Robotic Chaotic Entropy Harvester

A double-jointed robot arm is a textbook chaotic system: the same Lagrangian equations that make a double pendulum unpredictable govern its elbow motion, and that unpredictability can be turned into a genuine source of cryptographic randomness. This simulator drives a 3D robot arm with a tunable mechanical noise torque, samples the low-order bits of its elbow angle at a configurable rate, and runs the raw stream through a real Von Neumann debiasing extractor before packing the output into a live hexadecimal key — with running readouts of raw Shannon entropy, output bit rate, and the extractor's discard rate so you can see exactly how much of the arm's physical unpredictability survives into usable key material.