This study aims to evaluate the diagnostic performance of a novel intelligent flexible penile monitoring system for erectile dysfunction (ED). The current gold standard, RigiScan Plus, often causes discomfort and disrupts sleep due to its mechanical rings, leading to potential "first-night effect" biases. This research utilizes a prospective crossover design to compare the accuracy of the new flexible system with RigiScan in measuring peak rigidity and tumescence. A total of 60 participants (30 ED patients and 30 healthy volunteers) will be enrolled. The study expects to confirm that the flexible system provides highly accurate diagnostic data while significantly improving patient comfort and maintaining natural sleep structures.