Haptic Needle Insertion Trainer

Physical medical simulators increasingly rely on force feedback rather than pure visuals: a trainee learns to recognize tissue planes by the resistance felt through the needle, not by seeing them. This simulator models that resistance curve directly — a cross-section of skin, fat and muscle sits over a hidden target vessel, and as the needle advances the live force meter changes with each layer, spiking briefly at every boundary crossing. Hand tremor is modeled as a small angular jitter at the entry point that grows into real lateral drift by the time the tip reaches depth, so unsteady hands miss more often even at the right insertion depth. Tune approach angle, insertion depth and tremor, then attempt a puncture to score accuracy against a freshly randomized patient.