CPR Chest Compression Biomechanics Simulator (2D)

This 2D cross-section companion to the 3D CPR simulator models the thorax as a rigid-body mass on a nonlinear spring-damper, driven by Newton's second law rather than a canned animation — identical physics to the 3D version, redrawn as a side-view diagram of ribs, sternum and heart. An adaptive force controller tunes each automatic push until the simulated depth converges on your target, or you can grab the chest directly and feel the spring-back recoil. Alongside the standard depth/rate/recoil readouts, this version adds a live estimate of coronary perfusion pressure — the pressure gradient that actually drives blood into the heart muscle during compressions — showing numerically why depth, rate and full recoil all have to line up together to give a real patient a chance at return of spontaneous circulation.