Magnetorheological Damper: Field-Controlled Yield Stress

This simulator models a quarter-car magnetorheological (MR) damper: a piston moving through an iron-particle-loaded fluid inside an electromagnet coil. Raising the coil current polarises the suspended particles into field-aligned chains, giving the fluid a controllable Bingham-plastic yield stress on top of its ordinary viscosity. A mass-spring-damper system responds to a road profile — either a continuous sinusoidal excitation or a single triggered bump — and the damper force is computed each frame from the real relative piston velocity via the smoothed Bingham-plastic model, so the readouts and the visible chain alignment always match the physics driving the motion.