. The system allows for the monitoring and control of energy usage through an IoT-based application, such as Telegram. The solar panels are connected to an ESP32-based controller system, which monitors sunlight intensity and battery charging status. The test results indicate that this system can provide sufficient energy for electric water heaters with optimal efficiency and reduce dependence on conventional energy sources.