The official title of the study is:
A mountable toilet system for personalized health monitoring via the analysis of excreta
They use the Bristol stool scale and will also identify your analprint.
Upon completion of defecation or urination, the system uploads all of the user’s results to a protected cloud. Individual users are identified via a fingerprint scanner embedded in the flush lever as well as by “analprint” (yes, the researchers called it an analprint). A camera on the toilet module images the user’s anus, allowing an algorithm to link the anus image to a specific person on subsequent use.
Here is some of the content from the study:
Here, we describe easily deployable hardware and software for the long-term analysis of a user’s excreta through data collection and models of human health. The ‘smart’ toilet, which is self-contained and operates autonomously by leveraging pressure and motion sensors, analyses the user’s urine using a standard-of-care colorimetric assay that traces red–green–blue values from images of urinalysis strips, calculates the flow rate and volume of urine using computer vision as a uroflowmeter, and classifies stool according to the Bristol stool form scale using deep learning, with performance that is comparable to the performance of trained medical personnel.
Each user of the toilet is identified through their anal fingerprint and the distinctive features of their anoderm (ie: lining of the anal canal), and the data are securely stored and analysed in an encrypted cloud server. The toilet may find uses in the screening, diagnosis and longitudinal monitoring of specific patient populations.
We performed 410 fingerprinting [Ed note: butthole] trials from 10 participants … Among 11 participants, two video clips of the anus per participants were acquired from 7 participants, whereas one video clip of the anus per participant was acquired from 4 participants … As an input, individual frames of the anus from participant 1 were used for identification purposes.
And the general data collection method:
As a user sits on the toilet for a defecation event, the pressure sensor below the toilet seat initiates the defecation monitoring camera. The camera records the toilet bowl until the end of the defecation event. The collected images are then fed into deep CNN layers for stool classification.
Stanford University study published in Nature