Arduino-Controlled Namaste Greeting Robot

The Arduino-Controlled Namaste Greeting Robot operates by combining sensing, processing, and physical actuation to welcome visitors automatically. At the heart of the system is an Arduino Uno board, which coordinates all inputs and outputs. The HC-SR04 ultrasonic transceiver module acts as the robot's eyes by continuously emitting high-frequency sound waves and measuring how long they take to bounce back off nearby objects. When a person steps within the detection range, the HC-SR04 sends this distance data back to the Arduino Uno. Once the Arduino detects a visitor within the threshold distance, it triggers two primary responses. First, it sends control signals to a series of servo motors (labeled M1 through M5) responsible for moving the robot's elbows, shoulders, and head. Using the built-in Servo.h library, the Arduino generates precise pulse-width modulation (PWM) signals that command these motors to coordinate a traditional 'namaste' bowing posture. Simultaneously, the Arduino interacts with the APR9301 voice recording and playback IC (IC1). This integrated circuit stores a pre-recorded audio greeting, which is triggered alongside the physical movement to emit a welcoming voice message through a connected speaker setup. Power is supplied to the entire circuit via a dedicated power supply that ensures the Arduino and all five servo motors receive adequate voltage and current to operate smoothly without dropping voltage levels during heavy mechanical movement.