Design of an IoT-Based Electrical System for an Unmanned Solar-Powered Car Prototype

Abstract

The increasing development of renewable energy technologies has encouraged the integration of photovoltaic (PV) systems into small-scale electric vehicle platforms. This study aims to design and evaluate an Internet of Things (IoT)-based electrical system for an unmanned solar-powered car prototype using a 3 Wp monocrystalline solar panel. The electrical system consists of a solar panel, Schottky diode, PWM Solar Charge Controller (SCC), 18650 lithium-ion battery, ESP32 microcontroller, BTS7960 and L298N motor drivers, RS550 DC motor, and MG996R servo motor. The research employed a design and experimental method involving electrical system design, ESP32 programming using Arduino IDE, hardware assembly, and experimental testing. Voltage, current, ambient temperature, power consumption, battery charging time, and system operating time were evaluated. Experimental results showed that the solar panel produced voltages of 6.8–8.9 V and currents of 0.30–0.37 A during testing from 10:00 to 16:00 WIB. The average voltage and current were 7.60 V and 0.34 A, respectively, corresponding to an average power output of 2.58 W and estimated daily energy production of 20.64 Wh. Battery charging efficiency was approximately 85%, with an equivalent charging duration of approximately 14.8 h at the measured average PV power. The total electrical load was 78.8 W, resulting in an estimated operating time of approximately 25 min when the battery was fully charged. The ESP32-based Bluetooth control system successfully controlled the DC motor and steering servo with stable response. The prototype is primarily intended as an educational and experimental platform for studying the integration of photovoltaic energy, battery storage, and IoT-based control, rather than as a fully self-sustained solar-powered vehicle.