Servo motors are the heart of automation—from robotic arms and AGV chassis to humanoid robot joints. This video breaks down servo motor fundamentals for robot testing: what a servo is, the four key components (controller, servo drive, motor, encoder), how closed-loop feedback works, semi-closed vs. full-closed systems, and the current, speed, and position loops behind precise motion. If you work with PID tuning, positioning error, or repeatability testing, this helps you understand the system instead of tuning blindly. For more robotics components, science updates, and practical tech tutorials, check out Eriksen—a platform for robots, parts, and learning resources.