Is it possible to give computers a sense of taste? This was the question that motivated researchers at IBM Research to develop HyperTaste, a tool for chemical taste sensing. It acts as an “electronic tongue”—a sensor that analyzes the chemical composition of liquids.

“HyperTaste was inspired by advances in AI and machine learning to mimic human senses like sight and hearing for recognizing images and interpreting speech,” says Patrick Ruch, a research staff member at IBM Research and coauthor of the paper on HyperTaste. “We wanted to present a new lens for chemical sensing.”

The idea was to apply a combinatorial approach using an array of sensors—much like the thousands of taste buds on our tongues—and then employ machine-learning algorithms to interpret the output of those sensors. The team used a printed circuit board with microcontroller-based hardware and an assembly of 16 conductive polymeric sensors that change their voltage when dipped in a solution. “It’s a bit similar to how a battery works, and it’s almost as if we’re using the liquid we want to test as an electrolyte,” Ruch says.

Dipping the array of sensors into a liquid generates a series of voltage signals unique to that liquid—its chemical fingerprint. These voltage signals are relayed to a mobile app, which transmits them to a cloud server, where a machine-learning model uses the data to train the algorithm and compare the fingerprint to a database of known liquids. The algorithm then reports the results—whether that’s identifying a liquid or just estimating its properties—back to the app within a minute or two.

“You don’t necessarily require a lab to do this, saving on both time and cost and accelerating the testing process,” says Ruch. “We wanted to use minimalistic, portable hardware and demonstrate that the intelligence of such a chemical sensing system could be pushed to the software side.”

Despite its operational simplicity, HyperTaste was not easy to develop. Bringing the various parts of the system together as well as merging an interdisciplinary team consisting of electrochemists and material scientists to determine HyperTaste’s sensing principle, electrical engineers to define and assemble the hardware, and software engineers for the data science and deployment side proved challenging.

“We had to integrate all these capabilities in the team and also find a common language to be able to understand the interfaces between these different components and the handoff points,” Ruch says. [READ MORE]