Self-Powered Wireless Urinary-Incontinence Sensor System Detecting Urine Amount and Diaper Change Timing in Under 10 Minutes

A self-powered wireless urinary-incontinence sensor system composed of a wireless sensor and a receiver has been developed that detects the amount of urine and the time for a diaper change. The wireless urinary-incontinence sensor, which consists of a urine-activated battery, an intermittent power-supply circuit with a storage capacitor, and a wireless transmitter, makes it possible to detect the number of urinations and the amount of urine from the spacing between the output signals. The urine-activated battery, which consists of two long flexible electrodes embedded in a diaper and placed under a piece of absorbent material with a trench structure, makes fast detection of less than 10 minutes possible. A prototype urinary-incontinence sensor system detected the amount of urine in a diaper from the spacing between the sensing signals with a resolution of 100 em3 and detected the time for a diaper change 7 minutes after urinations.