Stem Antics on Instagram: "What you’re watching is a robotically controlled arm car performing high-precision material removal through wood. Behind this motion is a stack of engineering principles working together in real time: • Control systems engineering – Closed-loop feedback (often using PID controllers) continuously adjusts position, speed, and torque to maintain accuracy. • Kinematics & dynamics – Forward and inverse kinematics calculate joint angles and end-effector position in 3D space.