There, the sensor can measure atypical movement, like food slowdown potentially caused by gastrointestinal disorders. Or they could help doctors monitor food intake for patients treated for obesity. The team reported their research in the latest issue of the journal Nature Biomedical Engineering.

The sensors themselves are made from piezoelectric materials, which generate a current and voltage when they're bent out of shape. They also contain polymers that imitate the elasticity of human skin, so when the gastrointestinal walls they cling to flex and stretch, so do they. Plus, they're robust enough to survive up to two days during tests, when the researchers immersed the sensors in the stomachs of pigs.

In the future, the researchers hope to harness the sensor's piezoelectric potential -- i.e., generating energy whenever the device flexes to power other features. Such sensors of the future might not even need batteries and rely on the motion of the human body.