OLED EMO Robot: A Low-Cost ESP32-Based Expressive Clock with Touch Interaction and a Planned Offline Voice Interface

This paper presents the design of the OLED EMO Robot, a compact interactive embedded device built around an ESP32 microcontroller. A DS3231 real-time clock (RTC) provides date and time, an OLED display presents the interface and animated facial expressions, and a TTP223 capacitive touch sensor lets the user trigger changes of expression or message. An INMP441 I2S digital microphone is proposed as a future voice-input module, starting with a small offline phrase set. The system is developed in the Arduino IDE and verified module by module. In the current prototype, I2C device detection, RTC time and date readout, and touch-state detection have been observed through the serial monitor, while OLED expression animation, voice input and battery monitoring are design targets. The paper describes the hardware architecture, software structure, test observations, limitations and a phased roadmap, and clearly separates tested features from planned ones.