A paper published in Nature Scientific Reports describes researchers using a Dodotronic Ultramic384, an Oppo smartwatch, and a Xiaomi Mi A1 smartphone to record audio of the sound of a #1 hitting the water surface in a toilet bowl. The audio was analyzed using machine-learning regression algorithms to determined urine flow parameters such as voided volume and flow rate, and was compared with a commercial grade Minze uroflowmeter.
The tests involved peeing into a Minze uroflowmeter basin, and at the same time three different microphones recorded the sound. The Minze uroflowmeter was prefilled with 400 ml of water at the bottom of the container, to ensure that the sound generated by the twinkle was against the water, simulating the conditions of a real toilet bowl. All participants were given instructions asking them to aim at the toilet water.
The results showed there was very good correlation between using the smart devices and the ‘gold standard’ device.