Bed Sensor System with Multiple Weight Sensor Units for Urine Accumulation Measurement in Bladder

Urinary incontinence is highly prevalent in elderly populations. Some elderly people with dementia cannot feel or express the desire to urinate, which makes continence care difficult in elderly people with dementia. Therefore, a system to estimate the proper timing for urination is needed. Because bladder volume is associated with the desire to void, it can be employed to estimate the proper timing. In this study, we developed a new bed sensor system that non-invasively and unconstrainedly measures urine accumulation in the bladder. To capture the slight weight change due to body alignment changes caused by body sinking in bed mattress, the system takes measurements in five body areas (head, torso, buttock, thigh, and lower limb) with five separate sensor units. We measured weight change during bladder voiding and urine accumulation in a human subject. Interestingly, the weight around head as well as buttock measured by the newly developed sensor system gradually increased when urine accumulated in the bladder, which suggested that the weight changes might reflect urine accumulation.