In this paper, we report the development and evaluation of an excretion detection device which is to be used with a cushion. Remarkably, the device does not require air suction and can be used during the daytime. The device can be placed on a chair or wheelchair and used whenever a cared person sits. Reflecting on the views of caregivers and the observations of the cared persons, the device was designed to be as thin and flexible as possible. In experiments to evaluate the response, it was confirmed to respond not only to simulated urine but also to actual excrement. From the results of the clinical experiments, the excretion detection model achieved an accuracy rate of 76%. Although this figure is close to the approximately 80% accuracy rate of an existing product H, it must be kept in mind that this accuracy rate is limited to urination owing to the limited training data in this study. These findings suggest that the device used with a cushion provides a valid means of excretion detection during daytime hours in a non-wearing and non-invasive manner, although its use is currently limited to urination.

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